1 /* 2 * Copyright (c) 1997, 2018, 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/systemDictionary.hpp" 35 #include "classfile/systemDictionaryShared.hpp" 36 #include "classfile/verifier.hpp" 37 #include "classfile/vmSymbols.hpp" 38 #include "code/dependencyContext.hpp" 39 #include "compiler/compileBroker.hpp" 40 #include "gc/shared/collectedHeap.inline.hpp" 41 #include "interpreter/oopMapCache.hpp" 42 #include "interpreter/rewriter.hpp" 43 #include "jvmtifiles/jvmti.h" 44 #include "logging/log.hpp" 45 #include "logging/logMessage.hpp" 46 #include "logging/logStream.hpp" 47 #include "memory/allocation.inline.hpp" 48 #include "memory/heapInspection.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 "oops/fieldStreams.hpp" 56 #include "oops/instanceClassLoaderKlass.hpp" 57 #include "oops/instanceKlass.inline.hpp" 58 #include "oops/instanceMirrorKlass.hpp" 59 #include "oops/instanceOop.hpp" 60 #include "oops/klass.inline.hpp" 61 #include "oops/method.hpp" 62 #include "oops/oop.inline.hpp" 63 #include "oops/symbol.hpp" 64 #include "prims/jvmtiExport.hpp" 65 #include "prims/jvmtiRedefineClasses.hpp" 66 #include "prims/jvmtiThreadState.hpp" 67 #include "prims/methodComparator.hpp" 68 #include "runtime/atomic.hpp" 69 #include "runtime/fieldDescriptor.hpp" 70 #include "runtime/handles.inline.hpp" 71 #include "runtime/javaCalls.hpp" 72 #include "runtime/mutexLocker.hpp" 73 #include "runtime/orderAccess.hpp" 74 #include "runtime/thread.inline.hpp" 75 #include "services/classLoadingService.hpp" 76 #include "services/threadService.hpp" 77 #include "utilities/dtrace.hpp" 78 #include "utilities/macros.hpp" 79 #include "utilities/stringUtils.hpp" 80 #ifdef COMPILER1 81 #include "c1/c1_Compiler.hpp" 82 #endif 83 84 #ifdef DTRACE_ENABLED 85 86 87 #define HOTSPOT_CLASS_INITIALIZATION_required HOTSPOT_CLASS_INITIALIZATION_REQUIRED 88 #define HOTSPOT_CLASS_INITIALIZATION_recursive HOTSPOT_CLASS_INITIALIZATION_RECURSIVE 89 #define HOTSPOT_CLASS_INITIALIZATION_concurrent HOTSPOT_CLASS_INITIALIZATION_CONCURRENT 90 #define HOTSPOT_CLASS_INITIALIZATION_erroneous HOTSPOT_CLASS_INITIALIZATION_ERRONEOUS 91 #define HOTSPOT_CLASS_INITIALIZATION_super__failed HOTSPOT_CLASS_INITIALIZATION_SUPER_FAILED 92 #define HOTSPOT_CLASS_INITIALIZATION_clinit HOTSPOT_CLASS_INITIALIZATION_CLINIT 93 #define HOTSPOT_CLASS_INITIALIZATION_error HOTSPOT_CLASS_INITIALIZATION_ERROR 94 #define HOTSPOT_CLASS_INITIALIZATION_end HOTSPOT_CLASS_INITIALIZATION_END 95 #define DTRACE_CLASSINIT_PROBE(type, thread_type) \ 96 { \ 97 char* data = NULL; \ 98 int len = 0; \ 99 Symbol* clss_name = name(); \ 100 if (clss_name != NULL) { \ 101 data = (char*)clss_name->bytes(); \ 102 len = clss_name->utf8_length(); \ 103 } \ 104 HOTSPOT_CLASS_INITIALIZATION_##type( \ 105 data, len, (void*)class_loader(), thread_type); \ 106 } 107 108 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait) \ 109 { \ 110 char* data = NULL; \ 111 int len = 0; \ 112 Symbol* clss_name = name(); \ 113 if (clss_name != NULL) { \ 114 data = (char*)clss_name->bytes(); \ 115 len = clss_name->utf8_length(); \ 116 } \ 117 HOTSPOT_CLASS_INITIALIZATION_##type( \ 118 data, len, (void*)class_loader(), thread_type, wait); \ 119 } 120 121 #else // ndef DTRACE_ENABLED 122 123 #define DTRACE_CLASSINIT_PROBE(type, thread_type) 124 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait) 125 126 #endif // ndef DTRACE_ENABLED 127 128 static inline bool is_class_loader(const Symbol* class_name, 129 const ClassFileParser& parser) { 130 assert(class_name != NULL, "invariant"); 131 132 if (class_name == vmSymbols::java_lang_ClassLoader()) { 133 return true; 134 } 135 136 if (SystemDictionary::ClassLoader_klass_loaded()) { 137 const Klass* const super_klass = parser.super_klass(); 138 if (super_klass != NULL) { 139 if (super_klass->is_subtype_of(SystemDictionary::ClassLoader_klass())) { 140 return true; 141 } 142 } 143 } 144 return false; 145 } 146 147 // called to verify that k is a member of this nest 148 bool InstanceKlass::has_nest_member(InstanceKlass* k, TRAPS) const { 149 if (_nest_members == NULL || _nest_members == Universe::the_empty_short_array()) { 150 if (log_is_enabled(Trace, class, nestmates)) { 151 ResourceMark rm(THREAD); 152 log_trace(class, nestmates)("Checked nest membership of %s in non-nest-host class %s", 153 k->external_name(), this->external_name()); 154 } 155 return false; 156 } 157 158 if (log_is_enabled(Trace, class, nestmates)) { 159 ResourceMark rm(THREAD); 160 log_trace(class, nestmates)("Checking nest membership of %s in %s", 161 k->external_name(), this->external_name()); 162 } 163 164 // Check names first and if they match then check actual klass. This avoids 165 // resolving anything unnecessarily. 166 for (int i = 0; i < _nest_members->length(); i++) { 167 int cp_index = _nest_members->at(i); 168 Symbol* name = _constants->klass_name_at(cp_index); 169 if (name == k->name()) { 170 log_trace(class, nestmates)("- Found it at nest_members[%d] => cp[%d]", i, cp_index); 171 172 // names match so check actual klass - this may trigger class loading if 173 // it doesn't match (but that should be impossible) 174 Klass* k2 = _constants->klass_at(cp_index, CHECK_false); 175 if (k2 == k) { 176 log_trace(class, nestmates)("- class is listed as a nest member"); 177 return true; 178 } else { 179 // same name but different klass! 180 log_trace(class, nestmates)(" - klass comparison failed!"); 181 // can't have different classes for the same name, so we're done 182 return false; 183 } 184 } 185 } 186 log_trace(class, nestmates)("- class is NOT a nest member!"); 187 return false; 188 } 189 190 // Return nest-host class, resolving, validating and saving it if needed. 191 // In cases where this is called from a thread that can not do classloading 192 // (such as a native JIT thread) then we simply return NULL, which in turn 193 // causes the access check to return false. Such code will retry the access 194 // from a more suitable environment later. 195 InstanceKlass* InstanceKlass::nest_host(Symbol* validationException, TRAPS) { 196 InstanceKlass* nest_host_k = _nest_host; 197 if (nest_host_k == NULL) { 198 // need to resolve and save our nest-host class. This could be attempted 199 // concurrently but as the result is idempotent and we don't use the class 200 // then we do not need any synchronization beyond what is implicitly used 201 // during class loading. 202 if (_nest_host_index != 0) { // we have a real nest_host 203 // Before trying to resolve check if we're in a suitable context 204 if (!THREAD->can_call_java() && !_constants->tag_at(_nest_host_index).is_klass()) { 205 if (log_is_enabled(Trace, class, nestmates)) { 206 ResourceMark rm(THREAD); 207 log_trace(class, nestmates)("Rejected resolution of nest-host of %s in unsuitable thread", 208 this->external_name()); 209 } 210 return NULL; 211 } 212 213 if (log_is_enabled(Trace, class, nestmates)) { 214 ResourceMark rm(THREAD); 215 log_trace(class, nestmates)("Resolving nest-host of %s using cp entry for %s", 216 this->external_name(), 217 _constants->klass_name_at(_nest_host_index)->as_C_string()); 218 } 219 220 Klass* k = _constants->klass_at(_nest_host_index, THREAD); 221 if (HAS_PENDING_EXCEPTION) { 222 Handle exc_h = Handle(THREAD, PENDING_EXCEPTION); 223 if (exc_h->is_a(SystemDictionary::NoClassDefFoundError_klass())) { 224 // throw a new CDNFE with the original as its cause, and a clear msg 225 ResourceMark rm(THREAD); 226 char buf[200]; 227 CLEAR_PENDING_EXCEPTION; 228 jio_snprintf(buf, sizeof(buf), 229 "Unable to load nest-host class (%s) of %s", 230 _constants->klass_name_at(_nest_host_index)->as_C_string(), 231 this->external_name()); 232 log_trace(class, nestmates)("%s - NoClassDefFoundError", buf); 233 THROW_MSG_CAUSE_NULL(vmSymbols::java_lang_NoClassDefFoundError(), buf, exc_h); 234 } 235 // All other exceptions pass through (OOME, StackOverflowError, LinkageErrors etc). 236 return NULL; 237 } 238 239 // A valid nest-host is an instance class in the current package that lists this 240 // class as a nest member. If any of these conditions are not met we post the 241 // requested exception type (if any) and return NULL 242 243 const char* error = NULL; 244 245 // JVMS 5.4.4 indicates package check comes first 246 if (is_same_class_package(k)) { 247 248 // Now check actual membership. We can't be a member if our "host" is 249 // not an instance class. 250 if (k->is_instance_klass()) { 251 nest_host_k = InstanceKlass::cast(k); 252 253 bool is_member = nest_host_k->has_nest_member(this, CHECK_NULL); 254 if (is_member) { 255 // save resolved nest-host value 256 _nest_host = nest_host_k; 257 258 if (log_is_enabled(Trace, class, nestmates)) { 259 ResourceMark rm(THREAD); 260 log_trace(class, nestmates)("Resolved nest-host of %s to %s", 261 this->external_name(), k->external_name()); 262 } 263 return nest_host_k; 264 } 265 } 266 error = "current type is not listed as a nest member"; 267 } else { 268 error = "types are in different packages"; 269 } 270 271 if (log_is_enabled(Trace, class, nestmates)) { 272 ResourceMark rm(THREAD); 273 log_trace(class, nestmates)("Type %s is not a nest member of resolved type %s: %s", 274 this->external_name(), 275 k->external_name(), 276 error); 277 } 278 279 if (validationException != NULL) { 280 ResourceMark rm(THREAD); 281 Exceptions::fthrow(THREAD_AND_LOCATION, 282 validationException, 283 "Type %s is not a nest member of %s: %s", 284 this->external_name(), 285 k->external_name(), 286 error 287 ); 288 } 289 return NULL; 290 } else { 291 if (log_is_enabled(Trace, class, nestmates)) { 292 ResourceMark rm(THREAD); 293 log_trace(class, nestmates)("Type %s is not part of a nest: setting nest-host to self", 294 this->external_name()); 295 } 296 // save resolved nest-host value 297 return (_nest_host = this); 298 } 299 } 300 return nest_host_k; 301 } 302 303 // check if 'this' and k are nestmates (same nest_host), or k is our nest_host, 304 // or we are k's nest_host - all of which is covered by comparing the two 305 // resolved_nest_hosts 306 bool InstanceKlass::has_nestmate_access_to(InstanceKlass* k, TRAPS) { 307 308 assert(this != k, "this should be handled by higher-level code"); 309 310 // Per JVMS 5.4.4 we first resolve and validate the current class, then 311 // the target class k. Resolution exceptions will be passed on by upper 312 // layers. IncompatibleClassChangeErrors from membership validation failures 313 // will also be passed through. 314 315 Symbol* icce = vmSymbols::java_lang_IncompatibleClassChangeError(); 316 InstanceKlass* cur_host = nest_host(icce, CHECK_false); 317 if (cur_host == NULL) { 318 return false; 319 } 320 321 Klass* k_nest_host = k->nest_host(icce, CHECK_false); 322 if (k_nest_host == NULL) { 323 return false; 324 } 325 326 bool access = (cur_host == k_nest_host); 327 328 if (log_is_enabled(Trace, class, nestmates)) { 329 ResourceMark rm(THREAD); 330 log_trace(class, nestmates)("Class %s does %shave nestmate access to %s", 331 this->external_name(), 332 access ? "" : "NOT ", 333 k->external_name()); 334 } 335 336 return access; 337 } 338 339 InstanceKlass* InstanceKlass::allocate_instance_klass(const ClassFileParser& parser, TRAPS) { 340 const int size = InstanceKlass::size(parser.vtable_size(), 341 parser.itable_size(), 342 nonstatic_oop_map_size(parser.total_oop_map_count()), 343 parser.is_interface(), 344 parser.is_anonymous(), 345 should_store_fingerprint(parser.is_anonymous())); 346 347 const Symbol* const class_name = parser.class_name(); 348 assert(class_name != NULL, "invariant"); 349 ClassLoaderData* loader_data = parser.loader_data(); 350 assert(loader_data != NULL, "invariant"); 351 352 InstanceKlass* ik; 353 354 // Allocation 355 if (REF_NONE == parser.reference_type()) { 356 if (class_name == vmSymbols::java_lang_Class()) { 357 // mirror 358 ik = new (loader_data, size, THREAD) InstanceMirrorKlass(parser); 359 } 360 else if (is_class_loader(class_name, parser)) { 361 // class loader 362 ik = new (loader_data, size, THREAD) InstanceClassLoaderKlass(parser); 363 } else { 364 // normal 365 ik = new (loader_data, size, THREAD) InstanceKlass(parser, InstanceKlass::_misc_kind_other); 366 } 367 } else { 368 // reference 369 ik = new (loader_data, size, THREAD) InstanceRefKlass(parser); 370 } 371 372 // Check for pending exception before adding to the loader data and incrementing 373 // class count. Can get OOM here. 374 if (HAS_PENDING_EXCEPTION) { 375 return NULL; 376 } 377 378 return ik; 379 } 380 381 382 // copy method ordering from resource area to Metaspace 383 void InstanceKlass::copy_method_ordering(const intArray* m, TRAPS) { 384 if (m != NULL) { 385 // allocate a new array and copy contents (memcpy?) 386 _method_ordering = MetadataFactory::new_array<int>(class_loader_data(), m->length(), CHECK); 387 for (int i = 0; i < m->length(); i++) { 388 _method_ordering->at_put(i, m->at(i)); 389 } 390 } else { 391 _method_ordering = Universe::the_empty_int_array(); 392 } 393 } 394 395 // create a new array of vtable_indices for default methods 396 Array<int>* InstanceKlass::create_new_default_vtable_indices(int len, TRAPS) { 397 Array<int>* vtable_indices = MetadataFactory::new_array<int>(class_loader_data(), len, CHECK_NULL); 398 assert(default_vtable_indices() == NULL, "only create once"); 399 set_default_vtable_indices(vtable_indices); 400 return vtable_indices; 401 } 402 403 InstanceKlass::InstanceKlass(const ClassFileParser& parser, unsigned kind, KlassID id) : 404 Klass(id), 405 _static_field_size(parser.static_field_size()), 406 _nonstatic_oop_map_size(nonstatic_oop_map_size(parser.total_oop_map_count())), 407 _itable_len(parser.itable_size()), 408 _reference_type(parser.reference_type()), 409 _nest_members(NULL), 410 _nest_host_index(0), 411 _nest_host(NULL) { 412 set_vtable_length(parser.vtable_size()); 413 set_kind(kind); 414 set_access_flags(parser.access_flags()); 415 set_is_anonymous(parser.is_anonymous()); 416 set_layout_helper(Klass::instance_layout_helper(parser.layout_size(), 417 false)); 418 419 assert(NULL == _methods, "underlying memory not zeroed?"); 420 assert(is_instance_klass(), "is layout incorrect?"); 421 assert(size_helper() == parser.layout_size(), "incorrect size_helper?"); 422 } 423 424 void InstanceKlass::deallocate_methods(ClassLoaderData* loader_data, 425 Array<Method*>* methods) { 426 if (methods != NULL && methods != Universe::the_empty_method_array() && 427 !methods->is_shared()) { 428 for (int i = 0; i < methods->length(); i++) { 429 Method* method = methods->at(i); 430 if (method == NULL) continue; // maybe null if error processing 431 // Only want to delete methods that are not executing for RedefineClasses. 432 // The previous version will point to them so they're not totally dangling 433 assert (!method->on_stack(), "shouldn't be called with methods on stack"); 434 MetadataFactory::free_metadata(loader_data, method); 435 } 436 MetadataFactory::free_array<Method*>(loader_data, methods); 437 } 438 } 439 440 void InstanceKlass::deallocate_interfaces(ClassLoaderData* loader_data, 441 const Klass* super_klass, 442 Array<Klass*>* local_interfaces, 443 Array<Klass*>* transitive_interfaces) { 444 // Only deallocate transitive interfaces if not empty, same as super class 445 // or same as local interfaces. See code in parseClassFile. 446 Array<Klass*>* ti = transitive_interfaces; 447 if (ti != Universe::the_empty_klass_array() && ti != local_interfaces) { 448 // check that the interfaces don't come from super class 449 Array<Klass*>* sti = (super_klass == NULL) ? NULL : 450 InstanceKlass::cast(super_klass)->transitive_interfaces(); 451 if (ti != sti && ti != NULL && !ti->is_shared()) { 452 MetadataFactory::free_array<Klass*>(loader_data, ti); 453 } 454 } 455 456 // local interfaces can be empty 457 if (local_interfaces != Universe::the_empty_klass_array() && 458 local_interfaces != NULL && !local_interfaces->is_shared()) { 459 MetadataFactory::free_array<Klass*>(loader_data, local_interfaces); 460 } 461 } 462 463 // This function deallocates the metadata and C heap pointers that the 464 // InstanceKlass points to. 465 void InstanceKlass::deallocate_contents(ClassLoaderData* loader_data) { 466 467 // Orphan the mirror first, CMS thinks it's still live. 468 if (java_mirror() != NULL) { 469 java_lang_Class::set_klass(java_mirror(), NULL); 470 } 471 472 // Also remove mirror from handles 473 loader_data->remove_handle(_java_mirror); 474 475 // Need to take this class off the class loader data list. 476 loader_data->remove_class(this); 477 478 // The array_klass for this class is created later, after error handling. 479 // For class redefinition, we keep the original class so this scratch class 480 // doesn't have an array class. Either way, assert that there is nothing 481 // to deallocate. 482 assert(array_klasses() == NULL, "array classes shouldn't be created for this class yet"); 483 484 // Release C heap allocated data that this might point to, which includes 485 // reference counting symbol names. 486 release_C_heap_structures(); 487 488 deallocate_methods(loader_data, methods()); 489 set_methods(NULL); 490 491 if (method_ordering() != NULL && 492 method_ordering() != Universe::the_empty_int_array() && 493 !method_ordering()->is_shared()) { 494 MetadataFactory::free_array<int>(loader_data, method_ordering()); 495 } 496 set_method_ordering(NULL); 497 498 // default methods can be empty 499 if (default_methods() != NULL && 500 default_methods() != Universe::the_empty_method_array() && 501 !default_methods()->is_shared()) { 502 MetadataFactory::free_array<Method*>(loader_data, default_methods()); 503 } 504 // Do NOT deallocate the default methods, they are owned by superinterfaces. 505 set_default_methods(NULL); 506 507 // default methods vtable indices can be empty 508 if (default_vtable_indices() != NULL && 509 !default_vtable_indices()->is_shared()) { 510 MetadataFactory::free_array<int>(loader_data, default_vtable_indices()); 511 } 512 set_default_vtable_indices(NULL); 513 514 515 // This array is in Klass, but remove it with the InstanceKlass since 516 // this place would be the only caller and it can share memory with transitive 517 // interfaces. 