1 /* 2 * Copyright (c) 1997, 2017, 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 "aot/aotLoader.hpp" 27 #include "classfile/classFileParser.hpp" 28 #include "classfile/classFileStream.hpp" 29 #include "classfile/classLoader.hpp" 30 #include "classfile/javaClasses.hpp" 31 #include "classfile/moduleEntry.hpp" 32 #include "classfile/systemDictionary.hpp" 33 #include "classfile/systemDictionaryShared.hpp" 34 #include "classfile/verifier.hpp" 35 #include "classfile/vmSymbols.hpp" 36 #include "code/dependencyContext.hpp" 37 #include "compiler/compileBroker.hpp" 38 #include "gc/shared/collectedHeap.inline.hpp" 39 #include "gc/shared/specialized_oop_closures.hpp" 40 #include "interpreter/oopMapCache.hpp" 41 #include "interpreter/rewriter.hpp" 42 #include "jvmtifiles/jvmti.h" 43 #include "logging/log.hpp" 44 #include "logging/logMessage.hpp" 45 #include "memory/heapInspection.hpp" 46 #include "memory/iterator.inline.hpp" 47 #include "memory/metadataFactory.hpp" 48 #include "memory/metaspaceShared.hpp" 49 #include "memory/oopFactory.hpp" 50 #include "memory/resourceArea.hpp" 51 #include "oops/fieldStreams.hpp" 52 #include "oops/instanceClassLoaderKlass.hpp" 53 #include "oops/instanceKlass.inline.hpp" 54 #include "oops/instanceMirrorKlass.hpp" 55 #include "oops/instanceOop.hpp" 56 #include "oops/klass.inline.hpp" 57 #include "oops/method.hpp" 58 #include "oops/oop.inline.hpp" 59 #include "oops/symbol.hpp" 60 #include "oops/valueKlass.hpp" 61 #include "prims/jvmtiExport.hpp" 62 #include "prims/jvmtiRedefineClasses.hpp" 63 #include "prims/jvmtiThreadState.hpp" 64 #include "prims/methodComparator.hpp" 65 #include "runtime/atomic.hpp" 66 #include "runtime/fieldDescriptor.hpp" 67 #include "runtime/handles.inline.hpp" 68 #include "runtime/javaCalls.hpp" 69 #include "runtime/mutexLocker.hpp" 70 #include "runtime/orderAccess.inline.hpp" 71 #include "runtime/thread.inline.hpp" 72 #include "services/classLoadingService.hpp" 73 #include "services/threadService.hpp" 74 #include "utilities/dtrace.hpp" 75 #include "utilities/macros.hpp" 76 #include "utilities/stringUtils.hpp" 77 #ifdef COMPILER1 78 #include "c1/c1_Compiler.hpp" 79 #endif 80 81 #ifdef DTRACE_ENABLED 82 83 84 #define HOTSPOT_CLASS_INITIALIZATION_required HOTSPOT_CLASS_INITIALIZATION_REQUIRED 85 #define HOTSPOT_CLASS_INITIALIZATION_recursive HOTSPOT_CLASS_INITIALIZATION_RECURSIVE 86 #define HOTSPOT_CLASS_INITIALIZATION_concurrent HOTSPOT_CLASS_INITIALIZATION_CONCURRENT 87 #define HOTSPOT_CLASS_INITIALIZATION_erroneous HOTSPOT_CLASS_INITIALIZATION_ERRONEOUS 88 #define HOTSPOT_CLASS_INITIALIZATION_super__failed HOTSPOT_CLASS_INITIALIZATION_SUPER_FAILED 89 #define HOTSPOT_CLASS_INITIALIZATION_clinit HOTSPOT_CLASS_INITIALIZATION_CLINIT 90 #define HOTSPOT_CLASS_INITIALIZATION_error HOTSPOT_CLASS_INITIALIZATION_ERROR 91 #define HOTSPOT_CLASS_INITIALIZATION_end HOTSPOT_CLASS_INITIALIZATION_END 92 #define DTRACE_CLASSINIT_PROBE(type, thread_type) \ 93 { \ 94 char* data = NULL; \ 95 int len = 0; \ 96 Symbol* clss_name = name(); \ 97 if (clss_name != NULL) { \ 98 data = (char*)clss_name->bytes(); \ 99 len = clss_name->utf8_length(); \ 100 } \ 101 HOTSPOT_CLASS_INITIALIZATION_##type( \ 102 data, len, class_loader(), thread_type); \ 103 } 104 105 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait) \ 106 { \ 107 char* data = NULL; \ 108 int len = 0; \ 109 Symbol* clss_name = name(); \ 110 if (clss_name != NULL) { \ 111 data = (char*)clss_name->bytes(); \ 112 len = clss_name->utf8_length(); \ 113 } \ 114 HOTSPOT_CLASS_INITIALIZATION_##type( \ 115 data, len, class_loader(), thread_type, wait); \ 116 } 117 118 #else // ndef DTRACE_ENABLED 119 120 #define DTRACE_CLASSINIT_PROBE(type, thread_type) 121 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait) 122 123 #endif // ndef DTRACE_ENABLED 124 125 volatile int InstanceKlass::_total_instanceKlass_count = 0; 126 127 static inline bool is_class_loader(const Symbol* class_name, 128 const ClassFileParser& parser) { 129 assert(class_name != NULL, "invariant"); 130 131 if (class_name == vmSymbols::java_lang_ClassLoader()) { 132 return true; 133 } 134 135 if (SystemDictionary::ClassLoader_klass_loaded()) { 136 const Klass* const super_klass = parser.super_klass(); 137 if (super_klass != NULL) { 138 if (super_klass->is_subtype_of(SystemDictionary::ClassLoader_klass())) { 139 return true; 140 } 141 } 142 } 143 return false; 144 } 145 146 InstanceKlass* InstanceKlass::allocate_instance_klass(const ClassFileParser& parser, TRAPS) { 147 const int size = InstanceKlass::size(parser.vtable_size(), 148 parser.itable_size(), 149 nonstatic_oop_map_size(parser.total_oop_map_count()), 150 parser.is_interface(), 151 parser.is_anonymous(), 152 should_store_fingerprint(), 153 parser.has_value_fields() ? parser.java_fields_count() : 0, 154 parser.is_value_type()); 155 156 const Symbol* const class_name = parser.class_name(); 157 assert(class_name != NULL, "invariant"); 158 ClassLoaderData* loader_data = parser.loader_data(); 159 assert(loader_data != NULL, "invariant"); 160 161 InstanceKlass* ik; 162 163 // Allocation 164 if (REF_NONE == parser.reference_type()) { 165 if (class_name == vmSymbols::java_lang_Class()) { 166 // mirror 167 ik = new (loader_data, size, THREAD) InstanceMirrorKlass(parser); 168 } 169 else if (is_class_loader(class_name, parser)) { 170 // class loader 171 ik = new (loader_data, size, THREAD) InstanceClassLoaderKlass(parser); 172 } else if (parser.is_value_type()) { 173 // value type 174 ik = new (loader_data, size, THREAD) ValueKlass(parser); 175 } else { 176 // normal 177 ik = new (loader_data, size, THREAD) InstanceKlass(parser, InstanceKlass::_misc_kind_other); 178 } 179 } 180 else { 181 // reference 182 ik = new (loader_data, size, THREAD) InstanceRefKlass(parser); 183 } 184 185 // Check for pending exception before adding to the loader data and incrementing 186 // class count. Can get OOM here. 187 if (HAS_PENDING_EXCEPTION) { 188 return NULL; 189 } 190 191 assert(ik != NULL, "invariant"); 192 193 const bool publicize = !parser.is_internal(); 194 #ifdef ASSERT 195 assert(ik->size() == size, ""); 196 ik->bounds_check((address) ik->start_of_vtable(), false, size); 197 ik->bounds_check((address) ik->start_of_itable(), false, size); 198 ik->bounds_check((address) ik->end_of_itable(), true, size); 199 ik->bounds_check((address) ik->end_of_nonstatic_oop_maps(), true, size); 200 #endif //ASSERT 201 202 // Add all classes to our internal class loader list here, 203 // including classes in the bootstrap (NULL) class loader. 204 loader_data->add_class(ik, publicize); 205 Atomic::inc(&_total_instanceKlass_count); 206 207 return ik; 208 } 209 210 #ifndef PRODUCT 211 bool InstanceKlass::bounds_check(address addr, bool edge_ok, intptr_t size_in_bytes) const { 212 const char* bad = NULL; 213 address end = NULL; 214 if (addr < (address)this) { 215 bad = "before"; 216 } else if (addr == (address)this) { 217 if (edge_ok) return true; 218 bad = "just before"; 219 } else if (addr == (end = (address)this + sizeof(intptr_t) * (size_in_bytes < 0 ? size() : size_in_bytes))) { 220 if (edge_ok) return true; 221 bad = "just after"; 222 } else if (addr > end) { 223 bad = "after"; 224 } else { 225 return true; 226 } 227 tty->print_cr("%s object bounds: " INTPTR_FORMAT " [" INTPTR_FORMAT ".." INTPTR_FORMAT "]", 228 bad, (intptr_t)addr, (intptr_t)this, (intptr_t)end); 229 Verbose = WizardMode = true; this->print(); //@@ 230 return false; 231 } 232 #endif //PRODUCT 233 234 // copy method ordering from resource area to Metaspace 235 void InstanceKlass::copy_method_ordering(const intArray* m, TRAPS) { 236 if (m != NULL) { 237 // allocate a new array and copy contents (memcpy?) 238 _method_ordering = MetadataFactory::new_array<int>(class_loader_data(), m->length(), CHECK); 239 for (int i = 0; i < m->length(); i++) { 240 _method_ordering->at_put(i, m->at(i)); 241 } 242 } else { 243 _method_ordering = Universe::the_empty_int_array(); 244 } 245 } 246 247 // create a new array of vtable_indices for default methods 248 Array<int>* InstanceKlass::create_new_default_vtable_indices(int len, TRAPS) { 249 Array<int>* vtable_indices = MetadataFactory::new_array<int>(class_loader_data(), len, CHECK_NULL); 250 assert(default_vtable_indices() == NULL, "only create once"); 251 set_default_vtable_indices(vtable_indices); 252 return vtable_indices; 253 } 254 255 InstanceKlass::InstanceKlass(const ClassFileParser& parser, unsigned kind) : 256 _static_field_size(parser.static_field_size()), 257 _nonstatic_oop_map_size(nonstatic_oop_map_size(parser.total_oop_map_count())), 258 _itable_len(parser.itable_size()), 259 _reference_type(parser.reference_type()), 260 _extra_flags(0) { 261 set_vtable_length(parser.vtable_size()); 262 set_kind(kind); 263 set_access_flags(parser.access_flags()); 264 set_is_anonymous(parser.is_anonymous()); 265 set_layout_helper(Klass::instance_layout_helper(parser.layout_size(), 266 false)); 267 if (parser.has_value_fields()) { 268 set_has_value_fields(); 269 } 270 _java_fields_count = parser.java_fields_count(); 271 272 assert(NULL == _methods, "underlying memory not zeroed?"); 273 assert(is_instance_klass(), "is layout incorrect?"); 274 assert(size_helper() == parser.layout_size(), "incorrect size_helper?"); 275 } 276 277 void InstanceKlass::deallocate_methods(ClassLoaderData* loader_data, 278 Array<Method*>* methods) { 279 if (methods != NULL && methods != Universe::the_empty_method_array() && 280 !methods->is_shared()) { 281 for (int i = 0; i < methods->length(); i++) { 282 Method* method = methods->at(i); 283 if (method == NULL) continue; // maybe null if error processing 284 // Only want to delete methods that are not executing for RedefineClasses. 