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 (fields_status() != nullptr && !fields_status()->is_shared()) { 690 MetadataFactory::free_array<FieldStatus>(loader_data, fields_status()); 691 } 692 set_fields_status(nullptr); 693 694 // If a method from a redefined class is using this constant pool, don't 695 // delete it, yet. The new class's previous version will point to this. 696 if (constants() != nullptr) { 697 assert (!constants()->on_stack(), "shouldn't be called if anything is onstack"); 698 if (!constants()->is_shared()) { 699 MetadataFactory::free_metadata(loader_data, constants()); 700 } 701 // Delete any cached resolution errors for the constant pool 702 SystemDictionary::delete_resolution_error(constants()); 703 704 set_constants(nullptr); 705 } 706 707 if (inner_classes() != nullptr && 708 inner_classes() != Universe::the_empty_short_array() && 709 !inner_classes()->is_shared()) { 710 MetadataFactory::free_array<jushort>(loader_data, inner_classes()); 711 } 712 set_inner_classes(nullptr); 713 714 if (nest_members() != nullptr && 715 nest_members() != Universe::the_empty_short_array() && 716 !nest_members()->is_shared()) { 717 MetadataFactory::free_array<jushort>(loader_data, nest_members()); 718 } 719 set_nest_members(nullptr); 720 721 if (permitted_subclasses() != nullptr && 722 permitted_subclasses() != Universe::the_empty_short_array() && 723 !permitted_subclasses()->is_shared()) { 724 MetadataFactory::free_array<jushort>(loader_data, permitted_subclasses()); 725 } 726 set_permitted_subclasses(nullptr); 727 728 // We should deallocate the Annotations instance if it's not in shared spaces. 729 if (annotations() != nullptr && !annotations()->is_shared()) { 730 MetadataFactory::free_metadata(loader_data, annotations()); 731 } 732 set_annotations(nullptr); 733 734 SystemDictionaryShared::handle_class_unloading(this); 735 736 #if INCLUDE_CDS_JAVA_HEAP 737 if (CDSConfig::is_dumping_heap()) { 738 HeapShared::remove_scratch_objects(this); 739 } 740 #endif 741 } 742 743 bool InstanceKlass::is_record() const { 744 return _record_components != nullptr && 745 is_final() && 746 java_super() == vmClasses::Record_klass(); 747 } 748 749 bool InstanceKlass::is_sealed() const { 750 return _permitted_subclasses != nullptr && 751 _permitted_subclasses != Universe::the_empty_short_array(); 752 } 753 754 // JLS 8.9: An enum class is either implicitly final and derives 755 // from java.lang.Enum, or else is implicitly sealed to its 756 // anonymous subclasses. This query detects both kinds. 757 // It does not validate the finality or 758 // sealing conditions: it merely checks for a super of Enum. 759 // This is sufficient for recognizing well-formed enums. 760 bool InstanceKlass::is_enum_subclass() const { 761 InstanceKlass* s = java_super(); 762 return (s == vmClasses::Enum_klass() || 763 (s != nullptr && s->java_super() == vmClasses::Enum_klass())); 764 } 765 766 bool InstanceKlass::should_be_initialized() const { 767 return !is_initialized(); 768 } 769 770 klassItable InstanceKlass::itable() const { 771 return klassItable(const_cast<InstanceKlass*>(this)); 772 } 773 774 // JVMTI spec thinks there are signers and protection domain in the 775 // instanceKlass. These accessors pretend these fields are there. 776 // The hprof specification also thinks these fields are in InstanceKlass. 777 oop InstanceKlass::protection_domain() const { 778 // return the protection_domain from the mirror 779 return java_lang_Class::protection_domain(java_mirror()); 780 } 781 782 objArrayOop InstanceKlass::signers() const { 783 // return the signers from the mirror 784 return java_lang_Class::signers(java_mirror()); 785 } 786 787 oop InstanceKlass::init_lock() const { 788 // return the init lock from the mirror 789 oop lock = java_lang_Class::init_lock(java_mirror()); 790 // Prevent reordering with any access of initialization state 791 OrderAccess::loadload(); 792 assert(lock != nullptr || !is_not_initialized(), // initialized or in_error state 793 "only fully initialized state can have a null lock"); 794 return lock; 795 } 796 797 // Set the initialization lock to null so the object can be GC'ed. Any racing 798 // threads to get this lock will see a null lock and will not lock. 799 // That's okay because they all check for initialized state after getting 800 // the lock and return. 801 void InstanceKlass::fence_and_clear_init_lock() { 802 // make sure previous stores are all done, notably the init_state. 803 OrderAccess::storestore(); 804 java_lang_Class::clear_init_lock(java_mirror()); 805 assert(!is_not_initialized(), "class must be initialized now"); 806 } 807 808 809 // See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization 810 // process. The step comments refers to the procedure described in that section. 811 // Note: implementation moved to static method to expose the this pointer. 812 void InstanceKlass::initialize(TRAPS) { 813 if (this->should_be_initialized()) { 814 initialize_impl(CHECK); 815 // Note: at this point the class may be initialized 816 // OR it may be in the state of being initialized 817 // in case of recursive initialization! 818 } else { 819 assert(is_initialized(), "sanity check"); 820 } 821 } 822 823 #ifdef ASSERT 824 void InstanceKlass::assert_no_clinit_will_run_for_aot_initialized_class() const { 825 assert(has_aot_initialized_mirror(), "must be"); 826 827 InstanceKlass* s = java_super(); 828 if (s != nullptr) { 829 DEBUG_ONLY(ResourceMark rm); 830 assert(s->is_initialized(), "super class %s of aot-inited class %s must have been initialized", 831 s->external_name(), external_name()); 832 s->assert_no_clinit_will_run_for_aot_initialized_class(); 833 } 834 835 Array<InstanceKlass*>* interfaces = local_interfaces(); 836 int len = interfaces->length(); 837 for (int i = 0; i < len; i++) { 838 InstanceKlass* intf = interfaces->at(i); 839 if (!intf->is_initialized()) { 840 ResourceMark rm; 841 // Note: an interface needs to be marked as is_initialized() only if 842 // - it has a <clinit> 843 // - it has declared a default method. 844 assert(!intf->interface_needs_clinit_execution_as_super(/*also_check_supers*/false), 845 "uninitialized super interface %s of aot-inited class %s must not have <clinit>", 846 intf->external_name(), external_name()); 847 } 848 } 849 } 850 #endif 851 852 #if INCLUDE_CDS 853 void InstanceKlass::initialize_with_aot_initialized_mirror(TRAPS) { 854 assert(has_aot_initialized_mirror(), "must be"); 855 assert(CDSConfig::is_loading_heap(), "must be"); 856 assert(CDSConfig::is_using_aot_linked_classes(), "must be"); 857 assert_no_clinit_will_run_for_aot_initialized_class(); 858 859 if (is_initialized()) { 860 return; 861 } 862 863 if (is_runtime_setup_required()) { 864 // Need to take the slow path, which will call the runtimeSetup() function instead 865 // of <clinit> 866 initialize(CHECK); 867 return; 868 } 869 if (log_is_enabled(Info, aot, init)) { 870 ResourceMark rm; 871 log_info(aot, init)("%s (aot-inited)", external_name()); 872 } 873 874 link_class(CHECK); 875 876 #ifdef ASSERT 877 { 878 Handle h_init_lock(THREAD, init_lock()); 879 ObjectLocker ol(h_init_lock, THREAD); 880 assert(!is_initialized(), "sanity"); 881 assert(!is_being_initialized(), "sanity"); 882 assert(!is_in_error_state(), "sanity"); 883 } 884 #endif 885 886 set_init_thread(THREAD); 887 set_initialization_state_and_notify(fully_initialized, CHECK); 888 } 889 #endif 890 891 bool InstanceKlass::verify_code(TRAPS) { 892 // 1) Verify the bytecodes 893 return Verifier::verify(this, should_verify_class(), THREAD); 894 } 895 896 void InstanceKlass::link_class(TRAPS) { 897 assert(is_loaded(), "must be loaded"); 898 if (!is_linked()) { 899 link_class_impl(CHECK); 900 } 901 } 902 903 // Called to verify that a class can link during initialization, without 904 // throwing a VerifyError. 905 bool InstanceKlass::link_class_or_fail(TRAPS) { 906 assert(is_loaded(), "must be loaded"); 907 if (!is_linked()) { 908 link_class_impl(CHECK_false); 909 } 910 return is_linked(); 911 } 912 913 bool InstanceKlass::link_class_impl(TRAPS) { 914 if (CDSConfig::is_dumping_static_archive() && SystemDictionaryShared::has_class_failed_verification(this)) { 915 // This is for CDS static dump only -- we use the in_error_state to indicate that 916 // the class has failed verification. Throwing the NoClassDefFoundError here is just 917 // a convenient way to stop repeat attempts to verify the same (bad) class. 918 // 919 // Note that the NoClassDefFoundError is not part of the JLS, and should not be thrown 920 // if we are executing Java code. This is not a problem for CDS dumping phase since 921 // it doesn't execute any Java code. 922 ResourceMark rm(THREAD); 923 // Names are all known to be < 64k so we know this formatted message is not excessively large. 924 Exceptions::fthrow(THREAD_AND_LOCATION, 925 vmSymbols::java_lang_NoClassDefFoundError(), 926 "Class %s, or one of its supertypes, failed class initialization", 927 external_name()); 928 return false; 929 } 930 // return if already verified 931 if (is_linked()) { 932 return true; 933 } 934 935 // Timing 936 // timer handles recursion 937 JavaThread* jt = THREAD; 938 939 // link super class before linking this class 940 Klass* super_klass = super(); 941 if (super_klass != nullptr) { 942 if (super_klass->is_interface()) { // check if super class is an interface 943 ResourceMark rm(THREAD); 944 // Names are all known to be < 64k so we know this formatted message is not excessively large. 945 Exceptions::fthrow( 946 THREAD_AND_LOCATION, 947 vmSymbols::java_lang_IncompatibleClassChangeError(), 948 "class %s has interface %s as super class", 949 external_name(), 950 super_klass->external_name() 951 ); 952 return false; 953 } 954 955 InstanceKlass* ik_super = InstanceKlass::cast(super_klass); 956 ik_super->link_class_impl(CHECK_false); 957 } 958 959 // link all interfaces implemented by this class before linking this class 960 Array<InstanceKlass*>* interfaces = local_interfaces(); 961 int num_interfaces = interfaces->length(); 962 for (int index = 0; index < num_interfaces; index++) { 963 InstanceKlass* interk = interfaces->at(index); 964 interk->link_class_impl(CHECK_false); 965 } 966 967 // in case the class is linked in the process of linking its superclasses 968 if (is_linked()) { 969 return true; 970 } 971 972 // trace only the link time for this klass that includes 973 // the verification time 974 PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(), 975 ClassLoader::perf_class_link_selftime(), 976 ClassLoader::perf_classes_linked(), 977 jt->get_thread_stat()->perf_recursion_counts_addr(), 978 jt->get_thread_stat()->perf_timers_addr(), 979 PerfClassTraceTime::CLASS_LINK); 980 981 // verification & rewriting 982 { 983 HandleMark hm(THREAD); 984 Handle h_init_lock(THREAD, init_lock()); 985 ObjectLocker ol(h_init_lock, jt); 986 // rewritten will have been set if loader constraint error found 987 // on an earlier link attempt 988 // don't verify or rewrite if already rewritten 989 // 990 991 if (!is_linked()) { 992 if (!is_rewritten()) { 993 if (is_shared()) { 994 assert(!verified_at_dump_time(), "must be"); 995 } 996 { 997 bool verify_ok = verify_code(THREAD); 998 if (!verify_ok) { 999 return false; 1000 } 1001 } 1002 1003 // Just in case a side-effect of verify linked this class already 1004 // (which can sometimes happen since the verifier loads classes 1005 // using custom class loaders, which are free to initialize things) 1006 if (is_linked()) { 1007 return true; 1008 } 1009 1010 // also sets rewritten 1011 rewrite_class(CHECK_false); 1012 } else if (is_shared()) { 1013 SystemDictionaryShared::check_verification_constraints(this, CHECK_false); 1014 } 1015 1016 // relocate jsrs and link methods after they are all rewritten 1017 link_methods(CHECK_false); 1018 1019 // Initialize the vtable and interface table after 1020 // methods have been rewritten since rewrite may 1021 // fabricate new Method*s. 1022 // also does loader constraint checking 1023 // 1024 // initialize_vtable and initialize_itable need to be rerun 1025 // for a shared class if 1026 // 1) the class is loaded by custom class loader or 1027 // 2) the class is loaded by built-in class loader but failed to add archived loader constraints or 1028 // 3) the class was not verified during dump time 1029 bool need_init_table = true; 1030 if (is_shared() && verified_at_dump_time() && 1031 SystemDictionaryShared::check_linking_constraints(THREAD, this)) { 1032 need_init_table = false; 1033 } 1034 if (need_init_table) { 1035 vtable().initialize_vtable_and_check_constraints(CHECK_false); 1036 itable().initialize_itable_and_check_constraints(CHECK_false); 1037 } 1038 #ifdef ASSERT 1039 vtable().verify(tty, true); 1040 // In case itable verification is ever added. 1041 // itable().verify(tty, true); 1042 #endif 1043 if (Universe::is_fully_initialized()) { 1044 DeoptimizationScope deopt_scope; 1045 { 1046 // Now mark all code that assumes the class is not linked. 1047 // Set state under the Compile_lock also. 1048 MutexLocker ml(THREAD, Compile_lock); 1049 1050 set_init_state(linked); 1051 CodeCache::mark_dependents_on(&deopt_scope, this); 1052 } 1053 // Perform the deopt handshake outside Compile_lock. 1054 deopt_scope.deoptimize_marked(); 1055 } else { 1056 set_init_state(linked); 1057 } 1058 if (JvmtiExport::should_post_class_prepare()) { 1059 JvmtiExport::post_class_prepare(THREAD, this); 1060 } 1061 } 1062 } 1063 return true; 1064 } 1065 1066 // Rewrite the byte codes of all of the methods of a class. 1067 // The rewriter must be called exactly once. Rewriting must happen after 1068 // verification but before the first method of the class is executed. 1069 void InstanceKlass::rewrite_class(TRAPS) { 1070 assert(is_loaded(), "must be loaded"); 1071 if (is_rewritten()) { 1072 assert(is_shared(), "rewriting an unshared class?"); 1073 return; 1074 } 1075 Rewriter::rewrite(this, CHECK); 1076 set_rewritten(); 1077 } 1078 1079 // Now relocate and link method entry points after class is rewritten. 1080 // This is outside is_rewritten flag. In case of an exception, it can be 1081 // executed more than once. 1082 void InstanceKlass::link_methods(TRAPS) { 1083 PerfTraceTime timer(ClassLoader::perf_ik_link_methods_time()); 1084 1085 int len = methods()->length(); 1086 for (int i = len-1; i >= 0; i--) { 1087 methodHandle m(THREAD, methods()->at(i)); 1088 1089 // Set up method entry points for compiler and interpreter . 1090 m->link_method(m, CHECK); 1091 } 1092 } 1093 1094 // Eagerly initialize superinterfaces that declare default methods (concrete instance: any access) 1095 void InstanceKlass::initialize_super_interfaces(TRAPS) { 1096 assert (has_nonstatic_concrete_methods(), "caller should have checked this"); 1097 for (int i = 0; i < local_interfaces()->length(); ++i) { 1098 InstanceKlass* ik = local_interfaces()->at(i); 1099 1100 // Initialization is depth first search ie. we start with top of the inheritance tree 1101 // has_nonstatic_concrete_methods drives searching superinterfaces since it 1102 // means has_nonstatic_concrete_methods in its superinterface hierarchy 1103 if (ik->has_nonstatic_concrete_methods()) { 1104 ik->initialize_super_interfaces(CHECK); 1105 } 1106 1107 // Only initialize() interfaces that "declare" concrete methods. 1108 if (ik->should_be_initialized() && ik->declares_nonstatic_concrete_methods()) { 1109 ik->initialize(CHECK); 1110 } 1111 } 1112 } 1113 1114 using InitializationErrorTable = ResourceHashtable<const InstanceKlass*, OopHandle, 107, AnyObj::C_HEAP, mtClass>; 1115 static InitializationErrorTable* _initialization_error_table; 1116 1117 void InstanceKlass::add_initialization_error(JavaThread* current, Handle exception) { 1118 // Create the same exception with a message indicating the thread name, 1119 // and the StackTraceElements. 1120 Handle init_error = java_lang_Throwable::create_initialization_error(current, exception); 1121 ResourceMark rm(current); 1122 if (init_error.is_null()) { 1123 log_trace(class, init)("Unable to create the desired initialization error for class %s", external_name()); 1124 1125 // We failed to create the new exception, most likely due to either out-of-memory or 1126 // a stackoverflow error. If the original exception was either of those then we save 1127 // the shared, pre-allocated, stackless, instance of that exception. 1128 if (exception->klass() == vmClasses::StackOverflowError_klass()) { 1129 log_debug(class, init)("Using shared StackOverflowError as initialization error for class %s", external_name()); 1130 init_error = Handle(current, Universe::class_init_stack_overflow_error()); 1131 } else if (exception->klass() == vmClasses::OutOfMemoryError_klass()) { 1132 log_debug(class, init)("Using shared OutOfMemoryError as initialization error for class %s", external_name()); 1133 init_error = Handle(current, Universe::class_init_out_of_memory_error()); 1134 } else { 1135 return; 1136 } 1137 } 1138 1139 MutexLocker ml(current, ClassInitError_lock); 1140 OopHandle elem = OopHandle(Universe::vm_global(), init_error()); 1141 bool created; 1142 if (_initialization_error_table == nullptr) { 1143 _initialization_error_table = new (mtClass) InitializationErrorTable(); 1144 } 1145 _initialization_error_table->put_if_absent(this, elem, &created); 1146 assert(created, "Initialization is single threaded"); 1147 log_trace(class, init)("Initialization error added for class %s", external_name()); 1148 } 1149 1150 oop InstanceKlass::get_initialization_error(JavaThread* current) { 1151 MutexLocker ml(current, ClassInitError_lock); 1152 if (_initialization_error_table == nullptr) { 1153 return nullptr; 1154 } 1155 OopHandle* h = _initialization_error_table->get(this); 1156 return (h != nullptr) ? h->resolve() : nullptr; 1157 } 1158 1159 // Need to remove entries for unloaded classes. 