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 // Set biased locking bit for all instances of this class; it will be 509 // cleared if revocation occurs too often for this type 510 if (UseBiasedLocking && BiasedLocking::enabled()) { 511 set_prototype_header(markWord::biased_locking_prototype()); 512 } 513 } 514 515 void InstanceKlass::deallocate_methods(ClassLoaderData* loader_data, 516 Array<Method*>* methods) { 517 if (methods != NULL && methods != Universe::the_empty_method_array() && 518 !methods->is_shared()) { 519 for (int i = 0; i < methods->length(); i++) { 520 Method* method = methods->at(i); 521 if (method == NULL) continue; // maybe null if error processing 522 // Only want to delete methods that are not executing for RedefineClasses. 523 // The previous version will point to them so they're not totally dangling 524 assert (!method->on_stack(), "shouldn't be called with methods on stack"); 525 MetadataFactory::free_metadata(loader_data, method); 526 } 527 MetadataFactory::free_array<Method*>(loader_data, methods); 528 } 529 } 530 531 void InstanceKlass::deallocate_interfaces(ClassLoaderData* loader_data, 532 const Klass* super_klass, 533 Array<InstanceKlass*>* local_interfaces, 534 Array<InstanceKlass*>* transitive_interfaces) { 535 // Only deallocate transitive interfaces if not empty, same as super class 536 // or same as local interfaces. See code in parseClassFile. 537 Array<InstanceKlass*>* ti = transitive_interfaces; 538 if (ti != Universe::the_empty_instance_klass_array() && ti != local_interfaces) { 539 // check that the interfaces don't come from super class 540 Array<InstanceKlass*>* sti = (super_klass == NULL) ? NULL : 541 InstanceKlass::cast(super_klass)->transitive_interfaces(); 542 if (ti != sti && ti != NULL && !ti->is_shared()) { 543 MetadataFactory::free_array<InstanceKlass*>(loader_data, ti); 544 } 545 } 546 547 // local interfaces can be empty 548 if (local_interfaces != Universe::the_empty_instance_klass_array() && 549 local_interfaces != NULL && !local_interfaces->is_shared()) { 550 MetadataFactory::free_array<InstanceKlass*>(loader_data, local_interfaces); 551 } 552 } 553 554 void InstanceKlass::deallocate_record_components(ClassLoaderData* loader_data, 555 Array<RecordComponent*>* record_components) { 556 if (record_components != NULL && !record_components->is_shared()) { 557 for (int i = 0; i < record_components->length(); i++) { 558 RecordComponent* record_component = record_components->at(i); 559 MetadataFactory::free_metadata(loader_data, record_component); 560 } 561 MetadataFactory::free_array<RecordComponent*>(loader_data, record_components); 562 } 563 } 564 565 // This function deallocates the metadata and C heap pointers that the 566 // InstanceKlass points to. 567 void InstanceKlass::deallocate_contents(ClassLoaderData* loader_data) { 568 569 // Orphan the mirror first, CMS thinks it's still live. 570 if (java_mirror() != NULL) { 571 java_lang_Class::set_klass(java_mirror(), NULL); 572 } 573 574 // Also remove mirror from handles 575 loader_data->remove_handle(_java_mirror); 576 577 // Need to take this class off the class loader data list. 578 loader_data->remove_class(this); 579 580 // The array_klass for this class is created later, after error handling. 581 // For class redefinition, we keep the original class so this scratch class 582 // doesn't have an array class. Either way, assert that there is nothing 583 // to deallocate. 584 assert(array_klasses() == NULL, "array classes shouldn't be created for this class yet"); 585 586 // Release C heap allocated data that this points to, which includes 587 // reference counting symbol names. 588 release_C_heap_structures_internal(); 589 590 deallocate_methods(loader_data, methods()); 591 set_methods(NULL); 592 593 deallocate_record_components(loader_data, record_components()); 594 set_record_components(NULL); 595 596 if (method_ordering() != NULL && 597 method_ordering() != Universe::the_empty_int_array() && 598 !method_ordering()->is_shared()) { 599 MetadataFactory::free_array<int>(loader_data, method_ordering()); 600 } 601 set_method_ordering(NULL); 602 603 // default methods can be empty 604 if (default_methods() != NULL && 605 default_methods() != Universe::the_empty_method_array() && 606 !default_methods()->is_shared()) { 607 MetadataFactory::free_array<Method*>(loader_data, default_methods()); 608 } 609 // Do NOT deallocate the default methods, they are owned by superinterfaces. 610 set_default_methods(NULL); 611 612 // default methods vtable indices can be empty 613 if (default_vtable_indices() != NULL && 614 !default_vtable_indices()->is_shared()) { 615 MetadataFactory::free_array<int>(loader_data, default_vtable_indices()); 616 } 617 set_default_vtable_indices(NULL); 618 619 620 // This array is in Klass, but remove it with the InstanceKlass since 621 // this place would be the only caller and it can share memory with transitive 622 // interfaces. 623 if (secondary_supers() != NULL && 624 secondary_supers() != Universe::the_empty_klass_array() && 625 // see comments in compute_secondary_supers about the following cast 626 (address)(secondary_supers()) != (address)(transitive_interfaces()) && 627 !secondary_supers()->is_shared()) { 628 MetadataFactory::free_array<Klass*>(loader_data, secondary_supers()); 629 } 630 set_secondary_supers(NULL); 631 632 deallocate_interfaces(loader_data, super(), local_interfaces(), transitive_interfaces()); 633 set_transitive_interfaces(NULL); 634 set_local_interfaces(NULL); 635 636 if (fields() != NULL && !fields()->is_shared()) { 637 MetadataFactory::free_array<jushort>(loader_data, fields()); 638 } 639 set_fields(NULL, 0); 640 641 // If a method from a redefined class is using this constant pool, don't 642 // delete it, yet. The new class's previous version will point to this. 643 if (constants() != NULL) { 644 assert (!constants()->on_stack(), "shouldn't be called if anything is onstack"); 645 if (!constants()->is_shared()) { 646 MetadataFactory::free_metadata(loader_data, constants()); 647 } 648 // Delete any cached resolution errors for the constant pool 649 SystemDictionary::delete_resolution_error(constants()); 650 651 set_constants(NULL); 652 } 653 654 if (inner_classes() != NULL && 655 inner_classes() != Universe::the_empty_short_array() && 656 !inner_classes()->is_shared()) { 657 MetadataFactory::free_array<jushort>(loader_data, inner_classes()); 658 } 659 set_inner_classes(NULL); 660 661 if (nest_members() != NULL && 662 nest_members() != Universe::the_empty_short_array() && 663 !nest_members()->is_shared()) { 664 MetadataFactory::free_array<jushort>(loader_data, nest_members()); 665 } 666 set_nest_members(NULL); 667 668 // We should deallocate the Annotations instance if it's not in shared spaces. 669 if (annotations() != NULL && !annotations()->is_shared()) { 670 MetadataFactory::free_metadata(loader_data, annotations()); 671 } 672 set_annotations(NULL); 673 674 if (Arguments::is_dumping_archive()) { 675 SystemDictionaryShared::remove_dumptime_info(this); 676 } 677 } 678 679 bool InstanceKlass::should_be_initialized() const { 680 return !is_initialized(); 681 } 682 683 klassItable InstanceKlass::itable() const { 684 return klassItable(const_cast<InstanceKlass*>(this)); 685 } 686 687 void InstanceKlass::eager_initialize(Thread *thread) { 688 if (!EagerInitialization) return; 689 690 if (this->is_not_initialized()) { 691 // abort if the the class has a class initializer 692 if (this->class_initializer() != NULL) return; 693 694 // abort if it is java.lang.Object (initialization is handled in genesis) 695 Klass* super_klass = super(); 696 if (super_klass == NULL) return; 697 698 // abort if the super class should be initialized 699 if (!InstanceKlass::cast(super_klass)->is_initialized()) return; 700 701 // call body to expose the this pointer 702 eager_initialize_impl(); 703 } 704 } 705 706 // JVMTI spec thinks there are signers and protection domain in the 707 // instanceKlass. These accessors pretend these fields are there. 708 // The hprof specification also thinks these fields are in InstanceKlass. 709 oop InstanceKlass::protection_domain() const { 710 // return the protection_domain from the mirror 711 return java_lang_Class::protection_domain(java_mirror()); 712 } 713 714 // To remove these from requires an incompatible change and CCC request. 715 objArrayOop InstanceKlass::signers() const { 716 // return the signers from the mirror 717 return java_lang_Class::signers(java_mirror()); 718 } 719 720 oop InstanceKlass::init_lock() const { 721 // return the init lock from the mirror 722 oop lock = java_lang_Class::init_lock(java_mirror()); 723 // Prevent reordering with any access of initialization state 724 OrderAccess::loadload(); 725 assert((oop)lock != NULL || !is_not_initialized(), // initialized or in_error state 726 "only fully initialized state can have a null lock"); 727 return lock; 728 } 729 730 // Set the initialization lock to null so the object can be GC'ed. Any racing 731 // threads to get this lock will see a null lock and will not lock. 732 // That's okay because they all check for initialized state after getting 733 // the lock and return. 734 void InstanceKlass::fence_and_clear_init_lock() { 735 // make sure previous stores are all done, notably the init_state. 736 OrderAccess::storestore(); 737 java_lang_Class::set_init_lock(java_mirror(), NULL); 738 assert(!is_not_initialized(), "class must be initialized now"); 739 } 740 741 void InstanceKlass::eager_initialize_impl() { 742 EXCEPTION_MARK; 743 HandleMark hm(THREAD); 744 Handle h_init_lock(THREAD, init_lock()); 745 ObjectLocker ol(h_init_lock, THREAD, h_init_lock() != NULL); 746 747 // abort if someone beat us to the initialization 748 if (!is_not_initialized()) return; // note: not equivalent to is_initialized() 749 750 ClassState old_state = init_state(); 751 link_class_impl(THREAD); 752 if (HAS_PENDING_EXCEPTION) { 753 CLEAR_PENDING_EXCEPTION; 754 // Abort if linking the class throws an exception. 755 756 // Use a test to avoid redundantly resetting the state if there's 757 // no change. Set_init_state() asserts that state changes make 758 // progress, whereas here we might just be spinning in place. 759 if (old_state != _init_state) 760 set_init_state(old_state); 761 } else { 762 // linking successfull, mark class as initialized 763 set_init_state(fully_initialized); 764 fence_and_clear_init_lock(); 765 // trace 766 if (log_is_enabled(Info, class, init)) { 767 ResourceMark rm(THREAD); 768 log_info(class, init)("[Initialized %s without side effects]", external_name()); 769 } 770 } 771 } 772 773 774 // See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization 775 // process. The step comments refers to the procedure described in that section. 776 // Note: implementation moved to static method to expose the this pointer. 777 void InstanceKlass::initialize(TRAPS) { 778 if (this->should_be_initialized()) { 779 initialize_impl(CHECK); 780 // Note: at this point the class may be initialized 781 // OR it may be in the state of being initialized 782 // in case of recursive initialization! 783 } else { 784 assert(is_initialized(), "sanity check"); 785 } 786 } 787 788 789 bool InstanceKlass::verify_code(TRAPS) { 790 // 1) Verify the bytecodes 791 return Verifier::verify(this, should_verify_class(), THREAD); 792 } 793 794 void InstanceKlass::link_class(TRAPS) { 795 assert(is_loaded(), "must be loaded"); 796 if (!is_linked()) { 797 link_class_impl(CHECK); 798 } 799 } 800 801 // Called to verify that a class can link during initialization, without 802 // throwing a VerifyError. 803 bool InstanceKlass::link_class_or_fail(TRAPS) { 804 assert(is_loaded(), "must be loaded"); 805 if (!is_linked()) { 806 link_class_impl(CHECK_false); 807 } 808 return is_linked(); 809 } 810 811 bool InstanceKlass::link_class_impl(TRAPS) { 812 if (DumpSharedSpaces && SystemDictionaryShared::has_class_failed_verification(this)) { 813 // This is for CDS dumping phase only -- we use the in_error_state to indicate that 814 // the class has failed verification. Throwing the NoClassDefFoundError here is just 815 // a convenient way to stop repeat attempts to verify the same (bad) class. 816 // 817 // Note that the NoClassDefFoundError is not part of the JLS, and should not be thrown 818 // if we are executing Java code. This is not a problem for CDS dumping phase since 819 // it doesn't execute any Java code. 820 ResourceMark rm(THREAD); 821 Exceptions::fthrow(THREAD_AND_LOCATION, 822 vmSymbols::java_lang_NoClassDefFoundError(), 823 "Class %s, or one of its supertypes, failed class initialization", 824 external_name()); 825 return false; 826 } 827 // return if already verified 828 if (is_linked()) { 829 return true; 830 } 831 832 // Timing 833 // timer handles recursion 834 assert(THREAD->is_Java_thread(), "non-JavaThread in link_class_impl"); 835 JavaThread* jt = (JavaThread*)THREAD; 836 837 // link super class before linking this class 838 Klass* super_klass = super(); 839 if (super_klass != NULL) { 840 if (super_klass->is_interface()) { // check if super class is an interface 841 ResourceMark rm(THREAD); 842 Exceptions::fthrow( 843 THREAD_AND_LOCATION, 844 vmSymbols::java_lang_IncompatibleClassChangeError(), 845 "class %s has interface %s as super class", 846 external_name(), 847 super_klass->external_name() 848 ); 849 return false; 850 } 851 852 InstanceKlass* ik_super = InstanceKlass::cast(super_klass); 853 ik_super->link_class_impl(CHECK_false); 854 } 855 856 // link all interfaces implemented by this class before linking this class 857 Array<InstanceKlass*>* interfaces = local_interfaces(); 858 int num_interfaces = interfaces->length(); 859 for (int index = 0; index < num_interfaces; index++) { 860 InstanceKlass* interk = interfaces->at(index); 861 interk->link_class_impl(CHECK_false); 862 } 863 864 // in case the class is linked in the process of linking its superclasses 865 if (is_linked()) { 866 return true; 867 } 868 869 // trace only the link time for this klass that includes 870 // the verification time 871 PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(), 872 ClassLoader::perf_class_link_selftime(), 873 ClassLoader::perf_classes_linked(), 874 jt->get_thread_stat()->perf_recursion_counts_addr(), 875 jt->get_thread_stat()->perf_timers_addr(), 876 PerfClassTraceTime::CLASS_LINK); 877 878 // verification & rewriting 879 { 880 HandleMark hm(THREAD); 881 Handle h_init_lock(THREAD, init_lock()); 882 ObjectLocker ol(h_init_lock, THREAD, h_init_lock() != NULL); 883 // rewritten will have been set if loader constraint error found 884 // on an earlier link attempt 885 // don't verify or rewrite if already rewritten 886 // 887 888 if (!is_linked()) { 889 if (!is_rewritten()) { 890 { 891 bool verify_ok = verify_code(THREAD); 892 if (!verify_ok) { 893 return false; 894 } 895 } 896 897 // Just in case a side-effect of verify linked this class already 898 // (which can sometimes happen since the verifier loads classes 899 // using custom class loaders, which are free to initialize things) 900 if (is_linked()) { 901 return true; 902 } 903 904 // also sets rewritten 905 rewrite_class(CHECK_false); 906 } else if (is_shared()) { 907 SystemDictionaryShared::check_verification_constraints(this, CHECK_false); 908 } 909 910 // relocate jsrs and link methods after they are all rewritten 911 link_methods(CHECK_false); 912 913 // Initialize the vtable and interface table after 914 // methods have been rewritten since rewrite may 915 // fabricate new Method*s. 916 // also does loader constraint checking 917 // 918 // initialize_vtable and initialize_itable need to be rerun 919 // for a shared class if 920 // 1) the class is loaded by custom class loader or 921 // 2) the class is loaded by built-in class loader but failed to add archived loader constraints 922 bool need_init_table = true; 923 if (is_shared() && SystemDictionaryShared::check_linking_constraints(this, THREAD)) { 924 need_init_table = false; 925 } 926 if (need_init_table) { 927 vtable().initialize_vtable(true, CHECK_false); 928 itable().initialize_itable(true, CHECK_false); 929 } 930 #ifdef ASSERT 931 vtable().verify(tty, true); 932 // In case itable verification is ever added. 933 // itable().verify(tty, true); 934 #endif 935 set_init_state(linked); 936 if (JvmtiExport::should_post_class_prepare()) { 937 Thread *thread = THREAD; 938 assert(thread->is_Java_thread(), "thread->is_Java_thread()"); 939 JvmtiExport::post_class_prepare((JavaThread *) thread, this); 940 } 941 } 942 } 943 return true; 944 } 945 946 // Rewrite the byte codes of all of the methods of a class. 