518 if (secondary_supers() != NULL && 519 secondary_supers() != Universe::the_empty_klass_array() && 520 secondary_supers() != transitive_interfaces() && 521 !secondary_supers()->is_shared()) { 522 MetadataFactory::free_array<Klass*>(loader_data, secondary_supers()); 523 } 524 set_secondary_supers(NULL); 525 526 deallocate_interfaces(loader_data, super(), local_interfaces(), transitive_interfaces()); 527 set_transitive_interfaces(NULL); 528 set_local_interfaces(NULL); 529 530 if (fields() != NULL && !fields()->is_shared()) { 531 MetadataFactory::free_array<jushort>(loader_data, fields()); 532 } 533 set_fields(NULL, 0); 534 535 // If a method from a redefined class is using this constant pool, don't 536 // delete it, yet. The new class's previous version will point to this. 537 if (constants() != NULL) { 538 assert (!constants()->on_stack(), "shouldn't be called if anything is onstack"); 539 if (!constants()->is_shared()) { 540 MetadataFactory::free_metadata(loader_data, constants()); 541 } 542 // Delete any cached resolution errors for the constant pool 543 SystemDictionary::delete_resolution_error(constants()); 544 545 set_constants(NULL); 546 } 547 548 if (inner_classes() != NULL && 549 inner_classes() != Universe::the_empty_short_array() && 550 !inner_classes()->is_shared()) { 551 MetadataFactory::free_array<jushort>(loader_data, inner_classes()); 552 } 553 set_inner_classes(NULL); 554 555 if (nest_members() != NULL && 556 nest_members() != Universe::the_empty_short_array() && 557 !nest_members()->is_shared()) { 558 MetadataFactory::free_array<jushort>(loader_data, nest_members()); 559 } 560 set_nest_members(NULL); 561 562 // We should deallocate the Annotations instance if it's not in shared spaces. 563 if (annotations() != NULL && !annotations()->is_shared()) { 564 MetadataFactory::free_metadata(loader_data, annotations()); 565 } 566 set_annotations(NULL); 567 } 568 569 bool InstanceKlass::should_be_initialized() const { 570 return !is_initialized(); 571 } 572 573 klassItable InstanceKlass::itable() const { 574 return klassItable(const_cast<InstanceKlass*>(this)); 575 } 576 577 void InstanceKlass::eager_initialize(Thread *thread) { 578 if (!EagerInitialization) return; 579 580 if (this->is_not_initialized()) { 581 // abort if the the class has a class initializer 582 if (this->class_initializer() != NULL) return; 583 584 // abort if it is java.lang.Object (initialization is handled in genesis) 585 Klass* super_klass = super(); 586 if (super_klass == NULL) return; 587 588 // abort if the super class should be initialized 589 if (!InstanceKlass::cast(super_klass)->is_initialized()) return; 590 591 // call body to expose the this pointer 592 eager_initialize_impl(); 593 } 594 } 595 596 // JVMTI spec thinks there are signers and protection domain in the 597 // instanceKlass. These accessors pretend these fields are there. 598 // The hprof specification also thinks these fields are in InstanceKlass. 599 oop InstanceKlass::protection_domain() const { 600 // return the protection_domain from the mirror 601 return java_lang_Class::protection_domain(java_mirror()); 602 } 603 604 // To remove these from requires an incompatible change and CCC request. 605 objArrayOop InstanceKlass::signers() const { 606 // return the signers from the mirror 607 return java_lang_Class::signers(java_mirror()); 608 } 609 610 oop InstanceKlass::init_lock() const { 611 // return the init lock from the mirror 612 oop lock = java_lang_Class::init_lock(java_mirror()); 613 // Prevent reordering with any access of initialization state 614 OrderAccess::loadload(); 615 assert((oop)lock != NULL || !is_not_initialized(), // initialized or in_error state 616 "only fully initialized state can have a null lock"); 617 return lock; 618 } 619 620 // Set the initialization lock to null so the object can be GC'ed. Any racing 621 // threads to get this lock will see a null lock and will not lock. 622 // That's okay because they all check for initialized state after getting 623 // the lock and return. 624 void InstanceKlass::fence_and_clear_init_lock() { 625 // make sure previous stores are all done, notably the init_state. 626 OrderAccess::storestore(); 627 java_lang_Class::set_init_lock(java_mirror(), NULL); 628 assert(!is_not_initialized(), "class must be initialized now"); 629 } 630 631 void InstanceKlass::eager_initialize_impl() { 632 EXCEPTION_MARK; 633 HandleMark hm(THREAD); 634 Handle h_init_lock(THREAD, init_lock()); 635 ObjectLocker ol(h_init_lock, THREAD, h_init_lock() != NULL); 636 637 // abort if someone beat us to the initialization 638 if (!is_not_initialized()) return; // note: not equivalent to is_initialized() 639 640 ClassState old_state = init_state(); 641 link_class_impl(true, THREAD); 642 if (HAS_PENDING_EXCEPTION) { 643 CLEAR_PENDING_EXCEPTION; 644 // Abort if linking the class throws an exception. 645 646 // Use a test to avoid redundantly resetting the state if there's 647 // no change. Set_init_state() asserts that state changes make 648 // progress, whereas here we might just be spinning in place. 649 if (old_state != _init_state) 650 set_init_state(old_state); 651 } else { 652 // linking successfull, mark class as initialized 653 set_init_state(fully_initialized); 654 fence_and_clear_init_lock(); 655 // trace 656 if (log_is_enabled(Info, class, init)) { 657 ResourceMark rm(THREAD); 658 log_info(class, init)("[Initialized %s without side effects]", external_name()); 659 } 660 } 661 } 662 663 664 // See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization 665 // process. The step comments refers to the procedure described in that section. 666 // Note: implementation moved to static method to expose the this pointer. 667 void InstanceKlass::initialize(TRAPS) { 668 if (this->should_be_initialized()) { 669 initialize_impl(CHECK); 670 // Note: at this point the class may be initialized 671 // OR it may be in the state of being initialized 672 // in case of recursive initialization! 673 } else { 674 assert(is_initialized(), "sanity check"); 675 } 676 } 677 678 679 bool InstanceKlass::verify_code(bool throw_verifyerror, TRAPS) { 680 // 1) Verify the bytecodes 681 Verifier::Mode mode = 682 throw_verifyerror ? Verifier::ThrowException : Verifier::NoException; 683 return Verifier::verify(this, mode, should_verify_class(), THREAD); 684 } 685 686 687 // Used exclusively by the shared spaces dump mechanism to prevent 688 // classes mapped into the shared regions in new VMs from appearing linked. 689 690 void InstanceKlass::unlink_class() { 691 assert(is_linked(), "must be linked"); 692 _init_state = loaded; 693 } 694 695 void InstanceKlass::link_class(TRAPS) { 696 assert(is_loaded(), "must be loaded"); 697 if (!is_linked()) { 698 link_class_impl(true, CHECK); 699 } 700 } 701 702 // Called to verify that a class can link during initialization, without 703 // throwing a VerifyError. 704 bool InstanceKlass::link_class_or_fail(TRAPS) { 705 assert(is_loaded(), "must be loaded"); 706 if (!is_linked()) { 707 link_class_impl(false, CHECK_false); 708 } 709 return is_linked(); 710 } 711 712 bool InstanceKlass::link_class_impl(bool throw_verifyerror, TRAPS) { 713 if (DumpSharedSpaces && is_in_error_state()) { 714 // This is for CDS dumping phase only -- we use the in_error_state to indicate that 715 // the class has failed verification. Throwing the NoClassDefFoundError here is just 716 // a convenient way to stop repeat attempts to verify the same (bad) class. 717 // 718 // Note that the NoClassDefFoundError is not part of the JLS, and should not be thrown 719 // if we are executing Java code. This is not a problem for CDS dumping phase since 720 // it doesn't execute any Java code. 721 ResourceMark rm(THREAD); 722 Exceptions::fthrow(THREAD_AND_LOCATION, 723 vmSymbols::java_lang_NoClassDefFoundError(), 724 "Class %s, or one of its supertypes, failed class initialization", 725 external_name()); 726 return false; 727 } 728 // return if already verified 729 if (is_linked()) { 730 return true; 731 } 732 733 // Timing 734 // timer handles recursion 735 assert(THREAD->is_Java_thread(), "non-JavaThread in link_class_impl"); 736 JavaThread* jt = (JavaThread*)THREAD; 737 738 // link super class before linking this class 739 Klass* super_klass = super(); 740 if (super_klass != NULL) { 741 if (super_klass->is_interface()) { // check if super class is an interface 742 ResourceMark rm(THREAD); 743 Exceptions::fthrow( 744 THREAD_AND_LOCATION, 745 vmSymbols::java_lang_IncompatibleClassChangeError(), 746 "class %s has interface %s as super class", 747 external_name(), 748 super_klass->external_name() 749 ); 750 return false; 751 } 752 753 InstanceKlass* ik_super = InstanceKlass::cast(super_klass); 754 ik_super->link_class_impl(throw_verifyerror, CHECK_false); 755 } 756 757 // link all interfaces implemented by this class before linking this class 758 Array<Klass*>* interfaces = local_interfaces(); 759 int num_interfaces = interfaces->length(); 760 for (int index = 0; index < num_interfaces; index++) { 761 InstanceKlass* interk = InstanceKlass::cast(interfaces->at(index)); 762 interk->link_class_impl(throw_verifyerror, CHECK_false); 763 } 764 765 // in case the class is linked in the process of linking its superclasses 766 if (is_linked()) { 767 return true; 768 } 769 770 // trace only the link time for this klass that includes 771 // the verification time 772 PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(), 773 ClassLoader::perf_class_link_selftime(), 774 ClassLoader::perf_classes_linked(), 775 jt->get_thread_stat()->perf_recursion_counts_addr(), 776 jt->get_thread_stat()->perf_timers_addr(), 777 PerfClassTraceTime::CLASS_LINK); 778 779 // verification & rewriting 780 { 781 HandleMark hm(THREAD); 782 Handle h_init_lock(THREAD, init_lock()); 783 ObjectLocker ol(h_init_lock, THREAD, h_init_lock() != NULL); 784 // rewritten will have been set if loader constraint error found 785 // on an earlier link attempt 786 // don't verify or rewrite if already rewritten 787 // 788 789 if (!is_linked()) { 790 if (!is_rewritten()) { 791 { 792 bool verify_ok = verify_code(throw_verifyerror, THREAD); 793 if (!verify_ok) { 794 return false; 795 } 796 } 797 798 // Just in case a side-effect of verify linked this class already 799 // (which can sometimes happen since the verifier loads classes 800 // using custom class loaders, which are free to initialize things) 801 if (is_linked()) { 802 return true; 803 } 804 805 // also sets rewritten 806 rewrite_class(CHECK_false); 807 } else if (is_shared()) { 808 SystemDictionaryShared::check_verification_constraints(this, CHECK_false); 809 } 810 811 // relocate jsrs and link methods after they are all rewritten 812 link_methods(CHECK_false); 813 814 // Initialize the vtable and interface table after 815 // methods have been rewritten since rewrite may 816 // fabricate new Method*s. 817 // also does loader constraint checking 818 // 819 // initialize_vtable and initialize_itable need to be rerun for 820 // a shared class if the class is not loaded by the NULL classloader. 821 ClassLoaderData * loader_data = class_loader_data(); 822 if (!(is_shared() && 823 loader_data->is_the_null_class_loader_data())) { 824 vtable().initialize_vtable(true, CHECK_false); 825 itable().initialize_itable(true, CHECK_false); 826 } 827 #ifdef ASSERT 828 else { 829 vtable().verify(tty, true); 830 // In case itable verification is ever added. 831 // itable().verify(tty, true); 832 } 833 #endif 834 set_init_state(linked); 835 if (JvmtiExport::should_post_class_prepare()) { 836 Thread *thread = THREAD; 837 assert(thread->is_Java_thread(), "thread->is_Java_thread()"); 838 JvmtiExport::post_class_prepare((JavaThread *) thread, this); 839 } 840 } 841 } 842 return true; 843 } 844 845 // Rewrite the byte codes of all of the methods of a class. 846 // The rewriter must be called exactly once. Rewriting must happen after 847 // verification but before the first method of the class is executed. 848 void InstanceKlass::rewrite_class(TRAPS) { 849 assert(is_loaded(), "must be loaded"); 850 if (is_rewritten()) { 851 assert(is_shared(), "rewriting an unshared class?"); 852 return; 853 } 854 Rewriter::rewrite(this, CHECK); 855 set_rewritten(); 856 } 857 858 // Now relocate and link method entry points after class is rewritten. 859 // This is outside is_rewritten flag. In case of an exception, it can be 860 // executed more than once. 861 void InstanceKlass::link_methods(TRAPS) { 862 int len = methods()->length(); 863 for (int i = len-1; i >= 0; i--) { 864 methodHandle m(THREAD, methods()->at(i)); 865 866 // Set up method entry points for compiler and interpreter . 867 m->link_method(m, CHECK); 868 } 869 } 870 871 // Eagerly initialize superinterfaces that declare default methods (concrete instance: any access) 872 void InstanceKlass::initialize_super_interfaces(TRAPS) { 873 assert (has_nonstatic_concrete_methods(), "caller should have checked this"); 874 for (int i = 0; i < local_interfaces()->length(); ++i) { 875 Klass* iface = local_interfaces()->at(i); 876 InstanceKlass* ik = InstanceKlass::cast(iface); 877 878 // Initialization is depth first search ie. we start with top of the inheritance tree 879 // has_nonstatic_concrete_methods drives searching superinterfaces since it 880 // means has_nonstatic_concrete_methods in its superinterface hierarchy 881 if (ik->has_nonstatic_concrete_methods()) { 882 ik->initialize_super_interfaces(CHECK); 883 } 884 885 // Only initialize() interfaces that "declare" concrete methods. 886 if (ik->should_be_initialized() && ik->declares_nonstatic_concrete_methods()) { 887 ik->initialize(CHECK); 888 } 889 } 890 } 891 892 void InstanceKlass::initialize_impl(TRAPS) { 893 HandleMark hm(THREAD); 894 895 // Make sure klass is linked (verified) before initialization 896 // A class could already be verified, since it has been reflected upon. 897 link_class(CHECK); 898 899 DTRACE_CLASSINIT_PROBE(required, -1); 900 901 bool wait = false; 902 903 // refer to the JVM book page 47 for description of steps 904 // Step 1 905 { 906 Handle h_init_lock(THREAD, init_lock()); 907 ObjectLocker ol(h_init_lock, THREAD, h_init_lock() != NULL); 908 909 Thread *self = THREAD; // it's passed the current thread 910 911 // Step 2 912 // If we were to use wait() instead of waitInterruptibly() then 913 // we might end up throwing IE from link/symbol resolution sites 914 // that aren't expected to throw. This would wreak havoc. See 6320309. 915 while(is_being_initialized() && !is_reentrant_initialization(self)) { 916 wait = true; 917 ol.waitUninterruptibly(CHECK); 918 } 919 920 // Step 3 921 if (is_being_initialized() && is_reentrant_initialization(self)) { 922 DTRACE_CLASSINIT_PROBE_WAIT(recursive, -1, wait); 923 return; 924 } 925 926 // Step 4 927 if (is_initialized()) { 928 DTRACE_CLASSINIT_PROBE_WAIT(concurrent, -1, wait); 929 return; 930 } 931 932 // Step 5 933 if (is_in_error_state()) { 934 DTRACE_CLASSINIT_PROBE_WAIT(erroneous, -1, wait); 935 ResourceMark rm(THREAD); 936 const char* desc = "Could not initialize class "; 937 const char* className = external_name(); 938 size_t msglen = strlen(desc) + strlen(className) + 1; 939 char* message = NEW_RESOURCE_ARRAY(char, msglen); 940 if (NULL == message) { 941 // Out of memory: can't create detailed error message 942 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), className); 943 } else { 944 jio_snprintf(message, msglen, "%s%s", desc, className); 945 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), message); 946 } 947 } 948 949 // Step 6 950 set_init_state(being_initialized); 951 set_init_thread(self); 952 } 953 954 // Step 7 955 // Next, if C is a class rather than an interface, initialize it's super class and super 956 // interfaces. 957 if (!is_interface()) { 958 Klass* super_klass = super(); 959 if (super_klass != NULL && super_klass->should_be_initialized()) { 960 super_klass->initialize(THREAD); 961 } 962 // If C implements any interface that declares a non-static, concrete method, 963 // the initialization of C triggers initialization of its super interfaces. 964 // Only need to recurse if has_nonstatic_concrete_methods which includes declaring and 965 // having a superinterface that declares, non-static, concrete methods 966 if (!HAS_PENDING_EXCEPTION && has_nonstatic_concrete_methods()) { 967 initialize_super_interfaces(THREAD); 968 } 969 970 // If any exceptions, complete abruptly, throwing the same exception as above. 971 if (HAS_PENDING_EXCEPTION) { 972 Handle e(THREAD, PENDING_EXCEPTION); 973 CLEAR_PENDING_EXCEPTION; 974 { 975 EXCEPTION_MARK; 976 // Locks object, set state, and notify all waiting threads 977 set_initialization_state_and_notify(initialization_error, THREAD); 978 CLEAR_PENDING_EXCEPTION; 979 } 980 DTRACE_CLASSINIT_PROBE_WAIT(super__failed, -1, wait); 981 THROW_OOP(e()); 982 } 983 } 984 985 986 // Look for aot compiled methods for this klass, including class initializer. 987 AOTLoader::load_for_klass(this, THREAD); 988 989 // Step 8 990 { 991 assert(THREAD->is_Java_thread(), "non-JavaThread in initialize_impl"); 992 JavaThread* jt = (JavaThread*)THREAD; 993 DTRACE_CLASSINIT_PROBE_WAIT(clinit, -1, wait); 994 // Timer includes any side effects of class initialization (resolution, 995 // etc), but not recursive entry into call_class_initializer(). 