1 /* 2 * Copyright (c) 1997, 2020, 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 "jvm.h" 27 #include "aot/aotLoader.hpp" 28 #include "classfile/classFileParser.hpp" 29 #include "classfile/classFileStream.hpp" 30 #include "classfile/classLoader.hpp" 31 #include "classfile/classLoaderData.inline.hpp" 32 #include "classfile/javaClasses.hpp" 33 #include "classfile/moduleEntry.hpp" 34 #include "classfile/resolutionErrors.hpp" 35 #include "classfile/symbolTable.hpp" 36 #include "classfile/systemDictionary.hpp" 37 #include "classfile/systemDictionaryShared.hpp" 38 #include "classfile/verifier.hpp" 39 #include "classfile/vmSymbols.hpp" 40 #include "code/dependencyContext.hpp" 41 #include "compiler/compileBroker.hpp" 42 #include "gc/shared/collectedHeap.inline.hpp" 43 #include "interpreter/oopMapCache.hpp" 44 #include "interpreter/rewriter.hpp" 45 #include "jvmtifiles/jvmti.h" 46 #include "logging/log.hpp" 47 #include "logging/logMessage.hpp" 48 #include "logging/logStream.hpp" 49 #include "memory/allocation.inline.hpp" 50 #include "memory/iterator.inline.hpp" 51 #include "memory/metadataFactory.hpp" 52 #include "memory/metaspaceClosure.hpp" 53 #include "memory/metaspaceShared.hpp" 54 #include "memory/oopFactory.hpp" 55 #include "memory/resourceArea.hpp" 56 #include "memory/universe.hpp" 57 #include "oops/fieldStreams.inline.hpp" 58 #include "oops/constantPool.hpp" 59 #include "oops/instanceClassLoaderKlass.hpp" 60 #include "oops/instanceKlass.inline.hpp" 61 #include "oops/instanceMirrorKlass.hpp" 62 #include "oops/instanceOop.hpp" 63 #include "oops/klass.inline.hpp" 64 #include "oops/method.hpp" 65 #include "oops/oop.inline.hpp" 66 #include "oops/recordComponent.hpp" 67 #include "oops/symbol.hpp" 68 #include "prims/jvmtiExport.hpp" 69 #include "prims/jvmtiRedefineClasses.hpp" 70 #include "prims/jvmtiThreadState.hpp" 71 #include "prims/methodComparator.hpp" 72 #include "runtime/atomic.hpp" 73 #include "runtime/biasedLocking.hpp" 74 #include "runtime/fieldDescriptor.inline.hpp" 75 #include "runtime/handles.inline.hpp" 76 #include "runtime/javaCalls.hpp" 77 #include "runtime/mutexLocker.hpp" 78 #include "runtime/orderAccess.hpp" 79 #include "runtime/thread.inline.hpp" 80 #include "services/classLoadingService.hpp" 81 #include "services/threadService.hpp" 82 #include "utilities/dtrace.hpp" 83 #include "utilities/events.hpp" 84 #include "utilities/macros.hpp" 85 #include "utilities/stringUtils.hpp" 86 #ifdef COMPILER1 87 #include "c1/c1_Compiler.hpp" 88 #endif 89 #if INCLUDE_JFR 90 #include "jfr/jfrEvents.hpp" 91 #endif 92 93 94 #ifdef DTRACE_ENABLED 95 96 97 #define HOTSPOT_CLASS_INITIALIZATION_required HOTSPOT_CLASS_INITIALIZATION_REQUIRED 98 #define HOTSPOT_CLASS_INITIALIZATION_recursive HOTSPOT_CLASS_INITIALIZATION_RECURSIVE 99 #define HOTSPOT_CLASS_INITIALIZATION_concurrent HOTSPOT_CLASS_INITIALIZATION_CONCURRENT 100 #define HOTSPOT_CLASS_INITIALIZATION_erroneous HOTSPOT_CLASS_INITIALIZATION_ERRONEOUS 101 #define HOTSPOT_CLASS_INITIALIZATION_super__failed HOTSPOT_CLASS_INITIALIZATION_SUPER_FAILED 102 #define HOTSPOT_CLASS_INITIALIZATION_clinit HOTSPOT_CLASS_INITIALIZATION_CLINIT 103 #define HOTSPOT_CLASS_INITIALIZATION_error HOTSPOT_CLASS_INITIALIZATION_ERROR 104 #define HOTSPOT_CLASS_INITIALIZATION_end HOTSPOT_CLASS_INITIALIZATION_END 105 #define DTRACE_CLASSINIT_PROBE(type, thread_type) \ 106 { \ 107 char* data = NULL; \ 108 int len = 0; \ 109 Symbol* clss_name = name(); \ 110 if (clss_name != NULL) { \ 111 data = (char*)clss_name->bytes(); \ 112 len = clss_name->utf8_length(); \ 113 } \ 114 HOTSPOT_CLASS_INITIALIZATION_##type( \ 115 data, len, (void*)class_loader(), thread_type); \ 116 } 117 118 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait) \ 119 { \ 120 char* data = NULL; \ 121 int len = 0; \ 122 Symbol* clss_name = name(); \ 123 if (clss_name != NULL) { \ 124 data = (char*)clss_name->bytes(); \ 125 len = clss_name->utf8_length(); \ 126 } \ 127 HOTSPOT_CLASS_INITIALIZATION_##type( \ 128 data, len, (void*)class_loader(), thread_type, wait); \ 129 } 130 131 #else // ndef DTRACE_ENABLED 132 133 #define DTRACE_CLASSINIT_PROBE(type, thread_type) 134 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait) 135 136 #endif // ndef DTRACE_ENABLED 137 138 139 static inline bool is_class_loader(const Symbol* class_name, 140 const ClassFileParser& parser) { 141 assert(class_name != NULL, "invariant"); 142 143 if (class_name == vmSymbols::java_lang_ClassLoader()) { 144 return true; 145 } 146 147 if (SystemDictionary::ClassLoader_klass_loaded()) { 148 const Klass* const super_klass = parser.super_klass(); 149 if (super_klass != NULL) { 150 if (super_klass->is_subtype_of(SystemDictionary::ClassLoader_klass())) { 151 return true; 152 } 153 } 154 } 155 return false; 156 } 157 158 // private: called to verify that k is a static member of this nest. 159 // We know that k is an instance class in the same package and hence the 160 // same classloader. 161 bool InstanceKlass::has_nest_member(InstanceKlass* k, TRAPS) const { 162 assert(!is_hidden(), "unexpected hidden class"); 163 if (_nest_members == NULL || _nest_members == Universe::the_empty_short_array()) { 164 if (log_is_enabled(Trace, class, nestmates)) { 165 ResourceMark rm(THREAD); 166 log_trace(class, nestmates)("Checked nest membership of %s in non-nest-host class %s", 167 k->external_name(), this->external_name()); 168 } 169 return false; 170 } 171 172 if (log_is_enabled(Trace, class, nestmates)) { 173 ResourceMark rm(THREAD); 174 log_trace(class, nestmates)("Checking nest membership of %s in %s", 175 k->external_name(), this->external_name()); 176 } 177 178 // Check for a resolved cp entry , else fall back to a name check. 179 // We don't want to resolve any class other than the one being checked. 180 for (int i = 0; i < _nest_members->length(); i++) { 181 int cp_index = _nest_members->at(i); 182 if (_constants->tag_at(cp_index).is_klass()) { 183 Klass* k2 = _constants->klass_at(cp_index, THREAD); 184 assert(!HAS_PENDING_EXCEPTION || PENDING_EXCEPTION->is_a(SystemDictionary::VirtualMachineError_klass()), 185 "Exceptions should not be possible here"); 186 if (k2 == k) { 187 log_trace(class, nestmates)("- class is listed at nest_members[%d] => cp[%d]", i, cp_index); 188 return true; 189 } 190 } 191 else { 192 Symbol* name = _constants->klass_name_at(cp_index); 193 if (name == k->name()) { 194 log_trace(class, nestmates)("- Found it at nest_members[%d] => cp[%d]", i, cp_index); 195 196 // Names match so check actual klass. This may trigger class loading if 197 // it doesn't match though that should be impossible as it means one classloader 198 // has defined two different classes with the same name! A compiler thread won't be 199 // able to perform that loading but we can't exclude the compiler threads from 200 // executing this logic. But it should actually be impossible to trigger loading here. 201 Klass* k2 = _constants->klass_at(cp_index, THREAD); 202 assert(!HAS_PENDING_EXCEPTION || PENDING_EXCEPTION->is_a(SystemDictionary::VirtualMachineError_klass()), 203 "Exceptions should not be possible here"); 204 if (k2 == k) { 205 log_trace(class, nestmates)("- class is listed as a nest member"); 206 return true; 207 } 208 else { 209 // same name but different klass! 210 log_trace(class, nestmates)(" - klass comparison failed!"); 211 // can't have two names the same, so we're done 212 return false; 213 } 214 } 215 } 216 } 217 log_trace(class, nestmates)("- class is NOT a nest member!"); 218 return false; 219 } 220 221 // Return nest-host class, resolving, validating and saving it if needed. 222 // In cases where this is called from a thread that cannot do classloading 223 // (such as a native JIT thread) then we simply return NULL, which in turn 224 // causes the access check to return false. Such code will retry the access 225 // from a more suitable environment later. Otherwise the _nest_host is always 226 // set once this method returns. 227 // Any errors from nest-host resolution must be preserved so they can be queried 228 // from higher-level access checking code, and reported as part of access checking 229 // exceptions. 230 // VirtualMachineErrors are propagated with a NULL return. 231 // Under any conditions where the _nest_host can be set to non-NULL the resulting 232 // value of it and, if applicable, the nest host resolution/validation error, 233 // are idempotent. 234 InstanceKlass* InstanceKlass::nest_host(TRAPS) { 235 InstanceKlass* nest_host_k = _nest_host; 236 if (nest_host_k != NULL) { 237 return nest_host_k; 238 } 239 240 ResourceMark rm(THREAD); 241 242 // need to resolve and save our nest-host class. 243 if (_nest_host_index != 0) { // we have a real nest_host 244 // Before trying to resolve check if we're in a suitable context 245 if (!THREAD->can_call_java() && !_constants->tag_at(_nest_host_index).is_klass()) { 246 log_trace(class, nestmates)("Rejected resolution of nest-host of %s in unsuitable thread", 247 this->external_name()); 248 return NULL; // sentinel to say "try again from a different context" 249 } 250 251 log_trace(class, nestmates)("Resolving nest-host of %s using cp entry for %s", 252 this->external_name(), 253 _constants->klass_name_at(_nest_host_index)->as_C_string()); 254 255 Klass* k = _constants->klass_at(_nest_host_index, THREAD); 256 if (HAS_PENDING_EXCEPTION) { 257 if (PENDING_EXCEPTION->is_a(SystemDictionary::VirtualMachineError_klass())) { 258 return NULL; // propagate VMEs 259 } 260 stringStream ss; 261 char* target_host_class = _constants->klass_name_at(_nest_host_index)->as_C_string(); 262 ss.print("Nest host resolution of %s with host %s failed: ", 263 this->external_name(), target_host_class); 264 java_lang_Throwable::print(PENDING_EXCEPTION, &ss); 265 const char* msg = ss.as_string(true /* on C-heap */); 266 constantPoolHandle cph(THREAD, constants()); 267 SystemDictionary::add_nest_host_error(cph, _nest_host_index, msg); 268 CLEAR_PENDING_EXCEPTION; 269 270 log_trace(class, nestmates)("%s", msg); 271 } else { 272 // A valid nest-host is an instance class in the current package that lists this 273 // class as a nest member. If any of these conditions are not met the class is 274 // its own nest-host. 275 const char* error = NULL; 276 277 // JVMS 5.4.4 indicates package check comes first 278 if (is_same_class_package(k)) { 279 // Now check actual membership. We can't be a member if our "host" is 280 // not an instance class. 281 if (k->is_instance_klass()) { 282 nest_host_k = InstanceKlass::cast(k); 283 bool is_member = nest_host_k->has_nest_member(this, THREAD); 284 // exception is rare, perhaps impossible 285 if (!HAS_PENDING_EXCEPTION) { 286 if (is_member) { 287 _nest_host = nest_host_k; // save resolved nest-host value 288 289 log_trace(class, nestmates)("Resolved nest-host of %s to %s", 290 this->external_name(), k->external_name()); 291 return nest_host_k; 292 } else { 293 error = "current type is not listed as a nest member"; 294 } 295 } else { 296 if (PENDING_EXCEPTION->is_a(SystemDictionary::VirtualMachineError_klass())) { 297 return NULL; // propagate VMEs 298 } 299 stringStream ss; 300 ss.print("exception on member check: "); 301 java_lang_Throwable::print(PENDING_EXCEPTION, &ss); 302 error = ss.as_string(); 303 } 304 } else { 305 error = "host is not an instance class"; 306 } 307 } else { 308 error = "types are in different packages"; 309 } 310 311 // something went wrong, so record what and log it 312 { 313 stringStream ss; 314 ss.print("Type %s (loader: %s) is not a nest member of type %s (loader: %s): %s", 315 this->external_name(), 316 this->class_loader_data()->loader_name_and_id(), 317 k->external_name(), 318 k->class_loader_data()->loader_name_and_id(), 319 error); 320 const char* msg = ss.as_string(true /* on C-heap */); 321 constantPoolHandle cph(THREAD, constants()); 322 SystemDictionary::add_nest_host_error(cph, _nest_host_index, msg); 323 log_trace(class, nestmates)("%s", msg); 324 } 325 } 326 } else { 327 log_trace(class, nestmates)("Type %s is not part of a nest: setting nest-host to self", 328 this->external_name()); 329 } 330 331 // Either not in an explicit nest, or else an error occurred, so 332 // the nest-host is set to `this`. Any thread that sees this assignment 333 // will also see any setting of nest_host_error(), if applicable. 334 return (_nest_host = this); 335 } 336 337 // Dynamic nest member support: set this class's nest host to the given class. 338 // This occurs as part of the class definition, as soon as the instanceKlass 339 // has been created and doesn't require further resolution. The code: 340 // lookup().defineHiddenClass(bytes_for_X, NESTMATE); 341 // results in: 342 // class_of_X.set_nest_host(lookup().lookupClass().getNestHost()) 343 // If it has an explicit _nest_host_index or _nest_members, these will be ignored. 344 // We also know the "host" is a valid nest-host in the same package so we can 345 // assert some of those facts. 346 void InstanceKlass::set_nest_host(InstanceKlass* host, TRAPS) { 347 assert(is_hidden(), "must be a hidden class"); 348 assert(host != NULL, "NULL nest host specified"); 349 assert(_nest_host == NULL, "current class has resolved nest-host"); 350 assert(nest_host_error(THREAD) == NULL, "unexpected nest host resolution error exists: %s", 351 nest_host_error(THREAD)); 352 assert((host->_nest_host == NULL && host->_nest_host_index == 0) || 353 (host->_nest_host == host), "proposed host is not a valid nest-host"); 354 // Can't assert this as package is not set yet: 355 // assert(is_same_class_package(host), "proposed host is in wrong package"); 356 357 if (log_is_enabled(Trace, class, nestmates)) { 358 ResourceMark rm(THREAD); 359 const char* msg = ""; 360 // a hidden class does not expect a statically defined nest-host 361 if (_nest_host_index > 0) { 362 msg = "(the NestHost attribute in the current class is ignored)"; 363 } else if (_nest_members != NULL && _nest_members != Universe::the_empty_short_array()) { 364 msg = "(the NestMembers attribute in the current class is ignored)"; 365 } 366 log_trace(class, nestmates)("Injected type %s into the nest of %s %s", 367 this->external_name(), 368 host->external_name(), 369 msg); 370 } 371 // set dynamic nest host 372 _nest_host = host; 373 // Record dependency to keep nest host from being unloaded before this class. 374 ClassLoaderData* this_key = class_loader_data(); 375 this_key->record_dependency(host); 376 } 377 378 // check if 'this' and k are nestmates (same nest_host), or k is our nest_host, 379 // or we are k's nest_host - all of which is covered by comparing the two 380 // resolved_nest_hosts. 381 // Any exceptions (i.e. VMEs) are propagated. 382 bool InstanceKlass::has_nestmate_access_to(InstanceKlass* k, TRAPS) { 383 384 assert(this != k, "this should be handled by higher-level code"); 385 386 // Per JVMS 5.4.4 we first resolve and validate the current class, then 387 // the target class k. 388 389 InstanceKlass* cur_host = nest_host(CHECK_false); 390 if (cur_host == NULL) { 391 return false; 392 } 393 394 Klass* k_nest_host = k->nest_host(CHECK_false); 395 if (k_nest_host == NULL) { 396 return false; 397 } 398 399 bool access = (cur_host == k_nest_host); 400 401 ResourceMark rm(THREAD); 402 log_trace(class, nestmates)("Class %s does %shave nestmate access to %s", 403 this->external_name(), 404 access ? "" : "NOT ", 405 k->external_name()); 406 return access; 407 } 408 409 const char* InstanceKlass::nest_host_error(TRAPS) { 410 if (_nest_host_index == 0) { 411 return NULL; 412 } else { 413 constantPoolHandle cph(THREAD, constants()); 414 return SystemDictionary::find_nest_host_error(cph, (int)_nest_host_index); 415 } 416 } 417 418 InstanceKlass* InstanceKlass::allocate_instance_klass(const ClassFileParser& parser, TRAPS) { 419 bool is_hidden_or_anonymous = parser.is_hidden() || parser.is_unsafe_anonymous(); 420 const int size = InstanceKlass::size(parser.vtable_size(), 421 parser.itable_size(), 422 nonstatic_oop_map_size(parser.total_oop_map_count()), 423 parser.is_interface(), 424 parser.is_unsafe_anonymous(), 425 should_store_fingerprint(is_hidden_or_anonymous)); 426 427 const Symbol* const class_name = parser.class_name(); 428 assert(class_name != NULL, "invariant"); 429 ClassLoaderData* loader_data = parser.loader_data(); 430 assert(loader_data != NULL, "invariant"); 431 432 InstanceKlass* ik; 433 434 // Allocation 435 if (REF_NONE == parser.reference_type()) { 436 if (class_name == vmSymbols::java_lang_Class()) { 437 // mirror 438 ik = new (loader_data, size, THREAD) InstanceMirrorKlass(parser); 439 } 440 else if (is_class_loader(class_name, parser)) { 441 // class loader 442 ik = new (loader_data, size, THREAD) InstanceClassLoaderKlass(parser); 443 } else { 444 // normal 445 ik = new (loader_data, size, THREAD) InstanceKlass(parser, InstanceKlass::_kind_other); 446 } 447 } else { 448 // reference 449 ik = new (loader_data, size, THREAD) InstanceRefKlass(parser); 450 } 451 452 // Check for pending exception before adding to the loader data and incrementing 453 // class count. Can get OOM here. 454 if (HAS_PENDING_EXCEPTION) { 455 return NULL; 456 } 457 458 return ik; 459 } 460 461 462 // copy method ordering from resource area to Metaspace 463 void InstanceKlass::copy_method_ordering(const intArray* m, TRAPS) { 464 if (m != NULL) { 465 // allocate a new array and copy contents (memcpy?) 466 _method_ordering = MetadataFactory::new_array<int>(class_loader_data(), m->length(), CHECK); 467 for (int i = 0; i < m->length(); i++) { 468 _method_ordering->at_put(i, m->at(i)); 469 } 470 } else { 471 _method_ordering = Universe::the_empty_int_array(); 472 } 473 } 474 475 // create a new array of vtable_indices for default methods 476 Array<int>* InstanceKlass::create_new_default_vtable_indices(int len, TRAPS) { 477 Array<int>* vtable_indices = MetadataFactory::new_array<int>(class_loader_data(), len, CHECK_NULL); 478 assert(default_vtable_indices() == NULL, "only create once"); 479 set_default_vtable_indices(vtable_indices); 480 return vtable_indices; 481 } 482 483 InstanceKlass::InstanceKlass(const ClassFileParser& parser, unsigned kind, KlassID id) : 484 Klass(id), 485 _nest_members(NULL), 486 _nest_host(NULL), 487 _record_components(NULL), 488 _static_field_size(parser.static_field_size()), 489 _nonstatic_oop_map_size(nonstatic_oop_map_size(parser.total_oop_map_count())), 490 _itable_len(parser.itable_size()), 491 _nest_host_index(0), 492 _init_state(allocated), 493 _reference_type(parser.reference_type()), 494 _init_thread(NULL) 495 { 496 set_vtable_length(parser.vtable_size()); 497 set_kind(kind); 498 set_access_flags(parser.access_flags()); 499 if (parser.is_hidden()) set_is_hidden(); 500 set_is_unsafe_anonymous(parser.is_unsafe_anonymous()); 501 set_layout_helper(Klass::instance_layout_helper(parser.layout_size(), 502 false)); 503 504 assert(NULL == _methods, "underlying memory not zeroed?"); 505 assert(is_instance_klass(), "is layout incorrect?"); 506 assert(size_helper() == parser.layout_size(), "incorrect size_helper?"); 507 508 if (Arguments::is_dumping_archive()) { 509 SystemDictionaryShared::init_dumptime_info(this); 510 } 511 512 // Set biased locking bit for all instances of this class; it will be 513 // cleared if revocation occurs too often for this type 514 if (UseBiasedLocking && BiasedLocking::enabled()) { 515 set_prototype_header(markWord::biased_locking_prototype()); 516 } 517 } 518 519 void InstanceKlass::deallocate_methods(ClassLoaderData* loader_data, 520 Array<Method*>* methods) { 521 if (methods != NULL && methods != Universe::the_empty_method_array() && 522 !methods->is_shared()) { 523 for (int i = 0; i < methods->length(); i++) { 524 Method* method = methods->at(i); 525 if (method == NULL) continue; // maybe null if error processing 526 // Only want to delete methods that are not executing for RedefineClasses. 