285 // The previous version will point to them so they're not totally dangling 286 assert (!method->on_stack(), "shouldn't be called with methods on stack"); 287 MetadataFactory::free_metadata(loader_data, method); 288 } 289 MetadataFactory::free_array<Method*>(loader_data, methods); 290 } 291 } 292 293 void InstanceKlass::deallocate_interfaces(ClassLoaderData* loader_data, 294 const Klass* super_klass, 295 Array<Klass*>* local_interfaces, 296 Array<Klass*>* transitive_interfaces) { 297 // Only deallocate transitive interfaces if not empty, same as super class 298 // or same as local interfaces. See code in parseClassFile. 299 Array<Klass*>* ti = transitive_interfaces; 300 if (ti != Universe::the_empty_klass_array() && ti != local_interfaces) { 301 // check that the interfaces don't come from super class 302 Array<Klass*>* sti = (super_klass == NULL) ? NULL : 303 InstanceKlass::cast(super_klass)->transitive_interfaces(); 304 if (ti != sti && ti != NULL && !ti->is_shared()) { 305 MetadataFactory::free_array<Klass*>(loader_data, ti); 306 } 307 } 308 309 // local interfaces can be empty 310 if (local_interfaces != Universe::the_empty_klass_array() && 311 local_interfaces != NULL && !local_interfaces->is_shared()) { 312 MetadataFactory::free_array<Klass*>(loader_data, local_interfaces); 313 } 314 } 315 316 // This function deallocates the metadata and C heap pointers that the 317 // InstanceKlass points to. 318 void InstanceKlass::deallocate_contents(ClassLoaderData* loader_data) { 319 320 // Orphan the mirror first, CMS thinks it's still live. 321 if (java_mirror() != NULL) { 322 java_lang_Class::set_klass(java_mirror(), NULL); 323 } 324 325 // Need to take this class off the class loader data list. 326 loader_data->remove_class(this); 327 328 // The array_klass for this class is created later, after error handling. 329 // For class redefinition, we keep the original class so this scratch class 330 // doesn't have an array class. Either way, assert that there is nothing 331 // to deallocate. 332 assert(array_klasses() == NULL, "array classes shouldn't be created for this class yet"); 333 334 // Release C heap allocated data that this might point to, which includes 335 // reference counting symbol names. 336 release_C_heap_structures(); 337 338 deallocate_methods(loader_data, methods()); 339 set_methods(NULL); 340 341 if (method_ordering() != NULL && 342 method_ordering() != Universe::the_empty_int_array() && 343 !method_ordering()->is_shared()) { 344 MetadataFactory::free_array<int>(loader_data, method_ordering()); 345 } 346 set_method_ordering(NULL); 347 348 // default methods can be empty 349 if (default_methods() != NULL && 350 default_methods() != Universe::the_empty_method_array() && 351 !default_methods()->is_shared()) { 352 MetadataFactory::free_array<Method*>(loader_data, default_methods()); 353 } 354 // Do NOT deallocate the default methods, they are owned by superinterfaces. 355 set_default_methods(NULL); 356 357 // default methods vtable indices can be empty 358 if (default_vtable_indices() != NULL && 359 !default_vtable_indices()->is_shared()) { 360 MetadataFactory::free_array<int>(loader_data, default_vtable_indices()); 361 } 362 set_default_vtable_indices(NULL); 363 364 365 // This array is in Klass, but remove it with the InstanceKlass since 366 // this place would be the only caller and it can share memory with transitive 367 // interfaces. 368 if (secondary_supers() != NULL && 369 secondary_supers() != Universe::the_empty_klass_array() && 370 secondary_supers() != transitive_interfaces() && 371 !secondary_supers()->is_shared()) { 372 MetadataFactory::free_array<Klass*>(loader_data, secondary_supers()); 373 } 374 set_secondary_supers(NULL); 375 376 deallocate_interfaces(loader_data, super(), local_interfaces(), transitive_interfaces()); 377 set_transitive_interfaces(NULL); 378 set_local_interfaces(NULL); 379 380 if (fields() != NULL && !fields()->is_shared()) { 381 MetadataFactory::free_array<jushort>(loader_data, fields()); 382 } 383 set_fields(NULL, 0); 384 385 // If a method from a redefined class is using this constant pool, don't 386 // delete it, yet. The new class's previous version will point to this. 387 if (constants() != NULL) { 388 assert (!constants()->on_stack(), "shouldn't be called if anything is onstack"); 389 if (!constants()->is_shared()) { 390 MetadataFactory::free_metadata(loader_data, constants()); 391 } 392 // Delete any cached resolution errors for the constant pool 393 SystemDictionary::delete_resolution_error(constants()); 394 395 set_constants(NULL); 396 } 397 398 if (inner_classes() != NULL && 399 inner_classes() != Universe::the_empty_short_array() && 400 !inner_classes()->is_shared()) { 401 MetadataFactory::free_array<jushort>(loader_data, inner_classes()); 402 } 403 set_inner_classes(NULL); 404 405 // We should deallocate the Annotations instance if it's not in shared spaces. 406 if (annotations() != NULL && !annotations()->is_shared()) { 407 MetadataFactory::free_metadata(loader_data, annotations()); 408 } 409 set_annotations(NULL); 410 } 411 412 bool InstanceKlass::should_be_initialized() const { 413 return !is_initialized(); 414 } 415 416 klassItable InstanceKlass::itable() const { 417 return klassItable(const_cast<InstanceKlass*>(this)); 418 } 419 420 void InstanceKlass::eager_initialize(Thread *thread) { 421 if (!EagerInitialization) return; 422 423 if (this->is_not_initialized()) { 424 // abort if the the class has a class initializer 425 if (this->class_initializer() != NULL) return; 426 427 // abort if it is java.lang.Object (initialization is handled in genesis) 428 Klass* super_klass = super(); 429 if (super_klass == NULL) return; 430 431 // abort if the super class should be initialized 432 if (!InstanceKlass::cast(super_klass)->is_initialized()) return; 433 434 // call body to expose the this pointer 435 eager_initialize_impl(); 436 } 437 } 438 439 // JVMTI spec thinks there are signers and protection domain in the 440 // instanceKlass. These accessors pretend these fields are there. 441 // The hprof specification also thinks these fields are in InstanceKlass. 442 oop InstanceKlass::protection_domain() const { 443 // return the protection_domain from the mirror 444 return java_lang_Class::protection_domain(java_mirror()); 445 } 446 447 // To remove these from requires an incompatible change and CCC request. 448 objArrayOop InstanceKlass::signers() const { 449 // return the signers from the mirror 450 return java_lang_Class::signers(java_mirror()); 451 } 452 453 oop InstanceKlass::init_lock() const { 454 // return the init lock from the mirror 455 oop lock = java_lang_Class::init_lock(java_mirror()); 456 // Prevent reordering with any access of initialization state 457 OrderAccess::loadload(); 458 assert((oop)lock != NULL || !is_not_initialized(), // initialized or in_error state 459 "only fully initialized state can have a null lock"); 460 return lock; 461 } 462 463 // Set the initialization lock to null so the object can be GC'ed. Any racing 464 // threads to get this lock will see a null lock and will not lock. 465 // That's okay because they all check for initialized state after getting 466 // the lock and return. 467 void InstanceKlass::fence_and_clear_init_lock() { 468 // make sure previous stores are all done, notably the init_state. 469 OrderAccess::storestore(); 470 java_lang_Class::set_init_lock(java_mirror(), NULL); 471 assert(!is_not_initialized(), "class must be initialized now"); 472 } 473 474 void InstanceKlass::eager_initialize_impl() { 475 EXCEPTION_MARK; 476 HandleMark hm(THREAD); 477 Handle h_init_lock(THREAD, init_lock()); 478 ObjectLocker ol(h_init_lock, THREAD, init_lock() != NULL); 479 480 // abort if someone beat us to the initialization 481 if (!is_not_initialized()) return; // note: not equivalent to is_initialized() 482 483 ClassState old_state = init_state(); 484 link_class_impl(true, THREAD); 485 if (HAS_PENDING_EXCEPTION) { 486 CLEAR_PENDING_EXCEPTION; 487 // Abort if linking the class throws an exception. 