1 /* 2 * Copyright (c) 1997, 2023, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25 #include "precompiled.hpp" 26 #include "cds/archiveUtils.hpp" 27 #include "cds/classListWriter.hpp" 28 #include "cds/heapShared.hpp" 29 #include "cds/metaspaceShared.hpp" 30 #include "classfile/classFileParser.hpp" 31 #include "classfile/classFileStream.hpp" 32 #include "classfile/classLoader.hpp" 33 #include "classfile/classLoaderData.inline.hpp" 34 #include "classfile/javaClasses.hpp" 35 #include "classfile/moduleEntry.hpp" 36 #include "classfile/systemDictionary.hpp" 37 #include "classfile/systemDictionaryShared.hpp" 38 #include "classfile/verifier.hpp" 39 #include "classfile/vmClasses.hpp" 40 #include "classfile/vmSymbols.hpp" 41 #include "code/codeCache.hpp" 42 #include "code/dependencyContext.hpp" 43 #include "compiler/compilationPolicy.hpp" 44 #include "compiler/compileBroker.hpp" 45 #include "gc/shared/collectedHeap.inline.hpp" 46 #include "interpreter/bytecodeStream.hpp" 47 #include "interpreter/oopMapCache.hpp" 48 #include "interpreter/rewriter.hpp" 49 #include "jvm.h" 50 #include "jvmtifiles/jvmti.h" 51 #include "logging/log.hpp" 52 #include "logging/logMessage.hpp" 53 #include "logging/logStream.hpp" 54 #include "memory/allocation.inline.hpp" 55 #include "memory/iterator.inline.hpp" 56 #include "memory/metadataFactory.hpp" 57 #include "memory/metaspaceClosure.hpp" 58 #include "memory/oopFactory.hpp" 59 #include "memory/resourceArea.hpp" 60 #include "memory/universe.hpp" 61 #include "oops/fieldStreams.inline.hpp" 62 #include "oops/constantPool.hpp" 63 #include "oops/instanceClassLoaderKlass.hpp" 64 #include "oops/instanceKlass.inline.hpp" 65 #include "oops/instanceMirrorKlass.hpp" 66 #include "oops/instanceOop.hpp" 67 #include "oops/instanceStackChunkKlass.hpp" 68 #include "oops/klass.inline.hpp" 69 #include "oops/method.hpp" 70 #include "oops/oop.inline.hpp" 71 #include "oops/recordComponent.hpp" 72 #include "oops/symbol.hpp" 73 #include "oops/inlineKlass.hpp" 74 #include "prims/jvmtiExport.hpp" 75 #include "prims/jvmtiRedefineClasses.hpp" 76 #include "prims/jvmtiThreadState.hpp" 77 #include "prims/methodComparator.hpp" 78 #include "runtime/arguments.hpp" 79 #include "runtime/deoptimization.hpp" 80 #include "runtime/atomic.hpp" 81 #include "runtime/fieldDescriptor.inline.hpp" 82 #include "runtime/handles.inline.hpp" 83 #include "runtime/javaCalls.hpp" 84 #include "runtime/javaThread.inline.hpp" 85 #include "runtime/mutexLocker.hpp" 86 #include "runtime/orderAccess.hpp" 87 #include "runtime/os.inline.hpp" 88 #include "runtime/reflectionUtils.hpp" 89 #include "runtime/threads.hpp" 90 #include "services/classLoadingService.hpp" 91 #include "services/finalizerService.hpp" 92 #include "services/threadService.hpp" 93 #include "utilities/dtrace.hpp" 94 #include "utilities/events.hpp" 95 #include "utilities/macros.hpp" 96 #include "utilities/stringUtils.hpp" 97 #include "utilities/pair.hpp" 98 #ifdef COMPILER1 99 #include "c1/c1_Compiler.hpp" 100 #endif 101 #if INCLUDE_JFR 102 #include "jfr/jfrEvents.hpp" 103 #endif 104 105 #ifdef DTRACE_ENABLED 106 107 108 #define HOTSPOT_CLASS_INITIALIZATION_required HOTSPOT_CLASS_INITIALIZATION_REQUIRED 109 #define HOTSPOT_CLASS_INITIALIZATION_recursive HOTSPOT_CLASS_INITIALIZATION_RECURSIVE 110 #define HOTSPOT_CLASS_INITIALIZATION_concurrent HOTSPOT_CLASS_INITIALIZATION_CONCURRENT 111 #define HOTSPOT_CLASS_INITIALIZATION_erroneous HOTSPOT_CLASS_INITIALIZATION_ERRONEOUS 112 #define HOTSPOT_CLASS_INITIALIZATION_super__failed HOTSPOT_CLASS_INITIALIZATION_SUPER_FAILED 113 #define HOTSPOT_CLASS_INITIALIZATION_clinit HOTSPOT_CLASS_INITIALIZATION_CLINIT 114 #define HOTSPOT_CLASS_INITIALIZATION_error HOTSPOT_CLASS_INITIALIZATION_ERROR 115 #define HOTSPOT_CLASS_INITIALIZATION_end HOTSPOT_CLASS_INITIALIZATION_END 116 #define DTRACE_CLASSINIT_PROBE(type, thread_type) \ 117 { \ 118 char* data = nullptr; \ 119 int len = 0; \ 120 Symbol* clss_name = name(); \ 121 if (clss_name != nullptr) { \ 122 data = (char*)clss_name->bytes(); \ 123 len = clss_name->utf8_length(); \ 124 } \ 125 HOTSPOT_CLASS_INITIALIZATION_##type( \ 126 data, len, (void*)class_loader(), thread_type); \ 127 } 128 129 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait) \ 130 { \ 131 char* data = nullptr; \ 132 int len = 0; \ 133 Symbol* clss_name = name(); \ 134 if (clss_name != nullptr) { \ 135 data = (char*)clss_name->bytes(); \ 136 len = clss_name->utf8_length(); \ 137 } \ 138 HOTSPOT_CLASS_INITIALIZATION_##type( \ 139 data, len, (void*)class_loader(), thread_type, wait); \ 140 } 141 142 #else // ndef DTRACE_ENABLED 143 144 #define DTRACE_CLASSINIT_PROBE(type, thread_type) 145 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait) 146 147 #endif // ndef DTRACE_ENABLED 148 149 bool InstanceKlass::_finalization_enabled = true; 150 151 static inline bool is_class_loader(const Symbol* class_name, 152 const ClassFileParser& parser) { 153 assert(class_name != nullptr, "invariant"); 154 155 if (class_name == vmSymbols::java_lang_ClassLoader()) { 156 return true; 157 } 158 159 if (vmClasses::ClassLoader_klass_loaded()) { 160 const Klass* const super_klass = parser.super_klass(); 161 if (super_klass != nullptr) { 162 if (super_klass->is_subtype_of(vmClasses::ClassLoader_klass())) { 163 return true; 164 } 165 } 166 } 167 return false; 168 } 169 170 bool InstanceKlass::field_is_null_free_inline_type(int index) const { 171 return field(index).field_flags().is_null_free_inline_type(); 172 } 173 174 static inline bool is_stack_chunk_class(const Symbol* class_name, 175 const ClassLoaderData* loader_data) { 176 return (class_name == vmSymbols::jdk_internal_vm_StackChunk() && 177 loader_data->is_the_null_class_loader_data()); 178 } 179 180 // private: called to verify that k is a static member of this nest. 181 // We know that k is an instance class in the same package and hence the 182 // same classloader. 183 bool InstanceKlass::has_nest_member(JavaThread* current, InstanceKlass* k) const { 184 assert(!is_hidden(), "unexpected hidden class"); 185 if (_nest_members == nullptr || _nest_members == Universe::the_empty_short_array()) { 186 if (log_is_enabled(Trace, class, nestmates)) { 187 ResourceMark rm(current); 188 log_trace(class, nestmates)("Checked nest membership of %s in non-nest-host class %s", 189 k->external_name(), this->external_name()); 190 } 191 return false; 192 } 193 194 if (log_is_enabled(Trace, class, nestmates)) { 195 ResourceMark rm(current); 196 log_trace(class, nestmates)("Checking nest membership of %s in %s", 197 k->external_name(), this->external_name()); 198 } 199 200 // Check for the named class in _nest_members. 201 // We don't resolve, or load, any classes. 202 for (int i = 0; i < _nest_members->length(); i++) { 203 int cp_index = _nest_members->at(i); 204 Symbol* name = _constants->klass_name_at(cp_index); 205 if (name == k->name()) { 206 log_trace(class, nestmates)("- named class found at nest_members[%d] => cp[%d]", i, cp_index); 207 return true; 208 } 209 } 210 log_trace(class, nestmates)("- class is NOT a nest member!"); 211 return false; 212 } 213 214 // Called to verify that k is a permitted subclass of this class 215 bool InstanceKlass::has_as_permitted_subclass(const InstanceKlass* k) const { 216 Thread* current = Thread::current(); 217 assert(k != nullptr, "sanity check"); 218 assert(_permitted_subclasses != nullptr && _permitted_subclasses != Universe::the_empty_short_array(), 219 "unexpected empty _permitted_subclasses array"); 220 221 if (log_is_enabled(Trace, class, sealed)) { 222 ResourceMark rm(current); 223 log_trace(class, sealed)("Checking for permitted subclass of %s in %s", 224 k->external_name(), this->external_name()); 225 } 226 227 // Check that the class and its super are in the same module. 228 if (k->module() != this->module()) { 229 ResourceMark rm(current); 230 log_trace(class, sealed)("Check failed for same module of permitted subclass %s and sealed class %s", 231 k->external_name(), this->external_name()); 232 return false; 233 } 234 235 if (!k->is_public() && !is_same_class_package(k)) { 236 ResourceMark rm(current); 237 log_trace(class, sealed)("Check failed, subclass %s not public and not in the same package as sealed class %s", 238 k->external_name(), this->external_name()); 239 return false; 240 } 241 242 for (int i = 0; i < _permitted_subclasses->length(); i++) { 243 int cp_index = _permitted_subclasses->at(i); 244 Symbol* name = _constants->klass_name_at(cp_index); 245 if (name == k->name()) { 246 log_trace(class, sealed)("- Found it at permitted_subclasses[%d] => cp[%d]", i, cp_index); 247 return true; 248 } 249 } 250 log_trace(class, sealed)("- class is NOT a permitted subclass!"); 251 return false; 252 } 253 254 // Return nest-host class, resolving, validating and saving it if needed. 255 // In cases where this is called from a thread that cannot do classloading 256 // (such as a native JIT thread) then we simply return null, which in turn 257 // causes the access check to return false. Such code will retry the access 258 // from a more suitable environment later. Otherwise the _nest_host is always 259 // set once this method returns. 260 // Any errors from nest-host resolution must be preserved so they can be queried 261 // from higher-level access checking code, and reported as part of access checking 262 // exceptions. 263 // VirtualMachineErrors are propagated with a null return. 264 // Under any conditions where the _nest_host can be set to non-null the resulting 265 // value of it and, if applicable, the nest host resolution/validation error, 266 // are idempotent. 267 InstanceKlass* InstanceKlass::nest_host(TRAPS) { 268 InstanceKlass* nest_host_k = _nest_host; 269 if (nest_host_k != nullptr) { 270 return nest_host_k; 271 } 272 273 ResourceMark rm(THREAD); 274 275 // need to resolve and save our nest-host class. 276 if (_nest_host_index != 0) { // we have a real nest_host 277 // Before trying to resolve check if we're in a suitable context 278 bool can_resolve = THREAD->can_call_java(); 279 if (!can_resolve && !_constants->tag_at(_nest_host_index).is_klass()) { 280 log_trace(class, nestmates)("Rejected resolution of nest-host of %s in unsuitable thread", 281 this->external_name()); 282 return nullptr; // sentinel to say "try again from a different context" 283 } 284 285 log_trace(class, nestmates)("Resolving nest-host of %s using cp entry for %s", 286 this->external_name(), 287 _constants->klass_name_at(_nest_host_index)->as_C_string()); 288 289 Klass* k = _constants->klass_at(_nest_host_index, THREAD); 290 if (HAS_PENDING_EXCEPTION) { 291 if (PENDING_EXCEPTION->is_a(vmClasses::VirtualMachineError_klass())) { 292 return nullptr; // propagate VMEs 293 } 294 stringStream ss; 295 char* target_host_class = _constants->klass_name_at(_nest_host_index)->as_C_string(); 296 ss.print("Nest host resolution of %s with host %s failed: ", 297 this->external_name(), target_host_class); 298 java_lang_Throwable::print(PENDING_EXCEPTION, &ss); 299 const char* msg = ss.as_string(true /* on C-heap */); 300 constantPoolHandle cph(THREAD, constants()); 301 SystemDictionary::add_nest_host_error(cph, _nest_host_index, msg); 302 CLEAR_PENDING_EXCEPTION; 303 304 log_trace(class, nestmates)("%s", msg); 305 } else { 306 // A valid nest-host is an instance class in the current package that lists this 307 // class as a nest member. If any of these conditions are not met the class is 308 // its own nest-host. 309 const char* error = nullptr; 310 311 // JVMS 5.4.4 indicates package check comes first 312 if (is_same_class_package(k)) { 313 // Now check actual membership. We can't be a member if our "host" is 314 // not an instance class. 315 if (k->is_instance_klass()) { 316 nest_host_k = InstanceKlass::cast(k); 317 bool is_member = nest_host_k->has_nest_member(THREAD, this); 318 if (is_member) { 319 _nest_host = nest_host_k; // save resolved nest-host value 320 321 log_trace(class, nestmates)("Resolved nest-host of %s to %s", 322 this->external_name(), k->external_name()); 323 return nest_host_k; 324 } else { 325 error = "current type is not listed as a nest member"; 326 } 327 } else { 328 error = "host is not an instance class"; 329 } 330 } else { 331 error = "types are in different packages"; 332 } 333 334 // something went wrong, so record what and log it 335 { 336 stringStream ss; 337 ss.print("Type %s (loader: %s) is not a nest member of type %s (loader: %s): %s", 338 this->external_name(), 339 this->class_loader_data()->loader_name_and_id(), 340 k->external_name(), 341 k->class_loader_data()->loader_name_and_id(), 342 error); 343 const char* msg = ss.as_string(true /* on C-heap */); 344 constantPoolHandle cph(THREAD, constants()); 345 SystemDictionary::add_nest_host_error(cph, _nest_host_index, msg); 346 log_trace(class, nestmates)("%s", msg); 347 } 348 } 349 } else { 350 log_trace(class, nestmates)("Type %s is not part of a nest: setting nest-host to self", 351 this->external_name()); 352 } 353 354 // Either not in an explicit nest, or else an error occurred, so 355 // the nest-host is set to `this`. Any thread that sees this assignment 356 // will also see any setting of nest_host_error(), if applicable. 357 return (_nest_host = this); 358 } 359 360 // Dynamic nest member support: set this class's nest host to the given class. 361 // This occurs as part of the class definition, as soon as the instanceKlass 362 // has been created and doesn't require further resolution. The code: 363 // lookup().defineHiddenClass(bytes_for_X, NESTMATE); 364 // results in: 365 // class_of_X.set_nest_host(lookup().lookupClass().getNestHost()) 366 // If it has an explicit _nest_host_index or _nest_members, these will be ignored. 367 // We also know the "host" is a valid nest-host in the same package so we can 368 // assert some of those facts. 369 void InstanceKlass::set_nest_host(InstanceKlass* host) { 370 assert(is_hidden(), "must be a hidden class"); 371 assert(host != nullptr, "null nest host specified"); 372 assert(_nest_host == nullptr, "current class has resolved nest-host"); 373 assert(nest_host_error() == nullptr, "unexpected nest host resolution error exists: %s", 374 nest_host_error()); 375 assert((host->_nest_host == nullptr && host->_nest_host_index == 0) || 376 (host->_nest_host == host), "proposed host is not a valid nest-host"); 377 // Can't assert this as package is not set yet: 378 // assert(is_same_class_package(host), "proposed host is in wrong package"); 379 380 if (log_is_enabled(Trace, class, nestmates)) { 381 ResourceMark rm; 382 const char* msg = ""; 383 // a hidden class does not expect a statically defined nest-host 384 if (_nest_host_index > 0) { 385 msg = "(the NestHost attribute in the current class is ignored)"; 386 } else if (_nest_members != nullptr && _nest_members != Universe::the_empty_short_array()) { 387 msg = "(the NestMembers attribute in the current class is ignored)"; 388 } 389 log_trace(class, nestmates)("Injected type %s into the nest of %s %s", 390 this->external_name(), 391 host->external_name(), 392 msg); 393 } 394 // set dynamic nest host 395 _nest_host = host; 396 // Record dependency to keep nest host from being unloaded before this class. 397 ClassLoaderData* this_key = class_loader_data(); 398 assert(this_key != nullptr, "sanity"); 399 this_key->record_dependency(host); 400 } 401 402 // check if 'this' and k are nestmates (same nest_host), or k is our nest_host, 403 // or we are k's nest_host - all of which is covered by comparing the two 404 // resolved_nest_hosts. 405 // Any exceptions (i.e. VMEs) are propagated. 406 bool InstanceKlass::has_nestmate_access_to(InstanceKlass* k, TRAPS) { 407 408 assert(this != k, "this should be handled by higher-level code"); 409 410 // Per JVMS 5.4.4 we first resolve and validate the current class, then 411 // the target class k. 412 413 InstanceKlass* cur_host = nest_host(CHECK_false); 414 if (cur_host == nullptr) { 415 return false; 416 } 417 418 Klass* k_nest_host = k->nest_host(CHECK_false); 419 if (k_nest_host == nullptr) { 420 return false; 421 } 422 423 bool access = (cur_host == k_nest_host); 424 425 ResourceMark rm(THREAD); 426 log_trace(class, nestmates)("Class %s does %shave nestmate access to %s", 427 this->external_name(), 428 access ? "" : "NOT ", 429 k->external_name()); 430 return access; 431 } 432 433 const char* InstanceKlass::nest_host_error() { 434 if (_nest_host_index == 0) { 435 return nullptr; 436 } else { 437 constantPoolHandle cph(Thread::current(), constants()); 438 return SystemDictionary::find_nest_host_error(cph, (int)_nest_host_index); 439 } 440 } 441 442 InstanceKlass* InstanceKlass::allocate_instance_klass(const ClassFileParser& parser, TRAPS) { 443 const int size = InstanceKlass::size(parser.vtable_size(), 444 parser.itable_size(), 445 nonstatic_oop_map_size(parser.total_oop_map_count()), 446 parser.is_interface(), 447 parser.has_inline_fields() ? parser.java_fields_count() : 0, 448 parser.is_inline_type()); 449 450 const Symbol* const class_name = parser.class_name(); 451 assert(class_name != nullptr, "invariant"); 452 ClassLoaderData* loader_data = parser.loader_data(); 453 assert(loader_data != nullptr, "invariant"); 454 455 InstanceKlass* ik; 456 457 // Allocation 458 if (parser.is_instance_ref_klass()) { 459 // java.lang.ref.Reference 460 ik = new (loader_data, size, THREAD) InstanceRefKlass(parser); 461 } else if (class_name == vmSymbols::java_lang_Class()) { 462 // mirror - java.lang.Class 463 ik = new (loader_data, size, THREAD) InstanceMirrorKlass(parser); 464 } else if (is_stack_chunk_class(class_name, loader_data)) { 465 // stack chunk 466 ik = new (loader_data, size, THREAD) InstanceStackChunkKlass(parser); 467 } else if (is_class_loader(class_name, parser)) { 468 // class loader - java.lang.ClassLoader 469 ik = new (loader_data, size, THREAD) InstanceClassLoaderKlass(parser); 470 } else if (parser.is_inline_type()) { 471 // inline type 472 ik = new (loader_data, size, THREAD) InlineKlass(parser); 473 } else { 474 // normal 475 ik = new (loader_data, size, THREAD) InstanceKlass(parser); 476 } 477 478 // Check for pending exception before adding to the loader data and incrementing 479 // class count. Can get OOM here. 480 if (HAS_PENDING_EXCEPTION) { 481 return nullptr; 482 } 483 484 #ifdef ASSERT 485 ik->bounds_check((address) ik->start_of_vtable(), false, size); 486 ik->bounds_check((address) ik->start_of_itable(), false, size); 487 ik->bounds_check((address) ik->end_of_itable(), true, size); 488 ik->bounds_check((address) ik->end_of_nonstatic_oop_maps(), true, size); 489 #endif //ASSERT 490 return ik; 491 } 492 493 #ifndef PRODUCT 494 bool InstanceKlass::bounds_check(address addr, bool edge_ok, intptr_t size_in_bytes) const { 495 const char* bad = nullptr; 496 address end = nullptr; 497 if (addr < (address)this) { 498 bad = "before"; 499 } else if (addr == (address)this) { 500 if (edge_ok) return true; 501 bad = "just before"; 502 } else if (addr == (end = (address)this + sizeof(intptr_t) * (size_in_bytes < 0 ? size() : size_in_bytes))) { 503 if (edge_ok) return true; 504 bad = "just after"; 505 } else if (addr > end) { 506 bad = "after"; 507 } else { 508 return true; 509 } 510 tty->print_cr("%s object bounds: " INTPTR_FORMAT " [" INTPTR_FORMAT ".." INTPTR_FORMAT "]", 511 bad, (intptr_t)addr, (intptr_t)this, (intptr_t)end); 512 Verbose = WizardMode = true; this->print(); //@@ 513 return false; 514 } 515 #endif //PRODUCT 516 517 // copy method ordering from resource area to Metaspace 518 void InstanceKlass::copy_method_ordering(const intArray* m, TRAPS) { 519 if (m != nullptr) { 520 // allocate a new array and copy contents (memcpy?) 521 _method_ordering = MetadataFactory::new_array<int>(class_loader_data(), m->length(), CHECK); 522 for (int i = 0; i < m->length(); i++) { 523 _method_ordering->at_put(i, m->at(i)); 524 } 525 } else { 526 _method_ordering = Universe::the_empty_int_array(); 527 } 528 } 529 530 // create a new array of vtable_indices for default methods 531 Array<int>* InstanceKlass::create_new_default_vtable_indices(int len, TRAPS) { 532 Array<int>* vtable_indices = MetadataFactory::new_array<int>(class_loader_data(), len, CHECK_NULL); 533 assert(default_vtable_indices() == nullptr, "only create once"); 534 set_default_vtable_indices(vtable_indices); 535 return vtable_indices; 536 } 537 538 static Monitor* create_init_monitor(const char* name) { 539 return new Monitor(Mutex::safepoint, name); 540 } 541 542 InstanceKlass::InstanceKlass(const ClassFileParser& parser, KlassKind kind, ReferenceType reference_type) : 543 Klass(kind), 544 _nest_members(nullptr), 545 _nest_host(nullptr), 546 _permitted_subclasses(nullptr), 547 _record_components(nullptr), 548 _static_field_size(parser.static_field_size()), 549 _nonstatic_oop_map_size(nonstatic_oop_map_size(parser.total_oop_map_count())), 550 _itable_len(parser.itable_size()), 551 _nest_host_index(0), 552 _init_state(allocated), 553 _reference_type(reference_type), 554 _init_monitor(create_init_monitor("InstanceKlassInitMonitor_lock")), 555 _init_thread(nullptr), 556 _inline_type_field_klasses(nullptr), 557 _preload_classes(nullptr), 558 _adr_inlineklass_fixed_block(nullptr) 559 { 560 set_vtable_length(parser.vtable_size()); 561 set_access_flags(parser.access_flags()); 562 if (parser.is_hidden()) set_is_hidden(); 563 set_layout_helper(Klass::instance_layout_helper(parser.layout_size(), 564 false)); 565 if (parser.has_inline_fields()) { 566 set_has_inline_type_fields(); 567 } 568 569 assert(nullptr == _methods, "underlying memory not zeroed?"); 570 assert(is_instance_klass(), "is layout incorrect?"); 571 assert(size_helper() == parser.layout_size(), "incorrect size_helper?"); 572 573 if (has_inline_type_fields()) { 574 _inline_type_field_klasses = (const Klass**) adr_inline_type_field_klasses(); 575 } 576 } 577 578 void InstanceKlass::deallocate_methods(ClassLoaderData* loader_data, 579 Array<Method*>* methods) { 580 if (methods != nullptr && methods != Universe::the_empty_method_array() && 581 !methods->is_shared()) { 582 for (int i = 0; i < methods->length(); i++) { 583 Method* method = methods->at(i); 584 if (method == nullptr) continue; // maybe null if error processing 585 // Only want to delete methods that are not executing for RedefineClasses. 