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/archiveUtils.hpp" 27 #include "cds/cdsConfig.hpp" 28 #include "cds/cdsEnumKlass.hpp" 29 #include "cds/classListWriter.hpp" 30 #include "cds/heapShared.hpp" 31 #include "cds/metaspaceShared.hpp" 32 #include "classfile/classFileParser.hpp" 33 #include "classfile/classFileStream.hpp" 34 #include "classfile/classLoader.hpp" 35 #include "classfile/classLoaderData.inline.hpp" 36 #include "classfile/javaClasses.hpp" 37 #include "classfile/moduleEntry.hpp" 38 #include "classfile/systemDictionary.hpp" 39 #include "classfile/systemDictionaryShared.hpp" 40 #include "classfile/verifier.hpp" 41 #include "classfile/vmClasses.hpp" 42 #include "classfile/vmSymbols.hpp" 43 #include "code/codeCache.hpp" 44 #include "code/dependencyContext.hpp" 45 #include "compiler/compilationPolicy.hpp" 46 #include "compiler/compileBroker.hpp" 47 #include "gc/shared/collectedHeap.inline.hpp" 48 #include "interpreter/bytecodeStream.hpp" 49 #include "interpreter/oopMapCache.hpp" 50 #include "interpreter/rewriter.hpp" 51 #include "jvm.h" 52 #include "jvmtifiles/jvmti.h" 53 #include "logging/log.hpp" 54 #include "klass.inline.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/fieldStreams.inline.hpp" 65 #include "oops/constantPool.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/deoptimization.hpp" 82 #include "runtime/atomic.hpp" 83 #include "runtime/fieldDescriptor.inline.hpp" 84 #include "runtime/handles.inline.hpp" 85 #include "runtime/javaCalls.hpp" 86 #include "runtime/javaThread.inline.hpp" 87 #include "runtime/mutexLocker.hpp" 88 #include "runtime/orderAccess.hpp" 89 #include "runtime/os.inline.hpp" 90 #include "runtime/reflection.hpp" 91 #include "runtime/synchronizer.hpp" 92 #include "runtime/threads.hpp" 93 #include "services/classLoadingService.hpp" 94 #include "services/finalizerService.hpp" 95 #include "services/threadService.hpp" 96 #include "utilities/dtrace.hpp" 97 #include "utilities/events.hpp" 98 #include "utilities/macros.hpp" 99 #include "utilities/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_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 void* InstanceKlass::operator new(size_t size, ClassLoaderData* loader_data, size_t word_size, 459 bool use_class_space, TRAPS) throw() { 460 return Metaspace::allocate(loader_data, word_size, ClassType, use_class_space, THREAD); 461 } 462 463 InstanceKlass* InstanceKlass::allocate_instance_klass(const ClassFileParser& parser, TRAPS) { 464 const int size = InstanceKlass::size(parser.vtable_size(), 465 parser.itable_size(), 466 nonstatic_oop_map_size(parser.total_oop_map_count()), 467 parser.is_interface()); 468 469 const Symbol* const class_name = parser.class_name(); 470 assert(class_name != nullptr, "invariant"); 471 ClassLoaderData* loader_data = parser.loader_data(); 472 assert(loader_data != nullptr, "invariant"); 473 474 InstanceKlass* ik; 475 const bool use_class_space = parser.klass_needs_narrow_id(); 476 477 // Allocation 478 if (parser.is_instance_ref_klass()) { 479 // java.lang.ref.Reference 480 ik = new (loader_data, size, use_class_space, THREAD) InstanceRefKlass(parser); 481 } else if (class_name == vmSymbols::java_lang_Class()) { 482 // mirror - java.lang.Class 483 ik = new (loader_data, size, use_class_space, THREAD) InstanceMirrorKlass(parser); 484 } else if (is_stack_chunk_class(class_name, loader_data)) { 485 // stack chunk 486 ik = new (loader_data, size, use_class_space, THREAD) InstanceStackChunkKlass(parser); 487 } else if (is_class_loader(class_name, parser)) { 488 // class loader - java.lang.ClassLoader 489 ik = new (loader_data, size, use_class_space, THREAD) InstanceClassLoaderKlass(parser); 490 } else { 491 // normal 492 ik = new (loader_data, size, use_class_space, THREAD) InstanceKlass(parser); 493 } 494 495 if (ik != nullptr && UseCompressedClassPointers && use_class_space) { 496 assert(CompressedKlassPointers::is_encodable(ik), 497 "Klass " PTR_FORMAT "needs a narrow Klass ID, but is not encodable", p2i(ik)); 498 } 499 500 // Check for pending exception before adding to the loader data and incrementing 501 // class count. Can get OOM here. 502 if (HAS_PENDING_EXCEPTION) { 503 return nullptr; 504 } 505 506 return ik; 507 } 508 509 510 // copy method ordering from resource area to Metaspace 511 void InstanceKlass::copy_method_ordering(const intArray* m, TRAPS) { 512 if (m != nullptr) { 513 // allocate a new array and copy contents (memcpy?) 514 _method_ordering = MetadataFactory::new_array<int>(class_loader_data(), m->length(), CHECK); 515 for (int i = 0; i < m->length(); i++) { 516 _method_ordering->at_put(i, m->at(i)); 517 } 518 } else { 519 _method_ordering = Universe::the_empty_int_array(); 520 } 521 } 522 523 // create a new array of vtable_indices for default methods 524 Array<int>* InstanceKlass::create_new_default_vtable_indices(int len, TRAPS) { 525 Array<int>* vtable_indices = MetadataFactory::new_array<int>(class_loader_data(), len, CHECK_NULL); 526 assert(default_vtable_indices() == nullptr, "only create once"); 527 set_default_vtable_indices(vtable_indices); 528 return vtable_indices; 529 } 530 531 532 InstanceKlass::InstanceKlass() { 533 assert(CDSConfig::is_dumping_static_archive() || CDSConfig::is_using_archive(), "only for CDS"); 534 } 535 536 InstanceKlass::InstanceKlass(const ClassFileParser& parser, KlassKind kind, ReferenceType reference_type) : 537 Klass(kind), 538 _nest_members(nullptr), 539 _nest_host(nullptr), 540 _permitted_subclasses(nullptr), 541 _record_components(nullptr), 542 _static_field_size(parser.static_field_size()), 543 _nonstatic_oop_map_size(nonstatic_oop_map_size(parser.total_oop_map_count())), 544 _itable_len(parser.itable_size()), 545 _nest_host_index(0), 546 _init_state(allocated), 547 _reference_type(reference_type), 548 _init_thread(nullptr) 549 { 550 set_vtable_length(parser.vtable_size()); 551 set_access_flags(parser.access_flags()); 552 if (parser.is_hidden()) set_is_hidden(); 553 set_layout_helper(Klass::instance_layout_helper(parser.layout_size(), 554 false)); 555 556 assert(nullptr == _methods, "underlying memory not zeroed?"); 557 assert(is_instance_klass(), "is layout incorrect?"); 558 assert(size_helper() == parser.layout_size(), "incorrect size_helper?"); 559 } 560 561 void InstanceKlass::deallocate_methods(ClassLoaderData* loader_data, 562 Array<Method*>* methods) { 563 if (methods != nullptr && methods != Universe::the_empty_method_array() && 564 !methods->is_shared()) { 565 for (int i = 0; i < methods->length(); i++) { 566 Method* method = methods->at(i); 567 if (method == nullptr) continue; // maybe null if error processing 568 // Only want to delete methods that are not executing for RedefineClasses. 569 // The previous version will point to them so they're not totally dangling 570 assert (!method->on_stack(), "shouldn't be called with methods on stack"); 571 MetadataFactory::free_metadata(loader_data, method); 572 } 573 MetadataFactory::free_array<Method*>(loader_data, methods); 574 } 575 } 576 577 void InstanceKlass::deallocate_interfaces(ClassLoaderData* loader_data, 578 const Klass* super_klass, 579 Array<InstanceKlass*>* local_interfaces, 580 Array<InstanceKlass*>* transitive_interfaces) { 581 // Only deallocate transitive interfaces if not empty, same as super class 582 // or same as local interfaces. See code in parseClassFile. 583 Array<InstanceKlass*>* ti = transitive_interfaces; 584 if (ti != Universe::the_empty_instance_klass_array() && ti != local_interfaces) { 585 // check that the interfaces don't come from super class 586 Array<InstanceKlass*>* sti = (super_klass == nullptr) ? nullptr : 587 InstanceKlass::cast(super_klass)->transitive_interfaces(); 588 if (ti != sti && ti != nullptr && !ti->is_shared()) { 589 MetadataFactory::free_array<InstanceKlass*>(loader_data, ti); 590 } 591 } 592 593 // local interfaces can be empty 594 if (local_interfaces != Universe::the_empty_instance_klass_array() && 595 local_interfaces != nullptr && !local_interfaces->is_shared()) { 596 MetadataFactory::free_array<InstanceKlass*>(loader_data, local_interfaces); 597 } 598 } 599 600 void InstanceKlass::deallocate_record_components(ClassLoaderData* loader_data, 601 Array<RecordComponent*>* record_components) { 602 if (record_components != nullptr && !record_components->is_shared()) { 603 for (int i = 0; i < record_components->length(); i++) { 604 RecordComponent* record_component = record_components->at(i); 605 MetadataFactory::free_metadata(loader_data, record_component); 606 } 607 MetadataFactory::free_array<RecordComponent*>(loader_data, record_components); 608 } 609 } 610 611 // This function deallocates the metadata and C heap pointers that the 612 // InstanceKlass points to. 613 void InstanceKlass::deallocate_contents(ClassLoaderData* loader_data) { 614 // Orphan the mirror first, CMS thinks it's still live. 615 if (java_mirror() != nullptr) { 616 java_lang_Class::set_klass(java_mirror(), nullptr); 617 } 618 619 // Also remove mirror from handles 620 loader_data->remove_handle(_java_mirror); 621 622 // Need to take this class off the class loader data list. 623 loader_data->remove_class(this); 624 625 // The array_klass for this class is created later, after error handling. 626 // For class redefinition, we keep the original class so this scratch class 627 // doesn't have an array class. Either way, assert that there is nothing 628 // to deallocate. 629 assert(array_klasses() == nullptr, "array classes shouldn't be created for this class yet"); 630 631 // Release C heap allocated data that this points to, which includes 632 // reference counting symbol names. 633 // Can't release the constant pool or MethodData C heap data here because the constant 634 // pool can be deallocated separately from the InstanceKlass for default methods and 635 // redefine classes. MethodData can also be released separately. 636 release_C_heap_structures(/* release_sub_metadata */ false); 637 638 deallocate_methods(loader_data, methods()); 639 set_methods(nullptr); 640 641 deallocate_record_components(loader_data, record_components()); 642 set_record_components(nullptr); 643 644 if (method_ordering() != nullptr && 645 method_ordering() != Universe::the_empty_int_array() && 646 !method_ordering()->is_shared()) { 647 MetadataFactory::free_array<int>(loader_data, method_ordering()); 648 } 649 set_method_ordering(nullptr); 650 651 // default methods can be empty 652 if (default_methods() != nullptr && 653 default_methods() != Universe::the_empty_method_array() && 654 !default_methods()->is_shared()) { 655 MetadataFactory::free_array<Method*>(loader_data, default_methods()); 656 } 657 // Do NOT deallocate the default methods, they are owned by superinterfaces. 658 set_default_methods(nullptr); 659 660 // default methods vtable indices can be empty 661 if (default_vtable_indices() != nullptr && 662 !default_vtable_indices()->is_shared()) { 663 MetadataFactory::free_array<int>(loader_data, default_vtable_indices()); 664 } 665 set_default_vtable_indices(nullptr); 666 667 668 // This array is in Klass, but remove it with the InstanceKlass since 669 // this place would be the only caller and it can share memory with transitive 670 // interfaces. 671 if (secondary_supers() != nullptr && 672 secondary_supers() != Universe::the_empty_klass_array() && 673 // see comments in compute_secondary_supers about the following cast 674 (address)(secondary_supers()) != (address)(transitive_interfaces()) && 675 !secondary_supers()->is_shared()) { 676 MetadataFactory::free_array<Klass*>(loader_data, secondary_supers()); 677 } 678 set_secondary_supers(nullptr, SECONDARY_SUPERS_BITMAP_EMPTY); 679 680 deallocate_interfaces(loader_data, super(), local_interfaces(), transitive_interfaces()); 681 set_transitive_interfaces(nullptr); 682 set_local_interfaces(nullptr); 683 684 if (fieldinfo_stream() != nullptr && !fieldinfo_stream()->is_shared()) { 685 MetadataFactory::free_array<u1>(loader_data, fieldinfo_stream()); 686 } 687 set_fieldinfo_stream(nullptr); 688 689 if (fieldinfo_search_table() != nullptr && !fieldinfo_search_table()->is_shared()) { 690 MetadataFactory::free_array<u1>(loader_data, fieldinfo_search_table()); 691 } 692 set_fieldinfo_search_table(nullptr); 693 694 if (fields_status() != nullptr && !fields_status()->is_shared()) { 695 MetadataFactory::free_array<FieldStatus>(loader_data, fields_status()); 696 } 697 set_fields_status(nullptr); 698 699 // If a method from a redefined class is using this constant pool, don't 700 // delete it, yet. The new class's previous version will point to this. 701 if (constants() != nullptr) { 702 assert (!constants()->on_stack(), "shouldn't be called if anything is onstack"); 703 if (!constants()->is_shared()) { 704 MetadataFactory::free_metadata(loader_data, constants()); 705 } 706 // Delete any cached resolution errors for the constant pool 707 SystemDictionary::delete_resolution_error(constants()); 708 709 set_constants(nullptr); 710 } 711 712 if (inner_classes() != nullptr && 713 inner_classes() != Universe::the_empty_short_array() && 714 !inner_classes()->is_shared()) { 715 MetadataFactory::free_array<jushort>(loader_data, inner_classes()); 716 } 717 set_inner_classes(nullptr); 718 719 if (nest_members() != nullptr && 720 nest_members() != Universe::the_empty_short_array() && 721 !nest_members()->is_shared()) { 722 MetadataFactory::free_array<jushort>(loader_data, nest_members()); 723 } 724 set_nest_members(nullptr); 725 726 if (permitted_subclasses() != nullptr && 727 permitted_subclasses() != Universe::the_empty_short_array() && 728 !permitted_subclasses()->is_shared()) { 729 MetadataFactory::free_array<jushort>(loader_data, permitted_subclasses()); 730 } 731 set_permitted_subclasses(nullptr); 732 733 // We should deallocate the Annotations instance if it's not in shared spaces. 734 if (annotations() != nullptr && !annotations()->is_shared()) { 735 MetadataFactory::free_metadata(loader_data, annotations()); 736 } 737 set_annotations(nullptr); 738 739 SystemDictionaryShared::handle_class_unloading(this); 740 741 #if INCLUDE_CDS_JAVA_HEAP 742 if (CDSConfig::is_dumping_heap()) { 743 HeapShared::remove_scratch_objects(this); 744 } 745 #endif 746 } 747 748 bool InstanceKlass::is_record() const { 749 return _record_components != nullptr && 750 is_final() && 751 java_super() == vmClasses::Record_klass(); 752 } 753 754 bool InstanceKlass::is_sealed() const { 755 return _permitted_subclasses != nullptr && 756 _permitted_subclasses != Universe::the_empty_short_array(); 757 } 758 759 // JLS 8.9: An enum class is either implicitly final and derives 760 // from java.lang.Enum, or else is implicitly sealed to its 761 // anonymous subclasses. This query detects both kinds. 762 // It does not validate the finality or 763 // sealing conditions: it merely checks for a super of Enum. 764 // This is sufficient for recognizing well-formed enums. 765 bool InstanceKlass::is_enum_subclass() const { 766 InstanceKlass* s = java_super(); 767 return (s == vmClasses::Enum_klass() || 768 (s != nullptr && s->java_super() == vmClasses::Enum_klass())); 769 } 770 771 bool InstanceKlass::should_be_initialized() const { 772 return !is_initialized(); 773 } 774 775 klassItable InstanceKlass::itable() const { 776 return klassItable(const_cast<InstanceKlass*>(this)); 777 } 778 779 // JVMTI spec thinks there are signers and protection domain in the 780 // instanceKlass. These accessors pretend these fields are there. 781 // The hprof specification also thinks these fields are in InstanceKlass. 782 oop InstanceKlass::protection_domain() const { 783 // return the protection_domain from the mirror 784 return java_lang_Class::protection_domain(java_mirror()); 785 } 786 787 objArrayOop InstanceKlass::signers() const { 788 // return the signers from the mirror 789 return java_lang_Class::signers(java_mirror()); 790 } 791 792 oop InstanceKlass::init_lock() const { 793 // return the init lock from the mirror 794 oop lock = java_lang_Class::init_lock(java_mirror()); 795 // Prevent reordering with any access of initialization state 796 OrderAccess::loadload(); 797 assert(lock != nullptr || !is_not_initialized(), // initialized or in_error state 798 "only fully initialized state can have a null lock"); 799 return lock; 800 } 801 802 void InstanceKlass::initialize_preemptable(TRAPS) { 803 if (this->should_be_initialized()) { 804 PREEMPT_ON_INIT_SUPPORTED_ONLY(PreemptableInitCall pic(THREAD, this);) 805 initialize_impl(THREAD); 806 } else { 807 assert(is_initialized(), "sanity check"); 808 } 809 } 810 811 // See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization 812 // process. The step comments refers to the procedure described in that section. 813 // Note: implementation moved to static method to expose the this pointer. 814 void InstanceKlass::initialize(TRAPS) { 815 if (this->should_be_initialized()) { 816 initialize_impl(CHECK); 817 // Note: at this point the class may be initialized 818 // OR it may be in the state of being initialized 819 // in case of recursive initialization! 820 } else { 821 assert(is_initialized(), "sanity check"); 822 } 823 } 824 825 #ifdef ASSERT 826 void InstanceKlass::assert_no_clinit_will_run_for_aot_initialized_class() const { 827 assert(has_aot_initialized_mirror(), "must be"); 828 829 InstanceKlass* s = java_super(); 830 if (s != nullptr) { 831 DEBUG_ONLY(ResourceMark rm); 832 assert(s->is_initialized(), "super class %s of aot-inited class %s must have been initialized", 833 s->external_name(), external_name()); 834 s->assert_no_clinit_will_run_for_aot_initialized_class(); 835 } 836 837 Array<InstanceKlass*>* interfaces = local_interfaces(); 838 int len = interfaces->length(); 839 for (int i = 0; i < len; i++) { 840 InstanceKlass* intf = interfaces->at(i); 841 if (!intf->is_initialized()) { 842 ResourceMark rm; 843 // Note: an interface needs to be marked as is_initialized() only if 844 // - it has a <clinit> 845 // - it has declared a default method. 846 assert(!intf->interface_needs_clinit_execution_as_super(/*also_check_supers*/false), 847 "uninitialized super interface %s of aot-inited class %s must not have <clinit>", 848 intf->external_name(), external_name()); 849 } 850 } 851 } 852 #endif 853 854 #if INCLUDE_CDS 855 void InstanceKlass::initialize_with_aot_initialized_mirror(TRAPS) { 856 assert(has_aot_initialized_mirror(), "must be"); 857 assert(CDSConfig::is_loading_heap(), "must be"); 858 assert(CDSConfig::is_using_aot_linked_classes(), "must be"); 859 assert_no_clinit_will_run_for_aot_initialized_class(); 860 861 if (is_initialized()) { 862 return; 863 } 864 865 if (is_runtime_setup_required()) { 866 // Need to take the slow path, which will call the runtimeSetup() function instead 867 // of <clinit> 868 initialize(CHECK); 869 return; 870 } 871 if (log_is_enabled(Info, aot, init)) { 872 ResourceMark rm; 873 log_info(aot, init)("%s (aot-inited)", external_name()); 874 } 875 876 link_class(CHECK); 877 878 #ifdef ASSERT 879 { 880 Handle h_init_lock(THREAD, init_lock()); 881 ObjectLocker ol(h_init_lock, THREAD); 882 assert(!is_initialized(), "sanity"); 883 assert(!is_being_initialized(), "sanity"); 884 assert(!is_in_error_state(), "sanity"); 885 } 886 #endif 887 888 set_init_thread(THREAD); 889 set_initialization_state_and_notify(fully_initialized, CHECK); 890 } 891 #endif 892 893 bool InstanceKlass::verify_code(TRAPS) { 894 // 1) Verify the bytecodes 895 return Verifier::verify(this, should_verify_class(), THREAD); 896 } 897 898 void InstanceKlass::link_class(TRAPS) { 899 assert(is_loaded(), "must be loaded"); 900 if (!is_linked()) { 901 link_class_impl(CHECK); 902 } 903 } 904 905 // Called to verify that a class can link during initialization, without 906 // throwing a VerifyError. 