488 489 // Use a test to avoid redundantly resetting the state if there's 490 // no change. Set_init_state() asserts that state changes make 491 // progress, whereas here we might just be spinning in place. 492 if (old_state != _init_state) 493 set_init_state(old_state); 494 } else { 495 // linking successfull, mark class as initialized 496 set_init_state(fully_initialized); 497 fence_and_clear_init_lock(); 498 // trace 499 if (log_is_enabled(Info, class, init)) { 500 ResourceMark rm(THREAD); 501 log_info(class, init)("[Initialized %s without side effects]", external_name()); 502 } 503 } 504 } 505 506 507 // See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization 508 // process. The step comments refers to the procedure described in that section. 509 // Note: implementation moved to static method to expose the this pointer. 510 void InstanceKlass::initialize(TRAPS) { 511 if (this->should_be_initialized()) { 512 initialize_impl(CHECK); 513 // Note: at this point the class may be initialized 514 // OR it may be in the state of being initialized 515 // in case of recursive initialization! 516 } else { 517 assert(is_initialized(), "sanity check"); 518 } 519 } 520 521 522 bool InstanceKlass::verify_code(bool throw_verifyerror, TRAPS) { 523 // 1) Verify the bytecodes 524 Verifier::Mode mode = 525 throw_verifyerror ? Verifier::ThrowException : Verifier::NoException; 526 return Verifier::verify(this, mode, should_verify_class(), THREAD); 527 } 528 529 530 // Used exclusively by the shared spaces dump mechanism to prevent 531 // classes mapped into the shared regions in new VMs from appearing linked. 532 533 void InstanceKlass::unlink_class() { 534 assert(is_linked(), "must be linked"); 535 _init_state = loaded; 536 } 537 538 void InstanceKlass::link_class(TRAPS) { 539 assert(is_loaded(), "must be loaded"); 540 if (!is_linked()) { 541 link_class_impl(true, CHECK); 542 } 543 } 544 545 // Called to verify that a class can link during initialization, without 546 // throwing a VerifyError. 547 bool InstanceKlass::link_class_or_fail(TRAPS) { 548 assert(is_loaded(), "must be loaded"); 549 if (!is_linked()) { 550 link_class_impl(false, CHECK_false); 551 } 552 return is_linked(); 553 } 554 555 bool InstanceKlass::link_class_impl(bool throw_verifyerror, TRAPS) { 556 if (DumpSharedSpaces && is_in_error_state()) { 557 // This is for CDS dumping phase only -- we use the in_error_state to indicate that 558 // the class has failed verification. Throwing the NoClassDefFoundError here is just 559 // a convenient way to stop repeat attempts to verify the same (bad) class. 560 // 561 // Note that the NoClassDefFoundError is not part of the JLS, and should not be thrown 562 // if we are executing Java code. This is not a problem for CDS dumping phase since 563 // it doesn't execute any Java code. 564 ResourceMark rm(THREAD); 565 Exceptions::fthrow(THREAD_AND_LOCATION, 566 vmSymbols::java_lang_NoClassDefFoundError(), 567 "Class %s, or one of its supertypes, failed class initialization", 568 external_name()); 569 return false; 570 } 571 // return if already verified 572 if (is_linked()) { 573 return true; 574 } 575 576 // Timing 577 // timer handles recursion 578 assert(THREAD->is_Java_thread(), "non-JavaThread in link_class_impl"); 579 JavaThread* jt = (JavaThread*)THREAD; 580 581 // link super class before linking this class 582 Klass* super_klass = super(); 583 if (super_klass != NULL) { 584 if (super_klass->is_interface()) { // check if super class is an interface 585 ResourceMark rm(THREAD); 586 Exceptions::fthrow( 587 THREAD_AND_LOCATION, 588 vmSymbols::java_lang_IncompatibleClassChangeError(), 589 "class %s has interface %s as super class", 590 external_name(), 591 super_klass->external_name() 592 ); 593 return false; 594 } 595 596 InstanceKlass* ik_super = InstanceKlass::cast(super_klass); 597 ik_super->link_class_impl(throw_verifyerror, CHECK_false); 598 } 599 600 // link all interfaces implemented by this class before linking this class 601 Array<Klass*>* interfaces = local_interfaces(); 602 int num_interfaces = interfaces->length(); 603 for (int index = 0; index < num_interfaces; index++) { 604 InstanceKlass* interk = InstanceKlass::cast(interfaces->at(index)); 605 interk->link_class_impl(throw_verifyerror, CHECK_false); 606 } 607 608 // If a value type is referenced by a class (either as a field type or a 609 // method argument or return type) this value type must be loaded during 610 // the linking of this class because size and properties of the value type 611 // must be known in order to be able to perform value type optimizations 612 613 // Note: circular dependencies between value types are not handled yet 614 615 // Note: one case is not handled yet: arrays of value types => FixMe 616 617 // Note: the current implementation is not optimized because the search for 618 // value types is performed on all classes. It would be more efficient to 619 // detect value types during verification and 'tag' the classes for which 620 // value type loading is required. However, this optimization won't be 621 // applicable to classes that are not verified 622 623 // First step: fields 624 for (JavaFieldStream fs(this); !fs.done(); fs.next()) { 625 ResourceMark rm(THREAD); 626 if (fs.field_descriptor().field_type() == T_VALUETYPE) { 627 Symbol* signature = fs.field_descriptor().signature(); 628 // Get current loader and protection domain first. 629 oop loader = class_loader(); 630 oop prot_domain = protection_domain(); 631 Klass* klass = SystemDictionary::resolve_or_fail(signature, 632 Handle(THREAD, loader), Handle(THREAD, prot_domain), true, 633 THREAD); 634 if (klass == NULL) { 635 THROW_(vmSymbols::java_lang_LinkageError(), false); 636 } 637 } 638 } 639 640 // Second step: methods arguments and return types 641 // for (int i = 0; i < this_k->constants()->length(); i++) { 642 // if (this_k->constants()->tag_at(i).is_method()) { 643 // Symbol* signature = this_k->constants()->signature_ref_at(i); 644 // ResourceMark rm(THREAD); 645 // for (SignatureStream ss(signature); !ss.is_done(); ss.next()) { 646 // if (ss.type() == T_VALUETYPE) { 647 // Symbol* sig = ss.as_symbol(THREAD); 648 // // Get current loader and protection domain first. 649 // oop loader = this_k->class_loader(); 650 // oop protection_domain = this_k->protection_domain(); 651 // 652 // bool ok = SystemDictionary::resolve_or_fail(sig, 653 // Handle(THREAD, loader), Handle(THREAD, protection_domain), true, 654 // THREAD); 655 // if (!ok) { 656 // THROW_(vmSymbols::java_lang_LinkageError(), false); 657 // } 658 // } 659 // } 660 // } 661 // } 662 663 // in case the class is linked in the process of linking its superclasses 664 if (is_linked()) { 665 return true; 666 } 667 668 // trace only the link time for this klass that includes 669 // the verification time 670 PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(), 671 ClassLoader::perf_class_link_selftime(), 672 ClassLoader::perf_classes_linked(), 673 jt->get_thread_stat()->perf_recursion_counts_addr(), 674 jt->get_thread_stat()->perf_timers_addr(), 675 PerfClassTraceTime::CLASS_LINK); 676 677 // verification & rewriting 678 { 679 HandleMark hm(THREAD); 680 Handle h_init_lock(THREAD, init_lock()); 681 ObjectLocker ol(h_init_lock, THREAD, init_lock() != NULL); 682 // rewritten will have been set if loader constraint error found 683 // on an earlier link attempt 684 // don't verify or rewrite if already rewritten 685 // 686 687 if (!is_linked()) { 688 // The VCC must be linked before the DVT 689 if (get_vcc_klass() != NULL) { 690 InstanceKlass::cast(get_vcc_klass())->link_class(CHECK_false); 691 } 692 693 if (!is_rewritten()) { 694 { 695 bool verify_ok = verify_code(throw_verifyerror, THREAD); 696 if (!verify_ok) { 697 return false; 698 } 699 } 700 701 // Just in case a side-effect of verify linked this class already 702 // (which can sometimes happen since the verifier loads classes 703 // using custom class loaders, which are free to initialize things) 704 if (is_linked()) { 705 return true; 706 } 707 708 // also sets rewritten 709 rewrite_class(CHECK_false); 710 } else if (is_shared()) { 711 SystemDictionaryShared::check_verification_constraints(this, CHECK_false); 712 } 713 714 // relocate jsrs and link methods after they are all rewritten 715 link_methods(CHECK_false); 716 717 // Initialize the vtable and interface table after 718 // methods have been rewritten since rewrite may 719 // fabricate new Method*s. 720 // also does loader constraint checking 721 // 722 // initialize_vtable and initialize_itable need to be rerun for 723 // a shared class if the class is not loaded by the NULL classloader. 724 ClassLoaderData * loader_data = class_loader_data(); 725 if (!