996 PerfClassTraceTime timer(ClassLoader::perf_class_init_time(), 997 ClassLoader::perf_class_init_selftime(), 998 ClassLoader::perf_classes_inited(), 999 jt->get_thread_stat()->perf_recursion_counts_addr(), 1000 jt->get_thread_stat()->perf_timers_addr(), 1001 PerfClassTraceTime::CLASS_CLINIT); 1002 call_class_initializer(THREAD); 1003 } 1004 1005 // Step 9 1006 if (!HAS_PENDING_EXCEPTION) { 1007 set_initialization_state_and_notify(fully_initialized, CHECK); 1008 { 1009 debug_only(vtable().verify(tty, true);) 1010 } 1011 } 1012 else { 1013 // Step 10 and 11 1014 Handle e(THREAD, PENDING_EXCEPTION); 1015 CLEAR_PENDING_EXCEPTION; 1016 // JVMTI has already reported the pending exception 1017 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError 1018 JvmtiExport::clear_detected_exception((JavaThread*)THREAD); 1019 { 1020 EXCEPTION_MARK; 1021 set_initialization_state_and_notify(initialization_error, THREAD); 1022 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, class initialization error is thrown below 1023 // JVMTI has already reported the pending exception 1024 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError 1025 JvmtiExport::clear_detected_exception((JavaThread*)THREAD); 1026 } 1027 DTRACE_CLASSINIT_PROBE_WAIT(error, -1, wait); 1028 if (e->is_a(SystemDictionary::Error_klass())) { 1029 THROW_OOP(e()); 1030 } else { 1031 JavaCallArguments args(e); 1032 THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(), 1033 vmSymbols::throwable_void_signature(), 1034 &args); 1035 } 1036 } 1037 DTRACE_CLASSINIT_PROBE_WAIT(end, -1, wait); 1038 } 1039 1040 1041 void InstanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) { 1042 Handle h_init_lock(THREAD, init_lock()); 1043 if (h_init_lock() != NULL) { 1044 ObjectLocker ol(h_init_lock, THREAD); 1045 set_init_state(state); 1046 fence_and_clear_init_lock(); 1047 ol.notify_all(CHECK); 1048 } else { 1049 assert(h_init_lock() != NULL, "The initialization state should never be set twice"); 1050 set_init_state(state); 1051 } 1052 } 1053 1054 // The embedded _implementor field can only record one implementor. 1055 // When there are more than one implementors, the _implementor field 1056 // is set to the interface Klass* itself. Following are the possible 1057 // values for the _implementor field: 1058 // NULL - no implementor 1059 // implementor Klass* - one implementor 1060 // self - more than one implementor 1061 // 1062 // The _implementor field only exists for interfaces. 1063 void InstanceKlass::add_implementor(Klass* k) { 1064 assert(Compile_lock->owned_by_self(), ""); 1065 assert(is_interface(), "not interface"); 1066 // Filter out my subinterfaces. 1067 // (Note: Interfaces are never on the subklass list.) 1068 if (InstanceKlass::cast(k)->is_interface()) return; 1069 1070 // Filter out subclasses whose supers already implement me. 1071 // (Note: CHA must walk subclasses of direct implementors 1072 // in order to locate indirect implementors.) 1073 Klass* sk = k->super(); 1074 if (sk != NULL && InstanceKlass::cast(sk)->implements_interface(this)) 1075 // We only need to check one immediate superclass, since the 1076 // implements_interface query looks at transitive_interfaces. 1077 // Any supers of the super have the same (or fewer) transitive_interfaces. 1078 return; 1079 1080 Klass* ik = implementor(); 1081 if (ik == NULL) { 1082 set_implementor(k); 1083 } else if (ik != this) { 1084 // There is already an implementor. Use itself as an indicator of 1085 // more than one implementors. 1086 set_implementor(this); 1087 } 1088 1089 // The implementor also implements the transitive_interfaces 1090 for (int index = 0; index < local_interfaces()->length(); index++) { 1091 InstanceKlass::cast(local_interfaces()->at(index))->add_implementor(k); 1092 } 1093 } 1094 1095 void InstanceKlass::init_implementor() { 1096 if (is_interface()) { 1097 set_implementor(NULL); 1098 } 1099 } 1100 1101 1102 void InstanceKlass::process_interfaces(Thread *thread) { 1103 // link this class into the implementors list of every interface it implements 1104 for (int i = local_interfaces()->length() - 1; i >= 0; i--) { 1105 assert(local_interfaces()->at(i)->is_klass(), "must be a klass"); 1106 InstanceKlass* interf = InstanceKlass::cast(local_interfaces()->at(i)); 1107 assert(interf->is_interface(), "expected interface"); 1108 interf->add_implementor(this); 1109 } 1110 } 1111 1112 bool InstanceKlass::can_be_primary_super_slow() const { 1113 if (is_interface()) 1114 return false; 1115 else 1116 return Klass::can_be_primary_super_slow(); 1117 } 1118 1119 GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots, 1120 Array<Klass*>* transitive_interfaces) { 1121 // The secondaries are the implemented interfaces. 1122 Array<Klass*>* interfaces = transitive_interfaces; 1123 int num_secondaries = num_extra_slots + interfaces->length(); 1124 if (num_secondaries == 0) { 1125 // Must share this for correct bootstrapping! 1126 set_secondary_supers(Universe::the_empty_klass_array()); 1127 return NULL; 1128 } else if (num_extra_slots == 0) { 1129 // The secondary super list is exactly the same as the transitive interfaces. 1130 // Redefine classes has to be careful not to delete this! 1131 set_secondary_supers(interfaces); 1132 return NULL; 1133 } else { 1134 // Copy transitive interfaces to a temporary growable array to be constructed 1135 // into the secondary super list with extra slots. 1136 GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length()); 1137 for (int i = 0; i < interfaces->length(); i++) { 1138 secondaries->push(interfaces->at(i)); 1139 } 1140 return secondaries; 1141 } 1142 } 1143 1144 bool InstanceKlass::compute_is_subtype_of(Klass* k) { 1145 if (k->is_interface()) { 1146 return implements_interface(k); 1147 } else { 1148 return Klass::compute_is_subtype_of(k); 1149 } 1150 } 1151 1152 bool InstanceKlass::implements_interface(Klass* k) const { 1153 if (this == k) return true; 1154 assert(k->is_interface(), "should be an interface class"); 1155 for (int i = 0; i < transitive_interfaces()->length(); i++) { 1156 if (transitive_interfaces()->at(i) == k) { 1157 return true; 1158 } 1159 } 1160 return false; 1161 } 1162 1163 bool InstanceKlass::is_same_or_direct_interface(Klass *k) const { 1164 // Verify direct super interface 1165 if (this == k) return true; 1166 assert(k->is_interface(), "should be an interface class"); 1167 for (int i = 0; i < local_interfaces()->length(); i++) { 1168 if (local_interfaces()->at(i) == k) { 1169 return true; 1170 } 1171 } 1172 return false; 1173 } 1174 1175 objArrayOop InstanceKlass::allocate_objArray(int n, int length, TRAPS) { 1176 if (length < 0) { 1177 THROW_MSG_0(vmSymbols::java_lang_NegativeArraySizeException(), err_msg("%d", length)); 1178 } 1179 if (length > arrayOopDesc::max_array_length(T_OBJECT)) { 1180 report_java_out_of_memory("Requested array size exceeds VM limit"); 1181 JvmtiExport::post_array_size_exhausted(); 1182 THROW_OOP_0(Universe::out_of_memory_error_array_size()); 1183 } 1184 int size = objArrayOopDesc::object_size(length); 1185 Klass* ak = array_klass(n, CHECK_NULL); 1186 objArrayOop o = (objArrayOop)Universe::heap()->array_allocate(ak, size, length, 1187 /* do_zero */ true, CHECK_NULL); 1188 return o; 1189 } 1190 1191 instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) { 1192 if (TraceFinalizerRegistration) { 1193 tty->print("Registered "); 1194 i->print_value_on(tty); 1195 tty->print_cr(" (" INTPTR_FORMAT ") as finalizable", p2i(i)); 1196 } 1197 instanceHandle h_i(THREAD, i); 1198 // Pass the handle as argument, JavaCalls::call expects oop as jobjects 1199 JavaValue result(T_VOID); 1200 JavaCallArguments args(h_i); 1201 methodHandle mh (THREAD, Universe::finalizer_register_method()); 1202 JavaCalls::call(&result, mh, &args, CHECK_NULL); 1203 return h_i(); 1204 } 1205 1206 instanceOop InstanceKlass::allocate_instance(TRAPS) { 1207 bool has_finalizer_flag = has_finalizer(); // Query before possible GC 1208 int size = size_helper(); // Query before forming handle. 1209 1210 instanceOop i; 1211 1212 i = (instanceOop)Universe::heap()->obj_allocate(this, size, CHECK_NULL); 1213 if (has_finalizer_flag && !RegisterFinalizersAtInit) { 1214 i = register_finalizer(i, CHECK_NULL); 1215 } 1216 return i; 1217 } 1218 1219 instanceHandle InstanceKlass::allocate_instance_handle(TRAPS) { 1220 return instanceHandle(THREAD, allocate_instance(THREAD)); 1221 } 1222 1223 void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) { 1224 if (is_interface() || is_abstract()) { 1225 ResourceMark rm(THREAD); 1226 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError() 1227 : vmSymbols::java_lang_InstantiationException(), external_name()); 1228 } 1229 if (this == SystemDictionary::Class_klass()) { 1230 ResourceMark rm(THREAD); 1231 THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError() 1232 : vmSymbols::java_lang_IllegalAccessException(), external_name()); 1233 } 1234 } 1235 1236 Klass* InstanceKlass::array_klass_impl(bool or_null, int n, TRAPS) { 1237 // Need load-acquire for lock-free read 1238 if (array_klasses_acquire() == NULL) { 1239 if (or_null) return NULL; 1240 1241 ResourceMark rm; 1242 JavaThread *jt = (JavaThread *)THREAD; 1243 { 1244 // Atomic creation of array_klasses 1245 MutexLocker mc(Compile_lock, THREAD); // for vtables 1246 MutexLocker ma(MultiArray_lock, THREAD); 1247 1248 // Check if update has already taken place 1249 if (array_klasses() == NULL) { 1250 Klass* k = ObjArrayKlass::allocate_objArray_klass(class_loader_data(), 1, this, CHECK_NULL); 1251 // use 'release' to pair with lock-free load 1252 release_set_array_klasses(k); 1253 } 1254 } 1255 } 1256 // _this will always be set at this point 1257 ObjArrayKlass* oak = (ObjArrayKlass*)array_klasses(); 1258 if (or_null) { 1259 return oak->array_klass_or_null(n); 1260 } 1261 return oak->array_klass(n, THREAD); 1262 } 1263 1264 Klass* InstanceKlass::array_klass_impl(bool or_null, TRAPS) { 1265 return array_klass_impl(or_null, 1, THREAD); 1266 } 1267 1268 static int call_class_initializer_counter = 0; // for debugging 1269 1270 Method* InstanceKlass::class_initializer() const { 1271 Method* clinit = find_method( 1272 vmSymbols::class_initializer_name(), vmSymbols::void_method_signature()); 1273 if (clinit != NULL && clinit->has_valid_initializer_flags()) { 1274 return clinit; 1275 } 1276 return NULL; 1277 } 1278 1279 void InstanceKlass::call_class_initializer(TRAPS) { 1280 if (ReplayCompiles && 1281 (ReplaySuppressInitializers == 1 || 1282 (ReplaySuppressInitializers >= 2 && class_loader() != NULL))) { 1283 // Hide the existence of the initializer for the purpose of replaying the compile 1284 return; 1285 } 1286 1287 methodHandle h_method(THREAD, class_initializer()); 1288 assert(!is_initialized(), "we cannot initialize twice"); 1289 LogTarget(Info, class, init) lt; 1290 if (lt.is_enabled()) { 1291 ResourceMark rm; 1292 LogStream ls(lt); 1293 ls.print("%d Initializing ", call_class_initializer_counter++); 1294 name()->print_value_on(&ls); 1295 ls.print_cr("%s (" INTPTR_FORMAT ")", h_method() == NULL ? "(no method)" : "", p2i(this)); 1296 } 1297 if (h_method() != NULL) { 1298 JavaCallArguments args; // No arguments 1299 JavaValue result(T_VOID); 1300 JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args) 1301 } 1302 } 1303 1304 1305 void InstanceKlass::mask_for(const methodHandle& method, int bci, 1306 InterpreterOopMap* entry_for) { 1307 // Lazily create the _oop_map_cache at first request 1308 // Lock-free access requires load_acquire. 1309 OopMapCache* oop_map_cache = OrderAccess::load_acquire(&_oop_map_cache); 1310 if (oop_map_cache == NULL) { 1311 MutexLocker x(OopMapCacheAlloc_lock); 1312 // Check if _oop_map_cache was allocated while we were waiting for this lock 1313 if ((oop_map_cache = _oop_map_cache) == NULL) { 1314 oop_map_cache = new OopMapCache(); 1315 // Ensure _oop_map_cache is stable, since it is examined without a lock 1316 OrderAccess::release_store(&_oop_map_cache, oop_map_cache); 1317 } 1318 } 1319 // _oop_map_cache is constant after init; lookup below does its own locking. 1320 oop_map_cache->lookup(method, bci, entry_for); 1321 } 1322 1323 1324 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const { 1325 for (JavaFieldStream fs(this); !fs.done(); fs.next()) { 1326 Symbol* f_name = fs.name(); 1327 Symbol* f_sig = fs.signature(); 1328 if (f_name == name && f_sig == sig) { 1329 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index()); 1330 return true; 1331 } 1332 } 1333 return false; 1334 } 1335 1336 1337 Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const { 1338 const int n = local_interfaces()->length(); 1339 for (int i = 0; i < n; i++) { 1340 Klass* intf1 = local_interfaces()->at(i); 1341 assert(intf1->is_interface(), "just checking type"); 1342 // search for field in current interface 1343 if (InstanceKlass::cast(intf1)->find_local_field(name, sig, fd)) { 1344 assert(fd->is_static(), "interface field must be static"); 1345 return intf1; 1346 } 1347 // search for field in direct superinterfaces 1348 Klass* intf2 = InstanceKlass::cast(intf1)->find_interface_field(name, sig, fd); 1349 if (intf2 != NULL) return intf2; 1350 } 1351 // otherwise field lookup fails 1352 return NULL; 1353 } 1354 1355 1356 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const { 1357 // search order according to newest JVM spec (5.4.3.2, p.167). 1358 // 1) search for field in current klass 1359 if (find_local_field(name, sig, fd)) { 1360 return const_cast<InstanceKlass*>(this); 1361 } 1362 // 2) search for field recursively in direct superinterfaces 1363 { Klass* intf = find_interface_field(name, sig, fd); 1364 if (intf != NULL) return intf; 1365 } 1366 // 3) apply field lookup recursively if superclass exists 1367 { Klass* supr = super(); 1368 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, fd); 1369 } 1370 // 4) otherwise field lookup fails 1371 return NULL; 1372 } 1373 1374 1375 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const { 1376 // search order according to newest JVM spec (5.4.3.2, p.167). 1377 // 1) search for field in current klass 1378 if (find_local_field(name, sig, fd)) { 1379 if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this); 1380 } 1381 // 2) search for field recursively in direct superinterfaces 1382 if (is_static) { 1383 Klass* intf = find_interface_field(name, sig, fd); 1384 if (intf != NULL) return intf; 1385 } 1386 // 3) apply field lookup recursively if superclass exists 1387 { Klass* supr = super(); 1388 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, is_static, fd); 1389 } 1390 // 4) otherwise field lookup fails 1391 return NULL; 1392 } 1393 1394 1395 bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const { 1396 for (JavaFieldStream fs(this); !fs.done(); fs.next()) { 1397 if (fs.offset() == offset) { 1398 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index()); 1399 if (fd->is_static() == is_static) return true; 1400 } 1401 } 1402 return false; 1403 } 1404 1405 1406 bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const { 1407 Klass* klass = const_cast<InstanceKlass*>(this); 1408 while (klass != NULL) { 1409 if (InstanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) { 1410 return true; 1411 } 1412 klass = klass->super(); 1413 } 1414 return false; 1415 } 1416 1417 1418 void InstanceKlass::methods_do(void f(Method* method)) { 1419 // Methods aren't stable until they are loaded. This can be read outside 1420 // a lock through the ClassLoaderData for profiling 1421 if (!is_loaded()) { 1422 return; 1423 } 1424 1425 int len = methods()->length(); 1426 for (int index = 0; index < len; index++) { 1427 Method* m = methods()->at(index); 1428 assert(m->is_method(), "must be method"); 1429 f(m); 1430 } 1431 } 1432 1433 1434 void InstanceKlass::do_local_static_fields(FieldClosure* cl) { 1435 for (JavaFieldStream fs(this); !fs.done(); fs.next()) { 1436 if (fs.access_flags().is_static()) { 1437 fieldDescriptor& fd = fs.field_descriptor(); 1438 cl->do_field(&fd); 1439 } 1440 } 1441 } 1442 1443 1444 void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle mirror, TRAPS) { 1445 for (JavaFieldStream fs(this); !fs.done(); fs.next()) { 1446 if (fs.access_flags().is_static()) { 1447 fieldDescriptor& fd = fs.field_descriptor(); 1448 f(&fd, mirror, CHECK); 1449 } 1450 } 1451 } 1452 1453 1454 static int compare_fields_by_offset(int* a, int* b) { 1455 return a[0] - b[0]; 1456 } 1457 1458 void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) { 1459 InstanceKlass* super = superklass(); 1460 if (super != NULL) { 1461 super->do_nonstatic_fields(cl); 1462 } 1463 fieldDescriptor fd; 1464 int length = java_fields_count(); 1465 // In DebugInfo nonstatic fields are sorted by offset. 