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