586 // The previous version will point to them so they're not totally dangling 587 assert (!method->on_stack(), "shouldn't be called with methods on stack"); 588 MetadataFactory::free_metadata(loader_data, method); 589 } 590 MetadataFactory::free_array<Method*>(loader_data, methods); 591 } 592 } 593 594 void InstanceKlass::deallocate_interfaces(ClassLoaderData* loader_data, 595 const Klass* super_klass, 596 Array<InstanceKlass*>* local_interfaces, 597 Array<InstanceKlass*>* transitive_interfaces) { 598 // Only deallocate transitive interfaces if not empty, same as super class 599 // or same as local interfaces. See code in parseClassFile. 600 Array<InstanceKlass*>* ti = transitive_interfaces; 601 if (ti != Universe::the_empty_instance_klass_array() && ti != local_interfaces) { 602 // check that the interfaces don't come from super class 603 Array<InstanceKlass*>* sti = (super_klass == nullptr) ? nullptr : 604 InstanceKlass::cast(super_klass)->transitive_interfaces(); 605 if (ti != sti && ti != nullptr && !ti->is_shared()) { 606 MetadataFactory::free_array<InstanceKlass*>(loader_data, ti); 607 } 608 } 609 610 // local interfaces can be empty 611 if (local_interfaces != Universe::the_empty_instance_klass_array() && 612 local_interfaces != nullptr && !local_interfaces->is_shared()) { 613 MetadataFactory::free_array<InstanceKlass*>(loader_data, local_interfaces); 614 } 615 } 616 617 void InstanceKlass::deallocate_record_components(ClassLoaderData* loader_data, 618 Array<RecordComponent*>* record_components) { 619 if (record_components != nullptr && !record_components->is_shared()) { 620 for (int i = 0; i < record_components->length(); i++) { 621 RecordComponent* record_component = record_components->at(i); 622 MetadataFactory::free_metadata(loader_data, record_component); 623 } 624 MetadataFactory::free_array<RecordComponent*>(loader_data, record_components); 625 } 626 } 627 628 // This function deallocates the metadata and C heap pointers that the 629 // InstanceKlass points to. 630 void InstanceKlass::deallocate_contents(ClassLoaderData* loader_data) { 631 // Orphan the mirror first, CMS thinks it's still live. 632 if (java_mirror() != nullptr) { 633 java_lang_Class::set_klass(java_mirror(), nullptr); 634 } 635 636 // Also remove mirror from handles 637 loader_data->remove_handle(_java_mirror); 638 639 // Need to take this class off the class loader data list. 640 loader_data->remove_class(this); 641 642 // The array_klass for this class is created later, after error handling. 643 // For class redefinition, we keep the original class so this scratch class 644 // doesn't have an array class. Either way, assert that there is nothing 645 // to deallocate. 646 assert(array_klasses() == nullptr, "array classes shouldn't be created for this class yet"); 647 648 // Release C heap allocated data that this points to, which includes 649 // reference counting symbol names. 650 // Can't release the constant pool or MethodData C heap data here because the constant 651 // pool can be deallocated separately from the InstanceKlass for default methods and 652 // redefine classes. MethodData can also be released separately. 653 release_C_heap_structures(/* release_sub_metadata */ false); 654 655 deallocate_methods(loader_data, methods()); 656 set_methods(nullptr); 657 658 deallocate_record_components(loader_data, record_components()); 659 set_record_components(nullptr); 660 661 if (method_ordering() != nullptr && 662 method_ordering() != Universe::the_empty_int_array() && 663 !method_ordering()->is_shared()) { 664 MetadataFactory::free_array<int>(loader_data, method_ordering()); 665 } 666 set_method_ordering(nullptr); 667 668 // default methods can be empty 669 if (default_methods() != nullptr && 670 default_methods() != Universe::the_empty_method_array() && 671 !default_methods()->is_shared()) { 672 MetadataFactory::free_array<Method*>(loader_data, default_methods()); 673 } 674 // Do NOT deallocate the default methods, they are owned by superinterfaces. 675 set_default_methods(nullptr); 676 677 // default methods vtable indices can be empty 678 if (default_vtable_indices() != nullptr && 679 !default_vtable_indices()->is_shared()) { 680 MetadataFactory::free_array<int>(loader_data, default_vtable_indices()); 681 } 682 set_default_vtable_indices(nullptr); 683 684 685 // This array is in Klass, but remove it with the InstanceKlass since 686 // this place would be the only caller and it can share memory with transitive 687 // interfaces. 688 if (secondary_supers() != nullptr && 689 secondary_supers() != Universe::the_empty_klass_array() && 690 // see comments in compute_secondary_supers about the following cast 691 (address)(secondary_supers()) != (address)(transitive_interfaces()) && 692 !secondary_supers()->is_shared()) { 693 MetadataFactory::free_array<Klass*>(loader_data, secondary_supers()); 694 } 695 set_secondary_supers(nullptr); 696 697 deallocate_interfaces(loader_data, super(), local_interfaces(), transitive_interfaces()); 698 set_transitive_interfaces(nullptr); 699 set_local_interfaces(nullptr); 700 701 if (fieldinfo_stream() != nullptr && !fieldinfo_stream()->is_shared()) { 702 MetadataFactory::free_array<u1>(loader_data, fieldinfo_stream()); 703 } 704 set_fieldinfo_stream(nullptr); 705 706 if (fields_status() != nullptr && !fields_status()->is_shared()) { 707 MetadataFactory::free_array<FieldStatus>(loader_data, fields_status()); 708 } 709 set_fields_status(nullptr); 710 711 // If a method from a redefined class is using this constant pool, don't 712 // delete it, yet. The new class's previous version will point to this. 713 if (constants() != nullptr) { 714 assert (!constants()->on_stack(), "shouldn't be called if anything is onstack"); 715 if (!constants()->is_shared()) { 716 MetadataFactory::free_metadata(loader_data, constants()); 717 } 718 // Delete any cached resolution errors for the constant pool 719 SystemDictionary::delete_resolution_error(constants()); 720 721 set_constants(nullptr); 722 } 723 724 if (inner_classes() != nullptr && 725 inner_classes() != Universe::the_empty_short_array() && 726 !inner_classes()->is_shared()) { 727 MetadataFactory::free_array<jushort>(loader_data, inner_classes()); 728 } 729 set_inner_classes(nullptr); 730 731 if (nest_members() != nullptr && 732 nest_members() != Universe::the_empty_short_array() && 733 !nest_members()->is_shared()) { 734 MetadataFactory::free_array<jushort>(loader_data, nest_members()); 735 } 736 set_nest_members(nullptr); 737 738 if (permitted_subclasses() != nullptr && 739 permitted_subclasses() != Universe::the_empty_short_array() && 740 !permitted_subclasses()->is_shared()) { 741 MetadataFactory::free_array<jushort>(loader_data, permitted_subclasses()); 742 } 743 set_permitted_subclasses(nullptr); 744 745 if (preload_classes() != nullptr && 746 preload_classes() != Universe::the_empty_short_array() && 747 !preload_classes()->is_shared()) { 748 MetadataFactory::free_array<jushort>(loader_data, preload_classes()); 749 } 750 751 // We should deallocate the Annotations instance if it's not in shared spaces. 752 if (annotations() != nullptr && !annotations()->is_shared()) { 753 MetadataFactory::free_metadata(loader_data, annotations()); 754 } 755 set_annotations(nullptr); 756 757 SystemDictionaryShared::handle_class_unloading(this); 758 759 #if INCLUDE_CDS_JAVA_HEAP 760 if (DumpSharedSpaces) { 761 HeapShared::remove_scratch_objects(this); 762 } 763 #endif 764 } 765 766 bool InstanceKlass::is_record() const { 767 return _record_components != nullptr && 768 is_final() && 769 java_super() == vmClasses::Record_klass(); 770 } 771 772 bool InstanceKlass::is_sealed() const { 773 return _permitted_subclasses != nullptr && 774 _permitted_subclasses != Universe::the_empty_short_array(); 775 } 776 777 bool InstanceKlass::should_be_initialized() const { 778 return !is_initialized(); 779 } 780 781 klassItable InstanceKlass::itable() const { 782 return klassItable(const_cast<InstanceKlass*>(this)); 783 } 784 785 // JVMTI spec thinks there are signers and protection domain in the 786 // instanceKlass. These accessors pretend these fields are there. 787 // The hprof specification also thinks these fields are in InstanceKlass. 788 oop InstanceKlass::protection_domain() const { 789 // return the protection_domain from the mirror 790 return java_lang_Class::protection_domain(java_mirror()); 791 } 792 793 objArrayOop InstanceKlass::signers() const { 794 // return the signers from the mirror 795 return java_lang_Class::signers(java_mirror()); 796 } 797 798 // See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization 799 // process. The step comments refers to the procedure described in that section. 800 // Note: implementation moved to static method to expose the this pointer. 801 void InstanceKlass::initialize(TRAPS) { 802 if (this->should_be_initialized()) { 803 initialize_impl(CHECK); 804 // Note: at this point the class may be initialized 805 // OR it may be in the state of being initialized 806 // in case of recursive initialization! 807 } else { 808 assert(is_initialized(), "sanity check"); 809 } 810 } 811 812 813 bool InstanceKlass::verify_code(TRAPS) { 814 // 1) Verify the bytecodes 815 return Verifier::verify(this, should_verify_class(), THREAD); 816 } 817 818 void InstanceKlass::link_class(TRAPS) { 819 assert(is_loaded(), "must be loaded"); 820 if (!is_linked()) { 821 link_class_impl(CHECK); 822 } 823 } 824 825 void InstanceKlass::check_link_state_and_wait(JavaThread* current) { 826 MonitorLocker ml(current, _init_monitor); 827 828 // Another thread is linking this class, wait. 829 while (is_being_linked() && !is_init_thread(current)) { 830 ml.wait(); 831 } 832 833 // This thread is recursively linking this class, continue 834 if (is_being_linked() && is_init_thread(current)) { 835 return; 836 } 837 838 // If this class wasn't linked already, set state to being_linked 839 if (!is_linked()) { 840 set_init_state(being_linked); 841 set_init_thread(current); 842 } 843 } 844 845 // Called to verify that a class can link during initialization, without 846 // throwing a VerifyError. 847 bool InstanceKlass::link_class_or_fail(TRAPS) { 848 assert(is_loaded(), "must be loaded"); 849 if (!is_linked()) { 850 link_class_impl(CHECK_false); 851 } 852 return is_linked(); 853 } 854 855 bool InstanceKlass::link_class_impl(TRAPS) { 856 if (DumpSharedSpaces && SystemDictionaryShared::has_class_failed_verification(this)) { 857 // This is for CDS dumping phase only -- we use the in_error_state to indicate that 858 // the class has failed verification. Throwing the NoClassDefFoundError here is just 859 // a convenient way to stop repeat attempts to verify the same (bad) class. 860 // 861 // Note that the NoClassDefFoundError is not part of the JLS, and should not be thrown 862 // if we are executing Java code. This is not a problem for CDS dumping phase since 863 // it doesn't execute any Java code. 864 ResourceMark rm(THREAD); 865 Exceptions::fthrow(THREAD_AND_LOCATION, 866 vmSymbols::java_lang_NoClassDefFoundError(), 867 "Class %s, or one of its supertypes, failed class initialization", 868 external_name()); 869 return false; 870 } 871 // return if already verified 872 if (is_linked()) { 873 return true; 874 } 875 876 // Timing 877 // timer handles recursion 878 JavaThread* jt = THREAD; 879 880 // link super class before linking this class 881 Klass* super_klass = super(); 882 if (super_klass != nullptr) { 883 if (super_klass->is_interface()) { // check if super class is an interface 884 ResourceMark rm(THREAD); 885 Exceptions::fthrow( 886 THREAD_AND_LOCATION, 887 vmSymbols::java_lang_IncompatibleClassChangeError(), 888 "class %s has interface %s as super class", 889 external_name(), 890 super_klass->external_name() 891 ); 892 return false; 893 } 894 895 InstanceKlass* ik_super = InstanceKlass::cast(super_klass); 896 ik_super->link_class_impl(CHECK_false); 897 } 898 899 // link all interfaces implemented by this class before linking this class 900 Array<InstanceKlass*>* interfaces = local_interfaces(); 901 int num_interfaces = interfaces->length(); 902 for (int index = 0; index < num_interfaces; index++) { 903 InstanceKlass* interk = interfaces->at(index); 904 interk->link_class_impl(CHECK_false); 905 } 906 907 908 // If a class declares a method that uses an inline class as an argument 909 // type or return inline type, this inline class must be loaded during the 910 // linking of this class because size and properties of the inline class 911 // must be known in order to be able to perform inline type optimizations. 912 // The implementation below is an approximation of this rule, the code 913 // iterates over all methods of the current class (including overridden 914 // methods), not only the methods declared by this class. This 915 // approximation makes the code simpler, and doesn't change the semantic 916 // because classes declaring methods overridden by the current class are 917 // linked (and have performed their own pre-loading) before the linking 918 // of the current class. 919 920 921 // Note: 922 // Inline class types are loaded during 923 // the loading phase (see ClassFileParser::post_process_parsed_stream()). 924 // Inline class types used as element types for array creation 925 // are not pre-loaded. Their loading is triggered by either anewarray 926 // or multianewarray bytecodes. 927 928 // Could it be possible to do the following processing only if the 929 // class uses inline types? 930 if (EnableValhalla) { 931 ResourceMark rm(THREAD); 932 if (EnablePrimitiveClasses) { 933 for (int i = 0; i < methods()->length(); i++) { 934 Method* m = methods()->at(i); 935 for (SignatureStream ss(m->signature()); !ss.is_done(); ss.next()) { 936 if (ss.is_reference()) { 937 if (ss.is_array()) { 938 continue; 939 } 940 if (ss.type() == T_PRIMITIVE_OBJECT) { 941 Symbol* symb = ss.as_symbol(); 942 if (symb == name()) continue; 943 oop loader = class_loader(); 944 oop protection_domain = this->protection_domain(); 945 Klass* klass = SystemDictionary::resolve_or_fail(symb, 946 Handle(THREAD, loader), Handle(THREAD, protection_domain), true, 947 CHECK_false); 948 if (klass == nullptr) { 949 THROW_(vmSymbols::java_lang_LinkageError(), false); 950 } 951 if (!klass->is_inline_klass()) { 952 Exceptions::fthrow( 953 THREAD_AND_LOCATION, 954 vmSymbols::java_lang_IncompatibleClassChangeError(), 955 "class %s is not an inline type", 956 klass->external_name()); 957 } 958 } 959 } 960 } 961 } 962 } 963 // Aggressively preloading all classes from the Preload attribute 964 if (preload_classes() != nullptr) { 965 for (int i = 0; i < preload_classes()->length(); i++) { 966 if (constants()->tag_at(preload_classes()->at(i)).is_klass()) continue; 967 Symbol* class_name = constants()->klass_at_noresolve(preload_classes()->at(i)); 968 if (class_name == name()) continue; 969 oop loader = class_loader(); 970 oop protection_domain = this->protection_domain(); 971 Klass* klass = SystemDictionary::resolve_or_null(class_name, 972 Handle(THREAD, loader), Handle(THREAD, protection_domain), THREAD); 973 if (HAS_PENDING_EXCEPTION) { 974 CLEAR_PENDING_EXCEPTION; 975 } 976 if (klass != nullptr) { 977 log_info(class, preload)("Preloading class %s during linking of class %s because of its Preload attribute", class_name->as_C_string(), name()->as_C_string()); 978 } else { 979 log_warning(class, preload)("Preloading of class %s during linking of class %s (Preload attribute) failed", class_name->as_C_string(), name()->as_C_string()); 980 } 981 } 982 } 983 } 984 985 // in case the class is linked in the process of linking its superclasses 986 if (is_linked()) { 987 return true; 988 } 989 990 // trace only the link time for this klass that includes 991 // the verification time 992 PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(), 993 ClassLoader::perf_class_link_selftime(), 994 ClassLoader::perf_classes_linked(), 995 jt->get_thread_stat()->perf_recursion_counts_addr(), 996 jt->get_thread_stat()->perf_timers_addr(), 997 PerfClassTraceTime::CLASS_LINK); 998 999 // verification & rewriting 1000 { 1001 LockLinkState init_lock(this, jt); 1002 1003 // rewritten will have been set if loader constraint error found 1004 // on an earlier link attempt 1005 // don't verify or rewrite if already rewritten 1006 // 1007 1008 if (!is_linked()) { 1009 if (!is_rewritten()) { 1010 if (is_shared()) { 1011 assert(!verified_at_dump_time(), "must be"); 1012 } 1013 { 1014 bool verify_ok = verify_code(THREAD); 1015 if (!verify_ok) { 1016 return false; 1017 } 1018 } 1019 1020 // Just in case a side-effect of verify linked this class already 1021 // (which can sometimes happen since the verifier loads classes 1022 // using custom class loaders, which are free to initialize things) 1023 if (is_linked()) { 1024 return true; 1025 } 1026 1027 // also sets rewritten 1028 rewrite_class(CHECK_false); 1029 } else if (is_shared()) { 1030 SystemDictionaryShared::check_verification_constraints(this, CHECK_false); 1031 } 1032 1033 // relocate jsrs and link methods after they are all rewritten 1034 link_methods(CHECK_false); 1035 1036 // Initialize the vtable and interface table after 1037 // methods have been rewritten since rewrite may 1038 // fabricate new Method*s. 1039 // also does loader constraint checking 1040 // 1041 // initialize_vtable and initialize_itable need to be rerun 1042 // for a shared class if 1043 // 1) the class is loaded by custom class loader or 1044 // 2) the class is loaded by built-in class loader but failed to add archived loader constraints or 1045 // 3) the class was not verified during dump time 1046 bool need_init_table = true; 1047 if (is_shared() && verified_at_dump_time() && 1048 SystemDictionaryShared::check_linking_constraints(THREAD, this)) { 1049 need_init_table = false; 1050 } 1051 if (need_init_table) { 1052 vtable().initialize_vtable_and_check_constraints(CHECK_false); 1053 itable().initialize_itable_and_check_constraints(CHECK_false); 1054 } 1055 #ifdef ASSERT 1056 vtable().verify(tty, true); 1057 // In case itable verification is ever added. 1058 // itable().verify(tty, true); 1059 #endif 1060 set_initialization_state_and_notify(linked, THREAD); 1061 if (JvmtiExport::should_post_class_prepare()) { 1062 JvmtiExport::post_class_prepare(THREAD, this); 1063 } 1064 } 1065 } 1066 return true; 1067 } 1068 1069 // Rewrite the byte codes of all of the methods of a class. 1070 // The rewriter must be called exactly once. Rewriting must happen after 1071 // verification but before the first method of the class is executed. 1072 void InstanceKlass::rewrite_class(TRAPS) { 1073 assert(is_loaded(), "must be loaded"); 1074 if (is_rewritten()) { 1075 assert(is_shared(), "rewriting an unshared class?"); 1076 return; 1077 } 1078 Rewriter::rewrite(this, CHECK); 1079 set_rewritten(); 1080 } 1081 1082 // Now relocate and link method entry points after class is rewritten. 1083 // This is outside is_rewritten flag. In case of an exception, it can be 1084 // executed more than once. 1085 void InstanceKlass::link_methods(TRAPS) { 1086 int len = methods()->length(); 1087 for (int i = len-1; i >= 0; i--) { 1088 methodHandle m(THREAD, methods()->at(i)); 1089 1090 // Set up method entry points for compiler and interpreter . 1091 m->link_method(m, CHECK); 1092 } 1093 } 1094 1095 // Eagerly initialize superinterfaces that declare default methods (concrete instance: any access) 1096 void InstanceKlass::initialize_super_interfaces(TRAPS) { 1097 assert (has_nonstatic_concrete_methods(), "caller should have checked this"); 1098 for (int i = 0; i < local_interfaces()->length(); ++i) { 1099 InstanceKlass* ik = local_interfaces()->at(i); 1100 1101 // Initialization is depth first search ie. we start with top of the inheritance tree 1102 // has_nonstatic_concrete_methods drives searching superinterfaces since it 1103 // means has_nonstatic_concrete_methods in its superinterface hierarchy 1104 if (ik->has_nonstatic_concrete_methods()) { 1105 ik->initialize_super_interfaces(CHECK); 1106 } 1107 1108 // Only initialize() interfaces that "declare" concrete methods. 1109 if (ik->should_be_initialized() && ik->declares_nonstatic_concrete_methods()) { 1110 ik->initialize(CHECK); 1111 } 1112 } 1113 } 1114 1115 using InitializationErrorTable = ResourceHashtable<const InstanceKlass*, OopHandle, 107, AnyObj::C_HEAP, mtClass>; 1116 static InitializationErrorTable* _initialization_error_table; 1117 1118 void InstanceKlass::add_initialization_error(JavaThread* current, Handle exception) { 1119 // Create the same exception with a message indicating the thread name, 1120 // and the StackTraceElements. 1121 Handle init_error = java_lang_Throwable::create_initialization_error(current, exception); 1122 ResourceMark rm(current); 1123 if (init_error.is_null()) { 1124 log_trace(class, init)("Unable to create the desired initialization error for class %s", external_name()); 1125 1126 // We failed to create the new exception, most likely due to either out-of-memory or 1127 // a stackoverflow error. If the original exception was either of those then we save 1128 // the shared, pre-allocated, stackless, instance of that exception. 