1466 int* fields_sorted = NEW_C_HEAP_ARRAY(int, 2*(length+1), mtClass); 1467 int j = 0; 1468 for (int i = 0; i < length; i += 1) { 1469 fd.reinitialize(this, i); 1470 if (!fd.is_static()) { 1471 fields_sorted[j + 0] = fd.offset(); 1472 fields_sorted[j + 1] = i; 1473 j += 2; 1474 } 1475 } 1476 if (j > 0) { 1477 length = j; 1478 // _sort_Fn is defined in growableArray.hpp. 1479 qsort(fields_sorted, length/2, 2*sizeof(int), (_sort_Fn)compare_fields_by_offset); 1480 for (int i = 0; i < length; i += 2) { 1481 fd.reinitialize(this, fields_sorted[i + 1]); 1482 assert(!fd.is_static() && fd.offset() == fields_sorted[i], "only nonstatic fields"); 1483 cl->do_field(&fd); 1484 } 1485 } 1486 FREE_C_HEAP_ARRAY(int, fields_sorted); 1487 } 1488 1489 1490 void InstanceKlass::array_klasses_do(void f(Klass* k, TRAPS), TRAPS) { 1491 if (array_klasses() != NULL) 1492 ArrayKlass::cast(array_klasses())->array_klasses_do(f, THREAD); 1493 } 1494 1495 void InstanceKlass::array_klasses_do(void f(Klass* k)) { 1496 if (array_klasses() != NULL) 1497 ArrayKlass::cast(array_klasses())->array_klasses_do(f); 1498 } 1499 1500 #ifdef ASSERT 1501 static int linear_search(const Array<Method*>* methods, 1502 const Symbol* name, 1503 const Symbol* signature) { 1504 const int len = methods->length(); 1505 for (int index = 0; index < len; index++) { 1506 const Method* const m = methods->at(index); 1507 assert(m->is_method(), "must be method"); 1508 if (m->signature() == signature && m->name() == name) { 1509 return index; 1510 } 1511 } 1512 return -1; 1513 } 1514 #endif 1515 1516 static int binary_search(const Array<Method*>* methods, const Symbol* name) { 1517 int len = methods->length(); 1518 // methods are sorted, so do binary search 1519 int l = 0; 1520 int h = len - 1; 1521 while (l <= h) { 1522 int mid = (l + h) >> 1; 1523 Method* m = methods->at(mid); 1524 assert(m->is_method(), "must be method"); 1525 int res = m->name()->fast_compare(name); 1526 if (res == 0) { 1527 return mid; 1528 } else if (res < 0) { 1529 l = mid + 1; 1530 } else { 1531 h = mid - 1; 1532 } 1533 } 1534 return -1; 1535 } 1536 1537 // find_method looks up the name/signature in the local methods array 1538 Method* InstanceKlass::find_method(const Symbol* name, 1539 const Symbol* signature) const { 1540 return find_method_impl(name, signature, find_overpass, find_static, find_private); 1541 } 1542 1543 Method* InstanceKlass::find_method_impl(const Symbol* name, 1544 const Symbol* signature, 1545 OverpassLookupMode overpass_mode, 1546 StaticLookupMode static_mode, 1547 PrivateLookupMode private_mode) const { 1548 return InstanceKlass::find_method_impl(methods(), 1549 name, 1550 signature, 1551 overpass_mode, 1552 static_mode, 1553 private_mode); 1554 } 1555 1556 // find_instance_method looks up the name/signature in the local methods array 1557 // and skips over static methods 1558 Method* InstanceKlass::find_instance_method(const Array<Method*>* methods, 1559 const Symbol* name, 1560 const Symbol* signature, 1561 PrivateLookupMode private_mode) { 1562 Method* const meth = InstanceKlass::find_method_impl(methods, 1563 name, 1564 signature, 1565 find_overpass, 1566 skip_static, 1567 private_mode); 1568 assert(((meth == NULL) || !meth->is_static()), 1569 "find_instance_method should have skipped statics"); 1570 return meth; 1571 } 1572 1573 // find_instance_method looks up the name/signature in the local methods array 1574 // and skips over static methods 1575 Method* InstanceKlass::find_instance_method(const Symbol* name, 1576 const Symbol* signature, 1577 PrivateLookupMode private_mode) const { 1578 return InstanceKlass::find_instance_method(methods(), name, signature, private_mode); 1579 } 1580 1581 // Find looks up the name/signature in the local methods array 1582 // and filters on the overpass, static and private flags 1583 // This returns the first one found 1584 // note that the local methods array can have up to one overpass, one static 1585 // and one instance (private or not) with the same name/signature 1586 Method* InstanceKlass::find_local_method(const Symbol* name, 1587 const Symbol* signature, 1588 OverpassLookupMode overpass_mode, 1589 StaticLookupMode static_mode, 1590 PrivateLookupMode private_mode) const { 1591 return InstanceKlass::find_method_impl(methods(), 1592 name, 1593 signature, 1594 overpass_mode, 1595 static_mode, 1596 private_mode); 1597 } 1598 1599 // Find looks up the name/signature in the local methods array 1600 // and filters on the overpass, static and private flags 1601 // This returns the first one found 1602 // note that the local methods array can have up to one overpass, one static 1603 // and one instance (private or not) with the same name/signature 1604 Method* InstanceKlass::find_local_method(const Array<Method*>* methods, 1605 const Symbol* name, 1606 const Symbol* signature, 1607 OverpassLookupMode overpass_mode, 1608 StaticLookupMode static_mode, 1609 PrivateLookupMode private_mode) { 1610 return InstanceKlass::find_method_impl(methods, 1611 name, 1612 signature, 1613 overpass_mode, 1614 static_mode, 1615 private_mode); 1616 } 1617 1618 Method* InstanceKlass::find_method(const Array<Method*>* methods, 1619 const Symbol* name, 1620 const Symbol* signature) { 1621 return InstanceKlass::find_method_impl(methods, 1622 name, 1623 signature, 1624 find_overpass, 1625 find_static, 1626 find_private); 1627 } 1628 1629 Method* InstanceKlass::find_method_impl(const Array<Method*>* methods, 1630 const Symbol* name, 1631 const Symbol* signature, 1632 OverpassLookupMode overpass_mode, 1633 StaticLookupMode static_mode, 1634 PrivateLookupMode private_mode) { 1635 int hit = find_method_index(methods, name, signature, overpass_mode, static_mode, private_mode); 1636 return hit >= 0 ? methods->at(hit): NULL; 1637 } 1638 1639 // true if method matches signature and conforms to skipping_X conditions. 1640 static bool method_matches(const Method* m, 1641 const Symbol* signature, 1642 bool skipping_overpass, 1643 bool skipping_static, 1644 bool skipping_private) { 1645 return ((m->signature() == signature) && 1646 (!skipping_overpass || !m->is_overpass()) && 1647 (!skipping_static || !m->is_static()) && 1648 (!skipping_private || !m->is_private())); 1649 } 1650 1651 // Used directly for default_methods to find the index into the 1652 // default_vtable_indices, and indirectly by find_method 1653 // find_method_index looks in the local methods array to return the index 1654 // of the matching name/signature. If, overpass methods are being ignored, 1655 // the search continues to find a potential non-overpass match. This capability 1656 // is important during method resolution to prefer a static method, for example, 1657 // over an overpass method. 1658 // There is the possibility in any _method's array to have the same name/signature 1659 // for a static method, an overpass method and a local instance method 1660 // To correctly catch a given method, the search criteria may need 1661 // to explicitly skip the other two. For local instance methods, it 1662 // is often necessary to skip private methods 1663 int InstanceKlass::find_method_index(const Array<Method*>* methods, 1664 const Symbol* name, 1665 const Symbol* signature, 1666 OverpassLookupMode overpass_mode, 1667 StaticLookupMode static_mode, 1668 PrivateLookupMode private_mode) { 1669 const bool skipping_overpass = (overpass_mode == skip_overpass); 1670 const bool skipping_static = (static_mode == skip_static); 1671 const bool skipping_private = (private_mode == skip_private); 1672 const int hit = binary_search(methods, name); 1673 if (hit != -1) { 1674 const Method* const m = methods->at(hit); 1675 1676 // Do linear search to find matching signature. First, quick check 1677 // for common case, ignoring overpasses if requested. 1678 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) { 1679 return hit; 1680 } 1681 1682 // search downwards through overloaded methods 1683 int i; 1684 for (i = hit - 1; i >= 0; --i) { 1685 const Method* const m = methods->at(i); 1686 assert(m->is_method(), "must be method"); 1687 if (m->name() != name) { 1688 break; 1689 } 1690 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) { 1691 return i; 1692 } 1693 } 1694 // search upwards 1695 for (i = hit + 1; i < methods->length(); ++i) { 1696 const Method* const m = methods->at(i); 1697 assert(m->is_method(), "must be method"); 1698 if (m->name() != name) { 1699 break; 1700 } 1701 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) { 1702 return i; 1703 } 1704 } 1705 // not found 1706 #ifdef ASSERT 1707 const int index = (skipping_overpass || skipping_static || skipping_private) ? -1 : 1708 linear_search(methods, name, signature); 1709 assert(-1 == index, "binary search should have found entry %d", index); 1710 #endif 1711 } 1712 return -1; 1713 } 1714 1715 int InstanceKlass::find_method_by_name(const Symbol* name, int* end) const { 1716 return find_method_by_name(methods(), name, end); 1717 } 1718 1719 int InstanceKlass::find_method_by_name(const Array<Method*>* methods, 1720 const Symbol* name, 1721 int* end_ptr) { 1722 assert(end_ptr != NULL, "just checking"); 1723 int start = binary_search(methods, name); 1724 int end = start + 1; 1725 if (start != -1) { 1726 while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start; 1727 while (end < methods->length() && (methods->at(end))->name() == name) ++end; 1728 *end_ptr = end; 1729 return start; 1730 } 1731 return -1; 1732 } 1733 1734 // uncached_lookup_method searches both the local class methods array and all 1735 // superclasses methods arrays, skipping any overpass methods in superclasses, 1736 // and possibly skipping private methods. 1737 Method* InstanceKlass::uncached_lookup_method(const Symbol* name, 1738 const Symbol* signature, 1739 OverpassLookupMode overpass_mode, 1740 PrivateLookupMode private_mode) const { 1741 OverpassLookupMode overpass_local_mode = overpass_mode; 1742 const Klass* klass = this; 1743 while (klass != NULL) { 1744 Method* const method = InstanceKlass::cast(klass)->find_method_impl(name, 1745 signature, 1746 overpass_local_mode, 1747 find_static, 1748 private_mode); 1749 if (method != NULL) { 1750 return method; 1751 } 1752 klass = klass->super(); 1753 overpass_local_mode = skip_overpass; // Always ignore overpass methods in superclasses 1754 } 1755 return NULL; 1756 } 1757 1758 #ifdef ASSERT 1759 // search through class hierarchy and return true if this class or 1760 // one of the superclasses was redefined 1761 bool InstanceKlass::has_redefined_this_or_super() const { 1762 const Klass* klass = this; 1763 while (klass != NULL) { 1764 if (InstanceKlass::cast(klass)->has_been_redefined()) { 1765 return true; 1766 } 1767 klass = klass->super(); 1768 } 1769 return false; 1770 } 1771 #endif 1772 1773 // lookup a method in the default methods list then in all transitive interfaces 1774 // Do NOT return private or static methods 1775 Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name, 1776 Symbol* signature) const { 1777 Method* m = NULL; 1778 if (default_methods() != NULL) { 1779 m = find_method(default_methods(), name, signature); 1780 } 1781 // Look up interfaces 1782 if (m == NULL) { 1783 m = lookup_method_in_all_interfaces(name, signature, find_defaults); 1784 } 1785 return m; 1786 } 1787 1788 // lookup a method in all the interfaces that this class implements 1789 // Do NOT return private or static methods, new in JDK8 which are not externally visible 1790 // They should only be found in the initial InterfaceMethodRef 1791 Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name, 1792 Symbol* signature, 1793 DefaultsLookupMode defaults_mode) const { 1794 Array<Klass*>* all_ifs = transitive_interfaces(); 1795 int num_ifs = all_ifs->length(); 1796 InstanceKlass *ik = NULL; 1797 for (int i = 0; i < num_ifs; i++) { 1798 ik = InstanceKlass::cast(all_ifs->at(i)); 1799 Method* m = ik->lookup_method(name, signature); 1800 if (m != NULL && m->is_public() && !m->is_static() && 1801 ((defaults_mode != skip_defaults) || !m->is_default_method())) { 1802 return m; 1803 } 1804 } 1805 return NULL; 1806 } 1807 1808 /* jni_id_for_impl for jfieldIds only */ 1809 JNIid* InstanceKlass::jni_id_for_impl(int offset) { 1810 MutexLocker ml(JfieldIdCreation_lock); 1811 // Retry lookup after we got the lock 1812 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset); 1813 if (probe == NULL) { 1814 // Slow case, allocate new static field identifier 1815 probe = new JNIid(this, offset, jni_ids()); 1816 set_jni_ids(probe); 1817 } 1818 return probe; 1819 } 1820 1821 1822 /* jni_id_for for jfieldIds only */ 1823 JNIid* InstanceKlass::jni_id_for(int offset) { 1824 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset); 1825 if (probe == NULL) { 1826 probe = jni_id_for_impl(offset); 1827 } 1828 return probe; 1829 } 1830 1831 u2 InstanceKlass::enclosing_method_data(int offset) const { 1832 const Array<jushort>* const inner_class_list = inner_classes(); 1833 if (inner_class_list == NULL) { 1834 return 0; 1835 } 1836 const int length = inner_class_list->length(); 1837 if (length % inner_class_next_offset == 0) { 1838 return 0; 1839 } 1840 const int index = length - enclosing_method_attribute_size; 1841 assert(offset < enclosing_method_attribute_size, "invalid offset"); 1842 return inner_class_list->at(index + offset); 1843 } 1844 1845 void InstanceKlass::set_enclosing_method_indices(u2 class_index, 1846 u2 method_index) { 1847 Array<jushort>* inner_class_list = inner_classes(); 1848 assert (inner_class_list != NULL, "_inner_classes list is not set up"); 1849 int length = inner_class_list->length(); 1850 if (length % inner_class_next_offset == enclosing_method_attribute_size) { 1851 int index = length - enclosing_method_attribute_size; 1852 inner_class_list->at_put( 1853 index + enclosing_method_class_index_offset, class_index); 1854 inner_class_list->at_put( 1855 index + enclosing_method_method_index_offset, method_index); 1856 } 1857 } 1858 1859 // Lookup or create a jmethodID. 1860 // This code is called by the VMThread and JavaThreads so the 1861 // locking has to be done very carefully to avoid deadlocks 1862 // and/or other cache consistency problems. 1863 // 1864 jmethodID InstanceKlass::get_jmethod_id(const methodHandle& method_h) { 1865 size_t idnum = (size_t)method_h->method_idnum(); 1866 jmethodID* jmeths = methods_jmethod_ids_acquire(); 1867 size_t length = 0; 1868 jmethodID id = NULL; 1869 1870 // We use a double-check locking idiom here because this cache is 1871 // performance sensitive. In the normal system, this cache only 1872 // transitions from NULL to non-NULL which is safe because we use 1873 // release_set_methods_jmethod_ids() to advertise the new cache. 1874 // A partially constructed cache should never be seen by a racing 1875 // thread. We also use release_store() to save a new jmethodID 1876 // in the cache so a partially constructed jmethodID should never be 1877 // seen either. Cache reads of existing jmethodIDs proceed without a 1878 // lock, but cache writes of a new jmethodID requires uniqueness and 1879 // creation of the cache itself requires no leaks so a lock is 1880 // generally acquired in those two cases. 1881 // 1882 // If the RedefineClasses() API has been used, then this cache can 1883 // grow and we'll have transitions from non-NULL to bigger non-NULL. 1884 // Cache creation requires no leaks and we require safety between all 1885 // cache accesses and freeing of the old cache so a lock is generally 1886 // acquired when the RedefineClasses() API has been used. 1887 1888 if (jmeths != NULL) { 1889 // the cache already exists 1890 if (!idnum_can_increment()) { 1891 // the cache can't grow so we can just get the current values 1892 get_jmethod_id_length_value(jmeths, idnum, &length, &id); 1893 } else { 1894 // cache can grow so we have to be more careful 1895 if (Threads::number_of_threads() == 0 || 1896 SafepointSynchronize::is_at_safepoint()) { 1897 // we're single threaded or at a safepoint - no locking needed 1898 get_jmethod_id_length_value(jmeths, idnum, &length, &id); 1899 } else { 1900 MutexLocker ml(JmethodIdCreation_lock); 1901 get_jmethod_id_length_value(jmeths, idnum, &length, &id); 1902 } 1903 } 1904 } 1905 // implied else: 1906 // we need to allocate a cache so default length and id values are good 1907 1908 if (jmeths == NULL || // no cache yet 1909 length <= idnum || // cache is too short 1910 id == NULL) { // cache doesn't contain entry 1911 1912 // This function can be called by the VMThread so we have to do all 1913 // things that might block on a safepoint before grabbing the lock. 1914 // Otherwise, we can deadlock with the VMThread or have a cache 1915 // consistency issue. These vars keep track of what we might have 1916 // to free after the lock is dropped. 1917 jmethodID to_dealloc_id = NULL; 1918 jmethodID* to_dealloc_jmeths = NULL; 1919 1920 // may not allocate new_jmeths or use it if we allocate it 1921 jmethodID* new_jmeths = NULL; 1922 if (length <= idnum) { 1923 // allocate a new cache that might be used 1924 size_t size = MAX2(idnum+1, (size_t)idnum_allocated_count()); 1925 new_jmeths = NEW_C_HEAP_ARRAY(jmethodID, size+1, mtClass); 1926 memset(new_jmeths, 0, (size+1)*sizeof(jmethodID)); 1927 // cache size is stored in element[0], other elements offset by one 1928 new_jmeths[0] = (jmethodID)size; 1929 } 1930 1931 // allocate a new jmethodID that might be used 1932 jmethodID new_id = NULL; 1933 if (method_h->is_old() && !method_h->is_obsolete()) { 1934 // The method passed in is old (but not obsolete), we need to use the current version 1935 Method* current_method = method_with_idnum((int)idnum); 1936 assert(current_method != NULL, "old and but not obsolete, so should exist"); 1937 new_id = Method::make_jmethod_id(class_loader_data(), current_method); 1938 } else { 1939 // It is the current version of the method or an obsolete method, 1940 // use the version passed in 1941 new_id = Method::make_jmethod_id(class_loader_data(), method_h()); 1942 } 1943 1944 if (Threads::number_of_threads() == 0 || 1945 SafepointSynchronize::is_at_safepoint()) { 1946 // we're single threaded or at a safepoint - no locking needed 1947 id = get_jmethod_id_fetch_or_update(idnum, new_id, new_jmeths, 1948 &to_dealloc_id, &to_dealloc_jmeths); 1949 } else { 1950 MutexLocker ml(JmethodIdCreation_lock); 1951 id = get_jmethod_id_fetch_or_update(idnum, new_id, new_jmeths, 1952 &to_dealloc_id, &to_dealloc_jmeths); 1953 } 1954 1955 // The lock has been dropped so we can free resources. 1956 // Free up either the old cache or the new cache if we allocated one. 1957 if (to_dealloc_jmeths != NULL) { 1958 FreeHeap(to_dealloc_jmeths); 1959 } 1960 // free up the new ID since it wasn't needed 1961 if (to_dealloc_id != NULL) { 1962 Method::destroy_jmethod_id(class_loader_data(), to_dealloc_id); 1963 } 1964 } 1965 return id; 1966 } 1967 1968 // Figure out how many jmethodIDs haven't been allocated, and make 1969 // sure space for them is pre-allocated. This makes getting all 1970 // method ids much, much faster with classes with more than 8 1971 // methods, and has a *substantial* effect on performance with jvmti 1972 // code that loads all jmethodIDs for all classes. 1973 void InstanceKlass::ensure_space_for_methodids(int start_offset) { 1974 int new_jmeths = 0; 1975 int length = methods()->length(); 1976 for (int index = start_offset; index < length; index++) { 1977 Method* m = methods()->at(index); 1978 jmethodID id = m->find_jmethod_id_or_null(); 1979 if (id == NULL) { 1980 new_jmeths++; 1981 } 1982 } 1983 if (new_jmeths != 0) { 1984 Method::ensure_jmethod_ids(class_loader_data(), new_jmeths); 1985 } 1986 } 1987 1988 // Common code to fetch the jmethodID from the cache or update the 1989 // cache with the new jmethodID. This function should never do anything 1990 // that causes the caller to go to a safepoint or we can deadlock with 1991 // the VMThread or have cache consistency issues. 