1160 void InstanceKlass::clean_initialization_error_table() { 1161 struct InitErrorTableCleaner { 1162 bool do_entry(const InstanceKlass* ik, OopHandle h) { 1163 if (!ik->is_loader_alive()) { 1164 h.release(Universe::vm_global()); 1165 return true; 1166 } else { 1167 return false; 1168 } 1169 } 1170 }; 1171 1172 assert_locked_or_safepoint(ClassInitError_lock); 1173 InitErrorTableCleaner cleaner; 1174 if (_initialization_error_table != nullptr) { 1175 _initialization_error_table->unlink(&cleaner); 1176 } 1177 } 1178 1179 void InstanceKlass::initialize_impl(TRAPS) { 1180 HandleMark hm(THREAD); 1181 1182 // Make sure klass is linked (verified) before initialization 1183 // A class could already be verified, since it has been reflected upon. 1184 link_class(CHECK); 1185 1186 DTRACE_CLASSINIT_PROBE(required, -1); 1187 1188 bool wait = false; 1189 1190 JavaThread* jt = THREAD; 1191 1192 bool debug_logging_enabled = log_is_enabled(Debug, class, init); 1193 1194 // refer to the JVM book page 47 for description of steps 1195 // Step 1 1196 { 1197 Handle h_init_lock(THREAD, init_lock()); 1198 ObjectLocker ol(h_init_lock, jt); 1199 1200 // Step 2 1201 // If we were to use wait() instead of waitInterruptibly() then 1202 // we might end up throwing IE from link/symbol resolution sites 1203 // that aren't expected to throw. This would wreak havoc. See 6320309. 1204 while (is_being_initialized() && !is_reentrant_initialization(jt)) { 1205 if (debug_logging_enabled) { 1206 ResourceMark rm(jt); 1207 log_debug(class, init)("Thread \"%s\" waiting for initialization of %s by thread \"%s\"", 1208 jt->name(), external_name(), init_thread_name()); 1209 } 1210 wait = true; 1211 jt->set_class_to_be_initialized(this); 1212 ol.wait_uninterruptibly(jt); 1213 jt->set_class_to_be_initialized(nullptr); 1214 } 1215 1216 // Step 3 1217 if (is_being_initialized() && is_reentrant_initialization(jt)) { 1218 if (debug_logging_enabled) { 1219 ResourceMark rm(jt); 1220 log_debug(class, init)("Thread \"%s\" recursively initializing %s", 1221 jt->name(), external_name()); 1222 } 1223 DTRACE_CLASSINIT_PROBE_WAIT(recursive, -1, wait); 1224 return; 1225 } 1226 1227 // Step 4 1228 if (is_initialized()) { 1229 if (debug_logging_enabled) { 1230 ResourceMark rm(jt); 1231 log_debug(class, init)("Thread \"%s\" found %s already initialized", 1232 jt->name(), external_name()); 1233 } 1234 DTRACE_CLASSINIT_PROBE_WAIT(concurrent, -1, wait); 1235 return; 1236 } 1237 1238 // Step 5 1239 if (is_in_error_state()) { 1240 if (debug_logging_enabled) { 1241 ResourceMark rm(jt); 1242 log_debug(class, init)("Thread \"%s\" found %s is in error state", 1243 jt->name(), external_name()); 1244 } 1245 1246 DTRACE_CLASSINIT_PROBE_WAIT(erroneous, -1, wait); 1247 ResourceMark rm(THREAD); 1248 Handle cause(THREAD, get_initialization_error(THREAD)); 1249 1250 stringStream ss; 1251 ss.print("Could not initialize class %s", external_name()); 1252 if (cause.is_null()) { 1253 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), ss.as_string()); 1254 } else { 1255 THROW_MSG_CAUSE(vmSymbols::java_lang_NoClassDefFoundError(), 1256 ss.as_string(), cause); 1257 } 1258 } else { 1259 1260 // Step 6 1261 set_init_state(being_initialized); 1262 set_init_thread(jt); 1263 if (debug_logging_enabled) { 1264 ResourceMark rm(jt); 1265 log_debug(class, init)("Thread \"%s\" is initializing %s", 1266 jt->name(), external_name()); 1267 } 1268 } 1269 } 1270 1271 // Step 7 1272 // Next, if C is a class rather than an interface, initialize it's super class and super 1273 // interfaces. 1274 if (!is_interface()) { 1275 Klass* super_klass = super(); 1276 if (super_klass != nullptr && super_klass->should_be_initialized()) { 1277 super_klass->initialize(THREAD); 1278 } 1279 // If C implements any interface that declares a non-static, concrete method, 1280 // the initialization of C triggers initialization of its super interfaces. 1281 // Only need to recurse if has_nonstatic_concrete_methods which includes declaring and 1282 // having a superinterface that declares, non-static, concrete methods 1283 if (!HAS_PENDING_EXCEPTION && has_nonstatic_concrete_methods()) { 1284 initialize_super_interfaces(THREAD); 1285 } 1286 1287 // If any exceptions, complete abruptly, throwing the same exception as above. 1288 if (HAS_PENDING_EXCEPTION) { 1289 Handle e(THREAD, PENDING_EXCEPTION); 1290 CLEAR_PENDING_EXCEPTION; 1291 { 1292 EXCEPTION_MARK; 1293 add_initialization_error(THREAD, e); 1294 // Locks object, set state, and notify all waiting threads 1295 set_initialization_state_and_notify(initialization_error, THREAD); 1296 CLEAR_PENDING_EXCEPTION; 1297 } 1298 DTRACE_CLASSINIT_PROBE_WAIT(super__failed, -1, wait); 1299 THROW_OOP(e()); 1300 } 1301 } 1302 1303 1304 // Step 8 1305 { 1306 DTRACE_CLASSINIT_PROBE_WAIT(clinit, -1, wait); 1307 if (class_initializer() != nullptr) { 1308 // Timer includes any side effects of class initialization (resolution, 1309 // etc), but not recursive entry into call_class_initializer(). 1310 PerfClassTraceTime timer(ClassLoader::perf_class_init_time(), 1311 ClassLoader::perf_class_init_selftime(), 1312 ClassLoader::perf_classes_inited(), 1313 jt->get_thread_stat()->perf_recursion_counts_addr(), 1314 jt->get_thread_stat()->perf_timers_addr(), 1315 PerfClassTraceTime::CLASS_CLINIT); 1316 call_class_initializer(THREAD); 1317 } else { 1318 // The elapsed time is so small it's not worth counting. 1319 if (UsePerfData) { 1320 ClassLoader::perf_classes_inited()->inc(); 1321 } 1322 call_class_initializer(THREAD); 1323 } 1324 } 1325 1326 // Step 9 1327 if (!HAS_PENDING_EXCEPTION) { 1328 set_initialization_state_and_notify(fully_initialized, CHECK); 1329 DEBUG_ONLY(vtable().verify(tty, true);) 1330 CompilationPolicy::replay_training_at_init(this, THREAD); 1331 } 1332 else { 1333 // Step 10 and 11 1334 Handle e(THREAD, PENDING_EXCEPTION); 1335 CLEAR_PENDING_EXCEPTION; 1336 // JVMTI has already reported the pending exception 1337 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError 1338 JvmtiExport::clear_detected_exception(jt); 1339 { 1340 EXCEPTION_MARK; 1341 add_initialization_error(THREAD, e); 1342 set_initialization_state_and_notify(initialization_error, THREAD); 1343 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, class initialization error is thrown below 1344 // JVMTI has already reported the pending exception 1345 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError 1346 JvmtiExport::clear_detected_exception(jt); 1347 } 1348 DTRACE_CLASSINIT_PROBE_WAIT(error, -1, wait); 1349 if (e->is_a(vmClasses::Error_klass())) { 1350 THROW_OOP(e()); 1351 } else { 1352 JavaCallArguments args(e); 1353 THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(), 1354 vmSymbols::throwable_void_signature(), 1355 &args); 1356 } 1357 } 1358 DTRACE_CLASSINIT_PROBE_WAIT(end, -1, wait); 1359 } 1360 1361 1362 void InstanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) { 1363 Handle h_init_lock(THREAD, init_lock()); 1364 if (h_init_lock() != nullptr) { 1365 ObjectLocker ol(h_init_lock, THREAD); 1366 set_init_thread(nullptr); // reset _init_thread before changing _init_state 1367 set_init_state(state); 1368 fence_and_clear_init_lock(); 1369 ol.notify_all(CHECK); 1370 } else { 1371 assert(h_init_lock() != nullptr, "The initialization state should never be set twice"); 1372 set_init_thread(nullptr); // reset _init_thread before changing _init_state 1373 set_init_state(state); 1374 } 1375 } 1376 1377 // Update hierarchy. This is done before the new klass has been added to the SystemDictionary. The Compile_lock 1378 // is grabbed, to ensure that the compiler is not using the class hierarchy. 1379 void InstanceKlass::add_to_hierarchy(JavaThread* current) { 1380 assert(!SafepointSynchronize::is_at_safepoint(), "must NOT be at safepoint"); 1381 1382 DeoptimizationScope deopt_scope; 1383 { 1384 MutexLocker ml(current, Compile_lock); 1385 1386 set_init_state(InstanceKlass::loaded); 1387 // make sure init_state store is already done. 1388 // The compiler reads the hierarchy outside of the Compile_lock. 1389 // Access ordering is used to add to hierarchy. 1390 1391 // Link into hierarchy. 1392 append_to_sibling_list(); // add to superklass/sibling list 1393 process_interfaces(); // handle all "implements" declarations 1394 1395 // Now mark all code that depended on old class hierarchy. 1396 // Note: must be done *after* linking k into the hierarchy (was bug 12/9/97) 1397 if (Universe::is_fully_initialized()) { 1398 CodeCache::mark_dependents_on(&deopt_scope, this); 1399 } 1400 } 1401 // Perform the deopt handshake outside Compile_lock. 1402 deopt_scope.deoptimize_marked(); 1403 } 1404 1405 1406 InstanceKlass* InstanceKlass::implementor() const { 1407 InstanceKlass* volatile* ik = adr_implementor(); 1408 if (ik == nullptr) { 1409 return nullptr; 1410 } else { 1411 // This load races with inserts, and therefore needs acquire. 1412 InstanceKlass* ikls = Atomic::load_acquire(ik); 1413 if (ikls != nullptr && !ikls->is_loader_alive()) { 1414 return nullptr; // don't return unloaded class 1415 } else { 1416 return ikls; 1417 } 1418 } 1419 } 1420 1421 1422 void InstanceKlass::set_implementor(InstanceKlass* ik) { 1423 assert_locked_or_safepoint(Compile_lock); 1424 assert(is_interface(), "not interface"); 1425 InstanceKlass* volatile* addr = adr_implementor(); 1426 assert(addr != nullptr, "null addr"); 1427 if (addr != nullptr) { 1428 Atomic::release_store(addr, ik); 1429 } 1430 } 1431 1432 int InstanceKlass::nof_implementors() const { 1433 InstanceKlass* ik = implementor(); 1434 if (ik == nullptr) { 1435 return 0; 1436 } else if (ik != this) { 1437 return 1; 1438 } else { 1439 return 2; 1440 } 1441 } 1442 1443 // The embedded _implementor field can only record one implementor. 1444 // When there are more than one implementors, the _implementor field 1445 // is set to the interface Klass* itself. Following are the possible 1446 // values for the _implementor field: 1447 // null - no implementor 1448 // implementor Klass* - one implementor 1449 // self - more than one implementor 1450 // 1451 // The _implementor field only exists for interfaces. 1452 void InstanceKlass::add_implementor(InstanceKlass* ik) { 1453 if (Universe::is_fully_initialized()) { 1454 assert_lock_strong(Compile_lock); 1455 } 1456 assert(is_interface(), "not interface"); 1457 // Filter out my subinterfaces. 1458 // (Note: Interfaces are never on the subklass list.) 1459 if (ik->is_interface()) return; 1460 1461 // Filter out subclasses whose supers already implement me. 1462 // (Note: CHA must walk subclasses of direct implementors 1463 // in order to locate indirect implementors.) 1464 InstanceKlass* super_ik = ik->java_super(); 1465 if (super_ik != nullptr && super_ik->implements_interface(this)) 1466 // We only need to check one immediate superclass, since the 1467 // implements_interface query looks at transitive_interfaces. 1468 // Any supers of the super have the same (or fewer) transitive_interfaces. 1469 return; 1470 1471 InstanceKlass* iklass = implementor(); 1472 if (iklass == nullptr) { 1473 set_implementor(ik); 1474 } else if (iklass != this && iklass != ik) { 1475 // There is already an implementor. Use itself as an indicator of 1476 // more than one implementors. 1477 set_implementor(this); 1478 } 1479 1480 // The implementor also implements the transitive_interfaces 1481 for (int index = 0; index < local_interfaces()->length(); index++) { 1482 local_interfaces()->at(index)->add_implementor(ik); 1483 } 1484 } 1485 1486 void InstanceKlass::init_implementor() { 1487 if (is_interface()) { 1488 set_implementor(nullptr); 1489 } 1490 } 1491 1492 1493 void InstanceKlass::process_interfaces() { 1494 // link this class into the implementors list of every interface it implements 1495 for (int i = local_interfaces()->length() - 1; i >= 0; i--) { 1496 assert(local_interfaces()->at(i)->is_klass(), "must be a klass"); 1497 InstanceKlass* interf = local_interfaces()->at(i); 1498 assert(interf->is_interface(), "expected interface"); 1499 interf->add_implementor(this); 1500 } 1501 } 1502 1503 bool InstanceKlass::can_be_primary_super_slow() const { 1504 if (is_interface()) 1505 return false; 1506 else 1507 return Klass::can_be_primary_super_slow(); 1508 } 1509 1510 GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots, 1511 Array<InstanceKlass*>* transitive_interfaces) { 1512 // The secondaries are the implemented interfaces. 1513 // We need the cast because Array<Klass*> is NOT a supertype of Array<InstanceKlass*>, 1514 // (but it's safe to do here because we won't write into _secondary_supers from this point on). 1515 Array<Klass*>* interfaces = (Array<Klass*>*)(address)transitive_interfaces; 1516 int num_secondaries = num_extra_slots + interfaces->length(); 1517 if (num_secondaries == 0) { 1518 // Must share this for correct bootstrapping! 1519 set_secondary_supers(Universe::the_empty_klass_array(), Universe::the_empty_klass_bitmap()); 1520 return nullptr; 1521 } else if (num_extra_slots == 0 && interfaces->length() <= 1) { 1522 // We will reuse the transitive interfaces list if we're certain 1523 // it's in hash order. 1524 uintx bitmap = compute_secondary_supers_bitmap(interfaces); 1525 set_secondary_supers(interfaces, bitmap); 1526 return nullptr; 1527 } 1528 // Copy transitive interfaces to a temporary growable array to be constructed 1529 // into the secondary super list with extra slots. 1530 GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length()); 1531 for (int i = 0; i < interfaces->length(); i++) { 1532 secondaries->push(interfaces->at(i)); 1533 } 1534 return secondaries; 1535 } 1536 1537 bool InstanceKlass::implements_interface(Klass* k) const { 1538 if (this == k) return true; 1539 assert(k->is_interface(), "should be an interface class"); 1540 for (int i = 0; i < transitive_interfaces()->length(); i++) { 1541 if (transitive_interfaces()->at(i) == k) { 1542 return true; 1543 } 1544 } 1545 return false; 1546 } 1547 1548 bool InstanceKlass::is_same_or_direct_interface(Klass *k) const { 1549 // Verify direct super interface 1550 if (this == k) return true; 1551 assert(k->is_interface(), "should be an interface class"); 1552 for (int i = 0; i < local_interfaces()->length(); i++) { 1553 if (local_interfaces()->at(i) == k) { 1554 return true; 1555 } 1556 } 1557 return false; 1558 } 1559 1560 objArrayOop InstanceKlass::allocate_objArray(int n, int length, TRAPS) { 1561 check_array_allocation_length(length, arrayOopDesc::max_array_length(T_OBJECT), CHECK_NULL); 1562 size_t size = objArrayOopDesc::object_size(length); 1563 ArrayKlass* ak = array_klass(n, CHECK_NULL); 1564 objArrayOop o = (objArrayOop)Universe::heap()->array_allocate(ak, size, length, 1565 /* do_zero */ true, CHECK_NULL); 1566 return o; 1567 } 1568 1569 instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) { 1570 if (TraceFinalizerRegistration) { 1571 tty->print("Registered "); 1572 i->print_value_on(tty); 1573 tty->print_cr(" (" PTR_FORMAT ") as finalizable", p2i(i)); 1574 } 1575 instanceHandle h_i(THREAD, i); 1576 // Pass the handle as argument, JavaCalls::call expects oop as jobjects 1577 JavaValue result(T_VOID); 1578 JavaCallArguments args(h_i); 1579 methodHandle mh(THREAD, Universe::finalizer_register_method()); 1580 JavaCalls::call(&result, mh, &args, CHECK_NULL); 1581 MANAGEMENT_ONLY(FinalizerService::on_register(h_i(), THREAD);) 1582 return h_i(); 1583 } 1584 1585 instanceOop InstanceKlass::allocate_instance(TRAPS) { 1586 assert(!is_abstract() && !is_interface(), "Should not create this object"); 1587 size_t size = size_helper(); // Query before forming handle. 1588 return (instanceOop)Universe::heap()->obj_allocate(this, size, CHECK_NULL); 1589 } 1590 1591 instanceOop InstanceKlass::allocate_instance(oop java_class, TRAPS) { 1592 Klass* k = java_lang_Class::as_Klass(java_class); 1593 if (k == nullptr) { 1594 ResourceMark rm(THREAD); 1595 THROW_(vmSymbols::java_lang_InstantiationException(), nullptr); 1596 } 1597 InstanceKlass* ik = cast(k); 1598 ik->check_valid_for_instantiation(false, CHECK_NULL); 1599 ik->initialize(CHECK_NULL); 1600 return ik->allocate_instance(THREAD); 1601 } 1602 1603 instanceHandle InstanceKlass::allocate_instance_handle(TRAPS) { 1604 return instanceHandle(THREAD, allocate_instance(THREAD)); 1605 } 1606 1607 void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) { 1608 if (is_interface() || is_abstract()) { 1609 ResourceMark rm(THREAD); 1610 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError() 1611 : vmSymbols::java_lang_InstantiationException(), external_name()); 1612 } 1613 if (this == vmClasses::Class_klass()) { 1614 ResourceMark rm(THREAD); 1615 THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError() 1616 : vmSymbols::java_lang_IllegalAccessException(), external_name()); 1617 } 1618 } 1619 1620 ArrayKlass* InstanceKlass::array_klass(int n, TRAPS) { 1621 // Need load-acquire for lock-free read 1622 if (array_klasses_acquire() == nullptr) { 1623 1624 // Recursively lock array allocation 1625 RecursiveLocker rl(MultiArray_lock, THREAD); 1626 1627 // Check if another thread created the array klass while we were waiting for the lock. 1628 if (array_klasses() == nullptr) { 1629 ObjArrayKlass* k = ObjArrayKlass::allocate_objArray_klass(class_loader_data(), 1, this, CHECK_NULL); 1630 // use 'release' to pair with lock-free load 1631 release_set_array_klasses(k); 1632 } 1633 } 1634 1635 // array_klasses() will always be set at this point 1636 ObjArrayKlass* ak = array_klasses(); 1637 assert(ak != nullptr, "should be set"); 1638 return ak->array_klass(n, THREAD); 1639 } 1640 1641 ArrayKlass* InstanceKlass::array_klass_or_null(int n) { 1642 // Need load-acquire for lock-free read 1643 ObjArrayKlass* oak = array_klasses_acquire(); 1644 if (oak == nullptr) { 1645 return nullptr; 1646 } else { 1647 return oak->array_klass_or_null(n); 1648 } 1649 } 1650 1651 ArrayKlass* InstanceKlass::array_klass(TRAPS) { 1652 return array_klass(1, THREAD); 1653 } 1654 1655 ArrayKlass* InstanceKlass::array_klass_or_null() { 1656 return array_klass_or_null(1); 1657 } 1658 1659 static int call_class_initializer_counter = 0; // for debugging 1660 1661 Method* InstanceKlass::class_initializer() const { 1662 Method* clinit = find_method( 1663 vmSymbols::class_initializer_name(), vmSymbols::void_method_signature()); 1664 if (clinit != nullptr && clinit->has_valid_initializer_flags()) { 1665 return clinit; 1666 } 1667 return nullptr; 1668 } 1669 1670 void InstanceKlass::call_class_initializer(TRAPS) { 1671 if (ReplayCompiles && 1672 (ReplaySuppressInitializers == 1 || 1673 (ReplaySuppressInitializers >= 2 && class_loader() != nullptr))) { 1674 // Hide the existence of the initializer for the purpose of replaying the compile 1675 return; 1676 } 1677 1678 #if INCLUDE_CDS 1679 // This is needed to ensure the consistency of the archived heap objects. 