527 // The previous version will point to them so they're not totally dangling 528 assert (!method->on_stack(), "shouldn't be called with methods on stack"); 529 MetadataFactory::free_metadata(loader_data, method); 530 } 531 MetadataFactory::free_array<Method*>(loader_data, methods); 532 } 533 } 534 535 void InstanceKlass::deallocate_interfaces(ClassLoaderData* loader_data, 536 const Klass* super_klass, 537 Array<InstanceKlass*>* local_interfaces, 538 Array<InstanceKlass*>* transitive_interfaces) { 539 // Only deallocate transitive interfaces if not empty, same as super class 540 // or same as local interfaces. See code in parseClassFile. 541 Array<InstanceKlass*>* ti = transitive_interfaces; 542 if (ti != Universe::the_empty_instance_klass_array() && ti != local_interfaces) { 543 // check that the interfaces don't come from super class 544 Array<InstanceKlass*>* sti = (super_klass == NULL) ? NULL : 545 InstanceKlass::cast(super_klass)->transitive_interfaces(); 546 if (ti != sti && ti != NULL && !ti->is_shared()) { 547 MetadataFactory::free_array<InstanceKlass*>(loader_data, ti); 548 } 549 } 550 551 // local interfaces can be empty 552 if (local_interfaces != Universe::the_empty_instance_klass_array() && 553 local_interfaces != NULL && !local_interfaces->is_shared()) { 554 MetadataFactory::free_array<InstanceKlass*>(loader_data, local_interfaces); 555 } 556 } 557 558 void InstanceKlass::deallocate_record_components(ClassLoaderData* loader_data, 559 Array<RecordComponent*>* record_components) { 560 if (record_components != NULL && !record_components->is_shared()) { 561 for (int i = 0; i < record_components->length(); i++) { 562 RecordComponent* record_component = record_components->at(i); 563 MetadataFactory::free_metadata(loader_data, record_component); 564 } 565 MetadataFactory::free_array<RecordComponent*>(loader_data, record_components); 566 } 567 } 568 569 // This function deallocates the metadata and C heap pointers that the 570 // InstanceKlass points to. 571 void InstanceKlass::deallocate_contents(ClassLoaderData* loader_data) { 572 573 // Orphan the mirror first, CMS thinks it's still live. 574 if (java_mirror() != NULL) { 575 java_lang_Class::set_klass(java_mirror(), NULL); 576 } 577 578 // Also remove mirror from handles 579 loader_data->remove_handle(_java_mirror); 580 581 // Need to take this class off the class loader data list. 582 loader_data->remove_class(this); 583 584 // The array_klass for this class is created later, after error handling. 585 // For class redefinition, we keep the original class so this scratch class 586 // doesn't have an array class. Either way, assert that there is nothing 587 // to deallocate. 588 assert(array_klasses() == NULL, "array classes shouldn't be created for this class yet"); 589 590 // Release C heap allocated data that this points to, which includes 591 // reference counting symbol names. 592 release_C_heap_structures_internal(); 593 594 deallocate_methods(loader_data, methods()); 595 set_methods(NULL); 596 597 deallocate_record_components(loader_data, record_components()); 598 set_record_components(NULL); 599 600 if (method_ordering() != NULL && 601 method_ordering() != Universe::the_empty_int_array() && 602 !method_ordering()->is_shared()) { 603 MetadataFactory::free_array<int>(loader_data, method_ordering()); 604 } 605 set_method_ordering(NULL); 606 607 // default methods can be empty 608 if (default_methods() != NULL && 609 default_methods() != Universe::the_empty_method_array() && 610 !default_methods()->is_shared()) { 611 MetadataFactory::free_array<Method*>(loader_data, default_methods()); 612 } 613 // Do NOT deallocate the default methods, they are owned by superinterfaces. 614 set_default_methods(NULL); 615 616 // default methods vtable indices can be empty 617 if (default_vtable_indices() != NULL && 618 !default_vtable_indices()->is_shared()) { 619 MetadataFactory::free_array<int>(loader_data, default_vtable_indices()); 620 } 621 set_default_vtable_indices(NULL); 622 623 624 // This array is in Klass, but remove it with the InstanceKlass since 625 // this place would be the only caller and it can share memory with transitive 626 // interfaces. 627 if (secondary_supers() != NULL && 628 secondary_supers() != Universe::the_empty_klass_array() && 629 // see comments in compute_secondary_supers about the following cast 630 (address)(secondary_supers()) != (address)(transitive_interfaces()) && 631 !secondary_supers()->is_shared()) { 632 MetadataFactory::free_array<Klass*>(loader_data, secondary_supers()); 633 } 634 set_secondary_supers(NULL); 635 636 deallocate_interfaces(loader_data, super(), local_interfaces(), transitive_interfaces()); 637 set_transitive_interfaces(NULL); 638 set_local_interfaces(NULL); 639 640 if (fields() != NULL && !fields()->is_shared()) { 641 MetadataFactory::free_array<jushort>(loader_data, fields()); 642 } 643 set_fields(NULL, 0); 644 645 // If a method from a redefined class is using this constant pool, don't 646 // delete it, yet. The new class's previous version will point to this. 647 if (constants() != NULL) { 648 assert (!constants()->on_stack(), "shouldn't be called if anything is onstack"); 649 if (!constants()->is_shared()) { 650 MetadataFactory::free_metadata(loader_data, constants()); 651 } 652 // Delete any cached resolution errors for the constant pool 653 SystemDictionary::delete_resolution_error(constants()); 654 655 set_constants(NULL); 656 } 657 658 if (inner_classes() != NULL && 659 inner_classes() != Universe::the_empty_short_array() && 660 !inner_classes()->is_shared()) { 661 MetadataFactory::free_array<jushort>(loader_data, inner_classes()); 662 } 663 set_inner_classes(NULL); 664 665 if (nest_members() != NULL && 666 nest_members() != Universe::the_empty_short_array() && 667 !nest_members()->is_shared()) { 668 MetadataFactory::free_array<jushort>(loader_data, nest_members()); 669 } 670 set_nest_members(NULL); 671 672 // We should deallocate the Annotations instance if it's not in shared spaces. 673 if (annotations() != NULL && !annotations()->is_shared()) { 674 MetadataFactory::free_metadata(loader_data, annotations()); 675 } 676 set_annotations(NULL); 677 678 if (Arguments::is_dumping_archive()) { 679 SystemDictionaryShared::remove_dumptime_info(this); 680 } 681 } 682 683 bool InstanceKlass::should_be_initialized() const { 684 return !is_initialized(); 685 } 686 687 klassItable InstanceKlass::itable() const { 688 return klassItable(const_cast<InstanceKlass*>(this)); 689 } 690 691 void InstanceKlass::eager_initialize(Thread *thread) { 692 if (!EagerInitialization) return; 693 694 if (this->is_not_initialized()) { 695 // abort if the the class has a class initializer 696 if (this->class_initializer() != NULL) return; 697 698 // abort if it is java.lang.Object (initialization is handled in genesis) 699 Klass* super_klass = super(); 700 if (super_klass == NULL) return; 701 702 // abort if the super class should be initialized 703 if (!InstanceKlass::cast(super_klass)->is_initialized()) return; 704 705 // call body to expose the this pointer 706 eager_initialize_impl(); 707 } 708 } 709 710 // JVMTI spec thinks there are signers and protection domain in the 711 // instanceKlass. These accessors pretend these fields are there. 712 // The hprof specification also thinks these fields are in InstanceKlass. 713 oop InstanceKlass::protection_domain() const { 714 // return the protection_domain from the mirror 715 return java_lang_Class::protection_domain(java_mirror()); 716 } 717 718 // To remove these from requires an incompatible change and CCC request. 719 objArrayOop InstanceKlass::signers() const { 720 // return the signers from the mirror 721 return java_lang_Class::signers(java_mirror()); 722 } 723 724 oop InstanceKlass::init_lock() const { 725 // return the init lock from the mirror 726 oop lock = java_lang_Class::init_lock(java_mirror()); 727 // Prevent reordering with any access of initialization state 728 OrderAccess::loadload(); 729 assert((oop)lock != NULL || !is_not_initialized(), // initialized or in_error state 730 "only fully initialized state can have a null lock"); 731 return lock; 732 } 733 734 // Set the initialization lock to null so the object can be GC'ed. Any racing 735 // threads to get this lock will see a null lock and will not lock. 736 // That's okay because they all check for initialized state after getting 737 // the lock and return. 738 void InstanceKlass::fence_and_clear_init_lock() { 739 // make sure previous stores are all done, notably the init_state. 740 OrderAccess::storestore(); 741 java_lang_Class::set_init_lock(java_mirror(), NULL); 742 assert(!is_not_initialized(), "class must be initialized now"); 743 } 744 745 void InstanceKlass::eager_initialize_impl() { 746 EXCEPTION_MARK; 747 HandleMark hm(THREAD); 748 Handle h_init_lock(THREAD, init_lock()); 749 ObjectLocker ol(h_init_lock, THREAD, h_init_lock() != NULL); 750 751 // abort if someone beat us to the initialization 752 if (!is_not_initialized()) return; // note: not equivalent to is_initialized() 753 754 ClassState old_state = init_state(); 755 link_class_impl(THREAD); 756 if (HAS_PENDING_EXCEPTION) { 757 CLEAR_PENDING_EXCEPTION; 758 // Abort if linking the class throws an exception. 759 760 // Use a test to avoid redundantly resetting the state if there's 761 // no change. Set_init_state() asserts that state changes make 762 // progress, whereas here we might just be spinning in place. 763 if (old_state != _init_state) 764 set_init_state(old_state); 765 } else { 766 // linking successfull, mark class as initialized 767 set_init_state(fully_initialized); 768 fence_and_clear_init_lock(); 769 // trace 770 if (log_is_enabled(Info, class, init)) { 771 ResourceMark rm(THREAD); 772 log_info(class, init)("[Initialized %s without side effects]", external_name()); 773 } 774 } 775 } 776 777 778 // See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization 779 // process. The step comments refers to the procedure described in that section. 780 // Note: implementation moved to static method to expose the this pointer. 781 void InstanceKlass::initialize(TRAPS) { 782 if (this->should_be_initialized()) { 783 initialize_impl(CHECK); 784 // Note: at this point the class may be initialized 785 // OR it may be in the state of being initialized 786 // in case of recursive initialization! 787 } else { 788 assert(is_initialized(), "sanity check"); 789 } 790 } 791 792 793 bool InstanceKlass::verify_code(TRAPS) { 794 // 1) Verify the bytecodes 795 return Verifier::verify(this, should_verify_class(), THREAD); 796 } 797 798 void InstanceKlass::link_class(TRAPS) { 799 assert(is_loaded(), "must be loaded"); 800 if (!is_linked()) { 801 link_class_impl(CHECK); 802 } 803 } 804 805 // Called to verify that a class can link during initialization, without 806 // throwing a VerifyError. 807 bool InstanceKlass::link_class_or_fail(TRAPS) { 808 assert(is_loaded(), "must be loaded"); 809 if (!is_linked()) { 810 link_class_impl(CHECK_false); 811 } 812 return is_linked(); 813 } 814 815 bool InstanceKlass::link_class_impl(TRAPS) { 816 if (DumpSharedSpaces && SystemDictionaryShared::has_class_failed_verification(this)) { 817 // This is for CDS dumping phase only -- we use the in_error_state to indicate that 818 // the class has failed verification. Throwing the NoClassDefFoundError here is just 819 // a convenient way to stop repeat attempts to verify the same (bad) class. 820 // 821 // Note that the NoClassDefFoundError is not part of the JLS, and should not be thrown 822 // if we are executing Java code. This is not a problem for CDS dumping phase since 823 // it doesn't execute any Java code. 824 ResourceMark rm(THREAD); 825 Exceptions::fthrow(THREAD_AND_LOCATION, 826 vmSymbols::java_lang_NoClassDefFoundError(), 827 "Class %s, or one of its supertypes, failed class initialization", 828 external_name()); 829 return false; 830 } 831 // return if already verified 832 if (is_linked()) { 833 return true; 834 } 835 836 // Timing 837 // timer handles recursion 838 assert(THREAD->is_Java_thread(), "non-JavaThread in link_class_impl"); 839 JavaThread* jt = (JavaThread*)THREAD; 840 841 // link super class before linking this class 842 Klass* super_klass = super(); 843 if (super_klass != NULL) { 844 if (super_klass->is_interface()) { // check if super class is an interface 845 ResourceMark rm(THREAD); 846 Exceptions::fthrow( 847 THREAD_AND_LOCATION, 848 vmSymbols::java_lang_IncompatibleClassChangeError(), 849 "class %s has interface %s as super class", 850 external_name(), 851 super_klass->external_name() 852 ); 853 return false; 854 } 855 856 InstanceKlass* ik_super = InstanceKlass::cast(super_klass); 857 ik_super->link_class_impl(CHECK_false); 858 } 859 860 // link all interfaces implemented by this class before linking this class 861 Array<InstanceKlass*>* interfaces = local_interfaces(); 862 int num_interfaces = interfaces->length(); 863 for (int index = 0; index < num_interfaces; index++) { 864 InstanceKlass* interk = interfaces->at(index); 865 interk->link_class_impl(CHECK_false); 866 } 867 868 // in case the class is linked in the process of linking its superclasses 869 if (is_linked()) { 870 return true; 871 } 872 873 // trace only the link time for this klass that includes 874 // the verification time 875 PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(), 876 ClassLoader::perf_class_link_selftime(), 877 ClassLoader::perf_classes_linked(), 878 jt->get_thread_stat()->perf_recursion_counts_addr(), 879 jt->get_thread_stat()->perf_timers_addr(), 880 PerfClassTraceTime::CLASS_LINK); 881 882 // verification & rewriting 883 { 884 HandleMark hm(THREAD); 885 Handle h_init_lock(THREAD, init_lock()); 886 ObjectLocker ol(h_init_lock, THREAD, h_init_lock() != NULL); 887 // rewritten will have been set if loader constraint error found 888 // on an earlier link attempt 889 // don't verify or rewrite if already rewritten 890 // 891 892 if (!is_linked()) { 893 if (!is_rewritten()) { 894 { 895 bool verify_ok = verify_code(THREAD); 896 if (!verify_ok) { 897 return false; 898 } 899 } 900 901 // Just in case a side-effect of verify linked this class already 902 // (which can sometimes happen since the verifier loads classes 903 // using custom class loaders, which are free to initialize things) 904 if (is_linked()) { 905 return true; 906 } 907 908 // also sets rewritten 909 rewrite_class(CHECK_false); 910 } else if (is_shared()) { 911 SystemDictionaryShared::check_verification_constraints(this, CHECK_false); 912 } 913 914 // relocate jsrs and link methods after they are all rewritten 915 link_methods(CHECK_false); 916 917 // Initialize the vtable and interface table after 918 // methods have been rewritten since rewrite may 919 // fabricate new Method*s. 920 // also does loader constraint checking 921 // 922 // initialize_vtable and initialize_itable need to be rerun for 923 // a shared class if the class is not loaded by the NULL classloader. 924 ClassLoaderData * loader_data = class_loader_data(); 925 if (!(is_shared() && 926 loader_data->is_the_null_class_loader_data())) { 927 vtable().initialize_vtable(true, CHECK_false); 928 itable().initialize_itable(true, CHECK_false); 929 } 930 #ifdef ASSERT 931 else { 932 vtable().verify(tty, true); 933 // In case itable verification is ever added. 934 // itable().verify(tty, true); 935 } 936 #endif 937 set_init_state(linked); 938 if (JvmtiExport::should_post_class_prepare()) { 939 Thread *thread = THREAD; 940 assert(thread->is_Java_thread(), "thread->is_Java_thread()"); 941 JvmtiExport::post_class_prepare((JavaThread *) thread, this); 942 } 943 } 944 } 945 return true; 946 } 947 948 // Rewrite the byte codes of all of the methods of a class. 949 // The rewriter must be called exactly once. Rewriting must happen after 950 // verification but before the first method of the class is executed. 951 void InstanceKlass::rewrite_class(TRAPS) { 952 assert(is_loaded(), "must be loaded"); 953 if (is_rewritten()) { 954 assert(is_shared(), "rewriting an unshared class?"); 955 return; 956 } 957 Rewriter::rewrite(this, CHECK); 958 set_rewritten(); 959 } 960 961 // Now relocate and link method entry points after class is rewritten. 962 // This is outside is_rewritten flag. In case of an exception, it can be 963 // executed more than once. 964 void InstanceKlass::link_methods(TRAPS) { 965 int len = methods()->length(); 966 for (int i = len-1; i >= 0; i--) { 967 methodHandle m(THREAD, methods()->at(i)); 968 969 // Set up method entry points for compiler and interpreter . 970 m->link_method(m, CHECK); 971 } 972 } 973 974 // Eagerly initialize superinterfaces that declare default methods (concrete instance: any access) 975 void InstanceKlass::initialize_super_interfaces(TRAPS) { 976 assert (has_nonstatic_concrete_methods(), "caller should have checked this"); 977 for (int i = 0; i < local_interfaces()->length(); ++i) { 978 InstanceKlass* ik = local_interfaces()->at(i); 979 980 // Initialization is depth first search ie. we start with top of the inheritance tree 981 // has_nonstatic_concrete_methods drives searching superinterfaces since it 982 // means has_nonstatic_concrete_methods in its superinterface hierarchy 983 if (ik->has_nonstatic_concrete_methods()) { 984 ik->initialize_super_interfaces(CHECK); 985 } 986 987 // Only initialize() interfaces that "declare" concrete methods. 988 if (ik->should_be_initialized() && ik->declares_nonstatic_concrete_methods()) { 989 ik->initialize(CHECK); 990 } 991 } 992 } 993 994 void InstanceKlass::initialize_impl(TRAPS) { 995 HandleMark hm(THREAD); 996 997 // Make sure klass is linked (verified) before initialization 998 // A class could already be verified, since it has been reflected upon. 999 link_class(CHECK); 1000 1001 DTRACE_CLASSINIT_PROBE(required, -1); 1002 1003 bool wait = false; 1004 1005 assert(THREAD->is_Java_thread(), "non-JavaThread in initialize_impl"); 1006 JavaThread* jt = (JavaThread*)THREAD; 1007 1008 // refer to the JVM book page 47 for description of steps 1009 // Step 1 1010 { 1011 Handle h_init_lock(THREAD, init_lock()); 1012 ObjectLocker ol(h_init_lock, THREAD, h_init_lock() != NULL); 1013 1014 // Step 2 1015 // If we were to use wait() instead of waitInterruptibly() then 1016 // we might end up throwing IE from link/symbol resolution sites 1017 // that aren't expected to throw. This would wreak havoc. See 6320309. 