1992 // 1993 jmethodID InstanceKlass::get_jmethod_id_fetch_or_update( 1994 size_t idnum, jmethodID new_id, 1995 jmethodID* new_jmeths, jmethodID* to_dealloc_id_p, 1996 jmethodID** to_dealloc_jmeths_p) { 1997 assert(new_id != NULL, "sanity check"); 1998 assert(to_dealloc_id_p != NULL, "sanity check"); 1999 assert(to_dealloc_jmeths_p != NULL, "sanity check"); 2000 assert(Threads::number_of_threads() == 0 || 2001 SafepointSynchronize::is_at_safepoint() || 2002 JmethodIdCreation_lock->owned_by_self(), "sanity check"); 2003 2004 // reacquire the cache - we are locked, single threaded or at a safepoint 2005 jmethodID* jmeths = methods_jmethod_ids_acquire(); 2006 jmethodID id = NULL; 2007 size_t length = 0; 2008 2009 if (jmeths == NULL || // no cache yet 2010 (length = (size_t)jmeths[0]) <= idnum) { // cache is too short 2011 if (jmeths != NULL) { 2012 // copy any existing entries from the old cache 2013 for (size_t index = 0; index < length; index++) { 2014 new_jmeths[index+1] = jmeths[index+1]; 2015 } 2016 *to_dealloc_jmeths_p = jmeths; // save old cache for later delete 2017 } 2018 release_set_methods_jmethod_ids(jmeths = new_jmeths); 2019 } else { 2020 // fetch jmethodID (if any) from the existing cache 2021 id = jmeths[idnum+1]; 2022 *to_dealloc_jmeths_p = new_jmeths; // save new cache for later delete 2023 } 2024 if (id == NULL) { 2025 // No matching jmethodID in the existing cache or we have a new 2026 // cache or we just grew the cache. This cache write is done here 2027 // by the first thread to win the foot race because a jmethodID 2028 // needs to be unique once it is generally available. 2029 id = new_id; 2030 2031 // The jmethodID cache can be read while unlocked so we have to 2032 // make sure the new jmethodID is complete before installing it 2033 // in the cache. 2034 OrderAccess::release_store(&jmeths[idnum+1], id); 2035 } else { 2036 *to_dealloc_id_p = new_id; // save new id for later delete 2037 } 2038 return id; 2039 } 2040 2041 2042 // Common code to get the jmethodID cache length and the jmethodID 2043 // value at index idnum if there is one. 2044 // 2045 void InstanceKlass::get_jmethod_id_length_value(jmethodID* cache, 2046 size_t idnum, size_t *length_p, jmethodID* id_p) { 2047 assert(cache != NULL, "sanity check"); 2048 assert(length_p != NULL, "sanity check"); 2049 assert(id_p != NULL, "sanity check"); 2050 2051 // cache size is stored in element[0], other elements offset by one 2052 *length_p = (size_t)cache[0]; 2053 if (*length_p <= idnum) { // cache is too short 2054 *id_p = NULL; 2055 } else { 2056 *id_p = cache[idnum+1]; // fetch jmethodID (if any) 2057 } 2058 } 2059 2060 2061 // Lookup a jmethodID, NULL if not found. Do no blocking, no allocations, no handles 2062 jmethodID InstanceKlass::jmethod_id_or_null(Method* method) { 2063 size_t idnum = (size_t)method->method_idnum(); 2064 jmethodID* jmeths = methods_jmethod_ids_acquire(); 2065 size_t length; // length assigned as debugging crumb 2066 jmethodID id = NULL; 2067 if (jmeths != NULL && // If there is a cache 2068 (length = (size_t)jmeths[0]) > idnum) { // and if it is long enough, 2069 id = jmeths[idnum+1]; // Look up the id (may be NULL) 2070 } 2071 return id; 2072 } 2073 2074 inline DependencyContext InstanceKlass::dependencies() { 2075 DependencyContext dep_context(&_dep_context); 2076 return dep_context; 2077 } 2078 2079 int InstanceKlass::mark_dependent_nmethods(KlassDepChange& changes) { 2080 return dependencies().mark_dependent_nmethods(changes); 2081 } 2082 2083 void InstanceKlass::add_dependent_nmethod(nmethod* nm) { 2084 dependencies().add_dependent_nmethod(nm); 2085 } 2086 2087 void InstanceKlass::remove_dependent_nmethod(nmethod* nm, bool delete_immediately) { 2088 dependencies().remove_dependent_nmethod(nm, delete_immediately); 2089 } 2090 2091 #ifndef PRODUCT 2092 void InstanceKlass::print_dependent_nmethods(bool verbose) { 2093 dependencies().print_dependent_nmethods(verbose); 2094 } 2095 2096 bool InstanceKlass::is_dependent_nmethod(nmethod* nm) { 2097 return dependencies().is_dependent_nmethod(nm); 2098 } 2099 #endif //PRODUCT 2100 2101 void InstanceKlass::clean_weak_instanceklass_links() { 2102 clean_implementors_list(); 2103 clean_method_data(); 2104 2105 // Since GC iterates InstanceKlasses sequentially, it is safe to remove stale entries here. 2106 DependencyContext dep_context(&_dep_context); 2107 dep_context.expunge_stale_entries(); 2108 } 2109 2110 void InstanceKlass::clean_implementors_list() { 2111 assert(is_loader_alive(), "this klass should be live"); 2112 if (is_interface()) { 2113 if (ClassUnloading) { 2114 Klass* impl = implementor(); 2115 if (impl != NULL) { 2116 if (!impl->is_loader_alive()) { 2117 // remove this guy 2118 Klass** klass = adr_implementor(); 2119 assert(klass != NULL, "null klass"); 2120 if (klass != NULL) { 2121 *klass = NULL; 2122 } 2123 } 2124 } 2125 } 2126 } 2127 } 2128 2129 void InstanceKlass::clean_method_data() { 2130 for (int m = 0; m < methods()->length(); m++) { 2131 MethodData* mdo = methods()->at(m)->method_data(); 2132 if (mdo != NULL) { 2133 mdo->clean_method_data(/*always_clean*/false); 2134 } 2135 } 2136 } 2137 2138 bool InstanceKlass::supers_have_passed_fingerprint_checks() { 2139 if (java_super() != NULL && !java_super()->has_passed_fingerprint_check()) { 2140 ResourceMark rm; 2141 log_trace(class, fingerprint)("%s : super %s not fingerprinted", external_name(), java_super()->external_name()); 2142 return false; 2143 } 2144 2145 Array<Klass*>* local_interfaces = this->local_interfaces(); 2146 if (local_interfaces != NULL) { 2147 int length = local_interfaces->length(); 2148 for (int i = 0; i < length; i++) { 2149 InstanceKlass* intf = InstanceKlass::cast(local_interfaces->at(i)); 2150 if (!intf->has_passed_fingerprint_check()) { 2151 ResourceMark rm; 2152 log_trace(class, fingerprint)("%s : interface %s not fingerprinted", external_name(), intf->external_name()); 2153 return false; 2154 } 2155 } 2156 } 2157 2158 return true; 2159 } 2160 2161 bool InstanceKlass::should_store_fingerprint(bool is_anonymous) { 2162 #if INCLUDE_AOT 2163 // We store the fingerprint into the InstanceKlass only in the following 2 cases: 2164 if (CalculateClassFingerprint) { 2165 // (1) We are running AOT to generate a shared library. 2166 return true; 2167 } 2168 if (DumpSharedSpaces) { 2169 // (2) We are running -Xshare:dump to create a shared archive 2170 return true; 2171 } 2172 if (UseAOT && is_anonymous) { 2173 // (3) We are using AOT code from a shared library and see an anonymous class 2174 return true; 2175 } 2176 #endif 2177 2178 // In all other cases we might set the _misc_has_passed_fingerprint_check bit, 2179 // but do not store the 64-bit fingerprint to save space. 2180 return false; 2181 } 2182 2183 bool InstanceKlass::has_stored_fingerprint() const { 2184 #if INCLUDE_AOT 2185 return should_store_fingerprint() || is_shared(); 2186 #else 2187 return false; 2188 #endif 2189 } 2190 2191 uint64_t InstanceKlass::get_stored_fingerprint() const { 2192 address adr = adr_fingerprint(); 2193 if (adr != NULL) { 2194 return (uint64_t)Bytes::get_native_u8(adr); // adr may not be 64-bit aligned 2195 } 2196 return 0; 2197 } 2198 2199 void InstanceKlass::store_fingerprint(uint64_t fingerprint) { 2200 address adr = adr_fingerprint(); 2201 if (adr != NULL) { 2202 Bytes::put_native_u8(adr, (u8)fingerprint); // adr may not be 64-bit aligned 2203 2204 ResourceMark rm; 2205 log_trace(class, fingerprint)("stored as " PTR64_FORMAT " for class %s", fingerprint, external_name()); 2206 } 2207 } 2208 2209 void InstanceKlass::metaspace_pointers_do(MetaspaceClosure* it) { 2210 Klass::metaspace_pointers_do(it); 2211 2212 if (log_is_enabled(Trace, cds)) { 2213 ResourceMark rm; 2214 log_trace(cds)("Iter(InstanceKlass): %p (%s)", this, external_name()); 2215 } 2216 2217 it->push(&_annotations); 2218 it->push((Klass**)&_array_klasses); 2219 it->push(&_constants); 2220 it->push(&_inner_classes); 2221 it->push(&_array_name); 2222 #if INCLUDE_JVMTI 2223 it->push(&_previous_versions); 2224 #endif 2225 it->push(&_methods); 2226 it->push(&_default_methods); 2227 it->push(&_local_interfaces); 2228 it->push(&_transitive_interfaces); 2229 it->push(&_method_ordering); 2230 it->push(&_default_vtable_indices); 2231 it->push(&_fields); 2232 2233 if (itable_length() > 0) { 2234 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable(); 2235 int method_table_offset_in_words = ioe->offset()/wordSize; 2236 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words()) 2237 / itableOffsetEntry::size(); 2238 2239 for (int i = 0; i < nof_interfaces; i ++, ioe ++) { 2240 if (ioe->interface_klass() != NULL) { 2241 it->push(ioe->interface_klass_addr()); 2242 itableMethodEntry* ime = ioe->first_method_entry(this); 2243 int n = klassItable::method_count_for_interface(ioe->interface_klass()); 2244 for (int index = 0; index < n; index ++) { 2245 it->push(ime[index].method_addr()); 2246 } 2247 } 2248 } 2249 } 2250 2251 it->push(&_nest_members); 2252 } 2253 2254 void InstanceKlass::remove_unshareable_info() { 2255 Klass::remove_unshareable_info(); 2256 2257 if (is_in_error_state()) { 2258 // Classes are attempted to link during dumping and may fail, 2259 // but these classes are still in the dictionary and class list in CLD. 2260 // Check in_error state first because in_error is > linked state, so 2261 // is_linked() is true. 2262 // If there's a linking error, there is nothing else to remove. 2263 return; 2264 } 2265 2266 // Unlink the class 2267 if (is_linked()) { 2268 unlink_class(); 2269 } 2270 init_implementor(); 2271 2272 constants()->remove_unshareable_info(); 2273 2274 for (int i = 0; i < methods()->length(); i++) { 2275 Method* m = methods()->at(i); 2276 m->remove_unshareable_info(); 2277 } 2278 2279 // do array classes also. 2280 if (array_klasses() != NULL) { 2281 array_klasses()->remove_unshareable_info(); 2282 } 2283 2284 // These are not allocated from metaspace, but they should should all be empty 2285 // during dump time, so we don't need to worry about them in InstanceKlass::iterate(). 2286 guarantee(_source_debug_extension == NULL, "must be"); 2287 guarantee(_dep_context == DependencyContext::EMPTY, "must be"); 2288 guarantee(_osr_nmethods_head == NULL, "must be"); 2289 2290 #if INCLUDE_JVMTI 2291 guarantee(_breakpoints == NULL, "must be"); 2292 guarantee(_previous_versions == NULL, "must be"); 2293 #endif 2294 2295 _init_thread = NULL; 2296 _methods_jmethod_ids = NULL; 2297 _jni_ids = NULL; 2298 _oop_map_cache = NULL; 2299 // clear _nest_host to ensure re-load at runtime 2300 _nest_host = NULL; 2301 } 2302 2303 void InstanceKlass::remove_java_mirror() { 2304 Klass::remove_java_mirror(); 2305 2306 // do array classes also. 2307 if (array_klasses() != NULL) { 2308 array_klasses()->remove_java_mirror(); 2309 } 2310 } 2311 2312 void InstanceKlass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain, TRAPS) { 2313 set_package(loader_data, CHECK); 2314 Klass::restore_unshareable_info(loader_data, protection_domain, CHECK); 2315 2316 Array<Method*>* methods = this->methods(); 2317 int num_methods = methods->length(); 2318 for (int index2 = 0; index2 < num_methods; ++index2) { 2319 methodHandle m(THREAD, methods->at(index2)); 2320 m->restore_unshareable_info(CHECK); 2321 } 2322 if (JvmtiExport::has_redefined_a_class()) { 2323 // Reinitialize vtable because RedefineClasses may have changed some 2324 // entries in this vtable for super classes so the CDS vtable might 2325 // point to old or obsolete entries. RedefineClasses doesn't fix up 2326 // vtables in the shared system dictionary, only the main one. 2327 // It also redefines the itable too so fix that too. 2328 vtable().initialize_vtable(false, CHECK); 2329 itable().initialize_itable(false, CHECK); 2330 } 2331 2332 // restore constant pool resolved references 2333 constants()->restore_unshareable_info(CHECK); 2334 2335 if (array_klasses() != NULL) { 2336 // Array classes have null protection domain. 2337 // --> see ArrayKlass::complete_create_array_klass() 2338 array_klasses()->restore_unshareable_info(ClassLoaderData::the_null_class_loader_data(), Handle(), CHECK); 2339 } 2340 } 2341 2342 // returns true IFF is_in_error_state() has been changed as a result of this call. 2343 bool InstanceKlass::check_sharing_error_state() { 2344 assert(DumpSharedSpaces, "should only be called during dumping"); 2345 bool old_state = is_in_error_state(); 2346 2347 if (!is_in_error_state()) { 2348 bool bad = false; 2349 for (InstanceKlass* sup = java_super(); sup; sup = sup->java_super()) { 2350 if (sup->is_in_error_state()) { 2351 bad = true; 2352 break; 2353 } 2354 } 2355 if (!bad) { 2356 Array<Klass*>* interfaces = transitive_interfaces(); 2357 for (int i = 0; i < interfaces->length(); i++) { 2358 Klass* iface = interfaces->at(i); 2359 if (InstanceKlass::cast(iface)->is_in_error_state()) { 2360 bad = true; 2361 break; 2362 } 2363 } 2364 } 2365 2366 if (bad) { 2367 set_in_error_state(); 2368 } 2369 } 2370 2371 return (old_state != is_in_error_state()); 2372 } 2373 2374 #if INCLUDE_JVMTI 2375 static void clear_all_breakpoints(Method* m) { 2376 m->clear_all_breakpoints(); 2377 } 2378 #endif 2379 2380 void InstanceKlass::notify_unload_class(InstanceKlass* ik) { 2381 // notify the debugger 2382 if (JvmtiExport::should_post_class_unload()) { 2383 JvmtiExport::post_class_unload(ik); 2384 } 2385 2386 // notify ClassLoadingService of class unload 2387 ClassLoadingService::notify_class_unloaded(ik); 2388 } 2389 2390 void InstanceKlass::release_C_heap_structures(InstanceKlass* ik) { 2391 // Clean up C heap 2392 ik->release_C_heap_structures(); 2393 ik->constants()->release_C_heap_structures(); 2394 } 2395 2396 void InstanceKlass::release_C_heap_structures() { 2397 // Can't release the constant pool here because the constant pool can be 2398 // deallocated separately from the InstanceKlass for default methods and 2399 // redefine classes. 2400 2401 // Deallocate oop map cache 2402 if (_oop_map_cache != NULL) { 2403 delete _oop_map_cache; 2404 _oop_map_cache = NULL; 2405 } 2406 2407 // Deallocate JNI identifiers for jfieldIDs 2408 JNIid::deallocate(jni_ids()); 2409 set_jni_ids(NULL); 2410 2411 jmethodID* jmeths = methods_jmethod_ids_acquire(); 2412 if (jmeths != (jmethodID*)NULL) { 2413 release_set_methods_jmethod_ids(NULL); 2414 FreeHeap(jmeths); 2415 } 2416 2417 // Release dependencies. 2418 // It is desirable to use DC::remove_all_dependents() here, but, unfortunately, 2419 // it is not safe (see JDK-8143408). The problem is that the klass dependency 2420 // context can contain live dependencies, since there's a race between nmethod & 2421 // klass unloading. If the klass is dead when nmethod unloading happens, relevant 2422 // dependencies aren't removed from the context associated with the class (see 2423 // nmethod::flush_dependencies). It ends up during klass unloading as seemingly 2424 // live dependencies pointing to unloaded nmethods and causes a crash in 2425 // DC::remove_all_dependents() when it touches unloaded nmethod. 2426 dependencies().wipe(); 2427 2428 #if INCLUDE_JVMTI 2429 // Deallocate breakpoint records 2430 if (breakpoints() != 0x0) { 2431 methods_do(clear_all_breakpoints); 2432 assert(breakpoints() == 0x0, "should have cleared breakpoints"); 2433 } 2434 2435 // deallocate the cached class file 2436 if (_cached_class_file != NULL && !MetaspaceShared::is_in_shared_metaspace(_cached_class_file)) { 2437 os::free(_cached_class_file); 2438 _cached_class_file = NULL; 2439 } 2440 #endif 2441 2442 // Decrement symbol reference counts associated with the unloaded class. 2443 if (_name != NULL) _name->decrement_refcount(); 2444 // unreference array name derived from this class name (arrays of an unloaded 2445 // class can't be referenced anymore). 2446 if (_array_name != NULL) _array_name->decrement_refcount(); 2447 if (_source_debug_extension != NULL) FREE_C_HEAP_ARRAY(char, _source_debug_extension); 2448 } 2449 2450 void InstanceKlass::set_source_debug_extension(const char* array, int length) { 2451 if (array == NULL) { 2452 _source_debug_extension = NULL; 2453 } else { 2454 // Adding one to the attribute length in order to store a null terminator 2455 // character could cause an overflow because the attribute length is 2456 // already coded with an u4 in the classfile, but in practice, it's 2457 // unlikely to happen. 2458 assert((length+1) > length, "Overflow checking"); 2459 char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass); 2460 for (int i = 0; i < length; i++) { 2461 sde[i] = array[i]; 2462 } 2463 sde[length] = '\0'; 2464 _source_debug_extension = sde; 2465 } 2466 } 2467 2468 const char* InstanceKlass::signature_name() const { 2469 int hash_len = 0; 2470 char hash_buf[40]; 2471 2472 // If this is an anonymous class, append a hash to make the name unique 2473 if (is_anonymous()) { 2474 intptr_t hash = (java_mirror() != NULL) ? java_mirror()->identity_hash() : 0; 2475 jio_snprintf(hash_buf, sizeof(hash_buf), "/" UINTX_FORMAT, (uintx)hash); 2476 hash_len = (int)strlen(hash_buf); 2477 } 2478 2479 // Get the internal name as a c string 2480 const char* src = (const char*) (name()->as_C_string()); 2481 const int src_length = (int)strlen(src); 2482 2483 char* dest = NEW_RESOURCE_ARRAY(char, src_length + hash_len + 3); 2484 2485 // Add L as type indicator 2486 int dest_index = 0; 2487 dest[dest_index++] = 'L'; 2488 2489 // Add the actual class name 2490 for (int src_index = 0; src_index < src_length; ) { 2491 dest[dest_index++] = src[src_index++]; 2492 } 2493 2494 // If we have a hash, append it 2495 for (int hash_index = 0; hash_index < hash_len; ) { 2496 dest[dest_index++] = hash_buf[hash_index++]; 2497 } 2498 2499 // Add the semicolon and the NULL 2500 dest[dest_index++] = ';'; 2501 dest[dest_index] = '\0'; 2502 return dest; 2503 } 2504 2505 // Used to obtain the package name from a fully qualified class name. 2506 Symbol* InstanceKlass::package_from_name(const Symbol* name, TRAPS) { 2507 if (name == NULL) { 2508 return NULL; 2509 } else { 2510 if (name->utf8_length() <= 0) { 2511 return NULL; 2512 } 2513 ResourceMark rm; 2514 const char* package_name = ClassLoader::package_from_name((const char*) name->as_C_string()); 2515 if (package_name == NULL) { 2516 return NULL; 2517 } 2518 Symbol* pkg_name = SymbolTable::new_symbol(package_name, THREAD); 2519 return pkg_name; 2520 } 2521 } 2522 2523 ModuleEntry* InstanceKlass::module() const { 2524 if (!in_unnamed_package()) { 2525 return _package_entry->module(); 2526 } 2527 const Klass* host = host_klass(); 2528 if (host == NULL) { 2529 return class_loader_data()->unnamed_module(); 2530 } 2531 return host->class_loader_data()->unnamed_module(); 2532 } 2533 2534 void InstanceKlass::set_package(ClassLoaderData* loader_data, TRAPS) { 2535 2536 // ensure java/ packages only loaded by boot or platform builtin loaders 2537 check_prohibited_package(name(), loader_data, CHECK); 2538 2539 TempNewSymbol pkg_name = package_from_name(name(), CHECK); 2540 2541 if (pkg_name != NULL && loader_data != NULL) { 2542 2543 // Find in class loader's package entry table. 