907 bool InstanceKlass::link_class_or_fail(TRAPS) { 908 assert(is_loaded(), "must be loaded"); 909 if (!is_linked()) { 910 link_class_impl(CHECK_false); 911 } 912 return is_linked(); 913 } 914 915 bool InstanceKlass::link_class_impl(TRAPS) { 916 if (CDSConfig::is_dumping_static_archive() && SystemDictionaryShared::has_class_failed_verification(this)) { 917 // This is for CDS static dump only -- we use the in_error_state to indicate that 918 // the class has failed verification. Throwing the NoClassDefFoundError here is just 919 // a convenient way to stop repeat attempts to verify the same (bad) class. 920 // 921 // Note that the NoClassDefFoundError is not part of the JLS, and should not be thrown 922 // if we are executing Java code. This is not a problem for CDS dumping phase since 923 // it doesn't execute any Java code. 924 ResourceMark rm(THREAD); 925 // Names are all known to be < 64k so we know this formatted message is not excessively large. 926 Exceptions::fthrow(THREAD_AND_LOCATION, 927 vmSymbols::java_lang_NoClassDefFoundError(), 928 "Class %s, or one of its supertypes, failed class initialization", 929 external_name()); 930 return false; 931 } 932 // return if already verified 933 if (is_linked()) { 934 return true; 935 } 936 937 // Timing 938 // timer handles recursion 939 JavaThread* jt = THREAD; 940 941 // link super class before linking this class 942 Klass* super_klass = super(); 943 if (super_klass != nullptr) { 944 if (super_klass->is_interface()) { // check if super class is an interface 945 ResourceMark rm(THREAD); 946 // Names are all known to be < 64k so we know this formatted message is not excessively large. 947 Exceptions::fthrow( 948 THREAD_AND_LOCATION, 949 vmSymbols::java_lang_IncompatibleClassChangeError(), 950 "class %s has interface %s as super class", 951 external_name(), 952 super_klass->external_name() 953 ); 954 return false; 955 } 956 957 InstanceKlass* ik_super = InstanceKlass::cast(super_klass); 958 ik_super->link_class_impl(CHECK_false); 959 } 960 961 // link all interfaces implemented by this class before linking this class 962 Array<InstanceKlass*>* interfaces = local_interfaces(); 963 int num_interfaces = interfaces->length(); 964 for (int index = 0; index < num_interfaces; index++) { 965 InstanceKlass* interk = interfaces->at(index); 966 interk->link_class_impl(CHECK_false); 967 } 968 969 // in case the class is linked in the process of linking its superclasses 970 if (is_linked()) { 971 return true; 972 } 973 974 // trace only the link time for this klass that includes 975 // the verification time 976 PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(), 977 ClassLoader::perf_class_link_selftime(), 978 ClassLoader::perf_classes_linked(), 979 jt->get_thread_stat()->perf_recursion_counts_addr(), 980 jt->get_thread_stat()->perf_timers_addr(), 981 PerfClassTraceTime::CLASS_LINK); 982 983 // verification & rewriting 984 { 985 HandleMark hm(THREAD); 986 Handle h_init_lock(THREAD, init_lock()); 987 ObjectLocker ol(h_init_lock, CHECK_PREEMPTABLE_false); 988 // Don't preempt once we own the monitor as that would complicate 989 // redoing the VM call (we don't expect to own this monitor). 990 NoPreemptMark npm(THREAD); 991 992 // rewritten will have been set if loader constraint error found 993 // on an earlier link attempt 994 // don't verify or rewrite if already rewritten 995 // 996 997 if (!is_linked()) { 998 if (!is_rewritten()) { 999 if (is_shared()) { 1000 assert(!verified_at_dump_time(), "must be"); 1001 } 1002 { 1003 bool verify_ok = verify_code(THREAD); 1004 if (!verify_ok) { 1005 return false; 1006 } 1007 } 1008 1009 // Just in case a side-effect of verify linked this class already 1010 // (which can sometimes happen since the verifier loads classes 1011 // using custom class loaders, which are free to initialize things) 1012 if (is_linked()) { 1013 return true; 1014 } 1015 1016 // also sets rewritten 1017 rewrite_class(CHECK_false); 1018 } else if (is_shared()) { 1019 SystemDictionaryShared::check_verification_constraints(this, CHECK_false); 1020 } 1021 1022 // relocate jsrs and link methods after they are all rewritten 1023 link_methods(CHECK_false); 1024 1025 // Initialize the vtable and interface table after 1026 // methods have been rewritten since rewrite may 1027 // fabricate new Method*s. 1028 // also does loader constraint checking 1029 // 1030 // initialize_vtable and initialize_itable need to be rerun 1031 // for a shared class if 1032 // 1) the class is loaded by custom class loader or 1033 // 2) the class is loaded by built-in class loader but failed to add archived loader constraints or 1034 // 3) the class was not verified during dump time 1035 bool need_init_table = true; 1036 if (is_shared() && verified_at_dump_time() && 1037 SystemDictionaryShared::check_linking_constraints(THREAD, this)) { 1038 need_init_table = false; 1039 } 1040 if (need_init_table) { 1041 vtable().initialize_vtable_and_check_constraints(CHECK_false); 1042 itable().initialize_itable_and_check_constraints(CHECK_false); 1043 } 1044 #ifdef ASSERT 1045 vtable().verify(tty, true); 1046 // In case itable verification is ever added. 1047 // itable().verify(tty, true); 1048 #endif 1049 if (Universe::is_fully_initialized()) { 1050 DeoptimizationScope deopt_scope; 1051 { 1052 // Now mark all code that assumes the class is not linked. 1053 // Set state under the Compile_lock also. 1054 MutexLocker ml(THREAD, Compile_lock); 1055 1056 set_init_state(linked); 1057 CodeCache::mark_dependents_on(&deopt_scope, this); 1058 } 1059 // Perform the deopt handshake outside Compile_lock. 1060 deopt_scope.deoptimize_marked(); 1061 } else { 1062 set_init_state(linked); 1063 } 1064 if (JvmtiExport::should_post_class_prepare()) { 1065 JvmtiExport::post_class_prepare(THREAD, this); 1066 } 1067 } 1068 } 1069 return true; 1070 } 1071 1072 // Rewrite the byte codes of all of the methods of a class. 1073 // The rewriter must be called exactly once. Rewriting must happen after 1074 // verification but before the first method of the class is executed. 1075 void InstanceKlass::rewrite_class(TRAPS) { 1076 assert(is_loaded(), "must be loaded"); 1077 if (is_rewritten()) { 1078 assert(is_shared(), "rewriting an unshared class?"); 1079 return; 1080 } 1081 Rewriter::rewrite(this, CHECK); 1082 set_rewritten(); 1083 } 1084 1085 // Now relocate and link method entry points after class is rewritten. 1086 // This is outside is_rewritten flag. In case of an exception, it can be 1087 // executed more than once. 1088 void InstanceKlass::link_methods(TRAPS) { 1089 PerfTraceTime timer(ClassLoader::perf_ik_link_methods_time()); 1090 1091 int len = methods()->length(); 1092 for (int i = len-1; i >= 0; i--) { 1093 methodHandle m(THREAD, methods()->at(i)); 1094 1095 // Set up method entry points for compiler and interpreter . 1096 m->link_method(m, CHECK); 1097 } 1098 } 1099 1100 // Eagerly initialize superinterfaces that declare default methods (concrete instance: any access) 1101 void InstanceKlass::initialize_super_interfaces(TRAPS) { 1102 assert (has_nonstatic_concrete_methods(), "caller should have checked this"); 1103 for (int i = 0; i < local_interfaces()->length(); ++i) { 1104 InstanceKlass* ik = local_interfaces()->at(i); 1105 1106 // Initialization is depth first search ie. we start with top of the inheritance tree 1107 // has_nonstatic_concrete_methods drives searching superinterfaces since it 1108 // means has_nonstatic_concrete_methods in its superinterface hierarchy 1109 if (ik->has_nonstatic_concrete_methods()) { 1110 ik->initialize_super_interfaces(CHECK); 1111 } 1112 1113 // Only initialize() interfaces that "declare" concrete methods. 1114 if (ik->should_be_initialized() && ik->declares_nonstatic_concrete_methods()) { 1115 ik->initialize(CHECK); 1116 } 1117 } 1118 } 1119 1120 using InitializationErrorTable = ResourceHashtable<const InstanceKlass*, OopHandle, 107, AnyObj::C_HEAP, mtClass>; 1121 static InitializationErrorTable* _initialization_error_table; 1122 1123 void InstanceKlass::add_initialization_error(JavaThread* current, Handle exception) { 1124 // Create the same exception with a message indicating the thread name, 1125 // and the StackTraceElements. 1126 Handle init_error = java_lang_Throwable::create_initialization_error(current, exception); 1127 ResourceMark rm(current); 1128 if (init_error.is_null()) { 1129 log_trace(class, init)("Unable to create the desired initialization error for class %s", external_name()); 1130 1131 // We failed to create the new exception, most likely due to either out-of-memory or 1132 // a stackoverflow error. If the original exception was either of those then we save 1133 // the shared, pre-allocated, stackless, instance of that exception. 1134 if (exception->klass() == vmClasses::StackOverflowError_klass()) { 1135 log_debug(class, init)("Using shared StackOverflowError as initialization error for class %s", external_name()); 1136 init_error = Handle(current, Universe::class_init_stack_overflow_error()); 1137 } else if (exception->klass() == vmClasses::OutOfMemoryError_klass()) { 1138 log_debug(class, init)("Using shared OutOfMemoryError as initialization error for class %s", external_name()); 1139 init_error = Handle(current, Universe::class_init_out_of_memory_error()); 1140 } else { 1141 return; 1142 } 1143 } 1144 1145 MutexLocker ml(current, ClassInitError_lock); 1146 OopHandle elem = OopHandle(Universe::vm_global(), init_error()); 1147 bool created; 1148 if (_initialization_error_table == nullptr) { 1149 _initialization_error_table = new (mtClass) InitializationErrorTable(); 1150 } 1151 _initialization_error_table->put_if_absent(this, elem, &created); 1152 assert(created, "Initialization is single threaded"); 1153 log_trace(class, init)("Initialization error added for class %s", external_name()); 1154 } 1155 1156 oop InstanceKlass::get_initialization_error(JavaThread* current) { 1157 MutexLocker ml(current, ClassInitError_lock); 1158 if (_initialization_error_table == nullptr) { 1159 return nullptr; 1160 } 1161 OopHandle* h = _initialization_error_table->get(this); 1162 return (h != nullptr) ? h->resolve() : nullptr; 1163 } 1164 1165 // Need to remove entries for unloaded classes. 1166 void InstanceKlass::clean_initialization_error_table() { 1167 struct InitErrorTableCleaner { 1168 bool do_entry(const InstanceKlass* ik, OopHandle h) { 1169 if (!ik->is_loader_alive()) { 1170 h.release(Universe::vm_global()); 1171 return true; 1172 } else { 1173 return false; 1174 } 1175 } 1176 }; 1177 1178 assert_locked_or_safepoint(ClassInitError_lock); 1179 InitErrorTableCleaner cleaner; 1180 if (_initialization_error_table != nullptr) { 1181 _initialization_error_table->unlink(&cleaner); 1182 } 1183 } 1184 1185 void InstanceKlass::initialize_impl(TRAPS) { 1186 HandleMark hm(THREAD); 1187 1188 // Make sure klass is linked (verified) before initialization 1189 // A class could already be verified, since it has been reflected upon. 1190 link_class(CHECK); 1191 1192 DTRACE_CLASSINIT_PROBE(required, -1); 1193 1194 bool wait = false; 1195 1196 JavaThread* jt = THREAD; 1197 1198 bool debug_logging_enabled = log_is_enabled(Debug, class, init); 1199 1200 // refer to the JVM book page 47 for description of steps 1201 // Step 1 1202 { 1203 Handle h_init_lock(THREAD, init_lock()); 1204 ObjectLocker ol(h_init_lock, CHECK_PREEMPTABLE); 1205 1206 // Step 2 1207 // If we were to use wait() instead of waitInterruptibly() then 1208 // we might end up throwing IE from link/symbol resolution sites 1209 // that aren't expected to throw. This would wreak havoc. See 6320309. 1210 while (is_being_initialized() && !is_reentrant_initialization(jt)) { 1211 if (debug_logging_enabled) { 1212 ResourceMark rm(jt); 1213 log_debug(class, init)("Thread \"%s\" waiting for initialization of %s by thread \"%s\"", 1214 jt->name(), external_name(), init_thread_name()); 1215 } 1216 wait = true; 1217 jt->set_class_to_be_initialized(this); 1218 ol.wait_uninterruptibly(CHECK_PREEMPTABLE); 1219 jt->set_class_to_be_initialized(nullptr); 1220 } 1221 1222 // Step 3 1223 if (is_being_initialized() && is_reentrant_initialization(jt)) { 1224 if (debug_logging_enabled) { 1225 ResourceMark rm(jt); 1226 log_debug(class, init)("Thread \"%s\" recursively initializing %s", 1227 jt->name(), external_name()); 1228 } 1229 DTRACE_CLASSINIT_PROBE_WAIT(recursive, -1, wait); 1230 return; 1231 } 1232 1233 // Step 4 1234 if (is_initialized()) { 1235 if (debug_logging_enabled) { 1236 ResourceMark rm(jt); 1237 log_debug(class, init)("Thread \"%s\" found %s already initialized", 1238 jt->name(), external_name()); 1239 } 1240 DTRACE_CLASSINIT_PROBE_WAIT(concurrent, -1, wait); 1241 return; 1242 } 1243 1244 // Step 5 1245 if (is_in_error_state()) { 1246 if (debug_logging_enabled) { 1247 ResourceMark rm(jt); 1248 log_debug(class, init)("Thread \"%s\" found %s is in error state", 1249 jt->name(), external_name()); 1250 } 1251 1252 DTRACE_CLASSINIT_PROBE_WAIT(erroneous, -1, wait); 1253 ResourceMark rm(THREAD); 1254 Handle cause(THREAD, get_initialization_error(THREAD)); 1255 1256 stringStream ss; 1257 ss.print("Could not initialize class %s", external_name()); 1258 if (cause.is_null()) { 1259 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), ss.as_string()); 1260 } else { 1261 THROW_MSG_CAUSE(vmSymbols::java_lang_NoClassDefFoundError(), 1262 ss.as_string(), cause); 1263 } 1264 } else { 1265 1266 // Step 6 1267 set_init_state(being_initialized); 1268 set_init_thread(jt); 1269 if (debug_logging_enabled) { 1270 ResourceMark rm(jt); 1271 log_debug(class, init)("Thread \"%s\" is initializing %s", 1272 jt->name(), external_name()); 1273 } 1274 } 1275 } 1276 1277 // Block preemption once we are the initializer thread. 1278 // Unmounting now would complicate the reentrant case. 1279 NoPreemptMark npm(THREAD); 1280 1281 // Step 7 1282 // Next, if C is a class rather than an interface, initialize it's super class and super 1283 // interfaces. 1284 if (!is_interface()) { 1285 Klass* super_klass = super(); 1286 if (super_klass != nullptr && super_klass->should_be_initialized()) { 1287 super_klass->initialize(THREAD); 1288 } 1289 // If C implements any interface that declares a non-static, concrete method, 1290 // the initialization of C triggers initialization of its super interfaces. 1291 // Only need to recurse if has_nonstatic_concrete_methods which includes declaring and 1292 // having a superinterface that declares, non-static, concrete methods 1293 if (!HAS_PENDING_EXCEPTION && has_nonstatic_concrete_methods()) { 1294 initialize_super_interfaces(THREAD); 1295 } 1296 1297 // If any exceptions, complete abruptly, throwing the same exception as above. 1298 if (HAS_PENDING_EXCEPTION) { 1299 Handle e(THREAD, PENDING_EXCEPTION); 1300 CLEAR_PENDING_EXCEPTION; 1301 { 1302 EXCEPTION_MARK; 1303 add_initialization_error(THREAD, e); 1304 // Locks object, set state, and notify all waiting threads 1305 set_initialization_state_and_notify(initialization_error, THREAD); 1306 CLEAR_PENDING_EXCEPTION; 1307 } 1308 DTRACE_CLASSINIT_PROBE_WAIT(super__failed, -1, wait); 1309 THROW_OOP(e()); 1310 } 1311 } 1312 1313 1314 // Step 8 1315 { 1316 DTRACE_CLASSINIT_PROBE_WAIT(clinit, -1, wait); 1317 if (class_initializer() != nullptr) { 1318 // Timer includes any side effects of class initialization (resolution, 1319 // etc), but not recursive entry into call_class_initializer(). 1320 PerfClassTraceTime timer(ClassLoader::perf_class_init_time(), 1321 ClassLoader::perf_class_init_selftime(), 1322 ClassLoader::perf_classes_inited(), 1323 jt->get_thread_stat()->perf_recursion_counts_addr(), 1324 jt->get_thread_stat()->perf_timers_addr(), 1325 PerfClassTraceTime::CLASS_CLINIT); 1326 call_class_initializer(THREAD); 1327 } else { 1328 // The elapsed time is so small it's not worth counting. 1329 if (UsePerfData) { 1330 ClassLoader::perf_classes_inited()->inc(); 1331 } 1332 call_class_initializer(THREAD); 1333 } 1334 } 1335 1336 // Step 9 1337 if (!HAS_PENDING_EXCEPTION) { 1338 set_initialization_state_and_notify(fully_initialized, CHECK); 1339 DEBUG_ONLY(vtable().verify(tty, true);) 1340 CompilationPolicy::replay_training_at_init(this, THREAD); 1341 } 1342 else { 1343 // Step 10 and 11 1344 Handle e(THREAD, PENDING_EXCEPTION); 1345 CLEAR_PENDING_EXCEPTION; 1346 // JVMTI has already reported the pending exception 1347 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError 1348 JvmtiExport::clear_detected_exception(jt); 1349 { 1350 EXCEPTION_MARK; 1351 add_initialization_error(THREAD, e); 1352 set_initialization_state_and_notify(initialization_error, THREAD); 1353 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, class initialization error is thrown below 1354 // JVMTI has already reported the pending exception 1355 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError 1356 JvmtiExport::clear_detected_exception(jt); 1357 } 1358 DTRACE_CLASSINIT_PROBE_WAIT(error, -1, wait); 1359 if (e->is_a(vmClasses::Error_klass())) { 1360 THROW_OOP(e()); 1361 } else { 1362 JavaCallArguments args(e); 1363 THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(), 1364 vmSymbols::throwable_void_signature(), 1365 &args); 1366 } 1367 } 1368 DTRACE_CLASSINIT_PROBE_WAIT(end, -1, wait); 1369 } 1370 1371 1372 void InstanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) { 1373 Handle h_init_lock(THREAD, init_lock()); 1374 if (h_init_lock() != nullptr) { 1375 ObjectLocker ol(h_init_lock, THREAD); 1376 set_init_thread(nullptr); // reset _init_thread before changing _init_state 1377 set_init_state(state); 1378 ol.notify_all(CHECK); 1379 } else { 1380 assert(h_init_lock() != nullptr, "The initialization state should never be set twice"); 1381 set_init_thread(nullptr); // reset _init_thread before changing _init_state 1382 set_init_state(state); 1383 } 1384 } 1385 1386 // Update hierarchy. This is done before the new klass has been added to the SystemDictionary. The Compile_lock 1387 // is grabbed, to ensure that the compiler is not using the class hierarchy. 1388 void InstanceKlass::add_to_hierarchy(JavaThread* current) { 1389 assert(!SafepointSynchronize::is_at_safepoint(), "must NOT be at safepoint"); 1390 1391 DeoptimizationScope deopt_scope; 1392 { 1393 MutexLocker ml(current, Compile_lock); 1394 1395 set_init_state(InstanceKlass::loaded); 1396 // make sure init_state store is already done. 1397 // The compiler reads the hierarchy outside of the Compile_lock. 1398 // Access ordering is used to add to hierarchy. 1399 1400 // Link into hierarchy. 1401 append_to_sibling_list(); // add to superklass/sibling list 1402 process_interfaces(); // handle all "implements" declarations 1403 1404 // Now mark all code that depended on old class hierarchy. 1405 // Note: must be done *after* linking k into the hierarchy (was bug 12/9/97) 1406 if (Universe::is_fully_initialized()) { 1407 CodeCache::mark_dependents_on(&deopt_scope, this); 1408 } 1409 } 1410 // Perform the deopt handshake outside Compile_lock. 1411 deopt_scope.deoptimize_marked(); 1412 } 1413 1414 1415 InstanceKlass* InstanceKlass::implementor() const { 1416 InstanceKlass* volatile* ik = adr_implementor(); 1417 if (ik == nullptr) { 1418 return nullptr; 1419 } else { 1420 // This load races with inserts, and therefore needs acquire. 