947 // The rewriter must be called exactly once. Rewriting must happen after 948 // verification but before the first method of the class is executed. 949 void InstanceKlass::rewrite_class(TRAPS) { 950 assert(is_loaded(), "must be loaded"); 951 if (is_rewritten()) { 952 assert(is_shared(), "rewriting an unshared class?"); 953 return; 954 } 955 Rewriter::rewrite(this, CHECK); 956 set_rewritten(); 957 } 958 959 // Now relocate and link method entry points after class is rewritten. 960 // This is outside is_rewritten flag. In case of an exception, it can be 961 // executed more than once. 962 void InstanceKlass::link_methods(TRAPS) { 963 int len = methods()->length(); 964 for (int i = len-1; i >= 0; i--) { 965 methodHandle m(THREAD, methods()->at(i)); 966 967 // Set up method entry points for compiler and interpreter . 968 m->link_method(m, CHECK); 969 } 970 } 971 972 // Eagerly initialize superinterfaces that declare default methods (concrete instance: any access) 973 void InstanceKlass::initialize_super_interfaces(TRAPS) { 974 assert (has_nonstatic_concrete_methods(), "caller should have checked this"); 975 for (int i = 0; i < local_interfaces()->length(); ++i) { 976 InstanceKlass* ik = local_interfaces()->at(i); 977 978 // Initialization is depth first search ie. we start with top of the inheritance tree 979 // has_nonstatic_concrete_methods drives searching superinterfaces since it 980 // means has_nonstatic_concrete_methods in its superinterface hierarchy 981 if (ik->has_nonstatic_concrete_methods()) { 982 ik->initialize_super_interfaces(CHECK); 983 } 984 985 // Only initialize() interfaces that "declare" concrete methods. 986 if (ik->should_be_initialized() && ik->declares_nonstatic_concrete_methods()) { 987 ik->initialize(CHECK); 988 } 989 } 990 } 991 992 void InstanceKlass::initialize_impl(TRAPS) { 993 HandleMark hm(THREAD); 994 995 // Make sure klass is linked (verified) before initialization 996 // A class could already be verified, since it has been reflected upon. 997 link_class(CHECK); 998 999 DTRACE_CLASSINIT_PROBE(required, -1); 1000 1001 bool wait = false; 1002 1003 assert(THREAD->is_Java_thread(), "non-JavaThread in initialize_impl"); 1004 JavaThread* jt = (JavaThread*)THREAD; 1005 1006 // refer to the JVM book page 47 for description of steps 1007 // Step 1 1008 { 1009 Handle h_init_lock(THREAD, init_lock()); 1010 ObjectLocker ol(h_init_lock, THREAD, h_init_lock() != NULL); 1011 1012 // Step 2 1013 // If we were to use wait() instead of waitInterruptibly() then 1014 // we might end up throwing IE from link/symbol resolution sites 1015 // that aren't expected to throw. This would wreak havoc. See 6320309. 1016 while (is_being_initialized() && !is_reentrant_initialization(jt)) { 1017 wait = true; 1018 jt->set_class_to_be_initialized(this); 1019 ol.wait_uninterruptibly(jt); 1020 jt->set_class_to_be_initialized(NULL); 1021 } 1022 1023 // Step 3 1024 if (is_being_initialized() && is_reentrant_initialization(jt)) { 1025 DTRACE_CLASSINIT_PROBE_WAIT(recursive, -1, wait); 1026 return; 1027 } 1028 1029 // Step 4 1030 if (is_initialized()) { 1031 DTRACE_CLASSINIT_PROBE_WAIT(concurrent, -1, wait); 1032 return; 1033 } 1034 1035 // Step 5 1036 if (is_in_error_state()) { 1037 DTRACE_CLASSINIT_PROBE_WAIT(erroneous, -1, wait); 1038 ResourceMark rm(THREAD); 1039 const char* desc = "Could not initialize class "; 1040 const char* className = external_name(); 1041 size_t msglen = strlen(desc) + strlen(className) + 1; 1042 char* message = NEW_RESOURCE_ARRAY(char, msglen); 1043 if (NULL == message) { 1044 // Out of memory: can't create detailed error message 1045 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), className); 1046 } else { 1047 jio_snprintf(message, msglen, "%s%s", desc, className); 1048 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), message); 1049 } 1050 } 1051 1052 // Step 6 1053 set_init_state(being_initialized); 1054 set_init_thread(jt); 1055 } 1056 1057 // Step 7 1058 // Next, if C is a class rather than an interface, initialize it's super class and super 1059 // interfaces. 1060 if (!is_interface()) { 1061 Klass* super_klass = super(); 1062 if (super_klass != NULL && super_klass->should_be_initialized()) { 1063 super_klass->initialize(THREAD); 1064 } 1065 // If C implements any interface that declares a non-static, concrete method, 1066 // the initialization of C triggers initialization of its super interfaces. 1067 // Only need to recurse if has_nonstatic_concrete_methods which includes declaring and 1068 // having a superinterface that declares, non-static, concrete methods 1069 if (!HAS_PENDING_EXCEPTION && has_nonstatic_concrete_methods()) { 1070 initialize_super_interfaces(THREAD); 1071 } 1072 1073 // If any exceptions, complete abruptly, throwing the same exception as above. 1074 if (HAS_PENDING_EXCEPTION) { 1075 Handle e(THREAD, PENDING_EXCEPTION); 1076 CLEAR_PENDING_EXCEPTION; 1077 { 1078 EXCEPTION_MARK; 1079 // Locks object, set state, and notify all waiting threads 1080 set_initialization_state_and_notify(initialization_error, THREAD); 1081 CLEAR_PENDING_EXCEPTION; 1082 } 1083 DTRACE_CLASSINIT_PROBE_WAIT(super__failed, -1, wait); 1084 THROW_OOP(e()); 1085 } 1086 } 1087 1088 1089 // Look for aot compiled methods for this klass, including class initializer. 1090 AOTLoader::load_for_klass(this, THREAD); 1091 1092 // Step 8 1093 { 1094 DTRACE_CLASSINIT_PROBE_WAIT(clinit, -1, wait); 1095 // Timer includes any side effects of class initialization (resolution, 1096 // etc), but not recursive entry into call_class_initializer(). 1097 PerfClassTraceTime timer(ClassLoader::perf_class_init_time(), 1098 ClassLoader::perf_class_init_selftime(), 1099 ClassLoader::perf_classes_inited(), 1100 jt->get_thread_stat()->perf_recursion_counts_addr(), 1101 jt->get_thread_stat()->perf_timers_addr(), 1102 PerfClassTraceTime::CLASS_CLINIT); 1103 call_class_initializer(THREAD); 1104 } 1105 1106 // Step 9 1107 if (!HAS_PENDING_EXCEPTION) { 1108 set_initialization_state_and_notify(fully_initialized, CHECK); 1109 { 1110 debug_only(vtable().verify(tty, true);) 1111 } 1112 } 1113 else { 1114 // Step 10 and 11 1115 Handle e(THREAD, PENDING_EXCEPTION); 1116 CLEAR_PENDING_EXCEPTION; 1117 // JVMTI has already reported the pending exception 1118 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError 1119 JvmtiExport::clear_detected_exception(jt); 1120 { 1121 EXCEPTION_MARK; 1122 set_initialization_state_and_notify(initialization_error, THREAD); 1123 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, class initialization error is thrown below 1124 // JVMTI has already reported the pending exception 1125 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError 1126 JvmtiExport::clear_detected_exception(jt); 1127 } 1128 DTRACE_CLASSINIT_PROBE_WAIT(error, -1, wait); 1129 if (e->is_a(SystemDictionary::Error_klass())) { 1130 THROW_OOP(e()); 1131 } else { 1132 JavaCallArguments args(e); 1133 THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(), 1134 vmSymbols::throwable_void_signature(), 1135 &args); 1136 } 1137 } 1138 DTRACE_CLASSINIT_PROBE_WAIT(end, -1, wait); 1139 } 1140 1141 1142 void InstanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) { 1143 Handle h_init_lock(THREAD, init_lock()); 1144 if (h_init_lock() != NULL) { 1145 ObjectLocker ol(h_init_lock, THREAD); 1146 set_init_thread(NULL); // reset _init_thread before changing _init_state 1147 set_init_state(state); 1148 fence_and_clear_init_lock(); 1149 ol.notify_all(CHECK); 1150 } else { 1151 assert(h_init_lock() != NULL, "The initialization state should never be set twice"); 1152 set_init_thread(NULL); // reset _init_thread before changing _init_state 1153 set_init_state(state); 1154 } 1155 } 1156 1157 Klass* InstanceKlass::implementor() const { 1158 Klass* volatile* k = adr_implementor(); 1159 if (k == NULL) { 1160 return NULL; 1161 } else { 1162 // This load races with inserts, and therefore needs acquire. 1163 Klass* kls = Atomic::load_acquire(k); 1164 if (kls != NULL && !kls->is_loader_alive()) { 1165 return NULL; // don't return unloaded class 1166 } else { 1167 return kls; 1168 } 1169 } 1170 } 1171 1172 1173 void InstanceKlass::set_implementor(Klass* k) { 1174 assert_locked_or_safepoint(Compile_lock); 1175 assert(is_interface(), "not interface"); 1176 Klass* volatile* addr = adr_implementor(); 1177 assert(addr != NULL, "null addr"); 1178 if (addr != NULL) { 1179 Atomic::release_store(addr, k); 1180 } 1181 } 1182 1183 int InstanceKlass::nof_implementors() const { 1184 Klass* k = implementor(); 1185 if (k == NULL) { 1186 return 0; 1187 } else if (k != this) { 1188 return 1; 1189 } else { 1190 return 2; 1191 } 1192 } 1193 1194 // The embedded _implementor field can only record one implementor. 1195 // When there are more than one implementors, the _implementor field 1196 // is set to the interface Klass* itself. Following are the possible 1197 // values for the _implementor field: 1198 // NULL - no implementor 1199 // implementor Klass* - one implementor 1200 // self - more than one implementor 1201 // 1202 // The _implementor field only exists for interfaces. 1203 void InstanceKlass::add_implementor(Klass* k) { 1204 if (Universe::is_fully_initialized()) { 1205 assert_lock_strong(Compile_lock); 1206 } 1207 assert(is_interface(), "not interface"); 1208 // Filter out my subinterfaces. 1209 // (Note: Interfaces are never on the subklass list.) 1210 if (InstanceKlass::cast(k)->is_interface()) return; 1211 1212 // Filter out subclasses whose supers already implement me. 1213 // (Note: CHA must walk subclasses of direct implementors 1214 // in order to locate indirect implementors.) 1215 Klass* sk = k->super(); 1216 if (sk != NULL && InstanceKlass::cast(sk)->implements_interface(this)) 1217 // We only need to check one immediate superclass, since the 1218 // implements_interface query looks at transitive_interfaces. 1219 // Any supers of the super have the same (or fewer) transitive_interfaces. 1220 return; 1221 1222 Klass* ik = implementor(); 1223 if (ik == NULL) { 1224 set_implementor(k); 1225 } else if (ik != this && ik != k) { 1226 // There is already an implementor. Use itself as an indicator of 1227 // more than one implementors. 1228 set_implementor(this); 1229 } 1230 1231 // The implementor also implements the transitive_interfaces 1232 for (int index = 0; index < local_interfaces()->length(); index++) { 1233 InstanceKlass::cast(local_interfaces()->at(index))->add_implementor(k); 1234 } 1235 } 1236 1237 void InstanceKlass::init_implementor() { 1238 if (is_interface()) { 1239 set_implementor(NULL); 1240 } 1241 } 1242 1243 1244 void InstanceKlass::process_interfaces(Thread *thread) { 1245 // link this class into the implementors list of every interface it implements 1246 for (int i = local_interfaces()->length() - 1; i >= 0; i--) { 1247 assert(local_interfaces()->at(i)->is_klass(), "must be a klass"); 1248 InstanceKlass* interf = InstanceKlass::cast(local_interfaces()->at(i)); 1249 assert(interf->is_interface(), "expected interface"); 1250 interf->add_implementor(this); 1251 } 1252 } 1253 1254 bool InstanceKlass::can_be_primary_super_slow() const { 1255 if (is_interface()) 1256 return false; 1257 else 1258 return Klass::can_be_primary_super_slow(); 1259 } 1260 1261 GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots, 1262 Array<InstanceKlass*>* transitive_interfaces) { 1263 // The secondaries are the implemented interfaces. 1264 Array<InstanceKlass*>* interfaces = transitive_interfaces; 1265 int num_secondaries = num_extra_slots + interfaces->length(); 1266 if (num_secondaries == 0) { 1267 // Must share this for correct bootstrapping! 1268 set_secondary_supers(Universe::the_empty_klass_array()); 1269 return NULL; 1270 } else if (num_extra_slots == 0) { 1271 // The secondary super list is exactly the same as the transitive interfaces, so 1272 // let's use it instead of making a copy. 1273 // Redefine classes has to be careful not to delete this! 1274 // We need the cast because Array<Klass*> is NOT a supertype of Array<InstanceKlass*>, 1275 // (but it's safe to do here because we won't write into _secondary_supers from this point on). 1276 set_secondary_supers((Array<Klass*>*)(address)interfaces); 1277 return NULL; 1278 } else { 1279 // Copy transitive interfaces to a temporary growable array to be constructed 1280 // into the secondary super list with extra slots. 1281 GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length()); 1282 for (int i = 0; i < interfaces->length(); i++) { 1283 secondaries->push(interfaces->at(i)); 1284 } 1285 return secondaries; 1286 } 1287 } 1288 1289 bool InstanceKlass::implements_interface(Klass* k) const { 1290 if (this == k) return true; 1291 assert(k->is_interface(), "should be an interface class"); 1292 for (int i = 0; i < transitive_interfaces()->length(); i++) { 1293 if (transitive_interfaces()->at(i) == k) { 1294 return true; 1295 } 1296 } 1297 return false; 1298 } 1299 1300 bool InstanceKlass::is_same_or_direct_interface(Klass *k) const { 1301 // Verify direct super interface 1302 if (this == k) return true; 1303 assert(k->is_interface(), "should be an interface class"); 1304 for (int i = 0; i < local_interfaces()->length(); i++) { 1305 if (local_interfaces()->at(i) == k) { 1306 return true; 1307 } 1308 } 1309 return false; 1310 } 1311 1312 objArrayOop InstanceKlass::allocate_objArray(int n, int length, TRAPS) { 1313 check_array_allocation_length(length, arrayOopDesc::max_array_length(T_OBJECT), CHECK_NULL); 1314 int size = objArrayOopDesc::object_size(length); 1315 Klass* ak = array_klass(n, CHECK_NULL); 1316 objArrayOop o = (objArrayOop)Universe::heap()->array_allocate(ak, size, length, 1317 /* do_zero */ true, CHECK_NULL); 1318 return o; 1319 } 1320 1321 instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) { 1322 if (TraceFinalizerRegistration) { 1323 tty->print("Registered "); 1324 i->print_value_on(tty); 1325 tty->print_cr(" (" INTPTR_FORMAT ") as finalizable", p2i(i)); 1326 } 1327 instanceHandle h_i(THREAD, i); 1328 // Pass the handle as argument, JavaCalls::call expects oop as jobjects 1329 JavaValue result(T_VOID); 1330 JavaCallArguments args(h_i); 1331 methodHandle mh (THREAD, Universe::finalizer_register_method()); 1332 JavaCalls::call(&result, mh, &args, CHECK_NULL); 1333 return h_i(); 1334 } 1335 1336 instanceOop InstanceKlass::allocate_instance(TRAPS) { 1337 bool has_finalizer_flag = has_finalizer(); // Query before possible GC 1338 int size = size_helper(); // Query before forming handle. 1339 1340 instanceOop i; 1341 1342 i = (instanceOop)Universe::heap()->obj_allocate(this, size, CHECK_NULL); 1343 if (has_finalizer_flag && !RegisterFinalizersAtInit) { 1344 i = register_finalizer(i, CHECK_NULL); 1345 } 1346 return i; 1347 } 1348 1349 instanceHandle InstanceKlass::allocate_instance_handle(TRAPS) { 1350 return instanceHandle(THREAD, allocate_instance(THREAD)); 1351 } 1352 1353 void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) { 1354 if (is_interface() || is_abstract()) { 1355 ResourceMark rm(THREAD); 1356 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError() 1357 : vmSymbols::java_lang_InstantiationException(), external_name()); 1358 } 1359 if (this == SystemDictionary::Class_klass()) { 1360 ResourceMark rm(THREAD); 1361 THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError() 1362 : vmSymbols::java_lang_IllegalAccessException(), external_name()); 1363 } 1364 } 1365 1366 Klass* InstanceKlass::array_klass_impl(bool or_null, int n, TRAPS) { 1367 // Need load-acquire for lock-free read 1368 if (array_klasses_acquire() == NULL) { 1369 if (or_null) return NULL; 1370 1371 ResourceMark rm(THREAD); 1372 JavaThread *jt = (JavaThread *)THREAD; 1373 { 1374 // Atomic creation of array_klasses 1375 MutexLocker ma(THREAD, MultiArray_lock); 1376 1377 // Check if update has already taken place 1378 if (array_klasses() == NULL) { 1379 ObjArrayKlass* k = ObjArrayKlass::allocate_objArray_klass(class_loader_data(), 1, this, CHECK_NULL); 1380 // use 'release' to pair with lock-free load 1381 release_set_array_klasses(k); 1382 } 1383 } 1384 } 1385 // _this will always be set at this point 1386 ObjArrayKlass* oak = array_klasses(); 1387 if (or_null) { 1388 return oak->array_klass_or_null(n); 1389 } 1390 return oak->array_klass(n, THREAD); 1391 } 1392 1393 Klass* InstanceKlass::array_klass_impl(bool or_null, TRAPS) { 1394 return array_klass_impl(or_null, 1, THREAD); 1395 } 1396 1397 static int call_class_initializer_counter = 0; // for debugging 1398 1399 Method* InstanceKlass::class_initializer() const { 1400 Method* clinit = find_method( 1401 vmSymbols::class_initializer_name(), vmSymbols::void_method_signature()); 1402 if (clinit != NULL && clinit->has_valid_initializer_flags()) { 1403 return clinit; 1404 } 1405 return NULL; 1406 } 1407 1408 void InstanceKlass::call_class_initializer(TRAPS) { 1409 if (ReplayCompiles && 1410 (ReplaySuppressInitializers == 1 || 1411 (ReplaySuppressInitializers >= 2 && class_loader() != NULL))) { 1412 // Hide the existence of the initializer for the purpose of replaying the compile 1413 return; 1414 } 1415 1416 methodHandle h_method(THREAD, class_initializer()); 1417 assert(!is_initialized(), "we cannot initialize twice"); 1418 LogTarget(Info, class, init) lt; 1419 if (lt.is_enabled()) { 1420 ResourceMark rm(THREAD); 1421 LogStream ls(lt); 1422 ls.print("%d Initializing ", call_class_initializer_counter++); 1423 name()->print_value_on(&ls); 1424 ls.print_cr("%s (" INTPTR_FORMAT ")", h_method() == NULL ? "(no method)" : "", p2i(this)); 1425 } 1426 if (h_method() != NULL) { 1427 JavaCallArguments args; // No arguments 1428 JavaValue result(T_VOID); 1429 JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args) 1430 } 1431 } 1432 1433 1434 void InstanceKlass::mask_for(const methodHandle& method, int bci, 1435 InterpreterOopMap* entry_for) { 1436 // Lazily create the _oop_map_cache at first request 1437 // Lock-free access requires load_acquire. 