2544 _package_entry = loader_data->packages()->lookup_only(pkg_name); 2545 2546 // If the package name is not found in the loader's package 2547 // entry table, it is an indication that the package has not 2548 // been defined. Consider it defined within the unnamed module. 2549 if (_package_entry == NULL) { 2550 ResourceMark rm; 2551 2552 if (!ModuleEntryTable::javabase_defined()) { 2553 // Before java.base is defined during bootstrapping, define all packages in 2554 // the java.base module. If a non-java.base package is erroneously placed 2555 // in the java.base module it will be caught later when java.base 2556 // is defined by ModuleEntryTable::verify_javabase_packages check. 2557 assert(ModuleEntryTable::javabase_moduleEntry() != NULL, JAVA_BASE_NAME " module is NULL"); 2558 _package_entry = loader_data->packages()->lookup(pkg_name, ModuleEntryTable::javabase_moduleEntry()); 2559 } else { 2560 assert(loader_data->unnamed_module() != NULL, "unnamed module is NULL"); 2561 _package_entry = loader_data->packages()->lookup(pkg_name, 2562 loader_data->unnamed_module()); 2563 } 2564 2565 // A package should have been successfully created 2566 assert(_package_entry != NULL, "Package entry for class %s not found, loader %s", 2567 name()->as_C_string(), loader_data->loader_name_and_id()); 2568 } 2569 2570 if (log_is_enabled(Debug, module)) { 2571 ResourceMark rm; 2572 ModuleEntry* m = _package_entry->module(); 2573 log_trace(module)("Setting package: class: %s, package: %s, loader: %s, module: %s", 2574 external_name(), 2575 pkg_name->as_C_string(), 2576 loader_data->loader_name_and_id(), 2577 (m->is_named() ? m->name()->as_C_string() : UNNAMED_MODULE)); 2578 } 2579 } else { 2580 ResourceMark rm; 2581 log_trace(module)("Setting package: class: %s, package: unnamed, loader: %s, module: %s", 2582 external_name(), 2583 (loader_data != NULL) ? loader_data->loader_name_and_id() : "NULL", 2584 UNNAMED_MODULE); 2585 } 2586 } 2587 2588 2589 // different versions of is_same_class_package 2590 2591 bool InstanceKlass::is_same_class_package(const Klass* class2) const { 2592 oop classloader1 = this->class_loader(); 2593 PackageEntry* classpkg1 = this->package(); 2594 if (class2->is_objArray_klass()) { 2595 class2 = ObjArrayKlass::cast(class2)->bottom_klass(); 2596 } 2597 2598 oop classloader2; 2599 PackageEntry* classpkg2; 2600 if (class2->is_instance_klass()) { 2601 classloader2 = class2->class_loader(); 2602 classpkg2 = class2->package(); 2603 } else { 2604 assert(class2->is_typeArray_klass(), "should be type array"); 2605 classloader2 = NULL; 2606 classpkg2 = NULL; 2607 } 2608 2609 // Same package is determined by comparing class loader 2610 // and package entries. Both must be the same. This rule 2611 // applies even to classes that are defined in the unnamed 2612 // package, they still must have the same class loader. 2613 if (oopDesc::equals(classloader1, classloader2) && (classpkg1 == classpkg2)) { 2614 return true; 2615 } 2616 2617 return false; 2618 } 2619 2620 // return true if this class and other_class are in the same package. Classloader 2621 // and classname information is enough to determine a class's package 2622 bool InstanceKlass::is_same_class_package(oop other_class_loader, 2623 const Symbol* other_class_name) const { 2624 if (!oopDesc::equals(class_loader(), other_class_loader)) { 2625 return false; 2626 } 2627 if (name()->fast_compare(other_class_name) == 0) { 2628 return true; 2629 } 2630 2631 { 2632 ResourceMark rm; 2633 2634 bool bad_class_name = false; 2635 const char* other_pkg = 2636 ClassLoader::package_from_name((const char*) other_class_name->as_C_string(), &bad_class_name); 2637 if (bad_class_name) { 2638 return false; 2639 } 2640 // Check that package_from_name() returns NULL, not "", if there is no package. 2641 assert(other_pkg == NULL || strlen(other_pkg) > 0, "package name is empty string"); 2642 2643 const Symbol* const this_package_name = 2644 this->package() != NULL ? this->package()->name() : NULL; 2645 2646 if (this_package_name == NULL || other_pkg == NULL) { 2647 // One of the two doesn't have a package. Only return true if the other 2648 // one also doesn't have a package. 2649 return (const char*)this_package_name == other_pkg; 2650 } 2651 2652 // Check if package is identical 2653 return this_package_name->equals(other_pkg); 2654 } 2655 } 2656 2657 // Returns true iff super_method can be overridden by a method in targetclassname 2658 // See JLS 3rd edition 8.4.6.1 2659 // Assumes name-signature match 2660 // "this" is InstanceKlass of super_method which must exist 2661 // note that the InstanceKlass of the method in the targetclassname has not always been created yet 2662 bool InstanceKlass::is_override(const methodHandle& super_method, Handle targetclassloader, Symbol* targetclassname, TRAPS) { 2663 // Private methods can not be overridden 2664 if (super_method->is_private()) { 2665 return false; 2666 } 2667 // If super method is accessible, then override 2668 if ((super_method->is_protected()) || 2669 (super_method->is_public())) { 2670 return true; 2671 } 2672 // Package-private methods are not inherited outside of package 2673 assert(super_method->is_package_private(), "must be package private"); 2674 return(is_same_class_package(targetclassloader(), targetclassname)); 2675 } 2676 2677 // Only boot and platform class loaders can define classes in "java/" packages. 2678 void InstanceKlass::check_prohibited_package(Symbol* class_name, 2679 ClassLoaderData* loader_data, 2680 TRAPS) { 2681 if (!loader_data->is_boot_class_loader_data() && 2682 !loader_data->is_platform_class_loader_data() && 2683 class_name != NULL) { 2684 ResourceMark rm(THREAD); 2685 char* name = class_name->as_C_string(); 2686 if (strncmp(name, JAVAPKG, JAVAPKG_LEN) == 0 && name[JAVAPKG_LEN] == '/') { 2687 TempNewSymbol pkg_name = InstanceKlass::package_from_name(class_name, CHECK); 2688 assert(pkg_name != NULL, "Error in parsing package name starting with 'java/'"); 2689 name = pkg_name->as_C_string(); 2690 const char* class_loader_name = loader_data->loader_name_and_id(); 2691 StringUtils::replace_no_expand(name, "/", "."); 2692 const char* msg_text1 = "Class loader (instance of): "; 2693 const char* msg_text2 = " tried to load prohibited package name: "; 2694 size_t len = strlen(msg_text1) + strlen(class_loader_name) + strlen(msg_text2) + strlen(name) + 1; 2695 char* message = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, len); 2696 jio_snprintf(message, len, "%s%s%s%s", msg_text1, class_loader_name, msg_text2, name); 2697 THROW_MSG(vmSymbols::java_lang_SecurityException(), message); 2698 } 2699 } 2700 return; 2701 } 2702 2703 // tell if two classes have the same enclosing class (at package level) 2704 bool InstanceKlass::is_same_package_member(const Klass* class2, TRAPS) const { 2705 if (class2 == this) return true; 2706 if (!class2->is_instance_klass()) return false; 2707 2708 // must be in same package before we try anything else 2709 if (!is_same_class_package(class2)) 2710 return false; 2711 2712 // As long as there is an outer_this.getEnclosingClass, 2713 // shift the search outward. 2714 const InstanceKlass* outer_this = this; 2715 for (;;) { 2716 // As we walk along, look for equalities between outer_this and class2. 2717 // Eventually, the walks will terminate as outer_this stops 2718 // at the top-level class around the original class. 2719 bool ignore_inner_is_member; 2720 const Klass* next = outer_this->compute_enclosing_class(&ignore_inner_is_member, 2721 CHECK_false); 2722 if (next == NULL) break; 2723 if (next == class2) return true; 2724 outer_this = InstanceKlass::cast(next); 2725 } 2726 2727 // Now do the same for class2. 2728 const InstanceKlass* outer2 = InstanceKlass::cast(class2); 2729 for (;;) { 2730 bool ignore_inner_is_member; 2731 Klass* next = outer2->compute_enclosing_class(&ignore_inner_is_member, 2732 CHECK_false); 2733 if (next == NULL) break; 2734 // Might as well check the new outer against all available values. 2735 if (next == this) return true; 2736 if (next == outer_this) return true; 2737 outer2 = InstanceKlass::cast(next); 2738 } 2739 2740 // If by this point we have not found an equality between the 2741 // two classes, we know they are in separate package members. 2742 return false; 2743 } 2744 2745 bool InstanceKlass::find_inner_classes_attr(int* ooff, int* noff, TRAPS) const { 2746 constantPoolHandle i_cp(THREAD, constants()); 2747 for (InnerClassesIterator iter(this); !iter.done(); iter.next()) { 2748 int ioff = iter.inner_class_info_index(); 2749 if (ioff != 0) { 2750 // Check to see if the name matches the class we're looking for 2751 // before attempting to find the class. 2752 if (i_cp->klass_name_at_matches(this, ioff)) { 2753 Klass* inner_klass = i_cp->klass_at(ioff, CHECK_false); 2754 if (this == inner_klass) { 2755 *ooff = iter.outer_class_info_index(); 2756 *noff = iter.inner_name_index(); 2757 return true; 2758 } 2759 } 2760 } 2761 } 2762 return false; 2763 } 2764 2765 InstanceKlass* InstanceKlass::compute_enclosing_class(bool* inner_is_member, TRAPS) const { 2766 InstanceKlass* outer_klass = NULL; 2767 *inner_is_member = false; 2768 int ooff = 0, noff = 0; 2769 bool has_inner_classes_attr = find_inner_classes_attr(&ooff, &noff, THREAD); 2770 if (has_inner_classes_attr) { 2771 constantPoolHandle i_cp(THREAD, constants()); 2772 if (ooff != 0) { 2773 Klass* ok = i_cp->klass_at(ooff, CHECK_NULL); 2774 outer_klass = InstanceKlass::cast(ok); 2775 *inner_is_member = true; 2776 } 2777 if (NULL == outer_klass) { 2778 // It may be anonymous; try for that. 2779 int encl_method_class_idx = enclosing_method_class_index(); 2780 if (encl_method_class_idx != 0) { 2781 Klass* ok = i_cp->klass_at(encl_method_class_idx, CHECK_NULL); 2782 outer_klass = InstanceKlass::cast(ok); 2783 *inner_is_member = false; 2784 } 2785 } 2786 } 2787 2788 // If no inner class attribute found for this class. 2789 if (NULL == outer_klass) return NULL; 2790 2791 // Throws an exception if outer klass has not declared k as an inner klass 2792 // We need evidence that each klass knows about the other, or else 2793 // the system could allow a spoof of an inner class to gain access rights. 2794 Reflection::check_for_inner_class(outer_klass, this, *inner_is_member, CHECK_NULL); 2795 return outer_klass; 2796 } 2797 2798 jint InstanceKlass::compute_modifier_flags(TRAPS) const { 2799 jint access = access_flags().as_int(); 2800 2801 // But check if it happens to be member class. 2802 InnerClassesIterator iter(this); 2803 for (; !iter.done(); iter.next()) { 2804 int ioff = iter.inner_class_info_index(); 2805 // Inner class attribute can be zero, skip it. 2806 // Strange but true: JVM spec. allows null inner class refs. 2807 if (ioff == 0) continue; 2808 2809 // only look at classes that are already loaded 2810 // since we are looking for the flags for our self. 2811 Symbol* inner_name = constants()->klass_name_at(ioff); 2812 if (name() == inner_name) { 2813 // This is really a member class. 2814 access = iter.inner_access_flags(); 2815 break; 2816 } 2817 } 2818 // Remember to strip ACC_SUPER bit 2819 return (access & (~JVM_ACC_SUPER)) & JVM_ACC_WRITTEN_FLAGS; 2820 } 2821 2822 jint InstanceKlass::jvmti_class_status() const { 2823 jint result = 0; 2824 2825 if (is_linked()) { 2826 result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED; 2827 } 2828 2829 if (is_initialized()) { 2830 assert(is_linked(), "Class status is not consistent"); 2831 result |= JVMTI_CLASS_STATUS_INITIALIZED; 2832 } 2833 if (is_in_error_state()) { 2834 result |= JVMTI_CLASS_STATUS_ERROR; 2835 } 2836 return result; 2837 } 2838 2839 Method* InstanceKlass::method_at_itable(Klass* holder, int index, TRAPS) { 2840 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable(); 2841 int method_table_offset_in_words = ioe->offset()/wordSize; 2842 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words()) 2843 / itableOffsetEntry::size(); 2844 2845 for (int cnt = 0 ; ; cnt ++, ioe ++) { 2846 // If the interface isn't implemented by the receiver class, 2847 // the VM should throw IncompatibleClassChangeError. 2848 if (cnt >= nof_interfaces) { 2849 ResourceMark rm(THREAD); 2850 stringStream ss; 2851 bool same_module = (module() == holder->module()); 2852 ss.print("Receiver class %s does not implement " 2853 "the interface %s defining the method to be called " 2854 "(%s%s%s)", 2855 external_name(), holder->external_name(), 2856 (same_module) ? joint_in_module_of_loader(holder) : class_in_module_of_loader(), 2857 (same_module) ? "" : "; ", 2858 (same_module) ? "" : holder->class_in_module_of_loader()); 2859 THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), ss.as_string()); 2860 } 2861 2862 Klass* ik = ioe->interface_klass(); 2863 if (ik == holder) break; 2864 } 2865 2866 itableMethodEntry* ime = ioe->first_method_entry(this); 2867 Method* m = ime[index].method(); 2868 if (m == NULL) { 2869 THROW_NULL(vmSymbols::java_lang_AbstractMethodError()); 2870 } 2871 return m; 2872 } 2873 2874 2875 #if INCLUDE_JVMTI 2876 // update default_methods for redefineclasses for methods that are 2877 // not yet in the vtable due to concurrent subclass define and superinterface 2878 // redefinition 2879 // Note: those in the vtable, should have been updated via adjust_method_entries 2880 void InstanceKlass::adjust_default_methods(InstanceKlass* holder, bool* trace_name_printed) { 2881 // search the default_methods for uses of either obsolete or EMCP methods 2882 if (default_methods() != NULL) { 2883 for (int index = 0; index < default_methods()->length(); index ++) { 2884 Method* old_method = default_methods()->at(index); 2885 if (old_method == NULL || old_method->method_holder() != holder || !old_method->is_old()) { 2886 continue; // skip uninteresting entries 2887 } 2888 assert(!old_method->is_deleted(), "default methods may not be deleted"); 2889 2890 Method* new_method = holder->method_with_idnum(old_method->orig_method_idnum()); 2891 2892 assert(new_method != NULL, "method_with_idnum() should not be NULL"); 2893 assert(old_method != new_method, "sanity check"); 2894 2895 default_methods()->at_put(index, new_method); 2896 if (log_is_enabled(Info, redefine, class, update)) { 2897 ResourceMark rm; 2898 if (!(*trace_name_printed)) { 2899 log_info(redefine, class, update) 2900 ("adjust: klassname=%s default methods from name=%s", 2901 external_name(), old_method->method_holder()->external_name()); 2902 *trace_name_printed = true; 2903 } 2904 log_debug(redefine, class, update, vtables) 2905 ("default method update: %s(%s) ", 2906 new_method->name()->as_C_string(), new_method->signature()->as_C_string()); 2907 } 2908 } 2909 } 2910 } 2911 #endif // INCLUDE_JVMTI 2912 2913 // On-stack replacement stuff 2914 void InstanceKlass::add_osr_nmethod(nmethod* n) { 2915 // only one compilation can be active 2916 { 2917 // This is a short non-blocking critical region, so the no safepoint check is ok. 2918 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag); 2919 assert(n->is_osr_method(), "wrong kind of nmethod"); 2920 n->set_osr_link(osr_nmethods_head()); 2921 set_osr_nmethods_head(n); 2922 // Raise the highest osr level if necessary 2923 if (TieredCompilation) { 2924 Method* m = n->method(); 2925 m->set_highest_osr_comp_level(MAX2(m->highest_osr_comp_level(), n->comp_level())); 2926 } 2927 } 2928 2929 // Get rid of the osr methods for the same bci that have lower levels. 2930 if (TieredCompilation) { 2931 for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) { 2932 nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true); 2933 if (inv != NULL && inv->is_in_use()) { 2934 inv->make_not_entrant(); 2935 } 2936 } 2937 } 2938 } 2939 2940 // Remove osr nmethod from the list. Return true if found and removed. 