1680 if (has_aot_initialized_mirror() && CDSConfig::is_loading_heap()) { 1681 AOTClassInitializer::call_runtime_setup(THREAD, this); 1682 return; 1683 } else if (has_archived_enum_objs()) { 1684 assert(is_shared(), "must be"); 1685 bool initialized = CDSEnumKlass::initialize_enum_klass(this, CHECK); 1686 if (initialized) { 1687 return; 1688 } 1689 } 1690 #endif 1691 1692 methodHandle h_method(THREAD, class_initializer()); 1693 assert(!is_initialized(), "we cannot initialize twice"); 1694 LogTarget(Info, class, init) lt; 1695 if (lt.is_enabled()) { 1696 ResourceMark rm(THREAD); 1697 LogStream ls(lt); 1698 ls.print("%d Initializing ", call_class_initializer_counter++); 1699 name()->print_value_on(&ls); 1700 ls.print_cr("%s (" PTR_FORMAT ") by thread \"%s\"", 1701 h_method() == nullptr ? "(no method)" : "", p2i(this), 1702 THREAD->name()); 1703 } 1704 if (h_method() != nullptr) { 1705 ThreadInClassInitializer ticl(THREAD, this); // Track class being initialized 1706 JavaCallArguments args; // No arguments 1707 JavaValue result(T_VOID); 1708 JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args) 1709 } 1710 } 1711 1712 // If a class that implements this interface is initialized, is the JVM required 1713 // to first execute a <clinit> method declared in this interface, 1714 // or (if also_check_supers==true) any of the super types of this interface? 1715 // 1716 // JVMS 5.5. Initialization, step 7: Next, if C is a class rather than 1717 // an interface, then let SC be its superclass and let SI1, ..., SIn 1718 // be all superinterfaces of C (whether direct or indirect) that 1719 // declare at least one non-abstract, non-static method. 1720 // 1721 // So when an interface is initialized, it does not look at its 1722 // supers. But a proper class will ensure that all of its supers have 1723 // run their <clinit> methods, except that it disregards interfaces 1724 // that lack a non-static concrete method (i.e., a default method). 1725 // Therefore, you should probably call this method only when the 1726 // current class is a super of some proper class, not an interface. 1727 bool InstanceKlass::interface_needs_clinit_execution_as_super(bool also_check_supers) const { 1728 assert(is_interface(), "must be"); 1729 1730 if (!has_nonstatic_concrete_methods()) { 1731 // quick check: no nonstatic concrete methods are declared by this or any super interfaces 1732 return false; 1733 } 1734 1735 // JVMS 5.5. Initialization 1736 // ...If C is an interface that declares a non-abstract, 1737 // non-static method, the initialization of a class that 1738 // implements C directly or indirectly. 1739 if (declares_nonstatic_concrete_methods() && class_initializer() != nullptr) { 1740 return true; 1741 } 1742 if (also_check_supers) { 1743 Array<InstanceKlass*>* all_ifs = transitive_interfaces(); 1744 for (int i = 0; i < all_ifs->length(); ++i) { 1745 InstanceKlass* super_intf = all_ifs->at(i); 1746 if (super_intf->declares_nonstatic_concrete_methods() && super_intf->class_initializer() != nullptr) { 1747 return true; 1748 } 1749 } 1750 } 1751 return false; 1752 } 1753 1754 void InstanceKlass::mask_for(const methodHandle& method, int bci, 1755 InterpreterOopMap* entry_for) { 1756 // Lazily create the _oop_map_cache at first request. 1757 // Load_acquire is needed to safely get instance published with CAS by another thread. 1758 OopMapCache* oop_map_cache = Atomic::load_acquire(&_oop_map_cache); 1759 if (oop_map_cache == nullptr) { 1760 // Try to install new instance atomically. 1761 oop_map_cache = new OopMapCache(); 1762 OopMapCache* other = Atomic::cmpxchg(&_oop_map_cache, (OopMapCache*)nullptr, oop_map_cache); 1763 if (other != nullptr) { 1764 // Someone else managed to install before us, ditch local copy and use the existing one. 1765 delete oop_map_cache; 1766 oop_map_cache = other; 1767 } 1768 } 1769 // _oop_map_cache is constant after init; lookup below does its own locking. 1770 oop_map_cache->lookup(method, bci, entry_for); 1771 } 1772 1773 bool InstanceKlass::contains_field_offset(int offset) { 1774 fieldDescriptor fd; 1775 return find_field_from_offset(offset, false, &fd); 1776 } 1777 1778 FieldInfo InstanceKlass::field(int index) const { 1779 for (AllFieldStream fs(this); !fs.done(); fs.next()) { 1780 if (fs.index() == index) { 1781 return fs.to_FieldInfo(); 1782 } 1783 } 1784 fatal("Field not found"); 1785 return FieldInfo(); 1786 } 1787 1788 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const { 1789 for (JavaFieldStream fs(this); !fs.done(); fs.next()) { 1790 Symbol* f_name = fs.name(); 1791 Symbol* f_sig = fs.signature(); 1792 if (f_name == name && f_sig == sig) { 1793 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.to_FieldInfo()); 1794 return true; 1795 } 1796 } 1797 return false; 1798 } 1799 1800 1801 Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const { 1802 const int n = local_interfaces()->length(); 1803 for (int i = 0; i < n; i++) { 1804 Klass* intf1 = local_interfaces()->at(i); 1805 assert(intf1->is_interface(), "just checking type"); 1806 // search for field in current interface 1807 if (InstanceKlass::cast(intf1)->find_local_field(name, sig, fd)) { 1808 assert(fd->is_static(), "interface field must be static"); 1809 return intf1; 1810 } 1811 // search for field in direct superinterfaces 1812 Klass* intf2 = InstanceKlass::cast(intf1)->find_interface_field(name, sig, fd); 1813 if (intf2 != nullptr) return intf2; 1814 } 1815 // otherwise field lookup fails 1816 return nullptr; 1817 } 1818 1819 1820 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const { 1821 // search order according to newest JVM spec (5.4.3.2, p.167). 1822 // 1) search for field in current klass 1823 if (find_local_field(name, sig, fd)) { 1824 return const_cast<InstanceKlass*>(this); 1825 } 1826 // 2) search for field recursively in direct superinterfaces 1827 { Klass* intf = find_interface_field(name, sig, fd); 1828 if (intf != nullptr) return intf; 1829 } 1830 // 3) apply field lookup recursively if superclass exists 1831 { Klass* supr = super(); 1832 if (supr != nullptr) return InstanceKlass::cast(supr)->find_field(name, sig, fd); 1833 } 1834 // 4) otherwise field lookup fails 1835 return nullptr; 1836 } 1837 1838 1839 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const { 1840 // search order according to newest JVM spec (5.4.3.2, p.167). 1841 // 1) search for field in current klass 1842 if (find_local_field(name, sig, fd)) { 1843 if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this); 1844 } 1845 // 2) search for field recursively in direct superinterfaces 1846 if (is_static) { 1847 Klass* intf = find_interface_field(name, sig, fd); 1848 if (intf != nullptr) return intf; 1849 } 1850 // 3) apply field lookup recursively if superclass exists 1851 { Klass* supr = super(); 1852 if (supr != nullptr) return InstanceKlass::cast(supr)->find_field(name, sig, is_static, fd); 1853 } 1854 // 4) otherwise field lookup fails 1855 return nullptr; 1856 } 1857 1858 1859 bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const { 1860 for (JavaFieldStream fs(this); !fs.done(); fs.next()) { 1861 if (fs.offset() == offset) { 1862 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.to_FieldInfo()); 1863 if (fd->is_static() == is_static) return true; 1864 } 1865 } 1866 return false; 1867 } 1868 1869 1870 bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const { 1871 Klass* klass = const_cast<InstanceKlass*>(this); 1872 while (klass != nullptr) { 1873 if (InstanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) { 1874 return true; 1875 } 1876 klass = klass->super(); 1877 } 1878 return false; 1879 } 1880 1881 1882 void InstanceKlass::methods_do(void f(Method* method)) { 1883 // Methods aren't stable until they are loaded. This can be read outside 1884 // a lock through the ClassLoaderData for profiling 1885 // Redefined scratch classes are on the list and need to be cleaned 1886 if (!is_loaded() && !is_scratch_class()) { 1887 return; 1888 } 1889 1890 int len = methods()->length(); 1891 for (int index = 0; index < len; index++) { 1892 Method* m = methods()->at(index); 1893 assert(m->is_method(), "must be method"); 1894 f(m); 1895 } 1896 } 1897 1898 1899 void InstanceKlass::do_local_static_fields(FieldClosure* cl) { 1900 for (JavaFieldStream fs(this); !fs.done(); fs.next()) { 1901 if (fs.access_flags().is_static()) { 1902 fieldDescriptor& fd = fs.field_descriptor(); 1903 cl->do_field(&fd); 1904 } 1905 } 1906 } 1907 1908 1909 void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle mirror, TRAPS) { 1910 for (JavaFieldStream fs(this); !fs.done(); fs.next()) { 1911 if (fs.access_flags().is_static()) { 1912 fieldDescriptor& fd = fs.field_descriptor(); 1913 f(&fd, mirror, CHECK); 1914 } 1915 } 1916 } 1917 1918 void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) { 1919 InstanceKlass* super = superklass(); 1920 if (super != nullptr) { 1921 super->do_nonstatic_fields(cl); 1922 } 1923 for (JavaFieldStream fs(this); !fs.done(); fs.next()) { 1924 fieldDescriptor& fd = fs.field_descriptor(); 1925 if (!fd.is_static()) { 1926 cl->do_field(&fd); 1927 } 1928 } 1929 } 1930 1931 static int compare_fields_by_offset(FieldInfo* a, FieldInfo* b) { 1932 return a->offset() - b->offset(); 1933 } 1934 1935 void InstanceKlass::print_nonstatic_fields(FieldClosure* cl) { 1936 InstanceKlass* super = superklass(); 1937 if (super != nullptr) { 1938 super->print_nonstatic_fields(cl); 1939 } 1940 ResourceMark rm; 1941 // In DebugInfo nonstatic fields are sorted by offset. 1942 GrowableArray<FieldInfo> fields_sorted; 1943 for (AllFieldStream fs(this); !fs.done(); fs.next()) { 1944 if (!fs.access_flags().is_static()) { 1945 fields_sorted.push(fs.to_FieldInfo()); 1946 } 1947 } 1948 int length = fields_sorted.length(); 1949 if (length > 0) { 1950 fields_sorted.sort(compare_fields_by_offset); 1951 fieldDescriptor fd; 1952 for (int i = 0; i < length; i++) { 1953 fd.reinitialize(this, fields_sorted.at(i)); 1954 assert(!fd.is_static() && fd.offset() == checked_cast<int>(fields_sorted.at(i).offset()), "only nonstatic fields"); 1955 cl->do_field(&fd); 1956 } 1957 } 1958 } 1959 1960 #ifdef ASSERT 1961 static int linear_search(const Array<Method*>* methods, 1962 const Symbol* name, 1963 const Symbol* signature) { 1964 const int len = methods->length(); 1965 for (int index = 0; index < len; index++) { 1966 const Method* const m = methods->at(index); 1967 assert(m->is_method(), "must be method"); 1968 if (m->signature() == signature && m->name() == name) { 1969 return index; 1970 } 1971 } 1972 return -1; 1973 } 1974 #endif 1975 1976 bool InstanceKlass::_disable_method_binary_search = false; 1977 1978 NOINLINE int linear_search(const Array<Method*>* methods, const Symbol* name) { 1979 int len = methods->length(); 1980 int l = 0; 1981 int h = len - 1; 1982 while (l <= h) { 1983 Method* m = methods->at(l); 1984 if (m->name() == name) { 1985 return l; 1986 } 1987 l++; 1988 } 1989 return -1; 1990 } 1991 1992 inline int InstanceKlass::quick_search(const Array<Method*>* methods, const Symbol* name) { 1993 if (_disable_method_binary_search) { 1994 assert(CDSConfig::is_dumping_dynamic_archive(), "must be"); 1995 // At the final stage of dynamic dumping, the methods array may not be sorted 1996 // by ascending addresses of their names, so we can't use binary search anymore. 1997 // However, methods with the same name are still laid out consecutively inside the 1998 // methods array, so let's look for the first one that matches. 1999 return linear_search(methods, name); 2000 } 2001 2002 int len = methods->length(); 2003 int l = 0; 2004 int h = len - 1; 2005 2006 // methods are sorted by ascending addresses of their names, so do binary search 2007 while (l <= h) { 2008 int mid = (l + h) >> 1; 2009 Method* m = methods->at(mid); 2010 assert(m->is_method(), "must be method"); 2011 int res = m->name()->fast_compare(name); 2012 if (res == 0) { 2013 return mid; 2014 } else if (res < 0) { 2015 l = mid + 1; 2016 } else { 2017 h = mid - 1; 2018 } 2019 } 2020 return -1; 2021 } 2022 2023 // find_method looks up the name/signature in the local methods array 2024 Method* InstanceKlass::find_method(const Symbol* name, 2025 const Symbol* signature) const { 2026 return find_method_impl(name, signature, 2027 OverpassLookupMode::find, 2028 StaticLookupMode::find, 2029 PrivateLookupMode::find); 2030 } 2031 2032 Method* InstanceKlass::find_method_impl(const Symbol* name, 2033 const Symbol* signature, 2034 OverpassLookupMode overpass_mode, 2035 StaticLookupMode static_mode, 2036 PrivateLookupMode private_mode) const { 2037 return InstanceKlass::find_method_impl(methods(), 2038 name, 2039 signature, 2040 overpass_mode, 2041 static_mode, 2042 private_mode); 2043 } 2044 2045 // find_instance_method looks up the name/signature in the local methods array 2046 // and skips over static methods 2047 Method* InstanceKlass::find_instance_method(const Array<Method*>* methods, 2048 const Symbol* name, 2049 const Symbol* signature, 2050 PrivateLookupMode private_mode) { 2051 Method* const meth = InstanceKlass::find_method_impl(methods, 2052 name, 2053 signature, 2054 OverpassLookupMode::find, 2055 StaticLookupMode::skip, 2056 private_mode); 2057 assert(((meth == nullptr) || !meth->is_static()), 2058 "find_instance_method should have skipped statics"); 2059 return meth; 2060 } 2061 2062 // find_instance_method looks up the name/signature in the local methods array 2063 // and skips over static methods 2064 Method* InstanceKlass::find_instance_method(const Symbol* name, 2065 const Symbol* signature, 2066 PrivateLookupMode private_mode) const { 2067 return InstanceKlass::find_instance_method(methods(), name, signature, private_mode); 2068 } 2069 2070 // Find looks up the name/signature in the local methods array 2071 // and filters on the overpass, static and private flags 2072 // This returns the first one found 2073 // note that the local methods array can have up to one overpass, one static 2074 // and one instance (private or not) with the same name/signature 2075 Method* InstanceKlass::find_local_method(const Symbol* name, 2076 const Symbol* signature, 2077 OverpassLookupMode overpass_mode, 2078 StaticLookupMode static_mode, 2079 PrivateLookupMode private_mode) const { 2080 return InstanceKlass::find_method_impl(methods(), 2081 name, 2082 signature, 2083 overpass_mode, 2084 static_mode, 2085 private_mode); 2086 } 2087 2088 // Find looks up the name/signature in the local methods array 2089 // and filters on the overpass, static and private flags 2090 // This returns the first one found 2091 // note that the local methods array can have up to one overpass, one static 2092 // and one instance (private or not) with the same name/signature 2093 Method* InstanceKlass::find_local_method(const Array<Method*>* methods, 2094 const Symbol* name, 2095 const Symbol* signature, 2096 OverpassLookupMode overpass_mode, 2097 StaticLookupMode static_mode, 2098 PrivateLookupMode private_mode) { 2099 return InstanceKlass::find_method_impl(methods, 2100 name, 2101 signature, 2102 overpass_mode, 2103 static_mode, 2104 private_mode); 2105 } 2106 2107 Method* InstanceKlass::find_method(const Array<Method*>* methods, 2108 const Symbol* name, 2109 const Symbol* signature) { 2110 return InstanceKlass::find_method_impl(methods, 2111 name, 2112 signature, 2113 OverpassLookupMode::find, 2114 StaticLookupMode::find, 2115 PrivateLookupMode::find); 2116 } 2117 2118 Method* InstanceKlass::find_method_impl(const Array<Method*>* methods, 2119 const Symbol* name, 2120 const Symbol* signature, 2121 OverpassLookupMode overpass_mode, 2122 StaticLookupMode static_mode, 2123 PrivateLookupMode private_mode) { 2124 int hit = find_method_index(methods, name, signature, overpass_mode, static_mode, private_mode); 2125 return hit >= 0 ? methods->at(hit): nullptr; 2126 } 2127 2128 // true if method matches signature and conforms to skipping_X conditions. 2129 static bool method_matches(const Method* m, 2130 const Symbol* signature, 2131 bool skipping_overpass, 2132 bool skipping_static, 2133 bool skipping_private) { 2134 return ((m->signature() == signature) && 2135 (!skipping_overpass || !m->is_overpass()) && 2136 (!skipping_static || !m->is_static()) && 2137 (!skipping_private || !m->is_private())); 2138 } 2139 2140 // Used directly for default_methods to find the index into the 2141 // default_vtable_indices, and indirectly by find_method 2142 // find_method_index looks in the local methods array to return the index 2143 // of the matching name/signature. If, overpass methods are being ignored, 2144 // the search continues to find a potential non-overpass match. This capability 2145 // is important during method resolution to prefer a static method, for example, 2146 // over an overpass method. 2147 // There is the possibility in any _method's array to have the same name/signature 2148 // for a static method, an overpass method and a local instance method 2149 // To correctly catch a given method, the search criteria may need 2150 // to explicitly skip the other two. For local instance methods, it 2151 // is often necessary to skip private methods 2152 int InstanceKlass::find_method_index(const Array<Method*>* methods, 2153 const Symbol* name, 2154 const Symbol* signature, 2155 OverpassLookupMode overpass_mode, 2156 StaticLookupMode static_mode, 2157 PrivateLookupMode private_mode) { 2158 const bool skipping_overpass = (overpass_mode == OverpassLookupMode::skip); 2159 const bool skipping_static = (static_mode == StaticLookupMode::skip); 2160 const bool skipping_private = (private_mode == PrivateLookupMode::skip); 2161 const int hit = quick_search(methods, name); 2162 if (hit != -1) { 2163 const Method* const m = methods->at(hit); 2164 2165 // Do linear search to find matching signature. First, quick check 2166 // for common case, ignoring overpasses if requested. 