1438 OopMapCache* oop_map_cache = Atomic::load_acquire(&_oop_map_cache); 1439 if (oop_map_cache == NULL) { 1440 MutexLocker x(OopMapCacheAlloc_lock); 1441 // Check if _oop_map_cache was allocated while we were waiting for this lock 1442 if ((oop_map_cache = _oop_map_cache) == NULL) { 1443 oop_map_cache = new OopMapCache(); 1444 // Ensure _oop_map_cache is stable, since it is examined without a lock 1445 Atomic::release_store(&_oop_map_cache, oop_map_cache); 1446 } 1447 } 1448 // _oop_map_cache is constant after init; lookup below does its own locking. 1449 oop_map_cache->lookup(method, bci, entry_for); 1450 } 1451 1452 bool InstanceKlass::contains_field_offset(int offset) { 1453 fieldDescriptor fd; 1454 return find_field_from_offset(offset, false, &fd); 1455 } 1456 1457 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const { 1458 for (JavaFieldStream fs(this); !fs.done(); fs.next()) { 1459 Symbol* f_name = fs.name(); 1460 Symbol* f_sig = fs.signature(); 1461 if (f_name == name && f_sig == sig) { 1462 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index()); 1463 return true; 1464 } 1465 } 1466 return false; 1467 } 1468 1469 1470 Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const { 1471 const int n = local_interfaces()->length(); 1472 for (int i = 0; i < n; i++) { 1473 Klass* intf1 = local_interfaces()->at(i); 1474 assert(intf1->is_interface(), "just checking type"); 1475 // search for field in current interface 1476 if (InstanceKlass::cast(intf1)->find_local_field(name, sig, fd)) { 1477 assert(fd->is_static(), "interface field must be static"); 1478 return intf1; 1479 } 1480 // search for field in direct superinterfaces 1481 Klass* intf2 = InstanceKlass::cast(intf1)->find_interface_field(name, sig, fd); 1482 if (intf2 != NULL) return intf2; 1483 } 1484 // otherwise field lookup fails 1485 return NULL; 1486 } 1487 1488 1489 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const { 1490 // search order according to newest JVM spec (5.4.3.2, p.167). 1491 // 1) search for field in current klass 1492 if (find_local_field(name, sig, fd)) { 1493 return const_cast<InstanceKlass*>(this); 1494 } 1495 // 2) search for field recursively in direct superinterfaces 1496 { Klass* intf = find_interface_field(name, sig, fd); 1497 if (intf != NULL) return intf; 1498 } 1499 // 3) apply field lookup recursively if superclass exists 1500 { Klass* supr = super(); 1501 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, fd); 1502 } 1503 // 4) otherwise field lookup fails 1504 return NULL; 1505 } 1506 1507 1508 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const { 1509 // search order according to newest JVM spec (5.4.3.2, p.167). 1510 // 1) search for field in current klass 1511 if (find_local_field(name, sig, fd)) { 1512 if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this); 1513 } 1514 // 2) search for field recursively in direct superinterfaces 1515 if (is_static) { 1516 Klass* intf = find_interface_field(name, sig, fd); 1517 if (intf != NULL) return intf; 1518 } 1519 // 3) apply field lookup recursively if superclass exists 1520 { Klass* supr = super(); 1521 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, is_static, fd); 1522 } 1523 // 4) otherwise field lookup fails 1524 return NULL; 1525 } 1526 1527 1528 bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const { 1529 for (JavaFieldStream fs(this); !fs.done(); fs.next()) { 1530 if (fs.offset() == offset) { 1531 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index()); 1532 if (fd->is_static() == is_static) return true; 1533 } 1534 } 1535 return false; 1536 } 1537 1538 1539 bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const { 1540 Klass* klass = const_cast<InstanceKlass*>(this); 1541 while (klass != NULL) { 1542 if (InstanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) { 1543 return true; 1544 } 1545 klass = klass->super(); 1546 } 1547 return false; 1548 } 1549 1550 1551 void InstanceKlass::methods_do(void f(Method* method)) { 1552 // Methods aren't stable until they are loaded. This can be read outside 1553 // a lock through the ClassLoaderData for profiling 1554 if (!is_loaded()) { 1555 return; 1556 } 1557 1558 int len = methods()->length(); 1559 for (int index = 0; index < len; index++) { 1560 Method* m = methods()->at(index); 1561 assert(m->is_method(), "must be method"); 1562 f(m); 1563 } 1564 } 1565 1566 1567 void InstanceKlass::do_local_static_fields(FieldClosure* cl) { 1568 for (JavaFieldStream fs(this); !fs.done(); fs.next()) { 1569 if (fs.access_flags().is_static()) { 1570 fieldDescriptor& fd = fs.field_descriptor(); 1571 cl->do_field(&fd); 1572 } 1573 } 1574 } 1575 1576 1577 void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle mirror, TRAPS) { 1578 for (JavaFieldStream fs(this); !fs.done(); fs.next()) { 1579 if (fs.access_flags().is_static()) { 1580 fieldDescriptor& fd = fs.field_descriptor(); 1581 f(&fd, mirror, CHECK); 1582 } 1583 } 1584 } 1585 1586 1587 static int compare_fields_by_offset(int* a, int* b) { 1588 return a[0] - b[0]; 1589 } 1590 1591 void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) { 1592 InstanceKlass* super = superklass(); 1593 if (super != NULL) { 1594 super->do_nonstatic_fields(cl); 1595 } 1596 fieldDescriptor fd; 1597 int length = java_fields_count(); 1598 // In DebugInfo nonstatic fields are sorted by offset. 1599 int* fields_sorted = NEW_C_HEAP_ARRAY(int, 2*(length+1), mtClass); 1600 int j = 0; 1601 for (int i = 0; i < length; i += 1) { 1602 fd.reinitialize(this, i); 1603 if (!fd.is_static()) { 1604 fields_sorted[j + 0] = fd.offset(); 1605 fields_sorted[j + 1] = i; 1606 j += 2; 1607 } 1608 } 1609 if (j > 0) { 1610 length = j; 1611 // _sort_Fn is defined in growableArray.hpp. 1612 qsort(fields_sorted, length/2, 2*sizeof(int), (_sort_Fn)compare_fields_by_offset); 1613 for (int i = 0; i < length; i += 2) { 1614 fd.reinitialize(this, fields_sorted[i + 1]); 1615 assert(!fd.is_static() && fd.offset() == fields_sorted[i], "only nonstatic fields"); 1616 cl->do_field(&fd); 1617 } 1618 } 1619 FREE_C_HEAP_ARRAY(int, fields_sorted); 1620 } 1621 1622 1623 void InstanceKlass::array_klasses_do(void f(Klass* k, TRAPS), TRAPS) { 1624 if (array_klasses() != NULL) 1625 array_klasses()->array_klasses_do(f, THREAD); 1626 } 1627 1628 void InstanceKlass::array_klasses_do(void f(Klass* k)) { 1629 if (array_klasses() != NULL) 1630 array_klasses()->array_klasses_do(f); 1631 } 1632 1633 #ifdef ASSERT 1634 static int linear_search(const Array<Method*>* methods, 1635 const Symbol* name, 1636 const Symbol* signature) { 1637 const int len = methods->length(); 1638 for (int index = 0; index < len; index++) { 1639 const Method* const m = methods->at(index); 1640 assert(m->is_method(), "must be method"); 1641 if (m->signature() == signature && m->name() == name) { 1642 return index; 1643 } 1644 } 1645 return -1; 1646 } 1647 #endif 1648 1649 bool InstanceKlass::_disable_method_binary_search = false; 1650 1651 NOINLINE int linear_search(const Array<Method*>* methods, const Symbol* name) { 1652 int len = methods->length(); 1653 int l = 0; 1654 int h = len - 1; 1655 while (l <= h) { 1656 Method* m = methods->at(l); 1657 if (m->name() == name) { 1658 return l; 1659 } 1660 l++; 1661 } 1662 return -1; 1663 } 1664 1665 inline int InstanceKlass::quick_search(const Array<Method*>* methods, const Symbol* name) { 1666 if (_disable_method_binary_search) { 1667 assert(DynamicDumpSharedSpaces, "must be"); 1668 // At the final stage of dynamic dumping, the methods array may not be sorted 1669 // by ascending addresses of their names, so we can't use binary search anymore. 1670 // However, methods with the same name are still laid out consecutively inside the 1671 // methods array, so let's look for the first one that matches. 1672 return linear_search(methods, name); 1673 } 1674 1675 int len = methods->length(); 1676 int l = 0; 1677 int h = len - 1; 1678 1679 // methods are sorted by ascending addresses of their names, so do binary search 1680 while (l <= h) { 1681 int mid = (l + h) >> 1; 1682 Method* m = methods->at(mid); 1683 assert(m->is_method(), "must be method"); 1684 int res = m->name()->fast_compare(name); 1685 if (res == 0) { 1686 return mid; 1687 } else if (res < 0) { 1688 l = mid + 1; 1689 } else { 1690 h = mid - 1; 1691 } 1692 } 1693 return -1; 1694 } 1695 1696 // find_method looks up the name/signature in the local methods array 1697 Method* InstanceKlass::find_method(const Symbol* name, 1698 const Symbol* signature) const { 1699 return find_method_impl(name, signature, find_overpass, find_static, find_private); 1700 } 1701 1702 Method* InstanceKlass::find_method_impl(const Symbol* name, 1703 const Symbol* signature, 1704 OverpassLookupMode overpass_mode, 1705 StaticLookupMode static_mode, 1706 PrivateLookupMode private_mode) const { 1707 return InstanceKlass::find_method_impl(methods(), 1708 name, 1709 signature, 1710 overpass_mode, 1711 static_mode, 1712 private_mode); 1713 } 1714 1715 // find_instance_method looks up the name/signature in the local methods array 1716 // and skips over static methods 1717 Method* InstanceKlass::find_instance_method(const Array<Method*>* methods, 1718 const Symbol* name, 1719 const Symbol* signature, 1720 PrivateLookupMode private_mode) { 1721 Method* const meth = InstanceKlass::find_method_impl(methods, 1722 name, 1723 signature, 1724 find_overpass, 1725 skip_static, 1726 private_mode); 1727 assert(((meth == NULL) || !meth->is_static()), 1728 "find_instance_method should have skipped statics"); 1729 return meth; 1730 } 1731 1732 // find_instance_method looks up the name/signature in the local methods array 1733 // and skips over static methods 1734 Method* InstanceKlass::find_instance_method(const Symbol* name, 1735 const Symbol* signature, 1736 PrivateLookupMode private_mode) const { 1737 return InstanceKlass::find_instance_method(methods(), name, signature, private_mode); 1738 } 1739 1740 // Find looks up the name/signature in the local methods array 1741 // and filters on the overpass, static and private flags 1742 // This returns the first one found 1743 // note that the local methods array can have up to one overpass, one static 1744 // and one instance (private or not) with the same name/signature 1745 Method* InstanceKlass::find_local_method(const Symbol* name, 1746 const Symbol* signature, 1747 OverpassLookupMode overpass_mode, 1748 StaticLookupMode static_mode, 1749 PrivateLookupMode private_mode) const { 1750 return InstanceKlass::find_method_impl(methods(), 1751 name, 1752 signature, 1753 overpass_mode, 1754 static_mode, 1755 private_mode); 1756 } 1757 1758 // Find looks up the name/signature in the local methods array 1759 // and filters on the overpass, static and private flags 1760 // This returns the first one found 1761 // note that the local methods array can have up to one overpass, one static 1762 // and one instance (private or not) with the same name/signature 1763 Method* InstanceKlass::find_local_method(const Array<Method*>* methods, 1764 const Symbol* name, 1765 const Symbol* signature, 1766 OverpassLookupMode overpass_mode, 1767 StaticLookupMode static_mode, 1768 PrivateLookupMode private_mode) { 1769 return InstanceKlass::find_method_impl(methods, 1770 name, 1771 signature, 1772 overpass_mode, 1773 static_mode, 1774 private_mode); 1775 } 1776 1777 Method* InstanceKlass::find_method(const Array<Method*>* methods, 1778 const Symbol* name, 1779 const Symbol* signature) { 1780 return InstanceKlass::find_method_impl(methods, 1781 name, 1782 signature, 1783 find_overpass, 1784 find_static, 1785 find_private); 1786 } 1787 1788 Method* InstanceKlass::find_method_impl(const Array<Method*>* methods, 1789 const Symbol* name, 1790 const Symbol* signature, 1791 OverpassLookupMode overpass_mode, 1792 StaticLookupMode static_mode, 1793 PrivateLookupMode private_mode) { 1794 int hit = find_method_index(methods, name, signature, overpass_mode, static_mode, private_mode); 1795 return hit >= 0 ? methods->at(hit): NULL; 1796 } 1797 1798 // true if method matches signature and conforms to skipping_X conditions. 1799 static bool method_matches(const Method* m, 1800 const Symbol* signature, 1801 bool skipping_overpass, 1802 bool skipping_static, 1803 bool skipping_private) { 1804 return ((m->signature() == signature) && 1805 (!skipping_overpass || !m->is_overpass()) && 1806 (!skipping_static || !m->is_static()) && 1807 (!skipping_private || !m->is_private())); 1808 } 1809 1810 // Used directly for default_methods to find the index into the 1811 // default_vtable_indices, and indirectly by find_method 1812 // find_method_index looks in the local methods array to return the index 1813 // of the matching name/signature. If, overpass methods are being ignored, 1814 // the search continues to find a potential non-overpass match. This capability 1815 // is important during method resolution to prefer a static method, for example, 1816 // over an overpass method. 1817 // There is the possibility in any _method's array to have the same name/signature 1818 // for a static method, an overpass method and a local instance method 1819 // To correctly catch a given method, the search criteria may need 1820 // to explicitly skip the other two. For local instance methods, it 1821 // is often necessary to skip private methods 1822 int InstanceKlass::find_method_index(const Array<Method*>* methods, 1823 const Symbol* name, 1824 const Symbol* signature, 1825 OverpassLookupMode overpass_mode, 1826 StaticLookupMode static_mode, 1827 PrivateLookupMode private_mode) { 1828 const bool skipping_overpass = (overpass_mode == skip_overpass); 1829 const bool skipping_static = (static_mode == skip_static); 1830 const bool skipping_private = (private_mode == skip_private); 1831 const int hit = quick_search(methods, name); 1832 if (hit != -1) { 1833 const Method* const m = methods->at(hit); 1834 1835 // Do linear search to find matching signature. First, quick check 1836 // for common case, ignoring overpasses if requested. 1837 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) { 1838 return hit; 1839 } 1840 1841 // search downwards through overloaded methods 1842 int i; 1843 for (i = hit - 1; i >= 0; --i) { 1844 const Method* const m = methods->at(i); 1845 assert(m->is_method(), "must be method"); 1846 if (m->name() != name) { 1847 break; 1848 } 1849 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) { 1850 return i; 1851 } 1852 } 1853 // search upwards 1854 for (i = hit + 1; i < methods->length(); ++i) { 1855 const Method* const m = methods->at(i); 1856 assert(m->is_method(), "must be method"); 1857 if (m->name() != name) { 1858 break; 1859 } 1860 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) { 1861 return i; 1862 } 1863 } 1864 // not found 1865 #ifdef ASSERT 1866 const int index = (skipping_overpass || skipping_static || skipping_private) ? -1 : 1867 linear_search(methods, name, signature); 1868 assert(-1 == index, "binary search should have found entry %d", index); 1869 #endif 1870 } 1871 return -1; 1872 } 1873 1874 int InstanceKlass::find_method_by_name(const Symbol* name, int* end) const { 1875 return find_method_by_name(methods(), name, end); 1876 } 1877 1878 int InstanceKlass::find_method_by_name(const Array<Method*>* methods, 1879 const Symbol* name, 1880 int* end_ptr) { 1881 assert(end_ptr != NULL, "just checking"); 1882 int start = quick_search(methods, name); 1883 int end = start + 1; 1884 if (start != -1) { 1885 while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start; 1886 while (end < methods->length() && (methods->at(end))->name() == name) ++end; 1887 *end_ptr = end; 1888 return start; 1889 } 1890 return -1; 1891 } 1892 1893 // uncached_lookup_method searches both the local class methods array and all 1894 // superclasses methods arrays, skipping any overpass methods in superclasses, 1895 // and possibly skipping private methods. 