2941 bool InstanceKlass::remove_osr_nmethod(nmethod* n) { 2942 // This is a short non-blocking critical region, so the no safepoint check is ok. 2943 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag); 2944 assert(n->is_osr_method(), "wrong kind of nmethod"); 2945 nmethod* last = NULL; 2946 nmethod* cur = osr_nmethods_head(); 2947 int max_level = CompLevel_none; // Find the max comp level excluding n 2948 Method* m = n->method(); 2949 // Search for match 2950 bool found = false; 2951 while(cur != NULL && cur != n) { 2952 if (TieredCompilation && m == cur->method()) { 2953 // Find max level before n 2954 max_level = MAX2(max_level, cur->comp_level()); 2955 } 2956 last = cur; 2957 cur = cur->osr_link(); 2958 } 2959 nmethod* next = NULL; 2960 if (cur == n) { 2961 found = true; 2962 next = cur->osr_link(); 2963 if (last == NULL) { 2964 // Remove first element 2965 set_osr_nmethods_head(next); 2966 } else { 2967 last->set_osr_link(next); 2968 } 2969 } 2970 n->set_osr_link(NULL); 2971 if (TieredCompilation) { 2972 cur = next; 2973 while (cur != NULL) { 2974 // Find max level after n 2975 if (m == cur->method()) { 2976 max_level = MAX2(max_level, cur->comp_level()); 2977 } 2978 cur = cur->osr_link(); 2979 } 2980 m->set_highest_osr_comp_level(max_level); 2981 } 2982 return found; 2983 } 2984 2985 int InstanceKlass::mark_osr_nmethods(const Method* m) { 2986 // This is a short non-blocking critical region, so the no safepoint check is ok. 2987 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag); 2988 nmethod* osr = osr_nmethods_head(); 2989 int found = 0; 2990 while (osr != NULL) { 2991 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain"); 2992 if (osr->method() == m) { 2993 osr->mark_for_deoptimization(); 2994 found++; 2995 } 2996 osr = osr->osr_link(); 2997 } 2998 return found; 2999 } 3000 3001 nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const { 3002 // This is a short non-blocking critical region, so the no safepoint check is ok. 3003 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag); 3004 nmethod* osr = osr_nmethods_head(); 3005 nmethod* best = NULL; 3006 while (osr != NULL) { 3007 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain"); 3008 // There can be a time when a c1 osr method exists but we are waiting 3009 // for a c2 version. When c2 completes its osr nmethod we will trash 3010 // the c1 version and only be able to find the c2 version. However 3011 // while we overflow in the c1 code at back branches we don't want to 3012 // try and switch to the same code as we are already running 3013 3014 if (osr->method() == m && 3015 (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) { 3016 if (match_level) { 3017 if (osr->comp_level() == comp_level) { 3018 // Found a match - return it. 3019 return osr; 3020 } 3021 } else { 3022 if (best == NULL || (osr->comp_level() > best->comp_level())) { 3023 if (osr->comp_level() == CompLevel_highest_tier) { 3024 // Found the best possible - return it. 3025 return osr; 3026 } 3027 best = osr; 3028 } 3029 } 3030 } 3031 osr = osr->osr_link(); 3032 } 3033 if (best != NULL && best->comp_level() >= comp_level && match_level == false) { 3034 return best; 3035 } 3036 return NULL; 3037 } 3038 3039 // ----------------------------------------------------------------------------------------------------- 3040 // Printing 3041 3042 #ifndef PRODUCT 3043 3044 #define BULLET " - " 3045 3046 static const char* state_names[] = { 3047 "allocated", "loaded", "linked", "being_initialized", "fully_initialized", "initialization_error" 3048 }; 3049 3050 static void print_vtable(intptr_t* start, int len, outputStream* st) { 3051 for (int i = 0; i < len; i++) { 3052 intptr_t e = start[i]; 3053 st->print("%d : " INTPTR_FORMAT, i, e); 3054 if (e != 0 && ((Metadata*)e)->is_metaspace_object()) { 3055 st->print(" "); 3056 ((Metadata*)e)->print_value_on(st); 3057 } 3058 st->cr(); 3059 } 3060 } 3061 3062 static void print_vtable(vtableEntry* start, int len, outputStream* st) { 3063 return print_vtable(reinterpret_cast<intptr_t*>(start), len, st); 3064 } 3065 3066 void InstanceKlass::print_on(outputStream* st) const { 3067 assert(is_klass(), "must be klass"); 3068 Klass::print_on(st); 3069 3070 st->print(BULLET"instance size: %d", size_helper()); st->cr(); 3071 st->print(BULLET"klass size: %d", size()); st->cr(); 3072 st->print(BULLET"access: "); access_flags().print_on(st); st->cr(); 3073 st->print(BULLET"state: "); st->print_cr("%s", state_names[_init_state]); 3074 st->print(BULLET"name: "); name()->print_value_on(st); st->cr(); 3075 st->print(BULLET"super: "); super()->print_value_on_maybe_null(st); st->cr(); 3076 st->print(BULLET"sub: "); 3077 Klass* sub = subklass(); 3078 int n; 3079 for (n = 0; sub != NULL; n++, sub = sub->next_sibling()) { 3080 if (n < MaxSubklassPrintSize) { 3081 sub->print_value_on(st); 3082 st->print(" "); 3083 } 3084 } 3085 if (n >= MaxSubklassPrintSize) st->print("(" INTX_FORMAT " more klasses...)", n - MaxSubklassPrintSize); 3086 st->cr(); 3087 3088 if (is_interface()) { 3089 st->print_cr(BULLET"nof implementors: %d", nof_implementors()); 3090 if (nof_implementors() == 1) { 3091 st->print_cr(BULLET"implementor: "); 3092 st->print(" "); 3093 implementor()->print_value_on(st); 3094 st->cr(); 3095 } 3096 } 3097 3098 st->print(BULLET"arrays: "); array_klasses()->print_value_on_maybe_null(st); st->cr(); 3099 st->print(BULLET"methods: "); methods()->print_value_on(st); st->cr(); 3100 if (Verbose || WizardMode) { 3101 Array<Method*>* method_array = methods(); 3102 for (int i = 0; i < method_array->length(); i++) { 3103 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr(); 3104 } 3105 } 3106 st->print(BULLET"method ordering: "); method_ordering()->print_value_on(st); st->cr(); 3107 st->print(BULLET"default_methods: "); default_methods()->print_value_on(st); st->cr(); 3108 if (Verbose && default_methods() != NULL) { 3109 Array<Method*>* method_array = default_methods(); 3110 for (int i = 0; i < method_array->length(); i++) { 3111 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr(); 3112 } 3113 } 3114 if (default_vtable_indices() != NULL) { 3115 st->print(BULLET"default vtable indices: "); default_vtable_indices()->print_value_on(st); st->cr(); 3116 } 3117 st->print(BULLET"local interfaces: "); local_interfaces()->print_value_on(st); st->cr(); 3118 st->print(BULLET"trans. interfaces: "); transitive_interfaces()->print_value_on(st); st->cr(); 3119 st->print(BULLET"constants: "); constants()->print_value_on(st); st->cr(); 3120 if (class_loader_data() != NULL) { 3121 st->print(BULLET"class loader data: "); 3122 class_loader_data()->print_value_on(st); 3123 st->cr(); 3124 } 3125 st->print(BULLET"host class: "); host_klass()->print_value_on_maybe_null(st); st->cr(); 3126 if (source_file_name() != NULL) { 3127 st->print(BULLET"source file: "); 3128 source_file_name()->print_value_on(st); 3129 st->cr(); 3130 } 3131 if (source_debug_extension() != NULL) { 3132 st->print(BULLET"source debug extension: "); 3133 st->print("%s", source_debug_extension()); 3134 st->cr(); 3135 } 3136 st->print(BULLET"class annotations: "); class_annotations()->print_value_on(st); st->cr(); 3137 st->print(BULLET"class type annotations: "); class_type_annotations()->print_value_on(st); st->cr(); 3138 st->print(BULLET"field annotations: "); fields_annotations()->print_value_on(st); st->cr(); 3139 st->print(BULLET"field type annotations: "); fields_type_annotations()->print_value_on(st); st->cr(); 3140 { 3141 bool have_pv = false; 3142 // previous versions are linked together through the InstanceKlass 3143 for (InstanceKlass* pv_node = previous_versions(); 3144 pv_node != NULL; 3145 pv_node = pv_node->previous_versions()) { 3146 if (!have_pv) 3147 st->print(BULLET"previous version: "); 3148 have_pv = true; 3149 pv_node->constants()->print_value_on(st); 3150 } 3151 if (have_pv) st->cr(); 3152 } 3153 3154 if (generic_signature() != NULL) { 3155 st->print(BULLET"generic signature: "); 3156 generic_signature()->print_value_on(st); 3157 st->cr(); 3158 } 3159 st->print(BULLET"inner classes: "); inner_classes()->print_value_on(st); st->cr(); 3160 st->print(BULLET"nest members: "); nest_members()->print_value_on(st); st->cr(); 3161 st->print(BULLET"java mirror: "); java_mirror()->print_value_on(st); st->cr(); 3162 st->print(BULLET"vtable length %d (start addr: " INTPTR_FORMAT ")", vtable_length(), p2i(start_of_vtable())); st->cr(); 3163 if (vtable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_vtable(), vtable_length(), st); 3164 st->print(BULLET"itable length %d (start addr: " INTPTR_FORMAT ")", itable_length(), p2i(start_of_itable())); st->cr(); 3165 if (itable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_itable(), itable_length(), st); 3166 st->print_cr(BULLET"---- static fields (%d words):", static_field_size()); 3167 FieldPrinter print_static_field(st); 3168 ((InstanceKlass*)this)->do_local_static_fields(&print_static_field); 3169 st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size()); 3170 FieldPrinter print_nonstatic_field(st); 3171 InstanceKlass* ik = const_cast<InstanceKlass*>(this); 3172 ik->do_nonstatic_fields(&print_nonstatic_field); 3173 3174 st->print(BULLET"non-static oop maps: "); 3175 OopMapBlock* map = start_of_nonstatic_oop_maps(); 3176 OopMapBlock* end_map = map + nonstatic_oop_map_count(); 3177 while (map < end_map) { 3178 st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1)); 3179 map++; 3180 } 3181 st->cr(); 3182 } 3183 3184 #endif //PRODUCT 3185 3186 void InstanceKlass::print_value_on(outputStream* st) const { 3187 assert(is_klass(), "must be klass"); 3188 if (Verbose || WizardMode) access_flags().print_on(st); 3189 name()->print_value_on(st); 3190 } 3191 3192 #ifndef PRODUCT 3193 3194 void FieldPrinter::do_field(fieldDescriptor* fd) { 3195 _st->print(BULLET); 3196 if (_obj == NULL) { 3197 fd->print_on(_st); 3198 _st->cr(); 3199 } else { 3200 fd->print_on_for(_st, _obj); 3201 _st->cr(); 3202 } 3203 } 3204 3205 3206 void InstanceKlass::oop_print_on(oop obj, outputStream* st) { 3207 Klass::oop_print_on(obj, st); 3208 3209 if (this == SystemDictionary::String_klass()) { 3210 typeArrayOop value = java_lang_String::value(obj); 3211 juint length = java_lang_String::length(obj); 3212 if (value != NULL && 3213 value->is_typeArray() && 3214 length <= (juint) value->length()) { 3215 st->print(BULLET"string: "); 3216 java_lang_String::print(obj, st); 3217 st->cr(); 3218 if (!WizardMode) return; // that is enough 3219 } 3220 } 3221 3222 st->print_cr(BULLET"---- fields (total size %d words):", oop_size(obj)); 3223 FieldPrinter print_field(st, obj); 3224 do_nonstatic_fields(&print_field); 3225 3226 if (this == SystemDictionary::Class_klass()) { 3227 st->print(BULLET"signature: "); 3228 java_lang_Class::print_signature(obj, st); 3229 st->cr(); 3230 Klass* mirrored_klass = java_lang_Class::as_Klass(obj); 3231 st->print(BULLET"fake entry for mirror: "); 3232 mirrored_klass->print_value_on_maybe_null(st); 3233 st->cr(); 3234 Klass* array_klass = java_lang_Class::array_klass_acquire(obj); 3235 st->print(BULLET"fake entry for array: "); 3236 array_klass->print_value_on_maybe_null(st); 3237 st->cr(); 3238 st->print_cr(BULLET"fake entry for oop_size: %d", java_lang_Class::oop_size(obj)); 3239 st->print_cr(BULLET"fake entry for static_oop_field_count: %d", java_lang_Class::static_oop_field_count(obj)); 3240 Klass* real_klass = java_lang_Class::as_Klass(obj); 3241 if (real_klass != NULL && real_klass->is_instance_klass()) { 3242 InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field); 3243 } 3244 } else if (this == SystemDictionary::MethodType_klass()) { 3245 st->print(BULLET"signature: "); 3246 java_lang_invoke_MethodType::print_signature(obj, st); 3247 st->cr(); 3248 } 3249 } 3250 3251 #endif //PRODUCT 3252 3253 void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) { 3254 st->print("a "); 3255 name()->print_value_on(st); 3256 obj->print_address_on(st); 3257 if (this == SystemDictionary::String_klass() 3258 && java_lang_String::value(obj) != NULL) { 3259 ResourceMark rm; 3260 int len = java_lang_String::length(obj); 3261 int plen = (len < 24 ? len : 12); 3262 char* str = java_lang_String::as_utf8_string(obj, 0, plen); 3263 st->print(" = \"%s\"", str); 3264 if (len > plen) 3265 st->print("...[%d]", len); 3266 } else if (this == SystemDictionary::Class_klass()) { 3267 Klass* k = java_lang_Class::as_Klass(obj); 3268 st->print(" = "); 3269 if (k != NULL) { 3270 k->print_value_on(st); 3271 } else { 3272 const char* tname = type2name(java_lang_Class::primitive_type(obj)); 3273 st->print("%s", tname ? tname : "type?"); 3274 } 3275 } else if (this == SystemDictionary::MethodType_klass()) { 3276 st->print(" = "); 3277 java_lang_invoke_MethodType::print_signature(obj, st); 3278 } else if (java_lang_boxing_object::is_instance(obj)) { 3279 st->print(" = "); 3280 java_lang_boxing_object::print(obj, st); 3281 } else if (this == SystemDictionary::LambdaForm_klass()) { 3282 oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj); 3283 if (vmentry != NULL) { 3284 st->print(" => "); 3285 vmentry->print_value_on(st); 3286 } 3287 } else if (this == SystemDictionary::MemberName_klass()) { 3288 Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj); 3289 if (vmtarget != NULL) { 3290 st->print(" = "); 3291 vmtarget->print_value_on(st); 3292 } else { 3293 java_lang_invoke_MemberName::clazz(obj)->print_value_on(st); 3294 st->print("."); 3295 java_lang_invoke_MemberName::name(obj)->print_value_on(st); 3296 } 3297 } 3298 } 3299 3300 const char* InstanceKlass::internal_name() const { 3301 return external_name(); 3302 } 3303 3304 void InstanceKlass::print_class_load_logging(ClassLoaderData* loader_data, 3305 const char* module_name, 3306 const ClassFileStream* cfs) const { 3307 if (!log_is_enabled(Info, class, load)) { 3308 return; 3309 } 3310 3311 ResourceMark rm; 3312 LogMessage(class, load) msg; 3313 stringStream info_stream; 3314 3315 // Name and class hierarchy info 3316 info_stream.print("%s", external_name()); 3317 3318 // Source 3319 if (cfs != NULL) { 3320 if (cfs->source() != NULL) { 3321 if (module_name != NULL) { 3322 if (ClassLoader::is_modules_image(cfs->source())) { 3323 info_stream.print(" source: jrt:/%s", module_name); 3324 } else { 3325 info_stream.print(" source: %s", cfs->source()); 3326 } 3327 } else { 3328 info_stream.print(" source: %s", cfs->source()); 3329 } 3330 } else if (loader_data == ClassLoaderData::the_null_class_loader_data()) { 3331 Thread* THREAD = Thread::current(); 3332 Klass* caller = 3333 THREAD->is_Java_thread() 3334 ? ((JavaThread*)THREAD)->security_get_caller_class(1) 3335 : NULL; 3336 // caller can be NULL, for example, during a JVMTI VM_Init hook 3337 if (caller != NULL) { 3338 info_stream.print(" source: instance of %s", caller->external_name()); 3339 } else { 3340 // source is unknown 3341 } 3342 } else { 3343 oop class_loader = loader_data->class_loader(); 3344 info_stream.print(" source: %s", class_loader->klass()->external_name()); 3345 } 3346 } else { 3347 info_stream.print(" source: shared objects file"); 3348 } 3349 3350 msg.info("%s", info_stream.as_string()); 3351 3352 if (log_is_enabled(Debug, class, load)) { 3353 stringStream debug_stream; 3354 3355 // Class hierarchy info 3356 debug_stream.print(" klass: " INTPTR_FORMAT " super: " INTPTR_FORMAT, 3357 p2i(this), p2i(superklass())); 3358 3359 // Interfaces 3360 if (local_interfaces() != NULL && local_interfaces()->length() > 0) { 3361 debug_stream.print(" interfaces:"); 3362 int length = local_interfaces()->length(); 3363 for (int i = 0; i < length; i++) { 3364 debug_stream.print(" " INTPTR_FORMAT, 3365 p2i(InstanceKlass::cast(local_interfaces()->at(i)))); 3366 } 3367 } 3368 3369 // Class loader 3370 debug_stream.print(" loader: ["); 3371 loader_data->print_value_on(&debug_stream); 3372 debug_stream.print("]"); 3373 3374 // Classfile checksum 3375 if (cfs) { 3376 debug_stream.print(" bytes: %d checksum: %08x", 3377 cfs->length(), 3378 ClassLoader::crc32(0, (const char*)cfs->buffer(), 3379 cfs->length())); 3380 } 3381 3382 msg.debug("%s", debug_stream.as_string()); 3383 } 3384 } 3385 3386 #if INCLUDE_SERVICES 3387 // Size Statistics 3388 void InstanceKlass::collect_statistics(KlassSizeStats *sz) const { 3389 Klass::collect_statistics(sz); 3390 3391 sz->_inst_size = wordSize * size_helper(); 3392 sz->_vtab_bytes = wordSize * vtable_length(); 3393 sz->_itab_bytes = wordSize * itable_length(); 3394 sz->_nonstatic_oopmap_bytes = wordSize * nonstatic_oop_map_size(); 3395 3396 int n = 0; 3397 n += (sz->_methods_array_bytes = sz->count_array(methods())); 3398 n += (sz->_method_ordering_bytes = sz->count_array(method_ordering())); 3399 n += (sz->_local_interfaces_bytes = sz->count_array(local_interfaces())); 3400 n += (sz->_transitive_interfaces_bytes = sz->count_array(transitive_interfaces())); 3401 n += (sz->_fields_bytes = sz->count_array(fields())); 3402 n += (sz->_inner_classes_bytes = sz->count_array(inner_classes())); 3403 n += (sz->_nest_members_bytes = sz->count_array(nest_members())); 3404 sz->_ro_bytes += n; 3405 3406 const ConstantPool* cp = constants(); 3407 if (cp) { 3408 cp->collect_statistics(sz); 3409 } 3410 3411 const Annotations* anno = annotations(); 3412 if (anno) { 3413 anno->collect_statistics(sz); 3414 } 3415 3416 const Array<Method*>* methods_array = methods(); 3417 if (methods()) { 3418 for (int i = 0; i < methods_array->length(); i++) { 3419 Method* method = methods_array->at(i); 3420 if (method) { 3421 sz->_method_count ++; 3422 method->collect_statistics(sz); 3423 } 3424 } 3425 } 3426 } 3427 #endif // INCLUDE_SERVICES 3428 3429 // Verification 3430 3431 class VerifyFieldClosure: public BasicOopIterateClosure { 3432 protected: 3433 template <class T> void do_oop_work(T* p) { 3434 oop obj = RawAccess<>::oop_load(p); 3435 if (!oopDesc::is_oop_or_null(obj)) { 3436 tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p2i(p), p2i(obj)); 3437 Universe::print_on(tty); 3438 guarantee(false, "boom"); 3439 } 3440 } 3441 public: 3442 virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); } 3443 virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); } 3444 }; 3445 3446 void InstanceKlass::verify_on(outputStream* st) { 3447 #ifndef PRODUCT 3448 // Avoid redundant verifies, this really should be in product. 