(is_shared() && 726 loader_data->is_the_null_class_loader_data())) { 727 ResourceMark rm(THREAD); 728 vtable().initialize_vtable(true, CHECK_false); 729 itable().initialize_itable(true, CHECK_false); 730 } 731 #ifdef ASSERT 732 else { 733 vtable().verify(tty, true); 734 // In case itable verification is ever added. 735 // itable().verify(tty, true); 736 } 737 #endif 738 739 set_init_state(linked); 740 if (JvmtiExport::should_post_class_prepare()) { 741 Thread *thread = THREAD; 742 assert(thread->is_Java_thread(), "thread->is_Java_thread()"); 743 JvmtiExport::post_class_prepare((JavaThread *) thread, this); 744 } 745 } 746 } 747 return true; 748 } 749 750 751 // Rewrite the byte codes of all of the methods of a class. 752 // The rewriter must be called exactly once. Rewriting must happen after 753 // verification but before the first method of the class is executed. 754 void InstanceKlass::rewrite_class(TRAPS) { 755 assert(is_loaded(), "must be loaded"); 756 if (is_rewritten()) { 757 assert(is_shared(), "rewriting an unshared class?"); 758 return; 759 } 760 Rewriter::rewrite(this, CHECK); 761 set_rewritten(); 762 } 763 764 // Now relocate and link method entry points after class is rewritten. 765 // This is outside is_rewritten flag. In case of an exception, it can be 766 // executed more than once. 767 void InstanceKlass::link_methods(TRAPS) { 768 int len = methods()->length(); 769 for (int i = len-1; i >= 0; i--) { 770 methodHandle m(THREAD, methods()->at(i)); 771 772 // Set up method entry points for compiler and interpreter . 773 m->link_method(m, CHECK); 774 } 775 } 776 777 // Eagerly initialize superinterfaces that declare default methods (concrete instance: any access) 778 void InstanceKlass::initialize_super_interfaces(TRAPS) { 779 assert (has_nonstatic_concrete_methods(), "caller should have checked this"); 780 for (int i = 0; i < local_interfaces()->length(); ++i) { 781 Klass* iface = local_interfaces()->at(i); 782 InstanceKlass* ik = InstanceKlass::cast(iface); 783 784 // Initialization is depth first search ie. we start with top of the inheritance tree 785 // has_nonstatic_concrete_methods drives searching superinterfaces since it 786 // means has_nonstatic_concrete_methods in its superinterface hierarchy 787 if (ik->has_nonstatic_concrete_methods()) { 788 ik->initialize_super_interfaces(CHECK); 789 } 790 791 // Only initialize() interfaces that "declare" concrete methods. 792 if (ik->should_be_initialized() && ik->declares_nonstatic_concrete_methods()) { 793 ik->initialize(CHECK); 794 } 795 } 796 } 797 798 void InstanceKlass::initialize_impl(TRAPS) { 799 HandleMark hm(THREAD); 800 801 // ensure outer VCC is initialized, possible some crafty code referred to VT 1st 802 if (get_vcc_klass() != NULL) { 803 get_vcc_klass()->initialize(CHECK); 804 } 805 806 // Make sure klass is linked (verified) before initialization 807 // A class could already be verified, since it has been reflected upon. 808 link_class(CHECK); 809 810 DTRACE_CLASSINIT_PROBE(required, -1); 811 812 bool wait = false; 813 814 // refer to the JVM book page 47 for description of steps 815 // Step 1 816 { 817 Handle h_init_lock(THREAD, init_lock()); 818 ObjectLocker ol(h_init_lock, THREAD, init_lock() != NULL); 819 820 Thread *self = THREAD; // it's passed the current thread 821 822 // Step 2 823 // If we were to use wait() instead of waitInterruptibly() then 824 // we might end up throwing IE from link/symbol resolution sites 825 // that aren't expected to throw. This would wreak havoc. See 6320309. 826 while(is_being_initialized() && !is_reentrant_initialization(self)) { 827 wait = true; 828 ol.waitUninterruptibly(CHECK); 829 } 830 831 // Step 3 832 if (is_being_initialized() && is_reentrant_initialization(self)) { 833 DTRACE_CLASSINIT_PROBE_WAIT(recursive, -1, wait); 834 return; 835 } 836 837 // Step 4 838 if (is_initialized()) { 839 DTRACE_CLASSINIT_PROBE_WAIT(concurrent, -1, wait); 840 return; 841 } 842 843 // Step 5 844 if (is_in_error_state()) { 845 DTRACE_CLASSINIT_PROBE_WAIT(erroneous, -1, wait); 846 ResourceMark rm(THREAD); 847 const char* desc = "Could not initialize class "; 848 const char* className = external_name(); 849 size_t msglen = strlen(desc) + strlen(className) + 1; 850 char* message = NEW_RESOURCE_ARRAY(char, msglen); 851 if (NULL == message) { 852 // Out of memory: can't create detailed error message 853 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), className); 854 } else { 855 jio_snprintf(message, msglen, "%s%s", desc, className); 856 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), message); 857 } 858 } 859 860 // Step 6 861 set_init_state(being_initialized); 862 set_init_thread(self); 863 } 864 865 // Step 7 866 // Next, if C is a class rather than an interface, initialize it's super class and super 867 // interfaces. 868 if (!is_interface()) { 869 Klass* super_klass = super(); 870 if (super_klass != NULL && super_klass->should_be_initialized()) { 871 super_klass->initialize(THREAD); 872 } 873 // If C implements any interface that declares a non-static, concrete method, 874 // the initialization of C triggers initialization of its super interfaces. 875 // Only need to recurse if has_nonstatic_concrete_methods which includes declaring and 876 // having a superinterface that declares, non-static, concrete methods 877 if (!HAS_PENDING_EXCEPTION && has_nonstatic_concrete_methods()) { 878 initialize_super_interfaces(THREAD); 879 } 880 881 // If any exceptions, complete abruptly, throwing the same exception as above. 882 if (HAS_PENDING_EXCEPTION) { 883 Handle e(THREAD, PENDING_EXCEPTION); 884 CLEAR_PENDING_EXCEPTION; 885 { 886 EXCEPTION_MARK; 887 // Locks object, set state, and notify all waiting threads 888 set_initialization_state_and_notify(initialization_error, THREAD); 889 CLEAR_PENDING_EXCEPTION; 890 } 891 DTRACE_CLASSINIT_PROBE_WAIT(super__failed, -1, wait); 892 THROW_OOP(e()); 893 } 894 } 895 896 897 // Look for aot compiled methods for this klass, including class initializer. 898 AOTLoader::load_for_klass(this, THREAD); 899 900 // Step 8 901 { 902 assert(THREAD->is_Java_thread(), "non-JavaThread in initialize_impl"); 903 JavaThread* jt = (JavaThread*)THREAD; 904 DTRACE_CLASSINIT_PROBE_WAIT(clinit, -1, wait); 905 // Timer includes any side effects of class initialization (resolution, 906 // etc), but not recursive entry into call_class_initializer(). 907 PerfClassTraceTime timer(ClassLoader::perf_class_init_time(), 908 ClassLoader::perf_class_init_selftime(), 909 ClassLoader::perf_classes_inited(), 910 jt->get_thread_stat()->perf_recursion_counts_addr(), 911 jt->get_thread_stat()->perf_timers_addr(), 912 PerfClassTraceTime::CLASS_CLINIT); 913 call_class_initializer(THREAD); 914 } 915 916 // Step 9 917 if (!HAS_PENDING_EXCEPTION) { 918 set_initialization_state_and_notify(fully_initialized, CHECK); 919 { 920 debug_only(vtable().verify(tty, true);) 921 } 922 } 923 else { 924 // Step 10 and 11 925 Handle e(THREAD, PENDING_EXCEPTION); 926 CLEAR_PENDING_EXCEPTION; 927 // JVMTI has already reported the pending exception 928 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError 929 JvmtiExport::clear_detected_exception((JavaThread*)THREAD); 930 { 931 EXCEPTION_MARK; 932 set_initialization_state_and_notify(initialization_error, THREAD); 933 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, class initialization error is thrown below 934 // JVMTI has already reported the pending exception 935 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError 936 JvmtiExport::clear_detected_exception((JavaThread*)THREAD); 937 } 938 DTRACE_CLASSINIT_PROBE_WAIT(error, -1, wait); 939 if (e->is_a(SystemDictionary::Error_klass())) { 940 THROW_OOP(e()); 941 } else { 942 JavaCallArguments args(e); 943 THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(), 944 vmSymbols::throwable_void_signature(), 945 &args); 946 } 947 } 948 DTRACE_CLASSINIT_PROBE_WAIT(end, -1, wait); 949 } 950 951 952 void InstanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) { 953 Handle h_init_lock(THREAD, init_lock()); 954 if (init_lock() != NULL) { 955 ObjectLocker ol(h_init_lock, THREAD); 956 set_init_state(state); 957 fence_and_clear_init_lock(); 958 ol.notify_all(CHECK); 959 } else { 960 assert(init_lock() != NULL, "The initialization state should never be set twice"); 961 set_init_state(state); 962 } 963 } 964 965 // The embedded _implementor field can only record one implementor. 966 // When there are more than one implementors, the _implementor field 967 // is set to the interface Klass* itself. Following are the possible 968 // values for the _implementor field: 969 // NULL - no implementor 970 // implementor Klass* - one implementor 971 // self - more than one implementor 972 // 973 // The _implementor field only exists for interfaces. 