2167 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) { 2168 return hit; 2169 } 2170 2171 // search downwards through overloaded methods 2172 int i; 2173 for (i = hit - 1; i >= 0; --i) { 2174 const Method* const m = methods->at(i); 2175 assert(m->is_method(), "must be method"); 2176 if (m->name() != name) { 2177 break; 2178 } 2179 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) { 2180 return i; 2181 } 2182 } 2183 // search upwards 2184 for (i = hit + 1; i < methods->length(); ++i) { 2185 const Method* const m = methods->at(i); 2186 assert(m->is_method(), "must be method"); 2187 if (m->name() != name) { 2188 break; 2189 } 2190 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) { 2191 return i; 2192 } 2193 } 2194 // not found 2195 #ifdef ASSERT 2196 const int index = (skipping_overpass || skipping_static || skipping_private) ? -1 : 2197 linear_search(methods, name, signature); 2198 assert(-1 == index, "binary search should have found entry %d", index); 2199 #endif 2200 } 2201 return -1; 2202 } 2203 2204 int InstanceKlass::find_method_by_name(const Symbol* name, int* end) const { 2205 return find_method_by_name(methods(), name, end); 2206 } 2207 2208 int InstanceKlass::find_method_by_name(const Array<Method*>* methods, 2209 const Symbol* name, 2210 int* end_ptr) { 2211 assert(end_ptr != nullptr, "just checking"); 2212 int start = quick_search(methods, name); 2213 int end = start + 1; 2214 if (start != -1) { 2215 while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start; 2216 while (end < methods->length() && (methods->at(end))->name() == name) ++end; 2217 *end_ptr = end; 2218 return start; 2219 } 2220 return -1; 2221 } 2222 2223 // uncached_lookup_method searches both the local class methods array and all 2224 // superclasses methods arrays, skipping any overpass methods in superclasses, 2225 // and possibly skipping private methods. 2226 Method* InstanceKlass::uncached_lookup_method(const Symbol* name, 2227 const Symbol* signature, 2228 OverpassLookupMode overpass_mode, 2229 PrivateLookupMode private_mode) const { 2230 OverpassLookupMode overpass_local_mode = overpass_mode; 2231 const Klass* klass = this; 2232 while (klass != nullptr) { 2233 Method* const method = InstanceKlass::cast(klass)->find_method_impl(name, 2234 signature, 2235 overpass_local_mode, 2236 StaticLookupMode::find, 2237 private_mode); 2238 if (method != nullptr) { 2239 return method; 2240 } 2241 klass = klass->super(); 2242 overpass_local_mode = OverpassLookupMode::skip; // Always ignore overpass methods in superclasses 2243 } 2244 return nullptr; 2245 } 2246 2247 #ifdef ASSERT 2248 // search through class hierarchy and return true if this class or 2249 // one of the superclasses was redefined 2250 bool InstanceKlass::has_redefined_this_or_super() const { 2251 const Klass* klass = this; 2252 while (klass != nullptr) { 2253 if (InstanceKlass::cast(klass)->has_been_redefined()) { 2254 return true; 2255 } 2256 klass = klass->super(); 2257 } 2258 return false; 2259 } 2260 #endif 2261 2262 // lookup a method in the default methods list then in all transitive interfaces 2263 // Do NOT return private or static methods 2264 Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name, 2265 Symbol* signature) const { 2266 Method* m = nullptr; 2267 if (default_methods() != nullptr) { 2268 m = find_method(default_methods(), name, signature); 2269 } 2270 // Look up interfaces 2271 if (m == nullptr) { 2272 m = lookup_method_in_all_interfaces(name, signature, DefaultsLookupMode::find); 2273 } 2274 return m; 2275 } 2276 2277 // lookup a method in all the interfaces that this class implements 2278 // Do NOT return private or static methods, new in JDK8 which are not externally visible 2279 // They should only be found in the initial InterfaceMethodRef 2280 Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name, 2281 Symbol* signature, 2282 DefaultsLookupMode defaults_mode) const { 2283 Array<InstanceKlass*>* all_ifs = transitive_interfaces(); 2284 int num_ifs = all_ifs->length(); 2285 InstanceKlass *ik = nullptr; 2286 for (int i = 0; i < num_ifs; i++) { 2287 ik = all_ifs->at(i); 2288 Method* m = ik->lookup_method(name, signature); 2289 if (m != nullptr && m->is_public() && !m->is_static() && 2290 ((defaults_mode != DefaultsLookupMode::skip) || !m->is_default_method())) { 2291 return m; 2292 } 2293 } 2294 return nullptr; 2295 } 2296 2297 PrintClassClosure::PrintClassClosure(outputStream* st, bool verbose) 2298 :_st(st), _verbose(verbose) { 2299 ResourceMark rm; 2300 _st->print("%-18s ", "KlassAddr"); 2301 _st->print("%-4s ", "Size"); 2302 _st->print("%-20s ", "State"); 2303 _st->print("%-7s ", "Flags"); 2304 _st->print("%-5s ", "ClassName"); 2305 _st->cr(); 2306 } 2307 2308 void PrintClassClosure::do_klass(Klass* k) { 2309 ResourceMark rm; 2310 // klass pointer 2311 _st->print(PTR_FORMAT " ", p2i(k)); 2312 // klass size 2313 _st->print("%4d ", k->size()); 2314 // initialization state 2315 if (k->is_instance_klass()) { 2316 _st->print("%-20s ",InstanceKlass::cast(k)->init_state_name()); 2317 } else { 2318 _st->print("%-20s ",""); 2319 } 2320 // misc flags(Changes should synced with ClassesDCmd::ClassesDCmd help doc) 2321 char buf[10]; 2322 int i = 0; 2323 if (k->has_finalizer()) buf[i++] = 'F'; 2324 if (k->is_instance_klass()) { 2325 InstanceKlass* ik = InstanceKlass::cast(k); 2326 if (ik->has_final_method()) buf[i++] = 'f'; 2327 if (ik->is_rewritten()) buf[i++] = 'W'; 2328 if (ik->is_contended()) buf[i++] = 'C'; 2329 if (ik->has_been_redefined()) buf[i++] = 'R'; 2330 if (ik->is_shared()) buf[i++] = 'S'; 2331 } 2332 buf[i++] = '\0'; 2333 _st->print("%-7s ", buf); 2334 // klass name 2335 _st->print("%-5s ", k->external_name()); 2336 // end 2337 _st->cr(); 2338 if (_verbose) { 2339 k->print_on(_st); 2340 } 2341 } 2342 2343 /* jni_id_for for jfieldIds only */ 2344 JNIid* InstanceKlass::jni_id_for(int offset) { 2345 MutexLocker ml(JfieldIdCreation_lock); 2346 JNIid* probe = jni_ids() == nullptr ? nullptr : jni_ids()->find(offset); 2347 if (probe == nullptr) { 2348 // Allocate new static field identifier 2349 probe = new JNIid(this, offset, jni_ids()); 2350 set_jni_ids(probe); 2351 } 2352 return probe; 2353 } 2354 2355 u2 InstanceKlass::enclosing_method_data(int offset) const { 2356 const Array<jushort>* const inner_class_list = inner_classes(); 2357 if (inner_class_list == nullptr) { 2358 return 0; 2359 } 2360 const int length = inner_class_list->length(); 2361 if (length % inner_class_next_offset == 0) { 2362 return 0; 2363 } 2364 const int index = length - enclosing_method_attribute_size; 2365 assert(offset < enclosing_method_attribute_size, "invalid offset"); 2366 return inner_class_list->at(index + offset); 2367 } 2368 2369 void InstanceKlass::set_enclosing_method_indices(u2 class_index, 2370 u2 method_index) { 2371 Array<jushort>* inner_class_list = inner_classes(); 2372 assert (inner_class_list != nullptr, "_inner_classes list is not set up"); 2373 int length = inner_class_list->length(); 2374 if (length % inner_class_next_offset == enclosing_method_attribute_size) { 2375 int index = length - enclosing_method_attribute_size; 2376 inner_class_list->at_put( 2377 index + enclosing_method_class_index_offset, class_index); 2378 inner_class_list->at_put( 2379 index + enclosing_method_method_index_offset, method_index); 2380 } 2381 } 2382 2383 jmethodID InstanceKlass::update_jmethod_id(jmethodID* jmeths, Method* method, int idnum) { 2384 if (method->is_old() && !method->is_obsolete()) { 2385 // If the method passed in is old (but not obsolete), use the current version. 2386 method = method_with_idnum((int)idnum); 2387 assert(method != nullptr, "old and but not obsolete, so should exist"); 2388 } 2389 jmethodID new_id = Method::make_jmethod_id(class_loader_data(), method); 2390 Atomic::release_store(&jmeths[idnum + 1], new_id); 2391 return new_id; 2392 } 2393 2394 // Lookup or create a jmethodID. 2395 // This code is called by the VMThread and JavaThreads so the 2396 // locking has to be done very carefully to avoid deadlocks 2397 // and/or other cache consistency problems. 2398 // 2399 jmethodID InstanceKlass::get_jmethod_id(const methodHandle& method_h) { 2400 Method* method = method_h(); 2401 int idnum = method->method_idnum(); 2402 jmethodID* jmeths = methods_jmethod_ids_acquire(); 2403 2404 // We use a double-check locking idiom here because this cache is 2405 // performance sensitive. In the normal system, this cache only 2406 // transitions from null to non-null which is safe because we use 2407 // release_set_methods_jmethod_ids() to advertise the new cache. 2408 // A partially constructed cache should never be seen by a racing 2409 // thread. We also use release_store() to save a new jmethodID 2410 // in the cache so a partially constructed jmethodID should never be 2411 // seen either. Cache reads of existing jmethodIDs proceed without a 2412 // lock, but cache writes of a new jmethodID requires uniqueness and 2413 // creation of the cache itself requires no leaks so a lock is 2414 // acquired in those two cases. 2415 // 2416 // If the RedefineClasses() API has been used, then this cache grows 2417 // in the redefinition safepoint. 2418 2419 if (jmeths == nullptr) { 2420 MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag); 2421 jmeths = methods_jmethod_ids_acquire(); 2422 // Still null? 2423 if (jmeths == nullptr) { 2424 size_t size = idnum_allocated_count(); 2425 assert(size > (size_t)idnum, "should already have space"); 2426 jmeths = NEW_C_HEAP_ARRAY(jmethodID, size + 1, mtClass); 2427 memset(jmeths, 0, (size + 1) * sizeof(jmethodID)); 2428 // cache size is stored in element[0], other elements offset by one 2429 jmeths[0] = (jmethodID)size; 2430 jmethodID new_id = update_jmethod_id(jmeths, method, idnum); 2431 2432 // publish jmeths 2433 release_set_methods_jmethod_ids(jmeths); 2434 return new_id; 2435 } 2436 } 2437 2438 jmethodID id = Atomic::load_acquire(&jmeths[idnum + 1]); 2439 if (id == nullptr) { 2440 MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag); 2441 id = jmeths[idnum + 1]; 2442 // Still null? 2443 if (id == nullptr) { 2444 return update_jmethod_id(jmeths, method, idnum); 2445 } 2446 } 2447 return id; 2448 } 2449 2450 void InstanceKlass::update_methods_jmethod_cache() { 2451 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint"); 2452 jmethodID* cache = _methods_jmethod_ids; 2453 if (cache != nullptr) { 2454 size_t size = idnum_allocated_count(); 2455 size_t old_size = (size_t)cache[0]; 2456 if (old_size < size + 1) { 2457 // Allocate a larger one and copy entries to the new one. 2458 // They've already been updated to point to new methods where applicable (i.e., not obsolete). 2459 jmethodID* new_cache = NEW_C_HEAP_ARRAY(jmethodID, size + 1, mtClass); 2460 memset(new_cache, 0, (size + 1) * sizeof(jmethodID)); 2461 // The cache size is stored in element[0]; the other elements are offset by one. 2462 new_cache[0] = (jmethodID)size; 2463 2464 for (int i = 1; i <= (int)old_size; i++) { 2465 new_cache[i] = cache[i]; 2466 } 2467 _methods_jmethod_ids = new_cache; 2468 FREE_C_HEAP_ARRAY(jmethodID, cache); 2469 } 2470 } 2471 } 2472 2473 // Figure out how many jmethodIDs haven't been allocated, and make 2474 // sure space for them is pre-allocated. This makes getting all 2475 // method ids much, much faster with classes with more than 8 2476 // methods, and has a *substantial* effect on performance with jvmti 2477 // code that loads all jmethodIDs for all classes. 2478 void InstanceKlass::ensure_space_for_methodids(int start_offset) { 2479 int new_jmeths = 0; 2480 int length = methods()->length(); 2481 for (int index = start_offset; index < length; index++) { 2482 Method* m = methods()->at(index); 2483 jmethodID id = m->find_jmethod_id_or_null(); 2484 if (id == nullptr) { 2485 new_jmeths++; 2486 } 2487 } 2488 if (new_jmeths != 0) { 2489 Method::ensure_jmethod_ids(class_loader_data(), new_jmeths); 2490 } 2491 } 2492 2493 // Lookup a jmethodID, null if not found. Do no blocking, no allocations, no handles 2494 jmethodID InstanceKlass::jmethod_id_or_null(Method* method) { 2495 int idnum = method->method_idnum(); 2496 jmethodID* jmeths = methods_jmethod_ids_acquire(); 2497 return (jmeths != nullptr) ? jmeths[idnum + 1] : nullptr; 2498 } 2499 2500 inline DependencyContext InstanceKlass::dependencies() { 2501 DependencyContext dep_context(&_dep_context, &_dep_context_last_cleaned); 2502 return dep_context; 2503 } 2504 2505 void InstanceKlass::mark_dependent_nmethods(DeoptimizationScope* deopt_scope, KlassDepChange& changes) { 2506 dependencies().mark_dependent_nmethods(deopt_scope, changes); 2507 } 2508 2509 void InstanceKlass::add_dependent_nmethod(nmethod* nm) { 2510 assert_lock_strong(CodeCache_lock); 2511 dependencies().add_dependent_nmethod(nm); 2512 } 2513 2514 void InstanceKlass::clean_dependency_context() { 2515 dependencies().clean_unloading_dependents(); 2516 } 2517 2518 #ifndef PRODUCT 2519 void InstanceKlass::print_dependent_nmethods(bool verbose) { 2520 dependencies().print_dependent_nmethods(verbose); 2521 } 2522 2523 bool InstanceKlass::is_dependent_nmethod(nmethod* nm) { 2524 return dependencies().is_dependent_nmethod(nm); 2525 } 2526 #endif //PRODUCT 2527 2528 void InstanceKlass::clean_weak_instanceklass_links() { 2529 clean_implementors_list(); 2530 clean_method_data(); 2531 } 2532 2533 void InstanceKlass::clean_implementors_list() { 2534 assert(is_loader_alive(), "this klass should be live"); 2535 if (is_interface()) { 2536 assert (ClassUnloading, "only called for ClassUnloading"); 2537 for (;;) { 2538 // Use load_acquire due to competing with inserts 2539 InstanceKlass* volatile* iklass = adr_implementor(); 2540 assert(iklass != nullptr, "Klass must not be null"); 2541 InstanceKlass* impl = Atomic::load_acquire(iklass); 2542 if (impl != nullptr && !impl->is_loader_alive()) { 2543 // null this field, might be an unloaded instance klass or null 2544 if (Atomic::cmpxchg(iklass, impl, (InstanceKlass*)nullptr) == impl) { 2545 // Successfully unlinking implementor. 2546 if (log_is_enabled(Trace, class, unload)) { 2547 ResourceMark rm; 2548 log_trace(class, unload)("unlinking class (implementor): %s", impl->external_name()); 2549 } 2550 return; 2551 } 2552 } else { 2553 return; 2554 } 2555 } 2556 } 2557 } 2558 2559 void InstanceKlass::clean_method_data() { 2560 for (int m = 0; m < methods()->length(); m++) { 2561 MethodData* mdo = methods()->at(m)->method_data(); 2562 if (mdo != nullptr) { 2563 mdo->clean_method_data(/*always_clean*/false); 2564 } 2565 } 2566 } 2567 2568 void InstanceKlass::metaspace_pointers_do(MetaspaceClosure* it) { 2569 Klass::metaspace_pointers_do(it); 2570 2571 if (log_is_enabled(Trace, aot)) { 2572 ResourceMark rm; 2573 log_trace(aot)("Iter(InstanceKlass): %p (%s)", this, external_name()); 2574 } 2575 2576 it->push(&_annotations); 2577 it->push((Klass**)&_array_klasses); 2578 if (!is_rewritten()) { 2579 it->push(&_constants, MetaspaceClosure::_writable); 2580 } else { 2581 it->push(&_constants); 2582 } 2583 it->push(&_inner_classes); 2584 #if INCLUDE_JVMTI 2585 it->push(&_previous_versions); 2586 #endif 2587 #if INCLUDE_CDS 2588 // For "old" classes with methods containing the jsr bytecode, the _methods array will 2589 // be rewritten during runtime (see Rewriter::rewrite_jsrs()) but they cannot be safely 2590 // checked here with ByteCodeStream. All methods that can't be verified are made writable. 2591 // The length check on the _methods is necessary because classes which don't have any 2592 // methods share the Universe::_the_empty_method_array which is in the RO region. 2593 if (_methods != nullptr && _methods->length() > 0 && !can_be_verified_at_dumptime()) { 2594 // To handle jsr bytecode, new Method* maybe stored into _methods 2595 it->push(&_methods, MetaspaceClosure::_writable); 2596 } else { 2597 #endif 2598 it->push(&_methods); 2599 #if INCLUDE_CDS 2600 } 2601 #endif 2602 it->push(&_default_methods); 2603 it->push(&_local_interfaces); 2604 it->push(&_transitive_interfaces); 2605 it->push(&_method_ordering); 2606 if (!is_rewritten()) { 2607 it->push(&_default_vtable_indices, MetaspaceClosure::_writable); 2608 } else { 2609 it->push(&_default_vtable_indices); 2610 } 2611 2612 it->push(&_fieldinfo_stream); 2613 // _fields_status might be written into by Rewriter::scan_method() -> fd.set_has_initialized_final_update() 2614 it->push(&_fields_status, MetaspaceClosure::_writable); 2615 2616 if (itable_length() > 0) { 2617 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable(); 2618 int method_table_offset_in_words = ioe->offset()/wordSize; 2619 int itable_offset_in_words = (int)(start_of_itable() - (intptr_t*)this); 2620 2621 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words) 2622 / itableOffsetEntry::size(); 2623 2624 for (int i = 0; i < nof_interfaces; i ++, ioe ++) { 2625 if (ioe->interface_klass() != nullptr) { 2626 it->push(ioe->interface_klass_addr()); 2627 itableMethodEntry* ime = ioe->first_method_entry(this); 2628 int n = klassItable::method_count_for_interface(ioe->interface_klass()); 2629 for (int index = 0; index < n; index ++) { 2630 it->push(ime[index].method_addr()); 2631 } 2632 } 2633 } 2634 } 2635 2636 it->push(&_nest_host); 2637 it->push(&_nest_members); 2638 it->push(&_permitted_subclasses); 2639 it->push(&_record_components); 2640 } 2641 2642 #if INCLUDE_CDS 2643 void InstanceKlass::remove_unshareable_info() { 2644 2645 if (is_linked()) { 2646 assert(can_be_verified_at_dumptime(), "must be"); 2647 // Remember this so we can avoid walking the hierarchy at runtime. 