1421 InstanceKlass* ikls = Atomic::load_acquire(ik); 1422 if (ikls != nullptr && !ikls->is_loader_alive()) { 1423 return nullptr; // don't return unloaded class 1424 } else { 1425 return ikls; 1426 } 1427 } 1428 } 1429 1430 1431 void InstanceKlass::set_implementor(InstanceKlass* ik) { 1432 assert_locked_or_safepoint(Compile_lock); 1433 assert(is_interface(), "not interface"); 1434 InstanceKlass* volatile* addr = adr_implementor(); 1435 assert(addr != nullptr, "null addr"); 1436 if (addr != nullptr) { 1437 Atomic::release_store(addr, ik); 1438 } 1439 } 1440 1441 int InstanceKlass::nof_implementors() const { 1442 InstanceKlass* ik = implementor(); 1443 if (ik == nullptr) { 1444 return 0; 1445 } else if (ik != this) { 1446 return 1; 1447 } else { 1448 return 2; 1449 } 1450 } 1451 1452 // The embedded _implementor field can only record one implementor. 1453 // When there are more than one implementors, the _implementor field 1454 // is set to the interface Klass* itself. Following are the possible 1455 // values for the _implementor field: 1456 // null - no implementor 1457 // implementor Klass* - one implementor 1458 // self - more than one implementor 1459 // 1460 // The _implementor field only exists for interfaces. 1461 void InstanceKlass::add_implementor(InstanceKlass* ik) { 1462 if (Universe::is_fully_initialized()) { 1463 assert_lock_strong(Compile_lock); 1464 } 1465 assert(is_interface(), "not interface"); 1466 // Filter out my subinterfaces. 1467 // (Note: Interfaces are never on the subklass list.) 1468 if (ik->is_interface()) return; 1469 1470 // Filter out subclasses whose supers already implement me. 1471 // (Note: CHA must walk subclasses of direct implementors 1472 // in order to locate indirect implementors.) 1473 InstanceKlass* super_ik = ik->java_super(); 1474 if (super_ik != nullptr && super_ik->implements_interface(this)) 1475 // We only need to check one immediate superclass, since the 1476 // implements_interface query looks at transitive_interfaces. 1477 // Any supers of the super have the same (or fewer) transitive_interfaces. 1478 return; 1479 1480 InstanceKlass* iklass = implementor(); 1481 if (iklass == nullptr) { 1482 set_implementor(ik); 1483 } else if (iklass != this && iklass != ik) { 1484 // There is already an implementor. Use itself as an indicator of 1485 // more than one implementors. 1486 set_implementor(this); 1487 } 1488 1489 // The implementor also implements the transitive_interfaces 1490 for (int index = 0; index < local_interfaces()->length(); index++) { 1491 local_interfaces()->at(index)->add_implementor(ik); 1492 } 1493 } 1494 1495 void InstanceKlass::init_implementor() { 1496 if (is_interface()) { 1497 set_implementor(nullptr); 1498 } 1499 } 1500 1501 1502 void InstanceKlass::process_interfaces() { 1503 // link this class into the implementors list of every interface it implements 1504 for (int i = local_interfaces()->length() - 1; i >= 0; i--) { 1505 assert(local_interfaces()->at(i)->is_klass(), "must be a klass"); 1506 InstanceKlass* interf = local_interfaces()->at(i); 1507 assert(interf->is_interface(), "expected interface"); 1508 interf->add_implementor(this); 1509 } 1510 } 1511 1512 bool InstanceKlass::can_be_primary_super_slow() const { 1513 if (is_interface()) 1514 return false; 1515 else 1516 return Klass::can_be_primary_super_slow(); 1517 } 1518 1519 GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots, 1520 Array<InstanceKlass*>* transitive_interfaces) { 1521 // The secondaries are the implemented interfaces. 1522 // We need the cast because Array<Klass*> is NOT a supertype of Array<InstanceKlass*>, 1523 // (but it's safe to do here because we won't write into _secondary_supers from this point on). 1524 Array<Klass*>* interfaces = (Array<Klass*>*)(address)transitive_interfaces; 1525 int num_secondaries = num_extra_slots + interfaces->length(); 1526 if (num_secondaries == 0) { 1527 // Must share this for correct bootstrapping! 1528 set_secondary_supers(Universe::the_empty_klass_array(), Universe::the_empty_klass_bitmap()); 1529 return nullptr; 1530 } else if (num_extra_slots == 0 && interfaces->length() <= 1) { 1531 // We will reuse the transitive interfaces list if we're certain 1532 // it's in hash order. 1533 uintx bitmap = compute_secondary_supers_bitmap(interfaces); 1534 set_secondary_supers(interfaces, bitmap); 1535 return nullptr; 1536 } 1537 // Copy transitive interfaces to a temporary growable array to be constructed 1538 // into the secondary super list with extra slots. 1539 GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length()); 1540 for (int i = 0; i < interfaces->length(); i++) { 1541 secondaries->push(interfaces->at(i)); 1542 } 1543 return secondaries; 1544 } 1545 1546 bool InstanceKlass::implements_interface(Klass* k) const { 1547 if (this == k) return true; 1548 assert(k->is_interface(), "should be an interface class"); 1549 for (int i = 0; i < transitive_interfaces()->length(); i++) { 1550 if (transitive_interfaces()->at(i) == k) { 1551 return true; 1552 } 1553 } 1554 return false; 1555 } 1556 1557 bool InstanceKlass::is_same_or_direct_interface(Klass *k) const { 1558 // Verify direct super interface 1559 if (this == k) return true; 1560 assert(k->is_interface(), "should be an interface class"); 1561 for (int i = 0; i < local_interfaces()->length(); i++) { 1562 if (local_interfaces()->at(i) == k) { 1563 return true; 1564 } 1565 } 1566 return false; 1567 } 1568 1569 objArrayOop InstanceKlass::allocate_objArray(int n, int length, TRAPS) { 1570 check_array_allocation_length(length, arrayOopDesc::max_array_length(T_OBJECT), CHECK_NULL); 1571 size_t size = objArrayOopDesc::object_size(length); 1572 ArrayKlass* ak = array_klass(n, CHECK_NULL); 1573 objArrayOop o = (objArrayOop)Universe::heap()->array_allocate(ak, size, length, 1574 /* do_zero */ true, CHECK_NULL); 1575 return o; 1576 } 1577 1578 instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) { 1579 if (TraceFinalizerRegistration) { 1580 tty->print("Registered "); 1581 i->print_value_on(tty); 1582 tty->print_cr(" (" PTR_FORMAT ") as finalizable", p2i(i)); 1583 } 1584 instanceHandle h_i(THREAD, i); 1585 // Pass the handle as argument, JavaCalls::call expects oop as jobjects 1586 JavaValue result(T_VOID); 1587 JavaCallArguments args(h_i); 1588 methodHandle mh(THREAD, Universe::finalizer_register_method()); 1589 JavaCalls::call(&result, mh, &args, CHECK_NULL); 1590 MANAGEMENT_ONLY(FinalizerService::on_register(h_i(), THREAD);) 1591 return h_i(); 1592 } 1593 1594 instanceOop InstanceKlass::allocate_instance(TRAPS) { 1595 assert(!is_abstract() && !is_interface(), "Should not create this object"); 1596 size_t size = size_helper(); // Query before forming handle. 1597 return (instanceOop)Universe::heap()->obj_allocate(this, size, CHECK_NULL); 1598 } 1599 1600 instanceOop InstanceKlass::allocate_instance(oop java_class, TRAPS) { 1601 Klass* k = java_lang_Class::as_Klass(java_class); 1602 if (k == nullptr) { 1603 ResourceMark rm(THREAD); 1604 THROW_(vmSymbols::java_lang_InstantiationException(), nullptr); 1605 } 1606 InstanceKlass* ik = cast(k); 1607 ik->check_valid_for_instantiation(false, CHECK_NULL); 1608 ik->initialize(CHECK_NULL); 1609 return ik->allocate_instance(THREAD); 1610 } 1611 1612 instanceHandle InstanceKlass::allocate_instance_handle(TRAPS) { 1613 return instanceHandle(THREAD, allocate_instance(THREAD)); 1614 } 1615 1616 void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) { 1617 if (is_interface() || is_abstract()) { 1618 ResourceMark rm(THREAD); 1619 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError() 1620 : vmSymbols::java_lang_InstantiationException(), external_name()); 1621 } 1622 if (this == vmClasses::Class_klass()) { 1623 ResourceMark rm(THREAD); 1624 THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError() 1625 : vmSymbols::java_lang_IllegalAccessException(), external_name()); 1626 } 1627 } 1628 1629 ArrayKlass* InstanceKlass::array_klass(int n, TRAPS) { 1630 // Need load-acquire for lock-free read 1631 if (array_klasses_acquire() == nullptr) { 1632 1633 // Recursively lock array allocation 1634 RecursiveLocker rl(MultiArray_lock, THREAD); 1635 1636 // Check if another thread created the array klass while we were waiting for the lock. 1637 if (array_klasses() == nullptr) { 1638 ObjArrayKlass* k = ObjArrayKlass::allocate_objArray_klass(class_loader_data(), 1, this, CHECK_NULL); 1639 // use 'release' to pair with lock-free load 1640 release_set_array_klasses(k); 1641 } 1642 } 1643 1644 // array_klasses() will always be set at this point 1645 ObjArrayKlass* ak = array_klasses(); 1646 assert(ak != nullptr, "should be set"); 1647 return ak->array_klass(n, THREAD); 1648 } 1649 1650 ArrayKlass* InstanceKlass::array_klass_or_null(int n) { 1651 // Need load-acquire for lock-free read 1652 ObjArrayKlass* oak = array_klasses_acquire(); 1653 if (oak == nullptr) { 1654 return nullptr; 1655 } else { 1656 return oak->array_klass_or_null(n); 1657 } 1658 } 1659 1660 ArrayKlass* InstanceKlass::array_klass(TRAPS) { 1661 return array_klass(1, THREAD); 1662 } 1663 1664 ArrayKlass* InstanceKlass::array_klass_or_null() { 1665 return array_klass_or_null(1); 1666 } 1667 1668 static int call_class_initializer_counter = 0; // for debugging 1669 1670 Method* InstanceKlass::class_initializer() const { 1671 Method* clinit = find_method( 1672 vmSymbols::class_initializer_name(), vmSymbols::void_method_signature()); 1673 if (clinit != nullptr && clinit->has_valid_initializer_flags()) { 1674 return clinit; 1675 } 1676 return nullptr; 1677 } 1678 1679 void InstanceKlass::call_class_initializer(TRAPS) { 1680 if (ReplayCompiles && 1681 (ReplaySuppressInitializers == 1 || 1682 (ReplaySuppressInitializers >= 2 && class_loader() != nullptr))) { 1683 // Hide the existence of the initializer for the purpose of replaying the compile 1684 return; 1685 } 1686 1687 #if INCLUDE_CDS 1688 // This is needed to ensure the consistency of the archived heap objects. 1689 if (has_aot_initialized_mirror() && CDSConfig::is_loading_heap()) { 1690 AOTClassInitializer::call_runtime_setup(THREAD, this); 1691 return; 1692 } else if (has_archived_enum_objs()) { 1693 assert(is_shared(), "must be"); 1694 bool initialized = CDSEnumKlass::initialize_enum_klass(this, CHECK); 1695 if (initialized) { 1696 return; 1697 } 1698 } 1699 #endif 1700 1701 methodHandle h_method(THREAD, class_initializer()); 1702 assert(!is_initialized(), "we cannot initialize twice"); 1703 LogTarget(Info, class, init) lt; 1704 if (lt.is_enabled()) { 1705 ResourceMark rm(THREAD); 1706 LogStream ls(lt); 1707 ls.print("%d Initializing ", call_class_initializer_counter++); 1708 name()->print_value_on(&ls); 1709 ls.print_cr("%s (" PTR_FORMAT ") by thread \"%s\"", 1710 h_method() == nullptr ? "(no method)" : "", p2i(this), 1711 THREAD->name()); 1712 } 1713 if (h_method() != nullptr) { 1714 ThreadInClassInitializer ticl(THREAD, this); // Track class being initialized 1715 JavaCallArguments args; // No arguments 1716 JavaValue result(T_VOID); 1717 JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args) 1718 } 1719 } 1720 1721 // If a class that implements this interface is initialized, is the JVM required 1722 // to first execute a <clinit> method declared in this interface, 1723 // or (if also_check_supers==true) any of the super types of this interface? 1724 // 1725 // JVMS 5.5. Initialization, step 7: Next, if C is a class rather than 1726 // an interface, then let SC be its superclass and let SI1, ..., SIn 1727 // be all superinterfaces of C (whether direct or indirect) that 1728 // declare at least one non-abstract, non-static method. 1729 // 1730 // So when an interface is initialized, it does not look at its 1731 // supers. But a proper class will ensure that all of its supers have 1732 // run their <clinit> methods, except that it disregards interfaces 1733 // that lack a non-static concrete method (i.e., a default method). 1734 // Therefore, you should probably call this method only when the 1735 // current class is a super of some proper class, not an interface. 1736 bool InstanceKlass::interface_needs_clinit_execution_as_super(bool also_check_supers) const { 1737 assert(is_interface(), "must be"); 1738 1739 if (!has_nonstatic_concrete_methods()) { 1740 // quick check: no nonstatic concrete methods are declared by this or any super interfaces 1741 return false; 1742 } 1743 1744 // JVMS 5.5. Initialization 1745 // ...If C is an interface that declares a non-abstract, 1746 // non-static method, the initialization of a class that 1747 // implements C directly or indirectly. 1748 if (declares_nonstatic_concrete_methods() && class_initializer() != nullptr) { 1749 return true; 1750 } 1751 if (also_check_supers) { 1752 Array<InstanceKlass*>* all_ifs = transitive_interfaces(); 1753 for (int i = 0; i < all_ifs->length(); ++i) { 1754 InstanceKlass* super_intf = all_ifs->at(i); 1755 if (super_intf->declares_nonstatic_concrete_methods() && super_intf->class_initializer() != nullptr) { 1756 return true; 1757 } 1758 } 1759 } 1760 return false; 1761 } 1762 1763 void InstanceKlass::mask_for(const methodHandle& method, int bci, 1764 InterpreterOopMap* entry_for) { 1765 // Lazily create the _oop_map_cache at first request. 1766 // Load_acquire is needed to safely get instance published with CAS by another thread. 1767 OopMapCache* oop_map_cache = Atomic::load_acquire(&_oop_map_cache); 1768 if (oop_map_cache == nullptr) { 1769 // Try to install new instance atomically. 1770 oop_map_cache = new OopMapCache(); 1771 OopMapCache* other = Atomic::cmpxchg(&_oop_map_cache, (OopMapCache*)nullptr, oop_map_cache); 1772 if (other != nullptr) { 1773 // Someone else managed to install before us, ditch local copy and use the existing one. 1774 delete oop_map_cache; 1775 oop_map_cache = other; 1776 } 1777 } 1778 // _oop_map_cache is constant after init; lookup below does its own locking. 1779 oop_map_cache->lookup(method, bci, entry_for); 1780 } 1781 1782 bool InstanceKlass::contains_field_offset(int offset) { 1783 fieldDescriptor fd; 1784 return find_field_from_offset(offset, false, &fd); 1785 } 1786 1787 FieldInfo InstanceKlass::field(int index) const { 1788 for (AllFieldStream fs(this); !fs.done(); fs.next()) { 1789 if (fs.index() == index) { 1790 return fs.to_FieldInfo(); 1791 } 1792 } 1793 fatal("Field not found"); 1794 return FieldInfo(); 1795 } 1796 1797 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const { 1798 JavaFieldStream fs(this); 1799 if (fs.lookup(name, sig)) { 1800 assert(fs.name() == name, "name must match"); 1801 assert(fs.signature() == sig, "signature must match"); 1802 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.to_FieldInfo()); 1803 return true; 1804 } 1805 return false; 1806 } 1807 1808 1809 Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const { 1810 const int n = local_interfaces()->length(); 1811 for (int i = 0; i < n; i++) { 1812 Klass* intf1 = local_interfaces()->at(i); 1813 assert(intf1->is_interface(), "just checking type"); 1814 // search for field in current interface 1815 if (InstanceKlass::cast(intf1)->find_local_field(name, sig, fd)) { 1816 assert(fd->is_static(), "interface field must be static"); 1817 return intf1; 1818 } 1819 // search for field in direct superinterfaces 1820 Klass* intf2 = InstanceKlass::cast(intf1)->find_interface_field(name, sig, fd); 1821 if (intf2 != nullptr) return intf2; 1822 } 1823 // otherwise field lookup fails 1824 return nullptr; 1825 } 1826 1827 1828 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const { 1829 // search order according to newest JVM spec (5.4.3.2, p.167). 1830 // 1) search for field in current klass 1831 if (find_local_field(name, sig, fd)) { 1832 return const_cast<InstanceKlass*>(this); 1833 } 1834 // 2) search for field recursively in direct superinterfaces 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 { Klass* supr = super(); 1840 if (supr != nullptr) return InstanceKlass::cast(supr)->find_field(name, sig, fd); 1841 } 1842 // 4) otherwise field lookup fails 1843 return nullptr; 1844 } 1845 1846 1847 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const { 1848 // search order according to newest JVM spec (5.4.3.2, p.167). 1849 // 1) search for field in current klass 1850 if (find_local_field(name, sig, fd)) { 1851 if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this); 1852 } 1853 // 2) search for field recursively in direct superinterfaces 1854 if (is_static) { 1855 Klass* intf = find_interface_field(name, sig, fd); 1856 if (intf != nullptr) return intf; 1857 } 1858 // 3) apply field lookup recursively if superclass exists 1859 { Klass* supr = super(); 1860 if (supr != nullptr) return InstanceKlass::cast(supr)->find_field(name, sig, is_static, fd); 1861 } 1862 // 4) otherwise field lookup fails 1863 return nullptr; 1864 } 1865 1866 1867 bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const { 1868 for (JavaFieldStream fs(this); !fs.done(); fs.next()) { 1869 if (fs.offset() == offset) { 1870 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.to_FieldInfo()); 1871 if (fd->is_static() == is_static) return true; 1872 } 1873 } 1874 return false; 1875 } 1876 1877 1878 bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const { 1879 Klass* klass = const_cast<InstanceKlass*>(this); 1880 while (klass != nullptr) { 1881 if (InstanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) { 1882 return true; 1883 } 1884 klass = klass->super(); 1885 } 1886 return false; 1887 } 1888 1889 1890 void InstanceKlass::methods_do(void f(Method* method)) { 1891 // Methods aren't stable until they are loaded. This can be read outside 1892 // a lock through the ClassLoaderData for profiling 1893 // Redefined scratch classes are on the list and need to be cleaned 1894 if (!is_loaded() && !is_scratch_class()) { 1895 return; 1896 } 1897 1898 int len = methods()->length(); 1899 for (int index = 0; index < len; index++) { 1900 Method* m = methods()->at(index); 1901 assert(m->is_method(), "must be method"); 1902 f(m); 1903 } 1904 } 1905 1906 1907 void InstanceKlass::do_local_static_fields(FieldClosure* cl) { 1908 for (JavaFieldStream fs(this); !fs.done(); fs.next()) { 1909 if (fs.access_flags().is_static()) { 1910 fieldDescriptor& fd = fs.field_descriptor(); 1911 cl->do_field(&fd); 1912 } 1913 } 1914 } 1915 1916 1917 void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle mirror, TRAPS) { 1918 for (JavaFieldStream fs(this); !fs.done(); fs.next()) { 1919 if (fs.access_flags().is_static()) { 1920 fieldDescriptor& fd = fs.field_descriptor(); 1921 f(&fd, mirror, CHECK); 1922 } 1923 } 1924 } 1925 1926 void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) { 1927 InstanceKlass* super = superklass(); 1928 if (super != nullptr) { 1929 super->do_nonstatic_fields(cl); 1930 } 1931 for (JavaFieldStream fs(this); !fs.done(); fs.next()) { 1932 fieldDescriptor& fd = fs.field_descriptor(); 1933 if (!fd.is_static()) { 1934 cl->do_field(&fd); 1935 } 1936 } 1937 } 1938 1939 static int compare_fields_by_offset(FieldInfo* a, FieldInfo* b) { 1940 return a->offset() - b->offset(); 1941 } 1942 1943 void InstanceKlass::print_nonstatic_fields(FieldClosure* cl) { 1944 InstanceKlass* super = superklass(); 1945 if (super != nullptr) { 1946 super->print_nonstatic_fields(cl); 1947 } 1948 ResourceMark rm; 1949 // In DebugInfo nonstatic fields are sorted by offset. 