974 void InstanceKlass::add_implementor(Klass* k) { 975 assert(Compile_lock->owned_by_self(), ""); 976 assert(is_interface(), "not interface"); 977 // Filter out my subinterfaces. 978 // (Note: Interfaces are never on the subklass list.) 979 if (InstanceKlass::cast(k)->is_interface()) return; 980 981 // Filter out subclasses whose supers already implement me. 982 // (Note: CHA must walk subclasses of direct implementors 983 // in order to locate indirect implementors.) 984 Klass* sk = k->super(); 985 if (sk != NULL && InstanceKlass::cast(sk)->implements_interface(this)) 986 // We only need to check one immediate superclass, since the 987 // implements_interface query looks at transitive_interfaces. 988 // Any supers of the super have the same (or fewer) transitive_interfaces. 989 return; 990 991 Klass* ik = implementor(); 992 if (ik == NULL) { 993 set_implementor(k); 994 } else if (ik != this) { 995 // There is already an implementor. Use itself as an indicator of 996 // more than one implementors. 997 set_implementor(this); 998 } 999 1000 // The implementor also implements the transitive_interfaces 1001 for (int index = 0; index < local_interfaces()->length(); index++) { 1002 InstanceKlass::cast(local_interfaces()->at(index))->add_implementor(k); 1003 } 1004 } 1005 1006 void InstanceKlass::init_implementor() { 1007 if (is_interface()) { 1008 set_implementor(NULL); 1009 } 1010 } 1011 1012 1013 void InstanceKlass::process_interfaces(Thread *thread) { 1014 // link this class into the implementors list of every interface it implements 1015 for (int i = local_interfaces()->length() - 1; i >= 0; i--) { 1016 assert(local_interfaces()->at(i)->is_klass(), "must be a klass"); 1017 InstanceKlass* interf = InstanceKlass::cast(local_interfaces()->at(i)); 1018 assert(interf->is_interface(), "expected interface"); 1019 interf->add_implementor(this); 1020 } 1021 } 1022 1023 bool InstanceKlass::can_be_primary_super_slow() const { 1024 if (is_interface()) 1025 return false; 1026 else 1027 return Klass::can_be_primary_super_slow(); 1028 } 1029 1030 GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots) { 1031 // The secondaries are the implemented interfaces. 1032 Array<Klass*>* interfaces = transitive_interfaces(); 1033 int num_secondaries = num_extra_slots + interfaces->length(); 1034 if (num_secondaries == 0) { 1035 // Must share this for correct bootstrapping! 1036 set_secondary_supers(Universe::the_empty_klass_array()); 1037 return NULL; 1038 } else if (num_extra_slots == 0) { 1039 // The secondary super list is exactly the same as the transitive interfaces. 1040 // Redefine classes has to be careful not to delete this! 1041 set_secondary_supers(interfaces); 1042 return NULL; 1043 } else { 1044 // Copy transitive interfaces to a temporary growable array to be constructed 1045 // into the secondary super list with extra slots. 1046 GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length()); 1047 for (int i = 0; i < interfaces->length(); i++) { 1048 secondaries->push(interfaces->at(i)); 1049 } 1050 return secondaries; 1051 } 1052 } 1053 1054 bool InstanceKlass::compute_is_subtype_of(Klass* k) { 1055 if (k->is_interface()) { 1056 return implements_interface(k); 1057 } else { 1058 return Klass::compute_is_subtype_of(k); 1059 } 1060 } 1061 1062 bool InstanceKlass::implements_interface(Klass* k) const { 1063 if (this == k) return true; 1064 assert(k->is_interface(), "should be an interface class"); 1065 for (int i = 0; i < transitive_interfaces()->length(); i++) { 1066 if (transitive_interfaces()->at(i) == k) { 1067 return true; 1068 } 1069 } 1070 return false; 1071 } 1072 1073 bool InstanceKlass::is_same_or_direct_interface(Klass *k) const { 1074 // Verify direct super interface 1075 if (this == k) return true; 1076 assert(k->is_interface(), "should be an interface class"); 1077 for (int i = 0; i < local_interfaces()->length(); i++) { 1078 if (local_interfaces()->at(i) == k) { 1079 return true; 1080 } 1081 } 1082 return false; 1083 } 1084 1085 objArrayOop InstanceKlass::allocate_objArray(int n, int length, TRAPS) { 1086 if (length < 0) THROW_0(vmSymbols::java_lang_NegativeArraySizeException()); 1087 if (length > arrayOopDesc::max_array_length(T_OBJECT)) { 1088 report_java_out_of_memory("Requested array size exceeds VM limit"); 1089 JvmtiExport::post_array_size_exhausted(); 1090 THROW_OOP_0(Universe::out_of_memory_error_array_size()); 1091 } 1092 int size = objArrayOopDesc::object_size(length); 1093 Klass* ak = array_klass(n, CHECK_NULL); 1094 objArrayOop o = 1095 (objArrayOop)CollectedHeap::array_allocate(ak, size, length, CHECK_NULL); 1096 return o; 1097 } 1098 1099 instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) { 1100 if (TraceFinalizerRegistration) { 1101 tty->print("Registered "); 1102 i->print_value_on(tty); 1103 tty->print_cr(" (" INTPTR_FORMAT ") as finalizable", p2i(i)); 1104 } 1105 instanceHandle h_i(THREAD, i); 1106 // Pass the handle as argument, JavaCalls::call expects oop as jobjects 1107 JavaValue result(T_VOID); 1108 JavaCallArguments args(h_i); 1109 methodHandle mh (THREAD, Universe::finalizer_register_method()); 1110 JavaCalls::call(&result, mh, &args, CHECK_NULL); 1111 return h_i(); 1112 } 1113 1114 instanceOop InstanceKlass::allocate_instance(TRAPS) { 1115 bool has_finalizer_flag = has_finalizer(); // Query before possible GC 1116 int size = size_helper(); // Query before forming handle. 1117 1118 instanceOop i; 1119 1120 i = (instanceOop)CollectedHeap::obj_allocate(this, size, CHECK_NULL); 1121 if (has_finalizer_flag && !RegisterFinalizersAtInit) { 1122 i = register_finalizer(i, CHECK_NULL); 1123 } 1124 return i; 1125 } 1126 1127 void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) { 1128 if (is_interface() || is_abstract()) { 1129 ResourceMark rm(THREAD); 1130 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError() 1131 : vmSymbols::java_lang_InstantiationException(), external_name()); 1132 } 1133 if (this == SystemDictionary::Class_klass()) { 1134 ResourceMark rm(THREAD); 1135 THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError() 1136 : vmSymbols::java_lang_IllegalAccessException(), external_name()); 1137 } 1138 } 1139 1140 Klass* InstanceKlass::array_klass_impl(bool or_null, int n, TRAPS) { 1141 // Need load-acquire for lock-free read 1142 if (array_klasses_acquire() == NULL) { 1143 if (or_null) return NULL; 1144 1145 ResourceMark rm; 1146 JavaThread *jt = (JavaThread *)THREAD; 1147 { 1148 // Atomic creation of array_klasses 1149 MutexLocker mc(Compile_lock, THREAD); // for vtables 1150 MutexLocker ma(MultiArray_lock, THREAD); 1151 1152 // Check if update has already taken place 1153 if (array_klasses() == NULL) { 1154 Klass* k = ObjArrayKlass::allocate_objArray_klass(class_loader_data(), 1, this, CHECK_NULL); 1155 // use 'release' to pair with lock-free load 1156 release_set_array_klasses(k); 1157 } 1158 } 1159 } 1160 // _this will always be set at this point 1161 ObjArrayKlass* oak = (ObjArrayKlass*)array_klasses(); 1162 if (or_null) { 1163 return oak->array_klass_or_null(n); 1164 } 1165 return oak->array_klass(n, THREAD); 1166 } 1167 1168 Klass* InstanceKlass::array_klass_impl(bool or_null, TRAPS) { 1169 return array_klass_impl(or_null, 1, THREAD); 1170 } 1171 1172 static int call_class_initializer_counter = 0; // for debugging 1173 1174 Method* InstanceKlass::class_initializer() const { 1175 Method* clinit = find_method( 1176 vmSymbols::class_initializer_name(), vmSymbols::void_method_signature()); 1177 if (clinit != NULL && clinit->has_valid_initializer_flags()) { 1178 return clinit; 1179 } 1180 return NULL; 1181 } 1182 1183 void InstanceKlass::call_class_initializer(TRAPS) { 1184 if (ReplayCompiles && 1185 (ReplaySuppressInitializers == 1 || 1186 ReplaySuppressInitializers >= 2 && class_loader() != NULL)) { 1187 // Hide the existence of the initializer for the purpose of replaying the compile 1188 return; 1189 } 1190 1191 methodHandle h_method(THREAD, class_initializer()); 1192 assert(!is_initialized(), "we cannot initialize twice"); 1193 if (log_is_enabled(Info, class, init)) { 1194 ResourceMark rm; 1195 outputStream* log = Log(class, init)::info_stream(); 1196 log->print("%d Initializing ", call_class_initializer_counter++); 1197 name()->print_value_on(log); 1198 log->print_cr("%s (" INTPTR_FORMAT ")", h_method() == NULL ? "(no method)" : "", p2i(this)); 1199 } 1200 if (h_method() != NULL) { 1201 JavaCallArguments args; // No arguments 1202 JavaValue result(T_VOID); 1203 JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args) 1204 } 1205 } 1206 1207 1208 void InstanceKlass::mask_for(const methodHandle& method, int bci, 1209 InterpreterOopMap* entry_for) { 1210 // Lazily create the _oop_map_cache at first request 1211 // Lock-free access requires load_ptr_acquire. 