1129 if (exception->klass() == vmClasses::StackOverflowError_klass()) { 1130 log_debug(class, init)("Using shared StackOverflowError as initialization error for class %s", external_name()); 1131 init_error = Handle(current, Universe::class_init_stack_overflow_error()); 1132 } else if (exception->klass() == vmClasses::OutOfMemoryError_klass()) { 1133 log_debug(class, init)("Using shared OutOfMemoryError as initialization error for class %s", external_name()); 1134 init_error = Handle(current, Universe::class_init_out_of_memory_error()); 1135 } else { 1136 return; 1137 } 1138 } 1139 1140 MutexLocker ml(current, ClassInitError_lock); 1141 OopHandle elem = OopHandle(Universe::vm_global(), init_error()); 1142 bool created; 1143 if (_initialization_error_table == nullptr) { 1144 _initialization_error_table = new (mtClass) InitializationErrorTable(); 1145 } 1146 _initialization_error_table->put_if_absent(this, elem, &created); 1147 assert(created, "Initialization is single threaded"); 1148 log_trace(class, init)("Initialization error added for class %s", external_name()); 1149 } 1150 1151 oop InstanceKlass::get_initialization_error(JavaThread* current) { 1152 MutexLocker ml(current, ClassInitError_lock); 1153 if (_initialization_error_table == nullptr) { 1154 return nullptr; 1155 } 1156 OopHandle* h = _initialization_error_table->get(this); 1157 return (h != nullptr) ? h->resolve() : nullptr; 1158 } 1159 1160 // Need to remove entries for unloaded classes. 1161 void InstanceKlass::clean_initialization_error_table() { 1162 struct InitErrorTableCleaner { 1163 bool do_entry(const InstanceKlass* ik, OopHandle h) { 1164 if (!ik->is_loader_alive()) { 1165 h.release(Universe::vm_global()); 1166 return true; 1167 } else { 1168 return false; 1169 } 1170 } 1171 }; 1172 1173 assert_locked_or_safepoint(ClassInitError_lock); 1174 InitErrorTableCleaner cleaner; 1175 if (_initialization_error_table != nullptr) { 1176 _initialization_error_table->unlink(&cleaner); 1177 } 1178 } 1179 1180 void InstanceKlass::initialize_impl(TRAPS) { 1181 HandleMark hm(THREAD); 1182 1183 // Make sure klass is linked (verified) before initialization 1184 // A class could already be verified, since it has been reflected upon. 1185 link_class(CHECK); 1186 1187 DTRACE_CLASSINIT_PROBE(required, -1); 1188 1189 bool wait = false; 1190 bool throw_error = false; 1191 1192 JavaThread* jt = THREAD; 1193 1194 // refer to the JVM book page 47 for description of steps 1195 // Step 1 1196 { 1197 MonitorLocker ml(THREAD, _init_monitor); 1198 1199 // Step 2 1200 while (is_being_initialized() && !is_init_thread(jt)) { 1201 wait = true; 1202 jt->set_class_to_be_initialized(this); 1203 ml.wait(); 1204 jt->set_class_to_be_initialized(nullptr); 1205 } 1206 1207 // Step 3 1208 if (is_being_initialized() && is_init_thread(jt)) { 1209 DTRACE_CLASSINIT_PROBE_WAIT(recursive, -1, wait); 1210 return; 1211 } 1212 1213 // Step 4 1214 if (is_initialized()) { 1215 DTRACE_CLASSINIT_PROBE_WAIT(concurrent, -1, wait); 1216 return; 1217 } 1218 1219 // Step 5 1220 if (is_in_error_state()) { 1221 throw_error = true; 1222 } else { 1223 1224 // Step 6 1225 set_init_state(being_initialized); 1226 set_init_thread(jt); 1227 } 1228 } 1229 1230 // Throw error outside lock 1231 if (throw_error) { 1232 DTRACE_CLASSINIT_PROBE_WAIT(erroneous, -1, wait); 1233 ResourceMark rm(THREAD); 1234 Handle cause(THREAD, get_initialization_error(THREAD)); 1235 1236 stringStream ss; 1237 ss.print("Could not initialize class %s", external_name()); 1238 if (cause.is_null()) { 1239 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), ss.as_string()); 1240 } else { 1241 THROW_MSG_CAUSE(vmSymbols::java_lang_NoClassDefFoundError(), 1242 ss.as_string(), cause); 1243 } 1244 } 1245 1246 // Pre-allocating an instance of the default value 1247 if (is_inline_klass()) { 1248 InlineKlass* vk = InlineKlass::cast(this); 1249 oop val = vk->allocate_instance(THREAD); 1250 if (HAS_PENDING_EXCEPTION) { 1251 Handle e(THREAD, PENDING_EXCEPTION); 1252 CLEAR_PENDING_EXCEPTION; 1253 { 1254 EXCEPTION_MARK; 1255 add_initialization_error(THREAD, e); 1256 // Locks object, set state, and notify all waiting threads 1257 set_initialization_state_and_notify(initialization_error, THREAD); 1258 CLEAR_PENDING_EXCEPTION; 1259 } 1260 THROW_OOP(e()); 1261 } 1262 vk->set_default_value(val); 1263 } 1264 1265 // Step 7 1266 // Next, if C is a class rather than an interface, initialize it's super class and super 1267 // interfaces. 1268 if (!is_interface()) { 1269 Klass* super_klass = super(); 1270 if (super_klass != nullptr && super_klass->should_be_initialized()) { 1271 super_klass->initialize(THREAD); 1272 } 1273 // If C implements any interface that declares a non-static, concrete method, 1274 // the initialization of C triggers initialization of its super interfaces. 1275 // Only need to recurse if has_nonstatic_concrete_methods which includes declaring and 1276 // having a superinterface that declares, non-static, concrete methods 1277 if (!HAS_PENDING_EXCEPTION && has_nonstatic_concrete_methods()) { 1278 initialize_super_interfaces(THREAD); 1279 } 1280 1281 // If any exceptions, complete abruptly, throwing the same exception as above. 1282 if (HAS_PENDING_EXCEPTION) { 1283 Handle e(THREAD, PENDING_EXCEPTION); 1284 CLEAR_PENDING_EXCEPTION; 1285 { 1286 EXCEPTION_MARK; 1287 add_initialization_error(THREAD, e); 1288 // Locks object, set state, and notify all waiting threads 1289 set_initialization_state_and_notify(initialization_error, THREAD); 1290 CLEAR_PENDING_EXCEPTION; 1291 } 1292 DTRACE_CLASSINIT_PROBE_WAIT(super__failed, -1, wait); 1293 THROW_OOP(e()); 1294 } 1295 } 1296 1297 // Step 8 1298 // Initialize classes of inline fields 1299 if (EnablePrimitiveClasses) { 1300 for (AllFieldStream fs(this); !fs.done(); fs.next()) { 1301 if (fs.is_null_free_inline_type()) { 1302 Klass* klass = get_inline_type_field_klass_or_null(fs.index()); 1303 if (fs.access_flags().is_static() && klass == nullptr) { 1304 klass = SystemDictionary::resolve_or_fail(field_signature(fs.index())->fundamental_name(THREAD), 1305 Handle(THREAD, class_loader()), 1306 Handle(THREAD, protection_domain()), 1307 true, THREAD); 1308 set_inline_type_field_klass(fs.index(), klass); 1309 } 1310 1311 if (!HAS_PENDING_EXCEPTION) { 1312 assert(klass != nullptr, "Must be"); 1313 InstanceKlass::cast(klass)->initialize(THREAD); 1314 if (fs.access_flags().is_static()) { 1315 if (java_mirror()->obj_field(fs.offset()) == nullptr) { 1316 java_mirror()->obj_field_put(fs.offset(), InlineKlass::cast(klass)->default_value()); 1317 } 1318 } 1319 } 1320 1321 if (HAS_PENDING_EXCEPTION) { 1322 Handle e(THREAD, PENDING_EXCEPTION); 1323 CLEAR_PENDING_EXCEPTION; 1324 { 1325 EXCEPTION_MARK; 1326 add_initialization_error(THREAD, e); 1327 // Locks object, set state, and notify all waiting threads 1328 set_initialization_state_and_notify(initialization_error, THREAD); 1329 CLEAR_PENDING_EXCEPTION; 1330 } 1331 THROW_OOP(e()); 1332 } 1333 } 1334 } 1335 } 1336 1337 1338 // Step 9 1339 { 1340 DTRACE_CLASSINIT_PROBE_WAIT(clinit, -1, wait); 1341 if (class_initializer() != nullptr) { 1342 // Timer includes any side effects of class initialization (resolution, 1343 // etc), but not recursive entry into call_class_initializer(). 1344 PerfClassTraceTime timer(ClassLoader::perf_class_init_time(), 1345 ClassLoader::perf_class_init_selftime(), 1346 ClassLoader::perf_classes_inited(), 1347 jt->get_thread_stat()->perf_recursion_counts_addr(), 1348 jt->get_thread_stat()->perf_timers_addr(), 1349 PerfClassTraceTime::CLASS_CLINIT); 1350 call_class_initializer(THREAD); 1351 } else { 1352 // The elapsed time is so small it's not worth counting. 1353 if (UsePerfData) { 1354 ClassLoader::perf_classes_inited()->inc(); 1355 } 1356 call_class_initializer(THREAD); 1357 } 1358 } 1359 1360 // Step 10 1361 if (!HAS_PENDING_EXCEPTION) { 1362 set_initialization_state_and_notify(fully_initialized, THREAD); 1363 debug_only(vtable().verify(tty, true);) 1364 } 1365 else { 1366 // Step 11 and 12 1367 Handle e(THREAD, PENDING_EXCEPTION); 1368 CLEAR_PENDING_EXCEPTION; 1369 // JVMTI has already reported the pending exception 1370 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError 1371 JvmtiExport::clear_detected_exception(jt); 1372 { 1373 EXCEPTION_MARK; 1374 add_initialization_error(THREAD, e); 1375 set_initialization_state_and_notify(initialization_error, THREAD); 1376 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, class initialization error is thrown below 1377 // JVMTI has already reported the pending exception 1378 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError 1379 JvmtiExport::clear_detected_exception(jt); 1380 } 1381 DTRACE_CLASSINIT_PROBE_WAIT(error, -1, wait); 1382 if (e->is_a(vmClasses::Error_klass())) { 1383 THROW_OOP(e()); 1384 } else { 1385 JavaCallArguments args(e); 1386 THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(), 1387 vmSymbols::throwable_void_signature(), 1388 &args); 1389 } 1390 } 1391 DTRACE_CLASSINIT_PROBE_WAIT(end, -1, wait); 1392 } 1393 1394 1395 void InstanceKlass::set_initialization_state_and_notify(ClassState state, JavaThread* current) { 1396 MonitorLocker ml(current, _init_monitor); 1397 1398 if (state == linked && UseVtableBasedCHA && Universe::is_fully_initialized()) { 1399 DeoptimizationScope deopt_scope; 1400 { 1401 // Now mark all code that assumes the class is not linked. 1402 // Set state under the Compile_lock also. 1403 MutexLocker ml(current, Compile_lock); 1404 1405 set_init_thread(nullptr); // reset _init_thread before changing _init_state 1406 set_init_state(state); 1407 1408 CodeCache::mark_dependents_on(&deopt_scope, this); 1409 } 1410 // Perform the deopt handshake outside Compile_lock. 1411 deopt_scope.deoptimize_marked(); 1412 } else { 1413 set_init_thread(nullptr); // reset _init_thread before changing _init_state 1414 set_init_state(state); 1415 } 1416 ml.notify_all(); 1417 } 1418 1419 // Update hierarchy. This is done before the new klass has been added to the SystemDictionary. The Compile_lock 1420 // is grabbed, to ensure that the compiler is not using the class hierarchy. 1421 void InstanceKlass::add_to_hierarchy(JavaThread* current) { 1422 assert(!SafepointSynchronize::is_at_safepoint(), "must NOT be at safepoint"); 1423 1424 // In case we are not using CHA based vtables we need to make sure the loaded 1425 // deopt is completed before anyone links this class. 1426 // Linking is done with _init_monitor held, by loading and deopting with it 1427 // held we make sure the deopt is completed before linking. 1428 if (!UseVtableBasedCHA) { 1429 init_monitor()->lock(); 1430 } 1431 1432 DeoptimizationScope deopt_scope; 1433 { 1434 MutexLocker ml(current, Compile_lock); 1435 1436 set_init_state(InstanceKlass::loaded); 1437 // make sure init_state store is already done. 1438 // The compiler reads the hierarchy outside of the Compile_lock. 1439 // Access ordering is used to add to hierarchy. 1440 1441 // Link into hierarchy. 1442 append_to_sibling_list(); // add to superklass/sibling list 1443 process_interfaces(); // handle all "implements" declarations 1444 1445 // Now mark all code that depended on old class hierarchy. 1446 // Note: must be done *after* linking k into the hierarchy (was bug 12/9/97) 1447 if (Universe::is_fully_initialized()) { 1448 CodeCache::mark_dependents_on(&deopt_scope, this); 1449 } 1450 } 1451 // Perform the deopt handshake outside Compile_lock. 1452 deopt_scope.deoptimize_marked(); 1453 1454 if (!UseVtableBasedCHA) { 1455 init_monitor()->unlock(); 1456 } 1457 } 1458 1459 InstanceKlass* InstanceKlass::implementor() const { 1460 InstanceKlass* volatile* ik = adr_implementor(); 1461 if (ik == nullptr) { 1462 return nullptr; 1463 } else { 1464 // This load races with inserts, and therefore needs acquire. 1465 InstanceKlass* ikls = Atomic::load_acquire(ik); 1466 if (ikls != nullptr && !ikls->is_loader_alive()) { 1467 return nullptr; // don't return unloaded class 1468 } else { 1469 return ikls; 1470 } 1471 } 1472 } 1473 1474 1475 void InstanceKlass::set_implementor(InstanceKlass* ik) { 1476 assert_locked_or_safepoint(Compile_lock); 1477 assert(is_interface(), "not interface"); 1478 InstanceKlass* volatile* addr = adr_implementor(); 1479 assert(addr != nullptr, "null addr"); 1480 if (addr != nullptr) { 1481 Atomic::release_store(addr, ik); 1482 } 1483 } 1484 1485 int InstanceKlass::nof_implementors() const { 1486 InstanceKlass* ik = implementor(); 1487 if (ik == nullptr) { 1488 return 0; 1489 } else if (ik != this) { 1490 return 1; 1491 } else { 1492 return 2; 1493 } 1494 } 1495 1496 // The embedded _implementor field can only record one implementor. 1497 // When there are more than one implementors, the _implementor field 1498 // is set to the interface Klass* itself. Following are the possible 1499 // values for the _implementor field: 1500 // null - no implementor 1501 // implementor Klass* - one implementor 1502 // self - more than one implementor 1503 // 1504 // The _implementor field only exists for interfaces. 1505 void InstanceKlass::add_implementor(InstanceKlass* ik) { 1506 if (Universe::is_fully_initialized()) { 1507 assert_lock_strong(Compile_lock); 1508 } 1509 assert(is_interface(), "not interface"); 1510 // Filter out my subinterfaces. 1511 // (Note: Interfaces are never on the subklass list.) 1512 if (ik->is_interface()) return; 1513 1514 // Filter out subclasses whose supers already implement me. 1515 // (Note: CHA must walk subclasses of direct implementors 1516 // in order to locate indirect implementors.) 1517 InstanceKlass* super_ik = ik->java_super(); 1518 if (super_ik != nullptr && super_ik->implements_interface(this)) 1519 // We only need to check one immediate superclass, since the 1520 // implements_interface query looks at transitive_interfaces. 1521 // Any supers of the super have the same (or fewer) transitive_interfaces. 1522 return; 1523 1524 InstanceKlass* iklass = implementor(); 1525 if (iklass == nullptr) { 1526 set_implementor(ik); 1527 } else if (iklass != this && iklass != ik) { 1528 // There is already an implementor. Use itself as an indicator of 1529 // more than one implementors. 1530 set_implementor(this); 1531 } 1532 1533 // The implementor also implements the transitive_interfaces 1534 for (int index = 0; index < local_interfaces()->length(); index++) { 1535 local_interfaces()->at(index)->add_implementor(ik); 1536 } 1537 } 1538 1539 void InstanceKlass::init_implementor() { 1540 if (is_interface()) { 1541 set_implementor(nullptr); 1542 } 1543 } 1544 1545 1546 void InstanceKlass::process_interfaces() { 1547 // link this class into the implementors list of every interface it implements 1548 for (int i = local_interfaces()->length() - 1; i >= 0; i--) { 1549 assert(local_interfaces()->at(i)->is_klass(), "must be a klass"); 1550 InstanceKlass* interf = local_interfaces()->at(i); 1551 assert(interf->is_interface(), "expected interface"); 1552 interf->add_implementor(this); 1553 } 1554 } 1555 1556 bool InstanceKlass::can_be_primary_super_slow() const { 1557 if (is_interface()) 1558 return false; 1559 else 1560 return Klass::can_be_primary_super_slow(); 1561 } 1562 1563 GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots, 1564 Array<InstanceKlass*>* transitive_interfaces) { 1565 // The secondaries are the implemented interfaces. 1566 Array<InstanceKlass*>* interfaces = transitive_interfaces; 1567 int num_secondaries = num_extra_slots + interfaces->length(); 1568 if (num_secondaries == 0) { 1569 // Must share this for correct bootstrapping! 1570 set_secondary_supers(Universe::the_empty_klass_array()); 1571 return nullptr; 1572 } else if (num_extra_slots == 0) { 1573 // The secondary super list is exactly the same as the transitive interfaces, so 1574 // let's use it instead of making a copy. 1575 // Redefine classes has to be careful not to delete this! 1576 // We need the cast because Array<Klass*> is NOT a supertype of Array<InstanceKlass*>, 1577 // (but it's safe to do here because we won't write into _secondary_supers from this point on). 1578 set_secondary_supers((Array<Klass*>*)(address)interfaces); 1579 return nullptr; 1580 } else { 1581 // Copy transitive interfaces to a temporary growable array to be constructed 1582 // into the secondary super list with extra slots. 1583 GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length()); 1584 for (int i = 0; i < interfaces->length(); i++) { 1585 secondaries->push(interfaces->at(i)); 1586 } 1587 return secondaries; 1588 } 1589 } 1590 1591 bool InstanceKlass::implements_interface(Klass* k) const { 1592 if (this == k) return true; 1593 assert(k->is_interface(), "should be an interface class"); 1594 for (int i = 0; i < transitive_interfaces()->length(); i++) { 1595 if (transitive_interfaces()->at(i) == k) { 1596 return true; 1597 } 1598 } 1599 return false; 1600 } 1601 1602 bool InstanceKlass::is_same_or_direct_interface(Klass *k) const { 1603 // Verify direct super interface 1604 if (this == k) return true; 1605 assert(k->is_interface(), "should be an interface class"); 1606 for (int i = 0; i < local_interfaces()->length(); i++) { 1607 if (local_interfaces()->at(i) == k) { 1608 return true; 1609 } 1610 } 1611 return false; 1612 } 1613 1614 objArrayOop InstanceKlass::allocate_objArray(int n, int length, TRAPS) { 1615 check_array_allocation_length(length, arrayOopDesc::max_array_length(T_OBJECT), CHECK_NULL); 1616 size_t size = objArrayOopDesc::object_size(length); 1617 Klass* ak = array_klass(n, CHECK_NULL); 1618 objArrayOop o = (objArrayOop)Universe::heap()->array_allocate(ak, size, length, 1619 /* do_zero */ true, CHECK_NULL); 1620 return o; 1621 } 1622 1623 instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) { 1624 if (TraceFinalizerRegistration) { 1625 tty->print("Registered "); 1626 i->print_value_on(tty); 1627 tty->print_cr(" (" PTR_FORMAT ") as finalizable", p2i(i)); 1628 } 1629 instanceHandle h_i(THREAD, i); 1630 // Pass the handle as argument, JavaCalls::call expects oop as jobjects 1631 JavaValue result(T_VOID); 1632 JavaCallArguments args(h_i); 1633 methodHandle mh(THREAD, Universe::finalizer_register_method()); 1634 JavaCalls::call(&result, mh, &args, CHECK_NULL); 1635 MANAGEMENT_ONLY(FinalizerService::on_register(h_i(), THREAD);) 1636 return h_i(); 1637 } 1638 1639 instanceOop InstanceKlass::allocate_instance(TRAPS) { 1640 bool has_finalizer_flag = has_finalizer(); // Query before possible GC 1641 size_t size = size_helper(); // Query before forming handle. 1642 1643 instanceOop i; 1644 1645 i = (instanceOop)Universe::heap()->obj_allocate(this, size, CHECK_NULL); 1646 if (has_finalizer_flag && !RegisterFinalizersAtInit) { 1647 i = register_finalizer(i, CHECK_NULL); 1648 } 1649 return i; 1650 } 1651 1652 instanceOop InstanceKlass::allocate_instance(oop java_class, TRAPS) { 1653 Klass* k = java_lang_Class::as_Klass(java_class); 1654 if (k == nullptr) { 1655 ResourceMark rm(THREAD); 1656 THROW_(vmSymbols::java_lang_InstantiationException(), nullptr); 1657 } 1658 InstanceKlass* ik = cast(k); 1659 ik->check_valid_for_instantiation(false, CHECK_NULL); 1660 ik->initialize(CHECK_NULL); 1661 return ik->allocate_instance(THREAD); 1662 } 1663 1664 instanceHandle InstanceKlass::allocate_instance_handle(TRAPS) { 1665 return instanceHandle(THREAD, allocate_instance(THREAD)); 1666 } 1667 1668 void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) { 1669 if (is_interface() || is_abstract()) { 1670 ResourceMark rm(THREAD); 1671 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError() 1672 : vmSymbols::java_lang_InstantiationException(), external_name()); 1673 } 1674 if (this == vmClasses::Class_klass()) { 1675 ResourceMark rm(THREAD); 1676 THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError() 1677 : vmSymbols::java_lang_IllegalAccessException(), external_name()); 1678 } 1679 } 1680 1681 Klass* InstanceKlass::array_klass(int n, TRAPS) { 1682 // Need load-acquire for lock-free read 1683 if (array_klasses_acquire() == nullptr) { 1684 ResourceMark rm(THREAD); 1685 JavaThread *jt = THREAD; 1686 { 1687 // Atomic creation of array_klasses 1688 MutexLocker ma(THREAD, MultiArray_lock); 1689 1690 // Check if update has already taken place 1691 if (array_klasses() == nullptr) { 1692 ObjArrayKlass* k = ObjArrayKlass::allocate_objArray_klass(class_loader_data(), 1, this, 1693 false, false, CHECK_NULL); 1694 // use 'release' to pair with lock-free load 1695 release_set_array_klasses(k); 1696 } 1697 } 1698 } 1699 // array_klasses() will always be set at this point 1700 ArrayKlass* ak = array_klasses(); 1701 return ak->array_klass(n, THREAD); 1702 } 1703 1704 Klass* InstanceKlass::array_klass_or_null(int n) { 1705 // Need load-acquire for lock-free read 1706 ArrayKlass* ak = array_klasses_acquire(); 1707 if (ak == nullptr) { 1708 return nullptr; 1709 } else { 1710 return ak->array_klass_or_null(n); 1711 } 1712 } 1713 1714 Klass* InstanceKlass::array_klass(TRAPS) { 1715 return array_klass(1, THREAD); 1716 } 1717 1718 Klass* InstanceKlass::array_klass_or_null() { 1719 return array_klass_or_null(1); 1720 } 1721 1722 static int call_class_initializer_counter = 0; // for debugging 1723 1724 Method* InstanceKlass::class_initializer() const { 1725 Method* clinit = find_method( 1726 vmSymbols::class_initializer_name(), vmSymbols::void_method_signature()); 1727 if (clinit != nullptr && clinit->is_class_initializer()) { 1728 return clinit; 1729 } 1730 return nullptr; 1731 } 1732 1733 void InstanceKlass::call_class_initializer(TRAPS) { 1734 if (ReplayCompiles && 1735 (ReplaySuppressInitializers == 1 || 1736 (ReplaySuppressInitializers >= 2 && class_loader() != nullptr))) { 1737 // Hide the existence of the initializer for the purpose of replaying the compile 1738 return; 1739 } 1740 1741 #if INCLUDE_CDS 1742 // This is needed to ensure the consistency of the archived heap objects. 