2648 set_verified_at_dump_time(); 2649 } 2650 2651 _misc_flags.set_has_init_deps_processed(false); 2652 2653 Klass::remove_unshareable_info(); 2654 2655 if (SystemDictionaryShared::has_class_failed_verification(this)) { 2656 // Classes are attempted to link during dumping and may fail, 2657 // but these classes are still in the dictionary and class list in CLD. 2658 // If the class has failed verification, there is nothing else to remove. 2659 return; 2660 } 2661 2662 // Reset to the 'allocated' state to prevent any premature accessing to 2663 // a shared class at runtime while the class is still being loaded and 2664 // restored. A class' init_state is set to 'loaded' at runtime when it's 2665 // being added to class hierarchy (see InstanceKlass:::add_to_hierarchy()). 2666 _init_state = allocated; 2667 2668 { // Otherwise this needs to take out the Compile_lock. 2669 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint"); 2670 init_implementor(); 2671 } 2672 2673 // Call remove_unshareable_info() on other objects that belong to this class, except 2674 // for constants()->remove_unshareable_info(), which is called in a separate pass in 2675 // ArchiveBuilder::make_klasses_shareable(), 2676 2677 for (int i = 0; i < methods()->length(); i++) { 2678 Method* m = methods()->at(i); 2679 m->remove_unshareable_info(); 2680 } 2681 2682 // do array classes also. 2683 if (array_klasses() != nullptr) { 2684 array_klasses()->remove_unshareable_info(); 2685 } 2686 2687 // These are not allocated from metaspace. They are safe to set to null. 2688 _source_debug_extension = nullptr; 2689 _dep_context = nullptr; 2690 _osr_nmethods_head = nullptr; 2691 #if INCLUDE_JVMTI 2692 _breakpoints = nullptr; 2693 _previous_versions = nullptr; 2694 _cached_class_file = nullptr; 2695 _jvmti_cached_class_field_map = nullptr; 2696 #endif 2697 2698 _init_thread = nullptr; 2699 _methods_jmethod_ids = nullptr; 2700 _jni_ids = nullptr; 2701 _oop_map_cache = nullptr; 2702 if (CDSConfig::is_dumping_method_handles() && HeapShared::is_lambda_proxy_klass(this)) { 2703 // keep _nest_host 2704 } else { 2705 // clear _nest_host to ensure re-load at runtime 2706 _nest_host = nullptr; 2707 } 2708 init_shared_package_entry(); 2709 _dep_context_last_cleaned = 0; 2710 DEBUG_ONLY(_shared_class_load_count = 0); 2711 2712 remove_unshareable_flags(); 2713 } 2714 2715 void InstanceKlass::remove_unshareable_flags() { 2716 // clear all the flags/stats that shouldn't be in the archived version 2717 assert(!is_scratch_class(), "must be"); 2718 assert(!has_been_redefined(), "must be"); 2719 #if INCLUDE_JVMTI 2720 set_is_being_redefined(false); 2721 #endif 2722 set_has_resolved_methods(false); 2723 } 2724 2725 void InstanceKlass::remove_java_mirror() { 2726 Klass::remove_java_mirror(); 2727 2728 // do array classes also. 2729 if (array_klasses() != nullptr) { 2730 array_klasses()->remove_java_mirror(); 2731 } 2732 } 2733 2734 void InstanceKlass::init_shared_package_entry() { 2735 assert(CDSConfig::is_dumping_archive(), "must be"); 2736 #if !INCLUDE_CDS_JAVA_HEAP 2737 _package_entry = nullptr; 2738 #else 2739 if (CDSConfig::is_dumping_full_module_graph()) { 2740 if (defined_by_other_loaders()) { 2741 _package_entry = nullptr; 2742 } else { 2743 _package_entry = PackageEntry::get_archived_entry(_package_entry); 2744 } 2745 } else if (CDSConfig::is_dumping_dynamic_archive() && 2746 CDSConfig::is_using_full_module_graph() && 2747 MetaspaceShared::is_in_shared_metaspace(_package_entry)) { 2748 // _package_entry is an archived package in the base archive. Leave it as is. 2749 } else { 2750 _package_entry = nullptr; 2751 } 2752 ArchivePtrMarker::mark_pointer((address**)&_package_entry); 2753 #endif 2754 } 2755 2756 void InstanceKlass::compute_has_loops_flag_for_methods() { 2757 Array<Method*>* methods = this->methods(); 2758 for (int index = 0; index < methods->length(); ++index) { 2759 Method* m = methods->at(index); 2760 if (!m->is_overpass()) { // work around JDK-8305771 2761 m->compute_has_loops_flag(); 2762 } 2763 } 2764 } 2765 2766 void InstanceKlass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain, 2767 PackageEntry* pkg_entry, TRAPS) { 2768 // InstanceKlass::add_to_hierarchy() sets the init_state to loaded 2769 // before the InstanceKlass is added to the SystemDictionary. Make 2770 // sure the current state is <loaded. 2771 assert(!is_loaded(), "invalid init state"); 2772 assert(!shared_loading_failed(), "Must not try to load failed class again"); 2773 set_package(loader_data, pkg_entry, CHECK); 2774 Klass::restore_unshareable_info(loader_data, protection_domain, CHECK); 2775 2776 Array<Method*>* methods = this->methods(); 2777 int num_methods = methods->length(); 2778 for (int index = 0; index < num_methods; ++index) { 2779 methods->at(index)->restore_unshareable_info(CHECK); 2780 } 2781 #if INCLUDE_JVMTI 2782 if (JvmtiExport::has_redefined_a_class()) { 2783 // Reinitialize vtable because RedefineClasses may have changed some 2784 // entries in this vtable for super classes so the CDS vtable might 2785 // point to old or obsolete entries. RedefineClasses doesn't fix up 2786 // vtables in the shared system dictionary, only the main one. 2787 // It also redefines the itable too so fix that too. 2788 // First fix any default methods that point to a super class that may 2789 // have been redefined. 2790 bool trace_name_printed = false; 2791 adjust_default_methods(&trace_name_printed); 2792 if (verified_at_dump_time()) { 2793 // Initialize vtable and itable for classes which can be verified at dump time. 2794 // Unlinked classes such as old classes with major version < 50 cannot be verified 2795 // at dump time. 2796 vtable().initialize_vtable(); 2797 itable().initialize_itable(); 2798 } 2799 } 2800 #endif // INCLUDE_JVMTI 2801 2802 // restore constant pool resolved references 2803 constants()->restore_unshareable_info(CHECK); 2804 2805 if (array_klasses() != nullptr) { 2806 // To get a consistent list of classes we need MultiArray_lock to ensure 2807 // array classes aren't observed while they are being restored. 2808 RecursiveLocker rl(MultiArray_lock, THREAD); 2809 assert(this == array_klasses()->bottom_klass(), "sanity"); 2810 // Array classes have null protection domain. 2811 // --> see ArrayKlass::complete_create_array_klass() 2812 array_klasses()->restore_unshareable_info(class_loader_data(), Handle(), CHECK); 2813 } 2814 2815 // Initialize @ValueBased class annotation if not already set in the archived klass. 2816 if (DiagnoseSyncOnValueBasedClasses && has_value_based_class_annotation() && !is_value_based()) { 2817 set_is_value_based(); 2818 } 2819 } 2820 2821 // Check if a class or any of its supertypes has a version older than 50. 2822 // CDS will not perform verification of old classes during dump time because 2823 // without changing the old verifier, the verification constraint cannot be 2824 // retrieved during dump time. 2825 // Verification of archived old classes will be performed during run time. 2826 bool InstanceKlass::can_be_verified_at_dumptime() const { 2827 if (MetaspaceShared::is_in_shared_metaspace(this)) { 2828 // This is a class that was dumped into the base archive, so we know 2829 // it was verified at dump time. 2830 return true; 2831 } 2832 if (major_version() < 50 /*JAVA_6_VERSION*/) { 2833 return false; 2834 } 2835 if (java_super() != nullptr && !java_super()->can_be_verified_at_dumptime()) { 2836 return false; 2837 } 2838 Array<InstanceKlass*>* interfaces = local_interfaces(); 2839 int len = interfaces->length(); 2840 for (int i = 0; i < len; i++) { 2841 if (!interfaces->at(i)->can_be_verified_at_dumptime()) { 2842 return false; 2843 } 2844 } 2845 return true; 2846 } 2847 2848 #endif // INCLUDE_CDS 2849 2850 #if INCLUDE_JVMTI 2851 static void clear_all_breakpoints(Method* m) { 2852 m->clear_all_breakpoints(); 2853 } 2854 #endif 2855 2856 void InstanceKlass::unload_class(InstanceKlass* ik) { 2857 2858 if (ik->is_scratch_class()) { 2859 assert(ik->dependencies().is_empty(), "dependencies should be empty for scratch classes"); 2860 return; 2861 } 2862 assert(ik->is_loaded(), "class should be loaded " PTR_FORMAT, p2i(ik)); 2863 2864 // Release dependencies. 2865 ik->dependencies().remove_all_dependents(); 2866 2867 // notify the debugger 2868 if (JvmtiExport::should_post_class_unload()) { 2869 JvmtiExport::post_class_unload(ik); 2870 } 2871 2872 // notify ClassLoadingService of class unload 2873 ClassLoadingService::notify_class_unloaded(ik); 2874 2875 SystemDictionaryShared::handle_class_unloading(ik); 2876 2877 if (log_is_enabled(Info, class, unload)) { 2878 ResourceMark rm; 2879 log_info(class, unload)("unloading class %s " PTR_FORMAT, ik->external_name(), p2i(ik)); 2880 } 2881 2882 Events::log_class_unloading(Thread::current(), ik); 2883 2884 #if INCLUDE_JFR 2885 assert(ik != nullptr, "invariant"); 2886 EventClassUnload event; 2887 event.set_unloadedClass(ik); 2888 event.set_definingClassLoader(ik->class_loader_data()); 2889 event.commit(); 2890 #endif 2891 } 2892 2893 static void method_release_C_heap_structures(Method* m) { 2894 m->release_C_heap_structures(); 2895 } 2896 2897 // Called also by InstanceKlass::deallocate_contents, with false for release_sub_metadata. 2898 void InstanceKlass::release_C_heap_structures(bool release_sub_metadata) { 2899 // Clean up C heap 2900 Klass::release_C_heap_structures(); 2901 2902 // Deallocate and call destructors for MDO mutexes 2903 if (release_sub_metadata) { 2904 methods_do(method_release_C_heap_structures); 2905 } 2906 2907 // Deallocate oop map cache 2908 if (_oop_map_cache != nullptr) { 2909 delete _oop_map_cache; 2910 _oop_map_cache = nullptr; 2911 } 2912 2913 // Deallocate JNI identifiers for jfieldIDs 2914 JNIid::deallocate(jni_ids()); 2915 set_jni_ids(nullptr); 2916 2917 jmethodID* jmeths = methods_jmethod_ids_acquire(); 2918 if (jmeths != nullptr) { 2919 release_set_methods_jmethod_ids(nullptr); 2920 FreeHeap(jmeths); 2921 } 2922 2923 assert(_dep_context == nullptr, 2924 "dependencies should already be cleaned"); 2925 2926 #if INCLUDE_JVMTI 2927 // Deallocate breakpoint records 2928 if (breakpoints() != nullptr) { 2929 methods_do(clear_all_breakpoints); 2930 assert(breakpoints() == nullptr, "should have cleared breakpoints"); 2931 } 2932 2933 // deallocate the cached class file 2934 if (_cached_class_file != nullptr) { 2935 os::free(_cached_class_file); 2936 _cached_class_file = nullptr; 2937 } 2938 #endif 2939 2940 FREE_C_HEAP_ARRAY(char, _source_debug_extension); 2941 2942 if (release_sub_metadata) { 2943 constants()->release_C_heap_structures(); 2944 } 2945 } 2946 2947 // The constant pool is on stack if any of the methods are executing or 2948 // referenced by handles. 2949 bool InstanceKlass::on_stack() const { 2950 return _constants->on_stack(); 2951 } 2952 2953 Symbol* InstanceKlass::source_file_name() const { return _constants->source_file_name(); } 2954 u2 InstanceKlass::source_file_name_index() const { return _constants->source_file_name_index(); } 2955 void InstanceKlass::set_source_file_name_index(u2 sourcefile_index) { _constants->set_source_file_name_index(sourcefile_index); } 2956 2957 // minor and major version numbers of class file 2958 u2 InstanceKlass::minor_version() const { return _constants->minor_version(); } 2959 void InstanceKlass::set_minor_version(u2 minor_version) { _constants->set_minor_version(minor_version); } 2960 u2 InstanceKlass::major_version() const { return _constants->major_version(); } 2961 void InstanceKlass::set_major_version(u2 major_version) { _constants->set_major_version(major_version); } 2962 2963 const InstanceKlass* InstanceKlass::get_klass_version(int version) const { 2964 for (const InstanceKlass* ik = this; ik != nullptr; ik = ik->previous_versions()) { 2965 if (ik->constants()->version() == version) { 2966 return ik; 2967 } 2968 } 2969 return nullptr; 2970 } 2971 2972 void InstanceKlass::set_source_debug_extension(const char* array, int length) { 2973 if (array == nullptr) { 2974 _source_debug_extension = nullptr; 2975 } else { 2976 // Adding one to the attribute length in order to store a null terminator 2977 // character could cause an overflow because the attribute length is 2978 // already coded with an u4 in the classfile, but in practice, it's 2979 // unlikely to happen. 2980 assert((length+1) > length, "Overflow checking"); 2981 char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass); 2982 for (int i = 0; i < length; i++) { 2983 sde[i] = array[i]; 2984 } 2985 sde[length] = '\0'; 2986 _source_debug_extension = sde; 2987 } 2988 } 2989 2990 Symbol* InstanceKlass::generic_signature() const { return _constants->generic_signature(); } 2991 u2 InstanceKlass::generic_signature_index() const { return _constants->generic_signature_index(); } 2992 void InstanceKlass::set_generic_signature_index(u2 sig_index) { _constants->set_generic_signature_index(sig_index); } 2993 2994 const char* InstanceKlass::signature_name() const { 2995 2996 // Get the internal name as a c string 2997 const char* src = (const char*) (name()->as_C_string()); 2998 const int src_length = (int)strlen(src); 2999 3000 char* dest = NEW_RESOURCE_ARRAY(char, src_length + 3); 3001 3002 // Add L as type indicator 3003 int dest_index = 0; 3004 dest[dest_index++] = JVM_SIGNATURE_CLASS; 3005 3006 // Add the actual class name 3007 for (int src_index = 0; src_index < src_length; ) { 3008 dest[dest_index++] = src[src_index++]; 3009 } 3010 3011 if (is_hidden()) { // Replace the last '+' with a '.'. 3012 for (int index = (int)src_length; index > 0; index--) { 3013 if (dest[index] == '+') { 3014 dest[index] = JVM_SIGNATURE_DOT; 3015 break; 3016 } 3017 } 3018 } 3019 3020 // Add the semicolon and the null 3021 dest[dest_index++] = JVM_SIGNATURE_ENDCLASS; 3022 dest[dest_index] = '\0'; 3023 return dest; 3024 } 3025 3026 ModuleEntry* InstanceKlass::module() const { 3027 if (is_hidden() && 3028 in_unnamed_package() && 3029 class_loader_data()->has_class_mirror_holder()) { 3030 // For a non-strong hidden class defined to an unnamed package, 3031 // its (class held) CLD will not have an unnamed module created for it. 3032 // Two choices to find the correct ModuleEntry: 3033 // 1. If hidden class is within a nest, use nest host's module 3034 // 2. Find the unnamed module off from the class loader 3035 // For now option #2 is used since a nest host is not set until 3036 // after the instance class is created in jvm_lookup_define_class(). 3037 if (class_loader_data()->is_boot_class_loader_data()) { 3038 return ClassLoaderData::the_null_class_loader_data()->unnamed_module(); 3039 } else { 3040 oop module = java_lang_ClassLoader::unnamedModule(class_loader_data()->class_loader()); 3041 assert(java_lang_Module::is_instance(module), "Not an instance of java.lang.Module"); 3042 return java_lang_Module::module_entry(module); 3043 } 3044 } 3045 3046 // Class is in a named package 3047 if (!in_unnamed_package()) { 3048 return _package_entry->module(); 3049 } 3050 3051 // Class is in an unnamed package, return its loader's unnamed module 3052 return class_loader_data()->unnamed_module(); 3053 } 3054 3055 bool InstanceKlass::in_javabase_module() const { 3056 return module()->name() == vmSymbols::java_base(); 3057 } 3058 3059 void InstanceKlass::set_package(ClassLoaderData* loader_data, PackageEntry* pkg_entry, TRAPS) { 3060 3061 // ensure java/ packages only loaded by boot or platform builtin loaders 3062 // not needed for shared class since CDS does not archive prohibited classes. 3063 if (!is_shared()) { 3064 check_prohibited_package(name(), loader_data, CHECK); 3065 } 3066 3067 if (is_shared() && _package_entry != nullptr) { 3068 if (CDSConfig::is_using_full_module_graph() && _package_entry == pkg_entry) { 3069 // we can use the saved package 3070 assert(MetaspaceShared::is_in_shared_metaspace(_package_entry), "must be"); 3071 return; 3072 } else { 3073 _package_entry = nullptr; 3074 } 3075 } 3076 3077 // ClassLoader::package_from_class_name has already incremented the refcount of the symbol 3078 // it returns, so we need to decrement it when the current function exits. 3079 TempNewSymbol from_class_name = 3080 (pkg_entry != nullptr) ? nullptr : ClassLoader::package_from_class_name(name()); 3081 3082 Symbol* pkg_name; 3083 if (pkg_entry != nullptr) { 3084 pkg_name = pkg_entry->name(); 3085 } else { 3086 pkg_name = from_class_name; 3087 } 3088 3089 if (pkg_name != nullptr && loader_data != nullptr) { 3090 3091 // Find in class loader's package entry table. 3092 _package_entry = pkg_entry != nullptr ? pkg_entry : loader_data->packages()->lookup_only(pkg_name); 3093 3094 // If the package name is not found in the loader's package 3095 // entry table, it is an indication that the package has not 3096 // been defined. Consider it defined within the unnamed module. 3097 if (_package_entry == nullptr) { 3098 3099 if (!ModuleEntryTable::javabase_defined()) { 3100 // Before java.base is defined during bootstrapping, define all packages in 3101 // the java.base module. If a non-java.base package is erroneously placed 3102 // in the java.base module it will be caught later when java.base 3103 // is defined by ModuleEntryTable::verify_javabase_packages check. 