1212 OopMapCache* oop_map_cache = 1213 static_cast<OopMapCache*>(OrderAccess::load_ptr_acquire(&_oop_map_cache)); 1214 if (oop_map_cache == NULL) { 1215 MutexLocker x(OopMapCacheAlloc_lock); 1216 // Check if _oop_map_cache was allocated while we were waiting for this lock 1217 if ((oop_map_cache = _oop_map_cache) == NULL) { 1218 oop_map_cache = new OopMapCache(); 1219 // Ensure _oop_map_cache is stable, since it is examined without a lock 1220 OrderAccess::release_store_ptr(&_oop_map_cache, oop_map_cache); 1221 } 1222 } 1223 // _oop_map_cache is constant after init; lookup below does its own locking. 1224 oop_map_cache->lookup(method, bci, entry_for); 1225 } 1226 1227 1228 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const { 1229 for (JavaFieldStream fs(this); !fs.done(); fs.next()) { 1230 Symbol* f_name = fs.name(); 1231 Symbol* f_sig = fs.signature(); 1232 if (f_name == name && f_sig == sig) { 1233 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index()); 1234 return true; 1235 } 1236 } 1237 return false; 1238 } 1239 1240 1241 Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const { 1242 const int n = local_interfaces()->length(); 1243 for (int i = 0; i < n; i++) { 1244 Klass* intf1 = local_interfaces()->at(i); 1245 assert(intf1->is_interface(), "just checking type"); 1246 // search for field in current interface 1247 if (InstanceKlass::cast(intf1)->find_local_field(name, sig, fd)) { 1248 assert(fd->is_static(), "interface field must be static"); 1249 return intf1; 1250 } 1251 // search for field in direct superinterfaces 1252 Klass* intf2 = InstanceKlass::cast(intf1)->find_interface_field(name, sig, fd); 1253 if (intf2 != NULL) return intf2; 1254 } 1255 // otherwise field lookup fails 1256 return NULL; 1257 } 1258 1259 1260 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const { 1261 // search order according to newest JVM spec (5.4.3.2, p.167). 1262 // 1) search for field in current klass 1263 if (find_local_field(name, sig, fd)) { 1264 return const_cast<InstanceKlass*>(this); 1265 } 1266 // 2) search for field recursively in direct superinterfaces 1267 { Klass* intf = find_interface_field(name, sig, fd); 1268 if (intf != NULL) return intf; 1269 } 1270 // 3) apply field lookup recursively if superclass exists 1271 { Klass* supr = super(); 1272 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, fd); 1273 } 1274 // 4) otherwise field lookup fails 1275 return NULL; 1276 } 1277 1278 1279 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const { 1280 // search order according to newest JVM spec (5.4.3.2, p.167). 1281 // 1) search for field in current klass 1282 if (find_local_field(name, sig, fd)) { 1283 if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this); 1284 } 1285 // 2) search for field recursively in direct superinterfaces 1286 if (is_static) { 1287 Klass* intf = find_interface_field(name, sig, fd); 1288 if (intf != NULL) return intf; 1289 } 1290 // 3) apply field lookup recursively if superclass exists 1291 { Klass* supr = super(); 1292 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, is_static, fd); 1293 } 1294 // 4) otherwise field lookup fails 1295 return NULL; 1296 } 1297 1298 1299 bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const { 1300 for (JavaFieldStream fs(this); !fs.done(); fs.next()) { 1301 if (fs.offset() == offset) { 1302 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index()); 1303 if (fd->is_static() == is_static) return true; 1304 } 1305 } 1306 return false; 1307 } 1308 1309 1310 bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const { 1311 Klass* klass = const_cast<InstanceKlass*>(this); 1312 while (klass != NULL) { 1313 if (InstanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) { 1314 return true; 1315 } 1316 klass = klass->super(); 1317 } 1318 return false; 1319 } 1320 1321 1322 void InstanceKlass::methods_do(void f(Method* method)) { 1323 // Methods aren't stable until they are loaded. This can be read outside 1324 // a lock through the ClassLoaderData for profiling 1325 if (!is_loaded()) { 1326 return; 1327 } 1328 1329 int len = methods()->length(); 1330 for (int index = 0; index < len; index++) { 1331 Method* m = methods()->at(index); 1332 assert(m->is_method(), "must be method"); 1333 f(m); 1334 } 1335 } 1336 1337 1338 void InstanceKlass::do_local_static_fields(FieldClosure* cl) { 1339 for (JavaFieldStream fs(this); !fs.done(); fs.next()) { 1340 if (fs.access_flags().is_static()) { 1341 fieldDescriptor& fd = fs.field_descriptor(); 1342 cl->do_field(&fd); 1343 } 1344 } 1345 } 1346 1347 1348 void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle mirror, TRAPS) { 1349 for (JavaFieldStream fs(this); !fs.done(); fs.next()) { 1350 if (fs.access_flags().is_static()) { 1351 fieldDescriptor& fd = fs.field_descriptor(); 1352 f(&fd, mirror, CHECK); 1353 } 1354 } 1355 } 1356 1357 1358 static int compare_fields_by_offset(int* a, int* b) { 1359 return a[0] - b[0]; 1360 } 1361 1362 void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) { 1363 InstanceKlass* super = superklass(); 1364 if (super != NULL) { 1365 super->do_nonstatic_fields(cl); 1366 } 1367 fieldDescriptor fd; 1368 int length = java_fields_count(); 1369 // In DebugInfo nonstatic fields are sorted by offset. 1370 int* fields_sorted = NEW_C_HEAP_ARRAY(int, 2*(length+1), mtClass); 1371 int j = 0; 1372 for (int i = 0; i < length; i += 1) { 1373 fd.reinitialize(this, i); 1374 if (!fd.is_static()) { 1375 fields_sorted[j + 0] = fd.offset(); 1376 fields_sorted[j + 1] = i; 1377 j += 2; 1378 } 1379 } 1380 if (j > 0) { 1381 length = j; 1382 // _sort_Fn is defined in growableArray.hpp. 1383 qsort(fields_sorted, length/2, 2*sizeof(int), (_sort_Fn)compare_fields_by_offset); 1384 for (int i = 0; i < length; i += 2) { 1385 fd.reinitialize(this, fields_sorted[i + 1]); 1386 assert(!fd.is_static() && fd.offset() == fields_sorted[i], "only nonstatic fields"); 1387 cl->do_field(&fd); 1388 } 1389 } 1390 FREE_C_HEAP_ARRAY(int, fields_sorted); 1391 } 1392 1393 1394 void InstanceKlass::array_klasses_do(void f(Klass* k, TRAPS), TRAPS) { 1395 if (array_klasses() != NULL) 1396 ArrayKlass::cast(array_klasses())->array_klasses_do(f, THREAD); 1397 } 1398 1399 void InstanceKlass::array_klasses_do(void f(Klass* k)) { 1400 if (array_klasses() != NULL) 1401 ArrayKlass::cast(array_klasses())->array_klasses_do(f); 1402 } 1403 1404 #ifdef ASSERT 1405 static int linear_search(const Array<Method*>* methods, 1406 const Symbol* name, 1407 const Symbol* signature) { 1408 const int len = methods->length(); 1409 for (int index = 0; index < len; index++) { 1410 const Method* const m = methods->at(index); 1411 assert(m->is_method(), "must be method"); 1412 if (m->signature() == signature && m->name() == name) { 1413 return index; 1414 } 1415 } 1416 return -1; 1417 } 1418 #endif 1419 1420 static int binary_search(const Array<Method*>* methods, const Symbol* name) { 1421 int len = methods->length(); 1422 // methods are sorted, so do binary search 1423 int l = 0; 1424 int h = len - 1; 1425 while (l <= h) { 1426 int mid = (l + h) >> 1; 1427 Method* m = methods->at(mid); 1428 assert(m->is_method(), "must be method"); 1429 int res = m->name()->fast_compare(name); 1430 if (res == 0) { 1431 return mid; 1432 } else if (res < 0) { 1433 l = mid + 1; 1434 } else { 1435 h = mid - 1; 1436 } 1437 } 1438 return -1; 1439 } 1440 1441 // find_method looks up the name/signature in the local methods array 1442 Method* InstanceKlass::find_method(const Symbol* name, 1443 const Symbol* signature) const { 1444 return find_method_impl(name, signature, find_overpass, find_static, find_private); 1445 } 1446 1447 Method* InstanceKlass::find_method_impl(const Symbol* name, 1448 const Symbol* signature, 1449 OverpassLookupMode overpass_mode, 1450 StaticLookupMode static_mode, 1451 PrivateLookupMode private_mode) const { 1452 return InstanceKlass::find_method_impl(methods(), 1453 name, 1454 signature, 1455 overpass_mode, 1456 static_mode, 1457 private_mode); 1458 } 1459 1460 // find_instance_method looks up the name/signature in the local methods array 1461 // and skips over static methods 1462 Method* InstanceKlass::find_instance_method(const Array<Method*>* methods, 1463 const Symbol* name, 1464 const Symbol* signature) { 1465 Method* const meth = InstanceKlass::find_method_impl(methods, 1466 name, 1467 signature, 1468 find_overpass, 1469 skip_static, 1470 find_private); 1471 assert(((meth == NULL) || !meth->is_static()), 1472 "find_instance_method should have skipped statics"); 1473 return meth; 1474 } 1475 1476 // find_instance_method looks up the name/signature in the local methods array 1477 // and skips over static methods 1478 Method* InstanceKlass::find_instance_method(const Symbol* name, const Symbol* signature) const { 1479 return InstanceKlass::find_instance_method(methods(), name, signature); 1480 } 