1743 if (has_archived_enum_objs()) { 1744 assert(is_shared(), "must be"); 1745 bool initialized = HeapShared::initialize_enum_klass(this, CHECK); 1746 if (initialized) { 1747 return; 1748 } 1749 } 1750 #endif 1751 1752 methodHandle h_method(THREAD, class_initializer()); 1753 assert(!is_initialized(), "we cannot initialize twice"); 1754 LogTarget(Info, class, init) lt; 1755 if (lt.is_enabled()) { 1756 ResourceMark rm(THREAD); 1757 LogStream ls(lt); 1758 ls.print("%d Initializing ", call_class_initializer_counter++); 1759 name()->print_value_on(&ls); 1760 ls.print_cr("%s (" PTR_FORMAT ")", h_method() == nullptr ? "(no method)" : "", p2i(this)); 1761 } 1762 if (h_method() != nullptr) { 1763 JavaCallArguments args; // No arguments 1764 JavaValue result(T_VOID); 1765 JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args) 1766 } 1767 } 1768 1769 1770 void InstanceKlass::mask_for(const methodHandle& method, int bci, 1771 InterpreterOopMap* entry_for) { 1772 // Lazily create the _oop_map_cache at first request 1773 // Lock-free access requires load_acquire. 1774 OopMapCache* oop_map_cache = Atomic::load_acquire(&_oop_map_cache); 1775 if (oop_map_cache == nullptr) { 1776 MutexLocker x(OopMapCacheAlloc_lock, Mutex::_no_safepoint_check_flag); 1777 // Check if _oop_map_cache was allocated while we were waiting for this lock 1778 if ((oop_map_cache = _oop_map_cache) == nullptr) { 1779 oop_map_cache = new OopMapCache(); 1780 // Ensure _oop_map_cache is stable, since it is examined without a lock 1781 Atomic::release_store(&_oop_map_cache, oop_map_cache); 1782 } 1783 } 1784 // _oop_map_cache is constant after init; lookup below does its own locking. 1785 oop_map_cache->lookup(method, bci, entry_for); 1786 } 1787 1788 1789 FieldInfo InstanceKlass::field(int index) const { 1790 for (AllFieldStream fs(this); !fs.done(); fs.next()) { 1791 if (fs.index() == index) { 1792 return fs.to_FieldInfo(); 1793 } 1794 } 1795 fatal("Field not found"); 1796 return FieldInfo(); 1797 } 1798 1799 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const { 1800 for (JavaFieldStream fs(this); !fs.done(); fs.next()) { 1801 Symbol* f_name = fs.name(); 1802 Symbol* f_sig = fs.signature(); 1803 if (f_name == name && f_sig == sig) { 1804 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index()); 1805 return true; 1806 } 1807 } 1808 return false; 1809 } 1810 1811 1812 Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const { 1813 const int n = local_interfaces()->length(); 1814 for (int i = 0; i < n; i++) { 1815 Klass* intf1 = local_interfaces()->at(i); 1816 assert(intf1->is_interface(), "just checking type"); 1817 // search for field in current interface 1818 if (InstanceKlass::cast(intf1)->find_local_field(name, sig, fd)) { 1819 assert(fd->is_static(), "interface field must be static"); 1820 return intf1; 1821 } 1822 // search for field in direct superinterfaces 1823 Klass* intf2 = InstanceKlass::cast(intf1)->find_interface_field(name, sig, fd); 1824 if (intf2 != nullptr) return intf2; 1825 } 1826 // otherwise field lookup fails 1827 return nullptr; 1828 } 1829 1830 1831 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const { 1832 // search order according to newest JVM spec (5.4.3.2, p.167). 1833 // 1) search for field in current klass 1834 if (find_local_field(name, sig, fd)) { 1835 return const_cast<InstanceKlass*>(this); 1836 } 1837 // 2) search for field recursively in direct superinterfaces 1838 { Klass* intf = find_interface_field(name, sig, fd); 1839 if (intf != nullptr) return intf; 1840 } 1841 // 3) apply field lookup recursively if superclass exists 1842 { Klass* supr = super(); 1843 if (supr != nullptr) return InstanceKlass::cast(supr)->find_field(name, sig, fd); 1844 } 1845 // 4) otherwise field lookup fails 1846 return nullptr; 1847 } 1848 1849 1850 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const { 1851 // search order according to newest JVM spec (5.4.3.2, p.167). 1852 // 1) search for field in current klass 1853 if (find_local_field(name, sig, fd)) { 1854 if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this); 1855 } 1856 // 2) search for field recursively in direct superinterfaces 1857 if (is_static) { 1858 Klass* intf = find_interface_field(name, sig, fd); 1859 if (intf != nullptr) return intf; 1860 } 1861 // 3) apply field lookup recursively if superclass exists 1862 { Klass* supr = super(); 1863 if (supr != nullptr) return InstanceKlass::cast(supr)->find_field(name, sig, is_static, fd); 1864 } 1865 // 4) otherwise field lookup fails 1866 return nullptr; 1867 } 1868 1869 bool InstanceKlass::contains_field_offset(int offset) { 1870 if (this->is_inline_klass()) { 1871 InlineKlass* vk = InlineKlass::cast(this); 1872 return offset >= vk->first_field_offset() && offset < (vk->first_field_offset() + vk->get_exact_size_in_bytes()); 1873 } else { 1874 fieldDescriptor fd; 1875 return find_field_from_offset(offset, false, &fd); 1876 } 1877 } 1878 1879 bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const { 1880 for (JavaFieldStream fs(this); !fs.done(); fs.next()) { 1881 if (fs.offset() == offset) { 1882 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index()); 1883 if (fd->is_static() == is_static) return true; 1884 } 1885 } 1886 return false; 1887 } 1888 1889 1890 bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const { 1891 Klass* klass = const_cast<InstanceKlass*>(this); 1892 while (klass != nullptr) { 1893 if (InstanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) { 1894 return true; 1895 } 1896 klass = klass->super(); 1897 } 1898 return false; 1899 } 1900 1901 1902 void InstanceKlass::methods_do(void f(Method* method)) { 1903 // Methods aren't stable until they are loaded. This can be read outside 1904 // a lock through the ClassLoaderData for profiling 1905 // Redefined scratch classes are on the list and need to be cleaned 1906 if (!is_loaded() && !is_scratch_class()) { 1907 return; 1908 } 1909 1910 int len = methods()->length(); 1911 for (int index = 0; index < len; index++) { 1912 Method* m = methods()->at(index); 1913 assert(m->is_method(), "must be method"); 1914 f(m); 1915 } 1916 } 1917 1918 1919 void InstanceKlass::do_local_static_fields(FieldClosure* cl) { 1920 for (JavaFieldStream fs(this); !fs.done(); fs.next()) { 1921 if (fs.access_flags().is_static()) { 1922 fieldDescriptor& fd = fs.field_descriptor(); 1923 cl->do_field(&fd); 1924 } 1925 } 1926 } 1927 1928 1929 void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle mirror, TRAPS) { 1930 for (JavaFieldStream fs(this); !fs.done(); fs.next()) { 1931 if (fs.access_flags().is_static()) { 1932 fieldDescriptor& fd = fs.field_descriptor(); 1933 f(&fd, mirror, CHECK); 1934 } 1935 } 1936 } 1937 1938 void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) { 1939 InstanceKlass* super = superklass(); 1940 if (super != nullptr) { 1941 super->do_nonstatic_fields(cl); 1942 } 1943 fieldDescriptor fd; 1944 int length = java_fields_count(); 1945 for (int i = 0; i < length; i += 1) { 1946 fd.reinitialize(this, i); 1947 if (!fd.is_static()) { 1948 cl->do_field(&fd); 1949 } 1950 } 1951 } 1952 1953 // first in Pair is offset, second is index. 1954 static int compare_fields_by_offset(Pair<int,int>* a, Pair<int,int>* b) { 1955 return a->first - b->first; 1956 } 1957 1958 void InstanceKlass::print_nonstatic_fields(FieldClosure* cl) { 1959 InstanceKlass* super = superklass(); 1960 if (super != nullptr) { 1961 super->print_nonstatic_fields(cl); 1962 } 1963 ResourceMark rm; 1964 fieldDescriptor fd; 1965 // In DebugInfo nonstatic fields are sorted by offset. 1966 GrowableArray<Pair<int,int> > fields_sorted; 1967 int i = 0; 1968 for (AllFieldStream fs(this); !fs.done(); fs.next()) { 1969 if (!fs.access_flags().is_static()) { 1970 fd = fs.field_descriptor(); 1971 Pair<int,int> f(fs.offset(), fs.index()); 1972 fields_sorted.push(f); 1973 i++; 1974 } 1975 } 1976 if (i > 0) { 1977 int length = i; 1978 assert(length == fields_sorted.length(), "duh"); 1979 // _sort_Fn is defined in growableArray.hpp. 1980 fields_sorted.sort(compare_fields_by_offset); 1981 for (int i = 0; i < length; i++) { 1982 fd.reinitialize(this, fields_sorted.at(i).second); 1983 assert(!fd.is_static() && fd.offset() == fields_sorted.at(i).first, "only nonstatic fields"); 1984 cl->do_field(&fd); 1985 } 1986 } 1987 } 1988 1989 #ifdef ASSERT 1990 static int linear_search(const Array<Method*>* methods, 1991 const Symbol* name, 1992 const Symbol* signature) { 1993 const int len = methods->length(); 1994 for (int index = 0; index < len; index++) { 1995 const Method* const m = methods->at(index); 1996 assert(m->is_method(), "must be method"); 1997 if (m->signature() == signature && m->name() == name) { 1998 return index; 1999 } 2000 } 2001 return -1; 2002 } 2003 #endif 2004 2005 bool InstanceKlass::_disable_method_binary_search = false; 2006 2007 NOINLINE int linear_search(const Array<Method*>* methods, const Symbol* name) { 2008 int len = methods->length(); 2009 int l = 0; 2010 int h = len - 1; 2011 while (l <= h) { 2012 Method* m = methods->at(l); 2013 if (m->name() == name) { 2014 return l; 2015 } 2016 l++; 2017 } 2018 return -1; 2019 } 2020 2021 inline int InstanceKlass::quick_search(const Array<Method*>* methods, const Symbol* name) { 2022 if (_disable_method_binary_search) { 2023 assert(DynamicDumpSharedSpaces, "must be"); 2024 // At the final stage of dynamic dumping, the methods array may not be sorted 2025 // by ascending addresses of their names, so we can't use binary search anymore. 2026 // However, methods with the same name are still laid out consecutively inside the 2027 // methods array, so let's look for the first one that matches. 2028 return linear_search(methods, name); 2029 } 2030 2031 int len = methods->length(); 2032 int l = 0; 2033 int h = len - 1; 2034 2035 // methods are sorted by ascending addresses of their names, so do binary search 2036 while (l <= h) { 2037 int mid = (l + h) >> 1; 2038 Method* m = methods->at(mid); 2039 assert(m->is_method(), "must be method"); 2040 int res = m->name()->fast_compare(name); 2041 if (res == 0) { 2042 return mid; 2043 } else if (res < 0) { 2044 l = mid + 1; 2045 } else { 2046 h = mid - 1; 2047 } 2048 } 2049 return -1; 2050 } 2051 2052 // find_method looks up the name/signature in the local methods array 2053 Method* InstanceKlass::find_method(const Symbol* name, 2054 const Symbol* signature) const { 2055 return find_method_impl(name, signature, 2056 OverpassLookupMode::find, 2057 StaticLookupMode::find, 2058 PrivateLookupMode::find); 2059 } 2060 2061 Method* InstanceKlass::find_method_impl(const Symbol* name, 2062 const Symbol* signature, 2063 OverpassLookupMode overpass_mode, 2064 StaticLookupMode static_mode, 2065 PrivateLookupMode private_mode) const { 2066 return InstanceKlass::find_method_impl(methods(), 2067 name, 2068 signature, 2069 overpass_mode, 2070 static_mode, 2071 private_mode); 2072 } 2073 2074 // find_instance_method looks up the name/signature in the local methods array 2075 // and skips over static methods 2076 Method* InstanceKlass::find_instance_method(const Array<Method*>* methods, 2077 const Symbol* name, 2078 const Symbol* signature, 2079 PrivateLookupMode private_mode) { 2080 Method* const meth = InstanceKlass::find_method_impl(methods, 2081 name, 2082 signature, 2083 OverpassLookupMode::find, 2084 StaticLookupMode::skip, 2085 private_mode); 2086 assert(((meth == nullptr) || !meth->is_static()), 2087 "find_instance_method should have skipped statics"); 2088 return meth; 2089 } 2090 2091 // find_instance_method looks up the name/signature in the local methods array 2092 // and skips over static methods 2093 Method* InstanceKlass::find_instance_method(const Symbol* name, 2094 const Symbol* signature, 2095 PrivateLookupMode private_mode) const { 2096 return InstanceKlass::find_instance_method(methods(), name, signature, private_mode); 2097 } 2098 2099 // Find looks up the name/signature in the local methods array 2100 // and filters on the overpass, static and private flags 2101 // This returns the first one found 2102 // note that the local methods array can have up to one overpass, one static 2103 // and one instance (private or not) with the same name/signature 2104 Method* InstanceKlass::find_local_method(const Symbol* name, 2105 const Symbol* signature, 2106 OverpassLookupMode overpass_mode, 2107 StaticLookupMode static_mode, 2108 PrivateLookupMode private_mode) const { 2109 return InstanceKlass::find_method_impl(methods(), 2110 name, 2111 signature, 2112 overpass_mode, 2113 static_mode, 2114 private_mode); 2115 } 2116 2117 // Find looks up the name/signature in the local methods array 2118 // and filters on the overpass, static and private flags 2119 // This returns the first one found 2120 // note that the local methods array can have up to one overpass, one static 2121 // and one instance (private or not) with the same name/signature 2122 Method* InstanceKlass::find_local_method(const Array<Method*>* methods, 2123 const Symbol* name, 2124 const Symbol* signature, 2125 OverpassLookupMode overpass_mode, 2126 StaticLookupMode static_mode, 2127 PrivateLookupMode private_mode) { 2128 return InstanceKlass::find_method_impl(methods, 2129 name, 2130 signature, 2131 overpass_mode, 2132 static_mode, 2133 private_mode); 2134 } 2135 2136 Method* InstanceKlass::find_method(const Array<Method*>* methods, 2137 const Symbol* name, 2138 const Symbol* signature) { 2139 return InstanceKlass::find_method_impl(methods, 2140 name, 2141 signature, 2142 OverpassLookupMode::find, 2143 StaticLookupMode::find, 2144 PrivateLookupMode::find); 2145 } 2146 2147 Method* InstanceKlass::find_method_impl(const Array<Method*>* methods, 2148 const Symbol* name, 2149 const Symbol* signature, 2150 OverpassLookupMode overpass_mode, 2151 StaticLookupMode static_mode, 2152 PrivateLookupMode private_mode) { 2153 int hit = find_method_index(methods, name, signature, overpass_mode, static_mode, private_mode); 2154 return hit >= 0 ? methods->at(hit): nullptr; 2155 } 2156 2157 // true if method matches signature and conforms to skipping_X conditions. 2158 static bool method_matches(const Method* m, 2159 const Symbol* signature, 2160 bool skipping_overpass, 2161 bool skipping_static, 2162 bool skipping_private) { 2163 return ((m->signature() == signature) && 2164 (!skipping_overpass || !m->is_overpass()) && 2165 (!skipping_static || !m->is_static()) && 2166 (!skipping_private || !m->is_private())); 2167 } 2168 2169 // Used directly for default_methods to find the index into the 2170 // default_vtable_indices, and indirectly by find_method 2171 // find_method_index looks in the local methods array to return the index 2172 // of the matching name/signature. If, overpass methods are being ignored, 2173 // the search continues to find a potential non-overpass match. This capability 2174 // is important during method resolution to prefer a static method, for example, 2175 // over an overpass method. 2176 // There is the possibility in any _method's array to have the same name/signature 2177 // for a static method, an overpass method and a local instance method 2178 // To correctly catch a given method, the search criteria may need 2179 // to explicitly skip the other two. For local instance methods, it 2180 // is often necessary to skip private methods 2181 int InstanceKlass::find_method_index(const Array<Method*>* methods, 2182 const Symbol* name, 2183 const Symbol* signature, 2184 OverpassLookupMode overpass_mode, 2185 StaticLookupMode static_mode, 2186 PrivateLookupMode private_mode) { 2187 const bool skipping_overpass = (overpass_mode == OverpassLookupMode::skip); 2188 const bool skipping_static = (static_mode == StaticLookupMode::skip); 2189 const bool skipping_private = (private_mode == PrivateLookupMode::skip); 2190 const int hit = quick_search(methods, name); 2191 if (hit != -1) { 2192 const Method* const m = methods->at(hit); 2193 2194 // Do linear search to find matching signature. First, quick check 2195 // for common case, ignoring overpasses if requested. 2196 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) { 2197 return hit; 2198 } 2199 2200 // search downwards through overloaded methods 2201 int i; 2202 for (i = hit - 1; i >= 0; --i) { 2203 const Method* const m = methods->at(i); 2204 assert(m->is_method(), "must be method"); 2205 if (m->name() != name) { 2206 break; 2207 } 2208 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) { 2209 return i; 2210 } 2211 } 2212 // search upwards 2213 for (i = hit + 1; i < methods->length(); ++i) { 2214 const Method* const m = methods->at(i); 2215 assert(m->is_method(), "must be method"); 2216 if (m->name() != name) { 2217 break; 2218 } 2219 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) { 2220 return i; 2221 } 2222 } 2223 // not found 2224 #ifdef ASSERT 2225 const int index = (skipping_overpass || skipping_static || skipping_private) ? -1 : 2226 linear_search(methods, name, signature); 2227 assert(-1 == index, "binary search should have found entry %d", index); 2228 #endif 2229 } 2230 return -1; 2231 } 2232 2233 int InstanceKlass::find_method_by_name(const Symbol* name, int* end) const { 2234 return find_method_by_name(methods(), name, end); 2235 } 2236 2237 int InstanceKlass::find_method_by_name(const Array<Method*>* methods, 2238 const Symbol* name, 2239 int* end_ptr) { 2240 assert(end_ptr != nullptr, "just checking"); 2241 int start = quick_search(methods, name); 2242 int end = start + 1; 2243 if (start != -1) { 2244 while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start; 2245 while (end < methods->length() && (methods->at(end))->name() == name) ++end; 2246 *end_ptr = end; 2247 return start; 2248 } 2249 return -1; 2250 } 2251 2252 // uncached_lookup_method searches both the local class methods array and all 2253 // superclasses methods arrays, skipping any overpass methods in superclasses, 2254 // and possibly skipping private methods. 2255 Method* InstanceKlass::uncached_lookup_method(const Symbol* name, 2256 const Symbol* signature, 2257 OverpassLookupMode overpass_mode, 2258 PrivateLookupMode private_mode) const { 2259 OverpassLookupMode overpass_local_mode = overpass_mode; 2260 const Klass* klass = this; 2261 while (klass != nullptr) { 2262 Method* const method = InstanceKlass::cast(klass)->find_method_impl(name, 2263 signature, 2264 overpass_local_mode, 2265 StaticLookupMode::find, 2266 private_mode); 2267 if (method != nullptr) { 2268 return method; 2269 } 2270 if (name == vmSymbols::object_initializer_name() || 2271 name == vmSymbols::inline_factory_name()) { 2272 break; // <init> and <vnew> is never inherited 2273 } 2274 klass = klass->super(); 2275 overpass_local_mode = OverpassLookupMode::skip; // Always ignore overpass methods in superclasses 2276 } 2277 return nullptr; 2278 } 2279 2280 #ifdef ASSERT 2281 // search through class hierarchy and return true if this class or 2282 // one of the superclasses was redefined 2283 bool InstanceKlass::has_redefined_this_or_super() const { 2284 const Klass* klass = this; 2285 while (klass != nullptr) { 2286 if (InstanceKlass::cast(klass)->has_been_redefined()) { 2287 return true; 2288 } 2289 klass = klass->super(); 2290 } 2291 return false; 2292 } 2293 #endif 2294 2295 // lookup a method in the default methods list then in all transitive interfaces 2296 // Do NOT return private or static methods 2297 Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name, 2298 Symbol* signature) const { 2299 Method* m = nullptr; 2300 if (default_methods() != nullptr) { 2301 m = find_method(default_methods(), name, signature); 2302 } 2303 // Look up interfaces 2304 if (m == nullptr) { 2305 m = lookup_method_in_all_interfaces(name, signature, DefaultsLookupMode::find); 2306 } 2307 return m; 2308 } 2309 2310 // lookup a method in all the interfaces that this class implements 2311 // Do NOT return private or static methods, new in JDK8 which are not externally visible 2312 // They should only be found in the initial InterfaceMethodRef 2313 Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name, 2314 Symbol* signature, 2315 DefaultsLookupMode defaults_mode) const { 2316 Array<InstanceKlass*>* all_ifs = transitive_interfaces(); 2317 int num_ifs = all_ifs->length(); 2318 InstanceKlass *ik = nullptr; 2319 for (int i = 0; i < num_ifs; i++) { 2320 ik = all_ifs->at(i); 2321 Method* m = ik->lookup_method(name, signature); 2322 if (m != nullptr && m->is_public() && !m->is_static() && 2323 ((defaults_mode != DefaultsLookupMode::skip) || !m->is_default_method())) { 2324 return m; 2325 } 2326 } 2327 return nullptr; 2328 } 2329 2330 PrintClassClosure::PrintClassClosure(outputStream* st, bool verbose) 2331 :_st(st), _verbose(verbose) { 2332 ResourceMark rm; 2333 _st->print("%-18s ", "KlassAddr"); 2334 _st->print("%-4s ", "Size"); 2335 _st->print("%-20s ", "State"); 2336 _st->print("%-7s ", "Flags"); 2337 _st->print("%-5s ", "ClassName"); 2338 _st->cr(); 2339 } 2340 2341 void PrintClassClosure::do_klass(Klass* k) { 2342 ResourceMark rm; 2343 // klass pointer 2344 _st->print(PTR_FORMAT " ", p2i(k)); 2345 // klass size 2346 _st->print("%4d ", k->size()); 2347 // initialization state 2348 if (k->is_instance_klass()) { 2349 _st->print("%-20s ",InstanceKlass::cast(k)->init_state_name()); 2350 } else { 2351 _st->print("%-20s ",""); 2352 } 2353 // misc flags(Changes should synced with ClassesDCmd::ClassesDCmd help doc) 2354 char buf[10]; 2355 int i = 0; 2356 if (k->has_finalizer()) buf[i++] = 'F'; 2357 if (k->is_instance_klass()) { 2358 InstanceKlass* ik = InstanceKlass::cast(k); 2359 if (ik->has_final_method()) buf[i++] = 'f'; 2360 if (ik->is_rewritten()) buf[i++] = 'W'; 2361 if (ik->is_contended()) buf[i++] = 'C'; 2362 if (ik->has_been_redefined()) buf[i++] = 'R'; 2363 if (ik->is_shared()) buf[i++] = 'S'; 2364 } 2365 buf[i++] = '\0'; 2366 _st->print("%-7s ", buf); 2367 // klass name 2368 _st->print("%-5s ", k->external_name()); 2369 // end 2370 _st->cr(); 2371 if (_verbose) { 2372 k->print_on(_st); 2373 } 2374 } 2375 2376 /* jni_id_for for jfieldIds only */ 2377 JNIid* InstanceKlass::jni_id_for(int offset) { 2378 MutexLocker ml(JfieldIdCreation_lock); 2379 JNIid* probe = jni_ids() == nullptr ? nullptr : jni_ids()->find(offset); 2380 if (probe == nullptr) { 2381 // Allocate new static field identifier 2382 probe = new JNIid(this, offset, jni_ids()); 2383 set_jni_ids(probe); 2384 } 2385 return probe; 2386 } 2387 2388 u2 InstanceKlass::enclosing_method_data(int offset) const { 2389 const Array<jushort>* const inner_class_list = inner_classes(); 2390 if (inner_class_list == nullptr) { 2391 return 0; 2392 } 2393 const int length = inner_class_list->length(); 2394 if (length % inner_class_next_offset == 0) { 2395 return 0; 2396 } 2397 const int index = length - enclosing_method_attribute_size; 2398 assert(offset < enclosing_method_attribute_size, "invalid offset"); 2399 return inner_class_list->at(index + offset); 2400 } 2401 2402 void InstanceKlass::set_enclosing_method_indices(u2 class_index, 2403 u2 method_index) { 2404 Array<jushort>* inner_class_list = inner_classes(); 2405 assert (inner_class_list != nullptr, "_inner_classes list is not set up"); 2406 int length = inner_class_list->length(); 2407 if (length % inner_class_next_offset == enclosing_method_attribute_size) { 2408 int index = length - enclosing_method_attribute_size; 2409 inner_class_list->at_put( 2410 index + enclosing_method_class_index_offset, class_index); 2411 inner_class_list->at_put( 2412 index + enclosing_method_method_index_offset, method_index); 2413 } 2414 } 2415 2416 // Lookup or create a jmethodID. 