1018 while (is_being_initialized() && !is_reentrant_initialization(jt)) { 1019 wait = true; 1020 jt->set_class_to_be_initialized(this); 1021 ol.wait_uninterruptibly(jt); 1022 jt->set_class_to_be_initialized(NULL); 1023 } 1024 1025 // Step 3 1026 if (is_being_initialized() && is_reentrant_initialization(jt)) { 1027 DTRACE_CLASSINIT_PROBE_WAIT(recursive, -1, wait); 1028 return; 1029 } 1030 1031 // Step 4 1032 if (is_initialized()) { 1033 DTRACE_CLASSINIT_PROBE_WAIT(concurrent, -1, wait); 1034 return; 1035 } 1036 1037 // Step 5 1038 if (is_in_error_state()) { 1039 DTRACE_CLASSINIT_PROBE_WAIT(erroneous, -1, wait); 1040 ResourceMark rm(THREAD); 1041 const char* desc = "Could not initialize class "; 1042 const char* className = external_name(); 1043 size_t msglen = strlen(desc) + strlen(className) + 1; 1044 char* message = NEW_RESOURCE_ARRAY(char, msglen); 1045 if (NULL == message) { 1046 // Out of memory: can't create detailed error message 1047 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), className); 1048 } else { 1049 jio_snprintf(message, msglen, "%s%s", desc, className); 1050 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), message); 1051 } 1052 } 1053 1054 // Step 6 1055 set_init_state(being_initialized); 1056 set_init_thread(jt); 1057 } 1058 1059 // Step 7 1060 // Next, if C is a class rather than an interface, initialize it's super class and super 1061 // interfaces. 1062 if (!is_interface()) { 1063 Klass* super_klass = super(); 1064 if (super_klass != NULL && super_klass->should_be_initialized()) { 1065 super_klass->initialize(THREAD); 1066 } 1067 // If C implements any interface that declares a non-static, concrete method, 1068 // the initialization of C triggers initialization of its super interfaces. 1069 // Only need to recurse if has_nonstatic_concrete_methods which includes declaring and 1070 // having a superinterface that declares, non-static, concrete methods 1071 if (!HAS_PENDING_EXCEPTION && has_nonstatic_concrete_methods()) { 1072 initialize_super_interfaces(THREAD); 1073 } 1074 1075 // If any exceptions, complete abruptly, throwing the same exception as above. 1076 if (HAS_PENDING_EXCEPTION) { 1077 Handle e(THREAD, PENDING_EXCEPTION); 1078 CLEAR_PENDING_EXCEPTION; 1079 { 1080 EXCEPTION_MARK; 1081 // Locks object, set state, and notify all waiting threads 1082 set_initialization_state_and_notify(initialization_error, THREAD); 1083 CLEAR_PENDING_EXCEPTION; 1084 } 1085 DTRACE_CLASSINIT_PROBE_WAIT(super__failed, -1, wait); 1086 THROW_OOP(e()); 1087 } 1088 } 1089 1090 1091 // Look for aot compiled methods for this klass, including class initializer. 1092 AOTLoader::load_for_klass(this, THREAD); 1093 1094 // Step 8 1095 { 1096 DTRACE_CLASSINIT_PROBE_WAIT(clinit, -1, wait); 1097 // Timer includes any side effects of class initialization (resolution, 1098 // etc), but not recursive entry into call_class_initializer(). 1099 PerfClassTraceTime timer(ClassLoader::perf_class_init_time(), 1100 ClassLoader::perf_class_init_selftime(), 1101 ClassLoader::perf_classes_inited(), 1102 jt->get_thread_stat()->perf_recursion_counts_addr(), 1103 jt->get_thread_stat()->perf_timers_addr(), 1104 PerfClassTraceTime::CLASS_CLINIT); 1105 call_class_initializer(THREAD); 1106 } 1107 1108 // Step 9 1109 if (!HAS_PENDING_EXCEPTION) { 1110 set_initialization_state_and_notify(fully_initialized, CHECK); 1111 { 1112 debug_only(vtable().verify(tty, true);) 1113 } 1114 } 1115 else { 1116 // Step 10 and 11 1117 Handle e(THREAD, PENDING_EXCEPTION); 1118 CLEAR_PENDING_EXCEPTION; 1119 // JVMTI has already reported the pending exception 1120 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError 1121 JvmtiExport::clear_detected_exception(jt); 1122 { 1123 EXCEPTION_MARK; 1124 set_initialization_state_and_notify(initialization_error, THREAD); 1125 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, class initialization error is thrown below 1126 // JVMTI has already reported the pending exception 1127 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError 1128 JvmtiExport::clear_detected_exception(jt); 1129 } 1130 DTRACE_CLASSINIT_PROBE_WAIT(error, -1, wait); 1131 if (e->is_a(SystemDictionary::Error_klass())) { 1132 THROW_OOP(e()); 1133 } else { 1134 JavaCallArguments args(e); 1135 THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(), 1136 vmSymbols::throwable_void_signature(), 1137 &args); 1138 } 1139 } 1140 DTRACE_CLASSINIT_PROBE_WAIT(end, -1, wait); 1141 } 1142 1143 1144 void InstanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) { 1145 Handle h_init_lock(THREAD, init_lock()); 1146 if (h_init_lock() != NULL) { 1147 ObjectLocker ol(h_init_lock, THREAD); 1148 set_init_thread(NULL); // reset _init_thread before changing _init_state 1149 set_init_state(state); 1150 fence_and_clear_init_lock(); 1151 ol.notify_all(CHECK); 1152 } else { 1153 assert(h_init_lock() != NULL, "The initialization state should never be set twice"); 1154 set_init_thread(NULL); // reset _init_thread before changing _init_state 1155 set_init_state(state); 1156 } 1157 } 1158 1159 Klass* InstanceKlass::implementor() const { 1160 Klass* volatile* k = adr_implementor(); 1161 if (k == NULL) { 1162 return NULL; 1163 } else { 1164 // This load races with inserts, and therefore needs acquire. 1165 Klass* kls = Atomic::load_acquire(k); 1166 if (kls != NULL && !kls->is_loader_alive()) { 1167 return NULL; // don't return unloaded class 1168 } else { 1169 return kls; 1170 } 1171 } 1172 } 1173 1174 1175 void InstanceKlass::set_implementor(Klass* k) { 1176 assert_locked_or_safepoint(Compile_lock); 1177 assert(is_interface(), "not interface"); 1178 Klass* volatile* addr = adr_implementor(); 1179 assert(addr != NULL, "null addr"); 1180 if (addr != NULL) { 1181 Atomic::release_store(addr, k); 1182 } 1183 } 1184 1185 int InstanceKlass::nof_implementors() const { 1186 Klass* k = implementor(); 1187 if (k == NULL) { 1188 return 0; 1189 } else if (k != this) { 1190 return 1; 1191 } else { 1192 return 2; 1193 } 1194 } 1195 1196 // The embedded _implementor field can only record one implementor. 1197 // When there are more than one implementors, the _implementor field 1198 // is set to the interface Klass* itself. Following are the possible 1199 // values for the _implementor field: 1200 // NULL - no implementor 1201 // implementor Klass* - one implementor 1202 // self - more than one implementor 1203 // 1204 // The _implementor field only exists for interfaces. 1205 void InstanceKlass::add_implementor(Klass* k) { 1206 if (Universe::is_fully_initialized()) { 1207 assert_lock_strong(Compile_lock); 1208 } 1209 assert(is_interface(), "not interface"); 1210 // Filter out my subinterfaces. 1211 // (Note: Interfaces are never on the subklass list.) 1212 if (InstanceKlass::cast(k)->is_interface()) return; 1213 1214 // Filter out subclasses whose supers already implement me. 1215 // (Note: CHA must walk subclasses of direct implementors 1216 // in order to locate indirect implementors.) 1217 Klass* sk = k->super(); 1218 if (sk != NULL && InstanceKlass::cast(sk)->implements_interface(this)) 1219 // We only need to check one immediate superclass, since the 1220 // implements_interface query looks at transitive_interfaces. 1221 // Any supers of the super have the same (or fewer) transitive_interfaces. 1222 return; 1223 1224 Klass* ik = implementor(); 1225 if (ik == NULL) { 1226 set_implementor(k); 1227 } else if (ik != this && ik != k) { 1228 // There is already an implementor. Use itself as an indicator of 1229 // more than one implementors. 1230 set_implementor(this); 1231 } 1232 1233 // The implementor also implements the transitive_interfaces 1234 for (int index = 0; index < local_interfaces()->length(); index++) { 1235 InstanceKlass::cast(local_interfaces()->at(index))->add_implementor(k); 1236 } 1237 } 1238 1239 void InstanceKlass::init_implementor() { 1240 if (is_interface()) { 1241 set_implementor(NULL); 1242 } 1243 } 1244 1245 1246 void InstanceKlass::process_interfaces(Thread *thread) { 1247 // link this class into the implementors list of every interface it implements 1248 for (int i = local_interfaces()->length() - 1; i >= 0; i--) { 1249 assert(local_interfaces()->at(i)->is_klass(), "must be a klass"); 1250 InstanceKlass* interf = InstanceKlass::cast(local_interfaces()->at(i)); 1251 assert(interf->is_interface(), "expected interface"); 1252 interf->add_implementor(this); 1253 } 1254 } 1255 1256 bool InstanceKlass::can_be_primary_super_slow() const { 1257 if (is_interface()) 1258 return false; 1259 else 1260 return Klass::can_be_primary_super_slow(); 1261 } 1262 1263 GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots, 1264 Array<InstanceKlass*>* transitive_interfaces) { 1265 // The secondaries are the implemented interfaces. 1266 Array<InstanceKlass*>* interfaces = transitive_interfaces; 1267 int num_secondaries = num_extra_slots + interfaces->length(); 1268 if (num_secondaries == 0) { 1269 // Must share this for correct bootstrapping! 1270 set_secondary_supers(Universe::the_empty_klass_array()); 1271 return NULL; 1272 } else if (num_extra_slots == 0) { 1273 // The secondary super list is exactly the same as the transitive interfaces, so 1274 // let's use it instead of making a copy. 1275 // Redefine classes has to be careful not to delete this! 1276 // We need the cast because Array<Klass*> is NOT a supertype of Array<InstanceKlass*>, 1277 // (but it's safe to do here because we won't write into _secondary_supers from this point on). 1278 set_secondary_supers((Array<Klass*>*)(address)interfaces); 1279 return NULL; 1280 } else { 1281 // Copy transitive interfaces to a temporary growable array to be constructed 1282 // into the secondary super list with extra slots. 1283 GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length()); 1284 for (int i = 0; i < interfaces->length(); i++) { 1285 secondaries->push(interfaces->at(i)); 1286 } 1287 return secondaries; 1288 } 1289 } 1290 1291 bool InstanceKlass::implements_interface(Klass* k) const { 1292 if (this == k) return true; 1293 assert(k->is_interface(), "should be an interface class"); 1294 for (int i = 0; i < transitive_interfaces()->length(); i++) { 1295 if (transitive_interfaces()->at(i) == k) { 1296 return true; 1297 } 1298 } 1299 return false; 1300 } 1301 1302 bool InstanceKlass::is_same_or_direct_interface(Klass *k) const { 1303 // Verify direct super interface 1304 if (this == k) return true; 1305 assert(k->is_interface(), "should be an interface class"); 1306 for (int i = 0; i < local_interfaces()->length(); i++) { 1307 if (local_interfaces()->at(i) == k) { 1308 return true; 1309 } 1310 } 1311 return false; 1312 } 1313 1314 objArrayOop InstanceKlass::allocate_objArray(int n, int length, TRAPS) { 1315 check_array_allocation_length(length, arrayOopDesc::max_array_length(T_OBJECT), CHECK_NULL); 1316 int size = objArrayOopDesc::object_size(length); 1317 Klass* ak = array_klass(n, CHECK_NULL); 1318 objArrayOop o = (objArrayOop)Universe::heap()->array_allocate(ak, size, length, 1319 /* do_zero */ true, CHECK_NULL); 1320 return o; 1321 } 1322 1323 instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) { 1324 if (TraceFinalizerRegistration) { 1325 tty->print("Registered "); 1326 i->print_value_on(tty); 1327 tty->print_cr(" (" INTPTR_FORMAT ") as finalizable", p2i(i)); 1328 } 1329 instanceHandle h_i(THREAD, i); 1330 // Pass the handle as argument, JavaCalls::call expects oop as jobjects 1331 JavaValue result(T_VOID); 1332 JavaCallArguments args(h_i); 1333 methodHandle mh (THREAD, Universe::finalizer_register_method()); 1334 JavaCalls::call(&result, mh, &args, CHECK_NULL); 1335 return h_i(); 1336 } 1337 1338 instanceOop InstanceKlass::allocate_instance(TRAPS) { 1339 bool has_finalizer_flag = has_finalizer(); // Query before possible GC 1340 int size = size_helper(); // Query before forming handle. 1341 1342 instanceOop i; 1343 1344 i = (instanceOop)Universe::heap()->obj_allocate(this, size, CHECK_NULL); 1345 if (has_finalizer_flag && !RegisterFinalizersAtInit) { 1346 i = register_finalizer(i, CHECK_NULL); 1347 } 1348 return i; 1349 } 1350 1351 instanceHandle InstanceKlass::allocate_instance_handle(TRAPS) { 1352 return instanceHandle(THREAD, allocate_instance(THREAD)); 1353 } 1354 1355 void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) { 1356 if (is_interface() || is_abstract()) { 1357 ResourceMark rm(THREAD); 1358 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError() 1359 : vmSymbols::java_lang_InstantiationException(), external_name()); 1360 } 1361 if (this == SystemDictionary::Class_klass()) { 1362 ResourceMark rm(THREAD); 1363 THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError() 1364 : vmSymbols::java_lang_IllegalAccessException(), external_name()); 1365 } 1366 } 1367 1368 Klass* InstanceKlass::array_klass_impl(bool or_null, int n, TRAPS) { 1369 // Need load-acquire for lock-free read 1370 if (array_klasses_acquire() == NULL) { 1371 if (or_null) return NULL; 1372 1373 ResourceMark rm(THREAD); 1374 JavaThread *jt = (JavaThread *)THREAD; 1375 { 1376 // Atomic creation of array_klasses 1377 MutexLocker ma(THREAD, MultiArray_lock); 1378 1379 // Check if update has already taken place 1380 if (array_klasses() == NULL) { 1381 Klass* k = ObjArrayKlass::allocate_objArray_klass(class_loader_data(), 1, this, CHECK_NULL); 1382 // use 'release' to pair with lock-free load 1383 release_set_array_klasses(k); 1384 } 1385 } 1386 } 1387 // _this will always be set at this point 1388 ObjArrayKlass* oak = (ObjArrayKlass*)array_klasses(); 1389 if (or_null) { 1390 return oak->array_klass_or_null(n); 1391 } 1392 return oak->array_klass(n, THREAD); 1393 } 1394 1395 Klass* InstanceKlass::array_klass_impl(bool or_null, TRAPS) { 1396 return array_klass_impl(or_null, 1, THREAD); 1397 } 1398 1399 static int call_class_initializer_counter = 0; // for debugging 1400 1401 Method* InstanceKlass::class_initializer() const { 1402 Method* clinit = find_method( 1403 vmSymbols::class_initializer_name(), vmSymbols::void_method_signature()); 1404 if (clinit != NULL && clinit->has_valid_initializer_flags()) { 1405 return clinit; 1406 } 1407 return NULL; 1408 } 1409 1410 void InstanceKlass::call_class_initializer(TRAPS) { 1411 if (ReplayCompiles && 1412 (ReplaySuppressInitializers == 1 || 1413 (ReplaySuppressInitializers >= 2 && class_loader() != NULL))) { 1414 // Hide the existence of the initializer for the purpose of replaying the compile 1415 return; 1416 } 1417 1418 methodHandle h_method(THREAD, class_initializer()); 1419 assert(!is_initialized(), "we cannot initialize twice"); 1420 LogTarget(Info, class, init) lt; 1421 if (lt.is_enabled()) { 1422 ResourceMark rm(THREAD); 1423 LogStream ls(lt); 1424 ls.print("%d Initializing ", call_class_initializer_counter++); 1425 name()->print_value_on(&ls); 1426 ls.print_cr("%s (" INTPTR_FORMAT ")", h_method() == NULL ? "(no method)" : "", p2i(this)); 1427 } 1428 if (h_method() != NULL) { 1429 JavaCallArguments args; // No arguments 1430 JavaValue result(T_VOID); 1431 JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args) 1432 } 1433 } 1434 1435 1436 void InstanceKlass::mask_for(const methodHandle& method, int bci, 1437 InterpreterOopMap* entry_for) { 1438 // Lazily create the _oop_map_cache at first request 1439 // Lock-free access requires load_acquire. 1440 OopMapCache* oop_map_cache = Atomic::load_acquire(&_oop_map_cache); 1441 if (oop_map_cache == NULL) { 1442 MutexLocker x(OopMapCacheAlloc_lock); 1443 // Check if _oop_map_cache was allocated while we were waiting for this lock 1444 if ((oop_map_cache = _oop_map_cache) == NULL) { 1445 oop_map_cache = new OopMapCache(); 1446 // Ensure _oop_map_cache is stable, since it is examined without a lock 1447 Atomic::release_store(&_oop_map_cache, oop_map_cache); 1448 } 1449 } 1450 // _oop_map_cache is constant after init; lookup below does its own locking. 1451 oop_map_cache->lookup(method, bci, entry_for); 1452 } 1453 1454 bool InstanceKlass::contains_field_offset(int offset) { 1455 fieldDescriptor fd; 1456 return find_field_from_offset(offset, false, &fd); 1457 } 1458 1459 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const { 1460 for (JavaFieldStream fs(this); !fs.done(); fs.next()) { 1461 Symbol* f_name = fs.name(); 1462 Symbol* f_sig = fs.signature(); 1463 if (f_name == name && f_sig == sig) { 1464 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index()); 1465 return true; 1466 } 1467 } 1468 return false; 1469 } 1470 1471 1472 Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const { 1473 const int n = local_interfaces()->length(); 1474 for (int i = 0; i < n; i++) { 1475 Klass* intf1 = local_interfaces()->at(i); 1476 assert(intf1->is_interface(), "just checking type"); 1477 // search for field in current interface 1478 if (InstanceKlass::cast(intf1)->find_local_field(name, sig, fd)) { 1479 assert(fd->is_static(), "interface field must be static"); 1480 return intf1; 1481 } 1482 // search for field in direct superinterfaces 1483 Klass* intf2 = InstanceKlass::cast(intf1)->find_interface_field(name, sig, fd); 1484 if (intf2 != NULL) return intf2; 1485 } 1486 // otherwise field lookup fails 1487 return NULL; 1488 } 1489 1490 1491 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const { 1492 // search order according to newest JVM spec (5.4.3.2, p.167). 1493 // 1) search for field in current klass 1494 if (find_local_field(name, sig, fd)) { 1495 return const_cast<InstanceKlass*>(this); 1496 } 1497 // 2) search for field recursively in direct superinterfaces 1498 { Klass* intf = find_interface_field(name, sig, fd); 1499 if (intf != NULL) return intf; 1500 } 1501 // 3) apply field lookup recursively if superclass exists 1502 { Klass* supr = super(); 1503 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, fd); 1504 } 1505 // 4) otherwise field lookup fails 1506 return NULL; 1507 } 1508 1509 1510 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const { 1511 // search order according to newest JVM spec (5.4.3.2, p.167). 