1896 Method* InstanceKlass::uncached_lookup_method(const Symbol* name, 1897 const Symbol* signature, 1898 OverpassLookupMode overpass_mode, 1899 PrivateLookupMode private_mode) const { 1900 OverpassLookupMode overpass_local_mode = overpass_mode; 1901 const Klass* klass = this; 1902 while (klass != NULL) { 1903 Method* const method = InstanceKlass::cast(klass)->find_method_impl(name, 1904 signature, 1905 overpass_local_mode, 1906 find_static, 1907 private_mode); 1908 if (method != NULL) { 1909 return method; 1910 } 1911 klass = klass->super(); 1912 overpass_local_mode = skip_overpass; // Always ignore overpass methods in superclasses 1913 } 1914 return NULL; 1915 } 1916 1917 #ifdef ASSERT 1918 // search through class hierarchy and return true if this class or 1919 // one of the superclasses was redefined 1920 bool InstanceKlass::has_redefined_this_or_super() const { 1921 const Klass* klass = this; 1922 while (klass != NULL) { 1923 if (InstanceKlass::cast(klass)->has_been_redefined()) { 1924 return true; 1925 } 1926 klass = klass->super(); 1927 } 1928 return false; 1929 } 1930 #endif 1931 1932 // lookup a method in the default methods list then in all transitive interfaces 1933 // Do NOT return private or static methods 1934 Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name, 1935 Symbol* signature) const { 1936 Method* m = NULL; 1937 if (default_methods() != NULL) { 1938 m = find_method(default_methods(), name, signature); 1939 } 1940 // Look up interfaces 1941 if (m == NULL) { 1942 m = lookup_method_in_all_interfaces(name, signature, find_defaults); 1943 } 1944 return m; 1945 } 1946 1947 // lookup a method in all the interfaces that this class implements 1948 // Do NOT return private or static methods, new in JDK8 which are not externally visible 1949 // They should only be found in the initial InterfaceMethodRef 1950 Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name, 1951 Symbol* signature, 1952 DefaultsLookupMode defaults_mode) const { 1953 Array<InstanceKlass*>* all_ifs = transitive_interfaces(); 1954 int num_ifs = all_ifs->length(); 1955 InstanceKlass *ik = NULL; 1956 for (int i = 0; i < num_ifs; i++) { 1957 ik = all_ifs->at(i); 1958 Method* m = ik->lookup_method(name, signature); 1959 if (m != NULL && m->is_public() && !m->is_static() && 1960 ((defaults_mode != skip_defaults) || !m->is_default_method())) { 1961 return m; 1962 } 1963 } 1964 return NULL; 1965 } 1966 1967 /* jni_id_for_impl for jfieldIds only */ 1968 JNIid* InstanceKlass::jni_id_for_impl(int offset) { 1969 MutexLocker ml(JfieldIdCreation_lock); 1970 // Retry lookup after we got the lock 1971 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset); 1972 if (probe == NULL) { 1973 // Slow case, allocate new static field identifier 1974 probe = new JNIid(this, offset, jni_ids()); 1975 set_jni_ids(probe); 1976 } 1977 return probe; 1978 } 1979 1980 1981 /* jni_id_for for jfieldIds only */ 1982 JNIid* InstanceKlass::jni_id_for(int offset) { 1983 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset); 1984 if (probe == NULL) { 1985 probe = jni_id_for_impl(offset); 1986 } 1987 return probe; 1988 } 1989 1990 u2 InstanceKlass::enclosing_method_data(int offset) const { 1991 const Array<jushort>* const inner_class_list = inner_classes(); 1992 if (inner_class_list == NULL) { 1993 return 0; 1994 } 1995 const int length = inner_class_list->length(); 1996 if (length % inner_class_next_offset == 0) { 1997 return 0; 1998 } 1999 const int index = length - enclosing_method_attribute_size; 2000 assert(offset < enclosing_method_attribute_size, "invalid offset"); 2001 return inner_class_list->at(index + offset); 2002 } 2003 2004 void InstanceKlass::set_enclosing_method_indices(u2 class_index, 2005 u2 method_index) { 2006 Array<jushort>* inner_class_list = inner_classes(); 2007 assert (inner_class_list != NULL, "_inner_classes list is not set up"); 2008 int length = inner_class_list->length(); 2009 if (length % inner_class_next_offset == enclosing_method_attribute_size) { 2010 int index = length - enclosing_method_attribute_size; 2011 inner_class_list->at_put( 2012 index + enclosing_method_class_index_offset, class_index); 2013 inner_class_list->at_put( 2014 index + enclosing_method_method_index_offset, method_index); 2015 } 2016 } 2017 2018 // Lookup or create a jmethodID. 2019 // This code is called by the VMThread and JavaThreads so the 2020 // locking has to be done very carefully to avoid deadlocks 2021 // and/or other cache consistency problems. 2022 // 2023 jmethodID InstanceKlass::get_jmethod_id(const methodHandle& method_h) { 2024 size_t idnum = (size_t)method_h->method_idnum(); 2025 jmethodID* jmeths = methods_jmethod_ids_acquire(); 2026 size_t length = 0; 2027 jmethodID id = NULL; 2028 2029 // We use a double-check locking idiom here because this cache is 2030 // performance sensitive. In the normal system, this cache only 2031 // transitions from NULL to non-NULL which is safe because we use 2032 // release_set_methods_jmethod_ids() to advertise the new cache. 2033 // A partially constructed cache should never be seen by a racing 2034 // thread. We also use release_store() to save a new jmethodID 2035 // in the cache so a partially constructed jmethodID should never be 2036 // seen either. Cache reads of existing jmethodIDs proceed without a 2037 // lock, but cache writes of a new jmethodID requires uniqueness and 2038 // creation of the cache itself requires no leaks so a lock is 2039 // generally acquired in those two cases. 2040 // 2041 // If the RedefineClasses() API has been used, then this cache can 2042 // grow and we'll have transitions from non-NULL to bigger non-NULL. 2043 // Cache creation requires no leaks and we require safety between all 2044 // cache accesses and freeing of the old cache so a lock is generally 2045 // acquired when the RedefineClasses() API has been used. 2046 2047 if (jmeths != NULL) { 2048 // the cache already exists 2049 if (!idnum_can_increment()) { 2050 // the cache can't grow so we can just get the current values 2051 get_jmethod_id_length_value(jmeths, idnum, &length, &id); 2052 } else { 2053 // cache can grow so we have to be more careful 2054 if (Threads::number_of_threads() == 0 || 2055 SafepointSynchronize::is_at_safepoint()) { 2056 // we're single threaded or at a safepoint - no locking needed 2057 get_jmethod_id_length_value(jmeths, idnum, &length, &id); 2058 } else { 2059 MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag); 2060 get_jmethod_id_length_value(jmeths, idnum, &length, &id); 2061 } 2062 } 2063 } 2064 // implied else: 2065 // we need to allocate a cache so default length and id values are good 2066 2067 if (jmeths == NULL || // no cache yet 2068 length <= idnum || // cache is too short 2069 id == NULL) { // cache doesn't contain entry 2070 2071 // This function can be called by the VMThread so we have to do all 2072 // things that might block on a safepoint before grabbing the lock. 2073 // Otherwise, we can deadlock with the VMThread or have a cache 2074 // consistency issue. These vars keep track of what we might have 2075 // to free after the lock is dropped. 2076 jmethodID to_dealloc_id = NULL; 2077 jmethodID* to_dealloc_jmeths = NULL; 2078 2079 // may not allocate new_jmeths or use it if we allocate it 2080 jmethodID* new_jmeths = NULL; 2081 if (length <= idnum) { 2082 // allocate a new cache that might be used 2083 size_t size = MAX2(idnum+1, (size_t)idnum_allocated_count()); 2084 new_jmeths = NEW_C_HEAP_ARRAY(jmethodID, size+1, mtClass); 2085 memset(new_jmeths, 0, (size+1)*sizeof(jmethodID)); 2086 // cache size is stored in element[0], other elements offset by one 2087 new_jmeths[0] = (jmethodID)size; 2088 } 2089 2090 // allocate a new jmethodID that might be used 2091 jmethodID new_id = NULL; 2092 if (method_h->is_old() && !method_h->is_obsolete()) { 2093 // The method passed in is old (but not obsolete), we need to use the current version 2094 Method* current_method = method_with_idnum((int)idnum); 2095 assert(current_method != NULL, "old and but not obsolete, so should exist"); 2096 new_id = Method::make_jmethod_id(class_loader_data(), current_method); 2097 } else { 2098 // It is the current version of the method or an obsolete method, 2099 // use the version passed in 2100 new_id = Method::make_jmethod_id(class_loader_data(), method_h()); 2101 } 2102 2103 if (Threads::number_of_threads() == 0 || 2104 SafepointSynchronize::is_at_safepoint()) { 2105 // we're single threaded or at a safepoint - no locking needed 2106 id = get_jmethod_id_fetch_or_update(idnum, new_id, new_jmeths, 2107 &to_dealloc_id, &to_dealloc_jmeths); 2108 } else { 2109 MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag); 2110 id = get_jmethod_id_fetch_or_update(idnum, new_id, new_jmeths, 2111 &to_dealloc_id, &to_dealloc_jmeths); 2112 } 2113 2114 // The lock has been dropped so we can free resources. 2115 // Free up either the old cache or the new cache if we allocated one. 2116 if (to_dealloc_jmeths != NULL) { 2117 FreeHeap(to_dealloc_jmeths); 2118 } 2119 // free up the new ID since it wasn't needed 2120 if (to_dealloc_id != NULL) { 2121 Method::destroy_jmethod_id(class_loader_data(), to_dealloc_id); 2122 } 2123 } 2124 return id; 2125 } 2126 2127 // Figure out how many jmethodIDs haven't been allocated, and make 2128 // sure space for them is pre-allocated. This makes getting all 2129 // method ids much, much faster with classes with more than 8 2130 // methods, and has a *substantial* effect on performance with jvmti 2131 // code that loads all jmethodIDs for all classes. 2132 void InstanceKlass::ensure_space_for_methodids(int start_offset) { 2133 int new_jmeths = 0; 2134 int length = methods()->length(); 2135 for (int index = start_offset; index < length; index++) { 2136 Method* m = methods()->at(index); 2137 jmethodID id = m->find_jmethod_id_or_null(); 2138 if (id == NULL) { 2139 new_jmeths++; 2140 } 2141 } 2142 if (new_jmeths != 0) { 2143 Method::ensure_jmethod_ids(class_loader_data(), new_jmeths); 2144 } 2145 } 2146 2147 // Common code to fetch the jmethodID from the cache or update the 2148 // cache with the new jmethodID. This function should never do anything 2149 // that causes the caller to go to a safepoint or we can deadlock with 2150 // the VMThread or have cache consistency issues. 2151 // 2152 jmethodID InstanceKlass::get_jmethod_id_fetch_or_update( 2153 size_t idnum, jmethodID new_id, 2154 jmethodID* new_jmeths, jmethodID* to_dealloc_id_p, 2155 jmethodID** to_dealloc_jmeths_p) { 2156 assert(new_id != NULL, "sanity check"); 2157 assert(to_dealloc_id_p != NULL, "sanity check"); 2158 assert(to_dealloc_jmeths_p != NULL, "sanity check"); 2159 assert(Threads::number_of_threads() == 0 || 2160 SafepointSynchronize::is_at_safepoint() || 2161 JmethodIdCreation_lock->owned_by_self(), "sanity check"); 2162 2163 // reacquire the cache - we are locked, single threaded or at a safepoint 2164 jmethodID* jmeths = methods_jmethod_ids_acquire(); 2165 jmethodID id = NULL; 2166 size_t length = 0; 2167 2168 if (jmeths == NULL || // no cache yet 2169 (length = (size_t)jmeths[0]) <= idnum) { // cache is too short 2170 if (jmeths != NULL) { 2171 // copy any existing entries from the old cache 2172 for (size_t index = 0; index < length; index++) { 2173 new_jmeths[index+1] = jmeths[index+1]; 2174 } 2175 *to_dealloc_jmeths_p = jmeths; // save old cache for later delete 2176 } 2177 release_set_methods_jmethod_ids(jmeths = new_jmeths); 2178 } else { 2179 // fetch jmethodID (if any) from the existing cache 2180 id = jmeths[idnum+1]; 2181 *to_dealloc_jmeths_p = new_jmeths; // save new cache for later delete 2182 } 2183 if (id == NULL) { 2184 // No matching jmethodID in the existing cache or we have a new 2185 // cache or we just grew the cache. This cache write is done here 2186 // by the first thread to win the foot race because a jmethodID 2187 // needs to be unique once it is generally available. 2188 id = new_id; 2189 2190 // The jmethodID cache can be read while unlocked so we have to 2191 // make sure the new jmethodID is complete before installing it 2192 // in the cache. 2193 Atomic::release_store(&jmeths[idnum+1], id); 2194 } else { 2195 *to_dealloc_id_p = new_id; // save new id for later delete 2196 } 2197 return id; 2198 } 2199 2200 2201 // Common code to get the jmethodID cache length and the jmethodID 2202 // value at index idnum if there is one. 2203 // 2204 void InstanceKlass::get_jmethod_id_length_value(jmethodID* cache, 2205 size_t idnum, size_t *length_p, jmethodID* id_p) { 2206 assert(cache != NULL, "sanity check"); 2207 assert(length_p != NULL, "sanity check"); 2208 assert(id_p != NULL, "sanity check"); 2209 2210 // cache size is stored in element[0], other elements offset by one 2211 *length_p = (size_t)cache[0]; 2212 if (*length_p <= idnum) { // cache is too short 2213 *id_p = NULL; 2214 } else { 2215 *id_p = cache[idnum+1]; // fetch jmethodID (if any) 2216 } 2217 } 2218 2219 2220 // Lookup a jmethodID, NULL if not found. Do no blocking, no allocations, no handles 2221 jmethodID InstanceKlass::jmethod_id_or_null(Method* method) { 2222 size_t idnum = (size_t)method->method_idnum(); 2223 jmethodID* jmeths = methods_jmethod_ids_acquire(); 2224 size_t length; // length assigned as debugging crumb 2225 jmethodID id = NULL; 2226 if (jmeths != NULL && // If there is a cache 2227 (length = (size_t)jmeths[0]) > idnum) { // and if it is long enough, 2228 id = jmeths[idnum+1]; // Look up the id (may be NULL) 2229 } 2230 return id; 2231 } 2232 2233 inline DependencyContext InstanceKlass::dependencies() { 2234 DependencyContext dep_context(&_dep_context, &_dep_context_last_cleaned); 2235 return dep_context; 2236 } 2237 2238 int InstanceKlass::mark_dependent_nmethods(KlassDepChange& changes) { 2239 return dependencies().mark_dependent_nmethods(changes); 2240 } 2241 2242 void InstanceKlass::add_dependent_nmethod(nmethod* nm) { 2243 dependencies().add_dependent_nmethod(nm); 2244 } 2245 2246 void InstanceKlass::remove_dependent_nmethod(nmethod* nm) { 2247 dependencies().remove_dependent_nmethod(nm); 2248 } 2249 2250 void InstanceKlass::clean_dependency_context() { 2251 dependencies().clean_unloading_dependents(); 2252 } 2253 2254 #ifndef PRODUCT 2255 void InstanceKlass::print_dependent_nmethods(bool verbose) { 2256 dependencies().print_dependent_nmethods(verbose); 2257 } 2258 2259 bool InstanceKlass::is_dependent_nmethod(nmethod* nm) { 2260 return dependencies().is_dependent_nmethod(nm); 2261 } 2262 #endif //PRODUCT 2263 2264 void InstanceKlass::clean_weak_instanceklass_links() { 2265 clean_implementors_list(); 2266 clean_method_data(); 2267 } 2268 2269 void InstanceKlass::clean_implementors_list() { 2270 assert(is_loader_alive(), "this klass should be live"); 2271 if (is_interface()) { 2272 assert (ClassUnloading, "only called for ClassUnloading"); 2273 for (;;) { 2274 // Use load_acquire due to competing with inserts 2275 Klass* impl = Atomic::load_acquire(adr_implementor()); 2276 if (impl != NULL && !impl->is_loader_alive()) { 2277 // NULL this field, might be an unloaded klass or NULL 2278 Klass* volatile* klass = adr_implementor(); 2279 if (Atomic::cmpxchg(klass, impl, (Klass*)NULL) == impl) { 2280 // Successfully unlinking implementor. 