2417 // This code is called by the VMThread and JavaThreads so the 2418 // locking has to be done very carefully to avoid deadlocks 2419 // and/or other cache consistency problems. 2420 // 2421 jmethodID InstanceKlass::get_jmethod_id(const methodHandle& method_h) { 2422 size_t idnum = (size_t)method_h->method_idnum(); 2423 jmethodID* jmeths = methods_jmethod_ids_acquire(); 2424 size_t length = 0; 2425 jmethodID id = nullptr; 2426 2427 // We use a double-check locking idiom here because this cache is 2428 // performance sensitive. In the normal system, this cache only 2429 // transitions from null to non-null which is safe because we use 2430 // release_set_methods_jmethod_ids() to advertise the new cache. 2431 // A partially constructed cache should never be seen by a racing 2432 // thread. We also use release_store() to save a new jmethodID 2433 // in the cache so a partially constructed jmethodID should never be 2434 // seen either. Cache reads of existing jmethodIDs proceed without a 2435 // lock, but cache writes of a new jmethodID requires uniqueness and 2436 // creation of the cache itself requires no leaks so a lock is 2437 // generally acquired in those two cases. 2438 // 2439 // If the RedefineClasses() API has been used, then this cache can 2440 // grow and we'll have transitions from non-null to bigger non-null. 2441 // Cache creation requires no leaks and we require safety between all 2442 // cache accesses and freeing of the old cache so a lock is generally 2443 // acquired when the RedefineClasses() API has been used. 2444 2445 if (jmeths != nullptr) { 2446 // the cache already exists 2447 if (!idnum_can_increment()) { 2448 // the cache can't grow so we can just get the current values 2449 get_jmethod_id_length_value(jmeths, idnum, &length, &id); 2450 } else { 2451 MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag); 2452 get_jmethod_id_length_value(jmeths, idnum, &length, &id); 2453 } 2454 } 2455 // implied else: 2456 // we need to allocate a cache so default length and id values are good 2457 2458 if (jmeths == nullptr || // no cache yet 2459 length <= idnum || // cache is too short 2460 id == nullptr) { // cache doesn't contain entry 2461 2462 // This function can be called by the VMThread or GC worker threads so we 2463 // have to do all things that might block on a safepoint before grabbing the lock. 2464 // Otherwise, we can deadlock with the VMThread or have a cache 2465 // consistency issue. These vars keep track of what we might have 2466 // to free after the lock is dropped. 2467 jmethodID to_dealloc_id = nullptr; 2468 jmethodID* to_dealloc_jmeths = nullptr; 2469 2470 // may not allocate new_jmeths or use it if we allocate it 2471 jmethodID* new_jmeths = nullptr; 2472 if (length <= idnum) { 2473 // allocate a new cache that might be used 2474 size_t size = MAX2(idnum+1, (size_t)idnum_allocated_count()); 2475 new_jmeths = NEW_C_HEAP_ARRAY(jmethodID, size+1, mtClass); 2476 memset(new_jmeths, 0, (size+1)*sizeof(jmethodID)); 2477 // cache size is stored in element[0], other elements offset by one 2478 new_jmeths[0] = (jmethodID)size; 2479 } 2480 2481 // allocate a new jmethodID that might be used 2482 { 2483 MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag); 2484 jmethodID new_id = nullptr; 2485 if (method_h->is_old() && !method_h->is_obsolete()) { 2486 // The method passed in is old (but not obsolete), we need to use the current version 2487 Method* current_method = method_with_idnum((int)idnum); 2488 assert(current_method != nullptr, "old and but not obsolete, so should exist"); 2489 new_id = Method::make_jmethod_id(class_loader_data(), current_method); 2490 } else { 2491 // It is the current version of the method or an obsolete method, 2492 // use the version passed in 2493 new_id = Method::make_jmethod_id(class_loader_data(), method_h()); 2494 } 2495 2496 id = get_jmethod_id_fetch_or_update(idnum, new_id, new_jmeths, 2497 &to_dealloc_id, &to_dealloc_jmeths); 2498 } 2499 2500 // The lock has been dropped so we can free resources. 2501 // Free up either the old cache or the new cache if we allocated one. 2502 if (to_dealloc_jmeths != nullptr) { 2503 FreeHeap(to_dealloc_jmeths); 2504 } 2505 // free up the new ID since it wasn't needed 2506 if (to_dealloc_id != nullptr) { 2507 Method::destroy_jmethod_id(class_loader_data(), to_dealloc_id); 2508 } 2509 } 2510 return id; 2511 } 2512 2513 // Figure out how many jmethodIDs haven't been allocated, and make 2514 // sure space for them is pre-allocated. This makes getting all 2515 // method ids much, much faster with classes with more than 8 2516 // methods, and has a *substantial* effect on performance with jvmti 2517 // code that loads all jmethodIDs for all classes. 2518 void InstanceKlass::ensure_space_for_methodids(int start_offset) { 2519 int new_jmeths = 0; 2520 int length = methods()->length(); 2521 for (int index = start_offset; index < length; index++) { 2522 Method* m = methods()->at(index); 2523 jmethodID id = m->find_jmethod_id_or_null(); 2524 if (id == nullptr) { 2525 new_jmeths++; 2526 } 2527 } 2528 if (new_jmeths != 0) { 2529 Method::ensure_jmethod_ids(class_loader_data(), new_jmeths); 2530 } 2531 } 2532 2533 // Common code to fetch the jmethodID from the cache or update the 2534 // cache with the new jmethodID. This function should never do anything 2535 // that causes the caller to go to a safepoint or we can deadlock with 2536 // the VMThread or have cache consistency issues. 2537 // 2538 jmethodID InstanceKlass::get_jmethod_id_fetch_or_update( 2539 size_t idnum, jmethodID new_id, 2540 jmethodID* new_jmeths, jmethodID* to_dealloc_id_p, 2541 jmethodID** to_dealloc_jmeths_p) { 2542 assert(new_id != nullptr, "sanity check"); 2543 assert(to_dealloc_id_p != nullptr, "sanity check"); 2544 assert(to_dealloc_jmeths_p != nullptr, "sanity check"); 2545 assert(JmethodIdCreation_lock->owned_by_self(), "sanity check"); 2546 2547 // reacquire the cache - we are locked, single threaded or at a safepoint 2548 jmethodID* jmeths = methods_jmethod_ids_acquire(); 2549 jmethodID id = nullptr; 2550 size_t length = 0; 2551 2552 if (jmeths == nullptr || // no cache yet 2553 (length = (size_t)jmeths[0]) <= idnum) { // cache is too short 2554 if (jmeths != nullptr) { 2555 // copy any existing entries from the old cache 2556 for (size_t index = 0; index < length; index++) { 2557 new_jmeths[index+1] = jmeths[index+1]; 2558 } 2559 *to_dealloc_jmeths_p = jmeths; // save old cache for later delete 2560 } 2561 release_set_methods_jmethod_ids(jmeths = new_jmeths); 2562 } else { 2563 // fetch jmethodID (if any) from the existing cache 2564 id = jmeths[idnum+1]; 2565 *to_dealloc_jmeths_p = new_jmeths; // save new cache for later delete 2566 } 2567 if (id == nullptr) { 2568 // No matching jmethodID in the existing cache or we have a new 2569 // cache or we just grew the cache. This cache write is done here 2570 // by the first thread to win the foot race because a jmethodID 2571 // needs to be unique once it is generally available. 2572 id = new_id; 2573 2574 // The jmethodID cache can be read while unlocked so we have to 2575 // make sure the new jmethodID is complete before installing it 2576 // in the cache. 2577 Atomic::release_store(&jmeths[idnum+1], id); 2578 } else { 2579 *to_dealloc_id_p = new_id; // save new id for later delete 2580 } 2581 return id; 2582 } 2583 2584 2585 // Common code to get the jmethodID cache length and the jmethodID 2586 // value at index idnum if there is one. 2587 // 2588 void InstanceKlass::get_jmethod_id_length_value(jmethodID* cache, 2589 size_t idnum, size_t *length_p, jmethodID* id_p) { 2590 assert(cache != nullptr, "sanity check"); 2591 assert(length_p != nullptr, "sanity check"); 2592 assert(id_p != nullptr, "sanity check"); 2593 2594 // cache size is stored in element[0], other elements offset by one 2595 *length_p = (size_t)cache[0]; 2596 if (*length_p <= idnum) { // cache is too short 2597 *id_p = nullptr; 2598 } else { 2599 *id_p = cache[idnum+1]; // fetch jmethodID (if any) 2600 } 2601 } 2602 2603 2604 // Lookup a jmethodID, null if not found. Do no blocking, no allocations, no handles 2605 jmethodID InstanceKlass::jmethod_id_or_null(Method* method) { 2606 size_t idnum = (size_t)method->method_idnum(); 2607 jmethodID* jmeths = methods_jmethod_ids_acquire(); 2608 size_t length; // length assigned as debugging crumb 2609 jmethodID id = nullptr; 2610 if (jmeths != nullptr && // If there is a cache 2611 (length = (size_t)jmeths[0]) > idnum) { // and if it is long enough, 2612 id = jmeths[idnum+1]; // Look up the id (may be null) 2613 } 2614 return id; 2615 } 2616 2617 inline DependencyContext InstanceKlass::dependencies() { 2618 DependencyContext dep_context(&_dep_context, &_dep_context_last_cleaned); 2619 return dep_context; 2620 } 2621 2622 void InstanceKlass::mark_dependent_nmethods(DeoptimizationScope* deopt_scope, KlassDepChange& changes) { 2623 dependencies().mark_dependent_nmethods(deopt_scope, changes); 2624 } 2625 2626 void InstanceKlass::add_dependent_nmethod(nmethod* nm) { 2627 dependencies().add_dependent_nmethod(nm); 2628 } 2629 2630 void InstanceKlass::clean_dependency_context() { 2631 dependencies().clean_unloading_dependents(); 2632 } 2633 2634 #ifndef PRODUCT 2635 void InstanceKlass::print_dependent_nmethods(bool verbose) { 2636 dependencies().print_dependent_nmethods(verbose); 2637 } 2638 2639 bool InstanceKlass::is_dependent_nmethod(nmethod* nm) { 2640 return dependencies().is_dependent_nmethod(nm); 2641 } 2642 #endif //PRODUCT 2643 2644 void InstanceKlass::clean_weak_instanceklass_links() { 2645 clean_implementors_list(); 2646 clean_method_data(); 2647 } 2648 2649 void InstanceKlass::clean_implementors_list() { 2650 assert(is_loader_alive(), "this klass should be live"); 2651 if (is_interface()) { 2652 assert (ClassUnloading, "only called for ClassUnloading"); 2653 for (;;) { 2654 // Use load_acquire due to competing with inserts 2655 InstanceKlass* impl = Atomic::load_acquire(adr_implementor()); 2656 if (impl != nullptr && !impl->is_loader_alive()) { 2657 // null this field, might be an unloaded instance klass or null 2658 InstanceKlass* volatile* iklass = adr_implementor(); 2659 if (Atomic::cmpxchg(iklass, impl, (InstanceKlass*)nullptr) == impl) { 2660 // Successfully unlinking implementor. 2661 if (log_is_enabled(Trace, class, unload)) { 2662 ResourceMark rm; 2663 log_trace(class, unload)("unlinking class (implementor): %s", impl->external_name()); 2664 } 2665 return; 2666 } 2667 } else { 2668 return; 2669 } 2670 } 2671 } 2672 } 2673 2674 void InstanceKlass::clean_method_data() { 2675 for (int m = 0; m < methods()->length(); m++) { 2676 MethodData* mdo = methods()->at(m)->method_data(); 2677 if (mdo != nullptr) { 2678 MutexLocker ml(SafepointSynchronize::is_at_safepoint() ? nullptr : mdo->extra_data_lock()); 2679 mdo->clean_method_data(/*always_clean*/false); 2680 } 2681 } 2682 } 2683 2684 void InstanceKlass::metaspace_pointers_do(MetaspaceClosure* it) { 2685 Klass::metaspace_pointers_do(it); 2686 2687 if (log_is_enabled(Trace, cds)) { 2688 ResourceMark rm; 2689 log_trace(cds)("Iter(InstanceKlass): %p (%s)", this, external_name()); 2690 } 2691 2692 it->push(&_annotations); 2693 it->push((Klass**)&_array_klasses); 2694 if (!is_rewritten()) { 2695 it->push(&_constants, MetaspaceClosure::_writable); 2696 } else { 2697 it->push(&_constants); 2698 } 2699 it->push(&_inner_classes); 2700 #if INCLUDE_JVMTI 2701 it->push(&_previous_versions); 2702 #endif 2703 #if INCLUDE_CDS 2704 // For "old" classes with methods containing the jsr bytecode, the _methods array will 2705 // be rewritten during runtime (see Rewriter::rewrite_jsrs()). So setting the _methods to 2706 // be writable. The length check on the _methods is necessary because classes which 2707 // don't have any methods share the Universe::_the_empty_method_array which is in the RO region. 2708 if (_methods != nullptr && _methods->length() > 0 && 2709 !can_be_verified_at_dumptime() && methods_contain_jsr_bytecode()) { 2710 // To handle jsr bytecode, new Method* maybe stored into _methods 2711 it->push(&_methods, MetaspaceClosure::_writable); 2712 } else { 2713 #endif 2714 it->push(&_methods); 2715 #if INCLUDE_CDS 2716 } 2717 #endif 2718 it->push(&_default_methods); 2719 it->push(&_local_interfaces); 2720 it->push(&_transitive_interfaces); 2721 it->push(&_method_ordering); 2722 if (!is_rewritten()) { 2723 it->push(&_default_vtable_indices, MetaspaceClosure::_writable); 2724 } else { 2725 it->push(&_default_vtable_indices); 2726 } 2727 2728 it->push(&_fieldinfo_stream); 2729 // _fields_status might be written into by Rewriter::scan_method() -> fd.set_has_initialized_final_update() 2730 it->push(&_fields_status, MetaspaceClosure::_writable); 2731 2732 if (itable_length() > 0) { 2733 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable(); 2734 int method_table_offset_in_words = ioe->offset()/wordSize; 2735 int itable_offset_in_words = (int)(start_of_itable() - (intptr_t*)this); 2736 2737 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words) 2738 / itableOffsetEntry::size(); 2739 2740 for (int i = 0; i < nof_interfaces; i ++, ioe ++) { 2741 if (ioe->interface_klass() != nullptr) { 2742 it->push(ioe->interface_klass_addr()); 2743 itableMethodEntry* ime = ioe->first_method_entry(this); 2744 int n = klassItable::method_count_for_interface(ioe->interface_klass()); 2745 for (int index = 0; index < n; index ++) { 2746 it->push(ime[index].method_addr()); 2747 } 2748 } 2749 } 2750 } 2751 2752 it->push(&_nest_members); 2753 it->push(&_permitted_subclasses); 2754 it->push(&_preload_classes); 2755 it->push(&_record_components); 2756 2757 if (has_inline_type_fields()) { 2758 for (int i = 0; i < java_fields_count(); i++) { 2759 it->push(&((Klass**)adr_inline_type_field_klasses())[i]); 2760 } 2761 } 2762 } 2763 2764 #if INCLUDE_CDS 2765 void InstanceKlass::remove_unshareable_info() { 2766 2767 if (is_linked()) { 2768 assert(can_be_verified_at_dumptime(), "must be"); 2769 // Remember this so we can avoid walking the hierarchy at runtime. 2770 set_verified_at_dump_time(); 2771 } 2772 2773 Klass::remove_unshareable_info(); 2774 2775 if (SystemDictionaryShared::has_class_failed_verification(this)) { 2776 // Classes are attempted to link during dumping and may fail, 2777 // but these classes are still in the dictionary and class list in CLD. 2778 // If the class has failed verification, there is nothing else to remove. 2779 return; 2780 } 2781 2782 // Reset to the 'allocated' state to prevent any premature accessing to 2783 // a shared class at runtime while the class is still being loaded and 2784 // restored. A class' init_state is set to 'loaded' at runtime when it's 2785 // being added to class hierarchy (see InstanceKlass:::add_to_hierarchy()). 2786 _init_state = allocated; 2787 2788 { // Otherwise this needs to take out the Compile_lock. 2789 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint"); 2790 init_implementor(); 2791 } 2792 2793 constants()->remove_unshareable_info(); 2794 2795 for (int i = 0; i < methods()->length(); i++) { 2796 Method* m = methods()->at(i); 2797 m->remove_unshareable_info(); 2798 } 2799 2800 // do array classes also. 2801 if (array_klasses() != nullptr) { 2802 array_klasses()->remove_unshareable_info(); 2803 } 2804 2805 if (has_inline_type_fields()) { 2806 for (AllFieldStream fs(this); !fs.done(); fs.next()) { 2807 if (fs.is_null_free_inline_type()) { 2808 reset_inline_type_field_klass(fs.index()); 2809 } 2810 } 2811 } 2812 2813 // These are not allocated from metaspace. They are safe to set to nullptr. 2814 _source_debug_extension = nullptr; 2815 _dep_context = nullptr; 2816 _osr_nmethods_head = nullptr; 2817 #if INCLUDE_JVMTI 2818 _breakpoints = nullptr; 2819 _previous_versions = nullptr; 2820 _cached_class_file = nullptr; 2821 _jvmti_cached_class_field_map = nullptr; 2822 #endif 2823 2824 _init_thread = nullptr; 2825 _methods_jmethod_ids = nullptr; 2826 _jni_ids = nullptr; 2827 _oop_map_cache = nullptr; 2828 // clear _nest_host to ensure re-load at runtime 2829 _nest_host = nullptr; 2830 init_shared_package_entry(); 2831 _dep_context_last_cleaned = 0; 2832 _init_monitor = nullptr; 2833 2834 remove_unshareable_flags(); 2835 } 2836 2837 void InstanceKlass::remove_unshareable_flags() { 2838 // clear all the flags/stats that shouldn't be in the archived version 2839 assert(!is_scratch_class(), "must be"); 2840 assert(!has_been_redefined(), "must be"); 2841 #if INCLUDE_JVMTI 2842 set_is_being_redefined(false); 2843 #endif 2844 set_has_resolved_methods(false); 2845 } 2846 2847 void InstanceKlass::remove_java_mirror() { 2848 Klass::remove_java_mirror(); 2849 2850 // do array classes also. 2851 if (array_klasses() != nullptr) { 2852 array_klasses()->remove_java_mirror(); 2853 } 2854 } 2855 2856 void InstanceKlass::init_shared_package_entry() { 2857 #if !INCLUDE_CDS_JAVA_HEAP 2858 _package_entry = nullptr; 2859 #else 2860 if (!MetaspaceShared::use_full_module_graph()) { 2861 _package_entry = nullptr; 2862 } else if (DynamicDumpSharedSpaces) { 2863 if (!MetaspaceShared::is_in_shared_metaspace(_package_entry)) { 2864 _package_entry = nullptr; 2865 } 2866 } else { 2867 if (is_shared_unregistered_class()) { 2868 _package_entry = nullptr; 2869 } else { 2870 _package_entry = PackageEntry::get_archived_entry(_package_entry); 2871 } 2872 } 2873 ArchivePtrMarker::mark_pointer((address**)&_package_entry); 2874 #endif 2875 } 2876 2877 void InstanceKlass::compute_has_loops_flag_for_methods() { 2878 Array<Method*>* methods = this->methods(); 2879 for (int index = 0; index < methods->length(); ++index) { 2880 Method* m = methods->at(index); 2881 if (!m->is_overpass()) { // work around JDK-8305771 2882 m->compute_has_loops_flag(); 2883 } 2884 } 2885 } 2886 2887 void InstanceKlass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain, 2888 PackageEntry* pkg_entry, TRAPS) { 2889 // InstanceKlass::add_to_hierarchy() sets the init_state to loaded 2890 // before the InstanceKlass is added to the SystemDictionary. Make 2891 // sure the current state is <loaded. 2892 assert(!is_loaded(), "invalid init state"); 2893 assert(!shared_loading_failed(), "Must not try to load failed class again"); 2894 set_package(loader_data, pkg_entry, CHECK); 2895 Klass::restore_unshareable_info(loader_data, protection_domain, CHECK); 2896 2897 if (is_inline_klass()) { 2898 InlineKlass::cast(this)->initialize_calling_convention(CHECK); 2899 } 2900 2901 Array<Method*>* methods = this->methods(); 2902 int num_methods = methods->length(); 2903 for (int index = 0; index < num_methods; ++index) { 2904 methods->at(index)->restore_unshareable_info(CHECK); 2905 } 2906 #if INCLUDE_JVMTI 2907 if (JvmtiExport::has_redefined_a_class()) { 2908 // Reinitialize vtable because RedefineClasses may have changed some 2909 // entries in this vtable for super classes so the CDS vtable might 2910 // point to old or obsolete entries. RedefineClasses doesn't fix up 2911 // vtables in the shared system dictionary, only the main one. 2912 // It also redefines the itable too so fix that too. 2913 // First fix any default methods that point to a super class that may 2914 // have been redefined. 2915 bool trace_name_printed = false; 2916 adjust_default_methods(&trace_name_printed); 2917 vtable().initialize_vtable(); 2918 itable().initialize_itable(); 2919 } 2920 #endif 2921 2922 // restore constant pool resolved references 2923 constants()->restore_unshareable_info(CHECK); 2924 2925 if (array_klasses() != nullptr) { 2926 // To get a consistent list of classes we need MultiArray_lock to ensure 2927 // array classes aren't observed while they are being restored. 2928 MutexLocker ml(MultiArray_lock); 2929 // Array classes have null protection domain. 2930 // --> see ArrayKlass::complete_create_array_klass() 2931 array_klasses()->restore_unshareable_info(ClassLoaderData::the_null_class_loader_data(), Handle(), CHECK); 2932 } 2933 2934 // Initialize @ValueBased class annotation 2935 if (DiagnoseSyncOnValueBasedClasses && has_value_based_class_annotation()) { 2936 set_is_value_based(); 2937 } 2938 2939 // restore the monitor 2940 _init_monitor = create_init_monitor("InstanceKlassInitMonitorRestored_lock"); 2941 } 2942 2943 // Check if a class or any of its supertypes has a version older than 50. 