1512 // 1) search for field in current klass 1513 if (find_local_field(name, sig, fd)) { 1514 if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this); 1515 } 1516 // 2) search for field recursively in direct superinterfaces 1517 if (is_static) { 1518 Klass* intf = find_interface_field(name, sig, fd); 1519 if (intf != NULL) return intf; 1520 } 1521 // 3) apply field lookup recursively if superclass exists 1522 { Klass* supr = super(); 1523 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, is_static, fd); 1524 } 1525 // 4) otherwise field lookup fails 1526 return NULL; 1527 } 1528 1529 1530 bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const { 1531 for (JavaFieldStream fs(this); !fs.done(); fs.next()) { 1532 if (fs.offset() == offset) { 1533 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index()); 1534 if (fd->is_static() == is_static) return true; 1535 } 1536 } 1537 return false; 1538 } 1539 1540 1541 bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const { 1542 Klass* klass = const_cast<InstanceKlass*>(this); 1543 while (klass != NULL) { 1544 if (InstanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) { 1545 return true; 1546 } 1547 klass = klass->super(); 1548 } 1549 return false; 1550 } 1551 1552 1553 void InstanceKlass::methods_do(void f(Method* method)) { 1554 // Methods aren't stable until they are loaded. This can be read outside 1555 // a lock through the ClassLoaderData for profiling 1556 if (!is_loaded()) { 1557 return; 1558 } 1559 1560 int len = methods()->length(); 1561 for (int index = 0; index < len; index++) { 1562 Method* m = methods()->at(index); 1563 assert(m->is_method(), "must be method"); 1564 f(m); 1565 } 1566 } 1567 1568 1569 void InstanceKlass::do_local_static_fields(FieldClosure* cl) { 1570 for (JavaFieldStream fs(this); !fs.done(); fs.next()) { 1571 if (fs.access_flags().is_static()) { 1572 fieldDescriptor& fd = fs.field_descriptor(); 1573 cl->do_field(&fd); 1574 } 1575 } 1576 } 1577 1578 1579 void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle mirror, TRAPS) { 1580 for (JavaFieldStream fs(this); !fs.done(); fs.next()) { 1581 if (fs.access_flags().is_static()) { 1582 fieldDescriptor& fd = fs.field_descriptor(); 1583 f(&fd, mirror, CHECK); 1584 } 1585 } 1586 } 1587 1588 1589 static int compare_fields_by_offset(int* a, int* b) { 1590 return a[0] - b[0]; 1591 } 1592 1593 void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) { 1594 InstanceKlass* super = superklass(); 1595 if (super != NULL) { 1596 super->do_nonstatic_fields(cl); 1597 } 1598 fieldDescriptor fd; 1599 int length = java_fields_count(); 1600 // In DebugInfo nonstatic fields are sorted by offset. 1601 int* fields_sorted = NEW_C_HEAP_ARRAY(int, 2*(length+1), mtClass); 1602 int j = 0; 1603 for (int i = 0; i < length; i += 1) { 1604 fd.reinitialize(this, i); 1605 if (!fd.is_static()) { 1606 fields_sorted[j + 0] = fd.offset(); 1607 fields_sorted[j + 1] = i; 1608 j += 2; 1609 } 1610 } 1611 if (j > 0) { 1612 length = j; 1613 // _sort_Fn is defined in growableArray.hpp. 1614 qsort(fields_sorted, length/2, 2*sizeof(int), (_sort_Fn)compare_fields_by_offset); 1615 for (int i = 0; i < length; i += 2) { 1616 fd.reinitialize(this, fields_sorted[i + 1]); 1617 assert(!fd.is_static() && fd.offset() == fields_sorted[i], "only nonstatic fields"); 1618 cl->do_field(&fd); 1619 } 1620 } 1621 FREE_C_HEAP_ARRAY(int, fields_sorted); 1622 } 1623 1624 1625 void InstanceKlass::array_klasses_do(void f(Klass* k, TRAPS), TRAPS) { 1626 if (array_klasses() != NULL) 1627 ArrayKlass::cast(array_klasses())->array_klasses_do(f, THREAD); 1628 } 1629 1630 void InstanceKlass::array_klasses_do(void f(Klass* k)) { 1631 if (array_klasses() != NULL) 1632 ArrayKlass::cast(array_klasses())->array_klasses_do(f); 1633 } 1634 1635 #ifdef ASSERT 1636 static int linear_search(const Array<Method*>* methods, 1637 const Symbol* name, 1638 const Symbol* signature) { 1639 const int len = methods->length(); 1640 for (int index = 0; index < len; index++) { 1641 const Method* const m = methods->at(index); 1642 assert(m->is_method(), "must be method"); 1643 if (m->signature() == signature && m->name() == name) { 1644 return index; 1645 } 1646 } 1647 return -1; 1648 } 1649 #endif 1650 1651 bool InstanceKlass::_disable_method_binary_search = false; 1652 1653 NOINLINE int linear_search(const Array<Method*>* methods, const Symbol* name) { 1654 int len = methods->length(); 1655 int l = 0; 1656 int h = len - 1; 1657 while (l <= h) { 1658 Method* m = methods->at(l); 1659 if (m->name() == name) { 1660 return l; 1661 } 1662 l++; 1663 } 1664 return -1; 1665 } 1666 1667 inline int InstanceKlass::quick_search(const Array<Method*>* methods, const Symbol* name) { 1668 if (_disable_method_binary_search) { 1669 assert(DynamicDumpSharedSpaces, "must be"); 1670 // At the final stage of dynamic dumping, the methods array may not be sorted 1671 // by ascending addresses of their names, so we can't use binary search anymore. 1672 // However, methods with the same name are still laid out consecutively inside the 1673 // methods array, so let's look for the first one that matches. 1674 return linear_search(methods, name); 1675 } 1676 1677 int len = methods->length(); 1678 int l = 0; 1679 int h = len - 1; 1680 1681 // methods are sorted by ascending addresses of their names, so do binary search 1682 while (l <= h) { 1683 int mid = (l + h) >> 1; 1684 Method* m = methods->at(mid); 1685 assert(m->is_method(), "must be method"); 1686 int res = m->name()->fast_compare(name); 1687 if (res == 0) { 1688 return mid; 1689 } else if (res < 0) { 1690 l = mid + 1; 1691 } else { 1692 h = mid - 1; 1693 } 1694 } 1695 return -1; 1696 } 1697 1698 // find_method looks up the name/signature in the local methods array 1699 Method* InstanceKlass::find_method(const Symbol* name, 1700 const Symbol* signature) const { 1701 return find_method_impl(name, signature, find_overpass, find_static, find_private); 1702 } 1703 1704 Method* InstanceKlass::find_method_impl(const Symbol* name, 1705 const Symbol* signature, 1706 OverpassLookupMode overpass_mode, 1707 StaticLookupMode static_mode, 1708 PrivateLookupMode private_mode) const { 1709 return InstanceKlass::find_method_impl(methods(), 1710 name, 1711 signature, 1712 overpass_mode, 1713 static_mode, 1714 private_mode); 1715 } 1716 1717 // find_instance_method looks up the name/signature in the local methods array 1718 // and skips over static methods 1719 Method* InstanceKlass::find_instance_method(const Array<Method*>* methods, 1720 const Symbol* name, 1721 const Symbol* signature, 1722 PrivateLookupMode private_mode) { 1723 Method* const meth = InstanceKlass::find_method_impl(methods, 1724 name, 1725 signature, 1726 find_overpass, 1727 skip_static, 1728 private_mode); 1729 assert(((meth == NULL) || !meth->is_static()), 1730 "find_instance_method should have skipped statics"); 1731 return meth; 1732 } 1733 1734 // find_instance_method looks up the name/signature in the local methods array 1735 // and skips over static methods 1736 Method* InstanceKlass::find_instance_method(const Symbol* name, 1737 const Symbol* signature, 1738 PrivateLookupMode private_mode) const { 1739 return InstanceKlass::find_instance_method(methods(), name, signature, private_mode); 1740 } 1741 1742 // Find looks up the name/signature in the local methods array 1743 // and filters on the overpass, static and private flags 1744 // This returns the first one found 1745 // note that the local methods array can have up to one overpass, one static 1746 // and one instance (private or not) with the same name/signature 1747 Method* InstanceKlass::find_local_method(const Symbol* name, 1748 const Symbol* signature, 1749 OverpassLookupMode overpass_mode, 1750 StaticLookupMode static_mode, 1751 PrivateLookupMode private_mode) const { 1752 return InstanceKlass::find_method_impl(methods(), 1753 name, 1754 signature, 1755 overpass_mode, 1756 static_mode, 1757 private_mode); 1758 } 1759 1760 // Find looks up the name/signature in the local methods array 1761 // and filters on the overpass, static and private flags 1762 // This returns the first one found 1763 // note that the local methods array can have up to one overpass, one static 1764 // and one instance (private or not) with the same name/signature 1765 Method* InstanceKlass::find_local_method(const Array<Method*>* methods, 1766 const Symbol* name, 1767 const Symbol* signature, 1768 OverpassLookupMode overpass_mode, 1769 StaticLookupMode static_mode, 1770 PrivateLookupMode private_mode) { 1771 return InstanceKlass::find_method_impl(methods, 1772 name, 1773 signature, 1774 overpass_mode, 1775 static_mode, 1776 private_mode); 1777 } 1778 1779 Method* InstanceKlass::find_method(const Array<Method*>* methods, 1780 const Symbol* name, 1781 const Symbol* signature) { 1782 return InstanceKlass::find_method_impl(methods, 1783 name, 1784 signature, 1785 find_overpass, 1786 find_static, 1787 find_private); 1788 } 1789 1790 Method* InstanceKlass::find_method_impl(const Array<Method*>* methods, 1791 const Symbol* name, 1792 const Symbol* signature, 1793 OverpassLookupMode overpass_mode, 1794 StaticLookupMode static_mode, 1795 PrivateLookupMode private_mode) { 1796 int hit = find_method_index(methods, name, signature, overpass_mode, static_mode, private_mode); 1797 return hit >= 0 ? methods->at(hit): NULL; 1798 } 1799 1800 // true if method matches signature and conforms to skipping_X conditions. 1801 static bool method_matches(const Method* m, 1802 const Symbol* signature, 1803 bool skipping_overpass, 1804 bool skipping_static, 1805 bool skipping_private) { 1806 return ((m->signature() == signature) && 1807 (!skipping_overpass || !m->is_overpass()) && 1808 (!skipping_static || !m->is_static()) && 1809 (!skipping_private || !m->is_private())); 1810 } 1811 1812 // Used directly for default_methods to find the index into the 1813 // default_vtable_indices, and indirectly by find_method 1814 // find_method_index looks in the local methods array to return the index 1815 // of the matching name/signature. If, overpass methods are being ignored, 1816 // the search continues to find a potential non-overpass match. This capability 1817 // is important during method resolution to prefer a static method, for example, 1818 // over an overpass method. 1819 // There is the possibility in any _method's array to have the same name/signature 1820 // for a static method, an overpass method and a local instance method 1821 // To correctly catch a given method, the search criteria may need 1822 // to explicitly skip the other two. For local instance methods, it 1823 // is often necessary to skip private methods 1824 int InstanceKlass::find_method_index(const Array<Method*>* methods, 1825 const Symbol* name, 1826 const Symbol* signature, 1827 OverpassLookupMode overpass_mode, 1828 StaticLookupMode static_mode, 1829 PrivateLookupMode private_mode) { 1830 const bool skipping_overpass = (overpass_mode == skip_overpass); 1831 const bool skipping_static = (static_mode == skip_static); 1832 const bool skipping_private = (private_mode == skip_private); 1833 const int hit = quick_search(methods, name); 1834 if (hit != -1) { 1835 const Method* const m = methods->at(hit); 1836 1837 // Do linear search to find matching signature. First, quick check 1838 // for common case, ignoring overpasses if requested. 1839 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) { 1840 return hit; 1841 } 1842 1843 // search downwards through overloaded methods 1844 int i; 1845 for (i = hit - 1; i >= 0; --i) { 1846 const Method* const m = methods->at(i); 1847 assert(m->is_method(), "must be method"); 1848 if (m->name() != name) { 1849 break; 1850 } 1851 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) { 1852 return i; 1853 } 1854 } 1855 // search upwards 1856 for (i = hit + 1; i < methods->length(); ++i) { 1857 const Method* const m = methods->at(i); 1858 assert(m->is_method(), "must be method"); 1859 if (m->name() != name) { 1860 break; 1861 } 1862 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) { 1863 return i; 1864 } 1865 } 1866 // not found 1867 #ifdef ASSERT 1868 const int index = (skipping_overpass || skipping_static || skipping_private) ? -1 : 1869 linear_search(methods, name, signature); 1870 assert(-1 == index, "binary search should have found entry %d", index); 1871 #endif 1872 } 1873 return -1; 1874 } 1875 1876 int InstanceKlass::find_method_by_name(const Symbol* name, int* end) const { 1877 return find_method_by_name(methods(), name, end); 1878 } 1879 1880 int InstanceKlass::find_method_by_name(const Array<Method*>* methods, 1881 const Symbol* name, 1882 int* end_ptr) { 1883 assert(end_ptr != NULL, "just checking"); 1884 int start = quick_search(methods, name); 1885 int end = start + 1; 1886 if (start != -1) { 1887 while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start; 1888 while (end < methods->length() && (methods->at(end))->name() == name) ++end; 1889 *end_ptr = end; 1890 return start; 1891 } 1892 return -1; 1893 } 1894 1895 // uncached_lookup_method searches both the local class methods array and all 1896 // superclasses methods arrays, skipping any overpass methods in superclasses, 1897 // and possibly skipping private methods. 1898 Method* InstanceKlass::uncached_lookup_method(const Symbol* name, 1899 const Symbol* signature, 1900 OverpassLookupMode overpass_mode, 1901 PrivateLookupMode private_mode) const { 1902 OverpassLookupMode overpass_local_mode = overpass_mode; 1903 const Klass* klass = this; 1904 while (klass != NULL) { 1905 Method* const method = InstanceKlass::cast(klass)->find_method_impl(name, 1906 signature, 1907 overpass_local_mode, 1908 find_static, 1909 private_mode); 1910 if (method != NULL) { 1911 return method; 1912 } 1913 klass = klass->super(); 1914 overpass_local_mode = skip_overpass; // Always ignore overpass methods in superclasses 1915 } 1916 return NULL; 1917 } 1918 1919 #ifdef ASSERT 1920 // search through class hierarchy and return true if this class or 1921 // one of the superclasses was redefined 1922 bool InstanceKlass::has_redefined_this_or_super() const { 1923 const Klass* klass = this; 1924 while (klass != NULL) { 1925 if (InstanceKlass::cast(klass)->has_been_redefined()) { 1926 return true; 1927 } 1928 klass = klass->super(); 1929 } 1930 return false; 1931 } 1932 #endif 1933 1934 // lookup a method in the default methods list then in all transitive interfaces 1935 // Do NOT return private or static methods 1936 Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name, 1937 Symbol* signature) const { 1938 Method* m = NULL; 1939 if (default_methods() != NULL) { 1940 m = find_method(default_methods(), name, signature); 1941 } 1942 // Look up interfaces 1943 if (m == NULL) { 1944 m = lookup_method_in_all_interfaces(name, signature, find_defaults); 1945 } 1946 return m; 1947 } 1948 1949 // lookup a method in all the interfaces that this class implements 1950 // Do NOT return private or static methods, new in JDK8 which are not externally visible 1951 // They should only be found in the initial InterfaceMethodRef 1952 Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name, 1953 Symbol* signature, 1954 DefaultsLookupMode defaults_mode) const { 1955 Array<InstanceKlass*>* all_ifs = transitive_interfaces(); 1956 int num_ifs = all_ifs->length(); 1957 InstanceKlass *ik = NULL; 1958 for (int i = 0; i < num_ifs; i++) { 1959 ik = all_ifs->at(i); 1960 Method* m = ik->lookup_method(name, signature); 1961 if (m != NULL && m->is_public() && !m->is_static() && 1962 ((defaults_mode != skip_defaults) || !m->is_default_method())) { 1963 return m; 1964 } 1965 } 1966 return NULL; 1967 } 1968 1969 /* jni_id_for_impl for jfieldIds only */ 1970 JNIid* InstanceKlass::jni_id_for_impl(int offset) { 1971 MutexLocker ml(JfieldIdCreation_lock); 1972 // Retry lookup after we got the lock 1973 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset); 1974 if (probe == NULL) { 1975 // Slow case, allocate new static field identifier 1976 probe = new JNIid(this, offset, jni_ids()); 1977 set_jni_ids(probe); 1978 } 1979 return probe; 1980 } 1981 1982 1983 /* jni_id_for for jfieldIds only */ 1984 JNIid* InstanceKlass::jni_id_for(int offset) { 1985 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset); 1986 if (probe == NULL) { 1987 probe = jni_id_for_impl(offset); 1988 } 1989 return probe; 1990 } 1991 1992 u2 InstanceKlass::enclosing_method_data(int offset) const { 1993 const Array<jushort>* const inner_class_list = inner_classes(); 1994 if (inner_class_list == NULL) { 1995 return 0; 1996 } 1997 const int length = inner_class_list->length(); 1998 if (length % inner_class_next_offset == 0) { 1999 return 0; 2000 } 2001 const int index = length - enclosing_method_attribute_size; 2002 assert(offset < enclosing_method_attribute_size, "invalid offset"); 2003 return inner_class_list->at(index + offset); 2004 } 2005 2006 void InstanceKlass::set_enclosing_method_indices(u2 class_index, 2007 u2 method_index) { 2008 Array<jushort>* inner_class_list = inner_classes(); 2009 assert (inner_class_list != NULL, "_inner_classes list is not set up"); 2010 int length = inner_class_list->length(); 2011 if (length % inner_class_next_offset == enclosing_method_attribute_size) { 2012 int index = length - enclosing_method_attribute_size; 2013 inner_class_list->at_put( 2014 index + enclosing_method_class_index_offset, class_index); 2015 inner_class_list->at_put( 2016 index + enclosing_method_method_index_offset, method_index); 2017 } 2018 } 2019 2020 // Lookup or create a jmethodID. 2021 // This code is called by the VMThread and JavaThreads so the 2022 // locking has to be done very carefully to avoid deadlocks 2023 // and/or other cache consistency problems. 2024 // 2025 jmethodID InstanceKlass::get_jmethod_id(const methodHandle& method_h) { 2026 size_t idnum = (size_t)method_h->method_idnum(); 2027 jmethodID* jmeths = methods_jmethod_ids_acquire(); 2028 size_t length = 0; 2029 jmethodID id = NULL; 2030 2031 // We use a double-check locking idiom here because this cache is 2032 // performance sensitive. In the normal system, this cache only 2033 // transitions from NULL to non-NULL which is safe because we use 2034 // release_set_methods_jmethod_ids() to advertise the new cache. 2035 // A partially constructed cache should never be seen by a racing 2036 // thread. We also use release_store() to save a new jmethodID 2037 // in the cache so a partially constructed jmethodID should never be 2038 // seen either. Cache reads of existing jmethodIDs proceed without a 2039 // lock, but cache writes of a new jmethodID requires uniqueness and 2040 // creation of the cache itself requires no leaks so a lock is 2041 // generally acquired in those two cases. 2042 // 2043 // If the RedefineClasses() API has been used, then this cache can 2044 // grow and we'll have transitions from non-NULL to bigger non-NULL. 2045 // Cache creation requires no leaks and we require safety between all 2046 // cache accesses and freeing of the old cache so a lock is generally 2047 // acquired when the RedefineClasses() API has been used. 2048 2049 if (jmeths != NULL) { 2050 // the cache already exists 2051 if (!idnum_can_increment()) { 2052 // the cache can't grow so we can just get the current values 2053 get_jmethod_id_length_value(jmeths, idnum, &length, &id); 2054 } else { 2055 // cache can grow so we have to be more careful 2056 if (Threads::number_of_threads() == 0 || 2057 SafepointSynchronize::is_at_safepoint()) { 2058 // we're single threaded or at a safepoint - no locking needed 2059 get_jmethod_id_length_value(jmeths, idnum, &length, &id); 2060 } else { 2061 MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag); 2062 get_jmethod_id_length_value(jmeths, idnum, &length, &id); 2063 } 2064 } 2065 } 2066 // implied else: 2067 // we need to allocate a cache so default length and id values are good 2068 2069 if (jmeths == NULL || // no cache yet 2070 length <= idnum || // cache is too short 2071 id == NULL) { // cache doesn't contain entry 2072 2073 // This function can be called by the VMThread so we have to do all 2074 // things that might block on a safepoint before grabbing the lock. 2075 // Otherwise, we can deadlock with the VMThread or have a cache 2076 // consistency issue. These vars keep track of what we might have 2077 // to free after the lock is dropped. 