1950 GrowableArray<FieldInfo> fields_sorted; 1951 for (AllFieldStream fs(this); !fs.done(); fs.next()) { 1952 if (!fs.access_flags().is_static()) { 1953 fields_sorted.push(fs.to_FieldInfo()); 1954 } 1955 } 1956 int length = fields_sorted.length(); 1957 if (length > 0) { 1958 fields_sorted.sort(compare_fields_by_offset); 1959 fieldDescriptor fd; 1960 for (int i = 0; i < length; i++) { 1961 fd.reinitialize(this, fields_sorted.at(i)); 1962 assert(!fd.is_static() && fd.offset() == checked_cast<int>(fields_sorted.at(i).offset()), "only nonstatic fields"); 1963 cl->do_field(&fd); 1964 } 1965 } 1966 } 1967 1968 #ifdef ASSERT 1969 static int linear_search(const Array<Method*>* methods, 1970 const Symbol* name, 1971 const Symbol* signature) { 1972 const int len = methods->length(); 1973 for (int index = 0; index < len; index++) { 1974 const Method* const m = methods->at(index); 1975 assert(m->is_method(), "must be method"); 1976 if (m->signature() == signature && m->name() == name) { 1977 return index; 1978 } 1979 } 1980 return -1; 1981 } 1982 #endif 1983 1984 bool InstanceKlass::_disable_method_binary_search = false; 1985 1986 NOINLINE int linear_search(const Array<Method*>* methods, const Symbol* name) { 1987 int len = methods->length(); 1988 int l = 0; 1989 int h = len - 1; 1990 while (l <= h) { 1991 Method* m = methods->at(l); 1992 if (m->name() == name) { 1993 return l; 1994 } 1995 l++; 1996 } 1997 return -1; 1998 } 1999 2000 inline int InstanceKlass::quick_search(const Array<Method*>* methods, const Symbol* name) { 2001 if (_disable_method_binary_search) { 2002 assert(CDSConfig::is_dumping_dynamic_archive(), "must be"); 2003 // At the final stage of dynamic dumping, the methods array may not be sorted 2004 // by ascending addresses of their names, so we can't use binary search anymore. 2005 // However, methods with the same name are still laid out consecutively inside the 2006 // methods array, so let's look for the first one that matches. 2007 return linear_search(methods, name); 2008 } 2009 2010 int len = methods->length(); 2011 int l = 0; 2012 int h = len - 1; 2013 2014 // methods are sorted by ascending addresses of their names, so do binary search 2015 while (l <= h) { 2016 int mid = (l + h) >> 1; 2017 Method* m = methods->at(mid); 2018 assert(m->is_method(), "must be method"); 2019 int res = m->name()->fast_compare(name); 2020 if (res == 0) { 2021 return mid; 2022 } else if (res < 0) { 2023 l = mid + 1; 2024 } else { 2025 h = mid - 1; 2026 } 2027 } 2028 return -1; 2029 } 2030 2031 // find_method looks up the name/signature in the local methods array 2032 Method* InstanceKlass::find_method(const Symbol* name, 2033 const Symbol* signature) const { 2034 return find_method_impl(name, signature, 2035 OverpassLookupMode::find, 2036 StaticLookupMode::find, 2037 PrivateLookupMode::find); 2038 } 2039 2040 Method* InstanceKlass::find_method_impl(const Symbol* name, 2041 const Symbol* signature, 2042 OverpassLookupMode overpass_mode, 2043 StaticLookupMode static_mode, 2044 PrivateLookupMode private_mode) const { 2045 return InstanceKlass::find_method_impl(methods(), 2046 name, 2047 signature, 2048 overpass_mode, 2049 static_mode, 2050 private_mode); 2051 } 2052 2053 // find_instance_method looks up the name/signature in the local methods array 2054 // and skips over static methods 2055 Method* InstanceKlass::find_instance_method(const Array<Method*>* methods, 2056 const Symbol* name, 2057 const Symbol* signature, 2058 PrivateLookupMode private_mode) { 2059 Method* const meth = InstanceKlass::find_method_impl(methods, 2060 name, 2061 signature, 2062 OverpassLookupMode::find, 2063 StaticLookupMode::skip, 2064 private_mode); 2065 assert(((meth == nullptr) || !meth->is_static()), 2066 "find_instance_method should have skipped statics"); 2067 return meth; 2068 } 2069 2070 // find_instance_method looks up the name/signature in the local methods array 2071 // and skips over static methods 2072 Method* InstanceKlass::find_instance_method(const Symbol* name, 2073 const Symbol* signature, 2074 PrivateLookupMode private_mode) const { 2075 return InstanceKlass::find_instance_method(methods(), name, signature, private_mode); 2076 } 2077 2078 // Find looks up the name/signature in the local methods array 2079 // and filters on the overpass, static and private flags 2080 // This returns the first one found 2081 // note that the local methods array can have up to one overpass, one static 2082 // and one instance (private or not) with the same name/signature 2083 Method* InstanceKlass::find_local_method(const Symbol* name, 2084 const Symbol* signature, 2085 OverpassLookupMode overpass_mode, 2086 StaticLookupMode static_mode, 2087 PrivateLookupMode private_mode) const { 2088 return InstanceKlass::find_method_impl(methods(), 2089 name, 2090 signature, 2091 overpass_mode, 2092 static_mode, 2093 private_mode); 2094 } 2095 2096 // Find looks up the name/signature in the local methods array 2097 // and filters on the overpass, static and private flags 2098 // This returns the first one found 2099 // note that the local methods array can have up to one overpass, one static 2100 // and one instance (private or not) with the same name/signature 2101 Method* InstanceKlass::find_local_method(const Array<Method*>* methods, 2102 const Symbol* name, 2103 const Symbol* signature, 2104 OverpassLookupMode overpass_mode, 2105 StaticLookupMode static_mode, 2106 PrivateLookupMode private_mode) { 2107 return InstanceKlass::find_method_impl(methods, 2108 name, 2109 signature, 2110 overpass_mode, 2111 static_mode, 2112 private_mode); 2113 } 2114 2115 Method* InstanceKlass::find_method(const Array<Method*>* methods, 2116 const Symbol* name, 2117 const Symbol* signature) { 2118 return InstanceKlass::find_method_impl(methods, 2119 name, 2120 signature, 2121 OverpassLookupMode::find, 2122 StaticLookupMode::find, 2123 PrivateLookupMode::find); 2124 } 2125 2126 Method* InstanceKlass::find_method_impl(const Array<Method*>* methods, 2127 const Symbol* name, 2128 const Symbol* signature, 2129 OverpassLookupMode overpass_mode, 2130 StaticLookupMode static_mode, 2131 PrivateLookupMode private_mode) { 2132 int hit = find_method_index(methods, name, signature, overpass_mode, static_mode, private_mode); 2133 return hit >= 0 ? methods->at(hit): nullptr; 2134 } 2135 2136 // true if method matches signature and conforms to skipping_X conditions. 2137 static bool method_matches(const Method* m, 2138 const Symbol* signature, 2139 bool skipping_overpass, 2140 bool skipping_static, 2141 bool skipping_private) { 2142 return ((m->signature() == signature) && 2143 (!skipping_overpass || !m->is_overpass()) && 2144 (!skipping_static || !m->is_static()) && 2145 (!skipping_private || !m->is_private())); 2146 } 2147 2148 // Used directly for default_methods to find the index into the 2149 // default_vtable_indices, and indirectly by find_method 2150 // find_method_index looks in the local methods array to return the index 2151 // of the matching name/signature. If, overpass methods are being ignored, 2152 // the search continues to find a potential non-overpass match. This capability 2153 // is important during method resolution to prefer a static method, for example, 2154 // over an overpass method. 2155 // There is the possibility in any _method's array to have the same name/signature 2156 // for a static method, an overpass method and a local instance method 2157 // To correctly catch a given method, the search criteria may need 2158 // to explicitly skip the other two. For local instance methods, it 2159 // is often necessary to skip private methods 2160 int InstanceKlass::find_method_index(const Array<Method*>* methods, 2161 const Symbol* name, 2162 const Symbol* signature, 2163 OverpassLookupMode overpass_mode, 2164 StaticLookupMode static_mode, 2165 PrivateLookupMode private_mode) { 2166 const bool skipping_overpass = (overpass_mode == OverpassLookupMode::skip); 2167 const bool skipping_static = (static_mode == StaticLookupMode::skip); 2168 const bool skipping_private = (private_mode == PrivateLookupMode::skip); 2169 const int hit = quick_search(methods, name); 2170 if (hit != -1) { 2171 const Method* const m = methods->at(hit); 2172 2173 // Do linear search to find matching signature. First, quick check 2174 // for common case, ignoring overpasses if requested. 2175 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) { 2176 return hit; 2177 } 2178 2179 // search downwards through overloaded methods 2180 int i; 2181 for (i = hit - 1; i >= 0; --i) { 2182 const Method* const m = methods->at(i); 2183 assert(m->is_method(), "must be method"); 2184 if (m->name() != name) { 2185 break; 2186 } 2187 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) { 2188 return i; 2189 } 2190 } 2191 // search upwards 2192 for (i = hit + 1; i < methods->length(); ++i) { 2193 const Method* const m = methods->at(i); 2194 assert(m->is_method(), "must be method"); 2195 if (m->name() != name) { 2196 break; 2197 } 2198 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) { 2199 return i; 2200 } 2201 } 2202 // not found 2203 #ifdef ASSERT 2204 const int index = (skipping_overpass || skipping_static || skipping_private) ? -1 : 2205 linear_search(methods, name, signature); 2206 assert(-1 == index, "binary search should have found entry %d", index); 2207 #endif 2208 } 2209 return -1; 2210 } 2211 2212 int InstanceKlass::find_method_by_name(const Symbol* name, int* end) const { 2213 return find_method_by_name(methods(), name, end); 2214 } 2215 2216 int InstanceKlass::find_method_by_name(const Array<Method*>* methods, 2217 const Symbol* name, 2218 int* end_ptr) { 2219 assert(end_ptr != nullptr, "just checking"); 2220 int start = quick_search(methods, name); 2221 int end = start + 1; 2222 if (start != -1) { 2223 while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start; 2224 while (end < methods->length() && (methods->at(end))->name() == name) ++end; 2225 *end_ptr = end; 2226 return start; 2227 } 2228 return -1; 2229 } 2230 2231 // uncached_lookup_method searches both the local class methods array and all 2232 // superclasses methods arrays, skipping any overpass methods in superclasses, 2233 // and possibly skipping private methods. 2234 Method* InstanceKlass::uncached_lookup_method(const Symbol* name, 2235 const Symbol* signature, 2236 OverpassLookupMode overpass_mode, 2237 PrivateLookupMode private_mode) const { 2238 OverpassLookupMode overpass_local_mode = overpass_mode; 2239 const Klass* klass = this; 2240 while (klass != nullptr) { 2241 Method* const method = InstanceKlass::cast(klass)->find_method_impl(name, 2242 signature, 2243 overpass_local_mode, 2244 StaticLookupMode::find, 2245 private_mode); 2246 if (method != nullptr) { 2247 return method; 2248 } 2249 klass = klass->super(); 2250 overpass_local_mode = OverpassLookupMode::skip; // Always ignore overpass methods in superclasses 2251 } 2252 return nullptr; 2253 } 2254 2255 #ifdef ASSERT 2256 // search through class hierarchy and return true if this class or 2257 // one of the superclasses was redefined 2258 bool InstanceKlass::has_redefined_this_or_super() const { 2259 const Klass* klass = this; 2260 while (klass != nullptr) { 2261 if (InstanceKlass::cast(klass)->has_been_redefined()) { 2262 return true; 2263 } 2264 klass = klass->super(); 2265 } 2266 return false; 2267 } 2268 #endif 2269 2270 // lookup a method in the default methods list then in all transitive interfaces 2271 // Do NOT return private or static methods 2272 Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name, 2273 Symbol* signature) const { 2274 Method* m = nullptr; 2275 if (default_methods() != nullptr) { 2276 m = find_method(default_methods(), name, signature); 2277 } 2278 // Look up interfaces 2279 if (m == nullptr) { 2280 m = lookup_method_in_all_interfaces(name, signature, DefaultsLookupMode::find); 2281 } 2282 return m; 2283 } 2284 2285 // lookup a method in all the interfaces that this class implements 2286 // Do NOT return private or static methods, new in JDK8 which are not externally visible 2287 // They should only be found in the initial InterfaceMethodRef 2288 Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name, 2289 Symbol* signature, 2290 DefaultsLookupMode defaults_mode) const { 2291 Array<InstanceKlass*>* all_ifs = transitive_interfaces(); 2292 int num_ifs = all_ifs->length(); 2293 InstanceKlass *ik = nullptr; 2294 for (int i = 0; i < num_ifs; i++) { 2295 ik = all_ifs->at(i); 2296 Method* m = ik->lookup_method(name, signature); 2297 if (m != nullptr && m->is_public() && !m->is_static() && 2298 ((defaults_mode != DefaultsLookupMode::skip) || !m->is_default_method())) { 2299 return m; 2300 } 2301 } 2302 return nullptr; 2303 } 2304 2305 PrintClassClosure::PrintClassClosure(outputStream* st, bool verbose) 2306 :_st(st), _verbose(verbose) { 2307 ResourceMark rm; 2308 _st->print("%-18s ", "KlassAddr"); 2309 _st->print("%-4s ", "Size"); 2310 _st->print("%-20s ", "State"); 2311 _st->print("%-7s ", "Flags"); 2312 _st->print("%-5s ", "ClassName"); 2313 _st->cr(); 2314 } 2315 2316 void PrintClassClosure::do_klass(Klass* k) { 2317 ResourceMark rm; 2318 // klass pointer 2319 _st->print(PTR_FORMAT " ", p2i(k)); 2320 // klass size 2321 _st->print("%4d ", k->size()); 2322 // initialization state 2323 if (k->is_instance_klass()) { 2324 _st->print("%-20s ",InstanceKlass::cast(k)->init_state_name()); 2325 } else { 2326 _st->print("%-20s ",""); 2327 } 2328 // misc flags(Changes should synced with ClassesDCmd::ClassesDCmd help doc) 2329 char buf[10]; 2330 int i = 0; 2331 if (k->has_finalizer()) buf[i++] = 'F'; 2332 if (k->is_instance_klass()) { 2333 InstanceKlass* ik = InstanceKlass::cast(k); 2334 if (ik->has_final_method()) buf[i++] = 'f'; 2335 if (ik->is_rewritten()) buf[i++] = 'W'; 2336 if (ik->is_contended()) buf[i++] = 'C'; 2337 if (ik->has_been_redefined()) buf[i++] = 'R'; 2338 if (ik->is_shared()) buf[i++] = 'S'; 2339 } 2340 buf[i++] = '\0'; 2341 _st->print("%-7s ", buf); 2342 // klass name 2343 _st->print("%-5s ", k->external_name()); 2344 // end 2345 _st->cr(); 2346 if (_verbose) { 2347 k->print_on(_st); 2348 } 2349 } 2350 2351 /* jni_id_for for jfieldIds only */ 2352 JNIid* InstanceKlass::jni_id_for(int offset) { 2353 MutexLocker ml(JfieldIdCreation_lock); 2354 JNIid* probe = jni_ids() == nullptr ? nullptr : jni_ids()->find(offset); 2355 if (probe == nullptr) { 2356 // Allocate new static field identifier 2357 probe = new JNIid(this, offset, jni_ids()); 2358 set_jni_ids(probe); 2359 } 2360 return probe; 2361 } 2362 2363 u2 InstanceKlass::enclosing_method_data(int offset) const { 2364 const Array<jushort>* const inner_class_list = inner_classes(); 2365 if (inner_class_list == nullptr) { 2366 return 0; 2367 } 2368 const int length = inner_class_list->length(); 2369 if (length % inner_class_next_offset == 0) { 2370 return 0; 2371 } 2372 const int index = length - enclosing_method_attribute_size; 2373 assert(offset < enclosing_method_attribute_size, "invalid offset"); 2374 return inner_class_list->at(index + offset); 2375 } 2376 2377 void InstanceKlass::set_enclosing_method_indices(u2 class_index, 2378 u2 method_index) { 2379 Array<jushort>* inner_class_list = inner_classes(); 2380 assert (inner_class_list != nullptr, "_inner_classes list is not set up"); 2381 int length = inner_class_list->length(); 2382 if (length % inner_class_next_offset == enclosing_method_attribute_size) { 2383 int index = length - enclosing_method_attribute_size; 2384 inner_class_list->at_put( 2385 index + enclosing_method_class_index_offset, class_index); 2386 inner_class_list->at_put( 2387 index + enclosing_method_method_index_offset, method_index); 2388 } 2389 } 2390 2391 jmethodID InstanceKlass::update_jmethod_id(jmethodID* jmeths, Method* method, int idnum) { 2392 if (method->is_old() && !method->is_obsolete()) { 2393 // If the method passed in is old (but not obsolete), use the current version. 2394 method = method_with_idnum((int)idnum); 2395 assert(method != nullptr, "old and but not obsolete, so should exist"); 2396 } 2397 jmethodID new_id = Method::make_jmethod_id(class_loader_data(), method); 2398 Atomic::release_store(&jmeths[idnum + 1], new_id); 2399 return new_id; 2400 } 2401 2402 // Allocate the jmethodID cache. 2403 static jmethodID* create_jmethod_id_cache(size_t size) { 2404 jmethodID* jmeths = NEW_C_HEAP_ARRAY(jmethodID, size + 1, mtClass); 2405 memset(jmeths, 0, (size + 1) * sizeof(jmethodID)); 2406 // cache size is stored in element[0], other elements offset by one 2407 jmeths[0] = (jmethodID)size; 2408 return jmeths; 2409 } 2410 2411 // When reading outside a lock, use this. 2412 jmethodID* InstanceKlass::methods_jmethod_ids_acquire() const { 2413 return Atomic::load_acquire(&_methods_jmethod_ids); 2414 } 2415 2416 void InstanceKlass::release_set_methods_jmethod_ids(jmethodID* jmeths) { 2417 Atomic::release_store(&_methods_jmethod_ids, jmeths); 2418 } 2419 2420 // Lookup or create a jmethodID. 2421 jmethodID InstanceKlass::get_jmethod_id(Method* method) { 2422 int idnum = method->method_idnum(); 2423 jmethodID* jmeths = methods_jmethod_ids_acquire(); 2424 2425 // We use a double-check locking idiom here because this cache is 2426 // performance sensitive. In the normal system, this cache only 2427 // transitions from null to non-null which is safe because we use 2428 // release_set_methods_jmethod_ids() to advertise the new cache. 2429 // A partially constructed cache should never be seen by a racing 2430 // thread. We also use release_store() to save a new jmethodID 2431 // in the cache so a partially constructed jmethodID should never be 2432 // seen either. Cache reads of existing jmethodIDs proceed without a 2433 // lock, but cache writes of a new jmethodID requires uniqueness and 2434 // creation of the cache itself requires no leaks so a lock is 2435 // acquired in those two cases. 2436 // 2437 // If the RedefineClasses() API has been used, then this cache grows 2438 // in the redefinition safepoint. 2439 2440 if (jmeths == nullptr) { 2441 MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag); 2442 jmeths = _methods_jmethod_ids; 2443 // Still null? 2444 if (jmeths == nullptr) { 2445 size_t size = idnum_allocated_count(); 2446 assert(size > (size_t)idnum, "should already have space"); 2447 jmeths = create_jmethod_id_cache(size); 2448 jmethodID new_id = update_jmethod_id(jmeths, method, idnum); 2449 2450 // publish jmeths 2451 release_set_methods_jmethod_ids(jmeths); 2452 return new_id; 2453 } 2454 } 2455 2456 jmethodID id = Atomic::load_acquire(&jmeths[idnum + 1]); 2457 if (id == nullptr) { 2458 MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag); 2459 id = jmeths[idnum + 1]; 2460 // Still null? 2461 if (id == nullptr) { 2462 return update_jmethod_id(jmeths, method, idnum); 2463 } 2464 } 2465 return id; 2466 } 2467 2468 void InstanceKlass::update_methods_jmethod_cache() { 2469 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint"); 2470 jmethodID* cache = _methods_jmethod_ids; 2471 if (cache != nullptr) { 2472 size_t size = idnum_allocated_count(); 2473 size_t old_size = (size_t)cache[0]; 2474 if (old_size < size + 1) { 2475 // Allocate a larger one and copy entries to the new one. 2476 // They've already been updated to point to new methods where applicable (i.e., not obsolete). 2477 jmethodID* new_cache = create_jmethod_id_cache(size); 2478 2479 for (int i = 1; i <= (int)old_size; i++) { 2480 new_cache[i] = cache[i]; 2481 } 2482 _methods_jmethod_ids = new_cache; 2483 FREE_C_HEAP_ARRAY(jmethodID, cache); 2484 } 2485 } 2486 } 2487 2488 // Make a jmethodID for all methods in this class. This makes getting all method 2489 // ids much, much faster with classes with more than 8 2490 // methods, and has a *substantial* effect on performance with jvmti 2491 // code that loads all jmethodIDs for all classes. 