2944 // CDS will not perform verification of old classes during dump time because 2945 // without changing the old verifier, the verification constraint cannot be 2946 // retrieved during dump time. 2947 // Verification of archived old classes will be performed during run time. 2948 bool InstanceKlass::can_be_verified_at_dumptime() const { 2949 if (MetaspaceShared::is_in_shared_metaspace(this)) { 2950 // This is a class that was dumped into the base archive, so we know 2951 // it was verified at dump time. 2952 return true; 2953 } 2954 if (major_version() < 50 /*JAVA_6_VERSION*/) { 2955 return false; 2956 } 2957 if (java_super() != nullptr && !java_super()->can_be_verified_at_dumptime()) { 2958 return false; 2959 } 2960 Array<InstanceKlass*>* interfaces = local_interfaces(); 2961 int len = interfaces->length(); 2962 for (int i = 0; i < len; i++) { 2963 if (!interfaces->at(i)->can_be_verified_at_dumptime()) { 2964 return false; 2965 } 2966 } 2967 return true; 2968 } 2969 2970 bool InstanceKlass::methods_contain_jsr_bytecode() const { 2971 Thread* thread = Thread::current(); 2972 for (int i = 0; i < _methods->length(); i++) { 2973 methodHandle m(thread, _methods->at(i)); 2974 BytecodeStream bcs(m); 2975 while (!bcs.is_last_bytecode()) { 2976 Bytecodes::Code opcode = bcs.next(); 2977 if (opcode == Bytecodes::_jsr || opcode == Bytecodes::_jsr_w) { 2978 return true; 2979 } 2980 } 2981 } 2982 return false; 2983 } 2984 #endif // INCLUDE_CDS 2985 2986 #if INCLUDE_JVMTI 2987 static void clear_all_breakpoints(Method* m) { 2988 m->clear_all_breakpoints(); 2989 } 2990 #endif 2991 2992 void InstanceKlass::unload_class(InstanceKlass* ik) { 2993 // Release dependencies. 2994 ik->dependencies().remove_all_dependents(); 2995 2996 // notify the debugger 2997 if (JvmtiExport::should_post_class_unload()) { 2998 JvmtiExport::post_class_unload(ik); 2999 } 3000 3001 // notify ClassLoadingService of class unload 3002 ClassLoadingService::notify_class_unloaded(ik); 3003 3004 SystemDictionaryShared::handle_class_unloading(ik); 3005 3006 if (log_is_enabled(Info, class, unload)) { 3007 ResourceMark rm; 3008 log_info(class, unload)("unloading class %s " PTR_FORMAT, ik->external_name(), p2i(ik)); 3009 } 3010 3011 Events::log_class_unloading(Thread::current(), ik); 3012 3013 #if INCLUDE_JFR 3014 assert(ik != nullptr, "invariant"); 3015 EventClassUnload event; 3016 event.set_unloadedClass(ik); 3017 event.set_definingClassLoader(ik->class_loader_data()); 3018 event.commit(); 3019 #endif 3020 } 3021 3022 static void method_release_C_heap_structures(Method* m) { 3023 m->release_C_heap_structures(); 3024 } 3025 3026 // Called also by InstanceKlass::deallocate_contents, with false for release_sub_metadata. 3027 void InstanceKlass::release_C_heap_structures(bool release_sub_metadata) { 3028 // Clean up C heap 3029 Klass::release_C_heap_structures(); 3030 3031 // Deallocate and call destructors for MDO mutexes 3032 if (release_sub_metadata) { 3033 methods_do(method_release_C_heap_structures); 3034 } 3035 3036 // Destroy the init_monitor 3037 delete _init_monitor; 3038 3039 // Deallocate oop map cache 3040 if (_oop_map_cache != nullptr) { 3041 delete _oop_map_cache; 3042 _oop_map_cache = nullptr; 3043 } 3044 3045 // Deallocate JNI identifiers for jfieldIDs 3046 JNIid::deallocate(jni_ids()); 3047 set_jni_ids(nullptr); 3048 3049 jmethodID* jmeths = methods_jmethod_ids_acquire(); 3050 if (jmeths != (jmethodID*)nullptr) { 3051 release_set_methods_jmethod_ids(nullptr); 3052 FreeHeap(jmeths); 3053 } 3054 3055 assert(_dep_context == nullptr, 3056 "dependencies should already be cleaned"); 3057 3058 #if INCLUDE_JVMTI 3059 // Deallocate breakpoint records 3060 if (breakpoints() != 0x0) { 3061 methods_do(clear_all_breakpoints); 3062 assert(breakpoints() == 0x0, "should have cleared breakpoints"); 3063 } 3064 3065 // deallocate the cached class file 3066 if (_cached_class_file != nullptr) { 3067 os::free(_cached_class_file); 3068 _cached_class_file = nullptr; 3069 } 3070 #endif 3071 3072 FREE_C_HEAP_ARRAY(char, _source_debug_extension); 3073 3074 if (release_sub_metadata) { 3075 constants()->release_C_heap_structures(); 3076 } 3077 } 3078 3079 // The constant pool is on stack if any of the methods are executing or 3080 // referenced by handles. 3081 bool InstanceKlass::on_stack() const { 3082 return _constants->on_stack(); 3083 } 3084 3085 Symbol* InstanceKlass::source_file_name() const { return _constants->source_file_name(); } 3086 u2 InstanceKlass::source_file_name_index() const { return _constants->source_file_name_index(); } 3087 void InstanceKlass::set_source_file_name_index(u2 sourcefile_index) { _constants->set_source_file_name_index(sourcefile_index); } 3088 3089 // minor and major version numbers of class file 3090 u2 InstanceKlass::minor_version() const { return _constants->minor_version(); } 3091 void InstanceKlass::set_minor_version(u2 minor_version) { _constants->set_minor_version(minor_version); } 3092 u2 InstanceKlass::major_version() const { return _constants->major_version(); } 3093 void InstanceKlass::set_major_version(u2 major_version) { _constants->set_major_version(major_version); } 3094 3095 InstanceKlass* InstanceKlass::get_klass_version(int version) { 3096 for (InstanceKlass* ik = this; ik != nullptr; ik = ik->previous_versions()) { 3097 if (ik->constants()->version() == version) { 3098 return ik; 3099 } 3100 } 3101 return nullptr; 3102 } 3103 3104 void InstanceKlass::set_source_debug_extension(const char* array, int length) { 3105 if (array == nullptr) { 3106 _source_debug_extension = nullptr; 3107 } else { 3108 // Adding one to the attribute length in order to store a null terminator 3109 // character could cause an overflow because the attribute length is 3110 // already coded with an u4 in the classfile, but in practice, it's 3111 // unlikely to happen. 3112 assert((length+1) > length, "Overflow checking"); 3113 char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass); 3114 for (int i = 0; i < length; i++) { 3115 sde[i] = array[i]; 3116 } 3117 sde[length] = '\0'; 3118 _source_debug_extension = sde; 3119 } 3120 } 3121 3122 Symbol* InstanceKlass::generic_signature() const { return _constants->generic_signature(); } 3123 u2 InstanceKlass::generic_signature_index() const { return _constants->generic_signature_index(); } 3124 void InstanceKlass::set_generic_signature_index(u2 sig_index) { _constants->set_generic_signature_index(sig_index); } 3125 3126 const char* InstanceKlass::signature_name() const { 3127 return signature_name_of_carrier(JVM_SIGNATURE_CLASS); 3128 } 3129 3130 const char* InstanceKlass::signature_name_of_carrier(char c) const { 3131 // Get the internal name as a c string 3132 const char* src = (const char*) (name()->as_C_string()); 3133 const int src_length = (int)strlen(src); 3134 3135 char* dest = NEW_RESOURCE_ARRAY(char, src_length + 3); 3136 3137 // Add L or Q as type indicator 3138 int dest_index = 0; 3139 dest[dest_index++] = c; 3140 3141 // Add the actual class name 3142 for (int src_index = 0; src_index < src_length; ) { 3143 dest[dest_index++] = src[src_index++]; 3144 } 3145 3146 if (is_hidden()) { // Replace the last '+' with a '.'. 3147 for (int index = (int)src_length; index > 0; index--) { 3148 if (dest[index] == '+') { 3149 dest[index] = JVM_SIGNATURE_DOT; 3150 break; 3151 } 3152 } 3153 } 3154 3155 // Add the semicolon and the null 3156 dest[dest_index++] = JVM_SIGNATURE_ENDCLASS; 3157 dest[dest_index] = '\0'; 3158 return dest; 3159 } 3160 3161 ModuleEntry* InstanceKlass::module() const { 3162 if (is_hidden() && 3163 in_unnamed_package() && 3164 class_loader_data()->has_class_mirror_holder()) { 3165 // For a non-strong hidden class defined to an unnamed package, 3166 // its (class held) CLD will not have an unnamed module created for it. 3167 // Two choices to find the correct ModuleEntry: 3168 // 1. If hidden class is within a nest, use nest host's module 3169 // 2. Find the unnamed module off from the class loader 3170 // For now option #2 is used since a nest host is not set until 3171 // after the instance class is created in jvm_lookup_define_class(). 3172 if (class_loader_data()->is_boot_class_loader_data()) { 3173 return ClassLoaderData::the_null_class_loader_data()->unnamed_module(); 3174 } else { 3175 oop module = java_lang_ClassLoader::unnamedModule(class_loader_data()->class_loader()); 3176 assert(java_lang_Module::is_instance(module), "Not an instance of java.lang.Module"); 3177 return java_lang_Module::module_entry(module); 3178 } 3179 } 3180 3181 // Class is in a named package 3182 if (!in_unnamed_package()) { 3183 return _package_entry->module(); 3184 } 3185 3186 // Class is in an unnamed package, return its loader's unnamed module 3187 return class_loader_data()->unnamed_module(); 3188 } 3189 3190 void InstanceKlass::set_package(ClassLoaderData* loader_data, PackageEntry* pkg_entry, TRAPS) { 3191 3192 // ensure java/ packages only loaded by boot or platform builtin loaders 3193 // not needed for shared class since CDS does not archive prohibited classes. 3194 if (!is_shared()) { 3195 check_prohibited_package(name(), loader_data, CHECK); 3196 } 3197 3198 if (is_shared() && _package_entry != nullptr) { 3199 if (MetaspaceShared::use_full_module_graph() && _package_entry == pkg_entry) { 3200 // we can use the saved package 3201 assert(MetaspaceShared::is_in_shared_metaspace(_package_entry), "must be"); 3202 return; 3203 } else { 3204 _package_entry = nullptr; 3205 } 3206 } 3207 3208 // ClassLoader::package_from_class_name has already incremented the refcount of the symbol 3209 // it returns, so we need to decrement it when the current function exits. 3210 TempNewSymbol from_class_name = 3211 (pkg_entry != nullptr) ? nullptr : ClassLoader::package_from_class_name(name()); 3212 3213 Symbol* pkg_name; 3214 if (pkg_entry != nullptr) { 3215 pkg_name = pkg_entry->name(); 3216 } else { 3217 pkg_name = from_class_name; 3218 } 3219 3220 if (pkg_name != nullptr && loader_data != nullptr) { 3221 3222 // Find in class loader's package entry table. 3223 _package_entry = pkg_entry != nullptr ? pkg_entry : loader_data->packages()->lookup_only(pkg_name); 3224 3225 // If the package name is not found in the loader's package 3226 // entry table, it is an indication that the package has not 3227 // been defined. Consider it defined within the unnamed module. 3228 if (_package_entry == nullptr) { 3229 3230 if (!ModuleEntryTable::javabase_defined()) { 3231 // Before java.base is defined during bootstrapping, define all packages in 3232 // the java.base module. If a non-java.base package is erroneously placed 3233 // in the java.base module it will be caught later when java.base 3234 // is defined by ModuleEntryTable::verify_javabase_packages check. 3235 assert(ModuleEntryTable::javabase_moduleEntry() != nullptr, JAVA_BASE_NAME " module is null"); 3236 _package_entry = loader_data->packages()->create_entry_if_absent(pkg_name, ModuleEntryTable::javabase_moduleEntry()); 3237 } else { 3238 assert(loader_data->unnamed_module() != nullptr, "unnamed module is null"); 3239 _package_entry = loader_data->packages()->create_entry_if_absent(pkg_name, loader_data->unnamed_module()); 3240 } 3241 3242 // A package should have been successfully created 3243 DEBUG_ONLY(ResourceMark rm(THREAD)); 3244 assert(_package_entry != nullptr, "Package entry for class %s not found, loader %s", 3245 name()->as_C_string(), loader_data->loader_name_and_id()); 3246 } 3247 3248 if (log_is_enabled(Debug, module)) { 3249 ResourceMark rm(THREAD); 3250 ModuleEntry* m = _package_entry->module(); 3251 log_trace(module)("Setting package: class: %s, package: %s, loader: %s, module: %s", 3252 external_name(), 3253 pkg_name->as_C_string(), 3254 loader_data->loader_name_and_id(), 3255 (m->is_named() ? m->name()->as_C_string() : UNNAMED_MODULE)); 3256 } 3257 } else { 3258 ResourceMark rm(THREAD); 3259 log_trace(module)("Setting package: class: %s, package: unnamed, loader: %s, module: %s", 3260 external_name(), 3261 (loader_data != nullptr) ? loader_data->loader_name_and_id() : "null", 3262 UNNAMED_MODULE); 3263 } 3264 } 3265 3266 // Function set_classpath_index ensures that for a non-null _package_entry 3267 // of the InstanceKlass, the entry is in the boot loader's package entry table. 3268 // It then sets the classpath_index in the package entry record. 3269 // 3270 // The classpath_index field is used to find the entry on the boot loader class 3271 // path for packages with classes loaded by the boot loader from -Xbootclasspath/a 3272 // in an unnamed module. It is also used to indicate (for all packages whose 3273 // classes are loaded by the boot loader) that at least one of the package's 3274 // classes has been loaded. 3275 void InstanceKlass::set_classpath_index(s2 path_index) { 3276 if (_package_entry != nullptr) { 3277 DEBUG_ONLY(PackageEntryTable* pkg_entry_tbl = ClassLoaderData::the_null_class_loader_data()->packages();) 3278 assert(pkg_entry_tbl->lookup_only(_package_entry->name()) == _package_entry, "Should be same"); 3279 assert(path_index != -1, "Unexpected classpath_index"); 3280 _package_entry->set_classpath_index(path_index); 3281 } 3282 } 3283 3284 // different versions of is_same_class_package 3285 3286 bool InstanceKlass::is_same_class_package(const Klass* class2) const { 3287 oop classloader1 = this->class_loader(); 3288 PackageEntry* classpkg1 = this->package(); 3289 if (class2->is_objArray_klass()) { 3290 class2 = ObjArrayKlass::cast(class2)->bottom_klass(); 3291 } 3292 3293 oop classloader2; 3294 PackageEntry* classpkg2; 3295 if (class2->is_instance_klass()) { 3296 classloader2 = class2->class_loader(); 3297 classpkg2 = class2->package(); 3298 } else { 3299 assert(class2->is_typeArray_klass(), "should be type array"); 3300 classloader2 = nullptr; 3301 classpkg2 = nullptr; 3302 } 3303 3304 // Same package is determined by comparing class loader 3305 // and package entries. Both must be the same. This rule 3306 // applies even to classes that are defined in the unnamed 3307 // package, they still must have the same class loader. 3308 if ((classloader1 == classloader2) && (classpkg1 == classpkg2)) { 3309 return true; 3310 } 3311 3312 return false; 3313 } 3314 3315 // return true if this class and other_class are in the same package. Classloader 3316 // and classname information is enough to determine a class's package 3317 bool InstanceKlass::is_same_class_package(oop other_class_loader, 3318 const Symbol* other_class_name) const { 3319 if (class_loader() != other_class_loader) { 3320 return false; 3321 } 3322 if (name()->fast_compare(other_class_name) == 0) { 3323 return true; 3324 } 3325 3326 { 3327 ResourceMark rm; 3328 3329 bool bad_class_name = false; 3330 TempNewSymbol other_pkg = ClassLoader::package_from_class_name(other_class_name, &bad_class_name); 3331 if (bad_class_name) { 3332 return false; 3333 } 3334 // Check that package_from_class_name() returns null, not "", if there is no package. 3335 assert(other_pkg == nullptr || other_pkg->utf8_length() > 0, "package name is empty string"); 3336 3337 const Symbol* const this_package_name = 3338 this->package() != nullptr ? this->package()->name() : nullptr; 3339 3340 if (this_package_name == nullptr || other_pkg == nullptr) { 3341 // One of the two doesn't have a package. Only return true if the other 3342 // one also doesn't have a package. 3343 return this_package_name == other_pkg; 3344 } 3345 3346 // Check if package is identical 3347 return this_package_name->fast_compare(other_pkg) == 0; 3348 } 3349 } 3350 3351 static bool is_prohibited_package_slow(Symbol* class_name) { 3352 // Caller has ResourceMark 3353 int length; 3354 jchar* unicode = class_name->as_unicode(length); 3355 return (length >= 5 && 3356 unicode[0] == 'j' && 3357 unicode[1] == 'a' && 3358 unicode[2] == 'v' && 3359 unicode[3] == 'a' && 3360 unicode[4] == '/'); 3361 } 3362 3363 // Only boot and platform class loaders can define classes in "java/" packages. 3364 void InstanceKlass::check_prohibited_package(Symbol* class_name, 3365 ClassLoaderData* loader_data, 3366 TRAPS) { 3367 if (!loader_data->is_boot_class_loader_data() && 3368 !loader_data->is_platform_class_loader_data() && 3369 class_name != nullptr && class_name->utf8_length() >= 5) { 3370 ResourceMark rm(THREAD); 3371 bool prohibited; 3372 const u1* base = class_name->base(); 3373 if ((base[0] | base[1] | base[2] | base[3] | base[4]) & 0x80) { 3374 prohibited = is_prohibited_package_slow(class_name); 3375 } else { 3376 char* name = class_name->as_C_string(); 3377 prohibited = (strncmp(name, JAVAPKG, JAVAPKG_LEN) == 0 && name[JAVAPKG_LEN] == '/'); 3378 } 3379 if (prohibited) { 3380 TempNewSymbol pkg_name = ClassLoader::package_from_class_name(class_name); 3381 assert(pkg_name != nullptr, "Error in parsing package name starting with 'java/'"); 3382 char* name = pkg_name->as_C_string(); 3383 const char* class_loader_name = loader_data->loader_name_and_id(); 3384 StringUtils::replace_no_expand(name, "/", "."); 3385 const char* msg_text1 = "Class loader (instance of): "; 3386 const char* msg_text2 = " tried to load prohibited package name: "; 3387 size_t len = strlen(msg_text1) + strlen(class_loader_name) + strlen(msg_text2) + strlen(name) + 1; 3388 char* message = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, len); 3389 jio_snprintf(message, len, "%s%s%s%s", msg_text1, class_loader_name, msg_text2, name); 3390 THROW_MSG(vmSymbols::java_lang_SecurityException(), message); 3391 } 3392 } 3393 return; 3394 } 3395 3396 bool InstanceKlass::find_inner_classes_attr(int* ooff, int* noff, TRAPS) const { 3397 constantPoolHandle i_cp(THREAD, constants()); 3398 for (InnerClassesIterator iter(this); !iter.done(); iter.next()) { 3399 int ioff = iter.inner_class_info_index(); 3400 if (ioff != 0) { 3401 // Check to see if the name matches the class we're looking for 3402 // before attempting to find the class. 3403 if (i_cp->klass_name_at_matches(this, ioff)) { 3404 Klass* inner_klass = i_cp->klass_at(ioff, CHECK_false); 3405 if (this == inner_klass) { 3406 *ooff = iter.outer_class_info_index(); 3407 *noff = iter.inner_name_index(); 3408 return true; 3409 } 3410 } 3411 } 3412 } 3413 return false; 3414 } 3415 3416 InstanceKlass* InstanceKlass::compute_enclosing_class(bool* inner_is_member, TRAPS) const { 3417 InstanceKlass* outer_klass = nullptr; 3418 *inner_is_member = false; 3419 int ooff = 0, noff = 0; 3420 bool has_inner_classes_attr = find_inner_classes_attr(&ooff, &noff, THREAD); 3421 if (has_inner_classes_attr) { 3422 constantPoolHandle i_cp(THREAD, constants()); 3423 if (ooff != 0) { 3424 Klass* ok = i_cp->klass_at(ooff, CHECK_NULL); 3425 if (!ok->is_instance_klass()) { 3426 // If the outer class is not an instance klass then it cannot have 3427 // declared any inner classes. 3428 ResourceMark rm(THREAD); 3429 Exceptions::fthrow( 3430 THREAD_AND_LOCATION, 3431 vmSymbols::java_lang_IncompatibleClassChangeError(), 3432 "%s and %s disagree on InnerClasses attribute", 3433 ok->external_name(), 3434 external_name()); 3435 return nullptr; 3436 } 3437 outer_klass = InstanceKlass::cast(ok); 3438 *inner_is_member = true; 3439 } 3440 if (nullptr == outer_klass) { 3441 // It may be a local class; try for that. 3442 int encl_method_class_idx = enclosing_method_class_index(); 3443 if (encl_method_class_idx != 0) { 3444 Klass* ok = i_cp->klass_at(encl_method_class_idx, CHECK_NULL); 3445 outer_klass = InstanceKlass::cast(ok); 3446 *inner_is_member = false; 3447 } 3448 } 3449 } 3450 3451 // If no inner class attribute found for this class. 3452 if (nullptr == outer_klass) return nullptr; 3453 3454 // Throws an exception if outer klass has not declared k as an inner klass 3455 // We need evidence that each klass knows about the other, or else 3456 // the system could allow a spoof of an inner class to gain access rights. 3457 Reflection::check_for_inner_class(outer_klass, this, *inner_is_member, CHECK_NULL); 3458 return outer_klass; 3459 } 3460 3461 jint InstanceKlass::compute_modifier_flags() const { 3462 jint access = access_flags().as_int(); 3463 3464 // But check if it happens to be member class. 3465 InnerClassesIterator iter(this); 3466 for (; !iter.done(); iter.next()) { 3467 int ioff = iter.inner_class_info_index(); 3468 // Inner class attribute can be zero, skip it. 3469 // Strange but true: JVM spec. allows null inner class refs. 3470 if (ioff == 0) continue; 3471 3472 // only look at classes that are already loaded 3473 // since we are looking for the flags for our self. 3474 Symbol* inner_name = constants()->klass_name_at(ioff); 3475 if (name() == inner_name) { 3476 // This is really a member class. 3477 access = iter.inner_access_flags(); 3478 break; 3479 } 3480 } 3481 return (access & JVM_ACC_WRITTEN_FLAGS); 3482 } 3483 3484 jint InstanceKlass::jvmti_class_status() const { 3485 jint result = 0; 3486 3487 if (is_linked()) { 3488 result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED; 3489 } 3490 3491 if (is_initialized()) { 3492 assert(is_linked(), "Class status is not consistent"); 3493 result |= JVMTI_CLASS_STATUS_INITIALIZED; 3494 } 3495 if (is_in_error_state()) { 3496 result |= JVMTI_CLASS_STATUS_ERROR; 3497 } 3498 return result; 3499 } 3500 3501 Method* InstanceKlass::method_at_itable(InstanceKlass* holder, int index, TRAPS) { 3502 bool implements_interface; // initialized by method_at_itable_or_null 3503 Method* m = method_at_itable_or_null(holder, index, 3504 implements_interface); // out parameter 3505 if (m != nullptr) { 3506 assert(implements_interface, "sanity"); 3507 return m; 3508 } else if (implements_interface) { 3509 // Throw AbstractMethodError since corresponding itable slot is empty. 