2078 jmethodID to_dealloc_id = NULL; 2079 jmethodID* to_dealloc_jmeths = NULL; 2080 2081 // may not allocate new_jmeths or use it if we allocate it 2082 jmethodID* new_jmeths = NULL; 2083 if (length <= idnum) { 2084 // allocate a new cache that might be used 2085 size_t size = MAX2(idnum+1, (size_t)idnum_allocated_count()); 2086 new_jmeths = NEW_C_HEAP_ARRAY(jmethodID, size+1, mtClass); 2087 memset(new_jmeths, 0, (size+1)*sizeof(jmethodID)); 2088 // cache size is stored in element[0], other elements offset by one 2089 new_jmeths[0] = (jmethodID)size; 2090 } 2091 2092 // allocate a new jmethodID that might be used 2093 jmethodID new_id = NULL; 2094 if (method_h->is_old() && !method_h->is_obsolete()) { 2095 // The method passed in is old (but not obsolete), we need to use the current version 2096 Method* current_method = method_with_idnum((int)idnum); 2097 assert(current_method != NULL, "old and but not obsolete, so should exist"); 2098 new_id = Method::make_jmethod_id(class_loader_data(), current_method); 2099 } else { 2100 // It is the current version of the method or an obsolete method, 2101 // use the version passed in 2102 new_id = Method::make_jmethod_id(class_loader_data(), method_h()); 2103 } 2104 2105 if (Threads::number_of_threads() == 0 || 2106 SafepointSynchronize::is_at_safepoint()) { 2107 // we're single threaded or at a safepoint - no locking needed 2108 id = get_jmethod_id_fetch_or_update(idnum, new_id, new_jmeths, 2109 &to_dealloc_id, &to_dealloc_jmeths); 2110 } else { 2111 MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag); 2112 id = get_jmethod_id_fetch_or_update(idnum, new_id, new_jmeths, 2113 &to_dealloc_id, &to_dealloc_jmeths); 2114 } 2115 2116 // The lock has been dropped so we can free resources. 2117 // Free up either the old cache or the new cache if we allocated one. 2118 if (to_dealloc_jmeths != NULL) { 2119 FreeHeap(to_dealloc_jmeths); 2120 } 2121 // free up the new ID since it wasn't needed 2122 if (to_dealloc_id != NULL) { 2123 Method::destroy_jmethod_id(class_loader_data(), to_dealloc_id); 2124 } 2125 } 2126 return id; 2127 } 2128 2129 // Figure out how many jmethodIDs haven't been allocated, and make 2130 // sure space for them is pre-allocated. This makes getting all 2131 // method ids much, much faster with classes with more than 8 2132 // methods, and has a *substantial* effect on performance with jvmti 2133 // code that loads all jmethodIDs for all classes. 2134 void InstanceKlass::ensure_space_for_methodids(int start_offset) { 2135 int new_jmeths = 0; 2136 int length = methods()->length(); 2137 for (int index = start_offset; index < length; index++) { 2138 Method* m = methods()->at(index); 2139 jmethodID id = m->find_jmethod_id_or_null(); 2140 if (id == NULL) { 2141 new_jmeths++; 2142 } 2143 } 2144 if (new_jmeths != 0) { 2145 Method::ensure_jmethod_ids(class_loader_data(), new_jmeths); 2146 } 2147 } 2148 2149 // Common code to fetch the jmethodID from the cache or update the 2150 // cache with the new jmethodID. This function should never do anything 2151 // that causes the caller to go to a safepoint or we can deadlock with 2152 // the VMThread or have cache consistency issues. 2153 // 2154 jmethodID InstanceKlass::get_jmethod_id_fetch_or_update( 2155 size_t idnum, jmethodID new_id, 2156 jmethodID* new_jmeths, jmethodID* to_dealloc_id_p, 2157 jmethodID** to_dealloc_jmeths_p) { 2158 assert(new_id != NULL, "sanity check"); 2159 assert(to_dealloc_id_p != NULL, "sanity check"); 2160 assert(to_dealloc_jmeths_p != NULL, "sanity check"); 2161 assert(Threads::number_of_threads() == 0 || 2162 SafepointSynchronize::is_at_safepoint() || 2163 JmethodIdCreation_lock->owned_by_self(), "sanity check"); 2164 2165 // reacquire the cache - we are locked, single threaded or at a safepoint 2166 jmethodID* jmeths = methods_jmethod_ids_acquire(); 2167 jmethodID id = NULL; 2168 size_t length = 0; 2169 2170 if (jmeths == NULL || // no cache yet 2171 (length = (size_t)jmeths[0]) <= idnum) { // cache is too short 2172 if (jmeths != NULL) { 2173 // copy any existing entries from the old cache 2174 for (size_t index = 0; index < length; index++) { 2175 new_jmeths[index+1] = jmeths[index+1]; 2176 } 2177 *to_dealloc_jmeths_p = jmeths; // save old cache for later delete 2178 } 2179 release_set_methods_jmethod_ids(jmeths = new_jmeths); 2180 } else { 2181 // fetch jmethodID (if any) from the existing cache 2182 id = jmeths[idnum+1]; 2183 *to_dealloc_jmeths_p = new_jmeths; // save new cache for later delete 2184 } 2185 if (id == NULL) { 2186 // No matching jmethodID in the existing cache or we have a new 2187 // cache or we just grew the cache. This cache write is done here 2188 // by the first thread to win the foot race because a jmethodID 2189 // needs to be unique once it is generally available. 2190 id = new_id; 2191 2192 // The jmethodID cache can be read while unlocked so we have to 2193 // make sure the new jmethodID is complete before installing it 2194 // in the cache. 2195 Atomic::release_store(&jmeths[idnum+1], id); 2196 } else { 2197 *to_dealloc_id_p = new_id; // save new id for later delete 2198 } 2199 return id; 2200 } 2201 2202 2203 // Common code to get the jmethodID cache length and the jmethodID 2204 // value at index idnum if there is one. 2205 // 2206 void InstanceKlass::get_jmethod_id_length_value(jmethodID* cache, 2207 size_t idnum, size_t *length_p, jmethodID* id_p) { 2208 assert(cache != NULL, "sanity check"); 2209 assert(length_p != NULL, "sanity check"); 2210 assert(id_p != NULL, "sanity check"); 2211 2212 // cache size is stored in element[0], other elements offset by one 2213 *length_p = (size_t)cache[0]; 2214 if (*length_p <= idnum) { // cache is too short 2215 *id_p = NULL; 2216 } else { 2217 *id_p = cache[idnum+1]; // fetch jmethodID (if any) 2218 } 2219 } 2220 2221 2222 // Lookup a jmethodID, NULL if not found. Do no blocking, no allocations, no handles 2223 jmethodID InstanceKlass::jmethod_id_or_null(Method* method) { 2224 size_t idnum = (size_t)method->method_idnum(); 2225 jmethodID* jmeths = methods_jmethod_ids_acquire(); 2226 size_t length; // length assigned as debugging crumb 2227 jmethodID id = NULL; 2228 if (jmeths != NULL && // If there is a cache 2229 (length = (size_t)jmeths[0]) > idnum) { // and if it is long enough, 2230 id = jmeths[idnum+1]; // Look up the id (may be NULL) 2231 } 2232 return id; 2233 } 2234 2235 inline DependencyContext InstanceKlass::dependencies() { 2236 DependencyContext dep_context(&_dep_context, &_dep_context_last_cleaned); 2237 return dep_context; 2238 } 2239 2240 int InstanceKlass::mark_dependent_nmethods(KlassDepChange& changes) { 2241 return dependencies().mark_dependent_nmethods(changes); 2242 } 2243 2244 void InstanceKlass::add_dependent_nmethod(nmethod* nm) { 2245 dependencies().add_dependent_nmethod(nm); 2246 } 2247 2248 void InstanceKlass::remove_dependent_nmethod(nmethod* nm) { 2249 dependencies().remove_dependent_nmethod(nm); 2250 } 2251 2252 void InstanceKlass::clean_dependency_context() { 2253 dependencies().clean_unloading_dependents(); 2254 } 2255 2256 #ifndef PRODUCT 2257 void InstanceKlass::print_dependent_nmethods(bool verbose) { 2258 dependencies().print_dependent_nmethods(verbose); 2259 } 2260 2261 bool InstanceKlass::is_dependent_nmethod(nmethod* nm) { 2262 return dependencies().is_dependent_nmethod(nm); 2263 } 2264 #endif //PRODUCT 2265 2266 void InstanceKlass::clean_weak_instanceklass_links() { 2267 clean_implementors_list(); 2268 clean_method_data(); 2269 } 2270 2271 void InstanceKlass::clean_implementors_list() { 2272 assert(is_loader_alive(), "this klass should be live"); 2273 if (is_interface()) { 2274 assert (ClassUnloading, "only called for ClassUnloading"); 2275 for (;;) { 2276 // Use load_acquire due to competing with inserts 2277 Klass* impl = Atomic::load_acquire(adr_implementor()); 2278 if (impl != NULL && !impl->is_loader_alive()) { 2279 // NULL this field, might be an unloaded klass or NULL 2280 Klass* volatile* klass = adr_implementor(); 2281 if (Atomic::cmpxchg(klass, impl, (Klass*)NULL) == impl) { 2282 // Successfully unlinking implementor. 2283 if (log_is_enabled(Trace, class, unload)) { 2284 ResourceMark rm; 2285 log_trace(class, unload)("unlinking class (implementor): %s", impl->external_name()); 2286 } 2287 return; 2288 } 2289 } else { 2290 return; 2291 } 2292 } 2293 } 2294 } 2295 2296 void InstanceKlass::clean_method_data() { 2297 for (int m = 0; m < methods()->length(); m++) { 2298 MethodData* mdo = methods()->at(m)->method_data(); 2299 if (mdo != NULL) { 2300 MutexLocker ml(SafepointSynchronize::is_at_safepoint() ? NULL : mdo->extra_data_lock()); 2301 mdo->clean_method_data(/*always_clean*/false); 2302 } 2303 } 2304 } 2305 2306 bool InstanceKlass::supers_have_passed_fingerprint_checks() { 2307 if (java_super() != NULL && !java_super()->has_passed_fingerprint_check()) { 2308 ResourceMark rm; 2309 log_trace(class, fingerprint)("%s : super %s not fingerprinted", external_name(), java_super()->external_name()); 2310 return false; 2311 } 2312 2313 Array<InstanceKlass*>* local_interfaces = this->local_interfaces(); 2314 if (local_interfaces != NULL) { 2315 int length = local_interfaces->length(); 2316 for (int i = 0; i < length; i++) { 2317 InstanceKlass* intf = local_interfaces->at(i); 2318 if (!intf->has_passed_fingerprint_check()) { 2319 ResourceMark rm; 2320 log_trace(class, fingerprint)("%s : interface %s not fingerprinted", external_name(), intf->external_name()); 2321 return false; 2322 } 2323 } 2324 } 2325 2326 return true; 2327 } 2328 2329 bool InstanceKlass::should_store_fingerprint(bool is_hidden_or_anonymous) { 2330 #if INCLUDE_AOT 2331 // We store the fingerprint into the InstanceKlass only in the following 2 cases: 2332 if (CalculateClassFingerprint) { 2333 // (1) We are running AOT to generate a shared library. 2334 return true; 2335 } 2336 if (Arguments::is_dumping_archive()) { 2337 // (2) We are running -Xshare:dump or -XX:ArchiveClassesAtExit to create a shared archive 2338 return true; 2339 } 2340 if (UseAOT && is_hidden_or_anonymous) { 2341 // (3) We are using AOT code from a shared library and see a hidden or unsafe anonymous class 2342 return true; 2343 } 2344 #endif 2345 2346 // In all other cases we might set the _misc_has_passed_fingerprint_check bit, 2347 // but do not store the 64-bit fingerprint to save space. 2348 return false; 2349 } 2350 2351 bool InstanceKlass::has_stored_fingerprint() const { 2352 #if INCLUDE_AOT 2353 return should_store_fingerprint() || is_shared(); 2354 #else 2355 return false; 2356 #endif 2357 } 2358 2359 uint64_t InstanceKlass::get_stored_fingerprint() const { 2360 address adr = adr_fingerprint(); 2361 if (adr != NULL) { 2362 return (uint64_t)Bytes::get_native_u8(adr); // adr may not be 64-bit aligned 2363 } 2364 return 0; 2365 } 2366 2367 void InstanceKlass::store_fingerprint(uint64_t fingerprint) { 2368 address adr = adr_fingerprint(); 2369 if (adr != NULL) { 2370 Bytes::put_native_u8(adr, (u8)fingerprint); // adr may not be 64-bit aligned 2371 2372 ResourceMark rm; 2373 log_trace(class, fingerprint)("stored as " PTR64_FORMAT " for class %s", fingerprint, external_name()); 2374 } 2375 } 2376 2377 void InstanceKlass::metaspace_pointers_do(MetaspaceClosure* it) { 2378 Klass::metaspace_pointers_do(it); 2379 2380 if (log_is_enabled(Trace, cds)) { 2381 ResourceMark rm; 2382 log_trace(cds)("Iter(InstanceKlass): %p (%s)", this, external_name()); 2383 } 2384 2385 it->push(&_annotations); 2386 it->push((Klass**)&_array_klasses); 2387 it->push(&_constants); 2388 it->push(&_inner_classes); 2389 #if INCLUDE_JVMTI 2390 it->push(&_previous_versions); 2391 #endif 2392 it->push(&_methods); 2393 it->push(&_default_methods); 2394 it->push(&_local_interfaces); 2395 it->push(&_transitive_interfaces); 2396 it->push(&_method_ordering); 2397 it->push(&_default_vtable_indices); 2398 it->push(&_fields); 2399 2400 if (itable_length() > 0) { 2401 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable(); 2402 int method_table_offset_in_words = ioe->offset()/wordSize; 2403 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words()) 2404 / itableOffsetEntry::size(); 2405 2406 for (int i = 0; i < nof_interfaces; i ++, ioe ++) { 2407 if (ioe->interface_klass() != NULL) { 2408 it->push(ioe->interface_klass_addr()); 2409 itableMethodEntry* ime = ioe->first_method_entry(this); 2410 int n = klassItable::method_count_for_interface(ioe->interface_klass()); 2411 for (int index = 0; index < n; index ++) { 2412 it->push(ime[index].method_addr()); 2413 } 2414 } 2415 } 2416 } 2417 2418 it->push(&_nest_members); 2419 it->push(&_record_components); 2420 } 2421 2422 void InstanceKlass::remove_unshareable_info() { 2423 Klass::remove_unshareable_info(); 2424 2425 if (SystemDictionaryShared::has_class_failed_verification(this)) { 2426 // Classes are attempted to link during dumping and may fail, 2427 // but these classes are still in the dictionary and class list in CLD. 2428 // If the class has failed verification, there is nothing else to remove. 2429 return; 2430 } 2431 2432 // Reset to the 'allocated' state to prevent any premature accessing to 2433 // a shared class at runtime while the class is still being loaded and 2434 // restored. A class' init_state is set to 'loaded' at runtime when it's 2435 // being added to class hierarchy (see SystemDictionary:::add_to_hierarchy()). 2436 _init_state = allocated; 2437 2438 { // Otherwise this needs to take out the Compile_lock. 2439 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint"); 2440 init_implementor(); 2441 } 2442 2443 constants()->remove_unshareable_info(); 2444 2445 for (int i = 0; i < methods()->length(); i++) { 2446 Method* m = methods()->at(i); 2447 m->remove_unshareable_info(); 2448 } 2449 2450 // do array classes also. 2451 if (array_klasses() != NULL) { 2452 array_klasses()->remove_unshareable_info(); 2453 } 2454 2455 // These are not allocated from metaspace. They are safe to set to NULL. 2456 _source_debug_extension = NULL; 2457 _dep_context = NULL; 2458 _osr_nmethods_head = NULL; 2459 #if INCLUDE_JVMTI 2460 _breakpoints = NULL; 2461 _previous_versions = NULL; 2462 _cached_class_file = NULL; 2463 _jvmti_cached_class_field_map = NULL; 2464 #endif 2465 2466 _init_thread = NULL; 2467 _methods_jmethod_ids = NULL; 2468 _jni_ids = NULL; 2469 _oop_map_cache = NULL; 2470 // clear _nest_host to ensure re-load at runtime 2471 _nest_host = NULL; 2472 _package_entry = NULL; 2473 _dep_context_last_cleaned = 0; 2474 } 2475 2476 void InstanceKlass::remove_java_mirror() { 2477 Klass::remove_java_mirror(); 2478 2479 // do array classes also. 2480 if (array_klasses() != NULL) { 2481 array_klasses()->remove_java_mirror(); 2482 } 2483 } 2484 2485 void InstanceKlass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain, 2486 PackageEntry* pkg_entry, TRAPS) { 2487 // SystemDictionary::add_to_hierarchy() sets the init_state to loaded 2488 // before the InstanceKlass is added to the SystemDictionary. Make 2489 // sure the current state is <loaded. 2490 assert(!is_loaded(), "invalid init state"); 2491 set_package(loader_data, pkg_entry, CHECK); 2492 Klass::restore_unshareable_info(loader_data, protection_domain, CHECK); 2493 2494 Array<Method*>* methods = this->methods(); 2495 int num_methods = methods->length(); 2496 for (int index = 0; index < num_methods; ++index) { 2497 methods->at(index)->restore_unshareable_info(CHECK); 2498 } 2499 if (JvmtiExport::has_redefined_a_class()) { 2500 // Reinitialize vtable because RedefineClasses may have changed some 2501 // entries in this vtable for super classes so the CDS vtable might 2502 // point to old or obsolete entries. RedefineClasses doesn't fix up 2503 // vtables in the shared system dictionary, only the main one. 2504 // It also redefines the itable too so fix that too. 2505 vtable().initialize_vtable(false, CHECK); 2506 itable().initialize_itable(false, CHECK); 2507 } 2508 2509 // restore constant pool resolved references 2510 constants()->restore_unshareable_info(CHECK); 2511 2512 if (array_klasses() != NULL) { 2513 // Array classes have null protection domain. 2514 // --> see ArrayKlass::complete_create_array_klass() 2515 ArrayKlass::cast(array_klasses())->restore_unshareable_info(ClassLoaderData::the_null_class_loader_data(), Handle(), CHECK); 2516 } 2517 2518 // Initialize current biased locking state. 2519 if (UseBiasedLocking && BiasedLocking::enabled()) { 2520 set_prototype_header(markWord::biased_locking_prototype()); 2521 } 2522 } 2523 2524 void InstanceKlass::set_shared_class_loader_type(s2 loader_type) { 2525 switch (loader_type) { 2526 case ClassLoader::BOOT_LOADER: 2527 _misc_flags |= _misc_is_shared_boot_class; 2528 break; 2529 case ClassLoader::PLATFORM_LOADER: 2530 _misc_flags |= _misc_is_shared_platform_class; 2531 break; 2532 case ClassLoader::APP_LOADER: 2533 _misc_flags |= _misc_is_shared_app_class; 2534 break; 2535 default: 2536 ShouldNotReachHere(); 2537 break; 2538 } 2539 } 2540 2541 #if INCLUDE_JVMTI 2542 static void clear_all_breakpoints(Method* m) { 2543 m->clear_all_breakpoints(); 2544 } 2545 #endif 2546 2547 void InstanceKlass::unload_class(InstanceKlass* ik) { 2548 // Release dependencies. 2549 ik->dependencies().remove_all_dependents(); 2550 2551 // notify the debugger 2552 if (JvmtiExport::should_post_class_unload()) { 2553 JvmtiExport::post_class_unload(ik); 2554 } 2555 2556 // notify ClassLoadingService of class unload 2557 ClassLoadingService::notify_class_unloaded(ik); 2558 2559 if (Arguments::is_dumping_archive()) { 2560 SystemDictionaryShared::remove_dumptime_info(ik); 2561 } 2562 2563 if (log_is_enabled(Info, class, unload)) { 2564 ResourceMark rm; 2565 log_info(class, unload)("unloading class %s " INTPTR_FORMAT, ik->external_name(), p2i(ik)); 2566 } 2567 2568 Events::log_class_unloading(Thread::current(), ik); 2569 2570 #if INCLUDE_JFR 2571 assert(ik != NULL, "invariant"); 2572 EventClassUnload event; 2573 event.set_unloadedClass(ik); 2574 event.set_definingClassLoader(ik->class_loader_data()); 2575 event.commit(); 2576 #endif 2577 } 2578 2579 static void method_release_C_heap_structures(Method* m) { 2580 m->release_C_heap_structures(); 2581 } 2582 2583 void InstanceKlass::release_C_heap_structures() { 2584 2585 // Clean up C heap 2586 release_C_heap_structures_internal(); 2587 constants()->release_C_heap_structures(); 2588 2589 // Deallocate and call destructors for MDO mutexes 2590 methods_do(method_release_C_heap_structures); 2591 } 2592 2593 void InstanceKlass::release_C_heap_structures_internal() { 2594 Klass::release_C_heap_structures(); 2595 2596 // Can't release the constant pool here because the constant pool can be 2597 // deallocated separately from the InstanceKlass for default methods and 2598 // redefine classes. 