3104 assert(ModuleEntryTable::javabase_moduleEntry() != nullptr, JAVA_BASE_NAME " module is null"); 3105 _package_entry = loader_data->packages()->create_entry_if_absent(pkg_name, ModuleEntryTable::javabase_moduleEntry()); 3106 } else { 3107 assert(loader_data->unnamed_module() != nullptr, "unnamed module is null"); 3108 _package_entry = loader_data->packages()->create_entry_if_absent(pkg_name, loader_data->unnamed_module()); 3109 } 3110 3111 // A package should have been successfully created 3112 DEBUG_ONLY(ResourceMark rm(THREAD)); 3113 assert(_package_entry != nullptr, "Package entry for class %s not found, loader %s", 3114 name()->as_C_string(), loader_data->loader_name_and_id()); 3115 } 3116 3117 if (log_is_enabled(Debug, module)) { 3118 ResourceMark rm(THREAD); 3119 ModuleEntry* m = _package_entry->module(); 3120 log_trace(module)("Setting package: class: %s, package: %s, loader: %s, module: %s", 3121 external_name(), 3122 pkg_name->as_C_string(), 3123 loader_data->loader_name_and_id(), 3124 (m->is_named() ? m->name()->as_C_string() : UNNAMED_MODULE)); 3125 } 3126 } else { 3127 ResourceMark rm(THREAD); 3128 log_trace(module)("Setting package: class: %s, package: unnamed, loader: %s, module: %s", 3129 external_name(), 3130 (loader_data != nullptr) ? loader_data->loader_name_and_id() : "null", 3131 UNNAMED_MODULE); 3132 } 3133 } 3134 3135 // Function set_classpath_index ensures that for a non-null _package_entry 3136 // of the InstanceKlass, the entry is in the boot loader's package entry table. 3137 // It then sets the classpath_index in the package entry record. 3138 // 3139 // The classpath_index field is used to find the entry on the boot loader class 3140 // path for packages with classes loaded by the boot loader from -Xbootclasspath/a 3141 // in an unnamed module. It is also used to indicate (for all packages whose 3142 // classes are loaded by the boot loader) that at least one of the package's 3143 // classes has been loaded. 3144 void InstanceKlass::set_classpath_index(s2 path_index) { 3145 if (_package_entry != nullptr) { 3146 DEBUG_ONLY(PackageEntryTable* pkg_entry_tbl = ClassLoaderData::the_null_class_loader_data()->packages();) 3147 assert(pkg_entry_tbl->lookup_only(_package_entry->name()) == _package_entry, "Should be same"); 3148 assert(path_index != -1, "Unexpected classpath_index"); 3149 _package_entry->set_classpath_index(path_index); 3150 } 3151 } 3152 3153 // different versions of is_same_class_package 3154 3155 bool InstanceKlass::is_same_class_package(const Klass* class2) const { 3156 oop classloader1 = this->class_loader(); 3157 PackageEntry* classpkg1 = this->package(); 3158 if (class2->is_objArray_klass()) { 3159 class2 = ObjArrayKlass::cast(class2)->bottom_klass(); 3160 } 3161 3162 oop classloader2; 3163 PackageEntry* classpkg2; 3164 if (class2->is_instance_klass()) { 3165 classloader2 = class2->class_loader(); 3166 classpkg2 = class2->package(); 3167 } else { 3168 assert(class2->is_typeArray_klass(), "should be type array"); 3169 classloader2 = nullptr; 3170 classpkg2 = nullptr; 3171 } 3172 3173 // Same package is determined by comparing class loader 3174 // and package entries. Both must be the same. This rule 3175 // applies even to classes that are defined in the unnamed 3176 // package, they still must have the same class loader. 3177 if ((classloader1 == classloader2) && (classpkg1 == classpkg2)) { 3178 return true; 3179 } 3180 3181 return false; 3182 } 3183 3184 // return true if this class and other_class are in the same package. Classloader 3185 // and classname information is enough to determine a class's package 3186 bool InstanceKlass::is_same_class_package(oop other_class_loader, 3187 const Symbol* other_class_name) const { 3188 if (class_loader() != other_class_loader) { 3189 return false; 3190 } 3191 if (name()->fast_compare(other_class_name) == 0) { 3192 return true; 3193 } 3194 3195 { 3196 ResourceMark rm; 3197 3198 bool bad_class_name = false; 3199 TempNewSymbol other_pkg = ClassLoader::package_from_class_name(other_class_name, &bad_class_name); 3200 if (bad_class_name) { 3201 return false; 3202 } 3203 // Check that package_from_class_name() returns null, not "", if there is no package. 3204 assert(other_pkg == nullptr || other_pkg->utf8_length() > 0, "package name is empty string"); 3205 3206 const Symbol* const this_package_name = 3207 this->package() != nullptr ? this->package()->name() : nullptr; 3208 3209 if (this_package_name == nullptr || other_pkg == nullptr) { 3210 // One of the two doesn't have a package. Only return true if the other 3211 // one also doesn't have a package. 3212 return this_package_name == other_pkg; 3213 } 3214 3215 // Check if package is identical 3216 return this_package_name->fast_compare(other_pkg) == 0; 3217 } 3218 } 3219 3220 static bool is_prohibited_package_slow(Symbol* class_name) { 3221 // Caller has ResourceMark 3222 int length; 3223 jchar* unicode = class_name->as_unicode(length); 3224 return (length >= 5 && 3225 unicode[0] == 'j' && 3226 unicode[1] == 'a' && 3227 unicode[2] == 'v' && 3228 unicode[3] == 'a' && 3229 unicode[4] == '/'); 3230 } 3231 3232 // Only boot and platform class loaders can define classes in "java/" packages. 3233 void InstanceKlass::check_prohibited_package(Symbol* class_name, 3234 ClassLoaderData* loader_data, 3235 TRAPS) { 3236 if (!loader_data->is_boot_class_loader_data() && 3237 !loader_data->is_platform_class_loader_data() && 3238 class_name != nullptr && class_name->utf8_length() >= 5) { 3239 ResourceMark rm(THREAD); 3240 bool prohibited; 3241 const u1* base = class_name->base(); 3242 if ((base[0] | base[1] | base[2] | base[3] | base[4]) & 0x80) { 3243 prohibited = is_prohibited_package_slow(class_name); 3244 } else { 3245 char* name = class_name->as_C_string(); 3246 prohibited = (strncmp(name, JAVAPKG, JAVAPKG_LEN) == 0 && name[JAVAPKG_LEN] == '/'); 3247 } 3248 if (prohibited) { 3249 TempNewSymbol pkg_name = ClassLoader::package_from_class_name(class_name); 3250 assert(pkg_name != nullptr, "Error in parsing package name starting with 'java/'"); 3251 char* name = pkg_name->as_C_string(); 3252 const char* class_loader_name = loader_data->loader_name_and_id(); 3253 StringUtils::replace_no_expand(name, "/", "."); 3254 const char* msg_text1 = "Class loader (instance of): "; 3255 const char* msg_text2 = " tried to load prohibited package name: "; 3256 size_t len = strlen(msg_text1) + strlen(class_loader_name) + strlen(msg_text2) + strlen(name) + 1; 3257 char* message = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, len); 3258 jio_snprintf(message, len, "%s%s%s%s", msg_text1, class_loader_name, msg_text2, name); 3259 THROW_MSG(vmSymbols::java_lang_SecurityException(), message); 3260 } 3261 } 3262 return; 3263 } 3264 3265 bool InstanceKlass::find_inner_classes_attr(int* ooff, int* noff, TRAPS) const { 3266 constantPoolHandle i_cp(THREAD, constants()); 3267 for (InnerClassesIterator iter(this); !iter.done(); iter.next()) { 3268 int ioff = iter.inner_class_info_index(); 3269 if (ioff != 0) { 3270 // Check to see if the name matches the class we're looking for 3271 // before attempting to find the class. 3272 if (i_cp->klass_name_at_matches(this, ioff)) { 3273 Klass* inner_klass = i_cp->klass_at(ioff, CHECK_false); 3274 if (this == inner_klass) { 3275 *ooff = iter.outer_class_info_index(); 3276 *noff = iter.inner_name_index(); 3277 return true; 3278 } 3279 } 3280 } 3281 } 3282 return false; 3283 } 3284 3285 InstanceKlass* InstanceKlass::compute_enclosing_class(bool* inner_is_member, TRAPS) const { 3286 InstanceKlass* outer_klass = nullptr; 3287 *inner_is_member = false; 3288 int ooff = 0, noff = 0; 3289 bool has_inner_classes_attr = find_inner_classes_attr(&ooff, &noff, THREAD); 3290 if (has_inner_classes_attr) { 3291 constantPoolHandle i_cp(THREAD, constants()); 3292 if (ooff != 0) { 3293 Klass* ok = i_cp->klass_at(ooff, CHECK_NULL); 3294 if (!ok->is_instance_klass()) { 3295 // If the outer class is not an instance klass then it cannot have 3296 // declared any inner classes. 3297 ResourceMark rm(THREAD); 3298 // Names are all known to be < 64k so we know this formatted message is not excessively large. 3299 Exceptions::fthrow( 3300 THREAD_AND_LOCATION, 3301 vmSymbols::java_lang_IncompatibleClassChangeError(), 3302 "%s and %s disagree on InnerClasses attribute", 3303 ok->external_name(), 3304 external_name()); 3305 return nullptr; 3306 } 3307 outer_klass = InstanceKlass::cast(ok); 3308 *inner_is_member = true; 3309 } 3310 if (nullptr == outer_klass) { 3311 // It may be a local class; try for that. 3312 int encl_method_class_idx = enclosing_method_class_index(); 3313 if (encl_method_class_idx != 0) { 3314 Klass* ok = i_cp->klass_at(encl_method_class_idx, CHECK_NULL); 3315 outer_klass = InstanceKlass::cast(ok); 3316 *inner_is_member = false; 3317 } 3318 } 3319 } 3320 3321 // If no inner class attribute found for this class. 3322 if (nullptr == outer_klass) return nullptr; 3323 3324 // Throws an exception if outer klass has not declared k as an inner klass 3325 // We need evidence that each klass knows about the other, or else 3326 // the system could allow a spoof of an inner class to gain access rights. 3327 Reflection::check_for_inner_class(outer_klass, this, *inner_is_member, CHECK_NULL); 3328 return outer_klass; 3329 } 3330 3331 u2 InstanceKlass::compute_modifier_flags() const { 3332 u2 access = access_flags().as_unsigned_short(); 3333 3334 // But check if it happens to be member class. 3335 InnerClassesIterator iter(this); 3336 for (; !iter.done(); iter.next()) { 3337 int ioff = iter.inner_class_info_index(); 3338 // Inner class attribute can be zero, skip it. 3339 // Strange but true: JVM spec. allows null inner class refs. 3340 if (ioff == 0) continue; 3341 3342 // only look at classes that are already loaded 3343 // since we are looking for the flags for our self. 3344 Symbol* inner_name = constants()->klass_name_at(ioff); 3345 if (name() == inner_name) { 3346 // This is really a member class. 3347 access = iter.inner_access_flags(); 3348 break; 3349 } 3350 } 3351 // Remember to strip ACC_SUPER bit 3352 return (access & (~JVM_ACC_SUPER)); 3353 } 3354 3355 jint InstanceKlass::jvmti_class_status() const { 3356 jint result = 0; 3357 3358 if (is_linked()) { 3359 result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED; 3360 } 3361 3362 if (is_initialized()) { 3363 assert(is_linked(), "Class status is not consistent"); 3364 result |= JVMTI_CLASS_STATUS_INITIALIZED; 3365 } 3366 if (is_in_error_state()) { 3367 result |= JVMTI_CLASS_STATUS_ERROR; 3368 } 3369 return result; 3370 } 3371 3372 Method* InstanceKlass::method_at_itable(InstanceKlass* holder, int index, TRAPS) { 3373 bool implements_interface; // initialized by method_at_itable_or_null 3374 Method* m = method_at_itable_or_null(holder, index, 3375 implements_interface); // out parameter 3376 if (m != nullptr) { 3377 assert(implements_interface, "sanity"); 3378 return m; 3379 } else if (implements_interface) { 3380 // Throw AbstractMethodError since corresponding itable slot is empty. 3381 THROW_NULL(vmSymbols::java_lang_AbstractMethodError()); 3382 } else { 3383 // If the interface isn't implemented by the receiver class, 3384 // the VM should throw IncompatibleClassChangeError. 3385 ResourceMark rm(THREAD); 3386 stringStream ss; 3387 bool same_module = (module() == holder->module()); 3388 ss.print("Receiver class %s does not implement " 3389 "the interface %s defining the method to be called " 3390 "(%s%s%s)", 3391 external_name(), holder->external_name(), 3392 (same_module) ? joint_in_module_of_loader(holder) : class_in_module_of_loader(), 3393 (same_module) ? "" : "; ", 3394 (same_module) ? "" : holder->class_in_module_of_loader()); 3395 THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), ss.as_string()); 3396 } 3397 } 3398 3399 Method* InstanceKlass::method_at_itable_or_null(InstanceKlass* holder, int index, bool& implements_interface) { 3400 klassItable itable(this); 3401 for (int i = 0; i < itable.size_offset_table(); i++) { 3402 itableOffsetEntry* offset_entry = itable.offset_entry(i); 3403 if (offset_entry->interface_klass() == holder) { 3404 implements_interface = true; 3405 itableMethodEntry* ime = offset_entry->first_method_entry(this); 3406 Method* m = ime[index].method(); 3407 return m; 3408 } 3409 } 3410 implements_interface = false; 3411 return nullptr; // offset entry not found 3412 } 3413 3414 int InstanceKlass::vtable_index_of_interface_method(Method* intf_method) { 3415 assert(is_linked(), "required"); 3416 assert(intf_method->method_holder()->is_interface(), "not an interface method"); 3417 assert(is_subtype_of(intf_method->method_holder()), "interface not implemented"); 3418 3419 int vtable_index = Method::invalid_vtable_index; 3420 Symbol* name = intf_method->name(); 3421 Symbol* signature = intf_method->signature(); 3422 3423 // First check in default method array 3424 if (!intf_method->is_abstract() && default_methods() != nullptr) { 3425 int index = find_method_index(default_methods(), 3426 name, signature, 3427 Klass::OverpassLookupMode::find, 3428 Klass::StaticLookupMode::find, 3429 Klass::PrivateLookupMode::find); 3430 if (index >= 0) { 3431 vtable_index = default_vtable_indices()->at(index); 3432 } 3433 } 3434 if (vtable_index == Method::invalid_vtable_index) { 3435 // get vtable_index for miranda methods 3436 klassVtable vt = vtable(); 3437 vtable_index = vt.index_of_miranda(name, signature); 3438 } 3439 return vtable_index; 3440 } 3441 3442 #if INCLUDE_JVMTI 3443 // update default_methods for redefineclasses for methods that are 3444 // not yet in the vtable due to concurrent subclass define and superinterface 3445 // redefinition 3446 // Note: those in the vtable, should have been updated via adjust_method_entries 3447 void InstanceKlass::adjust_default_methods(bool* trace_name_printed) { 3448 // search the default_methods for uses of either obsolete or EMCP methods 3449 if (default_methods() != nullptr) { 3450 for (int index = 0; index < default_methods()->length(); index ++) { 3451 Method* old_method = default_methods()->at(index); 3452 if (old_method == nullptr || !old_method->is_old()) { 3453 continue; // skip uninteresting entries 3454 } 3455 assert(!old_method->is_deleted(), "default methods may not be deleted"); 3456 Method* new_method = old_method->get_new_method(); 3457 default_methods()->at_put(index, new_method); 3458 3459 if (log_is_enabled(Info, redefine, class, update)) { 3460 ResourceMark rm; 3461 if (!(*trace_name_printed)) { 3462 log_info(redefine, class, update) 3463 ("adjust: klassname=%s default methods from name=%s", 3464 external_name(), old_method->method_holder()->external_name()); 3465 *trace_name_printed = true; 3466 } 3467 log_debug(redefine, class, update, vtables) 3468 ("default method update: %s(%s) ", 3469 new_method->name()->as_C_string(), new_method->signature()->as_C_string()); 3470 } 3471 } 3472 } 3473 } 3474 #endif // INCLUDE_JVMTI 3475 3476 // On-stack replacement stuff 3477 void InstanceKlass::add_osr_nmethod(nmethod* n) { 3478 assert_lock_strong(NMethodState_lock); 3479 #ifndef PRODUCT 3480 nmethod* prev = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), n->comp_level(), true); 3481 assert(prev == nullptr || !prev->is_in_use() COMPILER2_PRESENT(|| StressRecompilation), 3482 "redundant OSR recompilation detected. memory leak in CodeCache!"); 3483 #endif 3484 // only one compilation can be active 3485 assert(n->is_osr_method(), "wrong kind of nmethod"); 3486 n->set_osr_link(osr_nmethods_head()); 3487 set_osr_nmethods_head(n); 3488 // Raise the highest osr level if necessary 3489 n->method()->set_highest_osr_comp_level(MAX2(n->method()->highest_osr_comp_level(), n->comp_level())); 3490 3491 // Get rid of the osr methods for the same bci that have lower levels. 3492 for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) { 3493 nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true); 3494 if (inv != nullptr && inv->is_in_use()) { 3495 inv->make_not_entrant("OSR invalidation of lower levels"); 3496 } 3497 } 3498 } 3499 3500 // Remove osr nmethod from the list. Return true if found and removed. 