3510 THROW_NULL(vmSymbols::java_lang_AbstractMethodError()); 3511 } else { 3512 // If the interface isn't implemented by the receiver class, 3513 // the VM should throw IncompatibleClassChangeError. 3514 ResourceMark rm(THREAD); 3515 stringStream ss; 3516 bool same_module = (module() == holder->module()); 3517 ss.print("Receiver class %s does not implement " 3518 "the interface %s defining the method to be called " 3519 "(%s%s%s)", 3520 external_name(), holder->external_name(), 3521 (same_module) ? joint_in_module_of_loader(holder) : class_in_module_of_loader(), 3522 (same_module) ? "" : "; ", 3523 (same_module) ? "" : holder->class_in_module_of_loader()); 3524 THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), ss.as_string()); 3525 } 3526 } 3527 3528 Method* InstanceKlass::method_at_itable_or_null(InstanceKlass* holder, int index, bool& implements_interface) { 3529 klassItable itable(this); 3530 for (int i = 0; i < itable.size_offset_table(); i++) { 3531 itableOffsetEntry* offset_entry = itable.offset_entry(i); 3532 if (offset_entry->interface_klass() == holder) { 3533 implements_interface = true; 3534 itableMethodEntry* ime = offset_entry->first_method_entry(this); 3535 Method* m = ime[index].method(); 3536 return m; 3537 } 3538 } 3539 implements_interface = false; 3540 return nullptr; // offset entry not found 3541 } 3542 3543 int InstanceKlass::vtable_index_of_interface_method(Method* intf_method) { 3544 assert(is_linked(), "required"); 3545 assert(intf_method->method_holder()->is_interface(), "not an interface method"); 3546 assert(is_subtype_of(intf_method->method_holder()), "interface not implemented"); 3547 3548 int vtable_index = Method::invalid_vtable_index; 3549 Symbol* name = intf_method->name(); 3550 Symbol* signature = intf_method->signature(); 3551 3552 // First check in default method array 3553 if (!intf_method->is_abstract() && default_methods() != nullptr) { 3554 int index = find_method_index(default_methods(), 3555 name, signature, 3556 Klass::OverpassLookupMode::find, 3557 Klass::StaticLookupMode::find, 3558 Klass::PrivateLookupMode::find); 3559 if (index >= 0) { 3560 vtable_index = default_vtable_indices()->at(index); 3561 } 3562 } 3563 if (vtable_index == Method::invalid_vtable_index) { 3564 // get vtable_index for miranda methods 3565 klassVtable vt = vtable(); 3566 vtable_index = vt.index_of_miranda(name, signature); 3567 } 3568 return vtable_index; 3569 } 3570 3571 #if INCLUDE_JVMTI 3572 // update default_methods for redefineclasses for methods that are 3573 // not yet in the vtable due to concurrent subclass define and superinterface 3574 // redefinition 3575 // Note: those in the vtable, should have been updated via adjust_method_entries 3576 void InstanceKlass::adjust_default_methods(bool* trace_name_printed) { 3577 // search the default_methods for uses of either obsolete or EMCP methods 3578 if (default_methods() != nullptr) { 3579 for (int index = 0; index < default_methods()->length(); index ++) { 3580 Method* old_method = default_methods()->at(index); 3581 if (old_method == nullptr || !old_method->is_old()) { 3582 continue; // skip uninteresting entries 3583 } 3584 assert(!old_method->is_deleted(), "default methods may not be deleted"); 3585 Method* new_method = old_method->get_new_method(); 3586 default_methods()->at_put(index, new_method); 3587 3588 if (log_is_enabled(Info, redefine, class, update)) { 3589 ResourceMark rm; 3590 if (!(*trace_name_printed)) { 3591 log_info(redefine, class, update) 3592 ("adjust: klassname=%s default methods from name=%s", 3593 external_name(), old_method->method_holder()->external_name()); 3594 *trace_name_printed = true; 3595 } 3596 log_debug(redefine, class, update, vtables) 3597 ("default method update: %s(%s) ", 3598 new_method->name()->as_C_string(), new_method->signature()->as_C_string()); 3599 } 3600 } 3601 } 3602 } 3603 #endif // INCLUDE_JVMTI 3604 3605 // On-stack replacement stuff 3606 void InstanceKlass::add_osr_nmethod(nmethod* n) { 3607 assert_lock_strong(CompiledMethod_lock); 3608 #ifndef PRODUCT 3609 nmethod* prev = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), n->comp_level(), true); 3610 assert(prev == nullptr || !prev->is_in_use() COMPILER2_PRESENT(|| StressRecompilation), 3611 "redundant OSR recompilation detected. memory leak in CodeCache!"); 3612 #endif 3613 // only one compilation can be active 3614 assert(n->is_osr_method(), "wrong kind of nmethod"); 3615 n->set_osr_link(osr_nmethods_head()); 3616 set_osr_nmethods_head(n); 3617 // Raise the highest osr level if necessary 3618 n->method()->set_highest_osr_comp_level(MAX2(n->method()->highest_osr_comp_level(), n->comp_level())); 3619 3620 // Get rid of the osr methods for the same bci that have lower levels. 3621 for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) { 3622 nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true); 3623 if (inv != nullptr && inv->is_in_use()) { 3624 inv->make_not_entrant(); 3625 } 3626 } 3627 } 3628 3629 // Remove osr nmethod from the list. Return true if found and removed. 3630 bool InstanceKlass::remove_osr_nmethod(nmethod* n) { 3631 // This is a short non-blocking critical region, so the no safepoint check is ok. 3632 MutexLocker ml(CompiledMethod_lock->owned_by_self() ? nullptr : CompiledMethod_lock 3633 , Mutex::_no_safepoint_check_flag); 3634 assert(n->is_osr_method(), "wrong kind of nmethod"); 3635 nmethod* last = nullptr; 3636 nmethod* cur = osr_nmethods_head(); 3637 int max_level = CompLevel_none; // Find the max comp level excluding n 3638 Method* m = n->method(); 3639 // Search for match 3640 bool found = false; 3641 while(cur != nullptr && cur != n) { 3642 if (m == cur->method()) { 3643 // Find max level before n 3644 max_level = MAX2(max_level, cur->comp_level()); 3645 } 3646 last = cur; 3647 cur = cur->osr_link(); 3648 } 3649 nmethod* next = nullptr; 3650 if (cur == n) { 3651 found = true; 3652 next = cur->osr_link(); 3653 if (last == nullptr) { 3654 // Remove first element 3655 set_osr_nmethods_head(next); 3656 } else { 3657 last->set_osr_link(next); 3658 } 3659 } 3660 n->set_osr_link(nullptr); 3661 cur = next; 3662 while (cur != nullptr) { 3663 // Find max level after n 3664 if (m == cur->method()) { 3665 max_level = MAX2(max_level, cur->comp_level()); 3666 } 3667 cur = cur->osr_link(); 3668 } 3669 m->set_highest_osr_comp_level(max_level); 3670 return found; 3671 } 3672 3673 int InstanceKlass::mark_osr_nmethods(DeoptimizationScope* deopt_scope, const Method* m) { 3674 MutexLocker ml(CompiledMethod_lock->owned_by_self() ? nullptr : CompiledMethod_lock, 3675 Mutex::_no_safepoint_check_flag); 3676 nmethod* osr = osr_nmethods_head(); 3677 int found = 0; 3678 while (osr != nullptr) { 3679 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain"); 3680 if (osr->method() == m) { 3681 deopt_scope->mark(osr); 3682 found++; 3683 } 3684 osr = osr->osr_link(); 3685 } 3686 return found; 3687 } 3688 3689 nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const { 3690 MutexLocker ml(CompiledMethod_lock->owned_by_self() ? nullptr : CompiledMethod_lock, 3691 Mutex::_no_safepoint_check_flag); 3692 nmethod* osr = osr_nmethods_head(); 3693 nmethod* best = nullptr; 3694 while (osr != nullptr) { 3695 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain"); 3696 // There can be a time when a c1 osr method exists but we are waiting 3697 // for a c2 version. When c2 completes its osr nmethod we will trash 3698 // the c1 version and only be able to find the c2 version. However 3699 // while we overflow in the c1 code at back branches we don't want to 3700 // try and switch to the same code as we are already running 3701 3702 if (osr->method() == m && 3703 (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) { 3704 if (match_level) { 3705 if (osr->comp_level() == comp_level) { 3706 // Found a match - return it. 3707 return osr; 3708 } 3709 } else { 3710 if (best == nullptr || (osr->comp_level() > best->comp_level())) { 3711 if (osr->comp_level() == CompilationPolicy::highest_compile_level()) { 3712 // Found the best possible - return it. 3713 return osr; 3714 } 3715 best = osr; 3716 } 3717 } 3718 } 3719 osr = osr->osr_link(); 3720 } 3721 3722 assert(match_level == false || best == nullptr, "shouldn't pick up anything if match_level is set"); 3723 if (best != nullptr && best->comp_level() >= comp_level) { 3724 return best; 3725 } 3726 return nullptr; 3727 } 3728 3729 // ----------------------------------------------------------------------------------------------------- 3730 // Printing 3731 3732 #define BULLET " - " 3733 3734 static const char* state_names[] = { 3735 "allocated", "loaded", "being_linked", "linked", "being_initialized", "fully_initialized", "initialization_error" 3736 }; 3737 3738 static void print_vtable(address self, intptr_t* start, int len, outputStream* st) { 3739 ResourceMark rm; 3740 int* forward_refs = NEW_RESOURCE_ARRAY(int, len); 3741 for (int i = 0; i < len; i++) forward_refs[i] = 0; 3742 for (int i = 0; i < len; i++) { 3743 intptr_t e = start[i]; 3744 st->print("%d : " INTPTR_FORMAT, i, e); 3745 if (forward_refs[i] != 0) { 3746 int from = forward_refs[i]; 3747 int off = (int) start[from]; 3748 st->print(" (offset %d <= [%d])", off, from); 3749 } 3750 if (MetaspaceObj::is_valid((Metadata*)e)) { 3751 st->print(" "); 3752 ((Metadata*)e)->print_value_on(st); 3753 } else if (self != nullptr && e > 0 && e < 0x10000) { 3754 address location = self + e; 3755 int index = (int)((intptr_t*)location - start); 3756 st->print(" (offset %d => [%d])", (int)e, index); 3757 if (index >= 0 && index < len) 3758 forward_refs[index] = i; 3759 } 3760 st->cr(); 3761 } 3762 } 3763 3764 static void print_vtable(vtableEntry* start, int len, outputStream* st) { 3765 return print_vtable(nullptr, reinterpret_cast<intptr_t*>(start), len, st); 3766 } 3767 3768 template<typename T> 3769 static void print_array_on(outputStream* st, Array<T>* array) { 3770 if (array == nullptr) { st->print_cr("nullptr"); return; } 3771 array->print_value_on(st); st->cr(); 3772 if (Verbose || WizardMode) { 3773 for (int i = 0; i < array->length(); i++) { 3774 st->print("%d : ", i); array->at(i)->print_value_on(st); st->cr(); 3775 } 3776 } 3777 } 3778 3779 static void print_array_on(outputStream* st, Array<int>* array) { 3780 if (array == nullptr) { st->print_cr("nullptr"); return; } 3781 array->print_value_on(st); st->cr(); 3782 if (Verbose || WizardMode) { 3783 for (int i = 0; i < array->length(); i++) { 3784 st->print("%d : %d", i, array->at(i)); st->cr(); 3785 } 3786 } 3787 } 3788 3789 const char* InstanceKlass::init_state_name() const { 3790 return state_names[init_state()]; 3791 } 3792 3793 void InstanceKlass::print_on(outputStream* st) const { 3794 assert(is_klass(), "must be klass"); 3795 Klass::print_on(st); 3796 3797 st->print(BULLET"instance size: %d", size_helper()); st->cr(); 3798 st->print(BULLET"klass size: %d", size()); st->cr(); 3799 st->print(BULLET"access: "); access_flags().print_on(st); st->cr(); 3800 st->print(BULLET"flags: "); _misc_flags.print_on(st); st->cr(); 3801 st->print(BULLET"state: "); st->print_cr("%s", init_state_name()); 3802 st->print(BULLET"name: "); name()->print_value_on(st); st->cr(); 3803 st->print(BULLET"super: "); Metadata::print_value_on_maybe_null(st, super()); st->cr(); 3804 st->print(BULLET"sub: "); 3805 Klass* sub = subklass(); 3806 int n; 3807 for (n = 0; sub != nullptr; n++, sub = sub->next_sibling()) { 3808 if (n < MaxSubklassPrintSize) { 3809 sub->print_value_on(st); 3810 st->print(" "); 3811 } 3812 } 3813 if (n >= MaxSubklassPrintSize) st->print("(" INTX_FORMAT " more klasses...)", n - MaxSubklassPrintSize); 3814 st->cr(); 3815 3816 if (is_interface()) { 3817 st->print_cr(BULLET"nof implementors: %d", nof_implementors()); 3818 if (nof_implementors() == 1) { 3819 st->print_cr(BULLET"implementor: "); 3820 st->print(" "); 3821 implementor()->print_value_on(st); 3822 st->cr(); 3823 } 3824 } 3825 3826 st->print(BULLET"arrays: "); Metadata::print_value_on_maybe_null(st, array_klasses()); st->cr(); 3827 st->print(BULLET"methods: "); print_array_on(st, methods()); 3828 st->print(BULLET"method ordering: "); print_array_on(st, method_ordering()); 3829 st->print(BULLET"default_methods: "); print_array_on(st, default_methods()); 3830 if (default_vtable_indices() != nullptr) { 3831 st->print(BULLET"default vtable indices: "); print_array_on(st, default_vtable_indices()); 3832 } 3833 st->print(BULLET"local interfaces: "); print_array_on(st, local_interfaces()); 3834 st->print(BULLET"trans. interfaces: "); print_array_on(st, transitive_interfaces()); 3835 st->print(BULLET"constants: "); constants()->print_value_on(st); st->cr(); 3836 if (class_loader_data() != nullptr) { 3837 st->print(BULLET"class loader data: "); 3838 class_loader_data()->print_value_on(st); 3839 st->cr(); 3840 } 3841 if (source_file_name() != nullptr) { 3842 st->print(BULLET"source file: "); 3843 source_file_name()->print_value_on(st); 3844 st->cr(); 3845 } 3846 if (source_debug_extension() != nullptr) { 3847 st->print(BULLET"source debug extension: "); 3848 st->print("%s", source_debug_extension()); 3849 st->cr(); 3850 } 3851 st->print(BULLET"class annotations: "); class_annotations()->print_value_on(st); st->cr(); 3852 st->print(BULLET"class type annotations: "); class_type_annotations()->print_value_on(st); st->cr(); 3853 st->print(BULLET"field annotations: "); fields_annotations()->print_value_on(st); st->cr(); 3854 st->print(BULLET"field type annotations: "); fields_type_annotations()->print_value_on(st); st->cr(); 3855 { 3856 bool have_pv = false; 3857 // previous versions are linked together through the InstanceKlass 3858 for (InstanceKlass* pv_node = previous_versions(); 3859 pv_node != nullptr; 3860 pv_node = pv_node->previous_versions()) { 3861 if (!have_pv) 3862 st->print(BULLET"previous version: "); 3863 have_pv = true; 3864 pv_node->constants()->print_value_on(st); 3865 } 3866 if (have_pv) st->cr(); 3867 } 3868 3869 if (generic_signature() != nullptr) { 3870 st->print(BULLET"generic signature: "); 3871 generic_signature()->print_value_on(st); 3872 st->cr(); 3873 } 3874 st->print(BULLET"inner classes: "); inner_classes()->print_value_on(st); st->cr(); 3875 st->print(BULLET"nest members: "); nest_members()->print_value_on(st); st->cr(); 3876 if (record_components() != nullptr) { 3877 st->print(BULLET"record components: "); record_components()->print_value_on(st); st->cr(); 3878 } 3879 st->print(BULLET"permitted subclasses: "); permitted_subclasses()->print_value_on(st); st->cr(); 3880 st->print(BULLET"preload classes: "); preload_classes()->print_value_on(st); st->cr(); 3881 if (java_mirror() != nullptr) { 3882 st->print(BULLET"java mirror: "); 3883 java_mirror()->print_value_on(st); 3884 st->cr(); 3885 } else { 3886 st->print_cr(BULLET"java mirror: null"); 3887 } 3888 st->print(BULLET"vtable length %d (start addr: " PTR_FORMAT ")", vtable_length(), p2i(start_of_vtable())); st->cr(); 3889 if (vtable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_vtable(), vtable_length(), st); 3890 st->print(BULLET"itable length %d (start addr: " PTR_FORMAT ")", itable_length(), p2i(start_of_itable())); st->cr(); 3891 if (itable_length() > 0 && (Verbose || WizardMode)) print_vtable(nullptr, start_of_itable(), itable_length(), st); 3892 st->print_cr(BULLET"---- static fields (%d words):", static_field_size()); 3893 FieldPrinter print_static_field(st); 3894 ((InstanceKlass*)this)->do_local_static_fields(&print_static_field); 3895 st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size()); 3896 FieldPrinter print_nonstatic_field(st); 3897 InstanceKlass* ik = const_cast<InstanceKlass*>(this); 3898 ik->print_nonstatic_fields(&print_nonstatic_field); 3899 3900 st->print(BULLET"non-static oop maps: "); 3901 OopMapBlock* map = start_of_nonstatic_oop_maps(); 3902 OopMapBlock* end_map = map + nonstatic_oop_map_count(); 3903 while (map < end_map) { 3904 st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1)); 3905 map++; 3906 } 3907 st->cr(); 3908 } 3909 3910 void InstanceKlass::print_value_on(outputStream* st) const { 3911 assert(is_klass(), "must be klass"); 3912 if (Verbose || WizardMode) access_flags().print_on(st); 3913 name()->print_value_on(st); 3914 } 3915 3916 void FieldPrinter::do_field(fieldDescriptor* fd) { 3917 _st->print(BULLET); 3918 if (_obj == nullptr) { 3919 fd->print_on(_st); 3920 _st->cr(); 3921 } else { 3922 fd->print_on_for(_st, _obj); 3923 _st->cr(); 3924 } 3925 } 3926 3927 3928 void InstanceKlass::oop_print_on(oop obj, outputStream* st) { 3929 Klass::oop_print_on(obj, st); 3930 3931 if (this == vmClasses::String_klass()) { 3932 typeArrayOop value = java_lang_String::value(obj); 3933 juint length = java_lang_String::length(obj); 3934 if (value != nullptr && 3935 value->is_typeArray() && 3936 length <= (juint) value->length()) { 3937 st->print(BULLET"string: "); 3938 java_lang_String::print(obj, st); 3939 st->cr(); 3940 } 3941 } 3942 3943 st->print_cr(BULLET"---- fields (total size " SIZE_FORMAT " words):", oop_size(obj)); 3944 FieldPrinter print_field(st, obj); 3945 print_nonstatic_fields(&print_field); 3946 3947 if (this == vmClasses::Class_klass()) { 3948 st->print(BULLET"signature: "); 3949 java_lang_Class::print_signature(obj, st); 3950 st->cr(); 3951 Klass* real_klass = java_lang_Class::as_Klass(obj); 3952 if (real_klass != nullptr && real_klass->is_instance_klass()) { 3953 st->print_cr(BULLET"---- static fields (%d):", java_lang_Class::static_oop_field_count(obj)); 3954 InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field); 3955 } 3956 } else if (this == vmClasses::MethodType_klass()) { 3957 st->print(BULLET"signature: "); 3958 java_lang_invoke_MethodType::print_signature(obj, st); 3959 st->cr(); 3960 } 3961 } 3962 3963 #ifndef PRODUCT 3964 3965 bool InstanceKlass::verify_itable_index(int i) { 3966 int method_count = klassItable::method_count_for_interface(this); 3967 assert(i >= 0 && i < method_count, "index out of bounds"); 3968 return true; 3969 } 3970 3971 #endif //PRODUCT 3972 3973 void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) { 3974 st->print("a "); 3975 name()->print_value_on(st); 3976 obj->print_address_on(st); 3977 if (this == vmClasses::String_klass() 3978 && java_lang_String::value(obj) != nullptr) { 3979 ResourceMark rm; 3980 int len = java_lang_String::length(obj); 3981 int plen = (len < 24 ? len : 12); 3982 char* str = java_lang_String::as_utf8_string(obj, 0, plen); 3983 st->print(" = \"%s\"", str); 3984 if (len > plen) 3985 st->print("...[%d]", len); 3986 } else if (this == vmClasses::Class_klass()) { 3987 Klass* k = java_lang_Class::as_Klass(obj); 3988 st->print(" = "); 3989 if (k != nullptr) { 3990 k->print_value_on(st); 3991 } else { 3992 const char* tname = type2name(java_lang_Class::primitive_type(obj)); 3993 st->print("%s", tname ? tname : "type?"); 3994 } 3995 } else if (this == vmClasses::MethodType_klass()) { 3996 st->print(" = "); 3997 java_lang_invoke_MethodType::print_signature(obj, st); 3998 } else if (java_lang_boxing_object::is_instance(obj)) { 3999 st->print(" = "); 4000 java_lang_boxing_object::print(obj, st); 4001 } else if (this == vmClasses::LambdaForm_klass()) { 4002 oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj); 4003 if (vmentry != nullptr) { 4004 st->print(" => "); 4005 vmentry->print_value_on(st); 4006 } 4007 } else if (this == vmClasses::MemberName_klass()) { 4008 Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj); 4009 if (vmtarget != nullptr) { 4010 st->print(" = "); 4011 vmtarget->print_value_on(st); 4012 } else { 4013 oop clazz = java_lang_invoke_MemberName::clazz(obj); 4014 oop name = java_lang_invoke_MemberName::name(obj); 4015 if (clazz != nullptr) { 4016 clazz->print_value_on(st); 4017 } else { 4018 st->print("null"); 4019 } 4020 st->print("."); 4021 if (name != nullptr) { 4022 name->print_value_on(st); 4023 } else { 4024 st->print("null"); 4025 } 4026 } 4027 } 4028 } 4029 4030 const char* InstanceKlass::internal_name() const { 4031 return external_name(); 4032 } 4033 4034 void InstanceKlass::print_class_load_logging(ClassLoaderData* loader_data, 4035 const ModuleEntry* module_entry, 4036 const ClassFileStream* cfs) const { 4037 4038 if (ClassListWriter::is_enabled()) { 4039 ClassListWriter::write(this, cfs); 4040 } 4041 4042 print_class_load_helper(loader_data, module_entry, cfs); 4043 print_class_load_cause_logging(); 4044 } 4045 4046 void InstanceKlass::print_class_load_helper(ClassLoaderData* loader_data, 4047 const ModuleEntry* module_entry, 4048 const ClassFileStream* cfs) const { 4049 4050 if (!log_is_enabled(Info, class, load)) { 4051 return; 4052 } 4053 4054 ResourceMark rm; 4055 LogMessage(class, load) msg; 4056 stringStream info_stream; 4057 4058 // Name and class hierarchy info 4059 info_stream.print("%s", external_name()); 4060 4061 // Source 4062 if (cfs != nullptr) { 4063 if (cfs->source() != nullptr) { 4064 const char* module_name = (module_entry->name() == nullptr) ? UNNAMED_MODULE : module_entry->name()->as_C_string(); 4065 if (module_name != nullptr) { 4066 // When the boot loader created the stream, it didn't know the module name 4067 // yet. Let's format it now. 4068 if (cfs->from_boot_loader_modules_image()) { 4069 info_stream.print(" source: jrt:/%s", module_name); 4070 } else { 4071 info_stream.print(" source: %s", cfs->source()); 4072 } 4073 } else { 4074 info_stream.print(" source: %s", cfs->source()); 4075 } 4076 } else if (loader_data == ClassLoaderData::the_null_class_loader_data()) { 4077 Thread* current = Thread::current(); 4078 Klass* caller = current->is_Java_thread() ? 