2492 void InstanceKlass::make_methods_jmethod_ids() { 2493 MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag); 2494 jmethodID* jmeths = _methods_jmethod_ids; 2495 if (jmeths == nullptr) { 2496 jmeths = create_jmethod_id_cache(idnum_allocated_count()); 2497 release_set_methods_jmethod_ids(jmeths); 2498 } 2499 2500 int length = methods()->length(); 2501 for (int index = 0; index < length; index++) { 2502 Method* m = methods()->at(index); 2503 int idnum = m->method_idnum(); 2504 assert(!m->is_old(), "should not have old methods or I'm confused"); 2505 jmethodID id = Atomic::load_acquire(&jmeths[idnum + 1]); 2506 if (!m->is_overpass() && // skip overpasses 2507 id == nullptr) { 2508 id = Method::make_jmethod_id(class_loader_data(), m); 2509 Atomic::release_store(&jmeths[idnum + 1], id); 2510 } 2511 } 2512 } 2513 2514 // Lookup a jmethodID, null if not found. Do no blocking, no allocations, no handles 2515 jmethodID InstanceKlass::jmethod_id_or_null(Method* method) { 2516 int idnum = method->method_idnum(); 2517 jmethodID* jmeths = methods_jmethod_ids_acquire(); 2518 return (jmeths != nullptr) ? jmeths[idnum + 1] : nullptr; 2519 } 2520 2521 inline DependencyContext InstanceKlass::dependencies() { 2522 DependencyContext dep_context(&_dep_context, &_dep_context_last_cleaned); 2523 return dep_context; 2524 } 2525 2526 void InstanceKlass::mark_dependent_nmethods(DeoptimizationScope* deopt_scope, KlassDepChange& changes) { 2527 dependencies().mark_dependent_nmethods(deopt_scope, changes); 2528 } 2529 2530 void InstanceKlass::add_dependent_nmethod(nmethod* nm) { 2531 assert_lock_strong(CodeCache_lock); 2532 dependencies().add_dependent_nmethod(nm); 2533 } 2534 2535 void InstanceKlass::clean_dependency_context() { 2536 dependencies().clean_unloading_dependents(); 2537 } 2538 2539 #ifndef PRODUCT 2540 void InstanceKlass::print_dependent_nmethods(bool verbose) { 2541 dependencies().print_dependent_nmethods(verbose); 2542 } 2543 2544 bool InstanceKlass::is_dependent_nmethod(nmethod* nm) { 2545 return dependencies().is_dependent_nmethod(nm); 2546 } 2547 #endif //PRODUCT 2548 2549 void InstanceKlass::clean_weak_instanceklass_links() { 2550 clean_implementors_list(); 2551 clean_method_data(); 2552 } 2553 2554 void InstanceKlass::clean_implementors_list() { 2555 assert(is_loader_alive(), "this klass should be live"); 2556 if (is_interface()) { 2557 assert (ClassUnloading, "only called for ClassUnloading"); 2558 for (;;) { 2559 // Use load_acquire due to competing with inserts 2560 InstanceKlass* volatile* iklass = adr_implementor(); 2561 assert(iklass != nullptr, "Klass must not be null"); 2562 InstanceKlass* impl = Atomic::load_acquire(iklass); 2563 if (impl != nullptr && !impl->is_loader_alive()) { 2564 // null this field, might be an unloaded instance klass or null 2565 if (Atomic::cmpxchg(iklass, impl, (InstanceKlass*)nullptr) == impl) { 2566 // Successfully unlinking implementor. 2567 if (log_is_enabled(Trace, class, unload)) { 2568 ResourceMark rm; 2569 log_trace(class, unload)("unlinking class (implementor): %s", impl->external_name()); 2570 } 2571 return; 2572 } 2573 } else { 2574 return; 2575 } 2576 } 2577 } 2578 } 2579 2580 void InstanceKlass::clean_method_data() { 2581 for (int m = 0; m < methods()->length(); m++) { 2582 MethodData* mdo = methods()->at(m)->method_data(); 2583 if (mdo != nullptr) { 2584 mdo->clean_method_data(/*always_clean*/false); 2585 } 2586 } 2587 } 2588 2589 void InstanceKlass::metaspace_pointers_do(MetaspaceClosure* it) { 2590 Klass::metaspace_pointers_do(it); 2591 2592 if (log_is_enabled(Trace, aot)) { 2593 ResourceMark rm; 2594 log_trace(aot)("Iter(InstanceKlass): %p (%s)", this, external_name()); 2595 } 2596 2597 it->push(&_annotations); 2598 it->push((Klass**)&_array_klasses); 2599 if (!is_rewritten()) { 2600 it->push(&_constants, MetaspaceClosure::_writable); 2601 } else { 2602 it->push(&_constants); 2603 } 2604 it->push(&_inner_classes); 2605 #if INCLUDE_JVMTI 2606 it->push(&_previous_versions); 2607 #endif 2608 #if INCLUDE_CDS 2609 // For "old" classes with methods containing the jsr bytecode, the _methods array will 2610 // be rewritten during runtime (see Rewriter::rewrite_jsrs()) but they cannot be safely 2611 // checked here with ByteCodeStream. All methods that can't be verified are made writable. 2612 // The length check on the _methods is necessary because classes which don't have any 2613 // methods share the Universe::_the_empty_method_array which is in the RO region. 2614 if (_methods != nullptr && _methods->length() > 0 && !can_be_verified_at_dumptime()) { 2615 // To handle jsr bytecode, new Method* maybe stored into _methods 2616 it->push(&_methods, MetaspaceClosure::_writable); 2617 } else { 2618 #endif 2619 it->push(&_methods); 2620 #if INCLUDE_CDS 2621 } 2622 #endif 2623 it->push(&_default_methods); 2624 it->push(&_local_interfaces); 2625 it->push(&_transitive_interfaces); 2626 it->push(&_method_ordering); 2627 if (!is_rewritten()) { 2628 it->push(&_default_vtable_indices, MetaspaceClosure::_writable); 2629 } else { 2630 it->push(&_default_vtable_indices); 2631 } 2632 2633 it->push(&_fieldinfo_stream); 2634 it->push(&_fieldinfo_search_table); 2635 // _fields_status might be written into by Rewriter::scan_method() -> fd.set_has_initialized_final_update() 2636 it->push(&_fields_status, MetaspaceClosure::_writable); 2637 2638 if (itable_length() > 0) { 2639 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable(); 2640 int method_table_offset_in_words = ioe->offset()/wordSize; 2641 int itable_offset_in_words = (int)(start_of_itable() - (intptr_t*)this); 2642 2643 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words) 2644 / itableOffsetEntry::size(); 2645 2646 for (int i = 0; i < nof_interfaces; i ++, ioe ++) { 2647 if (ioe->interface_klass() != nullptr) { 2648 it->push(ioe->interface_klass_addr()); 2649 itableMethodEntry* ime = ioe->first_method_entry(this); 2650 int n = klassItable::method_count_for_interface(ioe->interface_klass()); 2651 for (int index = 0; index < n; index ++) { 2652 it->push(ime[index].method_addr()); 2653 } 2654 } 2655 } 2656 } 2657 2658 it->push(&_nest_host); 2659 it->push(&_nest_members); 2660 it->push(&_permitted_subclasses); 2661 it->push(&_record_components); 2662 } 2663 2664 #if INCLUDE_CDS 2665 void InstanceKlass::remove_unshareable_info() { 2666 2667 if (is_linked()) { 2668 assert(can_be_verified_at_dumptime(), "must be"); 2669 // Remember this so we can avoid walking the hierarchy at runtime. 2670 set_verified_at_dump_time(); 2671 } 2672 2673 _misc_flags.set_has_init_deps_processed(false); 2674 2675 Klass::remove_unshareable_info(); 2676 2677 if (SystemDictionaryShared::has_class_failed_verification(this)) { 2678 // Classes are attempted to link during dumping and may fail, 2679 // but these classes are still in the dictionary and class list in CLD. 2680 // If the class has failed verification, there is nothing else to remove. 2681 return; 2682 } 2683 2684 // Reset to the 'allocated' state to prevent any premature accessing to 2685 // a shared class at runtime while the class is still being loaded and 2686 // restored. A class' init_state is set to 'loaded' at runtime when it's 2687 // being added to class hierarchy (see InstanceKlass:::add_to_hierarchy()). 2688 _init_state = allocated; 2689 2690 { // Otherwise this needs to take out the Compile_lock. 2691 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint"); 2692 init_implementor(); 2693 } 2694 2695 // Call remove_unshareable_info() on other objects that belong to this class, except 2696 // for constants()->remove_unshareable_info(), which is called in a separate pass in 2697 // ArchiveBuilder::make_klasses_shareable(), 2698 2699 for (int i = 0; i < methods()->length(); i++) { 2700 Method* m = methods()->at(i); 2701 m->remove_unshareable_info(); 2702 } 2703 2704 // do array classes also. 2705 if (array_klasses() != nullptr) { 2706 array_klasses()->remove_unshareable_info(); 2707 } 2708 2709 // These are not allocated from metaspace. They are safe to set to null. 2710 _source_debug_extension = nullptr; 2711 _dep_context = nullptr; 2712 _osr_nmethods_head = nullptr; 2713 #if INCLUDE_JVMTI 2714 _breakpoints = nullptr; 2715 _previous_versions = nullptr; 2716 _cached_class_file = nullptr; 2717 _jvmti_cached_class_field_map = nullptr; 2718 #endif 2719 2720 _init_thread = nullptr; 2721 _methods_jmethod_ids = nullptr; 2722 _jni_ids = nullptr; 2723 _oop_map_cache = nullptr; 2724 if (CDSConfig::is_dumping_method_handles() && HeapShared::is_lambda_proxy_klass(this)) { 2725 // keep _nest_host 2726 } else { 2727 // clear _nest_host to ensure re-load at runtime 2728 _nest_host = nullptr; 2729 } 2730 init_shared_package_entry(); 2731 _dep_context_last_cleaned = 0; 2732 DEBUG_ONLY(_shared_class_load_count = 0); 2733 2734 remove_unshareable_flags(); 2735 2736 DEBUG_ONLY(FieldInfoStream::validate_search_table(_constants, _fieldinfo_stream, _fieldinfo_search_table)); 2737 } 2738 2739 void InstanceKlass::remove_unshareable_flags() { 2740 // clear all the flags/stats that shouldn't be in the archived version 2741 assert(!is_scratch_class(), "must be"); 2742 assert(!has_been_redefined(), "must be"); 2743 #if INCLUDE_JVMTI 2744 set_is_being_redefined(false); 2745 #endif 2746 set_has_resolved_methods(false); 2747 } 2748 2749 void InstanceKlass::remove_java_mirror() { 2750 Klass::remove_java_mirror(); 2751 2752 // do array classes also. 2753 if (array_klasses() != nullptr) { 2754 array_klasses()->remove_java_mirror(); 2755 } 2756 } 2757 2758 void InstanceKlass::init_shared_package_entry() { 2759 assert(CDSConfig::is_dumping_archive(), "must be"); 2760 #if !INCLUDE_CDS_JAVA_HEAP 2761 _package_entry = nullptr; 2762 #else 2763 if (CDSConfig::is_dumping_full_module_graph()) { 2764 if (defined_by_other_loaders()) { 2765 _package_entry = nullptr; 2766 } else { 2767 _package_entry = PackageEntry::get_archived_entry(_package_entry); 2768 } 2769 } else if (CDSConfig::is_dumping_dynamic_archive() && 2770 CDSConfig::is_using_full_module_graph() && 2771 MetaspaceShared::is_in_shared_metaspace(_package_entry)) { 2772 // _package_entry is an archived package in the base archive. Leave it as is. 2773 } else { 2774 _package_entry = nullptr; 2775 } 2776 ArchivePtrMarker::mark_pointer((address**)&_package_entry); 2777 #endif 2778 } 2779 2780 void InstanceKlass::compute_has_loops_flag_for_methods() { 2781 Array<Method*>* methods = this->methods(); 2782 for (int index = 0; index < methods->length(); ++index) { 2783 Method* m = methods->at(index); 2784 if (!m->is_overpass()) { // work around JDK-8305771 2785 m->compute_has_loops_flag(); 2786 } 2787 } 2788 } 2789 2790 void InstanceKlass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain, 2791 PackageEntry* pkg_entry, TRAPS) { 2792 // InstanceKlass::add_to_hierarchy() sets the init_state to loaded 2793 // before the InstanceKlass is added to the SystemDictionary. Make 2794 // sure the current state is <loaded. 2795 assert(!is_loaded(), "invalid init state"); 2796 assert(!shared_loading_failed(), "Must not try to load failed class again"); 2797 set_package(loader_data, pkg_entry, CHECK); 2798 Klass::restore_unshareable_info(loader_data, protection_domain, CHECK); 2799 2800 Array<Method*>* methods = this->methods(); 2801 int num_methods = methods->length(); 2802 for (int index = 0; index < num_methods; ++index) { 2803 methods->at(index)->restore_unshareable_info(CHECK); 2804 } 2805 #if INCLUDE_JVMTI 2806 if (JvmtiExport::has_redefined_a_class()) { 2807 // Reinitialize vtable because RedefineClasses may have changed some 2808 // entries in this vtable for super classes so the CDS vtable might 2809 // point to old or obsolete entries. RedefineClasses doesn't fix up 2810 // vtables in the shared system dictionary, only the main one. 2811 // It also redefines the itable too so fix that too. 2812 // First fix any default methods that point to a super class that may 2813 // have been redefined. 2814 bool trace_name_printed = false; 2815 adjust_default_methods(&trace_name_printed); 2816 if (verified_at_dump_time()) { 2817 // Initialize vtable and itable for classes which can be verified at dump time. 2818 // Unlinked classes such as old classes with major version < 50 cannot be verified 2819 // at dump time. 2820 vtable().initialize_vtable(); 2821 itable().initialize_itable(); 2822 } 2823 } 2824 #endif // INCLUDE_JVMTI 2825 2826 // restore constant pool resolved references 2827 constants()->restore_unshareable_info(CHECK); 2828 2829 if (array_klasses() != nullptr) { 2830 // To get a consistent list of classes we need MultiArray_lock to ensure 2831 // array classes aren't observed while they are being restored. 2832 RecursiveLocker rl(MultiArray_lock, THREAD); 2833 assert(this == array_klasses()->bottom_klass(), "sanity"); 2834 // Array classes have null protection domain. 2835 // --> see ArrayKlass::complete_create_array_klass() 2836 array_klasses()->restore_unshareable_info(class_loader_data(), Handle(), CHECK); 2837 } 2838 2839 // Initialize @ValueBased class annotation if not already set in the archived klass. 2840 if (DiagnoseSyncOnValueBasedClasses && has_value_based_class_annotation() && !is_value_based()) { 2841 set_is_value_based(); 2842 } 2843 2844 DEBUG_ONLY(FieldInfoStream::validate_search_table(_constants, _fieldinfo_stream, _fieldinfo_search_table)); 2845 } 2846 2847 // Check if a class or any of its supertypes has a version older than 50. 2848 // CDS will not perform verification of old classes during dump time because 2849 // without changing the old verifier, the verification constraint cannot be 2850 // retrieved during dump time. 2851 // Verification of archived old classes will be performed during run time. 2852 bool InstanceKlass::can_be_verified_at_dumptime() const { 2853 if (MetaspaceShared::is_in_shared_metaspace(this)) { 2854 // This is a class that was dumped into the base archive, so we know 2855 // it was verified at dump time. 2856 return true; 2857 } 2858 if (major_version() < 50 /*JAVA_6_VERSION*/) { 2859 return false; 2860 } 2861 if (java_super() != nullptr && !java_super()->can_be_verified_at_dumptime()) { 2862 return false; 2863 } 2864 Array<InstanceKlass*>* interfaces = local_interfaces(); 2865 int len = interfaces->length(); 2866 for (int i = 0; i < len; i++) { 2867 if (!interfaces->at(i)->can_be_verified_at_dumptime()) { 2868 return false; 2869 } 2870 } 2871 return true; 2872 } 2873 2874 #endif // INCLUDE_CDS 2875 2876 #if INCLUDE_JVMTI 2877 static void clear_all_breakpoints(Method* m) { 2878 m->clear_all_breakpoints(); 2879 } 2880 #endif 2881 2882 void InstanceKlass::unload_class(InstanceKlass* ik) { 2883 2884 if (ik->is_scratch_class()) { 2885 assert(ik->dependencies().is_empty(), "dependencies should be empty for scratch classes"); 2886 return; 2887 } 2888 assert(ik->is_loaded(), "class should be loaded " PTR_FORMAT, p2i(ik)); 2889 2890 // Release dependencies. 2891 ik->dependencies().remove_all_dependents(); 2892 2893 // notify the debugger 2894 if (JvmtiExport::should_post_class_unload()) { 2895 JvmtiExport::post_class_unload(ik); 2896 } 2897 2898 // notify ClassLoadingService of class unload 2899 ClassLoadingService::notify_class_unloaded(ik); 2900 2901 SystemDictionaryShared::handle_class_unloading(ik); 2902 2903 if (log_is_enabled(Info, class, unload)) { 2904 ResourceMark rm; 2905 log_info(class, unload)("unloading class %s " PTR_FORMAT, ik->external_name(), p2i(ik)); 2906 } 2907 2908 Events::log_class_unloading(Thread::current(), ik); 2909 2910 #if INCLUDE_JFR 2911 assert(ik != nullptr, "invariant"); 2912 EventClassUnload event; 2913 event.set_unloadedClass(ik); 2914 event.set_definingClassLoader(ik->class_loader_data()); 2915 event.commit(); 2916 #endif 2917 } 2918 2919 static void method_release_C_heap_structures(Method* m) { 2920 m->release_C_heap_structures(); 2921 } 2922 2923 // Called also by InstanceKlass::deallocate_contents, with false for release_sub_metadata. 2924 void InstanceKlass::release_C_heap_structures(bool release_sub_metadata) { 2925 // Clean up C heap 2926 Klass::release_C_heap_structures(); 2927 2928 // Deallocate and call destructors for MDO mutexes 2929 if (release_sub_metadata) { 2930 methods_do(method_release_C_heap_structures); 2931 } 2932 2933 // Deallocate oop map cache 2934 if (_oop_map_cache != nullptr) { 2935 delete _oop_map_cache; 2936 _oop_map_cache = nullptr; 2937 } 2938 2939 // Deallocate JNI identifiers for jfieldIDs 2940 JNIid::deallocate(jni_ids()); 2941 set_jni_ids(nullptr); 2942 2943 jmethodID* jmeths = _methods_jmethod_ids; 2944 if (jmeths != nullptr) { 2945 release_set_methods_jmethod_ids(nullptr); 2946 FreeHeap(jmeths); 2947 } 2948 2949 assert(_dep_context == nullptr, 2950 "dependencies should already be cleaned"); 2951 2952 #if INCLUDE_JVMTI 2953 // Deallocate breakpoint records 2954 if (breakpoints() != nullptr) { 2955 methods_do(clear_all_breakpoints); 2956 assert(breakpoints() == nullptr, "should have cleared breakpoints"); 2957 } 2958 2959 // deallocate the cached class file 2960 if (_cached_class_file != nullptr) { 2961 os::free(_cached_class_file); 2962 _cached_class_file = nullptr; 2963 } 2964 #endif 2965 2966 FREE_C_HEAP_ARRAY(char, _source_debug_extension); 2967 2968 if (release_sub_metadata) { 2969 constants()->release_C_heap_structures(); 2970 } 2971 } 2972 2973 // The constant pool is on stack if any of the methods are executing or 2974 // referenced by handles. 2975 bool InstanceKlass::on_stack() const { 2976 return _constants->on_stack(); 2977 } 2978 2979 Symbol* InstanceKlass::source_file_name() const { return _constants->source_file_name(); } 2980 u2 InstanceKlass::source_file_name_index() const { return _constants->source_file_name_index(); } 2981 void InstanceKlass::set_source_file_name_index(u2 sourcefile_index) { _constants->set_source_file_name_index(sourcefile_index); } 2982 2983 // minor and major version numbers of class file 2984 u2 InstanceKlass::minor_version() const { return _constants->minor_version(); } 2985 void InstanceKlass::set_minor_version(u2 minor_version) { _constants->set_minor_version(minor_version); } 2986 u2 InstanceKlass::major_version() const { return _constants->major_version(); } 2987 void InstanceKlass::set_major_version(u2 major_version) { _constants->set_major_version(major_version); } 2988 2989 const InstanceKlass* InstanceKlass::get_klass_version(int version) const { 2990 for (const InstanceKlass* ik = this; ik != nullptr; ik = ik->previous_versions()) { 2991 if (ik->constants()->version() == version) { 2992 return ik; 2993 } 2994 } 2995 return nullptr; 2996 } 2997 2998 void InstanceKlass::set_source_debug_extension(const char* array, int length) { 2999 if (array == nullptr) { 3000 _source_debug_extension = nullptr; 3001 } else { 3002 // Adding one to the attribute length in order to store a null terminator 3003 // character could cause an overflow because the attribute length is 3004 // already coded with an u4 in the classfile, but in practice, it's 3005 // unlikely to happen. 3006 assert((length+1) > length, "Overflow checking"); 3007 char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass); 3008 for (int i = 0; i < length; i++) { 3009 sde[i] = array[i]; 3010 } 3011 sde[length] = '\0'; 3012 _source_debug_extension = sde; 3013 } 3014 } 3015 3016 Symbol* InstanceKlass::generic_signature() const { return _constants->generic_signature(); } 3017 u2 InstanceKlass::generic_signature_index() const { return _constants->generic_signature_index(); } 3018 void InstanceKlass::set_generic_signature_index(u2 sig_index) { _constants->set_generic_signature_index(sig_index); } 3019 3020 const char* InstanceKlass::signature_name() const { 3021 3022 // Get the internal name as a c string 3023 const char* src = (const char*) (name()->as_C_string()); 3024 const int src_length = (int)strlen(src); 3025 3026 char* dest = NEW_RESOURCE_ARRAY(char, src_length + 3); 3027 3028 // Add L as type indicator 3029 int dest_index = 0; 3030 dest[dest_index++] = JVM_SIGNATURE_CLASS; 3031 3032 // Add the actual class name 3033 for (int src_index = 0; src_index < src_length; ) { 3034 dest[dest_index++] = src[src_index++]; 3035 } 3036 3037 if (is_hidden()) { // Replace the last '+' with a '.'