3449 if (_verify_count == Universe::verify_count()) return; 3450 _verify_count = Universe::verify_count(); 3451 #endif 3452 3453 // Verify Klass 3454 Klass::verify_on(st); 3455 3456 // Verify that klass is present in ClassLoaderData 3457 guarantee(class_loader_data()->contains_klass(this), 3458 "this class isn't found in class loader data"); 3459 3460 // Verify vtables 3461 if (is_linked()) { 3462 // $$$ This used to be done only for m/s collections. Doing it 3463 // always seemed a valid generalization. (DLD -- 6/00) 3464 vtable().verify(st); 3465 } 3466 3467 // Verify first subklass 3468 if (subklass() != NULL) { 3469 guarantee(subklass()->is_klass(), "should be klass"); 3470 } 3471 3472 // Verify siblings 3473 Klass* super = this->super(); 3474 Klass* sib = next_sibling(); 3475 if (sib != NULL) { 3476 if (sib == this) { 3477 fatal("subclass points to itself " PTR_FORMAT, p2i(sib)); 3478 } 3479 3480 guarantee(sib->is_klass(), "should be klass"); 3481 guarantee(sib->super() == super, "siblings should have same superklass"); 3482 } 3483 3484 // Verify implementor fields 3485 Klass* im = implementor(); 3486 if (im != NULL) { 3487 guarantee(is_interface(), "only interfaces should have implementor set"); 3488 guarantee(im->is_klass(), "should be klass"); 3489 guarantee(!im->is_interface() || im == this, 3490 "implementors cannot be interfaces"); 3491 } 3492 3493 // Verify local interfaces 3494 if (local_interfaces()) { 3495 Array<Klass*>* local_interfaces = this->local_interfaces(); 3496 for (int j = 0; j < local_interfaces->length(); j++) { 3497 Klass* e = local_interfaces->at(j); 3498 guarantee(e->is_klass() && e->is_interface(), "invalid local interface"); 3499 } 3500 } 3501 3502 // Verify transitive interfaces 3503 if (transitive_interfaces() != NULL) { 3504 Array<Klass*>* transitive_interfaces = this->transitive_interfaces(); 3505 for (int j = 0; j < transitive_interfaces->length(); j++) { 3506 Klass* e = transitive_interfaces->at(j); 3507 guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface"); 3508 } 3509 } 3510 3511 // Verify methods 3512 if (methods() != NULL) { 3513 Array<Method*>* methods = this->methods(); 3514 for (int j = 0; j < methods->length(); j++) { 3515 guarantee(methods->at(j)->is_method(), "non-method in methods array"); 3516 } 3517 for (int j = 0; j < methods->length() - 1; j++) { 3518 Method* m1 = methods->at(j); 3519 Method* m2 = methods->at(j + 1); 3520 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly"); 3521 } 3522 } 3523 3524 // Verify method ordering 3525 if (method_ordering() != NULL) { 3526 Array<int>* method_ordering = this->method_ordering(); 3527 int length = method_ordering->length(); 3528 if (JvmtiExport::can_maintain_original_method_order() || 3529 ((UseSharedSpaces || DumpSharedSpaces) && length != 0)) { 3530 guarantee(length == methods()->length(), "invalid method ordering length"); 3531 jlong sum = 0; 3532 for (int j = 0; j < length; j++) { 3533 int original_index = method_ordering->at(j); 3534 guarantee(original_index >= 0, "invalid method ordering index"); 3535 guarantee(original_index < length, "invalid method ordering index"); 3536 sum += original_index; 3537 } 3538 // Verify sum of indices 0,1,...,length-1 3539 guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum"); 3540 } else { 3541 guarantee(length == 0, "invalid method ordering length"); 3542 } 3543 } 3544 3545 // Verify default methods 3546 if (default_methods() != NULL) { 3547 Array<Method*>* methods = this->default_methods(); 3548 for (int j = 0; j < methods->length(); j++) { 3549 guarantee(methods->at(j)->is_method(), "non-method in methods array"); 3550 } 3551 for (int j = 0; j < methods->length() - 1; j++) { 3552 Method* m1 = methods->at(j); 3553 Method* m2 = methods->at(j + 1); 3554 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly"); 3555 } 3556 } 3557 3558 // Verify JNI static field identifiers 3559 if (jni_ids() != NULL) { 3560 jni_ids()->verify(this); 3561 } 3562 3563 // Verify other fields 3564 if (array_klasses() != NULL) { 3565 guarantee(array_klasses()->is_klass(), "should be klass"); 3566 } 3567 if (constants() != NULL) { 3568 guarantee(constants()->is_constantPool(), "should be constant pool"); 3569 } 3570 const Klass* host = host_klass(); 3571 if (host != NULL) { 3572 guarantee(host->is_klass(), "should be klass"); 3573 } 3574 } 3575 3576 void InstanceKlass::oop_verify_on(oop obj, outputStream* st) { 3577 Klass::oop_verify_on(obj, st); 3578 VerifyFieldClosure blk; 3579 obj->oop_iterate(&blk); 3580 } 3581 3582 3583 // JNIid class for jfieldIDs only 3584 // Note to reviewers: 3585 // These JNI functions are just moved over to column 1 and not changed 3586 // in the compressed oops workspace. 3587 JNIid::JNIid(Klass* holder, int offset, JNIid* next) { 3588 _holder = holder; 3589 _offset = offset; 3590 _next = next; 3591 debug_only(_is_static_field_id = false;) 3592 } 3593 3594 3595 JNIid* JNIid::find(int offset) { 3596 JNIid* current = this; 3597 while (current != NULL) { 3598 if (current->offset() == offset) return current; 3599 current = current->next(); 3600 } 3601 return NULL; 3602 } 3603 3604 void JNIid::deallocate(JNIid* current) { 3605 while (current != NULL) { 3606 JNIid* next = current->next(); 3607 delete current; 3608 current = next; 3609 } 3610 } 3611 3612 3613 void JNIid::verify(Klass* holder) { 3614 int first_field_offset = InstanceMirrorKlass::offset_of_static_fields(); 3615 int end_field_offset; 3616 end_field_offset = first_field_offset + (InstanceKlass::cast(holder)->static_field_size() * wordSize); 3617 3618 JNIid* current = this; 3619 while (current != NULL) { 3620 guarantee(current->holder() == holder, "Invalid klass in JNIid"); 3621 #ifdef ASSERT 3622 int o = current->offset(); 3623 if (current->is_static_field_id()) { 3624 guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid"); 3625 } 3626 #endif 3627 current = current->next(); 3628 } 3629 } 3630 3631 #ifdef ASSERT 3632 void InstanceKlass::set_init_state(ClassState state) { 3633 bool good_state = is_shared() ? (_init_state <= state) 3634 : (_init_state < state); 3635 assert(good_state || state == allocated, "illegal state transition"); 3636 _init_state = (u1)state; 3637 } 3638 #endif 3639 3640 #if INCLUDE_JVMTI 3641 3642 // RedefineClasses() support for previous versions 3643 3644 // Globally, there is at least one previous version of a class to walk 3645 // during class unloading, which is saved because old methods in the class 3646 // are still running. Otherwise the previous version list is cleaned up. 3647 bool InstanceKlass::_has_previous_versions = false; 3648 3649 // Returns true if there are previous versions of a class for class 3650 // unloading only. Also resets the flag to false. purge_previous_version 3651 // will set the flag to true if there are any left, i.e., if there's any 3652 // work to do for next time. This is to avoid the expensive code cache 3653 // walk in CLDG::do_unloading(). 3654 bool InstanceKlass::has_previous_versions_and_reset() { 3655 bool ret = _has_previous_versions; 3656 log_trace(redefine, class, iklass, purge)("Class unloading: has_previous_versions = %s", 3657 ret ? "true" : "false"); 3658 _has_previous_versions = false; 3659 return ret; 3660 } 3661 3662 // Purge previous versions before adding new previous versions of the class and 3663 // during class unloading. 3664 void InstanceKlass::purge_previous_version_list() { 3665 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint"); 3666 assert(has_been_redefined(), "Should only be called for main class"); 3667 3668 // Quick exit. 3669 if (previous_versions() == NULL) { 3670 return; 3671 } 3672 3673 // This klass has previous versions so see what we can cleanup 3674 // while it is safe to do so. 3675 3676 int deleted_count = 0; // leave debugging breadcrumbs 3677 int live_count = 0; 3678 ClassLoaderData* loader_data = class_loader_data(); 3679 assert(loader_data != NULL, "should never be null"); 3680 3681 ResourceMark rm; 3682 log_trace(redefine, class, iklass, purge)("%s: previous versions", external_name()); 3683 3684 // previous versions are linked together through the InstanceKlass 3685 InstanceKlass* pv_node = previous_versions(); 3686 InstanceKlass* last = this; 3687 int version = 0; 3688 3689 // check the previous versions list 3690 for (; pv_node != NULL; ) { 3691 3692 ConstantPool* pvcp = pv_node->constants(); 3693 assert(pvcp != NULL, "cp ref was unexpectedly cleared"); 3694 3695 if (!pvcp->on_stack()) { 3696 // If the constant pool isn't on stack, none of the methods 3697 // are executing. Unlink this previous_version. 3698 // The previous version InstanceKlass is on the ClassLoaderData deallocate list 3699 // so will be deallocated during the next phase of class unloading. 3700 log_trace(redefine, class, iklass, purge) 3701 ("previous version " INTPTR_FORMAT " is dead.", p2i(pv_node)); 3702 // For debugging purposes. 3703 pv_node->set_is_scratch_class(); 3704 // Unlink from previous version list. 3705 assert(pv_node->class_loader_data() == loader_data, "wrong loader_data"); 3706 InstanceKlass* next = pv_node->previous_versions(); 3707 pv_node->link_previous_versions(NULL); // point next to NULL 3708 last->link_previous_versions(next); 3709 // Add to the deallocate list after unlinking 3710 loader_data->add_to_deallocate_list(pv_node); 3711 pv_node = next; 3712 deleted_count++; 3713 version++; 3714 continue; 3715 } else { 3716 log_trace(redefine, class, iklass, purge)("previous version " INTPTR_FORMAT " is alive", p2i(pv_node)); 3717 assert(pvcp->pool_holder() != NULL, "Constant pool with no holder"); 3718 guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack"); 3719 live_count++; 3720 // found a previous version for next time we do class unloading 3721 _has_previous_versions = true; 3722 } 3723 3724 // At least one method is live in this previous version. 3725 // Reset dead EMCP methods not to get breakpoints. 3726 // All methods are deallocated when all of the methods for this class are no 3727 // longer running. 3728 Array<Method*>* method_refs = pv_node->methods(); 3729 if (method_refs != NULL) { 3730 log_trace(redefine, class, iklass, purge)("previous methods length=%d", method_refs->length()); 3731 for (int j = 0; j < method_refs->length(); j++) { 3732 Method* method = method_refs->at(j); 3733 3734 if (!method->on_stack()) { 3735 // no breakpoints for non-running methods 3736 if (method->is_running_emcp()) { 3737 method->set_running_emcp(false); 3738 } 3739 } else { 3740 assert (method->is_obsolete() || method->is_running_emcp(), 3741 "emcp method cannot run after emcp bit is cleared"); 3742 log_trace(redefine, class, iklass, purge) 3743 ("purge: %s(%s): prev method @%d in version @%d is alive", 3744 method->name()->as_C_string(), method->signature()->as_C_string(), j, version); 3745 } 3746 } 3747 } 3748 // next previous version 3749 last = pv_node; 3750 pv_node = pv_node->previous_versions(); 3751 version++; 3752 } 3753 log_trace(redefine, class, iklass, purge) 3754 ("previous version stats: live=%d, deleted=%d", live_count, deleted_count); 3755 } 3756 3757 void InstanceKlass::mark_newly_obsolete_methods(Array<Method*>* old_methods, 3758 int emcp_method_count) { 3759 int obsolete_method_count = old_methods->length() - emcp_method_count; 3760 3761 if (emcp_method_count != 0 && obsolete_method_count != 0 && 3762 _previous_versions != NULL) { 3763 // We have a mix of obsolete and EMCP methods so we have to 3764 // clear out any matching EMCP method entries the hard way. 3765 int local_count = 0; 3766 for (int i = 0; i < old_methods->length(); i++) { 3767 Method* old_method = old_methods->at(i); 3768 if (old_method->is_obsolete()) { 3769 // only obsolete methods are interesting 3770 Symbol* m_name = old_method->name(); 3771 Symbol* m_signature = old_method->signature(); 3772 3773 // previous versions are linked together through the InstanceKlass 3774 int j = 0; 3775 for (InstanceKlass* prev_version = _previous_versions; 3776 prev_version != NULL; 3777 prev_version = prev_version->previous_versions(), j++) { 3778 3779 Array<Method*>* method_refs = prev_version->methods(); 3780 for (int k = 0; k < method_refs->length(); k++) { 3781 Method* method = method_refs->at(k); 3782 3783 if (!method->is_obsolete() && 3784 method->name() == m_name && 3785 method->signature() == m_signature) { 3786 // The current RedefineClasses() call has made all EMCP 3787 // versions of this method obsolete so mark it as obsolete 3788 log_trace(redefine, class, iklass, add) 3789 ("%s(%s): flush obsolete method @%d in version @%d", 3790 m_name->as_C_string(), m_signature->as_C_string(), k, j); 3791 3792 method->set_is_obsolete(); 3793 break; 3794 } 3795 } 3796 3797 // The previous loop may not find a matching EMCP method, but 3798 // that doesn't mean that we can optimize and not go any 3799 // further back in the PreviousVersion generations. The EMCP 3800 // method for this generation could have already been made obsolete, 3801 // but there still may be an older EMCP method that has not 3802 // been made obsolete. 3803 } 3804 3805 if (++local_count >= obsolete_method_count) { 3806 // no more obsolete methods so bail out now 3807 break; 3808 } 3809 } 3810 } 3811 } 3812 } 3813 3814 // Save the scratch_class as the previous version if any of the methods are running. 3815 // The previous_versions are used to set breakpoints in EMCP methods and they are 3816 // also used to clean MethodData links to redefined methods that are no longer running. 3817 void InstanceKlass::add_previous_version(InstanceKlass* scratch_class, 3818 int emcp_method_count) { 3819 assert(Thread::current()->is_VM_thread(), 3820 "only VMThread can add previous versions"); 3821 3822 ResourceMark rm; 3823 log_trace(redefine, class, iklass, add) 3824 ("adding previous version ref for %s, EMCP_cnt=%d", scratch_class->external_name(), emcp_method_count); 3825 3826 // Clean out old previous versions for this class 3827 purge_previous_version_list(); 3828 3829 // Mark newly obsolete methods in remaining previous versions. An EMCP method from 3830 // a previous redefinition may be made obsolete by this redefinition. 3831 Array<Method*>* old_methods = scratch_class->methods(); 3832 mark_newly_obsolete_methods(old_methods, emcp_method_count); 3833 3834 // If the constant pool for this previous version of the class 3835 // is not marked as being on the stack, then none of the methods 3836 // in this previous version of the class are on the stack so 3837 // we don't need to add this as a previous version. 3838 ConstantPool* cp_ref = scratch_class->constants(); 3839 if (!cp_ref->on_stack()) { 3840 log_trace(redefine, class, iklass, add)("scratch class not added; no methods are running"); 3841 // For debugging purposes. 3842 scratch_class->set_is_scratch_class(); 3843 scratch_class->class_loader_data()->add_to_deallocate_list(scratch_class); 3844 return; 3845 } 3846 3847 if (emcp_method_count != 0) { 3848 // At least one method is still running, check for EMCP methods 3849 for (int i = 0; i < old_methods->length(); i++) { 3850 Method* old_method = old_methods->at(i); 3851 if (!old_method->is_obsolete() && old_method->on_stack()) { 3852 // if EMCP method (not obsolete) is on the stack, mark as EMCP so that 3853 // we can add breakpoints for it. 3854 3855 // We set the method->on_stack bit during safepoints for class redefinition 3856 // and use this bit to set the is_running_emcp bit. 3857 // After the safepoint, the on_stack bit is cleared and the running emcp 3858 // method may exit. If so, we would set a breakpoint in a method that 3859 // is never reached, but this won't be noticeable to the programmer. 3860 old_method->set_running_emcp(true); 3861 log_trace(redefine, class, iklass, add) 3862 ("EMCP method %s is on_stack " INTPTR_FORMAT, old_method->name_and_sig_as_C_string(), p2i(old_method)); 3863 } else if (!old_method->is_obsolete()) { 3864 log_trace(redefine, class, iklass, add) 3865 ("EMCP method %s is NOT on_stack " INTPTR_FORMAT, old_method->name_and_sig_as_C_string(), p2i(old_method)); 3866 } 3867 } 3868 } 3869 3870 // Add previous version if any methods are still running. 3871 // Set has_previous_version flag for processing during class unloading. 3872 _has_previous_versions = true; 3873 log_trace(redefine, class, iklass, add) ("scratch class added; one of its methods is on_stack."); 3874 assert(scratch_class->previous_versions() == NULL, "shouldn't have a previous version"); 3875 scratch_class->link_previous_versions(previous_versions()); 3876 link_previous_versions(scratch_class); 3877 } // end add_previous_version() 3878 3879 #endif // INCLUDE_JVMTI 3880 3881 Method* InstanceKlass::method_with_idnum(int idnum) { 3882 Method* m = NULL; 3883 if (idnum < methods()->length()) { 3884 m = methods()->at(idnum); 3885 } 3886 if (m == NULL || m->method_idnum() != idnum) { 3887 for (int index = 0; index < methods()->length(); ++index) { 3888 m = methods()->at(index); 3889 if (m->method_idnum() == idnum) { 3890 return m; 3891 } 3892 } 3893 // None found, return null for the caller to handle. 3894 return NULL; 3895 } 3896 return m; 3897 } 3898 3899 3900 Method* InstanceKlass::method_with_orig_idnum(int idnum) { 3901 if (idnum >= methods()->length()) { 3902 return NULL; 3903 } 3904 Method* m = methods()->at(idnum); 3905 if (m != NULL && m->orig_method_idnum() == idnum) { 3906 return m; 3907 } 3908 // Obsolete method idnum does not match the original idnum 3909 for (int index = 0; index < methods()->length(); ++index) { 3910 m = methods()->at(index); 3911 if (m->orig_method_idnum() == idnum) { 3912 return m; 3913 } 3914 } 3915 // None found, return null for the caller to handle. 3916 return NULL; 3917 } 3918 3919 3920 Method* InstanceKlass::method_with_orig_idnum(int idnum, int version) { 3921 InstanceKlass* holder = get_klass_version(version); 3922 if (holder == NULL) { 3923 return NULL; // The version of klass is gone, no method is found 3924 } 3925 Method* method = holder->method_with_orig_idnum(idnum); 3926 return method; 3927 } 3928 3929 #if INCLUDE_JVMTI 3930 JvmtiCachedClassFileData* InstanceKlass::get_cached_class_file() { 3931 if (MetaspaceShared::is_in_shared_metaspace(_cached_class_file)) { 3932 // Ignore the archived class stream data 3933 return NULL; 3934 } else { 3935 return _cached_class_file; 3936 } 3937 } 3938 3939 jint InstanceKlass::get_cached_class_file_len() { 3940 return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file); 3941 } 3942 3943 unsigned char * InstanceKlass::get_cached_class_file_bytes() { 3944 return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file); 3945 } 3946 3947 #if INCLUDE_CDS 3948 JvmtiCachedClassFileData* InstanceKlass::get_archived_class_data() { 3949 if (DumpSharedSpaces) { 3950 return _cached_class_file; 3951 } else { 3952 assert(this->is_shared(), "class should be shared"); 3953 if (MetaspaceShared::is_in_shared_metaspace(_cached_class_file)) { 3954 return _cached_class_file; 3955 } else { 3956 return NULL; 3957 } 3958 } 3959 } 3960 #endif 3961 #endif