2599 2600 // Deallocate oop map cache 2601 if (_oop_map_cache != NULL) { 2602 delete _oop_map_cache; 2603 _oop_map_cache = NULL; 2604 } 2605 2606 // Deallocate JNI identifiers for jfieldIDs 2607 JNIid::deallocate(jni_ids()); 2608 set_jni_ids(NULL); 2609 2610 jmethodID* jmeths = methods_jmethod_ids_acquire(); 2611 if (jmeths != (jmethodID*)NULL) { 2612 release_set_methods_jmethod_ids(NULL); 2613 FreeHeap(jmeths); 2614 } 2615 2616 assert(_dep_context == NULL, 2617 "dependencies should already be cleaned"); 2618 2619 #if INCLUDE_JVMTI 2620 // Deallocate breakpoint records 2621 if (breakpoints() != 0x0) { 2622 methods_do(clear_all_breakpoints); 2623 assert(breakpoints() == 0x0, "should have cleared breakpoints"); 2624 } 2625 2626 // deallocate the cached class file 2627 if (_cached_class_file != NULL) { 2628 os::free(_cached_class_file); 2629 _cached_class_file = NULL; 2630 } 2631 #endif 2632 2633 FREE_C_HEAP_ARRAY(char, _source_debug_extension); 2634 } 2635 2636 void InstanceKlass::set_source_debug_extension(const char* array, int length) { 2637 if (array == NULL) { 2638 _source_debug_extension = NULL; 2639 } else { 2640 // Adding one to the attribute length in order to store a null terminator 2641 // character could cause an overflow because the attribute length is 2642 // already coded with an u4 in the classfile, but in practice, it's 2643 // unlikely to happen. 2644 assert((length+1) > length, "Overflow checking"); 2645 char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass); 2646 for (int i = 0; i < length; i++) { 2647 sde[i] = array[i]; 2648 } 2649 sde[length] = '\0'; 2650 _source_debug_extension = sde; 2651 } 2652 } 2653 2654 const char* InstanceKlass::signature_name() const { 2655 int hash_len = 0; 2656 char hash_buf[40]; 2657 2658 // If this is an unsafe anonymous class, append a hash to make the name unique 2659 if (is_unsafe_anonymous()) { 2660 intptr_t hash = (java_mirror() != NULL) ? java_mirror()->identity_hash() : 0; 2661 jio_snprintf(hash_buf, sizeof(hash_buf), "/" UINTX_FORMAT, (uintx)hash); 2662 hash_len = (int)strlen(hash_buf); 2663 } 2664 2665 // Get the internal name as a c string 2666 const char* src = (const char*) (name()->as_C_string()); 2667 const int src_length = (int)strlen(src); 2668 2669 char* dest = NEW_RESOURCE_ARRAY(char, src_length + hash_len + 3); 2670 2671 // Add L as type indicator 2672 int dest_index = 0; 2673 dest[dest_index++] = JVM_SIGNATURE_CLASS; 2674 2675 // Add the actual class name 2676 for (int src_index = 0; src_index < src_length; ) { 2677 dest[dest_index++] = src[src_index++]; 2678 } 2679 2680 if (is_hidden()) { // Replace the last '+' with a '.'. 2681 for (int index = (int)src_length; index > 0; index--) { 2682 if (dest[index] == '+') { 2683 dest[index] = JVM_SIGNATURE_DOT; 2684 break; 2685 } 2686 } 2687 } 2688 2689 // If we have a hash, append it 2690 for (int hash_index = 0; hash_index < hash_len; ) { 2691 dest[dest_index++] = hash_buf[hash_index++]; 2692 } 2693 2694 // Add the semicolon and the NULL 2695 dest[dest_index++] = JVM_SIGNATURE_ENDCLASS; 2696 dest[dest_index] = '\0'; 2697 return dest; 2698 } 2699 2700 ModuleEntry* InstanceKlass::module() const { 2701 // For an unsafe anonymous class return the host class' module 2702 if (is_unsafe_anonymous()) { 2703 assert(unsafe_anonymous_host() != NULL, "unsafe anonymous class must have a host class"); 2704 return unsafe_anonymous_host()->module(); 2705 } 2706 2707 if (is_hidden() && 2708 in_unnamed_package() && 2709 class_loader_data()->has_class_mirror_holder()) { 2710 // For a non-strong hidden class defined to an unnamed package, 2711 // its (class held) CLD will not have an unnamed module created for it. 2712 // Two choices to find the correct ModuleEntry: 2713 // 1. If hidden class is within a nest, use nest host's module 2714 // 2. Find the unnamed module off from the class loader 2715 // For now option #2 is used since a nest host is not set until 2716 // after the instance class is created in jvm_lookup_define_class(). 2717 if (class_loader_data()->is_boot_class_loader_data()) { 2718 return ClassLoaderData::the_null_class_loader_data()->unnamed_module(); 2719 } else { 2720 oop module = java_lang_ClassLoader::unnamedModule(class_loader_data()->class_loader()); 2721 assert(java_lang_Module::is_instance(module), "Not an instance of java.lang.Module"); 2722 return java_lang_Module::module_entry(module); 2723 } 2724 } 2725 2726 // Class is in a named package 2727 if (!in_unnamed_package()) { 2728 return _package_entry->module(); 2729 } 2730 2731 // Class is in an unnamed package, return its loader's unnamed module 2732 return class_loader_data()->unnamed_module(); 2733 } 2734 2735 void InstanceKlass::set_package(ClassLoaderData* loader_data, PackageEntry* pkg_entry, TRAPS) { 2736 2737 // ensure java/ packages only loaded by boot or platform builtin loaders 2738 // not needed for shared class since CDS does not archive prohibited classes. 2739 if (!is_shared()) { 2740 check_prohibited_package(name(), loader_data, CHECK); 2741 } 2742 2743 TempNewSymbol pkg_name = pkg_entry != NULL ? pkg_entry->name() : ClassLoader::package_from_class_name(name()); 2744 2745 if (pkg_name != NULL && loader_data != NULL) { 2746 2747 // Find in class loader's package entry table. 2748 _package_entry = pkg_entry != NULL ? pkg_entry : loader_data->packages()->lookup_only(pkg_name); 2749 2750 // If the package name is not found in the loader's package 2751 // entry table, it is an indication that the package has not 2752 // been defined. Consider it defined within the unnamed module. 2753 if (_package_entry == NULL) { 2754 2755 if (!ModuleEntryTable::javabase_defined()) { 2756 // Before java.base is defined during bootstrapping, define all packages in 2757 // the java.base module. If a non-java.base package is erroneously placed 2758 // in the java.base module it will be caught later when java.base 2759 // is defined by ModuleEntryTable::verify_javabase_packages check. 2760 assert(ModuleEntryTable::javabase_moduleEntry() != NULL, JAVA_BASE_NAME " module is NULL"); 2761 _package_entry = loader_data->packages()->lookup(pkg_name, ModuleEntryTable::javabase_moduleEntry()); 2762 } else { 2763 assert(loader_data->unnamed_module() != NULL, "unnamed module is NULL"); 2764 _package_entry = loader_data->packages()->lookup(pkg_name, 2765 loader_data->unnamed_module()); 2766 } 2767 2768 // A package should have been successfully created 2769 DEBUG_ONLY(ResourceMark rm(THREAD)); 2770 assert(_package_entry != NULL, "Package entry for class %s not found, loader %s", 2771 name()->as_C_string(), loader_data->loader_name_and_id()); 2772 } 2773 2774 if (log_is_enabled(Debug, module)) { 2775 ResourceMark rm(THREAD); 2776 ModuleEntry* m = _package_entry->module(); 2777 log_trace(module)("Setting package: class: %s, package: %s, loader: %s, module: %s", 2778 external_name(), 2779 pkg_name->as_C_string(), 2780 loader_data->loader_name_and_id(), 2781 (m->is_named() ? m->name()->as_C_string() : UNNAMED_MODULE)); 2782 } 2783 } else { 2784 ResourceMark rm(THREAD); 2785 log_trace(module)("Setting package: class: %s, package: unnamed, loader: %s, module: %s", 2786 external_name(), 2787 (loader_data != NULL) ? loader_data->loader_name_and_id() : "NULL", 2788 UNNAMED_MODULE); 2789 } 2790 } 2791 2792 // Function set_classpath_index checks if the package of the InstanceKlass is in the 2793 // boot loader's package entry table. If so, then it sets the classpath_index 2794 // in the package entry record. 2795 // 2796 // The classpath_index field is used to find the entry on the boot loader class 2797 // path for packages with classes loaded by the boot loader from -Xbootclasspath/a 2798 // in an unnamed module. It is also used to indicate (for all packages whose 2799 // classes are loaded by the boot loader) that at least one of the package's 2800 // classes has been loaded. 2801 void InstanceKlass::set_classpath_index(s2 path_index, TRAPS) { 2802 if (_package_entry != NULL) { 2803 DEBUG_ONLY(PackageEntryTable* pkg_entry_tbl = ClassLoaderData::the_null_class_loader_data()->packages();) 2804 assert(pkg_entry_tbl->lookup_only(_package_entry->name()) == _package_entry, "Should be same"); 2805 assert(path_index != -1, "Unexpected classpath_index"); 2806 _package_entry->set_classpath_index(path_index); 2807 } 2808 } 2809 2810 // different versions of is_same_class_package 2811 2812 bool InstanceKlass::is_same_class_package(const Klass* class2) const { 2813 oop classloader1 = this->class_loader(); 2814 PackageEntry* classpkg1 = this->package(); 2815 if (class2->is_objArray_klass()) { 2816 class2 = ObjArrayKlass::cast(class2)->bottom_klass(); 2817 } 2818 2819 oop classloader2; 2820 PackageEntry* classpkg2; 2821 if (class2->is_instance_klass()) { 2822 classloader2 = class2->class_loader(); 2823 classpkg2 = class2->package(); 2824 } else { 2825 assert(class2->is_typeArray_klass(), "should be type array"); 2826 classloader2 = NULL; 2827 classpkg2 = NULL; 2828 } 2829 2830 // Same package is determined by comparing class loader 2831 // and package entries. Both must be the same. This rule 2832 // applies even to classes that are defined in the unnamed 2833 // package, they still must have the same class loader. 2834 if ((classloader1 == classloader2) && (classpkg1 == classpkg2)) { 2835 return true; 2836 } 2837 2838 return false; 2839 } 2840 2841 // return true if this class and other_class are in the same package. Classloader 2842 // and classname information is enough to determine a class's package 2843 bool InstanceKlass::is_same_class_package(oop other_class_loader, 2844 const Symbol* other_class_name) const { 2845 if (class_loader() != other_class_loader) { 2846 return false; 2847 } 2848 if (name()->fast_compare(other_class_name) == 0) { 2849 return true; 2850 } 2851 2852 { 2853 ResourceMark rm; 2854 2855 bool bad_class_name = false; 2856 TempNewSymbol other_pkg = ClassLoader::package_from_class_name(other_class_name, &bad_class_name); 2857 if (bad_class_name) { 2858 return false; 2859 } 2860 // Check that package_from_class_name() returns NULL, not "", if there is no package. 2861 assert(other_pkg == NULL || other_pkg->utf8_length() > 0, "package name is empty string"); 2862 2863 const Symbol* const this_package_name = 2864 this->package() != NULL ? this->package()->name() : NULL; 2865 2866 if (this_package_name == NULL || other_pkg == NULL) { 2867 // One of the two doesn't have a package. Only return true if the other 2868 // one also doesn't have a package. 2869 return this_package_name == other_pkg; 2870 } 2871 2872 // Check if package is identical 2873 return this_package_name->fast_compare(other_pkg) == 0; 2874 } 2875 } 2876 2877 // Returns true iff super_method can be overridden by a method in targetclassname 2878 // See JLS 3rd edition 8.4.6.1 2879 // Assumes name-signature match 2880 // "this" is InstanceKlass of super_method which must exist 2881 // note that the InstanceKlass of the method in the targetclassname has not always been created yet 2882 bool InstanceKlass::is_override(const methodHandle& super_method, Handle targetclassloader, Symbol* targetclassname, TRAPS) { 2883 // Private methods can not be overridden 2884 if (super_method->is_private()) { 2885 return false; 2886 } 2887 // If super method is accessible, then override 2888 if ((super_method->is_protected()) || 2889 (super_method->is_public())) { 2890 return true; 2891 } 2892 // Package-private methods are not inherited outside of package 2893 assert(super_method->is_package_private(), "must be package private"); 2894 return(is_same_class_package(targetclassloader(), targetclassname)); 2895 } 2896 2897 // Only boot and platform class loaders can define classes in "java/" packages. 2898 void InstanceKlass::check_prohibited_package(Symbol* class_name, 2899 ClassLoaderData* loader_data, 2900 TRAPS) { 2901 if (!loader_data->is_boot_class_loader_data() && 2902 !loader_data->is_platform_class_loader_data() && 2903 class_name != NULL) { 2904 ResourceMark rm(THREAD); 2905 char* name = class_name->as_C_string(); 2906 if (strncmp(name, JAVAPKG, JAVAPKG_LEN) == 0 && name[JAVAPKG_LEN] == '/') { 2907 TempNewSymbol pkg_name = ClassLoader::package_from_class_name(class_name); 2908 assert(pkg_name != NULL, "Error in parsing package name starting with 'java/'"); 2909 name = pkg_name->as_C_string(); 2910 const char* class_loader_name = loader_data->loader_name_and_id(); 2911 StringUtils::replace_no_expand(name, "/", "."); 2912 const char* msg_text1 = "Class loader (instance of): "; 2913 const char* msg_text2 = " tried to load prohibited package name: "; 2914 size_t len = strlen(msg_text1) + strlen(class_loader_name) + strlen(msg_text2) + strlen(name) + 1; 2915 char* message = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, len); 2916 jio_snprintf(message, len, "%s%s%s%s", msg_text1, class_loader_name, msg_text2, name); 2917 THROW_MSG(vmSymbols::java_lang_SecurityException(), message); 2918 } 2919 } 2920 return; 2921 } 2922 2923 bool InstanceKlass::find_inner_classes_attr(int* ooff, int* noff, TRAPS) const { 2924 constantPoolHandle i_cp(THREAD, constants()); 2925 for (InnerClassesIterator iter(this); !iter.done(); iter.next()) { 2926 int ioff = iter.inner_class_info_index(); 2927 if (ioff != 0) { 2928 // Check to see if the name matches the class we're looking for 2929 // before attempting to find the class. 2930 if (i_cp->klass_name_at_matches(this, ioff)) { 2931 Klass* inner_klass = i_cp->klass_at(ioff, CHECK_false); 2932 if (this == inner_klass) { 2933 *ooff = iter.outer_class_info_index(); 2934 *noff = iter.inner_name_index(); 2935 return true; 2936 } 2937 } 2938 } 2939 } 2940 return false; 2941 } 2942 2943 InstanceKlass* InstanceKlass::compute_enclosing_class(bool* inner_is_member, TRAPS) const { 2944 InstanceKlass* outer_klass = NULL; 2945 *inner_is_member = false; 2946 int ooff = 0, noff = 0; 2947 bool has_inner_classes_attr = find_inner_classes_attr(&ooff, &noff, THREAD); 2948 if (has_inner_classes_attr) { 2949 constantPoolHandle i_cp(THREAD, constants()); 2950 if (ooff != 0) { 2951 Klass* ok = i_cp->klass_at(ooff, CHECK_NULL); 2952 outer_klass = InstanceKlass::cast(ok); 2953 *inner_is_member = true; 2954 } 2955 if (NULL == outer_klass) { 2956 // It may be a local or anonymous class; try for that. 2957 int encl_method_class_idx = enclosing_method_class_index(); 2958 if (encl_method_class_idx != 0) { 2959 Klass* ok = i_cp->klass_at(encl_method_class_idx, CHECK_NULL); 2960 outer_klass = InstanceKlass::cast(ok); 2961 *inner_is_member = false; 2962 } 2963 } 2964 } 2965 2966 // If no inner class attribute found for this class. 2967 if (NULL == outer_klass) return NULL; 2968 2969 // Throws an exception if outer klass has not declared k as an inner klass 2970 // We need evidence that each klass knows about the other, or else 2971 // the system could allow a spoof of an inner class to gain access rights. 2972 Reflection::check_for_inner_class(outer_klass, this, *inner_is_member, CHECK_NULL); 2973 return outer_klass; 2974 } 2975 2976 jint InstanceKlass::compute_modifier_flags(TRAPS) const { 2977 jint access = access_flags().as_int(); 2978 2979 // But check if it happens to be member class. 2980 InnerClassesIterator iter(this); 2981 for (; !iter.done(); iter.next()) { 2982 int ioff = iter.inner_class_info_index(); 2983 // Inner class attribute can be zero, skip it. 2984 // Strange but true: JVM spec. allows null inner class refs. 2985 if (ioff == 0) continue; 2986 2987 // only look at classes that are already loaded 2988 // since we are looking for the flags for our self. 2989 Symbol* inner_name = constants()->klass_name_at(ioff); 2990 if (name() == inner_name) { 2991 // This is really a member class. 2992 access = iter.inner_access_flags(); 2993 break; 2994 } 2995 } 2996 // Remember to strip ACC_SUPER bit 2997 return (access & (~JVM_ACC_SUPER)) & JVM_ACC_WRITTEN_FLAGS; 2998 } 2999 3000 jint InstanceKlass::jvmti_class_status() const { 3001 jint result = 0; 3002 3003 if (is_linked()) { 3004 result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED; 3005 } 3006 3007 if (is_initialized()) { 3008 assert(is_linked(), "Class status is not consistent"); 3009 result |= JVMTI_CLASS_STATUS_INITIALIZED; 3010 } 3011 if (is_in_error_state()) { 3012 result |= JVMTI_CLASS_STATUS_ERROR; 3013 } 3014 return result; 3015 } 3016 3017 Method* InstanceKlass::method_at_itable(Klass* holder, int index, TRAPS) { 3018 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable(); 3019 int method_table_offset_in_words = ioe->offset()/wordSize; 3020 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words()) 3021 / itableOffsetEntry::size(); 3022 3023 for (int cnt = 0 ; ; cnt ++, ioe ++) { 3024 // If the interface isn't implemented by the receiver class, 3025 // the VM should throw IncompatibleClassChangeError. 3026 if (cnt >= nof_interfaces) { 3027 ResourceMark rm(THREAD); 3028 stringStream ss; 3029 bool same_module = (module() == holder->module()); 3030 ss.print("Receiver class %s does not implement " 3031 "the interface %s defining the method to be called " 3032 "(%s%s%s)", 3033 external_name(), holder->external_name(), 3034 (same_module) ? joint_in_module_of_loader(holder) : class_in_module_of_loader(), 3035 (same_module) ? "" : "; ", 3036 (same_module) ? "" : holder->class_in_module_of_loader()); 3037 THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), ss.as_string()); 3038 } 3039 3040 Klass* ik = ioe->interface_klass(); 3041 if (ik == holder) break; 3042 } 3043 3044 itableMethodEntry* ime = ioe->first_method_entry(this); 3045 Method* m = ime[index].method(); 3046 if (m == NULL) { 3047 THROW_NULL(vmSymbols::java_lang_AbstractMethodError()); 3048 } 3049 return m; 3050 } 3051 3052 3053 #if INCLUDE_JVMTI 3054 // update default_methods for redefineclasses for methods that are 3055 // not yet in the vtable due to concurrent subclass define and superinterface 3056 // redefinition 3057 // Note: those in the vtable, should have been updated via adjust_method_entries 3058 void InstanceKlass::adjust_default_methods(bool* trace_name_printed) { 3059 // search the default_methods for uses of either obsolete or EMCP methods 3060 if (default_methods() != NULL) { 3061 for (int index = 0; index < default_methods()->length(); index ++) { 3062 Method* old_method = default_methods()->at(index); 3063 if (old_method == NULL || !old_method->is_old()) { 3064 continue; // skip uninteresting entries 3065 } 3066 assert(!old_method->is_deleted(), "default methods may not be deleted"); 3067 Method* new_method = old_method->get_new_method(); 3068 default_methods()->at_put(index, new_method); 3069 3070 if (log_is_enabled(Info, redefine, class, update)) { 3071 ResourceMark rm; 3072 if (!