. 3038 for (int index = (int)src_length; index > 0; index--) { 3039 if (dest[index] == '+') { 3040 dest[index] = JVM_SIGNATURE_DOT; 3041 break; 3042 } 3043 } 3044 } 3045 3046 // Add the semicolon and the null 3047 dest[dest_index++] = JVM_SIGNATURE_ENDCLASS; 3048 dest[dest_index] = '\0'; 3049 return dest; 3050 } 3051 3052 ModuleEntry* InstanceKlass::module() const { 3053 if (is_hidden() && 3054 in_unnamed_package() && 3055 class_loader_data()->has_class_mirror_holder()) { 3056 // For a non-strong hidden class defined to an unnamed package, 3057 // its (class held) CLD will not have an unnamed module created for it. 3058 // Two choices to find the correct ModuleEntry: 3059 // 1. If hidden class is within a nest, use nest host's module 3060 // 2. Find the unnamed module off from the class loader 3061 // For now option #2 is used since a nest host is not set until 3062 // after the instance class is created in jvm_lookup_define_class(). 3063 if (class_loader_data()->is_boot_class_loader_data()) { 3064 return ClassLoaderData::the_null_class_loader_data()->unnamed_module(); 3065 } else { 3066 oop module = java_lang_ClassLoader::unnamedModule(class_loader_data()->class_loader()); 3067 assert(java_lang_Module::is_instance(module), "Not an instance of java.lang.Module"); 3068 return java_lang_Module::module_entry(module); 3069 } 3070 } 3071 3072 // Class is in a named package 3073 if (!in_unnamed_package()) { 3074 return _package_entry->module(); 3075 } 3076 3077 // Class is in an unnamed package, return its loader's unnamed module 3078 return class_loader_data()->unnamed_module(); 3079 } 3080 3081 bool InstanceKlass::in_javabase_module() const { 3082 return module()->name() == vmSymbols::java_base(); 3083 } 3084 3085 void InstanceKlass::set_package(ClassLoaderData* loader_data, PackageEntry* pkg_entry, TRAPS) { 3086 3087 // ensure java/ packages only loaded by boot or platform builtin loaders 3088 // not needed for shared class since CDS does not archive prohibited classes. 3089 if (!is_shared()) { 3090 check_prohibited_package(name(), loader_data, CHECK); 3091 } 3092 3093 if (is_shared() && _package_entry != nullptr) { 3094 if (CDSConfig::is_using_full_module_graph() && _package_entry == pkg_entry) { 3095 // we can use the saved package 3096 assert(MetaspaceShared::is_in_shared_metaspace(_package_entry), "must be"); 3097 return; 3098 } else { 3099 _package_entry = nullptr; 3100 } 3101 } 3102 3103 // ClassLoader::package_from_class_name has already incremented the refcount of the symbol 3104 // it returns, so we need to decrement it when the current function exits. 3105 TempNewSymbol from_class_name = 3106 (pkg_entry != nullptr) ? nullptr : ClassLoader::package_from_class_name(name()); 3107 3108 Symbol* pkg_name; 3109 if (pkg_entry != nullptr) { 3110 pkg_name = pkg_entry->name(); 3111 } else { 3112 pkg_name = from_class_name; 3113 } 3114 3115 if (pkg_name != nullptr && loader_data != nullptr) { 3116 3117 // Find in class loader's package entry table. 3118 _package_entry = pkg_entry != nullptr ? pkg_entry : loader_data->packages()->lookup_only(pkg_name); 3119 3120 // If the package name is not found in the loader's package 3121 // entry table, it is an indication that the package has not 3122 // been defined. Consider it defined within the unnamed module. 3123 if (_package_entry == nullptr) { 3124 3125 if (!ModuleEntryTable::javabase_defined()) { 3126 // Before java.base is defined during bootstrapping, define all packages in 3127 // the java.base module. If a non-java.base package is erroneously placed 3128 // in the java.base module it will be caught later when java.base 3129 // is defined by ModuleEntryTable::verify_javabase_packages check. 3130 assert(ModuleEntryTable::javabase_moduleEntry() != nullptr, JAVA_BASE_NAME " module is null"); 3131 _package_entry = loader_data->packages()->create_entry_if_absent(pkg_name, ModuleEntryTable::javabase_moduleEntry()); 3132 } else { 3133 assert(loader_data->unnamed_module() != nullptr, "unnamed module is null"); 3134 _package_entry = loader_data->packages()->create_entry_if_absent(pkg_name, loader_data->unnamed_module()); 3135 } 3136 3137 // A package should have been successfully created 3138 DEBUG_ONLY(ResourceMark rm(THREAD)); 3139 assert(_package_entry != nullptr, "Package entry for class %s not found, loader %s", 3140 name()->as_C_string(), loader_data->loader_name_and_id()); 3141 } 3142 3143 if (log_is_enabled(Debug, module)) { 3144 ResourceMark rm(THREAD); 3145 ModuleEntry* m = _package_entry->module(); 3146 log_trace(module)("Setting package: class: %s, package: %s, loader: %s, module: %s", 3147 external_name(), 3148 pkg_name->as_C_string(), 3149 loader_data->loader_name_and_id(), 3150 (m->is_named() ? m->name()->as_C_string() : UNNAMED_MODULE)); 3151 } 3152 } else { 3153 ResourceMark rm(THREAD); 3154 log_trace(module)("Setting package: class: %s, package: unnamed, loader: %s, module: %s", 3155 external_name(), 3156 (loader_data != nullptr) ? loader_data->loader_name_and_id() : "null", 3157 UNNAMED_MODULE); 3158 } 3159 } 3160 3161 // Function set_classpath_index ensures that for a non-null _package_entry 3162 // of the InstanceKlass, the entry is in the boot loader's package entry table. 3163 // It then sets the classpath_index in the package entry record. 3164 // 3165 // The classpath_index field is used to find the entry on the boot loader class 3166 // path for packages with classes loaded by the boot loader from -Xbootclasspath/a 3167 // in an unnamed module. It is also used to indicate (for all packages whose 3168 // classes are loaded by the boot loader) that at least one of the package's 3169 // classes has been loaded. 3170 void InstanceKlass::set_classpath_index(s2 path_index) { 3171 if (_package_entry != nullptr) { 3172 DEBUG_ONLY(PackageEntryTable* pkg_entry_tbl = ClassLoaderData::the_null_class_loader_data()->packages();) 3173 assert(pkg_entry_tbl->lookup_only(_package_entry->name()) == _package_entry, "Should be same"); 3174 assert(path_index != -1, "Unexpected classpath_index"); 3175 _package_entry->set_classpath_index(path_index); 3176 } 3177 } 3178 3179 // different versions of is_same_class_package 3180 3181 bool InstanceKlass::is_same_class_package(const Klass* class2) const { 3182 oop classloader1 = this->class_loader(); 3183 PackageEntry* classpkg1 = this->package(); 3184 if (class2->is_objArray_klass()) { 3185 class2 = ObjArrayKlass::cast(class2)->bottom_klass(); 3186 } 3187 3188 oop classloader2; 3189 PackageEntry* classpkg2; 3190 if (class2->is_instance_klass()) { 3191 classloader2 = class2->class_loader(); 3192 classpkg2 = class2->package(); 3193 } else { 3194 assert(class2->is_typeArray_klass(), "should be type array"); 3195 classloader2 = nullptr; 3196 classpkg2 = nullptr; 3197 } 3198 3199 // Same package is determined by comparing class loader 3200 // and package entries. Both must be the same. This rule 3201 // applies even to classes that are defined in the unnamed 3202 // package, they still must have the same class loader. 3203 if ((classloader1 == classloader2) && (classpkg1 == classpkg2)) { 3204 return true; 3205 } 3206 3207 return false; 3208 } 3209 3210 // return true if this class and other_class are in the same package. Classloader 3211 // and classname information is enough to determine a class's package 3212 bool InstanceKlass::is_same_class_package(oop other_class_loader, 3213 const Symbol* other_class_name) const { 3214 if (class_loader() != other_class_loader) { 3215 return false; 3216 } 3217 if (name()->fast_compare(other_class_name) == 0) { 3218 return true; 3219 } 3220 3221 { 3222 ResourceMark rm; 3223 3224 bool bad_class_name = false; 3225 TempNewSymbol other_pkg = ClassLoader::package_from_class_name(other_class_name, &bad_class_name); 3226 if (bad_class_name) { 3227 return false; 3228 } 3229 // Check that package_from_class_name() returns null, not "", if there is no package. 3230 assert(other_pkg == nullptr || other_pkg->utf8_length() > 0, "package name is empty string"); 3231 3232 const Symbol* const this_package_name = 3233 this->package() != nullptr ? this->package()->name() : nullptr; 3234 3235 if (this_package_name == nullptr || other_pkg == nullptr) { 3236 // One of the two doesn't have a package. Only return true if the other 3237 // one also doesn't have a package. 3238 return this_package_name == other_pkg; 3239 } 3240 3241 // Check if package is identical 3242 return this_package_name->fast_compare(other_pkg) == 0; 3243 } 3244 } 3245 3246 static bool is_prohibited_package_slow(Symbol* class_name) { 3247 // Caller has ResourceMark 3248 int length; 3249 jchar* unicode = class_name->as_unicode(length); 3250 return (length >= 5 && 3251 unicode[0] == 'j' && 3252 unicode[1] == 'a' && 3253 unicode[2] == 'v' && 3254 unicode[3] == 'a' && 3255 unicode[4] == '/'); 3256 } 3257 3258 // Only boot and platform class loaders can define classes in "java/" packages. 3259 void InstanceKlass::check_prohibited_package(Symbol* class_name, 3260 ClassLoaderData* loader_data, 3261 TRAPS) { 3262 if (!loader_data->is_boot_class_loader_data() && 3263 !loader_data->is_platform_class_loader_data() && 3264 class_name != nullptr && class_name->utf8_length() >= 5) { 3265 ResourceMark rm(THREAD); 3266 bool prohibited; 3267 const u1* base = class_name->base(); 3268 if ((base[0] | base[1] | base[2] | base[3] | base[4]) & 0x80) { 3269 prohibited = is_prohibited_package_slow(class_name); 3270 } else { 3271 char* name = class_name->as_C_string(); 3272 prohibited = (strncmp(name, JAVAPKG, JAVAPKG_LEN) == 0 && name[JAVAPKG_LEN] == '/'); 3273 } 3274 if (prohibited) { 3275 TempNewSymbol pkg_name = ClassLoader::package_from_class_name(class_name); 3276 assert(pkg_name != nullptr, "Error in parsing package name starting with 'java/'"); 3277 char* name = pkg_name->as_C_string(); 3278 const char* class_loader_name = loader_data->loader_name_and_id(); 3279 StringUtils::replace_no_expand(name, "/", "."); 3280 const char* msg_text1 = "Class loader (instance of): "; 3281 const char* msg_text2 = " tried to load prohibited package name: "; 3282 size_t len = strlen(msg_text1) + strlen(class_loader_name) + strlen(msg_text2) + strlen(name) + 1; 3283 char* message = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, len); 3284 jio_snprintf(message, len, "%s%s%s%s", msg_text1, class_loader_name, msg_text2, name); 3285 THROW_MSG(vmSymbols::java_lang_SecurityException(), message); 3286 } 3287 } 3288 return; 3289 } 3290 3291 bool InstanceKlass::find_inner_classes_attr(int* ooff, int* noff, TRAPS) const { 3292 constantPoolHandle i_cp(THREAD, constants()); 3293 for (InnerClassesIterator iter(this); !iter.done(); iter.next()) { 3294 int ioff = iter.inner_class_info_index(); 3295 if (ioff != 0) { 3296 // Check to see if the name matches the class we're looking for 3297 // before attempting to find the class. 3298 if (i_cp->klass_name_at_matches(this, ioff)) { 3299 Klass* inner_klass = i_cp->klass_at(ioff, CHECK_false); 3300 if (this == inner_klass) { 3301 *ooff = iter.outer_class_info_index(); 3302 *noff = iter.inner_name_index(); 3303 return true; 3304 } 3305 } 3306 } 3307 } 3308 return false; 3309 } 3310 3311 InstanceKlass* InstanceKlass::compute_enclosing_class(bool* inner_is_member, TRAPS) const { 3312 InstanceKlass* outer_klass = nullptr; 3313 *inner_is_member = false; 3314 int ooff = 0, noff = 0; 3315 bool has_inner_classes_attr = find_inner_classes_attr(&ooff, &noff, THREAD); 3316 if (has_inner_classes_attr) { 3317 constantPoolHandle i_cp(THREAD, constants()); 3318 if (ooff != 0) { 3319 Klass* ok = i_cp->klass_at(ooff, CHECK_NULL); 3320 if (!ok->is_instance_klass()) { 3321 // If the outer class is not an instance klass then it cannot have 3322 // declared any inner classes. 3323 ResourceMark rm(THREAD); 3324 // Names are all known to be < 64k so we know this formatted message is not excessively large. 3325 Exceptions::fthrow( 3326 THREAD_AND_LOCATION, 3327 vmSymbols::java_lang_IncompatibleClassChangeError(), 3328 "%s and %s disagree on InnerClasses attribute", 3329 ok->external_name(), 3330 external_name()); 3331 return nullptr; 3332 } 3333 outer_klass = InstanceKlass::cast(ok); 3334 *inner_is_member = true; 3335 } 3336 if (nullptr == outer_klass) { 3337 // It may be a local class; try for that. 3338 int encl_method_class_idx = enclosing_method_class_index(); 3339 if (encl_method_class_idx != 0) { 3340 Klass* ok = i_cp->klass_at(encl_method_class_idx, CHECK_NULL); 3341 outer_klass = InstanceKlass::cast(ok); 3342 *inner_is_member = false; 3343 } 3344 } 3345 } 3346 3347 // If no inner class attribute found for this class. 3348 if (nullptr == outer_klass) return nullptr; 3349 3350 // Throws an exception if outer klass has not declared k as an inner klass 3351 // We need evidence that each klass knows about the other, or else 3352 // the system could allow a spoof of an inner class to gain access rights. 3353 Reflection::check_for_inner_class(outer_klass, this, *inner_is_member, CHECK_NULL); 3354 return outer_klass; 3355 } 3356 3357 u2 InstanceKlass::compute_modifier_flags() const { 3358 u2 access = access_flags().as_unsigned_short(); 3359 3360 // But check if it happens to be member class. 3361 InnerClassesIterator iter(this); 3362 for (; !iter.done(); iter.next()) { 3363 int ioff = iter.inner_class_info_index(); 3364 // Inner class attribute can be zero, skip it. 3365 // Strange but true: JVM spec. allows null inner class refs. 3366 if (ioff == 0) continue; 3367 3368 // only look at classes that are already loaded 3369 // since we are looking for the flags for our self. 3370 Symbol* inner_name = constants()->klass_name_at(ioff); 3371 if (name() == inner_name) { 3372 // This is really a member class. 3373 access = iter.inner_access_flags(); 3374 break; 3375 } 3376 } 3377 // Remember to strip ACC_SUPER bit 3378 return (access & (~JVM_ACC_SUPER)); 3379 } 3380 3381 jint InstanceKlass::jvmti_class_status() const { 3382 jint result = 0; 3383 3384 if (is_linked()) { 3385 result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED; 3386 } 3387 3388 if (is_initialized()) { 3389 assert(is_linked(), "Class status is not consistent"); 3390 result |= JVMTI_CLASS_STATUS_INITIALIZED; 3391 } 3392 if (is_in_error_state()) { 3393 result |= JVMTI_CLASS_STATUS_ERROR; 3394 } 3395 return result; 3396 } 3397 3398 Method* InstanceKlass::method_at_itable(InstanceKlass* holder, int index, TRAPS) { 3399 bool implements_interface; // initialized by method_at_itable_or_null 3400 Method* m = method_at_itable_or_null(holder, index, 3401 implements_interface); // out parameter 3402 if (m != nullptr) { 3403 assert(implements_interface, "sanity"); 3404 return m; 3405 } else if (implements_interface) { 3406 // Throw AbstractMethodError since corresponding itable slot is empty. 3407 THROW_NULL(vmSymbols::java_lang_AbstractMethodError()); 3408 } else { 3409 // If the interface isn't implemented by the receiver class, 3410 // the VM should throw IncompatibleClassChangeError. 3411 ResourceMark rm(THREAD); 3412 stringStream ss; 3413 bool same_module = (module() == holder->module()); 3414 ss.print("Receiver class %s does not implement " 3415 "the interface %s defining the method to be called " 3416 "(%s%s%s)", 3417 external_name(), holder->external_name(), 3418 (same_module) ? joint_in_module_of_loader(holder) : class_in_module_of_loader(), 3419 (same_module) ? "" : "; ", 3420 (same_module) ? "" : holder->class_in_module_of_loader()); 3421 THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), ss.as_string()); 3422 } 3423 } 3424 3425 Method* InstanceKlass::method_at_itable_or_null(InstanceKlass* holder, int index, bool& implements_interface) { 3426 klassItable itable(this); 3427 for (int i = 0; i < itable.size_offset_table(); i++) { 3428 itableOffsetEntry* offset_entry = itable.offset_entry(i); 3429 if (offset_entry->interface_klass() == holder) { 3430 implements_interface = true; 3431 itableMethodEntry* ime = offset_entry->first_method_entry(this); 3432 Method* m = ime[index].method(); 3433 return m; 3434 } 3435 } 3436 implements_interface = false; 3437 return nullptr; // offset entry not found 3438 } 3439 3440 int InstanceKlass::vtable_index_of_interface_method(Method* intf_method) { 3441 assert(is_linked(), "required"); 3442 assert(intf_method->method_holder()->is_interface(), "not an interface method"); 3443 assert(is_subtype_of(intf_method->method_holder()), "interface not implemented"); 3444 3445 int vtable_index = Method::invalid_vtable_index; 3446 Symbol* name = intf_method->name(); 3447 Symbol* signature = intf_method->signature(); 3448 3449 // First check in default method array 3450 if (!intf_method->is_abstract() && default_methods() != nullptr) { 3451 int index = find_method_index(default_methods(), 3452 name, signature, 3453 Klass::OverpassLookupMode::find, 3454 Klass::StaticLookupMode::find, 3455 Klass::PrivateLookupMode::find); 3456 if (index >= 0) { 3457 vtable_index = default_vtable_indices()->at(index); 3458 } 3459 } 3460 if (vtable_index == Method::invalid_vtable_index) { 3461 // get vtable_index for miranda methods 3462 klassVtable vt = vtable(); 3463 vtable_index = vt.index_of_miranda(name, signature); 3464 } 3465 return vtable_index; 3466 } 3467 3468 #if INCLUDE_JVMTI 3469 // update default_methods for redefineclasses for methods that are 3470 // not yet in the vtable due to concurrent subclass define and superinterface 3471 // redefinition 3472 // Note: those in the vtable, should have been updated via adjust_method_entries 3473 void InstanceKlass::adjust_default_methods(bool* trace_name_printed) { 3474 // search the default_methods for uses of either obsolete or EMCP methods 3475 if (default_methods() != nullptr) { 3476 for (int index = 0; index < default_methods()->length(); index ++) { 3477 Method* old_method = default_methods()->at(index); 3478 if (old_method == nullptr || !old_method->is_old()) { 3479 continue; // skip uninteresting entries 3480 } 3481 assert(!old_method->is_deleted(), "default methods may not be deleted"); 3482 Method* new_method = old_method->get_new_method(); 3483 default_methods()->at_put(index, new_method); 3484 3485 if (log_is_enabled(Info, redefine, class, update)) { 3486 ResourceMark rm; 3487 if (!(*trace_name_printed)) { 3488 log_info(redefine, class, update) 3489 ("adjust: klassname=%s default methods from name=%s", 3490 external_name(), old_method->method_holder()->external_name()); 3491 *trace_name_printed = true; 3492 } 3493 log_debug(redefine, class, update, vtables) 3494 ("default method update: %s(%s) ", 3495 new_method->name()->as_C_string(), new_method->signature()->as_C_string()); 3496 } 3497 } 3498 } 3499 } 3500 #endif // INCLUDE_JVMTI 3501 3502 // On-stack replacement stuff 3503 void InstanceKlass::add_osr_nmethod(nmethod* n) { 3504 assert_lock_strong(NMethodState_lock); 3505 #ifndef PRODUCT 3506 nmethod* prev = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), n->comp_level(), true); 3507 assert(prev == nullptr || !prev->is_in_use() COMPILER2_PRESENT(|| StressRecompilation), 3508 "redundant OSR recompilation detected. memory leak in CodeCache!"); 3509 #endif 3510 // only one compilation can be active 3511 assert(n->is_osr_method(), "wrong kind of nmethod"); 3512 n->set_osr_link(osr_nmethods_head()); 3513 set_osr_nmethods_head(n); 3514 // Raise the highest osr level if necessary 3515 n->method()->set_highest_osr_comp_level(MAX2(n->method()->highest_osr_comp_level(), n->comp_level())); 3516 3517 // Get rid of the osr methods for the same bci that have lower levels. 