4079 JavaThread::cast(current)->security_get_caller_class(1): 4080 nullptr; 4081 // caller can be null, for example, during a JVMTI VM_Init hook 4082 if (caller != nullptr) { 4083 info_stream.print(" source: instance of %s", caller->external_name()); 4084 } else { 4085 // source is unknown 4086 } 4087 } else { 4088 oop class_loader = loader_data->class_loader(); 4089 info_stream.print(" source: %s", class_loader->klass()->external_name()); 4090 } 4091 } else { 4092 assert(this->is_shared(), "must be"); 4093 if (MetaspaceShared::is_shared_dynamic((void*)this)) { 4094 info_stream.print(" source: shared objects file (top)"); 4095 } else { 4096 info_stream.print(" source: shared objects file"); 4097 } 4098 } 4099 4100 msg.info("%s", info_stream.as_string()); 4101 4102 if (log_is_enabled(Debug, class, load)) { 4103 stringStream debug_stream; 4104 4105 // Class hierarchy info 4106 debug_stream.print(" klass: " PTR_FORMAT " super: " PTR_FORMAT, 4107 p2i(this), p2i(superklass())); 4108 4109 // Interfaces 4110 if (local_interfaces() != nullptr && local_interfaces()->length() > 0) { 4111 debug_stream.print(" interfaces:"); 4112 int length = local_interfaces()->length(); 4113 for (int i = 0; i < length; i++) { 4114 debug_stream.print(" " PTR_FORMAT, 4115 p2i(InstanceKlass::cast(local_interfaces()->at(i)))); 4116 } 4117 } 4118 4119 // Class loader 4120 debug_stream.print(" loader: ["); 4121 loader_data->print_value_on(&debug_stream); 4122 debug_stream.print("]"); 4123 4124 // Classfile checksum 4125 if (cfs) { 4126 debug_stream.print(" bytes: %d checksum: %08x", 4127 cfs->length(), 4128 ClassLoader::crc32(0, (const char*)cfs->buffer(), 4129 cfs->length())); 4130 } 4131 4132 msg.debug("%s", debug_stream.as_string()); 4133 } 4134 } 4135 4136 void InstanceKlass::print_class_load_cause_logging() const { 4137 bool log_cause_native = log_is_enabled(Info, class, load, cause, native); 4138 if (log_cause_native || log_is_enabled(Info, class, load, cause)) { 4139 JavaThread* current = JavaThread::current(); 4140 ResourceMark rm(current); 4141 const char* name = external_name(); 4142 4143 if (LogClassLoadingCauseFor == nullptr || 4144 (strcmp("*", LogClassLoadingCauseFor) != 0 && 4145 strstr(name, LogClassLoadingCauseFor) == nullptr)) { 4146 return; 4147 } 4148 4149 // Log Java stack first 4150 { 4151 LogMessage(class, load, cause) msg; 4152 NonInterleavingLogStream info_stream{LogLevelType::Info, msg}; 4153 4154 info_stream.print_cr("Java stack when loading %s:", name); 4155 current->print_stack_on(&info_stream); 4156 } 4157 4158 // Log native stack second 4159 if (log_cause_native) { 4160 // Log to string first so that lines can be indented 4161 stringStream stack_stream; 4162 char buf[O_BUFLEN]; 4163 address lastpc = nullptr; 4164 if (os::platform_print_native_stack(&stack_stream, nullptr, buf, O_BUFLEN, lastpc)) { 4165 // We have printed the native stack in platform-specific code, 4166 // so nothing else to do in this case. 4167 } else { 4168 frame f = os::current_frame(); 4169 VMError::print_native_stack(&stack_stream, f, current, true /*print_source_info */, 4170 -1 /* max stack_stream */, buf, O_BUFLEN); 4171 } 4172 4173 LogMessage(class, load, cause, native) msg; 4174 NonInterleavingLogStream info_stream{LogLevelType::Info, msg}; 4175 info_stream.print_cr("Native stack when loading %s:", name); 4176 4177 // Print each native stack line to the log 4178 int size = (int) stack_stream.size(); 4179 char* stack = stack_stream.as_string(); 4180 char* stack_end = stack + size; 4181 char* line_start = stack; 4182 for (char* p = stack; p < stack_end; p++) { 4183 if (*p == '\n') { 4184 *p = '\0'; 4185 info_stream.print_cr("\t%s", line_start); 4186 line_start = p + 1; 4187 } 4188 } 4189 if (line_start < stack_end) { 4190 info_stream.print_cr("\t%s", line_start); 4191 } 4192 } 4193 } 4194 } 4195 4196 // Verification 4197 4198 class VerifyFieldClosure: public BasicOopIterateClosure { 4199 protected: 4200 template <class T> void do_oop_work(T* p) { 4201 oop obj = RawAccess<>::oop_load(p); 4202 if (!oopDesc::is_oop_or_null(obj)) { 4203 tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p2i(p), p2i(obj)); 4204 Universe::print_on(tty); 4205 guarantee(false, "boom"); 4206 } 4207 } 4208 public: 4209 virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); } 4210 virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); } 4211 }; 4212 4213 void InstanceKlass::verify_on(outputStream* st) { 4214 #ifndef PRODUCT 4215 // Avoid redundant verifies, this really should be in product. 4216 if (_verify_count == Universe::verify_count()) return; 4217 _verify_count = Universe::verify_count(); 4218 #endif 4219 4220 // Verify Klass 4221 Klass::verify_on(st); 4222 4223 // Verify that klass is present in ClassLoaderData 4224 guarantee(class_loader_data()->contains_klass(this), 4225 "this class isn't found in class loader data"); 4226 4227 // Verify vtables 4228 if (is_linked()) { 4229 // $$$ This used to be done only for m/s collections. Doing it 4230 // always seemed a valid generalization. (DLD -- 6/00) 4231 vtable().verify(st); 4232 } 4233 4234 // Verify first subklass 4235 if (subklass() != nullptr) { 4236 guarantee(subklass()->is_klass(), "should be klass"); 4237 } 4238 4239 // Verify siblings 4240 Klass* super = this->super(); 4241 Klass* sib = next_sibling(); 4242 if (sib != nullptr) { 4243 if (sib == this) { 4244 fatal("subclass points to itself " PTR_FORMAT, p2i(sib)); 4245 } 4246 4247 guarantee(sib->is_klass(), "should be klass"); 4248 guarantee(sib->super() == super, "siblings should have same superklass"); 4249 } 4250 4251 // Verify local interfaces 4252 if (local_interfaces()) { 4253 Array<InstanceKlass*>* local_interfaces = this->local_interfaces(); 4254 for (int j = 0; j < local_interfaces->length(); j++) { 4255 InstanceKlass* e = local_interfaces->at(j); 4256 guarantee(e->is_klass() && e->is_interface(), "invalid local interface"); 4257 } 4258 } 4259 4260 // Verify transitive interfaces 4261 if (transitive_interfaces() != nullptr) { 4262 Array<InstanceKlass*>* transitive_interfaces = this->transitive_interfaces(); 4263 for (int j = 0; j < transitive_interfaces->length(); j++) { 4264 InstanceKlass* e = transitive_interfaces->at(j); 4265 guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface"); 4266 } 4267 } 4268 4269 // Verify methods 4270 if (methods() != nullptr) { 4271 Array<Method*>* methods = this->methods(); 4272 for (int j = 0; j < methods->length(); j++) { 4273 guarantee(methods->at(j)->is_method(), "non-method in methods array"); 4274 } 4275 for (int j = 0; j < methods->length() - 1; j++) { 4276 Method* m1 = methods->at(j); 4277 Method* m2 = methods->at(j + 1); 4278 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly"); 4279 } 4280 } 4281 4282 // Verify method ordering 4283 if (method_ordering() != nullptr) { 4284 Array<int>* method_ordering = this->method_ordering(); 4285 int length = method_ordering->length(); 4286 if (JvmtiExport::can_maintain_original_method_order() || 4287 ((UseSharedSpaces || Arguments::is_dumping_archive()) && length != 0)) { 4288 guarantee(length == methods()->length(), "invalid method ordering length"); 4289 jlong sum = 0; 4290 for (int j = 0; j < length; j++) { 4291 int original_index = method_ordering->at(j); 4292 guarantee(original_index >= 0, "invalid method ordering index"); 4293 guarantee(original_index < length, "invalid method ordering index"); 4294 sum += original_index; 4295 } 4296 // Verify sum of indices 0,1,...,length-1 4297 guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum"); 4298 } else { 4299 guarantee(length == 0, "invalid method ordering length"); 4300 } 4301 } 4302 4303 // Verify default methods 4304 if (default_methods() != nullptr) { 4305 Array<Method*>* methods = this->default_methods(); 4306 for (int j = 0; j < methods->length(); j++) { 4307 guarantee(methods->at(j)->is_method(), "non-method in methods array"); 4308 } 4309 for (int j = 0; j < methods->length() - 1; j++) { 4310 Method* m1 = methods->at(j); 4311 Method* m2 = methods->at(j + 1); 4312 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly"); 4313 } 4314 } 4315 4316 // Verify JNI static field identifiers 4317 if (jni_ids() != nullptr) { 4318 jni_ids()->verify(this); 4319 } 4320 4321 // Verify other fields 4322 if (constants() != nullptr) { 4323 guarantee(constants()->is_constantPool(), "should be constant pool"); 4324 } 4325 } 4326 4327 void InstanceKlass::oop_verify_on(oop obj, outputStream* st) { 4328 Klass::oop_verify_on(obj, st); 4329 VerifyFieldClosure blk; 4330 obj->oop_iterate(&blk); 4331 } 4332 4333 4334 // JNIid class for jfieldIDs only 4335 // Note to reviewers: 4336 // These JNI functions are just moved over to column 1 and not changed 4337 // in the compressed oops workspace. 4338 JNIid::JNIid(Klass* holder, int offset, JNIid* next) { 4339 _holder = holder; 4340 _offset = offset; 4341 _next = next; 4342 debug_only(_is_static_field_id = false;) 4343 } 4344 4345 4346 JNIid* JNIid::find(int offset) { 4347 JNIid* current = this; 4348 while (current != nullptr) { 4349 if (current->offset() == offset) return current; 4350 current = current->next(); 4351 } 4352 return nullptr; 4353 } 4354 4355 void JNIid::deallocate(JNIid* current) { 4356 while (current != nullptr) { 4357 JNIid* next = current->next(); 4358 delete current; 4359 current = next; 4360 } 4361 } 4362 4363 4364 void JNIid::verify(Klass* holder) { 4365 int first_field_offset = InstanceMirrorKlass::offset_of_static_fields(); 4366 int end_field_offset; 4367 end_field_offset = first_field_offset + (InstanceKlass::cast(holder)->static_field_size() * wordSize); 4368 4369 JNIid* current = this; 4370 while (current != nullptr) { 4371 guarantee(current->holder() == holder, "Invalid klass in JNIid"); 4372 #ifdef ASSERT 4373 int o = current->offset(); 4374 if (current->is_static_field_id()) { 4375 guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid"); 4376 } 4377 #endif 4378 current = current->next(); 4379 } 4380 } 4381 4382 void InstanceKlass::set_init_state(ClassState state) { 4383 if (state > loaded) { 4384 assert_lock_strong(_init_monitor); 4385 } 4386 #ifdef ASSERT 4387 bool good_state = is_shared() ? (_init_state <= state) 4388 : (_init_state < state); 4389 bool link_failed = _init_state == being_linked && state == loaded; 4390 assert(good_state || state == allocated || link_failed, "illegal state transition"); 4391 #endif 4392 assert(_init_thread == nullptr, "should be cleared before state change"); 4393 Atomic::store(&_init_state, state); 4394 } 4395 4396 #if INCLUDE_JVMTI 4397 4398 // RedefineClasses() support for previous versions 4399 4400 // Globally, there is at least one previous version of a class to walk 4401 // during class unloading, which is saved because old methods in the class 4402 // are still running. Otherwise the previous version list is cleaned up. 4403 bool InstanceKlass::_should_clean_previous_versions = false; 4404 4405 // Returns true if there are previous versions of a class for class 4406 // unloading only. Also resets the flag to false. purge_previous_version 4407 // will set the flag to true if there are any left, i.e., if there's any 4408 // work to do for next time. This is to avoid the expensive code cache 4409 // walk in CLDG::clean_deallocate_lists(). 4410 bool InstanceKlass::should_clean_previous_versions_and_reset() { 4411 bool ret = _should_clean_previous_versions; 4412 log_trace(redefine, class, iklass, purge)("Class unloading: should_clean_previous_versions = %s", 4413 ret ? "true" : "false"); 4414 _should_clean_previous_versions = false; 4415 return ret; 4416 } 4417 4418 // Purge previous versions before adding new previous versions of the class and 4419 // during class unloading. 4420 void InstanceKlass::purge_previous_version_list() { 4421 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint"); 4422 assert(has_been_redefined(), "Should only be called for main class"); 4423 4424 // Quick exit. 4425 if (previous_versions() == nullptr) { 4426 return; 4427 } 4428 4429 // This klass has previous versions so see what we can cleanup 4430 // while it is safe to do so. 4431 4432 int deleted_count = 0; // leave debugging breadcrumbs 4433 int live_count = 0; 4434 ClassLoaderData* loader_data = class_loader_data(); 4435 assert(loader_data != nullptr, "should never be null"); 4436 4437 ResourceMark rm; 4438 log_trace(redefine, class, iklass, purge)("%s: previous versions", external_name()); 4439 4440 // previous versions are linked together through the InstanceKlass 4441 InstanceKlass* pv_node = previous_versions(); 4442 InstanceKlass* last = this; 4443 int version = 0; 4444 4445 // check the previous versions list 4446 for (; pv_node != nullptr; ) { 4447 4448 ConstantPool* pvcp = pv_node->constants(); 4449 assert(pvcp != nullptr, "cp ref was unexpectedly cleared"); 4450 4451 if (!pvcp->on_stack()) { 4452 // If the constant pool isn't on stack, none of the methods 4453 // are executing. Unlink this previous_version. 4454 // The previous version InstanceKlass is on the ClassLoaderData deallocate list 4455 // so will be deallocated during the next phase of class unloading. 4456 log_trace(redefine, class, iklass, purge) 4457 ("previous version " PTR_FORMAT " is dead.", p2i(pv_node)); 4458 // Unlink from previous version list. 4459 assert(pv_node->class_loader_data() == loader_data, "wrong loader_data"); 4460 InstanceKlass* next = pv_node->previous_versions(); 4461 pv_node->link_previous_versions(nullptr); // point next to null 4462 last->link_previous_versions(next); 4463 // Delete this node directly. Nothing is referring to it and we don't 4464 // want it to increase the counter for metadata to delete in CLDG. 4465 MetadataFactory::free_metadata(loader_data, pv_node); 4466 pv_node = next; 4467 deleted_count++; 4468 version++; 4469 continue; 4470 } else { 4471 assert(pvcp->pool_holder() != nullptr, "Constant pool with no holder"); 4472 guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack"); 4473 live_count++; 4474 if (pvcp->is_shared()) { 4475 // Shared previous versions can never be removed so no cleaning is needed. 4476 log_trace(redefine, class, iklass, purge)("previous version " PTR_FORMAT " is shared", p2i(pv_node)); 4477 } else { 4478 // Previous version alive, set that clean is needed for next time. 4479 _should_clean_previous_versions = true; 4480 log_trace(redefine, class, iklass, purge)("previous version " PTR_FORMAT " is alive", p2i(pv_node)); 4481 } 4482 } 4483 4484 // next previous version 4485 last = pv_node; 4486 pv_node = pv_node->previous_versions(); 4487 version++; 4488 } 4489 log_trace(redefine, class, iklass, purge) 4490 ("previous version stats: live=%d, deleted=%d", live_count, deleted_count); 4491 } 4492 4493 void InstanceKlass::mark_newly_obsolete_methods(Array<Method*>* old_methods, 4494 int emcp_method_count) { 4495 int obsolete_method_count = old_methods->length() - emcp_method_count; 4496 4497 if (emcp_method_count != 0 && obsolete_method_count != 0 && 4498 _previous_versions != nullptr) { 4499 // We have a mix of obsolete and EMCP methods so we have to 4500 // clear out any matching EMCP method entries the hard way. 4501 int local_count = 0; 4502 for (int i = 0; i < old_methods->length(); i++) { 4503 Method* old_method = old_methods->at(i); 4504 if (old_method->is_obsolete()) { 4505 // only obsolete methods are interesting 4506 Symbol* m_name = old_method->name(); 4507 Symbol* m_signature = old_method->signature(); 4508 4509 // previous versions are linked together through the InstanceKlass 4510 int j = 0; 4511 for (InstanceKlass* prev_version = _previous_versions; 4512 prev_version != nullptr; 4513 prev_version = prev_version->previous_versions(), j++) { 4514 4515 Array<Method*>* method_refs = prev_version->methods(); 4516 for (int k = 0; k < method_refs->length(); k++) { 4517 Method* method = method_refs->at(k); 4518 4519 if (!method->is_obsolete() && 4520 method->name() == m_name && 4521 method->signature() == m_signature) { 4522 // The current RedefineClasses() call has made all EMCP 4523 // versions of this method obsolete so mark it as obsolete 4524 log_trace(redefine, class, iklass, add) 4525 ("%s(%s): flush obsolete method @%d in version @%d", 4526 m_name->as_C_string(), m_signature->as_C_string(), k, j); 4527 4528 method->set_is_obsolete(); 4529 break; 4530 } 4531 } 4532 4533 // The previous loop may not find a matching EMCP method, but 4534 // that doesn't mean that we can optimize and not go any 4535 // further back in the PreviousVersion generations. The EMCP 4536 // method for this generation could have already been made obsolete, 4537 // but there still may be an older EMCP method that has not 4538 // been made obsolete. 4539 } 4540 4541 if (++local_count >= obsolete_method_count) { 4542 // no more obsolete methods so bail out now 4543 break; 4544 } 4545 } 4546 } 4547 } 4548 } 4549 4550 // Save the scratch_class as the previous version if any of the methods are running. 4551 // The previous_versions are used to set breakpoints in EMCP methods and they are 4552 // also used to clean MethodData links to redefined methods that are no longer running. 4553 void InstanceKlass::add_previous_version(InstanceKlass* scratch_class, 4554 int emcp_method_count) { 4555 assert(Thread::current()->is_VM_thread(), 4556 "only VMThread can add previous versions"); 4557 4558 ResourceMark rm; 4559 log_trace(redefine, class, iklass, add) 4560 ("adding previous version ref for %s, EMCP_cnt=%d", scratch_class->external_name(), emcp_method_count); 4561 4562 // Clean out old previous versions for this class 4563 purge_previous_version_list(); 4564 4565 // Mark newly obsolete methods in remaining previous versions. An EMCP method from 4566 // a previous redefinition may be made obsolete by this redefinition. 4567 Array<Method*>* old_methods = scratch_class->methods(); 4568 mark_newly_obsolete_methods(old_methods, emcp_method_count); 4569 4570 // If the constant pool for this previous version of the class 4571 // is not marked as being on the stack, then none of the methods 4572 // in this previous version of the class are on the stack so 4573 // we don't need to add this as a previous version. 4574 ConstantPool* cp_ref = scratch_class->constants(); 4575 if (!cp_ref->on_stack()) { 4576 log_trace(redefine, class, iklass, add)("scratch class not added; no methods are running"); 4577 scratch_class->class_loader_data()->add_to_deallocate_list(scratch_class); 4578 return; 4579 } 4580 4581 // Add previous version if any methods are still running or if this is 4582 // a shared class which should never be removed. 4583 assert(scratch_class->previous_versions() == nullptr, "shouldn't have a previous version"); 4584 scratch_class->link_previous_versions(previous_versions()); 4585 link_previous_versions(scratch_class); 4586 if (cp_ref->is_shared()) { 4587 log_trace(redefine, class, iklass, add) ("scratch class added; class is shared"); 4588 } else { 4589 // We only set clean_previous_versions flag for processing during class 4590 // unloading for non-shared classes. 4591 _should_clean_previous_versions = true; 4592 log_trace(redefine, class, iklass, add) ("scratch class added; one of its methods is on_stack."); 4593 } 4594 } // end add_previous_version() 4595 4596 #endif // INCLUDE_JVMTI 4597 4598 Method* InstanceKlass::method_with_idnum(int idnum) { 4599 Method* m = nullptr; 4600 if (idnum < methods()->length()) { 4601 m = methods()->at(idnum); 4602 } 4603 if (m == nullptr || m->method_idnum() != idnum) { 4604 for (int index = 0; index < methods()->length(); ++index) { 4605 m = methods()->at(index); 4606 if (m->method_idnum() == idnum) { 4607 return m; 4608 } 4609 } 4610 // None found, return null for the caller to handle. 4611 return nullptr; 4612 } 4613 return m; 4614 } 4615 4616 4617 Method* InstanceKlass::method_with_orig_idnum(int idnum) { 4618 if (idnum >= methods()->length()) { 4619 return nullptr; 4620 } 4621 Method* m = methods()->at(idnum); 4622 if (m != nullptr && m->orig_method_idnum() == idnum) { 4623 return m; 4624 } 4625 // Obsolete method idnum does not match the original idnum 4626 for (int index = 0; index < methods()->length(); ++index) { 4627 m = methods()->at(index); 4628 if (m->orig_method_idnum() == idnum) { 4629 return m; 4630 } 4631 } 4632 // None found, return null for the caller to handle. 4633 return nullptr; 4634 } 4635 4636 4637 Method* InstanceKlass::method_with_orig_idnum(int idnum, int version) { 4638 InstanceKlass* holder = get_klass_version(version); 4639 if (holder == nullptr) { 4640 return nullptr; // The version of klass is gone, no method is found 4641 } 4642 Method* method = holder->method_with_orig_idnum(idnum); 4643 return method; 4644 } 4645 4646 #if INCLUDE_JVMTI 4647 JvmtiCachedClassFileData* InstanceKlass::get_cached_class_file() { 4648 return _cached_class_file; 4649 } 4650 4651 jint InstanceKlass::get_cached_class_file_len() { 4652 return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file); 4653 } 4654 4655 unsigned char * InstanceKlass::get_cached_class_file_bytes() { 4656 return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file); 4657 } 4658 #endif 4659 4660 // Make a step iterating over the class hierarchy under the root class. 4661 // Skips subclasses if requested. 4662 void ClassHierarchyIterator::next() { 4663 assert(_current != nullptr, "required"); 4664 if (_visit_subclasses && _current->subklass() != nullptr) { 4665 _current = _current->subklass(); 4666 return; // visit next subclass 4667 } 4668 _visit_subclasses = true; // reset 4669 while (_current->next_sibling() == nullptr && _current != _root) { 4670 _current = _current->superklass(); // backtrack; no more sibling subclasses left 4671 } 4672 if (_current == _root) { 4673 // Iteration is over (back at root after backtracking). Invalidate the iterator. 4674 _current = nullptr; 4675 return; 4676 } 4677 _current = _current->next_sibling(); 4678 return; // visit next sibling subclass 4679 } 4680