2281 if (log_is_enabled(Trace, class, unload)) { 2282 ResourceMark rm; 2283 log_trace(class, unload)("unlinking class (implementor): %s", impl->external_name()); 2284 } 2285 return; 2286 } 2287 } else { 2288 return; 2289 } 2290 } 2291 } 2292 } 2293 2294 void InstanceKlass::clean_method_data() { 2295 for (int m = 0; m < methods()->length(); m++) { 2296 MethodData* mdo = methods()->at(m)->method_data(); 2297 if (mdo != NULL) { 2298 MutexLocker ml(SafepointSynchronize::is_at_safepoint() ? NULL : mdo->extra_data_lock()); 2299 mdo->clean_method_data(/*always_clean*/false); 2300 } 2301 } 2302 } 2303 2304 bool InstanceKlass::supers_have_passed_fingerprint_checks() { 2305 if (java_super() != NULL && !java_super()->has_passed_fingerprint_check()) { 2306 ResourceMark rm; 2307 log_trace(class, fingerprint)("%s : super %s not fingerprinted", external_name(), java_super()->external_name()); 2308 return false; 2309 } 2310 2311 Array<InstanceKlass*>* local_interfaces = this->local_interfaces(); 2312 if (local_interfaces != NULL) { 2313 int length = local_interfaces->length(); 2314 for (int i = 0; i < length; i++) { 2315 InstanceKlass* intf = local_interfaces->at(i); 2316 if (!intf->has_passed_fingerprint_check()) { 2317 ResourceMark rm; 2318 log_trace(class, fingerprint)("%s : interface %s not fingerprinted", external_name(), intf->external_name()); 2319 return false; 2320 } 2321 } 2322 } 2323 2324 return true; 2325 } 2326 2327 bool InstanceKlass::should_store_fingerprint(bool is_hidden_or_anonymous) { 2328 #if INCLUDE_AOT 2329 // We store the fingerprint into the InstanceKlass only in the following 2 cases: 2330 if (CalculateClassFingerprint) { 2331 // (1) We are running AOT to generate a shared library. 2332 return true; 2333 } 2334 if (Arguments::is_dumping_archive()) { 2335 // (2) We are running -Xshare:dump or -XX:ArchiveClassesAtExit to create a shared archive 2336 return true; 2337 } 2338 if (UseAOT && is_hidden_or_anonymous) { 2339 // (3) We are using AOT code from a shared library and see a hidden or unsafe anonymous class 2340 return true; 2341 } 2342 #endif 2343 2344 // In all other cases we might set the _misc_has_passed_fingerprint_check bit, 2345 // but do not store the 64-bit fingerprint to save space. 2346 return false; 2347 } 2348 2349 bool InstanceKlass::has_stored_fingerprint() const { 2350 #if INCLUDE_AOT 2351 return should_store_fingerprint() || is_shared(); 2352 #else 2353 return false; 2354 #endif 2355 } 2356 2357 uint64_t InstanceKlass::get_stored_fingerprint() const { 2358 address adr = adr_fingerprint(); 2359 if (adr != NULL) { 2360 return (uint64_t)Bytes::get_native_u8(adr); // adr may not be 64-bit aligned 2361 } 2362 return 0; 2363 } 2364 2365 void InstanceKlass::store_fingerprint(uint64_t fingerprint) { 2366 address adr = adr_fingerprint(); 2367 if (adr != NULL) { 2368 Bytes::put_native_u8(adr, (u8)fingerprint); // adr may not be 64-bit aligned 2369 2370 ResourceMark rm; 2371 log_trace(class, fingerprint)("stored as " PTR64_FORMAT " for class %s", fingerprint, external_name()); 2372 } 2373 } 2374 2375 void InstanceKlass::metaspace_pointers_do(MetaspaceClosure* it) { 2376 Klass::metaspace_pointers_do(it); 2377 2378 if (log_is_enabled(Trace, cds)) { 2379 ResourceMark rm; 2380 log_trace(cds)("Iter(InstanceKlass): %p (%s)", this, external_name()); 2381 } 2382 2383 it->push(&_annotations); 2384 it->push((Klass**)&_array_klasses); 2385 it->push(&_constants); 2386 it->push(&_inner_classes); 2387 #if INCLUDE_JVMTI 2388 it->push(&_previous_versions); 2389 #endif 2390 it->push(&_methods); 2391 it->push(&_default_methods); 2392 it->push(&_local_interfaces); 2393 it->push(&_transitive_interfaces); 2394 it->push(&_method_ordering); 2395 it->push(&_default_vtable_indices); 2396 it->push(&_fields); 2397 2398 if (itable_length() > 0) { 2399 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable(); 2400 int method_table_offset_in_words = ioe->offset()/wordSize; 2401 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words()) 2402 / itableOffsetEntry::size(); 2403 2404 for (int i = 0; i < nof_interfaces; i ++, ioe ++) { 2405 if (ioe->interface_klass() != NULL) { 2406 it->push(ioe->interface_klass_addr()); 2407 itableMethodEntry* ime = ioe->first_method_entry(this); 2408 int n = klassItable::method_count_for_interface(ioe->interface_klass()); 2409 for (int index = 0; index < n; index ++) { 2410 it->push(ime[index].method_addr()); 2411 } 2412 } 2413 } 2414 } 2415 2416 it->push(&_nest_members); 2417 it->push(&_record_components); 2418 } 2419 2420 void InstanceKlass::remove_unshareable_info() { 2421 Klass::remove_unshareable_info(); 2422 2423 if (SystemDictionaryShared::has_class_failed_verification(this)) { 2424 // Classes are attempted to link during dumping and may fail, 2425 // but these classes are still in the dictionary and class list in CLD. 2426 // If the class has failed verification, there is nothing else to remove. 2427 return; 2428 } 2429 2430 // Reset to the 'allocated' state to prevent any premature accessing to 2431 // a shared class at runtime while the class is still being loaded and 2432 // restored. A class' init_state is set to 'loaded' at runtime when it's 2433 // being added to class hierarchy (see SystemDictionary:::add_to_hierarchy()). 2434 _init_state = allocated; 2435 2436 { // Otherwise this needs to take out the Compile_lock. 2437 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint"); 2438 init_implementor(); 2439 } 2440 2441 constants()->remove_unshareable_info(); 2442 2443 for (int i = 0; i < methods()->length(); i++) { 2444 Method* m = methods()->at(i); 2445 m->remove_unshareable_info(); 2446 } 2447 2448 // do array classes also. 2449 if (array_klasses() != NULL) { 2450 array_klasses()->remove_unshareable_info(); 2451 } 2452 2453 // These are not allocated from metaspace. They are safe to set to NULL. 2454 _source_debug_extension = NULL; 2455 _dep_context = NULL; 2456 _osr_nmethods_head = NULL; 2457 #if INCLUDE_JVMTI 2458 _breakpoints = NULL; 2459 _previous_versions = NULL; 2460 _cached_class_file = NULL; 2461 _jvmti_cached_class_field_map = NULL; 2462 #endif 2463 2464 _init_thread = NULL; 2465 _methods_jmethod_ids = NULL; 2466 _jni_ids = NULL; 2467 _oop_map_cache = NULL; 2468 // clear _nest_host to ensure re-load at runtime 2469 _nest_host = NULL; 2470 _package_entry = NULL; 2471 _dep_context_last_cleaned = 0; 2472 } 2473 2474 void InstanceKlass::remove_java_mirror() { 2475 Klass::remove_java_mirror(); 2476 2477 // do array classes also. 2478 if (array_klasses() != NULL) { 2479 array_klasses()->remove_java_mirror(); 2480 } 2481 } 2482 2483 void InstanceKlass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain, 2484 PackageEntry* pkg_entry, TRAPS) { 2485 // SystemDictionary::add_to_hierarchy() sets the init_state to loaded 2486 // before the InstanceKlass is added to the SystemDictionary. Make 2487 // sure the current state is <loaded. 2488 assert(!is_loaded(), "invalid init state"); 2489 set_package(loader_data, pkg_entry, CHECK); 2490 Klass::restore_unshareable_info(loader_data, protection_domain, CHECK); 2491 2492 Array<Method*>* methods = this->methods(); 2493 int num_methods = methods->length(); 2494 for (int index = 0; index < num_methods; ++index) { 2495 methods->at(index)->restore_unshareable_info(CHECK); 2496 } 2497 if (JvmtiExport::has_redefined_a_class()) { 2498 // Reinitialize vtable because RedefineClasses may have changed some 2499 // entries in this vtable for super classes so the CDS vtable might 2500 // point to old or obsolete entries. RedefineClasses doesn't fix up 2501 // vtables in the shared system dictionary, only the main one. 2502 // It also redefines the itable too so fix that too. 2503 vtable().initialize_vtable(false, CHECK); 2504 itable().initialize_itable(false, CHECK); 2505 } 2506 2507 // restore constant pool resolved references 2508 constants()->restore_unshareable_info(CHECK); 2509 2510 if (array_klasses() != NULL) { 2511 // Array classes have null protection domain. 2512 // --> see ArrayKlass::complete_create_array_klass() 2513 array_klasses()->restore_unshareable_info(ClassLoaderData::the_null_class_loader_data(), Handle(), CHECK); 2514 } 2515 2516 // Initialize current biased locking state. 2517 if (UseBiasedLocking && BiasedLocking::enabled()) { 2518 set_prototype_header(markWord::biased_locking_prototype()); 2519 } 2520 } 2521 2522 void InstanceKlass::set_shared_class_loader_type(s2 loader_type) { 2523 switch (loader_type) { 2524 case ClassLoader::BOOT_LOADER: 2525 _misc_flags |= _misc_is_shared_boot_class; 2526 break; 2527 case ClassLoader::PLATFORM_LOADER: 2528 _misc_flags |= _misc_is_shared_platform_class; 2529 break; 2530 case ClassLoader::APP_LOADER: 2531 _misc_flags |= _misc_is_shared_app_class; 2532 break; 2533 default: 2534 ShouldNotReachHere(); 2535 break; 2536 } 2537 } 2538 2539 #if INCLUDE_JVMTI 2540 static void clear_all_breakpoints(Method* m) { 2541 m->clear_all_breakpoints(); 2542 } 2543 #endif 2544 2545 void InstanceKlass::unload_class(InstanceKlass* ik) { 2546 // Release dependencies. 2547 ik->dependencies().remove_all_dependents(); 2548 2549 // notify the debugger 2550 if (JvmtiExport::should_post_class_unload()) { 2551 JvmtiExport::post_class_unload(ik); 2552 } 2553 2554 // notify ClassLoadingService of class unload 2555 ClassLoadingService::notify_class_unloaded(ik); 2556 2557 if (Arguments::is_dumping_archive()) { 2558 SystemDictionaryShared::remove_dumptime_info(ik); 2559 } 2560 2561 if (log_is_enabled(Info, class, unload)) { 2562 ResourceMark rm; 2563 log_info(class, unload)("unloading class %s " INTPTR_FORMAT, ik->external_name(), p2i(ik)); 2564 } 2565 2566 Events::log_class_unloading(Thread::current(), ik); 2567 2568 #if INCLUDE_JFR 2569 assert(ik != NULL, "invariant"); 2570 EventClassUnload event; 2571 event.set_unloadedClass(ik); 2572 event.set_definingClassLoader(ik->class_loader_data()); 2573 event.commit(); 2574 #endif 2575 } 2576 2577 static void method_release_C_heap_structures(Method* m) { 2578 m->release_C_heap_structures(); 2579 } 2580 2581 void InstanceKlass::release_C_heap_structures() { 2582 2583 // Clean up C heap 2584 release_C_heap_structures_internal(); 2585 constants()->release_C_heap_structures(); 2586 2587 // Deallocate and call destructors for MDO mutexes 2588 methods_do(method_release_C_heap_structures); 2589 } 2590 2591 void InstanceKlass::release_C_heap_structures_internal() { 2592 Klass::release_C_heap_structures(); 2593 2594 // Can't release the constant pool here because the constant pool can be 2595 // deallocated separately from the InstanceKlass for default methods and 2596 // redefine classes. 2597 2598 // Deallocate oop map cache 2599 if (_oop_map_cache != NULL) { 2600 delete _oop_map_cache; 2601 _oop_map_cache = NULL; 2602 } 2603 2604 // Deallocate JNI identifiers for jfieldIDs 2605 JNIid::deallocate(jni_ids()); 2606 set_jni_ids(NULL); 2607 2608 jmethodID* jmeths = methods_jmethod_ids_acquire(); 2609 if (jmeths != (jmethodID*)NULL) { 2610 release_set_methods_jmethod_ids(NULL); 2611 FreeHeap(jmeths); 2612 } 2613 2614 assert(_dep_context == NULL, 2615 "dependencies should already be cleaned"); 2616 2617 #if INCLUDE_JVMTI 2618 // Deallocate breakpoint records 2619 if (breakpoints() != 0x0) { 2620 methods_do(clear_all_breakpoints); 2621 assert(breakpoints() == 0x0, "should have cleared breakpoints"); 2622 } 2623 2624 // deallocate the cached class file 2625 if (_cached_class_file != NULL) { 2626 os::free(_cached_class_file); 2627 _cached_class_file = NULL; 2628 } 2629 #endif 2630 2631 FREE_C_HEAP_ARRAY(char, _source_debug_extension); 2632 } 2633 2634 void InstanceKlass::set_source_debug_extension(const char* array, int length) { 2635 if (array == NULL) { 2636 _source_debug_extension = NULL; 2637 } else { 2638 // Adding one to the attribute length in order to store a null terminator 2639 // character could cause an overflow because the attribute length is 2640 // already coded with an u4 in the classfile, but in practice, it's 2641 // unlikely to happen. 2642 assert((length+1) > length, "Overflow checking"); 2643 char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass); 2644 for (int i = 0; i < length; i++) { 2645 sde[i] = array[i]; 2646 } 2647 sde[length] = '\0'; 2648 _source_debug_extension = sde; 2649 } 2650 } 2651 2652 const char* InstanceKlass::signature_name() const { 2653 int hash_len = 0; 2654 char hash_buf[40]; 2655 2656 // If this is an unsafe anonymous class, append a hash to make the name unique 2657 if (is_unsafe_anonymous()) { 2658 intptr_t hash = (java_mirror() != NULL) ? java_mirror()->identity_hash() : 0; 2659 jio_snprintf(hash_buf, sizeof(hash_buf), "/" UINTX_FORMAT, (uintx)hash); 2660 hash_len = (int)strlen(hash_buf); 2661 } 2662 2663 // Get the internal name as a c string 2664 const char* src = (const char*) (name()->as_C_string()); 2665 const int src_length = (int)strlen(src); 2666 2667 char* dest = NEW_RESOURCE_ARRAY(char, src_length + hash_len + 3); 2668 2669 // Add L as type indicator 2670 int dest_index = 0; 2671 dest[dest_index++] = JVM_SIGNATURE_CLASS; 2672 2673 // Add the actual class name 2674 for (int src_index = 0; src_index < src_length; ) { 2675 dest[dest_index++] = src[src_index++]; 2676 } 2677 2678 if (is_hidden()) { // Replace the last '+' with a '.'. 2679 for (int index = (int)src_length; index > 0; index--) { 2680 if (dest[index] == '+') { 2681 dest[index] = JVM_SIGNATURE_DOT; 2682 break; 2683 } 2684 } 2685 } 2686 2687 // If we have a hash, append it 2688 for (int hash_index = 0; hash_index < hash_len; ) { 2689 dest[dest_index++] = hash_buf[hash_index++]; 2690 } 2691 2692 // Add the semicolon and the NULL 2693 dest[dest_index++] = JVM_SIGNATURE_ENDCLASS; 2694 dest[dest_index] = '\0'; 2695 return dest; 2696 } 2697 2698 ModuleEntry* InstanceKlass::module() const { 2699 // For an unsafe anonymous class return the host class' module 2700 if (is_unsafe_anonymous()) { 2701 assert(unsafe_anonymous_host() != NULL, "unsafe anonymous class must have a host class"); 2702 return unsafe_anonymous_host()->module(); 2703 } 2704 2705 if (is_hidden() && 2706 in_unnamed_package() && 2707 class_loader_data()->has_class_mirror_holder()) { 2708 // For a non-strong hidden class defined to an unnamed package, 2709 // its (class held) CLD will not have an unnamed module created for it. 2710 // Two choices to find the correct ModuleEntry: 2711 // 1. If hidden class is within a nest, use nest host's module 2712 // 2. Find the unnamed module off from the class loader 2713 // For now option #2 is used since a nest host is not set until 2714 // after the instance class is created in jvm_lookup_define_class(). 2715 if (class_loader_data()->is_boot_class_loader_data()) { 2716 return ClassLoaderData::the_null_class_loader_data()->unnamed_module(); 2717 } else { 2718 oop module = java_lang_ClassLoader::unnamedModule(class_loader_data()->class_loader()); 2719 assert(java_lang_Module::is_instance(module), "Not an instance of java.lang.Module"); 2720 return java_lang_Module::module_entry(module); 2721 } 2722 } 2723 2724 // Class is in a named package 2725 if (!in_unnamed_package()) { 2726 return _package_entry->module(); 2727 } 2728 2729 // Class is in an unnamed package, return its loader's unnamed module 2730 return class_loader_data()->unnamed_module(); 2731 } 2732 2733 void InstanceKlass::set_package(ClassLoaderData* loader_data, PackageEntry* pkg_entry, TRAPS) { 2734 2735 // ensure java/ packages only loaded by boot or platform builtin loaders 2736 // not needed for shared class since CDS does not archive prohibited classes. 2737 if (!is_shared()) { 2738 check_prohibited_package(name(), loader_data, CHECK); 2739 } 2740 2741 TempNewSymbol pkg_name = pkg_entry != NULL ? pkg_entry->name() : ClassLoader::package_from_class_name(name()); 2742 2743 if (pkg_name != NULL && loader_data != NULL) { 2744 2745 // Find in class loader's package entry table. 2746 _package_entry = pkg_entry != NULL ? pkg_entry : loader_data->packages()->lookup_only(pkg_name); 2747 2748 // If the package name is not found in the loader's package 2749 // entry table, it is an indication that the package has not 2750 // been defined. Consider it defined within the unnamed module. 2751 if (_package_entry == NULL) { 2752 2753 if (!ModuleEntryTable::javabase_defined()) { 2754 // Before java.base is defined during bootstrapping, define all packages in 2755 // the java.base module. If a non-java.base package is erroneously placed 2756 // in the java.base module it will be caught later when java.base 2757 // is defined by ModuleEntryTable::verify_javabase_packages check. 