3518 for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) { 3519 nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true); 3520 if (inv != nullptr && inv->is_in_use()) { 3521 inv->make_not_entrant(nmethod::InvalidationReason::OSR_INVALIDATION_OF_LOWER_LEVEL); 3522 } 3523 } 3524 } 3525 3526 // Remove osr nmethod from the list. Return true if found and removed. 3527 bool InstanceKlass::remove_osr_nmethod(nmethod* n) { 3528 // This is a short non-blocking critical region, so the no safepoint check is ok. 3529 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag); 3530 assert(n->is_osr_method(), "wrong kind of nmethod"); 3531 nmethod* last = nullptr; 3532 nmethod* cur = osr_nmethods_head(); 3533 int max_level = CompLevel_none; // Find the max comp level excluding n 3534 Method* m = n->method(); 3535 // Search for match 3536 bool found = false; 3537 while(cur != nullptr && cur != n) { 3538 if (m == cur->method()) { 3539 // Find max level before n 3540 max_level = MAX2(max_level, cur->comp_level()); 3541 } 3542 last = cur; 3543 cur = cur->osr_link(); 3544 } 3545 nmethod* next = nullptr; 3546 if (cur == n) { 3547 found = true; 3548 next = cur->osr_link(); 3549 if (last == nullptr) { 3550 // Remove first element 3551 set_osr_nmethods_head(next); 3552 } else { 3553 last->set_osr_link(next); 3554 } 3555 } 3556 n->set_osr_link(nullptr); 3557 cur = next; 3558 while (cur != nullptr) { 3559 // Find max level after n 3560 if (m == cur->method()) { 3561 max_level = MAX2(max_level, cur->comp_level()); 3562 } 3563 cur = cur->osr_link(); 3564 } 3565 m->set_highest_osr_comp_level(max_level); 3566 return found; 3567 } 3568 3569 int InstanceKlass::mark_osr_nmethods(DeoptimizationScope* deopt_scope, const Method* m) { 3570 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag); 3571 nmethod* osr = osr_nmethods_head(); 3572 int found = 0; 3573 while (osr != nullptr) { 3574 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain"); 3575 if (osr->method() == m) { 3576 deopt_scope->mark(osr); 3577 found++; 3578 } 3579 osr = osr->osr_link(); 3580 } 3581 return found; 3582 } 3583 3584 nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const { 3585 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag); 3586 nmethod* osr = osr_nmethods_head(); 3587 nmethod* best = nullptr; 3588 while (osr != nullptr) { 3589 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain"); 3590 // There can be a time when a c1 osr method exists but we are waiting 3591 // for a c2 version. When c2 completes its osr nmethod we will trash 3592 // the c1 version and only be able to find the c2 version. However 3593 // while we overflow in the c1 code at back branches we don't want to 3594 // try and switch to the same code as we are already running 3595 3596 if (osr->method() == m && 3597 (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) { 3598 if (match_level) { 3599 if (osr->comp_level() == comp_level) { 3600 // Found a match - return it. 3601 return osr; 3602 } 3603 } else { 3604 if (best == nullptr || (osr->comp_level() > best->comp_level())) { 3605 if (osr->comp_level() == CompilationPolicy::highest_compile_level()) { 3606 // Found the best possible - return it. 3607 return osr; 3608 } 3609 best = osr; 3610 } 3611 } 3612 } 3613 osr = osr->osr_link(); 3614 } 3615 3616 assert(match_level == false || best == nullptr, "shouldn't pick up anything if match_level is set"); 3617 if (best != nullptr && best->comp_level() >= comp_level) { 3618 return best; 3619 } 3620 return nullptr; 3621 } 3622 3623 // ----------------------------------------------------------------------------------------------------- 3624 // Printing 3625 3626 #define BULLET " - " 3627 3628 static const char* state_names[] = { 3629 "allocated", "loaded", "linked", "being_initialized", "fully_initialized", "initialization_error" 3630 }; 3631 3632 static void print_vtable(intptr_t* start, int len, outputStream* st) { 3633 for (int i = 0; i < len; i++) { 3634 intptr_t e = start[i]; 3635 st->print("%d : " INTPTR_FORMAT, i, e); 3636 if (MetaspaceObj::is_valid((Metadata*)e)) { 3637 st->print(" "); 3638 ((Metadata*)e)->print_value_on(st); 3639 } 3640 st->cr(); 3641 } 3642 } 3643 3644 static void print_vtable(vtableEntry* start, int len, outputStream* st) { 3645 return print_vtable(reinterpret_cast<intptr_t*>(start), len, st); 3646 } 3647 3648 const char* InstanceKlass::init_state_name() const { 3649 return state_names[init_state()]; 3650 } 3651 3652 void InstanceKlass::print_on(outputStream* st) const { 3653 assert(is_klass(), "must be klass"); 3654 Klass::print_on(st); 3655 3656 st->print(BULLET"instance size: %d", size_helper()); st->cr(); 3657 st->print(BULLET"klass size: %d", size()); st->cr(); 3658 st->print(BULLET"access: "); access_flags().print_on(st); st->cr(); 3659 st->print(BULLET"flags: "); _misc_flags.print_on(st); st->cr(); 3660 st->print(BULLET"state: "); st->print_cr("%s", init_state_name()); 3661 st->print(BULLET"name: "); name()->print_value_on(st); st->cr(); 3662 st->print(BULLET"super: "); Metadata::print_value_on_maybe_null(st, super()); st->cr(); 3663 st->print(BULLET"sub: "); 3664 Klass* sub = subklass(); 3665 int n; 3666 for (n = 0; sub != nullptr; n++, sub = sub->next_sibling()) { 3667 if (n < MaxSubklassPrintSize) { 3668 sub->print_value_on(st); 3669 st->print(" "); 3670 } 3671 } 3672 if (n >= MaxSubklassPrintSize) st->print("(%zd more klasses...)", n - MaxSubklassPrintSize); 3673 st->cr(); 3674 3675 if (is_interface()) { 3676 st->print_cr(BULLET"nof implementors: %d", nof_implementors()); 3677 if (nof_implementors() == 1) { 3678 st->print_cr(BULLET"implementor: "); 3679 st->print(" "); 3680 implementor()->print_value_on(st); 3681 st->cr(); 3682 } 3683 } 3684 3685 st->print(BULLET"arrays: "); Metadata::print_value_on_maybe_null(st, array_klasses()); st->cr(); 3686 st->print(BULLET"methods: "); methods()->print_value_on(st); st->cr(); 3687 if (Verbose || WizardMode) { 3688 Array<Method*>* method_array = methods(); 3689 for (int i = 0; i < method_array->length(); i++) { 3690 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr(); 3691 } 3692 } 3693 st->print(BULLET"method ordering: "); method_ordering()->print_value_on(st); st->cr(); 3694 if (default_methods() != nullptr) { 3695 st->print(BULLET"default_methods: "); default_methods()->print_value_on(st); st->cr(); 3696 if (Verbose) { 3697 Array<Method*>* method_array = default_methods(); 3698 for (int i = 0; i < method_array->length(); i++) { 3699 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr(); 3700 } 3701 } 3702 } 3703 print_on_maybe_null(st, BULLET"default vtable indices: ", default_vtable_indices()); 3704 st->print(BULLET"local interfaces: "); local_interfaces()->print_value_on(st); st->cr(); 3705 st->print(BULLET"trans. interfaces: "); transitive_interfaces()->print_value_on(st); st->cr(); 3706 3707 st->print(BULLET"secondary supers: "); secondary_supers()->print_value_on(st); st->cr(); 3708 3709 st->print(BULLET"hash_slot: %d", hash_slot()); st->cr(); 3710 st->print(BULLET"secondary bitmap: " UINTX_FORMAT_X_0, _secondary_supers_bitmap); st->cr(); 3711 3712 if (secondary_supers() != nullptr) { 3713 if (Verbose) { 3714 bool is_hashed = (_secondary_supers_bitmap != SECONDARY_SUPERS_BITMAP_FULL); 3715 st->print_cr(BULLET"---- secondary supers (%d words):", _secondary_supers->length()); 3716 for (int i = 0; i < _secondary_supers->length(); i++) { 3717 ResourceMark rm; // for external_name() 3718 Klass* secondary_super = _secondary_supers->at(i); 3719 st->print(BULLET"%2d:", i); 3720 if (is_hashed) { 3721 int home_slot = compute_home_slot(secondary_super, _secondary_supers_bitmap); 3722 int distance = (i - home_slot) & SECONDARY_SUPERS_TABLE_MASK; 3723 st->print(" dist:%02d:", distance); 3724 } 3725 st->print_cr(" %p %s", secondary_super, secondary_super->external_name()); 3726 } 3727 } 3728 } 3729 st->print(BULLET"constants: "); constants()->print_value_on(st); st->cr(); 3730 3731 print_on_maybe_null(st, BULLET"class loader data: ", class_loader_data()); 3732 print_on_maybe_null(st, BULLET"source file: ", source_file_name()); 3733 if (source_debug_extension() != nullptr) { 3734 st->print(BULLET"source debug extension: "); 3735 st->print("%s", source_debug_extension()); 3736 st->cr(); 3737 } 3738 print_on_maybe_null(st, BULLET"class annotations: ", class_annotations()); 3739 print_on_maybe_null(st, BULLET"class type annotations: ", class_type_annotations()); 3740 print_on_maybe_null(st, BULLET"field annotations: ", fields_annotations()); 3741 print_on_maybe_null(st, BULLET"field type annotations: ", fields_type_annotations()); 3742 { 3743 bool have_pv = false; 3744 // previous versions are linked together through the InstanceKlass 3745 for (InstanceKlass* pv_node = previous_versions(); 3746 pv_node != nullptr; 3747 pv_node = pv_node->previous_versions()) { 3748 if (!have_pv) 3749 st->print(BULLET"previous version: "); 3750 have_pv = true; 3751 pv_node->constants()->print_value_on(st); 3752 } 3753 if (have_pv) st->cr(); 3754 } 3755 3756 print_on_maybe_null(st, BULLET"generic signature: ", generic_signature()); 3757 st->print(BULLET"inner classes: "); inner_classes()->print_value_on(st); st->cr(); 3758 st->print(BULLET"nest members: "); nest_members()->print_value_on(st); st->cr(); 3759 print_on_maybe_null(st, BULLET"record components: ", record_components()); 3760 st->print(BULLET"permitted subclasses: "); permitted_subclasses()->print_value_on(st); st->cr(); 3761 if (java_mirror() != nullptr) { 3762 st->print(BULLET"java mirror: "); 3763 java_mirror()->print_value_on(st); 3764 st->cr(); 3765 } else { 3766 st->print_cr(BULLET"java mirror: null"); 3767 } 3768 st->print(BULLET"vtable length %d (start addr: " PTR_FORMAT ")", vtable_length(), p2i(start_of_vtable())); st->cr(); 3769 if (vtable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_vtable(), vtable_length(), st); 3770 st->print(BULLET"itable length %d (start addr: " PTR_FORMAT ")", itable_length(), p2i(start_of_itable())); st->cr(); 3771 if (itable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_itable(), itable_length(), st); 3772 st->print_cr(BULLET"---- static fields (%d words):", static_field_size()); 3773 3774 FieldPrinter print_static_field(st); 3775 ((InstanceKlass*)this)->do_local_static_fields(&print_static_field); 3776 st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size()); 3777 FieldPrinter print_nonstatic_field(st); 3778 InstanceKlass* ik = const_cast<InstanceKlass*>(this); 3779 ik->print_nonstatic_fields(&print_nonstatic_field); 3780 3781 st->print(BULLET"non-static oop maps (%d entries): ", nonstatic_oop_map_count()); 3782 OopMapBlock* map = start_of_nonstatic_oop_maps(); 3783 OopMapBlock* end_map = map + nonstatic_oop_map_count(); 3784 while (map < end_map) { 3785 st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1)); 3786 map++; 3787 } 3788 st->cr(); 3789 3790 if (fieldinfo_search_table() != nullptr) { 3791 st->print_cr(BULLET"---- field info search table:"); 3792 FieldInfoStream::print_search_table(st, _constants, _fieldinfo_stream, _fieldinfo_search_table); 3793 } 3794 } 3795 3796 void InstanceKlass::print_value_on(outputStream* st) const { 3797 assert(is_klass(), "must be klass"); 3798 if (Verbose || WizardMode) access_flags().print_on(st); 3799 name()->print_value_on(st); 3800 } 3801 3802 void FieldPrinter::do_field(fieldDescriptor* fd) { 3803 _st->print(BULLET); 3804 if (_obj == nullptr) { 3805 fd->print_on(_st); 3806 _st->cr(); 3807 } else { 3808 fd->print_on_for(_st, _obj); 3809 _st->cr(); 3810 } 3811 } 3812 3813 3814 void InstanceKlass::oop_print_on(oop obj, outputStream* st) { 3815 Klass::oop_print_on(obj, st); 3816 3817 if (this == vmClasses::String_klass()) { 3818 typeArrayOop value = java_lang_String::value(obj); 3819 juint length = java_lang_String::length(obj); 3820 if (value != nullptr && 3821 value->is_typeArray() && 3822 length <= (juint) value->length()) { 3823 st->print(BULLET"string: "); 3824 java_lang_String::print(obj, st); 3825 st->cr(); 3826 } 3827 } 3828 3829 st->print_cr(BULLET"---- fields (total size %zu words):", oop_size(obj)); 3830 FieldPrinter print_field(st, obj); 3831 print_nonstatic_fields(&print_field); 3832 3833 if (this == vmClasses::Class_klass()) { 3834 st->print(BULLET"signature: "); 3835 java_lang_Class::print_signature(obj, st); 3836 st->cr(); 3837 Klass* real_klass = java_lang_Class::as_Klass(obj); 3838 if (real_klass != nullptr && real_klass->is_instance_klass()) { 3839 st->print_cr(BULLET"---- static fields (%d):", java_lang_Class::static_oop_field_count(obj)); 3840 InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field); 3841 } 3842 } else if (this == vmClasses::MethodType_klass()) { 3843 st->print(BULLET"signature: "); 3844 java_lang_invoke_MethodType::print_signature(obj, st); 3845 st->cr(); 3846 } 3847 } 3848 3849 #ifndef PRODUCT 3850 3851 bool InstanceKlass::verify_itable_index(int i) { 3852 int method_count = klassItable::method_count_for_interface(this); 3853 assert(i >= 0 && i < method_count, "index out of bounds"); 3854 return true; 3855 } 3856 3857 #endif //PRODUCT 3858 3859 void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) { 3860 st->print("a "); 3861 name()->print_value_on(st); 3862 obj->print_address_on(st); 3863 if (this == vmClasses::String_klass() 3864 && java_lang_String::value(obj) != nullptr) { 3865 ResourceMark rm; 3866 int len = java_lang_String::length(obj); 3867 int plen = (len < 24 ? len : 12); 3868 char* str = java_lang_String::as_utf8_string(obj, 0, plen); 3869 st->print(" = \"%s\"", str); 3870 if (len > plen) 3871 st->print("...[%d]", len); 3872 } else if (this == vmClasses::Class_klass()) { 3873 Klass* k = java_lang_Class::as_Klass(obj); 3874 st->print(" = "); 3875 if (k != nullptr) { 3876 k->print_value_on(st); 3877 } else { 3878 const char* tname = type2name(java_lang_Class::primitive_type(obj)); 3879 st->print("%s", tname ? tname : "type?"); 3880 } 3881 } else if (this == vmClasses::MethodType_klass()) { 3882 st->print(" = "); 3883 java_lang_invoke_MethodType::print_signature(obj, st); 3884 } else if (java_lang_boxing_object::is_instance(obj)) { 3885 st->print(" = "); 3886 java_lang_boxing_object::print(obj, st); 3887 } else if (this == vmClasses::LambdaForm_klass()) { 3888 oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj); 3889 if (vmentry != nullptr) { 3890 st->print(" => "); 3891 vmentry->print_value_on(st); 3892 } 3893 } else if (this == vmClasses::MemberName_klass()) { 3894 Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj); 3895 if (vmtarget != nullptr) { 3896 st->print(" = "); 3897 vmtarget->print_value_on(st); 3898 } else { 3899 oop clazz = java_lang_invoke_MemberName::clazz(obj); 3900 oop name = java_lang_invoke_MemberName::name(obj); 3901 if (clazz != nullptr) { 3902 clazz->print_value_on(st); 3903 } else { 3904 st->print("null"); 3905 } 3906 st->print("."); 3907 if (name != nullptr) { 3908 name->print_value_on(st); 3909 } else { 3910 st->print("null"); 3911 } 3912 } 3913 } 3914 } 3915 3916 const char* InstanceKlass::internal_name() const { 3917 return external_name(); 3918 } 3919 3920 void InstanceKlass::print_class_load_logging(ClassLoaderData* loader_data, 3921 const ModuleEntry* module_entry, 3922 const ClassFileStream* cfs) const { 3923 3924 if (ClassListWriter::is_enabled()) { 3925 ClassListWriter::write(this, cfs); 3926 } 3927 3928 print_class_load_helper(loader_data, module_entry, cfs); 3929 print_class_load_cause_logging(); 3930 } 3931 3932 void InstanceKlass::print_class_load_helper(ClassLoaderData* loader_data, 3933 const ModuleEntry* module_entry, 3934 const ClassFileStream* cfs) const { 3935 3936 if (!log_is_enabled(Info, class, load)) { 3937 return; 3938 } 3939 3940 ResourceMark rm; 3941 LogMessage(class, load) msg; 3942 stringStream info_stream; 3943 3944 // Name and class hierarchy info 3945 info_stream.print("%s", external_name()); 3946 3947 // Source 3948 if (cfs != nullptr) { 3949 if (cfs->source() != nullptr) { 3950 const char* module_name = (module_entry->name() == nullptr) ? UNNAMED_MODULE : module_entry->name()->as_C_string(); 3951 if (module_name != nullptr) { 3952 // When the boot loader created the stream, it didn't know the module name 3953 // yet. Let's format it now. 3954 if (cfs->from_boot_loader_modules_image()) { 3955 info_stream.print(" source: jrt:/%s", module_name); 3956 } else { 3957 info_stream.print(" source: %s", cfs->source()); 3958 } 3959 } else { 3960 info_stream.print(" source: %s", cfs->source()); 3961 } 3962 } else if (loader_data == ClassLoaderData::the_null_class_loader_data()) { 3963 Thread* current = Thread::current(); 3964 Klass* caller = current->is_Java_thread() ? 3965 JavaThread::cast(current)->security_get_caller_class(1): 3966 nullptr; 3967 // caller can be null, for example, during a JVMTI VM_Init hook 3968 if (caller != nullptr) { 3969 info_stream.print(" source: instance of %s", caller->external_name()); 3970 } else { 3971 // source is unknown 3972 } 3973 } else { 3974 oop class_loader = loader_data->class_loader(); 3975 info_stream.print(" source: %s", class_loader->klass()->external_name()); 3976 } 3977 } else { 3978 assert(this->is_shared(), "must be"); 3979 if (MetaspaceShared::is_shared_dynamic((void*)this)) { 3980 info_stream.print(" source: shared objects file (top)"); 3981 } else { 3982 info_stream.print(" source: shared objects file"); 3983 } 3984 } 3985 3986 msg.info("%s", info_stream.as_string()); 3987 3988 if (log_is_enabled(Debug, class, load)) { 3989 stringStream debug_stream; 3990 3991 // Class hierarchy info 3992 debug_stream.print(" klass: " PTR_FORMAT " super: " PTR_FORMAT, 3993 p2i(this), p2i(superklass())); 3994 3995 // Interfaces 3996 if (local_interfaces() != nullptr && local_interfaces()->length() > 0) { 3997 debug_stream.print(" interfaces:"); 3998 int length = local_interfaces()->length(); 3999 for (int i = 0; i < length; i++) { 4000 debug_stream.print(" " PTR_FORMAT, 4001 p2i(InstanceKlass::cast(local_interfaces()->at(i)))); 4002 } 4003 } 4004 4005 // Class loader 4006 debug_stream.print(" loader: ["); 4007 loader_data->print_value_on(&debug_stream); 4008 debug_stream.print("]"); 4009 4010 // Classfile checksum 4011 if (cfs) { 4012 debug_stream.print(" bytes: %d checksum: %08x", 4013 cfs->length(), 4014 ClassLoader::crc32(0, (const char*)cfs->buffer(), 4015 cfs->length())); 4016 } 4017 4018 msg.debug("%s", debug_stream.as_string()); 4019 } 4020 } 4021 4022 void InstanceKlass::print_class_load_cause_logging() const { 4023 bool log_cause_native = log_is_enabled(Info, class, load, cause, native); 4024 if (log_cause_native || log_is_enabled(Info, class, load, cause)) { 4025 JavaThread* current = JavaThread::current(); 4026 ResourceMark rm(current); 4027 const char* name = external_name(); 4028 4029 if (LogClassLoadingCauseFor == nullptr || 4030 (strcmp("*", LogClassLoadingCauseFor) != 0 && 4031 strstr(name, LogClassLoadingCauseFor) == nullptr)) { 4032 return; 4033 } 4034 4035 // Log Java stack first 4036 { 4037 LogMessage(class, load, cause) msg; 4038 NonInterleavingLogStream info_stream{LogLevelType::Info, msg}; 4039 4040 info_stream.print_cr("Java stack when loading %s:", name); 4041 current->print_stack_on(&info_stream); 4042 } 4043 4044 // Log native stack second 4045 if (log_cause_native) { 4046 // Log to string first so that lines can be indented 4047 stringStream stack_stream; 4048 char buf[O_BUFLEN]; 4049 address lastpc = nullptr; 4050 NativeStackPrinter nsp(current); 4051 nsp.print_stack(&stack_stream, buf, sizeof(buf), lastpc, 4052 true /* print_source_info */, -1 /* max stack */); 4053 4054 LogMessage(class, load, cause, native) msg; 4055 NonInterleavingLogStream info_stream{LogLevelType::Info, msg}; 4056 info_stream.print_cr("Native stack when loading %s:", name); 4057 4058 // Print each native stack line to the log 4059 int size = (int) stack_stream.size(); 4060 char* stack = stack_stream.as_string(); 4061 char* stack_end = stack + size; 4062 char* line_start = stack; 4063 for (char* p = stack; p < stack_end; p++) { 4064 if (*p == '\n') { 4065 *p = '\0'; 4066 info_stream.print_cr("\t%s", line_start); 4067 line_start = p + 1; 4068 } 4069 } 4070 if (line_start < stack_end) { 4071 info_stream.print_cr("\t%s", line_start); 4072 } 4073 } 4074 } 4075 } 4076 4077 // Verification 4078 4079 class VerifyFieldClosure: public BasicOopIterateClosure { 4080 protected: 4081 template <class T> void do_oop_work(T* p) { 4082 oop obj = RawAccess<>::oop_load(p); 4083 if (!oopDesc::is_oop_or_null(obj)) { 4084 tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p2i(p), p2i(obj)); 4085 Universe::print_on(tty); 4086 guarantee(false, "boom"); 4087 } 4088 } 4089 public: 4090 virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); } 4091 virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); } 4092 }; 4093 4094 void InstanceKlass::verify_on(outputStream* st) { 4095 #ifndef PRODUCT 4096 // Avoid redundant verifies, this really should be in product. 