(*trace_name_printed)) { 3073 log_info(redefine, class, update) 3074 ("adjust: klassname=%s default methods from name=%s", 3075 external_name(), old_method->method_holder()->external_name()); 3076 *trace_name_printed = true; 3077 } 3078 log_debug(redefine, class, update, vtables) 3079 ("default method update: %s(%s) ", 3080 new_method->name()->as_C_string(), new_method->signature()->as_C_string()); 3081 } 3082 } 3083 } 3084 } 3085 #endif // INCLUDE_JVMTI 3086 3087 // On-stack replacement stuff 3088 void InstanceKlass::add_osr_nmethod(nmethod* n) { 3089 assert_lock_strong(CompiledMethod_lock); 3090 #ifndef PRODUCT 3091 if (TieredCompilation) { 3092 nmethod * prev = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), n->comp_level(), true); 3093 assert(prev == NULL || !prev->is_in_use(), 3094 "redundunt OSR recompilation detected. memory leak in CodeCache!"); 3095 } 3096 #endif 3097 // only one compilation can be active 3098 { 3099 assert(n->is_osr_method(), "wrong kind of nmethod"); 3100 n->set_osr_link(osr_nmethods_head()); 3101 set_osr_nmethods_head(n); 3102 // Raise the highest osr level if necessary 3103 if (TieredCompilation) { 3104 Method* m = n->method(); 3105 m->set_highest_osr_comp_level(MAX2(m->highest_osr_comp_level(), n->comp_level())); 3106 } 3107 } 3108 3109 // Get rid of the osr methods for the same bci that have lower levels. 3110 if (TieredCompilation) { 3111 for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) { 3112 nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true); 3113 if (inv != NULL && inv->is_in_use()) { 3114 inv->make_not_entrant(); 3115 } 3116 } 3117 } 3118 } 3119 3120 // Remove osr nmethod from the list. Return true if found and removed. 3121 bool InstanceKlass::remove_osr_nmethod(nmethod* n) { 3122 // This is a short non-blocking critical region, so the no safepoint check is ok. 3123 MutexLocker ml(CompiledMethod_lock->owned_by_self() ? NULL : CompiledMethod_lock 3124 , Mutex::_no_safepoint_check_flag); 3125 assert(n->is_osr_method(), "wrong kind of nmethod"); 3126 nmethod* last = NULL; 3127 nmethod* cur = osr_nmethods_head(); 3128 int max_level = CompLevel_none; // Find the max comp level excluding n 3129 Method* m = n->method(); 3130 // Search for match 3131 bool found = false; 3132 while(cur != NULL && cur != n) { 3133 if (TieredCompilation && m == cur->method()) { 3134 // Find max level before n 3135 max_level = MAX2(max_level, cur->comp_level()); 3136 } 3137 last = cur; 3138 cur = cur->osr_link(); 3139 } 3140 nmethod* next = NULL; 3141 if (cur == n) { 3142 found = true; 3143 next = cur->osr_link(); 3144 if (last == NULL) { 3145 // Remove first element 3146 set_osr_nmethods_head(next); 3147 } else { 3148 last->set_osr_link(next); 3149 } 3150 } 3151 n->set_osr_link(NULL); 3152 if (TieredCompilation) { 3153 cur = next; 3154 while (cur != NULL) { 3155 // Find max level after n 3156 if (m == cur->method()) { 3157 max_level = MAX2(max_level, cur->comp_level()); 3158 } 3159 cur = cur->osr_link(); 3160 } 3161 m->set_highest_osr_comp_level(max_level); 3162 } 3163 return found; 3164 } 3165 3166 int InstanceKlass::mark_osr_nmethods(const Method* m) { 3167 MutexLocker ml(CompiledMethod_lock->owned_by_self() ? NULL : CompiledMethod_lock, 3168 Mutex::_no_safepoint_check_flag); 3169 nmethod* osr = osr_nmethods_head(); 3170 int found = 0; 3171 while (osr != NULL) { 3172 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain"); 3173 if (osr->method() == m) { 3174 osr->mark_for_deoptimization(); 3175 found++; 3176 } 3177 osr = osr->osr_link(); 3178 } 3179 return found; 3180 } 3181 3182 nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const { 3183 MutexLocker ml(CompiledMethod_lock->owned_by_self() ? NULL : CompiledMethod_lock, 3184 Mutex::_no_safepoint_check_flag); 3185 nmethod* osr = osr_nmethods_head(); 3186 nmethod* best = NULL; 3187 while (osr != NULL) { 3188 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain"); 3189 // There can be a time when a c1 osr method exists but we are waiting 3190 // for a c2 version. When c2 completes its osr nmethod we will trash 3191 // the c1 version and only be able to find the c2 version. However 3192 // while we overflow in the c1 code at back branches we don't want to 3193 // try and switch to the same code as we are already running 3194 3195 if (osr->method() == m && 3196 (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) { 3197 if (match_level) { 3198 if (osr->comp_level() == comp_level) { 3199 // Found a match - return it. 3200 return osr; 3201 } 3202 } else { 3203 if (best == NULL || (osr->comp_level() > best->comp_level())) { 3204 if (osr->comp_level() == CompLevel_highest_tier) { 3205 // Found the best possible - return it. 3206 return osr; 3207 } 3208 best = osr; 3209 } 3210 } 3211 } 3212 osr = osr->osr_link(); 3213 } 3214 3215 assert(match_level == false || best == NULL, "shouldn't pick up anything if match_level is set"); 3216 if (best != NULL && best->comp_level() >= comp_level) { 3217 return best; 3218 } 3219 return NULL; 3220 } 3221 3222 // ----------------------------------------------------------------------------------------------------- 3223 // Printing 3224 3225 #ifndef PRODUCT 3226 3227 #define BULLET " - " 3228 3229 static const char* state_names[] = { 3230 "allocated", "loaded", "linked", "being_initialized", "fully_initialized", "initialization_error" 3231 }; 3232 3233 static void print_vtable(intptr_t* start, int len, outputStream* st) { 3234 for (int i = 0; i < len; i++) { 3235 intptr_t e = start[i]; 3236 st->print("%d : " INTPTR_FORMAT, i, e); 3237 if (MetaspaceObj::is_valid((Metadata*)e)) { 3238 st->print(" "); 3239 ((Metadata*)e)->print_value_on(st); 3240 } 3241 st->cr(); 3242 } 3243 } 3244 3245 static void print_vtable(vtableEntry* start, int len, outputStream* st) { 3246 return print_vtable(reinterpret_cast<intptr_t*>(start), len, st); 3247 } 3248 3249 void InstanceKlass::print_on(outputStream* st) const { 3250 assert(is_klass(), "must be klass"); 3251 Klass::print_on(st); 3252 3253 st->print(BULLET"instance size: %d", size_helper()); st->cr(); 3254 st->print(BULLET"klass size: %d", size()); st->cr(); 3255 st->print(BULLET"access: "); access_flags().print_on(st); st->cr(); 3256 st->print(BULLET"state: "); st->print_cr("%s", state_names[_init_state]); 3257 st->print(BULLET"name: "); name()->print_value_on(st); st->cr(); 3258 st->print(BULLET"super: "); Metadata::print_value_on_maybe_null(st, super()); st->cr(); 3259 st->print(BULLET"sub: "); 3260 Klass* sub = subklass(); 3261 int n; 3262 for (n = 0; sub != NULL; n++, sub = sub->next_sibling()) { 3263 if (n < MaxSubklassPrintSize) { 3264 sub->print_value_on(st); 3265 st->print(" "); 3266 } 3267 } 3268 if (n >= MaxSubklassPrintSize) st->print("(" INTX_FORMAT " more klasses...)", n - MaxSubklassPrintSize); 3269 st->cr(); 3270 3271 if (is_interface()) { 3272 st->print_cr(BULLET"nof implementors: %d", nof_implementors()); 3273 if (nof_implementors() == 1) { 3274 st->print_cr(BULLET"implementor: "); 3275 st->print(" "); 3276 implementor()->print_value_on(st); 3277 st->cr(); 3278 } 3279 } 3280 3281 st->print(BULLET"arrays: "); Metadata::print_value_on_maybe_null(st, array_klasses()); st->cr(); 3282 st->print(BULLET"methods: "); methods()->print_value_on(st); st->cr(); 3283 if (Verbose || WizardMode) { 3284 Array<Method*>* method_array = methods(); 3285 for (int i = 0; i < method_array->length(); i++) { 3286 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr(); 3287 } 3288 } 3289 st->print(BULLET"method ordering: "); method_ordering()->print_value_on(st); st->cr(); 3290 st->print(BULLET"default_methods: "); default_methods()->print_value_on(st); st->cr(); 3291 if (Verbose && default_methods() != NULL) { 3292 Array<Method*>* method_array = default_methods(); 3293 for (int i = 0; i < method_array->length(); i++) { 3294 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr(); 3295 } 3296 } 3297 if (default_vtable_indices() != NULL) { 3298 st->print(BULLET"default vtable indices: "); default_vtable_indices()->print_value_on(st); st->cr(); 3299 } 3300 st->print(BULLET"local interfaces: "); local_interfaces()->print_value_on(st); st->cr(); 3301 st->print(BULLET"trans. interfaces: "); transitive_interfaces()->print_value_on(st); st->cr(); 3302 st->print(BULLET"constants: "); constants()->print_value_on(st); st->cr(); 3303 if (class_loader_data() != NULL) { 3304 st->print(BULLET"class loader data: "); 3305 class_loader_data()->print_value_on(st); 3306 st->cr(); 3307 } 3308 st->print(BULLET"unsafe anonymous host class: "); Metadata::print_value_on_maybe_null(st, unsafe_anonymous_host()); st->cr(); 3309 if (source_file_name() != NULL) { 3310 st->print(BULLET"source file: "); 3311 source_file_name()->print_value_on(st); 3312 st->cr(); 3313 } 3314 if (source_debug_extension() != NULL) { 3315 st->print(BULLET"source debug extension: "); 3316 st->print("%s", source_debug_extension()); 3317 st->cr(); 3318 } 3319 st->print(BULLET"class annotations: "); class_annotations()->print_value_on(st); st->cr(); 3320 st->print(BULLET"class type annotations: "); class_type_annotations()->print_value_on(st); st->cr(); 3321 st->print(BULLET"field annotations: "); fields_annotations()->print_value_on(st); st->cr(); 3322 st->print(BULLET"field type annotations: "); fields_type_annotations()->print_value_on(st); st->cr(); 3323 { 3324 bool have_pv = false; 3325 // previous versions are linked together through the InstanceKlass 3326 for (InstanceKlass* pv_node = previous_versions(); 3327 pv_node != NULL; 3328 pv_node = pv_node->previous_versions()) { 3329 if (!have_pv) 3330 st->print(BULLET"previous version: "); 3331 have_pv = true; 3332 pv_node->constants()->print_value_on(st); 3333 } 3334 if (have_pv) st->cr(); 3335 } 3336 3337 if (generic_signature() != NULL) { 3338 st->print(BULLET"generic signature: "); 3339 generic_signature()->print_value_on(st); 3340 st->cr(); 3341 } 3342 st->print(BULLET"inner classes: "); inner_classes()->print_value_on(st); st->cr(); 3343 st->print(BULLET"nest members: "); nest_members()->print_value_on(st); st->cr(); 3344 if (record_components() != NULL) { 3345 st->print(BULLET"record components: "); record_components()->print_value_on(st); st->cr(); 3346 } 3347 if (java_mirror() != NULL) { 3348 st->print(BULLET"java mirror: "); 3349 java_mirror()->print_value_on(st); 3350 st->cr(); 3351 } else { 3352 st->print_cr(BULLET"java mirror: NULL"); 3353 } 3354 st->print(BULLET"vtable length %d (start addr: " INTPTR_FORMAT ")", vtable_length(), p2i(start_of_vtable())); st->cr(); 3355 if (vtable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_vtable(), vtable_length(), st); 3356 st->print(BULLET"itable length %d (start addr: " INTPTR_FORMAT ")", itable_length(), p2i(start_of_itable())); st->cr(); 3357 if (itable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_itable(), itable_length(), st); 3358 st->print_cr(BULLET"---- static fields (%d words):", static_field_size()); 3359 FieldPrinter print_static_field(st); 3360 ((InstanceKlass*)this)->do_local_static_fields(&print_static_field); 3361 st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size()); 3362 FieldPrinter print_nonstatic_field(st); 3363 InstanceKlass* ik = const_cast<InstanceKlass*>(this); 3364 ik->do_nonstatic_fields(&print_nonstatic_field); 3365 3366 st->print(BULLET"non-static oop maps: "); 3367 OopMapBlock* map = start_of_nonstatic_oop_maps(); 3368 OopMapBlock* end_map = map + nonstatic_oop_map_count(); 3369 while (map < end_map) { 3370 st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1)); 3371 map++; 3372 } 3373 st->cr(); 3374 } 3375 3376 #endif //PRODUCT 3377 3378 void InstanceKlass::print_value_on(outputStream* st) const { 3379 assert(is_klass(), "must be klass"); 3380 if (Verbose || WizardMode) access_flags().print_on(st); 3381 name()->print_value_on(st); 3382 } 3383 3384 #ifndef PRODUCT 3385 3386 void FieldPrinter::do_field(fieldDescriptor* fd) { 3387 _st->print(BULLET); 3388 if (_obj == NULL) { 3389 fd->print_on(_st); 3390 _st->cr(); 3391 } else { 3392 fd->print_on_for(_st, _obj); 3393 _st->cr(); 3394 } 3395 } 3396 3397 3398 void InstanceKlass::oop_print_on(oop obj, outputStream* st) { 3399 Klass::oop_print_on(obj, st); 3400 3401 if (this == SystemDictionary::String_klass()) { 3402 typeArrayOop value = java_lang_String::value(obj); 3403 juint length = java_lang_String::length(obj); 3404 if (value != NULL && 3405 value->is_typeArray() && 3406 length <= (juint) value->length()) { 3407 st->print(BULLET"string: "); 3408 java_lang_String::print(obj, st); 3409 st->cr(); 3410 if (!WizardMode) return; // that is enough 3411 } 3412 } 3413 3414 st->print_cr(BULLET"---- fields (total size %d words):", oop_size(obj)); 3415 FieldPrinter print_field(st, obj); 3416 do_nonstatic_fields(&print_field); 3417 3418 if (this == SystemDictionary::Class_klass()) { 3419 st->print(BULLET"signature: "); 3420 java_lang_Class::print_signature(obj, st); 3421 st->cr(); 3422 Klass* mirrored_klass = java_lang_Class::as_Klass(obj); 3423 st->print(BULLET"fake entry for mirror: "); 3424 Metadata::print_value_on_maybe_null(st, mirrored_klass); 3425 st->cr(); 3426 Klass* array_klass = java_lang_Class::array_klass_acquire(obj); 3427 st->print(BULLET"fake entry for array: "); 3428 Metadata::print_value_on_maybe_null(st, array_klass); 3429 st->cr(); 3430 st->print_cr(BULLET"fake entry for oop_size: %d", java_lang_Class::oop_size(obj)); 3431 st->print_cr(BULLET"fake entry for static_oop_field_count: %d", java_lang_Class::static_oop_field_count(obj)); 3432 Klass* real_klass = java_lang_Class::as_Klass(obj); 3433 if (real_klass != NULL && real_klass->is_instance_klass()) { 3434 InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field); 3435 } 3436 } else if (this == SystemDictionary::MethodType_klass()) { 3437 st->print(BULLET"signature: "); 3438 java_lang_invoke_MethodType::print_signature(obj, st); 3439 st->cr(); 3440 } 3441 } 3442 3443 bool InstanceKlass::verify_itable_index(int i) { 3444 int method_count = klassItable::method_count_for_interface(this); 3445 assert(i >= 0 && i < method_count, "index out of bounds"); 3446 return true; 3447 } 3448 3449 #endif //PRODUCT 3450 3451 void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) { 3452 st->print("a "); 3453 name()->print_value_on(st); 3454 obj->print_address_on(st); 3455 if (this == SystemDictionary::String_klass() 3456 && java_lang_String::value(obj) != NULL) { 3457 ResourceMark rm; 3458 int len = java_lang_String::length(obj); 3459 int plen = (len < 24 ? len : 12); 3460 char* str = java_lang_String::as_utf8_string(obj, 0, plen); 3461 st->print(" = \"%s\"", str); 3462 if (len > plen) 3463 st->print("...[%d]", len); 3464 } else if (this == SystemDictionary::Class_klass()) { 3465 Klass* k = java_lang_Class::as_Klass(obj); 3466 st->print(" = "); 3467 if (k != NULL) { 3468 k->print_value_on(st); 3469 } else { 3470 const char* tname = type2name(java_lang_Class::primitive_type(obj)); 3471 st->print("%s", tname ? tname : "type?"); 3472 } 3473 } else if (this == SystemDictionary::MethodType_klass()) { 3474 st->print(" = "); 3475 java_lang_invoke_MethodType::print_signature(obj, st); 3476 } else if (java_lang_boxing_object::is_instance(obj)) { 3477 st->print(" = "); 3478 java_lang_boxing_object::print(obj, st); 3479 } else if (this == SystemDictionary::LambdaForm_klass()) { 3480 oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj); 3481 if (vmentry != NULL) { 3482 st->print(" => "); 3483 vmentry->print_value_on(st); 3484 } 3485 } else if (this == SystemDictionary::MemberName_klass()) { 3486 Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj); 3487 if (vmtarget != NULL) { 3488 st->print(" = "); 3489 vmtarget->print_value_on(st); 3490 } else { 3491 java_lang_invoke_MemberName::clazz(obj)->print_value_on(st); 3492 st->print("."); 3493 java_lang_invoke_MemberName::name(obj)->print_value_on(st); 3494 } 3495 } 3496 } 3497 3498 const char* InstanceKlass::internal_name() const { 3499 return external_name(); 3500 } 3501 3502 void InstanceKlass::print_class_load_logging(ClassLoaderData* loader_data, 3503 const char* module_name, 3504 const ClassFileStream* cfs) const { 3505 if (!log_is_enabled(Info, class, load)) { 3506 return; 3507 } 3508 3509 ResourceMark rm; 3510 LogMessage(class, load) msg; 3511 stringStream info_stream; 3512 3513 // Name and class hierarchy info 3514 info_stream.print("%s", external_name()); 3515 3516 // Source 3517 if (cfs != NULL) { 3518 if (cfs->source() != NULL) { 3519 if (module_name != NULL) { 3520 // When the boot loader created the stream, it didn't know the module name 3521 // yet. Let's format it now. 3522 if (cfs->from_boot_loader_modules_image()) { 3523 info_stream.print(" source: jrt:/%s", module_name); 3524 } else { 3525 info_stream.print(" source: %s", cfs->source()); 3526 } 3527 } else { 3528 info_stream.print(" source: %s", cfs->source()); 3529 } 3530 } else if (loader_data == ClassLoaderData::the_null_class_loader_data()) { 3531 Thread* THREAD = Thread::current(); 3532 Klass* caller = 3533 THREAD->is_Java_thread() 3534 ? ((JavaThread*)THREAD)->security_get_caller_class(1) 3535 : NULL; 3536 // caller can be NULL, for example, during a JVMTI VM_Init hook 3537 if (caller != NULL) { 3538 info_stream.print(" source: instance of %s", caller->external_name()); 3539 } else { 3540 // source is unknown 3541 } 3542 } else { 3543 oop class_loader = loader_data->class_loader(); 3544 info_stream.print(" source: %s", class_loader->klass()->external_name()); 3545 } 3546 } else { 3547 assert(this->is_shared(), "must be"); 3548 if (MetaspaceShared::is_shared_dynamic((void*)this)) { 3549 info_stream.print(" source: shared objects file (top)"); 3550 } else { 3551 info_stream.print(" source: shared objects file"); 3552 } 3553 } 3554 3555 msg.info("%s", info_stream.as_string()); 3556 3557 if (log_is_enabled(Debug, class, load)) { 3558 stringStream debug_stream; 3559 3560 // Class hierarchy info 3561 debug_stream.print(" klass: " INTPTR_FORMAT " super: " INTPTR_FORMAT, 3562 p2i(this), p2i(superklass())); 3563 3564 // Interfaces 3565 if (local_interfaces() != NULL && local_interfaces()->length() > 0) { 3566 debug_stream.print(" interfaces:"); 3567 int length = local_interfaces()->length(); 3568 for (int i = 0; i < length; i++) { 3569 debug_stream.print(" " INTPTR_FORMAT, 3570 p2i(InstanceKlass::cast(local_interfaces()->at(i)))); 3571 } 3572 } 3573 3574 // Class loader 3575 debug_stream.print(" loader: ["); 3576 loader_data->print_value_on(&debug_stream); 3577 debug_stream.print("]"); 3578 3579 // Classfile checksum 3580 if (cfs) { 3581 debug_stream.print(" bytes: %d checksum: %08x", 3582 cfs->length(), 3583 ClassLoader::crc32(0, (const char*)cfs->buffer(), 3584 cfs->length())); 3585 } 3586 3587 msg.debug("%s", debug_stream.as_string()); 3588 } 3589 } 3590 3591 // Verification 3592 3593 class VerifyFieldClosure: public BasicOopIterateClosure { 3594 protected: 3595 template <class T> void do_oop_work(T* p) { 3596 oop obj = RawAccess<>::oop_load(p); 3597 if (!oopDesc::is_oop_or_null(obj)) { 3598 tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p2i(p), p2i(obj)); 3599 Universe::print_on(tty); 3600 guarantee(false, "boom"); 3601 } 3602 } 3603 public: 3604 virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); } 3605 virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); } 3606 }; 3607 3608 void InstanceKlass::verify_on(outputStream* st) { 3609 #ifndef PRODUCT 3610 // Avoid redundant verifies, this really should be in product. 