3501 bool InstanceKlass::remove_osr_nmethod(nmethod* n) { 3502 // This is a short non-blocking critical region, so the no safepoint check is ok. 3503 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag); 3504 assert(n->is_osr_method(), "wrong kind of nmethod"); 3505 nmethod* last = nullptr; 3506 nmethod* cur = osr_nmethods_head(); 3507 int max_level = CompLevel_none; // Find the max comp level excluding n 3508 Method* m = n->method(); 3509 // Search for match 3510 bool found = false; 3511 while(cur != nullptr && cur != n) { 3512 if (m == cur->method()) { 3513 // Find max level before n 3514 max_level = MAX2(max_level, cur->comp_level()); 3515 } 3516 last = cur; 3517 cur = cur->osr_link(); 3518 } 3519 nmethod* next = nullptr; 3520 if (cur == n) { 3521 found = true; 3522 next = cur->osr_link(); 3523 if (last == nullptr) { 3524 // Remove first element 3525 set_osr_nmethods_head(next); 3526 } else { 3527 last->set_osr_link(next); 3528 } 3529 } 3530 n->set_osr_link(nullptr); 3531 cur = next; 3532 while (cur != nullptr) { 3533 // Find max level after n 3534 if (m == cur->method()) { 3535 max_level = MAX2(max_level, cur->comp_level()); 3536 } 3537 cur = cur->osr_link(); 3538 } 3539 m->set_highest_osr_comp_level(max_level); 3540 return found; 3541 } 3542 3543 int InstanceKlass::mark_osr_nmethods(DeoptimizationScope* deopt_scope, const Method* m) { 3544 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag); 3545 nmethod* osr = osr_nmethods_head(); 3546 int found = 0; 3547 while (osr != nullptr) { 3548 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain"); 3549 if (osr->method() == m) { 3550 deopt_scope->mark(osr); 3551 found++; 3552 } 3553 osr = osr->osr_link(); 3554 } 3555 return found; 3556 } 3557 3558 nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const { 3559 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag); 3560 nmethod* osr = osr_nmethods_head(); 3561 nmethod* best = nullptr; 3562 while (osr != nullptr) { 3563 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain"); 3564 // There can be a time when a c1 osr method exists but we are waiting 3565 // for a c2 version. When c2 completes its osr nmethod we will trash 3566 // the c1 version and only be able to find the c2 version. However 3567 // while we overflow in the c1 code at back branches we don't want to 3568 // try and switch to the same code as we are already running 3569 3570 if (osr->method() == m && 3571 (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) { 3572 if (match_level) { 3573 if (osr->comp_level() == comp_level) { 3574 // Found a match - return it. 3575 return osr; 3576 } 3577 } else { 3578 if (best == nullptr || (osr->comp_level() > best->comp_level())) { 3579 if (osr->comp_level() == CompilationPolicy::highest_compile_level()) { 3580 // Found the best possible - return it. 3581 return osr; 3582 } 3583 best = osr; 3584 } 3585 } 3586 } 3587 osr = osr->osr_link(); 3588 } 3589 3590 assert(match_level == false || best == nullptr, "shouldn't pick up anything if match_level is set"); 3591 if (best != nullptr && best->comp_level() >= comp_level) { 3592 return best; 3593 } 3594 return nullptr; 3595 } 3596 3597 // ----------------------------------------------------------------------------------------------------- 3598 // Printing 3599 3600 #define BULLET " - " 3601 3602 static const char* state_names[] = { 3603 "allocated", "loaded", "linked", "being_initialized", "fully_initialized", "initialization_error" 3604 }; 3605 3606 static void print_vtable(intptr_t* start, int len, outputStream* st) { 3607 for (int i = 0; i < len; i++) { 3608 intptr_t e = start[i]; 3609 st->print("%d : " INTPTR_FORMAT, i, e); 3610 if (MetaspaceObj::is_valid((Metadata*)e)) { 3611 st->print(" "); 3612 ((Metadata*)e)->print_value_on(st); 3613 } 3614 st->cr(); 3615 } 3616 } 3617 3618 static void print_vtable(vtableEntry* start, int len, outputStream* st) { 3619 return print_vtable(reinterpret_cast<intptr_t*>(start), len, st); 3620 } 3621 3622 const char* InstanceKlass::init_state_name() const { 3623 return state_names[init_state()]; 3624 } 3625 3626 void InstanceKlass::print_on(outputStream* st) const { 3627 assert(is_klass(), "must be klass"); 3628 Klass::print_on(st); 3629 3630 st->print(BULLET"instance size: %d", size_helper()); st->cr(); 3631 st->print(BULLET"klass size: %d", size()); st->cr(); 3632 st->print(BULLET"access: "); access_flags().print_on(st); st->cr(); 3633 st->print(BULLET"flags: "); _misc_flags.print_on(st); st->cr(); 3634 st->print(BULLET"state: "); st->print_cr("%s", init_state_name()); 3635 st->print(BULLET"name: "); name()->print_value_on(st); st->cr(); 3636 st->print(BULLET"super: "); Metadata::print_value_on_maybe_null(st, super()); st->cr(); 3637 st->print(BULLET"sub: "); 3638 Klass* sub = subklass(); 3639 int n; 3640 for (n = 0; sub != nullptr; n++, sub = sub->next_sibling()) { 3641 if (n < MaxSubklassPrintSize) { 3642 sub->print_value_on(st); 3643 st->print(" "); 3644 } 3645 } 3646 if (n >= MaxSubklassPrintSize) st->print("(%zd more klasses...)", n - MaxSubklassPrintSize); 3647 st->cr(); 3648 3649 if (is_interface()) { 3650 st->print_cr(BULLET"nof implementors: %d", nof_implementors()); 3651 if (nof_implementors() == 1) { 3652 st->print_cr(BULLET"implementor: "); 3653 st->print(" "); 3654 implementor()->print_value_on(st); 3655 st->cr(); 3656 } 3657 } 3658 3659 st->print(BULLET"arrays: "); Metadata::print_value_on_maybe_null(st, array_klasses()); st->cr(); 3660 st->print(BULLET"methods: "); methods()->print_value_on(st); st->cr(); 3661 if (Verbose || WizardMode) { 3662 Array<Method*>* method_array = methods(); 3663 for (int i = 0; i < method_array->length(); i++) { 3664 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr(); 3665 } 3666 } 3667 st->print(BULLET"method ordering: "); method_ordering()->print_value_on(st); st->cr(); 3668 if (default_methods() != nullptr) { 3669 st->print(BULLET"default_methods: "); default_methods()->print_value_on(st); st->cr(); 3670 if (Verbose) { 3671 Array<Method*>* method_array = default_methods(); 3672 for (int i = 0; i < method_array->length(); i++) { 3673 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr(); 3674 } 3675 } 3676 } 3677 print_on_maybe_null(st, BULLET"default vtable indices: ", default_vtable_indices()); 3678 st->print(BULLET"local interfaces: "); local_interfaces()->print_value_on(st); st->cr(); 3679 st->print(BULLET"trans. interfaces: "); transitive_interfaces()->print_value_on(st); st->cr(); 3680 3681 st->print(BULLET"secondary supers: "); secondary_supers()->print_value_on(st); st->cr(); 3682 3683 st->print(BULLET"hash_slot: %d", hash_slot()); st->cr(); 3684 st->print(BULLET"secondary bitmap: " UINTX_FORMAT_X_0, _secondary_supers_bitmap); st->cr(); 3685 3686 if (secondary_supers() != nullptr) { 3687 if (Verbose) { 3688 bool is_hashed = (_secondary_supers_bitmap != SECONDARY_SUPERS_BITMAP_FULL); 3689 st->print_cr(BULLET"---- secondary supers (%d words):", _secondary_supers->length()); 3690 for (int i = 0; i < _secondary_supers->length(); i++) { 3691 ResourceMark rm; // for external_name() 3692 Klass* secondary_super = _secondary_supers->at(i); 3693 st->print(BULLET"%2d:", i); 3694 if (is_hashed) { 3695 int home_slot = compute_home_slot(secondary_super, _secondary_supers_bitmap); 3696 int distance = (i - home_slot) & SECONDARY_SUPERS_TABLE_MASK; 3697 st->print(" dist:%02d:", distance); 3698 } 3699 st->print_cr(" %p %s", secondary_super, secondary_super->external_name()); 3700 } 3701 } 3702 } 3703 st->print(BULLET"constants: "); constants()->print_value_on(st); st->cr(); 3704 3705 print_on_maybe_null(st, BULLET"class loader data: ", class_loader_data()); 3706 print_on_maybe_null(st, BULLET"source file: ", source_file_name()); 3707 if (source_debug_extension() != nullptr) { 3708 st->print(BULLET"source debug extension: "); 3709 st->print("%s", source_debug_extension()); 3710 st->cr(); 3711 } 3712 print_on_maybe_null(st, BULLET"class annotations: ", class_annotations()); 3713 print_on_maybe_null(st, BULLET"class type annotations: ", class_type_annotations()); 3714 print_on_maybe_null(st, BULLET"field annotations: ", fields_annotations()); 3715 print_on_maybe_null(st, BULLET"field type annotations: ", fields_type_annotations()); 3716 { 3717 bool have_pv = false; 3718 // previous versions are linked together through the InstanceKlass 3719 for (InstanceKlass* pv_node = previous_versions(); 3720 pv_node != nullptr; 3721 pv_node = pv_node->previous_versions()) { 3722 if (!have_pv) 3723 st->print(BULLET"previous version: "); 3724 have_pv = true; 3725 pv_node->constants()->print_value_on(st); 3726 } 3727 if (have_pv) st->cr(); 3728 } 3729 3730 print_on_maybe_null(st, BULLET"generic signature: ", generic_signature()); 3731 st->print(BULLET"inner classes: "); inner_classes()->print_value_on(st); st->cr(); 3732 st->print(BULLET"nest members: "); nest_members()->print_value_on(st); st->cr(); 3733 print_on_maybe_null(st, BULLET"record components: ", record_components()); 3734 st->print(BULLET"permitted subclasses: "); permitted_subclasses()->print_value_on(st); st->cr(); 3735 if (java_mirror() != nullptr) { 3736 st->print(BULLET"java mirror: "); 3737 java_mirror()->print_value_on(st); 3738 st->cr(); 3739 } else { 3740 st->print_cr(BULLET"java mirror: null"); 3741 } 3742 st->print(BULLET"vtable length %d (start addr: " PTR_FORMAT ")", vtable_length(), p2i(start_of_vtable())); st->cr(); 3743 if (vtable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_vtable(), vtable_length(), st); 3744 st->print(BULLET"itable length %d (start addr: " PTR_FORMAT ")", itable_length(), p2i(start_of_itable())); st->cr(); 3745 if (itable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_itable(), itable_length(), st); 3746 st->print_cr(BULLET"---- static fields (%d words):", static_field_size()); 3747 3748 FieldPrinter print_static_field(st); 3749 ((InstanceKlass*)this)->do_local_static_fields(&print_static_field); 3750 st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size()); 3751 FieldPrinter print_nonstatic_field(st); 3752 InstanceKlass* ik = const_cast<InstanceKlass*>(this); 3753 ik->print_nonstatic_fields(&print_nonstatic_field); 3754 3755 st->print(BULLET"non-static oop maps (%d entries): ", nonstatic_oop_map_count()); 3756 OopMapBlock* map = start_of_nonstatic_oop_maps(); 3757 OopMapBlock* end_map = map + nonstatic_oop_map_count(); 3758 while (map < end_map) { 3759 st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1)); 3760 map++; 3761 } 3762 st->cr(); 3763 } 3764 3765 void InstanceKlass::print_value_on(outputStream* st) const { 3766 assert(is_klass(), "must be klass"); 3767 if (Verbose || WizardMode) access_flags().print_on(st); 3768 name()->print_value_on(st); 3769 } 3770 3771 void FieldPrinter::do_field(fieldDescriptor* fd) { 3772 _st->print(BULLET); 3773 if (_obj == nullptr) { 3774 fd->print_on(_st); 3775 _st->cr(); 3776 } else { 3777 fd->print_on_for(_st, _obj); 3778 _st->cr(); 3779 } 3780 } 3781 3782 3783 void InstanceKlass::oop_print_on(oop obj, outputStream* st) { 3784 Klass::oop_print_on(obj, st); 3785 3786 if (this == vmClasses::String_klass()) { 3787 typeArrayOop value = java_lang_String::value(obj); 3788 juint length = java_lang_String::length(obj); 3789 if (value != nullptr && 3790 value->is_typeArray() && 3791 length <= (juint) value->length()) { 3792 st->print(BULLET"string: "); 3793 java_lang_String::print(obj, st); 3794 st->cr(); 3795 } 3796 } 3797 3798 st->print_cr(BULLET"---- fields (total size %zu words):", oop_size(obj)); 3799 FieldPrinter print_field(st, obj); 3800 print_nonstatic_fields(&print_field); 3801 3802 if (this == vmClasses::Class_klass()) { 3803 st->print(BULLET"signature: "); 3804 java_lang_Class::print_signature(obj, st); 3805 st->cr(); 3806 Klass* real_klass = java_lang_Class::as_Klass(obj); 3807 if (real_klass != nullptr && real_klass->is_instance_klass()) { 3808 st->print_cr(BULLET"---- static fields (%d):", java_lang_Class::static_oop_field_count(obj)); 3809 InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field); 3810 } 3811 } else if (this == vmClasses::MethodType_klass()) { 3812 st->print(BULLET"signature: "); 3813 java_lang_invoke_MethodType::print_signature(obj, st); 3814 st->cr(); 3815 } 3816 } 3817 3818 #ifndef PRODUCT 3819 3820 bool InstanceKlass::verify_itable_index(int i) { 3821 int method_count = klassItable::method_count_for_interface(this); 3822 assert(i >= 0 && i < method_count, "index out of bounds"); 3823 return true; 3824 } 3825 3826 #endif //PRODUCT 3827 3828 void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) { 3829 st->print("a "); 3830 name()->print_value_on(st); 3831 obj->print_address_on(st); 3832 if (this == vmClasses::String_klass() 3833 && java_lang_String::value(obj) != nullptr) { 3834 ResourceMark rm; 3835 int len = java_lang_String::length(obj); 3836 int plen = (len < 24 ? len : 12); 3837 char* str = java_lang_String::as_utf8_string(obj, 0, plen); 3838 st->print(" = \"%s\"", str); 3839 if (len > plen) 3840 st->print("...[%d]", len); 3841 } else if (this == vmClasses::Class_klass()) { 3842 Klass* k = java_lang_Class::as_Klass(obj); 3843 st->print(" = "); 3844 if (k != nullptr) { 3845 k->print_value_on(st); 3846 } else { 3847 const char* tname = type2name(java_lang_Class::primitive_type(obj)); 3848 st->print("%s", tname ? tname : "type?"); 3849 } 3850 } else if (this == vmClasses::MethodType_klass()) { 3851 st->print(" = "); 3852 java_lang_invoke_MethodType::print_signature(obj, st); 3853 } else if (java_lang_boxing_object::is_instance(obj)) { 3854 st->print(" = "); 3855 java_lang_boxing_object::print(obj, st); 3856 } else if (this == vmClasses::LambdaForm_klass()) { 3857 oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj); 3858 if (vmentry != nullptr) { 3859 st->print(" => "); 3860 vmentry->print_value_on(st); 3861 } 3862 } else if (this == vmClasses::MemberName_klass()) { 3863 Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj); 3864 if (vmtarget != nullptr) { 3865 st->print(" = "); 3866 vmtarget->print_value_on(st); 3867 } else { 3868 oop clazz = java_lang_invoke_MemberName::clazz(obj); 3869 oop name = java_lang_invoke_MemberName::name(obj); 3870 if (clazz != nullptr) { 3871 clazz->print_value_on(st); 3872 } else { 3873 st->print("null"); 3874 } 3875 st->print("."); 3876 if (name != nullptr) { 3877 name->print_value_on(st); 3878 } else { 3879 st->print("null"); 3880 } 3881 } 3882 } 3883 } 3884 3885 const char* InstanceKlass::internal_name() const { 3886 return external_name(); 3887 } 3888 3889 void InstanceKlass::print_class_load_logging(ClassLoaderData* loader_data, 3890 const ModuleEntry* module_entry, 3891 const ClassFileStream* cfs) const { 3892 3893 if (ClassListWriter::is_enabled()) { 3894 ClassListWriter::write(this, cfs); 3895 } 3896 3897 print_class_load_helper(loader_data, module_entry, cfs); 3898 print_class_load_cause_logging(); 3899 } 3900 3901 void InstanceKlass::print_class_load_helper(ClassLoaderData* loader_data, 3902 const ModuleEntry* module_entry, 3903 const ClassFileStream* cfs) const { 3904 3905 if (!log_is_enabled(Info, class, load)) { 3906 return; 3907 } 3908 3909 ResourceMark rm; 3910 LogMessage(class, load) msg; 3911 stringStream info_stream; 3912 3913 // Name and class hierarchy info 3914 info_stream.print("%s", external_name()); 3915 3916 // Source 3917 if (cfs != nullptr) { 3918 if (cfs->source() != nullptr) { 3919 const char* module_name = (module_entry->name() == nullptr) ? UNNAMED_MODULE : module_entry->name()->as_C_string(); 3920 if (module_name != nullptr) { 3921 // When the boot loader created the stream, it didn't know the module name 3922 // yet. Let's format it now. 3923 if (cfs->from_boot_loader_modules_image()) { 3924 info_stream.print(" source: jrt:/%s", module_name); 3925 } else { 3926 info_stream.print(" source: %s", cfs->source()); 3927 } 3928 } else { 3929 info_stream.print(" source: %s", cfs->source()); 3930 } 3931 } else if (loader_data == ClassLoaderData::the_null_class_loader_data()) { 3932 Thread* current = Thread::current(); 3933 Klass* caller = current->is_Java_thread() ? 3934 JavaThread::cast(current)->security_get_caller_class(1): 3935 nullptr; 3936 // caller can be null, for example, during a JVMTI VM_Init hook 3937 if (caller != nullptr) { 3938 info_stream.print(" source: instance of %s", caller->external_name()); 3939 } else { 3940 // source is unknown 3941 } 3942 } else { 3943 oop class_loader = loader_data->class_loader(); 3944 info_stream.print(" source: %s", class_loader->klass()->external_name()); 3945 } 3946 } else { 3947 assert(this->is_shared(), "must be"); 3948 if (MetaspaceShared::is_shared_dynamic((void*)this)) { 3949 info_stream.print(" source: shared objects file (top)"); 3950 } else { 3951 info_stream.print(" source: shared objects file"); 3952 } 3953 } 3954 3955 msg.info("%s", info_stream.as_string()); 3956 3957 if (log_is_enabled(Debug, class, load)) { 3958 stringStream debug_stream; 3959 3960 // Class hierarchy info 3961 debug_stream.print(" klass: " PTR_FORMAT " super: " PTR_FORMAT, 3962 p2i(this), p2i(superklass())); 3963 3964 // Interfaces 3965 if (local_interfaces() != nullptr && local_interfaces()->length() > 0) { 3966 debug_stream.print(" interfaces:"); 3967 int length = local_interfaces()->length(); 3968 for (int i = 0; i < length; i++) { 3969 debug_stream.print(" " PTR_FORMAT, 3970 p2i(InstanceKlass::cast(local_interfaces()->at(i)))); 3971 } 3972 } 3973 3974 // Class loader 3975 debug_stream.print(" loader: ["); 3976 loader_data->print_value_on(&debug_stream); 3977 debug_stream.print("]"); 3978 3979 // Classfile checksum 3980 if (cfs) { 3981 debug_stream.print(" bytes: %d checksum: %08x", 3982 cfs->length(), 3983 ClassLoader::crc32(0, (const char*)cfs->buffer(), 3984 cfs->length())); 3985 } 3986 3987 msg.debug("%s", debug_stream.as_string()); 3988 } 3989 } 3990 3991 void InstanceKlass::print_class_load_cause_logging() const { 3992 bool log_cause_native = log_is_enabled(Info, class, load, cause, native); 3993 if (log_cause_native || log_is_enabled(Info, class, load, cause)) { 3994 JavaThread* current = JavaThread::current(); 3995 ResourceMark rm(current); 3996 const char* name = external_name(); 3997 3998 if (LogClassLoadingCauseFor == nullptr || 3999 (strcmp("*", LogClassLoadingCauseFor) != 0 && 4000 strstr(name, LogClassLoadingCauseFor) == nullptr)) { 4001 return; 4002 } 4003 4004 // Log Java stack first 4005 { 4006 LogMessage(class, load, cause) msg; 4007 NonInterleavingLogStream info_stream{LogLevelType::Info, msg}; 4008 4009 info_stream.print_cr("Java stack when loading %s:", name); 4010 current->print_stack_on(&info_stream); 4011 } 4012 4013 // Log native stack second 4014 if (log_cause_native) { 4015 // Log to string first so that lines can be indented 4016 stringStream stack_stream; 4017 char buf[O_BUFLEN]; 4018 address lastpc = nullptr; 4019 NativeStackPrinter nsp(current); 4020 nsp.print_stack(&stack_stream, buf, sizeof(buf), lastpc, 4021 true /* print_source_info */, -1 /* max stack */); 4022 4023 LogMessage(class, load, cause, native) msg; 4024 NonInterleavingLogStream info_stream{LogLevelType::Info, msg}; 4025 info_stream.print_cr("Native stack when loading %s:", name); 4026 4027 // Print each native stack line to the log 4028 int size = (int) stack_stream.size(); 4029 char* stack = stack_stream.as_string(); 4030 char* stack_end = stack + size; 4031 char* line_start = stack; 4032 for (char* p = stack; p < stack_end; p++) { 4033 if (*p == '\n') { 4034 *p = '\0'; 4035 info_stream.print_cr("\t%s", line_start); 4036 line_start = p + 1; 4037 } 4038 } 4039 if (line_start < stack_end) { 4040 info_stream.print_cr("\t%s", line_start); 4041 } 4042 } 4043 } 4044 } 4045 4046 // Verification 4047 4048 class VerifyFieldClosure: public BasicOopIterateClosure { 4049 protected: 4050 template <class T> void do_oop_work(T* p) { 4051 oop obj = RawAccess<>::oop_load(p); 4052 if (!oopDesc::is_oop_or_null(obj)) { 4053 tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p2i(p), p2i(obj)); 4054 Universe::print_on(tty); 4055 guarantee(false, "boom"); 4056 } 4057 } 4058 public: 4059 virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); } 4060 virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); } 4061 }; 4062 4063 void InstanceKlass::verify_on(outputStream* st) { 4064 #ifndef PRODUCT 4065 // Avoid redundant verifies, this really should be in product. 