1481 1482 // Find looks up the name/signature in the local methods array 1483 // and filters on the overpass, static and private flags 1484 // This returns the first one found 1485 // note that the local methods array can have up to one overpass, one static 1486 // and one instance (private or not) with the same name/signature 1487 Method* InstanceKlass::find_local_method(const Symbol* name, 1488 const Symbol* signature, 1489 OverpassLookupMode overpass_mode, 1490 StaticLookupMode static_mode, 1491 PrivateLookupMode private_mode) const { 1492 return InstanceKlass::find_method_impl(methods(), 1493 name, 1494 signature, 1495 overpass_mode, 1496 static_mode, 1497 private_mode); 1498 } 1499 1500 // Find looks up the name/signature in the local methods array 1501 // and filters on the overpass, static and private flags 1502 // This returns the first one found 1503 // note that the local methods array can have up to one overpass, one static 1504 // and one instance (private or not) with the same name/signature 1505 Method* InstanceKlass::find_local_method(const Array<Method*>* methods, 1506 const Symbol* name, 1507 const Symbol* signature, 1508 OverpassLookupMode overpass_mode, 1509 StaticLookupMode static_mode, 1510 PrivateLookupMode private_mode) { 1511 return InstanceKlass::find_method_impl(methods, 1512 name, 1513 signature, 1514 overpass_mode, 1515 static_mode, 1516 private_mode); 1517 } 1518 1519 Method* InstanceKlass::find_method(const Array<Method*>* methods, 1520 const Symbol* name, 1521 const Symbol* signature) { 1522 return InstanceKlass::find_method_impl(methods, 1523 name, 1524 signature, 1525 find_overpass, 1526 find_static, 1527 find_private); 1528 } 1529 1530 Method* InstanceKlass::find_method_impl(const Array<Method*>* methods, 1531 const Symbol* name, 1532 const Symbol* signature, 1533 OverpassLookupMode overpass_mode, 1534 StaticLookupMode static_mode, 1535 PrivateLookupMode private_mode) { 1536 int hit = find_method_index(methods, name, signature, overpass_mode, static_mode, private_mode); 1537 return hit >= 0 ? methods->at(hit): NULL; 1538 } 1539 1540 // true if method matches signature and conforms to skipping_X conditions. 1541 static bool method_matches(const Method* m, 1542 const Symbol* signature, 1543 bool skipping_overpass, 1544 bool skipping_static, 1545 bool skipping_private) { 1546 return ((m->signature() == signature) && 1547 (!skipping_overpass || !m->is_overpass()) && 1548 (!skipping_static || !m->is_static()) && 1549 (!skipping_private || !m->is_private())); 1550 } 1551 1552 // Used directly for default_methods to find the index into the 1553 // default_vtable_indices, and indirectly by find_method 1554 // find_method_index looks in the local methods array to return the index 1555 // of the matching name/signature. If, overpass methods are being ignored, 1556 // the search continues to find a potential non-overpass match. This capability 1557 // is important during method resolution to prefer a static method, for example, 1558 // over an overpass method. 1559 // There is the possibility in any _method's array to have the same name/signature 1560 // for a static method, an overpass method and a local instance method 1561 // To correctly catch a given method, the search criteria may need 1562 // to explicitly skip the other two. For local instance methods, it 1563 // is often necessary to skip private methods 1564 int InstanceKlass::find_method_index(const Array<Method*>* methods, 1565 const Symbol* name, 1566 const Symbol* signature, 1567 OverpassLookupMode overpass_mode, 1568 StaticLookupMode static_mode, 1569 PrivateLookupMode private_mode) { 1570 const bool skipping_overpass = (overpass_mode == skip_overpass); 1571 const bool skipping_static = (static_mode == skip_static); 1572 const bool skipping_private = (private_mode == skip_private); 1573 const int hit = binary_search(methods, name); 1574 if (hit != -1) { 1575 const Method* const m = methods->at(hit); 1576 1577 // Do linear search to find matching signature. First, quick check 1578 // for common case, ignoring overpasses if requested. 1579 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) { 1580 return hit; 1581 } 1582 1583 // search downwards through overloaded methods 1584 int i; 1585 for (i = hit - 1; i >= 0; --i) { 1586 const Method* const m = methods->at(i); 1587 assert(m->is_method(), "must be method"); 1588 if (m->name() != name) { 1589 break; 1590 } 1591 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) { 1592 return i; 1593 } 1594 } 1595 // search upwards 1596 for (i = hit + 1; i < methods->length(); ++i) { 1597 const Method* const m = methods->at(i); 1598 assert(m->is_method(), "must be method"); 1599 if (m->name() != name) { 1600 break; 1601 } 1602 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) { 1603 return i; 1604 } 1605 } 1606 // not found 1607 #ifdef ASSERT 1608 const int index = (skipping_overpass || skipping_static || skipping_private) ? -1 : 1609 linear_search(methods, name, signature); 1610 assert(-1 == index, "binary search should have found entry %d", index); 1611 #endif 1612 } 1613 return -1; 1614 } 1615 1616 int InstanceKlass::find_method_by_name(const Symbol* name, int* end) const { 1617 return find_method_by_name(methods(), name, end); 1618 } 1619 1620 int InstanceKlass::find_method_by_name(const Array<Method*>* methods, 1621 const Symbol* name, 1622 int* end_ptr) { 1623 assert(end_ptr != NULL, "just checking"); 1624 int start = binary_search(methods, name); 1625 int end = start + 1; 1626 if (start != -1) { 1627 while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start; 1628 while (end < methods->length() && (methods->at(end))->name() == name) ++end; 1629 *end_ptr = end; 1630 return start; 1631 } 1632 return -1; 1633 } 1634 1635 // uncached_lookup_method searches both the local class methods array and all 1636 // superclasses methods arrays, skipping any overpass methods in superclasses. 1637 Method* InstanceKlass::uncached_lookup_method(const Symbol* name, 1638 const Symbol* signature, 1639 OverpassLookupMode overpass_mode) const { 1640 OverpassLookupMode overpass_local_mode = overpass_mode; 1641 const Klass* klass = this; 1642 while (klass != NULL) { 1643 Method* const method = InstanceKlass::cast(klass)->find_method_impl(name, 1644 signature, 1645 overpass_local_mode, 1646 find_static, 1647 find_private); 1648 if (method != NULL) { 1649 return method; 1650 } 1651 klass = klass->super(); 1652 overpass_local_mode = skip_overpass; // Always ignore overpass methods in superclasses 1653 } 1654 return NULL; 1655 } 1656 1657 #ifdef ASSERT 1658 // search through class hierarchy and return true if this class or 1659 // one of the superclasses was redefined 1660 bool InstanceKlass::has_redefined_this_or_super() const { 1661 const Klass* klass = this; 1662 while (klass != NULL) { 1663 if (InstanceKlass::cast(klass)->has_been_redefined()) { 1664 return true; 1665 } 1666 klass = klass->super(); 1667 } 1668 return false; 1669 } 1670 #endif 1671 1672 // lookup a method in the default methods list then in all transitive interfaces 1673 // Do NOT return private or static methods 1674 Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name, 1675 Symbol* signature) const { 1676 Method* m = NULL; 1677 if (default_methods() != NULL) { 1678 m = find_method(default_methods(), name, signature); 1679 } 1680 // Look up interfaces 1681 if (m == NULL) { 1682 m = lookup_method_in_all_interfaces(name, signature, find_defaults); 1683 } 1684 return m; 1685 } 1686 1687 // lookup a method in all the interfaces that this class implements 1688 // Do NOT return private or static methods, new in JDK8 which are not externally visible 1689 // They should only be found in the initial InterfaceMethodRef 1690 Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name, 1691 Symbol* signature, 1692 DefaultsLookupMode defaults_mode) const { 1693 Array<Klass*>* all_ifs = transitive_interfaces(); 1694 int num_ifs = all_ifs->length(); 1695 InstanceKlass *ik = NULL; 1696 for (int i = 0; i < num_ifs; i++) { 1697 ik = InstanceKlass::cast(all_ifs->at(i)); 1698 Method* m = ik->lookup_method(name, signature); 1699 if (m != NULL && m->is_public() && !m->is_static() && 1700 ((defaults_mode != skip_defaults) || !m->is_default_method())) { 1701 return m; 1702 } 1703 } 1704 return NULL; 1705 } 1706 1707 /* jni_id_for_impl for jfieldIds only */ 1708 JNIid* InstanceKlass::jni_id_for_impl(int offset) { 1709 MutexLocker ml(JfieldIdCreation_lock); 1710 // Retry lookup after we got the lock 1711 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset); 1712 if (probe == NULL) { 1713 // Slow case, allocate new static field identifier 1714 probe = new JNIid(this, offset, jni_ids()); 1715 set_jni_ids(probe); 1716 } 1717 return probe; 1718 } 1719 1720 1721 /* jni_id_for for jfieldIds