3611 if (_verify_count == Universe::verify_count()) return; 3612 _verify_count = Universe::verify_count(); 3613 #endif 3614 3615 // Verify Klass 3616 Klass::verify_on(st); 3617 3618 // Verify that klass is present in ClassLoaderData 3619 guarantee(class_loader_data()->contains_klass(this), 3620 "this class isn't found in class loader data"); 3621 3622 // Verify vtables 3623 if (is_linked()) { 3624 // $$$ This used to be done only for m/s collections. Doing it 3625 // always seemed a valid generalization. (DLD -- 6/00) 3626 vtable().verify(st); 3627 } 3628 3629 // Verify first subklass 3630 if (subklass() != NULL) { 3631 guarantee(subklass()->is_klass(), "should be klass"); 3632 } 3633 3634 // Verify siblings 3635 Klass* super = this->super(); 3636 Klass* sib = next_sibling(); 3637 if (sib != NULL) { 3638 if (sib == this) { 3639 fatal("subclass points to itself " PTR_FORMAT, p2i(sib)); 3640 } 3641 3642 guarantee(sib->is_klass(), "should be klass"); 3643 guarantee(sib->super() == super, "siblings should have same superklass"); 3644 } 3645 3646 // Verify local interfaces 3647 if (local_interfaces()) { 3648 Array<InstanceKlass*>* local_interfaces = this->local_interfaces(); 3649 for (int j = 0; j < local_interfaces->length(); j++) { 3650 InstanceKlass* e = local_interfaces->at(j); 3651 guarantee(e->is_klass() && e->is_interface(), "invalid local interface"); 3652 } 3653 } 3654 3655 // Verify transitive interfaces 3656 if (transitive_interfaces() != NULL) { 3657 Array<InstanceKlass*>* transitive_interfaces = this->transitive_interfaces(); 3658 for (int j = 0; j < transitive_interfaces->length(); j++) { 3659 InstanceKlass* e = transitive_interfaces->at(j); 3660 guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface"); 3661 } 3662 } 3663 3664 // Verify methods 3665 if (methods() != NULL) { 3666 Array<Method*>* methods = this->methods(); 3667 for (int j = 0; j < methods->length(); j++) { 3668 guarantee(methods->at(j)->is_method(), "non-method in methods array"); 3669 } 3670 for (int j = 0; j < methods->length() - 1; j++) { 3671 Method* m1 = methods->at(j); 3672 Method* m2 = methods->at(j + 1); 3673 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly"); 3674 } 3675 } 3676 3677 // Verify method ordering 3678 if (method_ordering() != NULL) { 3679 Array<int>* method_ordering = this->method_ordering(); 3680 int length = method_ordering->length(); 3681 if (JvmtiExport::can_maintain_original_method_order() || 3682 ((UseSharedSpaces || Arguments::is_dumping_archive()) && length != 0)) { 3683 guarantee(length == methods()->length(), "invalid method ordering length"); 3684 jlong sum = 0; 3685 for (int j = 0; j < length; j++) { 3686 int original_index = method_ordering->at(j); 3687 guarantee(original_index >= 0, "invalid method ordering index"); 3688 guarantee(original_index < length, "invalid method ordering index"); 3689 sum += original_index; 3690 } 3691 // Verify sum of indices 0,1,...,length-1 3692 guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum"); 3693 } else { 3694 guarantee(length == 0, "invalid method ordering length"); 3695 } 3696 } 3697 3698 // Verify default methods 3699 if (default_methods() != NULL) { 3700 Array<Method*>* methods = this->default_methods(); 3701 for (int j = 0; j < methods->length(); j++) { 3702 guarantee(methods->at(j)->is_method(), "non-method in methods array"); 3703 } 3704 for (int j = 0; j < methods->length() - 1; j++) { 3705 Method* m1 = methods->at(j); 3706 Method* m2 = methods->at(j + 1); 3707 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly"); 3708 } 3709 } 3710 3711 // Verify JNI static field identifiers 3712 if (jni_ids() != NULL) { 3713 jni_ids()->verify(this); 3714 } 3715 3716 // Verify other fields 3717 if (array_klasses() != NULL) { 3718 guarantee(array_klasses()->is_klass(), "should be klass"); 3719 } 3720 if (constants() != NULL) { 3721 guarantee(constants()->is_constantPool(), "should be constant pool"); 3722 } 3723 const Klass* anonymous_host = unsafe_anonymous_host(); 3724 if (anonymous_host != NULL) { 3725 guarantee(anonymous_host->is_klass(), "should be klass"); 3726 } 3727 } 3728 3729 void InstanceKlass::oop_verify_on(oop obj, outputStream* st) { 3730 Klass::oop_verify_on(obj, st); 3731 VerifyFieldClosure blk; 3732 obj->oop_iterate(&blk); 3733 } 3734 3735 3736 // JNIid class for jfieldIDs only 3737 // Note to reviewers: 3738 // These JNI functions are just moved over to column 1 and not changed 3739 // in the compressed oops workspace. 3740 JNIid::JNIid(Klass* holder, int offset, JNIid* next) { 3741 _holder = holder; 3742 _offset = offset; 3743 _next = next; 3744 debug_only(_is_static_field_id = false;) 3745 } 3746 3747 3748 JNIid* JNIid::find(int offset) { 3749 JNIid* current = this; 3750 while (current != NULL) { 3751 if (current->offset() == offset) return current; 3752 current = current->next(); 3753 } 3754 return NULL; 3755 } 3756 3757 void JNIid::deallocate(JNIid* current) { 3758 while (current != NULL) { 3759 JNIid* next = current->next(); 3760 delete current; 3761 current = next; 3762 } 3763 } 3764 3765 3766 void JNIid::verify(Klass* holder) { 3767 int first_field_offset = InstanceMirrorKlass::offset_of_static_fields(); 3768 int end_field_offset; 3769 end_field_offset = first_field_offset + (InstanceKlass::cast(holder)->static_field_size() * wordSize); 3770 3771 JNIid* current = this; 3772 while (current != NULL) { 3773 guarantee(current->holder() == holder, "Invalid klass in JNIid"); 3774 #ifdef ASSERT 3775 int o = current->offset(); 3776 if (current->is_static_field_id()) { 3777 guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid"); 3778 } 3779 #endif 3780 current = current->next(); 3781 } 3782 } 3783 3784 void InstanceKlass::set_init_state(ClassState state) { 3785 #ifdef ASSERT 3786 bool good_state = is_shared() ? (_init_state <= state) 3787 : (_init_state < state); 3788 assert(good_state || state == allocated, "illegal state transition"); 3789 #endif 3790 assert(_init_thread == NULL, "should be cleared before state change"); 3791 _init_state = (u1)state; 3792 } 3793 3794 #if INCLUDE_JVMTI 3795 3796 // RedefineClasses() support for previous versions 3797 3798 // Globally, there is at least one previous version of a class to walk 3799 // during class unloading, which is saved because old methods in the class 3800 // are still running. Otherwise the previous version list is cleaned up. 3801 bool InstanceKlass::_has_previous_versions = false; 3802 3803 // Returns true if there are previous versions of a class for class 3804 // unloading only. Also resets the flag to false. purge_previous_version 3805 // will set the flag to true if there are any left, i.e., if there's any 3806 // work to do for next time. This is to avoid the expensive code cache 3807 // walk in CLDG::clean_deallocate_lists(). 3808 bool InstanceKlass::has_previous_versions_and_reset() { 3809 bool ret = _has_previous_versions; 3810 log_trace(redefine, class, iklass, purge)("Class unloading: has_previous_versions = %s", 3811 ret ? "true" : "false"); 3812 _has_previous_versions = false; 3813 return ret; 3814 } 3815 3816 // Purge previous versions before adding new previous versions of the class and 3817 // during class unloading. 3818 void InstanceKlass::purge_previous_version_list() { 3819 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint"); 3820 assert(has_been_redefined(), "Should only be called for main class"); 3821 3822 // Quick exit. 3823 if (previous_versions() == NULL) { 3824 return; 3825 } 3826 3827 // This klass has previous versions so see what we can cleanup 3828 // while it is safe to do so. 3829 3830 int deleted_count = 0; // leave debugging breadcrumbs 3831 int live_count = 0; 3832 ClassLoaderData* loader_data = class_loader_data(); 3833 assert(loader_data != NULL, "should never be null"); 3834 3835 ResourceMark rm; 3836 log_trace(redefine, class, iklass, purge)("%s: previous versions", external_name()); 3837 3838 // previous versions are linked together through the InstanceKlass 3839 InstanceKlass* pv_node = previous_versions(); 3840 InstanceKlass* last = this; 3841 int version = 0; 3842 3843 // check the previous versions list 3844 for (; pv_node != NULL; ) { 3845 3846 ConstantPool* pvcp = pv_node->constants(); 3847 assert(pvcp != NULL, "cp ref was unexpectedly cleared"); 3848 3849 if (!pvcp->on_stack()) { 3850 // If the constant pool isn't on stack, none of the methods 3851 // are executing. Unlink this previous_version. 3852 // The previous version InstanceKlass is on the ClassLoaderData deallocate list 3853 // so will be deallocated during the next phase of class unloading. 3854 log_trace(redefine, class, iklass, purge) 3855 ("previous version " INTPTR_FORMAT " is dead.", p2i(pv_node)); 3856 // For debugging purposes. 3857 pv_node->set_is_scratch_class(); 3858 // Unlink from previous version list. 3859 assert(pv_node->class_loader_data() == loader_data, "wrong loader_data"); 3860 InstanceKlass* next = pv_node->previous_versions(); 3861 pv_node->link_previous_versions(NULL); // point next to NULL 3862 last->link_previous_versions(next); 3863 // Add to the deallocate list after unlinking 3864 loader_data->add_to_deallocate_list(pv_node); 3865 pv_node = next; 3866 deleted_count++; 3867 version++; 3868 continue; 3869 } else { 3870 log_trace(redefine, class, iklass, purge)("previous version " INTPTR_FORMAT " is alive", p2i(pv_node)); 3871 assert(pvcp->pool_holder() != NULL, "Constant pool with no holder"); 3872 guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack"); 3873 live_count++; 3874 // found a previous version for next time we do class unloading 3875 _has_previous_versions = true; 3876 } 3877 3878 // At least one method is live in this previous version. 3879 // Reset dead EMCP methods not to get breakpoints. 3880 // All methods are deallocated when all of the methods for this class are no 3881 // longer running. 3882 Array<Method*>* method_refs = pv_node->methods(); 3883 if (method_refs != NULL) { 3884 log_trace(redefine, class, iklass, purge)("previous methods length=%d", method_refs->length()); 3885 for (int j = 0; j < method_refs->length(); j++) { 3886 Method* method = method_refs->at(j); 3887 3888 if (!method->on_stack()) { 3889 // no breakpoints for non-running methods 3890 if (method->is_running_emcp()) { 3891 method->set_running_emcp(false); 3892 } 3893 } else { 3894 assert (method->is_obsolete() || method->is_running_emcp(), 3895 "emcp method cannot run after emcp bit is cleared"); 3896 log_trace(redefine, class, iklass, purge) 3897 ("purge: %s(%s): prev method @%d in version @%d is alive", 3898 method->name()->as_C_string(), method->signature()->as_C_string(), j, version); 3899 } 3900 } 3901 } 3902 // next previous version 3903 last = pv_node; 3904 pv_node = pv_node->previous_versions(); 3905 version++; 3906 } 3907 log_trace(redefine, class, iklass, purge) 3908 ("previous version stats: live=%d, deleted=%d", live_count, deleted_count); 3909 } 3910 3911 void InstanceKlass::mark_newly_obsolete_methods(Array<Method*>* old_methods, 3912 int emcp_method_count) { 3913 int obsolete_method_count = old_methods->length() - emcp_method_count; 3914 3915 if (emcp_method_count != 0 && obsolete_method_count != 0 && 3916 _previous_versions != NULL) { 3917 // We have a mix of obsolete and EMCP methods so we have to 3918 // clear out any matching EMCP method entries the hard way. 3919 int local_count = 0; 3920 for (int i = 0; i < old_methods->length(); i++) { 3921 Method* old_method = old_methods->at(i); 3922 if (old_method->is_obsolete()) { 3923 // only obsolete methods are interesting 3924 Symbol* m_name = old_method->name(); 3925 Symbol* m_signature = old_method->signature(); 3926 3927 // previous versions are linked together through the InstanceKlass 3928 int j = 0; 3929 for (InstanceKlass* prev_version = _previous_versions; 3930 prev_version != NULL; 3931 prev_version = prev_version->previous_versions(), j++) { 3932 3933 Array<Method*>* method_refs = prev_version->methods(); 3934 for (int k = 0; k < method_refs->length(); k++) { 3935 Method* method = method_refs->at(k); 3936 3937 if (!method->is_obsolete() && 3938 method->name() == m_name && 3939 method->signature() == m_signature) { 3940 // The current RedefineClasses() call has made all EMCP 3941 // versions of this method obsolete so mark it as obsolete 3942 log_trace(redefine, class, iklass, add) 3943 ("%s(%s): flush obsolete method @%d in version @%d", 3944 m_name->as_C_string(), m_signature->as_C_string(), k, j); 3945 3946 method->set_is_obsolete(); 3947 break; 3948 } 3949 } 3950 3951 // The previous loop may not find a matching EMCP method, but 3952 // that doesn't mean that we can optimize and not go any 3953 // further back in the PreviousVersion generations. The EMCP 3954 // method for this generation could have already been made obsolete, 3955 // but there still may be an older EMCP method that has not 3956 // been made obsolete. 3957 } 3958 3959 if (++local_count >= obsolete_method_count) { 3960 // no more obsolete methods so bail out now 3961 break; 3962 } 3963 } 3964 } 3965 } 3966 } 3967 3968 // Save the scratch_class as the previous version if any of the methods are running. 3969 // The previous_versions are used to set breakpoints in EMCP methods and they are 3970 // also used to clean MethodData links to redefined methods that are no longer running. 3971 void InstanceKlass::add_previous_version(InstanceKlass* scratch_class, 3972 int emcp_method_count) { 3973 assert(Thread::current()->is_VM_thread(), 3974 "only VMThread can add previous versions"); 3975 3976 ResourceMark rm; 3977 log_trace(redefine, class, iklass, add) 3978 ("adding previous version ref for %s, EMCP_cnt=%d", scratch_class->external_name(), emcp_method_count); 3979 3980 // Clean out old previous versions for this class 3981 purge_previous_version_list(); 3982 3983 // Mark newly obsolete methods in remaining previous versions. An EMCP method from 3984 // a previous redefinition may be made obsolete by this redefinition. 3985 Array<Method*>* old_methods = scratch_class->methods(); 3986 mark_newly_obsolete_methods(old_methods, emcp_method_count); 3987 3988 // If the constant pool for this previous version of the class 3989 // is not marked as being on the stack, then none of the methods 3990 // in this previous version of the class are on the stack so 3991 // we don't need to add this as a previous version. 3992 ConstantPool* cp_ref = scratch_class->constants(); 3993 if (!cp_ref->on_stack()) { 3994 log_trace(redefine, class, iklass, add)("scratch class not added; no methods are running"); 3995 // For debugging purposes. 3996 scratch_class->set_is_scratch_class(); 3997 scratch_class->class_loader_data()->add_to_deallocate_list(scratch_class); 3998 return; 3999 } 4000 4001 if (emcp_method_count != 0) { 4002 // At least one method is still running, check for EMCP methods 4003 for (int i = 0; i < old_methods->length(); i++) { 4004 Method* old_method = old_methods->at(i); 4005 if (!old_method->is_obsolete() && old_method->on_stack()) { 4006 // if EMCP method (not obsolete) is on the stack, mark as EMCP so that 4007 // we can add breakpoints for it. 4008 4009 // We set the method->on_stack bit during safepoints for class redefinition 4010 // and use this bit to set the is_running_emcp bit. 4011 // After the safepoint, the on_stack bit is cleared and the running emcp 4012 // method may exit. If so, we would set a breakpoint in a method that 4013 // is never reached, but this won't be noticeable to the programmer. 4014 old_method->set_running_emcp(true); 4015 log_trace(redefine, class, iklass, add) 4016 ("EMCP method %s is on_stack " INTPTR_FORMAT, old_method->name_and_sig_as_C_string(), p2i(old_method)); 4017 } else if (!old_method->is_obsolete()) { 4018 log_trace(redefine, class, iklass, add) 4019 ("EMCP method %s is NOT on_stack " INTPTR_FORMAT, old_method->name_and_sig_as_C_string(), p2i(old_method)); 4020 } 4021 } 4022 } 4023 4024 // Add previous version if any methods are still running. 4025 // Set has_previous_version flag for processing during class unloading. 4026 _has_previous_versions = true; 4027 log_trace(redefine, class, iklass, add) ("scratch class added; one of its methods is on_stack."); 4028 assert(scratch_class->previous_versions() == NULL, "shouldn't have a previous version"); 4029 scratch_class->link_previous_versions(previous_versions()); 4030 link_previous_versions(scratch_class); 4031 } // end add_previous_version() 4032 4033 #endif // INCLUDE_JVMTI 4034 4035 Method* InstanceKlass::method_with_idnum(int idnum) { 4036 Method* m = NULL; 4037 if (idnum < methods()->length()) { 4038 m = methods()->at(idnum); 4039 } 4040 if (m == NULL || m->method_idnum() != idnum) { 4041 for (int index = 0; index < methods()->length(); ++index) { 4042 m = methods()->at(index); 4043 if (m->method_idnum() == idnum) { 4044 return m; 4045 } 4046 } 4047 // None found, return null for the caller to handle. 4048 return NULL; 4049 } 4050 return m; 4051 } 4052 4053 4054 Method* InstanceKlass::method_with_orig_idnum(int idnum) { 4055 if (idnum >= methods()->length()) { 4056 return NULL; 4057 } 4058 Method* m = methods()->at(idnum); 4059 if (m != NULL && m->orig_method_idnum() == idnum) { 4060 return m; 4061 } 4062 // Obsolete method idnum does not match the original idnum 4063 for (int index = 0; index < methods()->length(); ++index) { 4064 m = methods()->at(index); 4065 if (m->orig_method_idnum() == idnum) { 4066 return m; 4067 } 4068 } 4069 // None found, return null for the caller to handle. 4070 return NULL; 4071 } 4072 4073 4074 Method* InstanceKlass::method_with_orig_idnum(int idnum, int version) { 4075 InstanceKlass* holder = get_klass_version(version); 4076 if (holder == NULL) { 4077 return NULL; // The version of klass is gone, no method is found 4078 } 4079 Method* method = holder->method_with_orig_idnum(idnum); 4080 return method; 4081 } 4082 4083 #if INCLUDE_JVMTI 4084 JvmtiCachedClassFileData* InstanceKlass::get_cached_class_file() { 4085 return _cached_class_file; 4086 } 4087 4088 jint InstanceKlass::get_cached_class_file_len() { 4089 return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file); 4090 } 4091 4092 unsigned char * InstanceKlass::get_cached_class_file_bytes() { 4093 return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file); 4094 } 4095 #endif