2758 assert(ModuleEntryTable::javabase_moduleEntry() != NULL, JAVA_BASE_NAME " module is NULL"); 2759 _package_entry = loader_data->packages()->lookup(pkg_name, ModuleEntryTable::javabase_moduleEntry()); 2760 } else { 2761 assert(loader_data->unnamed_module() != NULL, "unnamed module is NULL"); 2762 _package_entry = loader_data->packages()->lookup(pkg_name, 2763 loader_data->unnamed_module()); 2764 } 2765 2766 // A package should have been successfully created 2767 DEBUG_ONLY(ResourceMark rm(THREAD)); 2768 assert(_package_entry != NULL, "Package entry for class %s not found, loader %s", 2769 name()->as_C_string(), loader_data->loader_name_and_id()); 2770 } 2771 2772 if (log_is_enabled(Debug, module)) { 2773 ResourceMark rm(THREAD); 2774 ModuleEntry* m = _package_entry->module(); 2775 log_trace(module)("Setting package: class: %s, package: %s, loader: %s, module: %s", 2776 external_name(), 2777 pkg_name->as_C_string(), 2778 loader_data->loader_name_and_id(), 2779 (m->is_named() ? m->name()->as_C_string() : UNNAMED_MODULE)); 2780 } 2781 } else { 2782 ResourceMark rm(THREAD); 2783 log_trace(module)("Setting package: class: %s, package: unnamed, loader: %s, module: %s", 2784 external_name(), 2785 (loader_data != NULL) ? loader_data->loader_name_and_id() : "NULL", 2786 UNNAMED_MODULE); 2787 } 2788 } 2789 2790 // Function set_classpath_index checks if the package of the InstanceKlass is in the 2791 // boot loader's package entry table. If so, then it sets the classpath_index 2792 // in the package entry record. 2793 // 2794 // The classpath_index field is used to find the entry on the boot loader class 2795 // path for packages with classes loaded by the boot loader from -Xbootclasspath/a 2796 // in an unnamed module. It is also used to indicate (for all packages whose 2797 // classes are loaded by the boot loader) that at least one of the package's 2798 // classes has been loaded. 2799 void InstanceKlass::set_classpath_index(s2 path_index, TRAPS) { 2800 if (_package_entry != NULL) { 2801 DEBUG_ONLY(PackageEntryTable* pkg_entry_tbl = ClassLoaderData::the_null_class_loader_data()->packages();) 2802 assert(pkg_entry_tbl->lookup_only(_package_entry->name()) == _package_entry, "Should be same"); 2803 assert(path_index != -1, "Unexpected classpath_index"); 2804 _package_entry->set_classpath_index(path_index); 2805 } 2806 } 2807 2808 // different versions of is_same_class_package 2809 2810 bool InstanceKlass::is_same_class_package(const Klass* class2) const { 2811 oop classloader1 = this->class_loader(); 2812 PackageEntry* classpkg1 = this->package(); 2813 if (class2->is_objArray_klass()) { 2814 class2 = ObjArrayKlass::cast(class2)->bottom_klass(); 2815 } 2816 2817 oop classloader2; 2818 PackageEntry* classpkg2; 2819 if (class2->is_instance_klass()) { 2820 classloader2 = class2->class_loader(); 2821 classpkg2 = class2->package(); 2822 } else { 2823 assert(class2->is_typeArray_klass(), "should be type array"); 2824 classloader2 = NULL; 2825 classpkg2 = NULL; 2826 } 2827 2828 // Same package is determined by comparing class loader 2829 // and package entries. Both must be the same. This rule 2830 // applies even to classes that are defined in the unnamed 2831 // package, they still must have the same class loader. 2832 if ((classloader1 == classloader2) && (classpkg1 == classpkg2)) { 2833 return true; 2834 } 2835 2836 return false; 2837 } 2838 2839 // return true if this class and other_class are in the same package. Classloader 2840 // and classname information is enough to determine a class's package 2841 bool InstanceKlass::is_same_class_package(oop other_class_loader, 2842 const Symbol* other_class_name) const { 2843 if (class_loader() != other_class_loader) { 2844 return false; 2845 } 2846 if (name()->fast_compare(other_class_name) == 0) { 2847 return true; 2848 } 2849 2850 { 2851 ResourceMark rm; 2852 2853 bool bad_class_name = false; 2854 TempNewSymbol other_pkg = ClassLoader::package_from_class_name(other_class_name, &bad_class_name); 2855 if (bad_class_name) { 2856 return false; 2857 } 2858 // Check that package_from_class_name() returns NULL, not "", if there is no package. 2859 assert(other_pkg == NULL || other_pkg->utf8_length() > 0, "package name is empty string"); 2860 2861 const Symbol* const this_package_name = 2862 this->package() != NULL ? this->package()->name() : NULL; 2863 2864 if (this_package_name == NULL || other_pkg == NULL) { 2865 // One of the two doesn't have a package. Only return true if the other 2866 // one also doesn't have a package. 2867 return this_package_name == other_pkg; 2868 } 2869 2870 // Check if package is identical 2871 return this_package_name->fast_compare(other_pkg) == 0; 2872 } 2873 } 2874 2875 // Returns true iff super_method can be overridden by a method in targetclassname 2876 // See JLS 3rd edition 8.4.6.1 2877 // Assumes name-signature match 2878 // "this" is InstanceKlass of super_method which must exist 2879 // note that the InstanceKlass of the method in the targetclassname has not always been created yet 2880 bool InstanceKlass::is_override(const methodHandle& super_method, Handle targetclassloader, Symbol* targetclassname, TRAPS) { 2881 // Private methods can not be overridden 2882 if (super_method->is_private()) { 2883 return false; 2884 } 2885 // If super method is accessible, then override 2886 if ((super_method->is_protected()) || 2887 (super_method->is_public())) { 2888 return true; 2889 } 2890 // Package-private methods are not inherited outside of package 2891 assert(super_method->is_package_private(), "must be package private"); 2892 return(is_same_class_package(targetclassloader(), targetclassname)); 2893 } 2894 2895 // Only boot and platform class loaders can define classes in "java/" packages. 2896 void InstanceKlass::check_prohibited_package(Symbol* class_name, 2897 ClassLoaderData* loader_data, 2898 TRAPS) { 2899 if (!loader_data->is_boot_class_loader_data() && 2900 !loader_data->is_platform_class_loader_data() && 2901 class_name != NULL) { 2902 ResourceMark rm(THREAD); 2903 char* name = class_name->as_C_string(); 2904 if (strncmp(name, JAVAPKG, JAVAPKG_LEN) == 0 && name[JAVAPKG_LEN] == '/') { 2905 TempNewSymbol pkg_name = ClassLoader::package_from_class_name(class_name); 2906 assert(pkg_name != NULL, "Error in parsing package name starting with 'java/'"); 2907 name = pkg_name->as_C_string(); 2908 const char* class_loader_name = loader_data->loader_name_and_id(); 2909 StringUtils::replace_no_expand(name, "/", "."); 2910 const char* msg_text1 = "Class loader (instance of): "; 2911 const char* msg_text2 = " tried to load prohibited package name: "; 2912 size_t len = strlen(msg_text1) + strlen(class_loader_name) + strlen(msg_text2) + strlen(name) + 1; 2913 char* message = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, len); 2914 jio_snprintf(message, len, "%s%s%s%s", msg_text1, class_loader_name, msg_text2, name); 2915 THROW_MSG(vmSymbols::java_lang_SecurityException(), message); 2916 } 2917 } 2918 return; 2919 } 2920 2921 bool InstanceKlass::find_inner_classes_attr(int* ooff, int* noff, TRAPS) const { 2922 constantPoolHandle i_cp(THREAD, constants()); 2923 for (InnerClassesIterator iter(this); !iter.done(); iter.next()) { 2924 int ioff = iter.inner_class_info_index(); 2925 if (ioff != 0) { 2926 // Check to see if the name matches the class we're looking for 2927 // before attempting to find the class. 2928 if (i_cp->klass_name_at_matches(this, ioff)) { 2929 Klass* inner_klass = i_cp->klass_at(ioff, CHECK_false); 2930 if (this == inner_klass) { 2931 *ooff = iter.outer_class_info_index(); 2932 *noff = iter.inner_name_index(); 2933 return true; 2934 } 2935 } 2936 } 2937 } 2938 return false; 2939 } 2940 2941 InstanceKlass* InstanceKlass::compute_enclosing_class(bool* inner_is_member, TRAPS) const { 2942 InstanceKlass* outer_klass = NULL; 2943 *inner_is_member = false; 2944 int ooff = 0, noff = 0; 2945 bool has_inner_classes_attr = find_inner_classes_attr(&ooff, &noff, THREAD); 2946 if (has_inner_classes_attr) { 2947 constantPoolHandle i_cp(THREAD, constants()); 2948 if (ooff != 0) { 2949 Klass* ok = i_cp->klass_at(ooff, CHECK_NULL); 2950 outer_klass = InstanceKlass::cast(ok); 2951 *inner_is_member = true; 2952 } 2953 if (NULL == outer_klass) { 2954 // It may be a local or anonymous class; try for that. 2955 int encl_method_class_idx = enclosing_method_class_index(); 2956 if (encl_method_class_idx != 0) { 2957 Klass* ok = i_cp->klass_at(encl_method_class_idx, CHECK_NULL); 2958 outer_klass = InstanceKlass::cast(ok); 2959 *inner_is_member = false; 2960 } 2961 } 2962 } 2963 2964 // If no inner class attribute found for this class. 2965 if (NULL == outer_klass) return NULL; 2966 2967 // Throws an exception if outer klass has not declared k as an inner klass 2968 // We need evidence that each klass knows about the other, or else 2969 // the system could allow a spoof of an inner class to gain access rights. 2970 Reflection::check_for_inner_class(outer_klass, this, *inner_is_member, CHECK_NULL); 2971 return outer_klass; 2972 } 2973 2974 jint InstanceKlass::compute_modifier_flags(TRAPS) const { 2975 jint access = access_flags().as_int(); 2976 2977 // But check if it happens to be member class. 2978 InnerClassesIterator iter(this); 2979 for (; !iter.done(); iter.next()) { 2980 int ioff = iter.inner_class_info_index(); 2981 // Inner class attribute can be zero, skip it. 2982 // Strange but true: JVM spec. allows null inner class refs. 2983 if (ioff == 0) continue; 2984 2985 // only look at classes that are already loaded 2986 // since we are looking for the flags for our self. 2987 Symbol* inner_name = constants()->klass_name_at(ioff); 2988 if (name() == inner_name) { 2989 // This is really a member class. 2990 access = iter.inner_access_flags(); 2991 break; 2992 } 2993 } 2994 // Remember to strip ACC_SUPER bit 2995 return (access & (~JVM_ACC_SUPER)) & JVM_ACC_WRITTEN_FLAGS; 2996 } 2997 2998 jint InstanceKlass::jvmti_class_status() const { 2999 jint result = 0; 3000 3001 if (is_linked()) { 3002 result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED; 3003 } 3004 3005 if (is_initialized()) { 3006 assert(is_linked(), "Class status is not consistent"); 3007 result |= JVMTI_CLASS_STATUS_INITIALIZED; 3008 } 3009 if (is_in_error_state()) { 3010 result |= JVMTI_CLASS_STATUS_ERROR; 3011 } 3012 return result; 3013 } 3014 3015 Method* InstanceKlass::method_at_itable(Klass* holder, int index, TRAPS) { 3016 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable(); 3017 int method_table_offset_in_words = ioe->offset()/wordSize; 3018 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words()) 3019 / itableOffsetEntry::size(); 3020 3021 for (int cnt = 0 ; ; cnt ++, ioe ++) { 3022 // If the interface isn't implemented by the receiver class, 3023 // the VM should throw IncompatibleClassChangeError. 3024 if (cnt >= nof_interfaces) { 3025 ResourceMark rm(THREAD); 3026 stringStream ss; 3027 bool same_module = (module() == holder->module()); 3028 ss.print("Receiver class %s does not implement " 3029 "the interface %s defining the method to be called " 3030 "(%s%s%s)", 3031 external_name(), holder->external_name(), 3032 (same_module) ? joint_in_module_of_loader(holder) : class_in_module_of_loader(), 3033 (same_module) ? "" : "; ", 3034 (same_module) ? "" : holder->class_in_module_of_loader()); 3035 THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), ss.as_string()); 3036 } 3037 3038 Klass* ik = ioe->interface_klass(); 3039 if (ik == holder) break; 3040 } 3041 3042 itableMethodEntry* ime = ioe->first_method_entry(this); 3043 Method* m = ime[index].method(); 3044 if (m == NULL) { 3045 THROW_NULL(vmSymbols::java_lang_AbstractMethodError()); 3046 } 3047 return m; 3048 } 3049 3050 3051 #if INCLUDE_JVMTI 3052 // update default_methods for redefineclasses for methods that are 3053 // not yet in the vtable due to concurrent subclass define and superinterface 3054 // redefinition 3055 // Note: those in the vtable, should have been updated via adjust_method_entries 3056 void InstanceKlass::adjust_default_methods(bool* trace_name_printed) { 3057 // search the default_methods for uses of either obsolete or EMCP methods 3058 if (default_methods() != NULL) { 3059 for (int index = 0; index < default_methods()->length(); index ++) { 3060 Method* old_method = default_methods()->at(index); 3061 if (old_method == NULL || !old_method->is_old()) { 3062 continue; // skip uninteresting entries 3063 } 3064 assert(!old_method->is_deleted(), "default methods may not be deleted"); 3065 Method* new_method = old_method->get_new_method(); 3066 default_methods()->at_put(index, new_method); 3067 3068 if (log_is_enabled(Info, redefine, class, update)) { 3069 ResourceMark rm; 3070 if (!(*trace_name_printed)) { 3071 log_info(redefine, class, update) 3072 ("adjust: klassname=%s default methods from name=%s", 3073 external_name(), old_method->method_holder()->external_name()); 3074 *trace_name_printed = true; 3075 } 3076 log_debug(redefine, class, update, vtables) 3077 ("default method update: %s(%s) ", 3078 new_method->name()->as_C_string(), new_method->signature()->as_C_string()); 3079 } 3080 } 3081 } 3082 } 3083 #endif // INCLUDE_JVMTI 3084 3085 // On-stack replacement stuff 3086 void InstanceKlass::add_osr_nmethod(nmethod* n) { 3087 assert_lock_strong(CompiledMethod_lock); 3088 #ifndef PRODUCT 3089 if (TieredCompilation) { 3090 nmethod* prev = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), n->comp_level(), true); 3091 assert(prev == NULL || !prev->is_in_use() COMPILER2_PRESENT(|| StressRecompilation), 3092 "redundant OSR recompilation detected. memory leak in CodeCache!"); 3093 } 3094 #endif 3095 // only one compilation can be active 3096 { 3097 assert(n->is_osr_method(), "wrong kind of nmethod"); 3098 n->set_osr_link(osr_nmethods_head()); 3099 set_osr_nmethods_head(n); 3100 // Raise the highest osr level if necessary 3101 if (TieredCompilation) { 3102 Method* m = n->method(); 3103 m->set_highest_osr_comp_level(MAX2(m->highest_osr_comp_level(), n->comp_level())); 3104 } 3105 } 3106 3107 // Get rid of the osr methods for the same bci that have lower levels. 3108 if (TieredCompilation) { 3109 for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) { 3110 nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true); 3111 if (inv != NULL && inv->is_in_use()) { 3112 inv->make_not_entrant(); 3113 } 3114 } 3115 } 3116 } 3117 3118 // Remove osr nmethod from the list. Return true if found and removed. 3119 bool InstanceKlass::remove_osr_nmethod(nmethod* n) { 3120 // This is a short non-blocking critical region, so the no safepoint check is ok. 3121 MutexLocker ml(CompiledMethod_lock->owned_by_self() ? NULL : CompiledMethod_lock 3122 , Mutex::_no_safepoint_check_flag); 3123 assert(n->is_osr_method(), "wrong kind of nmethod"); 3124 nmethod* last = NULL; 3125 nmethod* cur = osr_nmethods_head(); 3126 int max_level = CompLevel_none; // Find the max comp level excluding n 3127 Method* m = n->method(); 3128 // Search for match 3129 bool found = false; 3130 while(cur != NULL && cur != n) { 3131 if (TieredCompilation && m == cur->method()) { 3132 // Find max level before n 3133 max_level = MAX2(max_level, cur->comp_level()); 3134 } 3135 last = cur; 3136 cur = cur->osr_link(); 3137 } 3138 nmethod* next = NULL; 3139 if (cur == n) { 3140 found = true; 3141 next = cur->osr_link(); 3142 if (last == NULL) { 3143 // Remove first element 3144 set_osr_nmethods_head(next); 3145 } else { 3146 last->set_osr_link(next); 3147 } 3148 } 3149 n->set_osr_link(NULL); 3150 if (TieredCompilation) { 3151 cur = next; 3152 while (cur != NULL) { 3153 // Find max level after n 3154 if (m == cur->method()) { 3155 max_level = MAX2(max_level, cur->comp_level()); 3156 } 3157 cur = cur->osr_link(); 3158 } 3159 m->set_highest_osr_comp_level(max_level); 3160 } 3161 return found; 3162 } 3163 3164 int InstanceKlass::mark_osr_nmethods(const Method* m) { 3165 MutexLocker ml(CompiledMethod_lock->owned_by_self() ? NULL : CompiledMethod_lock, 3166 Mutex::_no_safepoint_check_flag); 3167 nmethod* osr = osr_nmethods_head(); 3168 int found = 0; 3169 while (osr != NULL) { 3170 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain"); 3171 if (osr->method() == m) { 3172 osr->mark_for_deoptimization(); 3173 found++; 3174 } 3175 osr = osr->osr_link(); 3176 } 3177 return found; 3178 } 3179 3180 nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const { 3181 MutexLocker ml(CompiledMethod_lock->owned_by_self() ? NULL : CompiledMethod_lock, 3182 Mutex::_no_safepoint_check_flag); 3183 nmethod* osr = osr_nmethods_head(); 3184 nmethod* best = NULL; 3185 while (osr != NULL) { 3186 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain"); 3187 // There can be a time when a c1 osr method exists but we are waiting 3188 // for a c2 version. When c2 completes its osr nmethod we will trash 3189 // the c1 version and only be able to find the c2 version. However 3190 // while we overflow in the c1 code at back branches we don't want to 3191 // try and switch to the same code as we are already running 3192 3193 if (osr->method() == m && 3194 (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) { 3195 if (match_level) { 3196 if (osr->comp_level() == comp_level) { 3197 // Found a match - return it. 3198 return osr; 3199 } 3200 } else { 3201 if (best == NULL || (osr->comp_level() > best->comp_level())) { 3202 if (osr->comp_level() == CompLevel_highest_tier) { 3203 // Found the best possible - return it. 3204 return osr; 3205 } 3206 best = osr; 3207 } 3208 } 3209 } 3210 osr = osr->osr_link(); 3211 } 3212 3213 assert(match_level == false || best == NULL, "shouldn't pick up anything if match_level is set"); 3214 if (best != NULL && best->comp_level() >= comp_level) { 3215 return best; 3216 } 3217 return NULL; 3218 } 3219 3220 // ----------------------------------------------------------------------------------------------------- 3221 // Printing 3222 3223 #ifndef PRODUCT 3224 3225 #define BULLET " - " 3226 3227 static const char* state_names[] = { 3228 "allocated", "loaded", "linked", "being_initialized", "fully_initialized", "initialization_error" 3229 }; 3230 3231 static void print_vtable(intptr_t* start, int len, outputStream* st) { 3232 for (int i = 0; i < len; i++) { 3233 intptr_t e = start[i]; 3234 st->print("%d : " INTPTR_FORMAT, i, e); 3235 if (MetaspaceObj::is_valid((Metadata*)e)) { 3236 st->print(" "); 3237 ((Metadata*)e)->print_value_on(st); 3238 } 3239 st->cr(); 3240 } 3241 } 3242 3243 static void print_vtable(vtableEntry* start, int len, outputStream* st) { 3244 return print_vtable(reinterpret_cast<intptr_t*>(start), len, st); 3245 } 3246 3247 void InstanceKlass::print_on(outputStream* st) const { 3248 assert(is_klass(), "must be klass"); 3249 Klass::print_on(st); 3250 3251 st->print(BULLET"instance size: %d", size_helper()); st->cr(); 3252 st->print(BULLET"klass size: %d", size()); st->cr(); 3253 st->print(BULLET"access: "); access_flags().print_on(st); st->cr(); 3254 st->print(BULLET"state: "); st->print_cr("%s", state_names[_init_state]); 3255 st->print(BULLET"name: "); name()->print_value_on(st); st->cr(); 3256 st->print(BULLET"super: "); Metadata::print_value_on_maybe_null(st, super()); st->cr(); 3257 st->print(BULLET"sub: "); 3258 Klass* sub = subklass(); 3259 int n; 3260 for (n = 0; sub != NULL; n++, sub = sub->next_sibling()) { 3261 if (n < MaxSubklassPrintSize) { 3262 sub->print_value_on(st); 3263 st->print(" "); 3264 } 3265 } 3266 if (n >= MaxSubklassPrintSize) st->print("(" INTX_FORMAT " more klasses...)", n - MaxSubklassPrintSize); 3267 st->cr(); 3268 3269 if (is_interface()) { 3270 st->print_cr(BULLET"nof implementors: %d", nof_implementors()); 3271 if (nof_implementors() == 1) { 3272 st->print_cr(BULLET"implementor: "); 3273 st->print(" "); 3274 implementor()->print_value_on(st); 3275 st->cr(); 3276 } 3277 } 3278 3279 st->print(BULLET"arrays: "); Metadata::print_value_on_maybe_null(st, array_klasses()); st->cr(); 3280 st->print(BULLET"methods: "); methods()->print_value_on(st); st->cr(); 3281 if (Verbose || WizardMode) { 3282 Array<Method*>* method_array = methods(); 3283 for (int i = 0; i < method_array->length(); i++) { 3284 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr(); 3285 } 3286 } 3287 st->print(BULLET"method ordering: "); method_ordering()->print_value_on(st); st->cr(); 3288 st->print(BULLET"default_methods: "); default_methods()->print_value_on(st); st->cr(); 3289 if (Verbose && default_methods() != NULL) { 3290 Array<Method*>* method_array = default_methods(); 3291 for (int i = 0; i < method_array->length(); i++) { 3292 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr(); 3293 } 3294 } 3295 if (default_vtable_indices() != NULL) { 3296 st->print(BULLET"default vtable indices: "); default_vtable_indices()->print_value_on(st); st->cr(); 3297 } 3298 st->print(BULLET"local interfaces: "); local_interfaces()->print_value_on(st); st->cr(); 3299 st->print(BULLET"trans. interfaces: "); transitive_interfaces()->print_value_on(st); st->cr(); 3300 st->print(BULLET"constants: "); constants()->print_value_on(st); st->cr(); 3301 if (class_loader_data() != NULL) { 3302 st->print(BULLET"class loader data: "); 3303 class_loader_data()->print_value_on(st); 3304 st->cr(); 3305 } 3306 st->print(BULLET"unsafe anonymous host class: "); Metadata::print_value_on_maybe_null(st, unsafe_anonymous_host()); st->cr(); 3307 if (source_file_name() != NULL) { 3308 st->print(BULLET"source file: "); 3309 source_file_name()->print_value_on(st); 3310 st->cr(); 3311 } 3312 if (source_debug_extension() != NULL) { 3313 st->print(BULLET"source debug extension: "); 3314 st->print("%s", source_debug_extension()); 3315 st->cr(); 3316 } 3317 st->print(BULLET"class annotations: "); class_annotations()->print_value_on(st); st->cr(); 3318 st->print(BULLET"class type annotations: "); class_type_annotations()->print_value_on(st); st->cr(); 3319 st->print(BULLET"field annotations: "); fields_annotations()->print_value_on(st); st->cr(); 3320 st->print(BULLET"field type annotations: "); fields_type_annotations()->print_value_on(st); st->cr(); 3321 { 3322 bool have_pv = false; 3323 // previous versions are linked together through the InstanceKlass 3324 for (InstanceKlass* pv_node = previous_versions(); 3325 pv_node != NULL; 3326 pv_node = pv_node->previous_versions()) { 3327 if (!have_pv) 3328 st->print(BULLET"previous version: "); 3329 have_pv = true; 3330 pv_node->constants()->print_value_on(st); 3331 } 3332 if (have_pv) st->cr(); 3333 } 3334 3335 if (generic_signature() != NULL) { 3336 st->print(BULLET"generic signature: "); 3337 generic_signature()->print_value_on(st); 3338 st->cr(); 3339 } 3340 st->print(BULLET"inner classes: "); inner_classes()->print_value_on(st); st->cr(); 3341 st->print(BULLET"nest members: "); nest_members()->print_value_on(st); st->cr(); 3342 if (record_components() != NULL) { 3343 st->print(BULLET"record components: "); record_components()->print_value_on(st); st->cr(); 3344 } 3345 if (java_mirror() != NULL) { 3346 st->print(BULLET"java mirror: "); 3347 java_mirror()->print_value_on(st); 3348 st->cr(); 3349 } else { 3350 st->print_cr(BULLET"java mirror: NULL"); 3351 } 3352 st->print(BULLET"vtable length %d (start addr: " INTPTR_FORMAT ")", vtable_length(), p2i(start_of_vtable())); st->cr(); 3353 if (vtable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_vtable(), vtable_length(), st); 3354 st->print(BULLET"itable length %d (start addr: " INTPTR_FORMAT ")", itable_length(), p2i(start_of_itable())); st->cr(); 3355 if (itable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_itable(), itable_length(), st); 3356 st->print_cr(BULLET"---- static fields (%d words):", static_field_size()); 3357 FieldPrinter print_static_field(st); 3358 ((InstanceKlass*)this)->do_local_static_fields(&print_static_field); 3359 st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size()); 3360 FieldPrinter print_nonstatic_field(st); 3361 InstanceKlass* ik = const_cast<InstanceKlass*>(this); 3362 ik->do_nonstatic_fields(&print_nonstatic_field); 3363 3364 st->print(BULLET"non-static oop maps: "); 3365 OopMapBlock* map = start_of_nonstatic_oop_maps(); 3366 OopMapBlock* end_map = map + nonstatic_oop_map_count(); 3367 while (map < end_map) { 3368 st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1)); 3369 map++; 3370 } 3371 st->cr(); 3372 } 3373 3374 #endif //PRODUCT 3375 3376 void InstanceKlass::print_value_on(outputStream* st) const { 3377 assert(is_klass(), "must be klass"); 3378 if (Verbose || WizardMode) access_flags().print_on(st); 3379 name()->print_value_on(st); 3380 } 3381 3382 #ifndef PRODUCT 3383 3384 void FieldPrinter::do_field(fieldDescriptor* fd) { 3385 _st->print(BULLET); 3386 if (_obj == NULL) { 3387 fd->print_on(_st); 3388 _st->cr(); 3389 } else { 3390 fd->print_on_for(_st, _obj); 3391 _st->cr(); 3392 } 3393 } 3394 3395 3396 void InstanceKlass::oop_print_on(oop obj, outputStream* st) { 3397 Klass::oop_print_on(obj, st); 3398 3399 if (this == SystemDictionary::String_klass()) { 3400 typeArrayOop value = java_lang_String::value(obj); 3401 juint length = java_lang_String::length(obj); 3402 if (value != NULL && 3403 value->is_typeArray() && 3404 length <= (juint) value->length()) { 3405 st->print(BULLET"string: "); 3406 java_lang_String::print(obj, st); 3407 st->cr(); 3408 if (!WizardMode) return; // that is enough 3409 } 3410 } 3411 3412 st->print_cr(BULLET"---- fields (total size %d words):", oop_size(obj)); 3413 FieldPrinter print_field(st, obj); 3414 do_nonstatic_fields(&print_field); 3415 3416 if (this == SystemDictionary::Class_klass()) { 3417 st->print(BULLET"signature: "); 3418 java_lang_Class::print_signature(obj, st); 3419 st->cr(); 3420 Klass* mirrored_klass = java_lang_Class::as_Klass(obj); 3421 st->print(BULLET"fake entry for mirror: "); 3422 Metadata::print_value_on_maybe_null(st, mirrored_klass); 3423 st->cr(); 3424 Klass* array_klass = java_lang_Class::array_klass_acquire(obj); 3425 st->print(BULLET"fake entry for array: "); 3426 Metadata::print_value_on_maybe_null(st, array_klass); 3427 st->cr(); 3428 st->print_cr(BULLET"fake entry for oop_size: %d", java_lang_Class::oop_size(obj)); 3429 st->print_cr(BULLET"fake entry for static_oop_field_count: %d", java_lang_Class::static_oop_field_count(obj)); 3430 Klass* real_klass = java_lang_Class::as_Klass(obj); 3431 if (real_klass != NULL && real_klass->is_instance_klass()) { 3432 InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field); 3433 } 3434 } else if (this == SystemDictionary::MethodType_klass()) { 3435 st->print(BULLET"signature: "); 3436 java_lang_invoke_MethodType::print_signature(obj, st); 3437 st->cr(); 3438 } 3439 } 3440 3441 bool InstanceKlass::verify_itable_index(int i) { 3442 int method_count = klassItable::method_count_for_interface(this); 3443 assert(i >= 0 && i < method_count, "index out of bounds"); 3444 return true; 3445 } 3446 3447 #endif //PRODUCT 3448 3449 void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) { 3450 st->print("a "); 3451 name()->print_value_on(st); 3452 obj->print_address_on(st); 3453 if (this == SystemDictionary::String_klass() 3454 && java_lang_String::value(obj) != NULL) { 3455 ResourceMark rm; 3456 int len = java_lang_String::length(obj); 3457 int plen = (len < 24 ? len : 12); 3458 char* str = java_lang_String::as_utf8_string(obj, 0, plen); 3459 st->print(" = \"%s\"", str); 3460 if (len > plen) 3461 st->print("...[%d]", len); 3462 } else if (this == SystemDictionary::Class_klass()) { 3463 Klass* k = java_lang_Class::as_Klass(obj); 3464 st->print(" = "); 3465 if (k != NULL) { 3466 k->print_value_on(st); 3467 } else { 3468 const char* tname = type2name(java_lang_Class::primitive_type(obj)); 3469 st->print("%s", tname ? tname : "type?"); 3470 } 3471 } else if (this == SystemDictionary::MethodType_klass()) { 3472 st->print(" = "); 3473 java_lang_invoke_MethodType::print_signature(obj, st); 3474 } else if (java_lang_boxing_object::is_instance(obj)) { 3475 st->print(" = "); 3476 java_lang_boxing_object::print(obj, st); 3477 } else if (this == SystemDictionary::LambdaForm_klass()) { 3478 oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj); 3479 if (vmentry != NULL) { 3480 st->print(" => "); 3481 vmentry->print_value_on(st); 3482 } 3483 } else if (this == SystemDictionary::MemberName_klass()) { 3484 Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj); 3485 if (vmtarget != NULL) { 3486 st->print(" = "); 3487 vmtarget->print_value_on(st); 3488 } else { 3489 java_lang_invoke_MemberName::clazz(obj)->print_value_on(st); 3490 st->print("."); 3491 java_lang_invoke_MemberName::name(obj)->print_value_on(st); 3492 } 3493 } 3494 } 3495 3496 const char* InstanceKlass::internal_name() const { 3497 return external_name(); 3498 } 3499 3500 void InstanceKlass::print_class_load_logging(ClassLoaderData* loader_data, 3501 const char* module_name, 3502 const ClassFileStream* cfs) const { 3503 if (!log_is_enabled(Info, class, load)) { 3504 return; 3505 } 3506 3507 ResourceMark rm; 3508 LogMessage(class, load) msg; 3509 stringStream info_stream; 3510 3511 // Name and class hierarchy info 3512 info_stream.print("%s", external_name()); 3513 3514 // Source 3515 if (cfs != NULL) { 3516 if (cfs->source() != NULL) { 3517 if (module_name != NULL) { 3518 // When the boot loader created the stream, it didn't know the module name 3519 // yet. Let's format it now. 3520 if (cfs->from_boot_loader_modules_image()) { 3521 info_stream.print(" source: jrt:/%s", module_name); 3522 } else { 3523 info_stream.print(" source: %s", cfs->source()); 3524 } 3525 } else { 3526 info_stream.print(" source: %s", cfs->source()); 3527 } 3528 } else if (loader_data == ClassLoaderData::the_null_class_loader_data()) { 3529 Thread* THREAD = Thread::current(); 3530 Klass* caller = 3531 THREAD->is_Java_thread() 3532 ? ((JavaThread*)THREAD)->security_get_caller_class(1) 3533 : NULL; 3534 // caller can be NULL, for example, during a JVMTI VM_Init hook 3535 if (caller != NULL) { 3536 info_stream.print(" source: instance of %s", caller->external_name()); 3537 } else { 3538 // source is unknown 3539 } 3540 } else { 3541 oop class_loader = loader_data->class_loader(); 3542 info_stream.print(" source: %s", class_loader->klass()->external_name()); 3543 } 3544 } else { 3545 assert(this->is_shared(), "must be"); 3546 if (MetaspaceShared::is_shared_dynamic((void*)this)) { 3547 info_stream.print(" source: shared objects file (top)"); 3548 } else { 3549 info_stream.print(" source: shared objects file"); 3550 } 3551 } 3552 3553 msg.info("%s", info_stream.as_string()); 3554 3555 if (log_is_enabled(Debug, class, load)) { 3556 stringStream debug_stream; 3557 3558 // Class hierarchy info 3559 debug_stream.print(" klass: " INTPTR_FORMAT " super: " INTPTR_FORMAT, 3560 p2i(this), p2i(superklass())); 3561 3562 // Interfaces 3563 if (local_interfaces() != NULL && local_interfaces()->length() > 0) { 3564 debug_stream.print(" interfaces:"); 3565 int length = local_interfaces()->length(); 3566 for (int i = 0; i < length; i++) { 3567 debug_stream.print(" " INTPTR_FORMAT, 3568 p2i(InstanceKlass::cast(local_interfaces()->at(i)))); 3569 } 3570 } 3571 3572 // Class loader 3573 debug_stream.print(" loader: ["); 3574 loader_data->print_value_on(&debug_stream); 3575 debug_stream.print("]"); 3576 3577 // Classfile checksum 3578 if (cfs) { 3579 debug_stream.print(" bytes: %d checksum: %08x", 3580 cfs->length(), 3581 ClassLoader::crc32(0, (const char*)cfs->buffer(), 3582 cfs->length())); 3583 } 3584 3585 msg.debug("%s", debug_stream.as_string()); 3586 } 3587 } 3588 3589 // Verification 3590 3591 class VerifyFieldClosure: public BasicOopIterateClosure { 3592 protected: 3593 template <class T> void do_oop_work(T* p) { 3594 oop obj = RawAccess<>::oop_load(p); 3595 if (!oopDesc::is_oop_or_null(obj)) { 3596 tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p2i(p), p2i(obj)); 3597 Universe::print_on(tty); 3598 guarantee(false, "boom"); 3599 } 3600 } 3601 public: 3602 virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); } 3603 virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); } 3604 }; 3605 3606 void InstanceKlass::verify_on(outputStream* st) { 3607 #ifndef PRODUCT 3608 // Avoid redundant verifies, this really should be in product. 