4066 if (_verify_count == Universe::verify_count()) return; 4067 _verify_count = Universe::verify_count(); 4068 #endif 4069 4070 // Verify Klass 4071 Klass::verify_on(st); 4072 4073 // Verify that klass is present in ClassLoaderData 4074 guarantee(class_loader_data()->contains_klass(this), 4075 "this class isn't found in class loader data"); 4076 4077 // Verify vtables 4078 if (is_linked()) { 4079 // $$$ This used to be done only for m/s collections. Doing it 4080 // always seemed a valid generalization. (DLD -- 6/00) 4081 vtable().verify(st); 4082 } 4083 4084 // Verify first subklass 4085 if (subklass() != nullptr) { 4086 guarantee(subklass()->is_klass(), "should be klass"); 4087 } 4088 4089 // Verify siblings 4090 Klass* super = this->super(); 4091 Klass* sib = next_sibling(); 4092 if (sib != nullptr) { 4093 if (sib == this) { 4094 fatal("subclass points to itself " PTR_FORMAT, p2i(sib)); 4095 } 4096 4097 guarantee(sib->is_klass(), "should be klass"); 4098 guarantee(sib->super() == super, "siblings should have same superklass"); 4099 } 4100 4101 // Verify local interfaces 4102 if (local_interfaces()) { 4103 Array<InstanceKlass*>* local_interfaces = this->local_interfaces(); 4104 for (int j = 0; j < local_interfaces->length(); j++) { 4105 InstanceKlass* e = local_interfaces->at(j); 4106 guarantee(e->is_klass() && e->is_interface(), "invalid local interface"); 4107 } 4108 } 4109 4110 // Verify transitive interfaces 4111 if (transitive_interfaces() != nullptr) { 4112 Array<InstanceKlass*>* transitive_interfaces = this->transitive_interfaces(); 4113 for (int j = 0; j < transitive_interfaces->length(); j++) { 4114 InstanceKlass* e = transitive_interfaces->at(j); 4115 guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface"); 4116 } 4117 } 4118 4119 // Verify methods 4120 if (methods() != nullptr) { 4121 Array<Method*>* methods = this->methods(); 4122 for (int j = 0; j < methods->length(); j++) { 4123 guarantee(methods->at(j)->is_method(), "non-method in methods array"); 4124 } 4125 for (int j = 0; j < methods->length() - 1; j++) { 4126 Method* m1 = methods->at(j); 4127 Method* m2 = methods->at(j + 1); 4128 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly"); 4129 } 4130 } 4131 4132 // Verify method ordering 4133 if (method_ordering() != nullptr) { 4134 Array<int>* method_ordering = this->method_ordering(); 4135 int length = method_ordering->length(); 4136 if (JvmtiExport::can_maintain_original_method_order() || 4137 ((CDSConfig::is_using_archive() || CDSConfig::is_dumping_archive()) && length != 0)) { 4138 guarantee(length == methods()->length(), "invalid method ordering length"); 4139 jlong sum = 0; 4140 for (int j = 0; j < length; j++) { 4141 int original_index = method_ordering->at(j); 4142 guarantee(original_index >= 0, "invalid method ordering index"); 4143 guarantee(original_index < length, "invalid method ordering index"); 4144 sum += original_index; 4145 } 4146 // Verify sum of indices 0,1,...,length-1 4147 guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum"); 4148 } else { 4149 guarantee(length == 0, "invalid method ordering length"); 4150 } 4151 } 4152 4153 // Verify default methods 4154 if (default_methods() != nullptr) { 4155 Array<Method*>* methods = this->default_methods(); 4156 for (int j = 0; j < methods->length(); j++) { 4157 guarantee(methods->at(j)->is_method(), "non-method in methods array"); 4158 } 4159 for (int j = 0; j < methods->length() - 1; j++) { 4160 Method* m1 = methods->at(j); 4161 Method* m2 = methods->at(j + 1); 4162 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly"); 4163 } 4164 } 4165 4166 // Verify JNI static field identifiers 4167 if (jni_ids() != nullptr) { 4168 jni_ids()->verify(this); 4169 } 4170 4171 // Verify other fields 4172 if (constants() != nullptr) { 4173 guarantee(constants()->is_constantPool(), "should be constant pool"); 4174 } 4175 } 4176 4177 void InstanceKlass::oop_verify_on(oop obj, outputStream* st) { 4178 Klass::oop_verify_on(obj, st); 4179 VerifyFieldClosure blk; 4180 obj->oop_iterate(&blk); 4181 } 4182 4183 4184 // JNIid class for jfieldIDs only 4185 // Note to reviewers: 4186 // These JNI functions are just moved over to column 1 and not changed 4187 // in the compressed oops workspace. 4188 JNIid::JNIid(Klass* holder, int offset, JNIid* next) { 4189 _holder = holder; 4190 _offset = offset; 4191 _next = next; 4192 DEBUG_ONLY(_is_static_field_id = false;) 4193 } 4194 4195 4196 JNIid* JNIid::find(int offset) { 4197 JNIid* current = this; 4198 while (current != nullptr) { 4199 if (current->offset() == offset) return current; 4200 current = current->next(); 4201 } 4202 return nullptr; 4203 } 4204 4205 void JNIid::deallocate(JNIid* current) { 4206 while (current != nullptr) { 4207 JNIid* next = current->next(); 4208 delete current; 4209 current = next; 4210 } 4211 } 4212 4213 4214 void JNIid::verify(Klass* holder) { 4215 int first_field_offset = InstanceMirrorKlass::offset_of_static_fields(); 4216 int end_field_offset; 4217 end_field_offset = first_field_offset + (InstanceKlass::cast(holder)->static_field_size() * wordSize); 4218 4219 JNIid* current = this; 4220 while (current != nullptr) { 4221 guarantee(current->holder() == holder, "Invalid klass in JNIid"); 4222 #ifdef ASSERT 4223 int o = current->offset(); 4224 if (current->is_static_field_id()) { 4225 guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid"); 4226 } 4227 #endif 4228 current = current->next(); 4229 } 4230 } 4231 4232 void InstanceKlass::set_init_state(ClassState state) { 4233 #ifdef ASSERT 4234 bool good_state = is_shared() ? (_init_state <= state) 4235 : (_init_state < state); 4236 assert(good_state || state == allocated, "illegal state transition"); 4237 #endif 4238 assert(_init_thread == nullptr, "should be cleared before state change"); 4239 Atomic::release_store(&_init_state, state); 4240 } 4241 4242 #if INCLUDE_JVMTI 4243 4244 // RedefineClasses() support for previous versions 4245 4246 // Globally, there is at least one previous version of a class to walk 4247 // during class unloading, which is saved because old methods in the class 4248 // are still running. Otherwise the previous version list is cleaned up. 4249 bool InstanceKlass::_should_clean_previous_versions = false; 4250 4251 // Returns true if there are previous versions of a class for class 4252 // unloading only. Also resets the flag to false. purge_previous_version 4253 // will set the flag to true if there are any left, i.e., if there's any 4254 // work to do for next time. This is to avoid the expensive code cache 4255 // walk in CLDG::clean_deallocate_lists(). 4256 bool InstanceKlass::should_clean_previous_versions_and_reset() { 4257 bool ret = _should_clean_previous_versions; 4258 log_trace(redefine, class, iklass, purge)("Class unloading: should_clean_previous_versions = %s", 4259 ret ? "true" : "false"); 4260 _should_clean_previous_versions = false; 4261 return ret; 4262 } 4263 4264 // This nulls out jmethodIDs for all methods in 'klass' 4265 // It needs to be called explicitly for all previous versions of a class because these may not be cleaned up 4266 // during class unloading. 4267 // We can not use the jmethodID cache associated with klass directly because the 'previous' versions 4268 // do not have the jmethodID cache filled in. Instead, we need to lookup jmethodID for each method and this 4269 // is expensive - O(n) for one jmethodID lookup. For all contained methods it is O(n^2). 4270 // The reason for expensive jmethodID lookup for each method is that there is no direct link between method and jmethodID. 4271 void InstanceKlass::clear_jmethod_ids(InstanceKlass* klass) { 4272 Array<Method*>* method_refs = klass->methods(); 4273 for (int k = 0; k < method_refs->length(); k++) { 4274 Method* method = method_refs->at(k); 4275 if (method != nullptr && method->is_obsolete()) { 4276 method->clear_jmethod_id(); 4277 } 4278 } 4279 } 4280 4281 // Purge previous versions before adding new previous versions of the class and 4282 // during class unloading. 4283 void InstanceKlass::purge_previous_version_list() { 4284 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint"); 4285 assert(has_been_redefined(), "Should only be called for main class"); 4286 4287 // Quick exit. 4288 if (previous_versions() == nullptr) { 4289 return; 4290 } 4291 4292 // This klass has previous versions so see what we can cleanup 4293 // while it is safe to do so. 4294 4295 int deleted_count = 0; // leave debugging breadcrumbs 4296 int live_count = 0; 4297 ClassLoaderData* loader_data = class_loader_data(); 4298 assert(loader_data != nullptr, "should never be null"); 4299 4300 ResourceMark rm; 4301 log_trace(redefine, class, iklass, purge)("%s: previous versions", external_name()); 4302 4303 // previous versions are linked together through the InstanceKlass 4304 InstanceKlass* pv_node = previous_versions(); 4305 InstanceKlass* last = this; 4306 int version = 0; 4307 4308 // check the previous versions list 4309 for (; pv_node != nullptr; ) { 4310 4311 ConstantPool* pvcp = pv_node->constants(); 4312 assert(pvcp != nullptr, "cp ref was unexpectedly cleared"); 4313 4314 if (!pvcp->on_stack()) { 4315 // If the constant pool isn't on stack, none of the methods 4316 // are executing. Unlink this previous_version. 4317 // The previous version InstanceKlass is on the ClassLoaderData deallocate list 4318 // so will be deallocated during the next phase of class unloading. 4319 log_trace(redefine, class, iklass, purge) 4320 ("previous version " PTR_FORMAT " is dead.", p2i(pv_node)); 4321 // Unlink from previous version list. 4322 assert(pv_node->class_loader_data() == loader_data, "wrong loader_data"); 4323 InstanceKlass* next = pv_node->previous_versions(); 4324 clear_jmethod_ids(pv_node); // jmethodID maintenance for the unloaded class 4325 pv_node->link_previous_versions(nullptr); // point next to null 4326 last->link_previous_versions(next); 4327 // Delete this node directly. Nothing is referring to it and we don't 4328 // want it to increase the counter for metadata to delete in CLDG. 4329 MetadataFactory::free_metadata(loader_data, pv_node); 4330 pv_node = next; 4331 deleted_count++; 4332 version++; 4333 continue; 4334 } else { 4335 assert(pvcp->pool_holder() != nullptr, "Constant pool with no holder"); 4336 guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack"); 4337 live_count++; 4338 if (pvcp->is_shared()) { 4339 // Shared previous versions can never be removed so no cleaning is needed. 4340 log_trace(redefine, class, iklass, purge)("previous version " PTR_FORMAT " is shared", p2i(pv_node)); 4341 } else { 4342 // Previous version alive, set that clean is needed for next time. 4343 _should_clean_previous_versions = true; 4344 log_trace(redefine, class, iklass, purge)("previous version " PTR_FORMAT " is alive", p2i(pv_node)); 4345 } 4346 } 4347 4348 // next previous version 4349 last = pv_node; 4350 pv_node = pv_node->previous_versions(); 4351 version++; 4352 } 4353 log_trace(redefine, class, iklass, purge) 4354 ("previous version stats: live=%d, deleted=%d", live_count, deleted_count); 4355 } 4356 4357 void InstanceKlass::mark_newly_obsolete_methods(Array<Method*>* old_methods, 4358 int emcp_method_count) { 4359 int obsolete_method_count = old_methods->length() - emcp_method_count; 4360 4361 if (emcp_method_count != 0 && obsolete_method_count != 0 && 4362 _previous_versions != nullptr) { 4363 // We have a mix of obsolete and EMCP methods so we have to 4364 // clear out any matching EMCP method entries the hard way. 4365 int local_count = 0; 4366 for (int i = 0; i < old_methods->length(); i++) { 4367 Method* old_method = old_methods->at(i); 4368 if (old_method->is_obsolete()) { 4369 // only obsolete methods are interesting 4370 Symbol* m_name = old_method->name(); 4371 Symbol* m_signature = old_method->signature(); 4372 4373 // previous versions are linked together through the InstanceKlass 4374 int j = 0; 4375 for (InstanceKlass* prev_version = _previous_versions; 4376 prev_version != nullptr; 4377 prev_version = prev_version->previous_versions(), j++) { 4378 4379 Array<Method*>* method_refs = prev_version->methods(); 4380 for (int k = 0; k < method_refs->length(); k++) { 4381 Method* method = method_refs->at(k); 4382 4383 if (!method->is_obsolete() && 4384 method->name() == m_name && 4385 method->signature() == m_signature) { 4386 // The current RedefineClasses() call has made all EMCP 4387 // versions of this method obsolete so mark it as obsolete 4388 log_trace(redefine, class, iklass, add) 4389 ("%s(%s): flush obsolete method @%d in version @%d", 4390 m_name->as_C_string(), m_signature->as_C_string(), k, j); 4391 4392 method->set_is_obsolete(); 4393 break; 4394 } 4395 } 4396 4397 // The previous loop may not find a matching EMCP method, but 4398 // that doesn't mean that we can optimize and not go any 4399 // further back in the PreviousVersion generations. The EMCP 4400 // method for this generation could have already been made obsolete, 4401 // but there still may be an older EMCP method that has not 4402 // been made obsolete. 4403 } 4404 4405 if (++local_count >= obsolete_method_count) { 4406 // no more obsolete methods so bail out now 4407 break; 4408 } 4409 } 4410 } 4411 } 4412 } 4413 4414 // Save the scratch_class as the previous version if any of the methods are running. 4415 // The previous_versions are used to set breakpoints in EMCP methods and they are 4416 // also used to clean MethodData links to redefined methods that are no longer running. 4417 void InstanceKlass::add_previous_version(InstanceKlass* scratch_class, 4418 int emcp_method_count) { 4419 assert(Thread::current()->is_VM_thread(), 4420 "only VMThread can add previous versions"); 4421 4422 ResourceMark rm; 4423 log_trace(redefine, class, iklass, add) 4424 ("adding previous version ref for %s, EMCP_cnt=%d", scratch_class->external_name(), emcp_method_count); 4425 4426 // Clean out old previous versions for this class 4427 purge_previous_version_list(); 4428 4429 // Mark newly obsolete methods in remaining previous versions. An EMCP method from 4430 // a previous redefinition may be made obsolete by this redefinition. 4431 Array<Method*>* old_methods = scratch_class->methods(); 4432 mark_newly_obsolete_methods(old_methods, emcp_method_count); 4433 4434 // If the constant pool for this previous version of the class 4435 // is not marked as being on the stack, then none of the methods 4436 // in this previous version of the class are on the stack so 4437 // we don't need to add this as a previous version. 4438 ConstantPool* cp_ref = scratch_class->constants(); 4439 if (!cp_ref->on_stack()) { 4440 log_trace(redefine, class, iklass, add)("scratch class not added; no methods are running"); 4441 scratch_class->class_loader_data()->add_to_deallocate_list(scratch_class); 4442 return; 4443 } 4444 4445 // Add previous version if any methods are still running or if this is 4446 // a shared class which should never be removed. 4447 assert(scratch_class->previous_versions() == nullptr, "shouldn't have a previous version"); 4448 scratch_class->link_previous_versions(previous_versions()); 4449 link_previous_versions(scratch_class); 4450 if (cp_ref->is_shared()) { 4451 log_trace(redefine, class, iklass, add) ("scratch class added; class is shared"); 4452 } else { 4453 // We only set clean_previous_versions flag for processing during class 4454 // unloading for non-shared classes. 4455 _should_clean_previous_versions = true; 4456 log_trace(redefine, class, iklass, add) ("scratch class added; one of its methods is on_stack."); 4457 } 4458 } // end add_previous_version() 4459 4460 #endif // INCLUDE_JVMTI 4461 4462 Method* InstanceKlass::method_with_idnum(int idnum) const { 4463 Method* m = nullptr; 4464 if (idnum < methods()->length()) { 4465 m = methods()->at(idnum); 4466 } 4467 if (m == nullptr || m->method_idnum() != idnum) { 4468 for (int index = 0; index < methods()->length(); ++index) { 4469 m = methods()->at(index); 4470 if (m->method_idnum() == idnum) { 4471 return m; 4472 } 4473 } 4474 // None found, return null for the caller to handle. 4475 return nullptr; 4476 } 4477 return m; 4478 } 4479 4480 4481 Method* InstanceKlass::method_with_orig_idnum(int idnum) const { 4482 if (idnum >= methods()->length()) { 4483 return nullptr; 4484 } 4485 Method* m = methods()->at(idnum); 4486 if (m != nullptr && m->orig_method_idnum() == idnum) { 4487 return m; 4488 } 4489 // Obsolete method idnum does not match the original idnum 4490 for (int index = 0; index < methods()->length(); ++index) { 4491 m = methods()->at(index); 4492 if (m->orig_method_idnum() == idnum) { 4493 return m; 4494 } 4495 } 4496 // None found, return null for the caller to handle. 4497 return nullptr; 4498 } 4499 4500 4501 Method* InstanceKlass::method_with_orig_idnum(int idnum, int version) const { 4502 const InstanceKlass* holder = get_klass_version(version); 4503 if (holder == nullptr) { 4504 return nullptr; // The version of klass is gone, no method is found 4505 } 4506 return holder->method_with_orig_idnum(idnum); 4507 } 4508 4509 #if INCLUDE_JVMTI 4510 JvmtiCachedClassFileData* InstanceKlass::get_cached_class_file() { 4511 return _cached_class_file; 4512 } 4513 4514 jint InstanceKlass::get_cached_class_file_len() { 4515 return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file); 4516 } 4517 4518 unsigned char * InstanceKlass::get_cached_class_file_bytes() { 4519 return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file); 4520 } 4521 #endif 4522 4523 // Make a step iterating over the class hierarchy under the root class. 4524 // Skips subclasses if requested. 4525 void ClassHierarchyIterator::next() { 4526 assert(_current != nullptr, "required"); 4527 if (_visit_subclasses && _current->subklass() != nullptr) { 4528 _current = _current->subklass(); 4529 return; // visit next subclass 4530 } 4531 _visit_subclasses = true; // reset 4532 while (_current->next_sibling() == nullptr && _current != _root) { 4533 _current = _current->superklass(); // backtrack; no more sibling subclasses left 4534 } 4535 if (_current == _root) { 4536 // Iteration is over (back at root after backtracking). Invalidate the iterator. 4537 _current = nullptr; 4538 return; 4539 } 4540 _current = _current->next_sibling(); 4541 return; // visit next sibling subclass 4542 }