4097 if (_verify_count == Universe::verify_count()) return; 4098 _verify_count = Universe::verify_count(); 4099 #endif 4100 4101 // Verify Klass 4102 Klass::verify_on(st); 4103 4104 // Verify that klass is present in ClassLoaderData 4105 guarantee(class_loader_data()->contains_klass(this), 4106 "this class isn't found in class loader data"); 4107 4108 // Verify vtables 4109 if (is_linked()) { 4110 // $$$ This used to be done only for m/s collections. Doing it 4111 // always seemed a valid generalization. (DLD -- 6/00) 4112 vtable().verify(st); 4113 } 4114 4115 // Verify first subklass 4116 if (subklass() != nullptr) { 4117 guarantee(subklass()->is_klass(), "should be klass"); 4118 } 4119 4120 // Verify siblings 4121 Klass* super = this->super(); 4122 Klass* sib = next_sibling(); 4123 if (sib != nullptr) { 4124 if (sib == this) { 4125 fatal("subclass points to itself " PTR_FORMAT, p2i(sib)); 4126 } 4127 4128 guarantee(sib->is_klass(), "should be klass"); 4129 guarantee(sib->super() == super, "siblings should have same superklass"); 4130 } 4131 4132 // Verify local interfaces 4133 if (local_interfaces()) { 4134 Array<InstanceKlass*>* local_interfaces = this->local_interfaces(); 4135 for (int j = 0; j < local_interfaces->length(); j++) { 4136 InstanceKlass* e = local_interfaces->at(j); 4137 guarantee(e->is_klass() && e->is_interface(), "invalid local interface"); 4138 } 4139 } 4140 4141 // Verify transitive interfaces 4142 if (transitive_interfaces() != nullptr) { 4143 Array<InstanceKlass*>* transitive_interfaces = this->transitive_interfaces(); 4144 for (int j = 0; j < transitive_interfaces->length(); j++) { 4145 InstanceKlass* e = transitive_interfaces->at(j); 4146 guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface"); 4147 } 4148 } 4149 4150 // Verify methods 4151 if (methods() != nullptr) { 4152 Array<Method*>* methods = this->methods(); 4153 for (int j = 0; j < methods->length(); j++) { 4154 guarantee(methods->at(j)->is_method(), "non-method in methods array"); 4155 } 4156 for (int j = 0; j < methods->length() - 1; j++) { 4157 Method* m1 = methods->at(j); 4158 Method* m2 = methods->at(j + 1); 4159 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly"); 4160 } 4161 } 4162 4163 // Verify method ordering 4164 if (method_ordering() != nullptr) { 4165 Array<int>* method_ordering = this->method_ordering(); 4166 int length = method_ordering->length(); 4167 if (JvmtiExport::can_maintain_original_method_order() || 4168 ((CDSConfig::is_using_archive() || CDSConfig::is_dumping_archive()) && length != 0)) { 4169 guarantee(length == methods()->length(), "invalid method ordering length"); 4170 jlong sum = 0; 4171 for (int j = 0; j < length; j++) { 4172 int original_index = method_ordering->at(j); 4173 guarantee(original_index >= 0, "invalid method ordering index"); 4174 guarantee(original_index < length, "invalid method ordering index"); 4175 sum += original_index; 4176 } 4177 // Verify sum of indices 0,1,...,length-1 4178 guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum"); 4179 } else { 4180 guarantee(length == 0, "invalid method ordering length"); 4181 } 4182 } 4183 4184 // Verify default methods 4185 if (default_methods() != nullptr) { 4186 Array<Method*>* methods = this->default_methods(); 4187 for (int j = 0; j < methods->length(); j++) { 4188 guarantee(methods->at(j)->is_method(), "non-method in methods array"); 4189 } 4190 for (int j = 0; j < methods->length() - 1; j++) { 4191 Method* m1 = methods->at(j); 4192 Method* m2 = methods->at(j + 1); 4193 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly"); 4194 } 4195 } 4196 4197 // Verify JNI static field identifiers 4198 if (jni_ids() != nullptr) { 4199 jni_ids()->verify(this); 4200 } 4201 4202 // Verify other fields 4203 if (constants() != nullptr) { 4204 guarantee(constants()->is_constantPool(), "should be constant pool"); 4205 } 4206 } 4207 4208 void InstanceKlass::oop_verify_on(oop obj, outputStream* st) { 4209 Klass::oop_verify_on(obj, st); 4210 VerifyFieldClosure blk; 4211 obj->oop_iterate(&blk); 4212 } 4213 4214 4215 // JNIid class for jfieldIDs only 4216 // Note to reviewers: 4217 // These JNI functions are just moved over to column 1 and not changed 4218 // in the compressed oops workspace. 4219 JNIid::JNIid(Klass* holder, int offset, JNIid* next) { 4220 _holder = holder; 4221 _offset = offset; 4222 _next = next; 4223 DEBUG_ONLY(_is_static_field_id = false;) 4224 } 4225 4226 4227 JNIid* JNIid::find(int offset) { 4228 JNIid* current = this; 4229 while (current != nullptr) { 4230 if (current->offset() == offset) return current; 4231 current = current->next(); 4232 } 4233 return nullptr; 4234 } 4235 4236 void JNIid::deallocate(JNIid* current) { 4237 while (current != nullptr) { 4238 JNIid* next = current->next(); 4239 delete current; 4240 current = next; 4241 } 4242 } 4243 4244 4245 void JNIid::verify(Klass* holder) { 4246 int first_field_offset = InstanceMirrorKlass::offset_of_static_fields(); 4247 int end_field_offset; 4248 end_field_offset = first_field_offset + (InstanceKlass::cast(holder)->static_field_size() * wordSize); 4249 4250 JNIid* current = this; 4251 while (current != nullptr) { 4252 guarantee(current->holder() == holder, "Invalid klass in JNIid"); 4253 #ifdef ASSERT 4254 int o = current->offset(); 4255 if (current->is_static_field_id()) { 4256 guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid"); 4257 } 4258 #endif 4259 current = current->next(); 4260 } 4261 } 4262 4263 void InstanceKlass::set_init_state(ClassState state) { 4264 #ifdef ASSERT 4265 bool good_state = is_shared() ? (_init_state <= state) 4266 : (_init_state < state); 4267 assert(good_state || state == allocated, "illegal state transition"); 4268 #endif 4269 assert(_init_thread == nullptr, "should be cleared before state change"); 4270 Atomic::release_store(&_init_state, state); 4271 } 4272 4273 #if INCLUDE_JVMTI 4274 4275 // RedefineClasses() support for previous versions 4276 4277 // Globally, there is at least one previous version of a class to walk 4278 // during class unloading, which is saved because old methods in the class 4279 // are still running. Otherwise the previous version list is cleaned up. 4280 bool InstanceKlass::_should_clean_previous_versions = false; 4281 4282 // Returns true if there are previous versions of a class for class 4283 // unloading only. Also resets the flag to false. purge_previous_version 4284 // will set the flag to true if there are any left, i.e., if there's any 4285 // work to do for next time. This is to avoid the expensive code cache 4286 // walk in CLDG::clean_deallocate_lists(). 4287 bool InstanceKlass::should_clean_previous_versions_and_reset() { 4288 bool ret = _should_clean_previous_versions; 4289 log_trace(redefine, class, iklass, purge)("Class unloading: should_clean_previous_versions = %s", 4290 ret ? "true" : "false"); 4291 _should_clean_previous_versions = false; 4292 return ret; 4293 } 4294 4295 // This nulls out the jmethodID for all obsolete methods in the previous version of the 'klass'. 4296 // These obsolete methods only exist in the previous version and we're about to delete the memory for them. 4297 // The jmethodID for these are deallocated when we unload the class, so this doesn't remove them from the table. 4298 void InstanceKlass::clear_obsolete_jmethod_ids(InstanceKlass* klass) { 4299 Array<Method*>* method_refs = klass->methods(); 4300 for (int k = 0; k < method_refs->length(); k++) { 4301 Method* method = method_refs->at(k); 4302 // Only need to clear obsolete methods. 4303 if (method != nullptr && method->is_obsolete()) { 4304 method->clear_jmethod_id(); 4305 } 4306 } 4307 } 4308 4309 // Purge previous versions before adding new previous versions of the class and 4310 // during class unloading. 4311 void InstanceKlass::purge_previous_version_list() { 4312 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint"); 4313 assert(has_been_redefined(), "Should only be called for main class"); 4314 4315 // Quick exit. 4316 if (previous_versions() == nullptr) { 4317 return; 4318 } 4319 4320 // This klass has previous versions so see what we can cleanup 4321 // while it is safe to do so. 4322 4323 int deleted_count = 0; // leave debugging breadcrumbs 4324 int live_count = 0; 4325 ClassLoaderData* loader_data = class_loader_data(); 4326 assert(loader_data != nullptr, "should never be null"); 4327 4328 ResourceMark rm; 4329 log_trace(redefine, class, iklass, purge)("%s: previous versions", external_name()); 4330 4331 // previous versions are linked together through the InstanceKlass 4332 InstanceKlass* pv_node = previous_versions(); 4333 InstanceKlass* last = this; 4334 int version = 0; 4335 4336 // check the previous versions list 4337 for (; pv_node != nullptr; ) { 4338 4339 ConstantPool* pvcp = pv_node->constants(); 4340 assert(pvcp != nullptr, "cp ref was unexpectedly cleared"); 4341 4342 if (!pvcp->on_stack()) { 4343 // If the constant pool isn't on stack, none of the methods 4344 // are executing. Unlink this previous_version. 4345 // The previous version InstanceKlass is on the ClassLoaderData deallocate list 4346 // so will be deallocated during the next phase of class unloading. 4347 log_trace(redefine, class, iklass, purge) 4348 ("previous version " PTR_FORMAT " is dead.", p2i(pv_node)); 4349 // Unlink from previous version list. 4350 assert(pv_node->class_loader_data() == loader_data, "wrong loader_data"); 4351 InstanceKlass* next = pv_node->previous_versions(); 4352 clear_obsolete_jmethod_ids(pv_node); // jmethodID maintenance for the unloaded class 4353 pv_node->link_previous_versions(nullptr); // point next to null 4354 last->link_previous_versions(next); 4355 // Delete this node directly. Nothing is referring to it and we don't 4356 // want it to increase the counter for metadata to delete in CLDG. 4357 MetadataFactory::free_metadata(loader_data, pv_node); 4358 pv_node = next; 4359 deleted_count++; 4360 version++; 4361 continue; 4362 } else { 4363 assert(pvcp->pool_holder() != nullptr, "Constant pool with no holder"); 4364 guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack"); 4365 live_count++; 4366 if (pvcp->is_shared()) { 4367 // Shared previous versions can never be removed so no cleaning is needed. 4368 log_trace(redefine, class, iklass, purge)("previous version " PTR_FORMAT " is shared", p2i(pv_node)); 4369 } else { 4370 // Previous version alive, set that clean is needed for next time. 4371 _should_clean_previous_versions = true; 4372 log_trace(redefine, class, iklass, purge)("previous version " PTR_FORMAT " is alive", p2i(pv_node)); 4373 } 4374 } 4375 4376 // next previous version 4377 last = pv_node; 4378 pv_node = pv_node->previous_versions(); 4379 version++; 4380 } 4381 log_trace(redefine, class, iklass, purge) 4382 ("previous version stats: live=%d, deleted=%d", live_count, deleted_count); 4383 } 4384 4385 void InstanceKlass::mark_newly_obsolete_methods(Array<Method*>* old_methods, 4386 int emcp_method_count) { 4387 int obsolete_method_count = old_methods->length() - emcp_method_count; 4388 4389 if (emcp_method_count != 0 && obsolete_method_count != 0 && 4390 _previous_versions != nullptr) { 4391 // We have a mix of obsolete and EMCP methods so we have to 4392 // clear out any matching EMCP method entries the hard way. 4393 int local_count = 0; 4394 for (int i = 0; i < old_methods->length(); i++) { 4395 Method* old_method = old_methods->at(i); 4396 if (old_method->is_obsolete()) { 4397 // only obsolete methods are interesting 4398 Symbol* m_name = old_method->name(); 4399 Symbol* m_signature = old_method->signature(); 4400 4401 // previous versions are linked together through the InstanceKlass 4402 int j = 0; 4403 for (InstanceKlass* prev_version = _previous_versions; 4404 prev_version != nullptr; 4405 prev_version = prev_version->previous_versions(), j++) { 4406 4407 Array<Method*>* method_refs = prev_version->methods(); 4408 for (int k = 0; k < method_refs->length(); k++) { 4409 Method* method = method_refs->at(k); 4410 4411 if (!method->is_obsolete() && 4412 method->name() == m_name && 4413 method->signature() == m_signature) { 4414 // The current RedefineClasses() call has made all EMCP 4415 // versions of this method obsolete so mark it as obsolete 4416 log_trace(redefine, class, iklass, add) 4417 ("%s(%s): flush obsolete method @%d in version @%d", 4418 m_name->as_C_string(), m_signature->as_C_string(), k, j); 4419 4420 method->set_is_obsolete(); 4421 break; 4422 } 4423 } 4424 4425 // The previous loop may not find a matching EMCP method, but 4426 // that doesn't mean that we can optimize and not go any 4427 // further back in the PreviousVersion generations. The EMCP 4428 // method for this generation could have already been made obsolete, 4429 // but there still may be an older EMCP method that has not 4430 // been made obsolete. 4431 } 4432 4433 if (++local_count >= obsolete_method_count) { 4434 // no more obsolete methods so bail out now 4435 break; 4436 } 4437 } 4438 } 4439 } 4440 } 4441 4442 // Save the scratch_class as the previous version if any of the methods are running. 4443 // The previous_versions are used to set breakpoints in EMCP methods and they are 4444 // also used to clean MethodData links to redefined methods that are no longer running. 4445 void InstanceKlass::add_previous_version(InstanceKlass* scratch_class, 4446 int emcp_method_count) { 4447 assert(Thread::current()->is_VM_thread(), 4448 "only VMThread can add previous versions"); 4449 4450 ResourceMark rm; 4451 log_trace(redefine, class, iklass, add) 4452 ("adding previous version ref for %s, EMCP_cnt=%d", scratch_class->external_name(), emcp_method_count); 4453 4454 // Clean out old previous versions for this class 4455 purge_previous_version_list(); 4456 4457 // Mark newly obsolete methods in remaining previous versions. An EMCP method from 4458 // a previous redefinition may be made obsolete by this redefinition. 4459 Array<Method*>* old_methods = scratch_class->methods(); 4460 mark_newly_obsolete_methods(old_methods, emcp_method_count); 4461 4462 // If the constant pool for this previous version of the class 4463 // is not marked as being on the stack, then none of the methods 4464 // in this previous version of the class are on the stack so 4465 // we don't need to add this as a previous version. 4466 ConstantPool* cp_ref = scratch_class->constants(); 4467 if (!cp_ref->on_stack()) { 4468 log_trace(redefine, class, iklass, add)("scratch class not added; no methods are running"); 4469 scratch_class->class_loader_data()->add_to_deallocate_list(scratch_class); 4470 return; 4471 } 4472 4473 // Add previous version if any methods are still running or if this is 4474 // a shared class which should never be removed. 4475 assert(scratch_class->previous_versions() == nullptr, "shouldn't have a previous version"); 4476 scratch_class->link_previous_versions(previous_versions()); 4477 link_previous_versions(scratch_class); 4478 if (cp_ref->is_shared()) { 4479 log_trace(redefine, class, iklass, add) ("scratch class added; class is shared"); 4480 } else { 4481 // We only set clean_previous_versions flag for processing during class 4482 // unloading for non-shared classes. 4483 _should_clean_previous_versions = true; 4484 log_trace(redefine, class, iklass, add) ("scratch class added; one of its methods is on_stack."); 4485 } 4486 } // end add_previous_version() 4487 4488 #endif // INCLUDE_JVMTI 4489 4490 Method* InstanceKlass::method_with_idnum(int idnum) const { 4491 Method* m = nullptr; 4492 if (idnum < methods()->length()) { 4493 m = methods()->at(idnum); 4494 } 4495 if (m == nullptr || m->method_idnum() != idnum) { 4496 for (int index = 0; index < methods()->length(); ++index) { 4497 m = methods()->at(index); 4498 if (m->method_idnum() == idnum) { 4499 return m; 4500 } 4501 } 4502 // None found, return null for the caller to handle. 4503 return nullptr; 4504 } 4505 return m; 4506 } 4507 4508 4509 Method* InstanceKlass::method_with_orig_idnum(int idnum) const { 4510 if (idnum >= methods()->length()) { 4511 return nullptr; 4512 } 4513 Method* m = methods()->at(idnum); 4514 if (m != nullptr && m->orig_method_idnum() == idnum) { 4515 return m; 4516 } 4517 // Obsolete method idnum does not match the original idnum 4518 for (int index = 0; index < methods()->length(); ++index) { 4519 m = methods()->at(index); 4520 if (m->orig_method_idnum() == idnum) { 4521 return m; 4522 } 4523 } 4524 // None found, return null for the caller to handle. 4525 return nullptr; 4526 } 4527 4528 4529 Method* InstanceKlass::method_with_orig_idnum(int idnum, int version) const { 4530 const InstanceKlass* holder = get_klass_version(version); 4531 if (holder == nullptr) { 4532 return nullptr; // The version of klass is gone, no method is found 4533 } 4534 return holder->method_with_orig_idnum(idnum); 4535 } 4536 4537 #if INCLUDE_JVMTI 4538 JvmtiCachedClassFileData* InstanceKlass::get_cached_class_file() { 4539 return _cached_class_file; 4540 } 4541 4542 jint InstanceKlass::get_cached_class_file_len() { 4543 return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file); 4544 } 4545 4546 unsigned char * InstanceKlass::get_cached_class_file_bytes() { 4547 return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file); 4548 } 4549 #endif 4550 4551 // Make a step iterating over the class hierarchy under the root class. 4552 // Skips subclasses if requested. 4553 void ClassHierarchyIterator::next() { 4554 assert(_current != nullptr, "required"); 4555 if (_visit_subclasses && _current->subklass() != nullptr) { 4556 _current = _current->subklass(); 4557 return; // visit next subclass 4558 } 4559 _visit_subclasses = true; // reset 4560 while (_current->next_sibling() == nullptr && _current != _root) { 4561 _current = _current->superklass(); // backtrack; no more sibling subclasses left 4562 } 4563 if (_current == _root) { 4564 // Iteration is over (back at root after backtracking). Invalidate the iterator. 4565 _current = nullptr; 4566 return; 4567 } 4568 _current = _current->next_sibling(); 4569 return; // visit next sibling subclass 4570 }