3609 if (_verify_count == Universe::verify_count()) return; 3610 _verify_count = Universe::verify_count(); 3611 #endif 3612 3613 // Verify Klass 3614 Klass::verify_on(st); 3615 3616 // Verify that klass is present in ClassLoaderData 3617 guarantee(class_loader_data()->contains_klass(this), 3618 "this class isn't found in class loader data"); 3619 3620 // Verify vtables 3621 if (is_linked()) { 3622 // $$$ This used to be done only for m/s collections. Doing it 3623 // always seemed a valid generalization. (DLD -- 6/00) 3624 vtable().verify(st); 3625 } 3626 3627 // Verify first subklass 3628 if (subklass() != NULL) { 3629 guarantee(subklass()->is_klass(), "should be klass"); 3630 } 3631 3632 // Verify siblings 3633 Klass* super = this->super(); 3634 Klass* sib = next_sibling(); 3635 if (sib != NULL) { 3636 if (sib == this) { 3637 fatal("subclass points to itself " PTR_FORMAT, p2i(sib)); 3638 } 3639 3640 guarantee(sib->is_klass(), "should be klass"); 3641 guarantee(sib->super() == super, "siblings should have same superklass"); 3642 } 3643 3644 // Verify local interfaces 3645 if (local_interfaces()) { 3646 Array<InstanceKlass*>* local_interfaces = this->local_interfaces(); 3647 for (int j = 0; j < local_interfaces->length(); j++) { 3648 InstanceKlass* e = local_interfaces->at(j); 3649 guarantee(e->is_klass() && e->is_interface(), "invalid local interface"); 3650 } 3651 } 3652 3653 // Verify transitive interfaces 3654 if (transitive_interfaces() != NULL) { 3655 Array<InstanceKlass*>* transitive_interfaces = this->transitive_interfaces(); 3656 for (int j = 0; j < transitive_interfaces->length(); j++) { 3657 InstanceKlass* e = transitive_interfaces->at(j); 3658 guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface"); 3659 } 3660 } 3661 3662 // Verify methods 3663 if (methods() != NULL) { 3664 Array<Method*>* methods = this->methods(); 3665 for (int j = 0; j < methods->length(); j++) { 3666 guarantee(methods->at(j)->is_method(), "non-method in methods array"); 3667 } 3668 for (int j = 0; j < methods->length() - 1; j++) { 3669 Method* m1 = methods->at(j); 3670 Method* m2 = methods->at(j + 1); 3671 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly"); 3672 } 3673 } 3674 3675 // Verify method ordering 3676 if (method_ordering() != NULL) { 3677 Array<int>* method_ordering = this->method_ordering(); 3678 int length = method_ordering->length(); 3679 if (JvmtiExport::can_maintain_original_method_order() || 3680 ((UseSharedSpaces || Arguments::is_dumping_archive()) && length != 0)) { 3681 guarantee(length == methods()->length(), "invalid method ordering length"); 3682 jlong sum = 0; 3683 for (int j = 0; j < length; j++) { 3684 int original_index = method_ordering->at(j); 3685 guarantee(original_index >= 0, "invalid method ordering index"); 3686 guarantee(original_index < length, "invalid method ordering index"); 3687 sum += original_index; 3688 } 3689 // Verify sum of indices 0,1,...,length-1 3690 guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum"); 3691 } else { 3692 guarantee(length == 0, "invalid method ordering length"); 3693 } 3694 } 3695 3696 // Verify default methods 3697 if (default_methods() != NULL) { 3698 Array<Method*>* methods = this->default_methods(); 3699 for (int j = 0; j < methods->length(); j++) { 3700 guarantee(methods->at(j)->is_method(), "non-method in methods array"); 3701 } 3702 for (int j = 0; j < methods->length() - 1; j++) { 3703 Method* m1 = methods->at(j); 3704 Method* m2 = methods->at(j + 1); 3705 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly"); 3706 } 3707 } 3708 3709 // Verify JNI static field identifiers 3710 if (jni_ids() != NULL) { 3711 jni_ids()->verify(this); 3712 } 3713 3714 // Verify other fields 3715 if (constants() != NULL) { 3716 guarantee(constants()->is_constantPool(), "should be constant pool"); 3717 } 3718 const Klass* anonymous_host = unsafe_anonymous_host(); 3719 if (anonymous_host != NULL) { 3720 guarantee(anonymous_host->is_klass(), "should be klass"); 3721 } 3722 } 3723 3724 void InstanceKlass::oop_verify_on(oop obj, outputStream* st) { 3725 Klass::oop_verify_on(obj, st); 3726 VerifyFieldClosure blk; 3727 obj->oop_iterate(&blk); 3728 } 3729 3730 3731 // JNIid class for jfieldIDs only 3732 // Note to reviewers: 3733 // These JNI functions are just moved over to column 1 and not changed 3734 // in the compressed oops workspace. 3735 JNIid::JNIid(Klass* holder, int offset, JNIid* next) { 3736 _holder = holder; 3737 _offset = offset; 3738 _next = next; 3739 debug_only(_is_static_field_id = false;) 3740 } 3741 3742 3743 JNIid* JNIid::find(int offset) { 3744 JNIid* current = this; 3745 while (current != NULL) { 3746 if (current->offset() == offset) return current; 3747 current = current->next(); 3748 } 3749 return NULL; 3750 } 3751 3752 void JNIid::deallocate(JNIid* current) { 3753 while (current != NULL) { 3754 JNIid* next = current->next(); 3755 delete current; 3756 current = next; 3757 } 3758 } 3759 3760 3761 void JNIid::verify(Klass* holder) { 3762 int first_field_offset = InstanceMirrorKlass::offset_of_static_fields(); 3763 int end_field_offset; 3764 end_field_offset = first_field_offset + (InstanceKlass::cast(holder)->static_field_size() * wordSize); 3765 3766 JNIid* current = this; 3767 while (current != NULL) { 3768 guarantee(current->holder() == holder, "Invalid klass in JNIid"); 3769 #ifdef ASSERT 3770 int o = current->offset(); 3771 if (current->is_static_field_id()) { 3772 guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid"); 3773 } 3774 #endif 3775 current = current->next(); 3776 } 3777 } 3778 3779 void InstanceKlass::set_init_state(ClassState state) { 3780 #ifdef ASSERT 3781 bool good_state = is_shared() ? (_init_state <= state) 3782 : (_init_state < state); 3783 assert(good_state || state == allocated, "illegal state transition"); 3784 #endif 3785 assert(_init_thread == NULL, "should be cleared before state change"); 3786 _init_state = (u1)state; 3787 } 3788 3789 #if INCLUDE_JVMTI 3790 3791 // RedefineClasses() support for previous versions 3792 3793 // Globally, there is at least one previous version of a class to walk 3794 // during class unloading, which is saved because old methods in the class 3795 // are still running. Otherwise the previous version list is cleaned up. 3796 bool InstanceKlass::_has_previous_versions = false; 3797 3798 // Returns true if there are previous versions of a class for class 3799 // unloading only. Also resets the flag to false. purge_previous_version 3800 // will set the flag to true if there are any left, i.e., if there's any 3801 // work to do for next time. This is to avoid the expensive code cache 3802 // walk in CLDG::clean_deallocate_lists(). 3803 bool InstanceKlass::has_previous_versions_and_reset() { 3804 bool ret = _has_previous_versions; 3805 log_trace(redefine, class, iklass, purge)("Class unloading: has_previous_versions = %s", 3806 ret ? "true" : "false"); 3807 _has_previous_versions = false; 3808 return ret; 3809 } 3810 3811 // Purge previous versions before adding new previous versions of the class and 3812 // during class unloading. 3813 void InstanceKlass::purge_previous_version_list() { 3814 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint"); 3815 assert(has_been_redefined(), "Should only be called for main class"); 3816 3817 // Quick exit. 3818 if (previous_versions() == NULL) { 3819 return; 3820 } 3821 3822 // This klass has previous versions so see what we can cleanup 3823 // while it is safe to do so. 3824 3825 int deleted_count = 0; // leave debugging breadcrumbs 3826 int live_count = 0; 3827 ClassLoaderData* loader_data = class_loader_data(); 3828 assert(loader_data != NULL, "should never be null"); 3829 3830 ResourceMark rm; 3831 log_trace(redefine, class, iklass, purge)("%s: previous versions", external_name()); 3832 3833 // previous versions are linked together through the InstanceKlass 3834 InstanceKlass* pv_node = previous_versions(); 3835 InstanceKlass* last = this; 3836 int version = 0; 3837 3838 // check the previous versions list 3839 for (; pv_node != NULL; ) { 3840 3841 ConstantPool* pvcp = pv_node->constants(); 3842 assert(pvcp != NULL, "cp ref was unexpectedly cleared"); 3843 3844 if (!pvcp->on_stack()) { 3845 // If the constant pool isn't on stack, none of the methods 3846 // are executing. Unlink this previous_version. 3847 // The previous version InstanceKlass is on the ClassLoaderData deallocate list 3848 // so will be deallocated during the next phase of class unloading. 3849 log_trace(redefine, class, iklass, purge) 3850 ("previous version " INTPTR_FORMAT " is dead.", p2i(pv_node)); 3851 // For debugging purposes. 3852 pv_node->set_is_scratch_class(); 3853 // Unlink from previous version list. 3854 assert(pv_node->class_loader_data() == loader_data, "wrong loader_data"); 3855 InstanceKlass* next = pv_node->previous_versions(); 3856 pv_node->link_previous_versions(NULL); // point next to NULL 3857 last->link_previous_versions(next); 3858 // Add to the deallocate list after unlinking 3859 loader_data->add_to_deallocate_list(pv_node); 3860 pv_node = next; 3861 deleted_count++; 3862 version++; 3863 continue; 3864 } else { 3865 log_trace(redefine, class, iklass, purge)("previous version " INTPTR_FORMAT " is alive", p2i(pv_node)); 3866 assert(pvcp->pool_holder() != NULL, "Constant pool with no holder"); 3867 guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack"); 3868 live_count++; 3869 // found a previous version for next time we do class unloading 3870 _has_previous_versions = true; 3871 } 3872 3873 // At least one method is live in this previous version. 3874 // Reset dead EMCP methods not to get breakpoints. 3875 // All methods are deallocated when all of the methods for this class are no 3876 // longer running. 3877 Array<Method*>* method_refs = pv_node->methods(); 3878 if (method_refs != NULL) { 3879 log_trace(redefine, class, iklass, purge)("previous methods length=%d", method_refs->length()); 3880 for (int j = 0; j < method_refs->length(); j++) { 3881 Method* method = method_refs->at(j); 3882 3883 if (!method->on_stack()) { 3884 // no breakpoints for non-running methods 3885 if (method->is_running_emcp()) { 3886 method->set_running_emcp(false); 3887 } 3888 } else { 3889 assert (method->is_obsolete() || method->is_running_emcp(), 3890 "emcp method cannot run after emcp bit is cleared"); 3891 log_trace(redefine, class, iklass, purge) 3892 ("purge: %s(%s): prev method @%d in version @%d is alive", 3893 method->name()->as_C_string(), method->signature()->as_C_string(), j, version); 3894 } 3895 } 3896 } 3897 // next previous version 3898 last = pv_node; 3899 pv_node = pv_node->previous_versions(); 3900 version++; 3901 } 3902 log_trace(redefine, class, iklass, purge) 3903 ("previous version stats: live=%d, deleted=%d", live_count, deleted_count); 3904 } 3905 3906 void InstanceKlass::mark_newly_obsolete_methods(Array<Method*>* old_methods, 3907 int emcp_method_count) { 3908 int obsolete_method_count = old_methods->length() - emcp_method_count; 3909 3910 if (emcp_method_count != 0 && obsolete_method_count != 0 && 3911 _previous_versions != NULL) { 3912 // We have a mix of obsolete and EMCP methods so we have to 3913 // clear out any matching EMCP method entries the hard way. 3914 int local_count = 0; 3915 for (int i = 0; i < old_methods->length(); i++) { 3916 Method* old_method = old_methods->at(i); 3917 if (old_method->is_obsolete()) { 3918 // only obsolete methods are interesting 3919 Symbol* m_name = old_method->name(); 3920 Symbol* m_signature = old_method->signature(); 3921 3922 // previous versions are linked together through the InstanceKlass 3923 int j = 0; 3924 for (InstanceKlass* prev_version = _previous_versions; 3925 prev_version != NULL; 3926 prev_version = prev_version->previous_versions(), j++) { 3927 3928 Array<Method*>* method_refs = prev_version->methods(); 3929 for (int k = 0; k < method_refs->length(); k++) { 3930 Method* method = method_refs->at(k); 3931 3932 if (!method->is_obsolete() && 3933 method->name() == m_name && 3934 method->signature() == m_signature) { 3935 // The current RedefineClasses() call has made all EMCP 3936 // versions of this method obsolete so mark it as obsolete 3937 log_trace(redefine, class, iklass, add) 3938 ("%s(%s): flush obsolete method @%d in version @%d", 3939 m_name->as_C_string(), m_signature->as_C_string(), k, j); 3940 3941 method->set_is_obsolete(); 3942 break; 3943 } 3944 } 3945 3946 // The previous loop may not find a matching EMCP method, but 3947 // that doesn't mean that we can optimize and not go any 3948 // further back in the PreviousVersion generations. The EMCP 3949 // method for this generation could have already been made obsolete, 3950 // but there still may be an older EMCP method that has not 3951 // been made obsolete. 3952 } 3953 3954 if (++local_count >= obsolete_method_count) { 3955 // no more obsolete methods so bail out now 3956 break; 3957 } 3958 } 3959 } 3960 } 3961 } 3962 3963 // Save the scratch_class as the previous version if any of the methods are running. 3964 // The previous_versions are used to set breakpoints in EMCP methods and they are 3965 // also used to clean MethodData links to redefined methods that are no longer running. 3966 void InstanceKlass::add_previous_version(InstanceKlass* scratch_class, 3967 int emcp_method_count) { 3968 assert(Thread::current()->is_VM_thread(), 3969 "only VMThread can add previous versions"); 3970 3971 ResourceMark rm; 3972 log_trace(redefine, class, iklass, add) 3973 ("adding previous version ref for %s, EMCP_cnt=%d", scratch_class->external_name(), emcp_method_count); 3974 3975 // Clean out old previous versions for this class 3976 purge_previous_version_list(); 3977 3978 // Mark newly obsolete methods in remaining previous versions. An EMCP method from 3979 // a previous redefinition may be made obsolete by this redefinition. 3980 Array<Method*>* old_methods = scratch_class->methods(); 3981 mark_newly_obsolete_methods(old_methods, emcp_method_count); 3982 3983 // If the constant pool for this previous version of the class 3984 // is not marked as being on the stack, then none of the methods 3985 // in this previous version of the class are on the stack so 3986 // we don't need to add this as a previous version. 3987 ConstantPool* cp_ref = scratch_class->constants(); 3988 if (!cp_ref->on_stack()) { 3989 log_trace(redefine, class, iklass, add)("scratch class not added; no methods are running"); 3990 // For debugging purposes. 3991 scratch_class->set_is_scratch_class(); 3992 scratch_class->class_loader_data()->add_to_deallocate_list(scratch_class); 3993 return; 3994 } 3995 3996 if (emcp_method_count != 0) { 3997 // At least one method is still running, check for EMCP methods 3998 for (int i = 0; i < old_methods->length(); i++) { 3999 Method* old_method = old_methods->at(i); 4000 if (!old_method->is_obsolete() && old_method->on_stack()) { 4001 // if EMCP method (not obsolete) is on the stack, mark as EMCP so that 4002 // we can add breakpoints for it. 4003 4004 // We set the method->on_stack bit during safepoints for class redefinition 4005 // and use this bit to set the is_running_emcp bit. 4006 // After the safepoint, the on_stack bit is cleared and the running emcp 4007 // method may exit. If so, we would set a breakpoint in a method that 4008 // is never reached, but this won't be noticeable to the programmer. 4009 old_method->set_running_emcp(true); 4010 log_trace(redefine, class, iklass, add) 4011 ("EMCP method %s is on_stack " INTPTR_FORMAT, old_method->name_and_sig_as_C_string(), p2i(old_method)); 4012 } else if (!old_method->is_obsolete()) { 4013 log_trace(redefine, class, iklass, add) 4014 ("EMCP method %s is NOT on_stack " INTPTR_FORMAT, old_method->name_and_sig_as_C_string(), p2i(old_method)); 4015 } 4016 } 4017 } 4018 4019 // Add previous version if any methods are still running. 4020 // Set has_previous_version flag for processing during class unloading. 4021 _has_previous_versions = true; 4022 log_trace(redefine, class, iklass, add) ("scratch class added; one of its methods is on_stack."); 4023 assert(scratch_class->previous_versions() == NULL, "shouldn't have a previous version"); 4024 scratch_class->link_previous_versions(previous_versions()); 4025 link_previous_versions(scratch_class); 4026 } // end add_previous_version() 4027 4028 #endif // INCLUDE_JVMTI 4029 4030 Method* InstanceKlass::method_with_idnum(int idnum) { 4031 Method* m = NULL; 4032 if (idnum < methods()->length()) { 4033 m = methods()->at(idnum); 4034 } 4035 if (m == NULL || m->method_idnum() != idnum) { 4036 for (int index = 0; index < methods()->length(); ++index) { 4037 m = methods()->at(index); 4038 if (m->method_idnum() == idnum) { 4039 return m; 4040 } 4041 } 4042 // None found, return null for the caller to handle. 4043 return NULL; 4044 } 4045 return m; 4046 } 4047 4048 4049 Method* InstanceKlass::method_with_orig_idnum(int idnum) { 4050 if (idnum >= methods()->length()) { 4051 return NULL; 4052 } 4053 Method* m = methods()->at(idnum); 4054 if (m != NULL && m->orig_method_idnum() == idnum) { 4055 return m; 4056 } 4057 // Obsolete method idnum does not match the original idnum 4058 for (int index = 0; index < methods()->length(); ++index) { 4059 m = methods()->at(index); 4060 if (m->orig_method_idnum() == idnum) { 4061 return m; 4062 } 4063 } 4064 // None found, return null for the caller to handle. 4065 return NULL; 4066 } 4067 4068 4069 Method* InstanceKlass::method_with_orig_idnum(int idnum, int version) { 4070 InstanceKlass* holder = get_klass_version(version); 4071 if (holder == NULL) { 4072 return NULL; // The version of klass is gone, no method is found 4073 } 4074 Method* method = holder->method_with_orig_idnum(idnum); 4075 return method; 4076 } 4077 4078 #if INCLUDE_JVMTI 4079 JvmtiCachedClassFileData* InstanceKlass::get_cached_class_file() { 4080 return _cached_class_file; 4081 } 4082 4083 jint InstanceKlass::get_cached_class_file_len() { 4084 return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file); 4085 } 4086 4087 unsigned char * InstanceKlass::get_cached_class_file_bytes() { 4088 return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file); 4089 } 4090 #endif