only */ 1722 JNIid* InstanceKlass::jni_id_for(int offset) { 1723 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset); 1724 if (probe == NULL) { 1725 probe = jni_id_for_impl(offset); 1726 } 1727 return probe; 1728 } 1729 1730 u2 InstanceKlass::enclosing_method_data(int offset) const { 1731 const Array<jushort>* const inner_class_list = inner_classes(); 1732 if (inner_class_list == NULL) { 1733 return 0; 1734 } 1735 const int length = inner_class_list->length(); 1736 if (length % inner_class_next_offset == 0) { 1737 return 0; 1738 } 1739 const int index = length - enclosing_method_attribute_size; 1740 assert(offset < enclosing_method_attribute_size, "invalid offset"); 1741 return inner_class_list->at(index + offset); 1742 } 1743 1744 void InstanceKlass::set_enclosing_method_indices(u2 class_index, 1745 u2 method_index) { 1746 Array<jushort>* inner_class_list = inner_classes(); 1747 assert (inner_class_list != NULL, "_inner_classes list is not set up"); 1748 int length = inner_class_list->length(); 1749 if (length % inner_class_next_offset == enclosing_method_attribute_size) { 1750 int index = length - enclosing_method_attribute_size; 1751 inner_class_list->at_put( 1752 index + enclosing_method_class_index_offset, class_index); 1753 inner_class_list->at_put( 1754 index + enclosing_method_method_index_offset, method_index); 1755 } 1756 } 1757 1758 // Lookup or create a jmethodID. 1759 // This code is called by the VMThread and JavaThreads so the 1760 // locking has to be done very carefully to avoid deadlocks 1761 // and/or other cache consistency problems. 1762 // 1763 jmethodID InstanceKlass::get_jmethod_id(const methodHandle& method_h) { 1764 size_t idnum = (size_t)method_h->method_idnum(); 1765 jmethodID* jmeths = methods_jmethod_ids_acquire(); 1766 size_t length = 0; 1767 jmethodID id = NULL; 1768 1769 // We use a double-check locking idiom here because this cache is 1770 // performance sensitive. In the normal system, this cache only 1771 // transitions from NULL to non-NULL which is safe because we use 1772 // release_set_methods_jmethod_ids() to advertise the new cache. 1773 // A partially constructed cache should never be seen by a racing 1774 // thread. We also use release_store_ptr() to save a new jmethodID 1775 // in the cache so a partially constructed jmethodID should never be 1776 // seen either. Cache reads of existing jmethodIDs proceed without a 1777 // lock, but cache writes of a new jmethodID requires uniqueness and 1778 // creation of the cache itself requires no leaks so a lock is 1779 // generally acquired in those two cases. 1780 // 1781 // If the RedefineClasses() API has been used, then this cache can 1782 // grow and we'll have transitions from non-NULL to bigger non-NULL. 1783 // Cache creation requires no leaks and we require safety between all 1784 // cache accesses and freeing of the old cache so a lock is generally 1785 // acquired when the RedefineClasses() API has been used. 1786 1787 if (jmeths != NULL) { 1788 // the cache already exists 1789 if (!idnum_can_increment()) { 1790 // the cache can't grow so we can just get the current values 1791 get_jmethod_id_length_value(jmeths, idnum, &length, &id); 1792 } else { 1793 // cache can grow so we have to be more careful 1794 if (Threads::number_of_threads() == 0 || 1795 SafepointSynchronize::is_at_safepoint()) { 1796 // we're single threaded or at a safepoint - no locking needed 1797 get_jmethod_id_length_value(jmeths, idnum, &length, &id); 1798 } else { 1799 MutexLocker ml(JmethodIdCreation_lock); 1800 get_jmethod_id_length_value(jmeths, idnum, &length, &id); 1801 } 1802 } 1803 } 1804 // implied else: 1805 // we need to allocate a cache so default length and id values are good 1806 1807 if (jmeths == NULL || // no cache yet 1808 length <= idnum || // cache is too short 1809 id == NULL) { // cache doesn't contain entry 1810 1811 // This function can be called by the VMThread so we have to do all 1812 // things that might block on a safepoint before grabbing the lock. 1813 // Otherwise, we can deadlock with the VMThread or have a cache 1814 // consistency issue. These vars keep track of what we might have 1815 // to free after the lock is dropped. 1816 jmethodID to_dealloc_id = NULL; 1817 jmethodID* to_dealloc_jmeths = NULL; 1818 1819 // may not allocate new_jmeths or use it if we allocate it 1820 jmethodID* new_jmeths = NULL; 1821 if (length <= idnum) { 1822 // allocate a new cache that might be used 1823 size_t size = MAX2(idnum+1, (size_t)idnum_allocated_count()); 1824 new_jmeths = NEW_C_HEAP_ARRAY(jmethodID, size+1, mtClass); 1825 memset(new_jmeths, 0, (size+1)*sizeof(jmethodID)); 1826 // cache size is stored in element[0], other elements offset by one 1827 new_jmeths[0] = (jmethodID)size; 1828 } 1829 1830 // allocate a new jmethodID that might be used 1831 jmethodID new_id = NULL; 1832 if (method_h->is_old() && !method_h->is_obsolete()) { 1833 // The method passed in is old (but not obsolete), we need to use the current version 1834 Method* current_method = method_with_idnum((int)idnum); 1835 assert(current_method != NULL, "old and but not obsolete, so should exist"); 1836 new_id = Method::make_jmethod_id(class_loader_data(), current_method); 1837 } else { 1838 // It is the current version of the method or an obsolete method, 1839 // use the version passed in 1840 new_id = Method::make_jmethod_id(class_loader_data(), method_h()); 1841 } 1842 1843 if (Threads::number_of_threads() == 0 || 1844 SafepointSynchronize::is_at_safepoint()) { 1845 // we're single threaded or at a safepoint - no locking needed 1846 id = get_jmethod_id_fetch_or_update(idnum, new_id, new_jmeths, 1847 &to_dealloc_id, &to_dealloc_jmeths); 1848 } else { 1849 MutexLocker ml(JmethodIdCreation_lock); 1850 id = get_jmethod_id_fetch_or_update(idnum, new_id, new_jmeths, 1851 &to_dealloc_id, &to_dealloc_jmeths); 1852 } 1853 1854 // The lock has been dropped so we can free resources. 1855 // Free up either the old cache or the new cache if we allocated one. 1856 if (to_dealloc_jmeths != NULL) { 1857 FreeHeap(to_dealloc_jmeths); 1858 } 1859 // free up the new ID since it wasn't needed 1860 if (to_dealloc_id != NULL) { 1861 Method::destroy_jmethod_id(class_loader_data(), to_dealloc_id); 1862 } 1863 } 1864 return id; 1865 } 1866 1867 // Figure out how many jmethodIDs haven't been allocated, and make 1868 // sure space for them is pre-allocated. This makes getting all 1869 // method ids much, much faster with classes with more than 8 1870 // methods, and has a *substantial* effect on performance with jvmti 1871 // code that loads all jmethodIDs for all classes. 1872 void InstanceKlass::ensure_space_for_methodids(int start_offset) { 1873 int new_jmeths = 0; 1874 int length = methods()->length(); 1875 for (int index = start_offset; index < length; index++) { 1876 Method* m = methods()->at(index); 1877 jmethodID id = m->find_jmethod_id_or_null(); 1878 if (id == NULL) { 1879 new_jmeths++; 1880 } 1881 } 1882 if (new_jmeths != 0) { 1883 Method::ensure_jmethod_ids(class_loader_data(), new_jmeths); 1884 } 1885 } 1886 1887 // Common code to fetch the jmethodID from the cache or update the 1888 // cache with the new jmethodID. This function should never do anything 1889 // that causes the caller to go to a safepoint or we can deadlock with 1890 // the VMThread or have cache consistency issues. 1891 // 1892 jmethodID InstanceKlass::get_jmethod_id_fetch_or_update( 1893 size_t idnum, jmethodID new_id, 1894 jmethodID* new_jmeths, jmethodID* to_dealloc_id_p, 1895 jmethodID** to_dealloc_jmeths_p) { 1896 assert(new_id != NULL, "sanity check"); 1897 assert(to_dealloc_id_p != NULL, "sanity check"); 1898 assert(to_dealloc_jmeths_p != NULL, "sanity check"); 1899 assert(Threads::number_of_threads() == 0 || 1900 SafepointSynchronize::is_at_safepoint() || 1901 JmethodIdCreation_lock->owned_by_self(), "sanity check"); 1902 1903 // reacquire the cache - we are locked, single threaded or at a safepoint 1904 jmethodID* jmeths = methods_jmethod_ids_acquire(); 1905 jmethodID id = NULL; 1906 size_t length = 0; 1907 1908 if (jmeths == NULL || // no cache yet 1909 (length = (size_t)jmeths[0]) <= idnum) { // cache is too short 1910 if (jmeths != NULL) { 1911 // copy any existing entries from the old cache 1912 for (size_t index = 0; index < length; index++) { 1913 new_jmeths[index+1] = jmeths[index+1]; 1914 } 1915 *to_dealloc_jmeths_p = jmeths; // save old cache for later delete 1916 } 1917 release_set_methods_jmethod_ids(jmeths = new_jmeths); 1918 } else { 1919 // fetch jmethodID (if any) from the existing cache 1920 id = jmeths[idnum+1]; 1921 *to_dealloc_jmeths_p = new_jmeths; // save new cache for later delete 1922 } 1923 if (id == NULL) { 1924 // No matching jmethodID in the existing cache or we have a new 1925 // cache or we just grew the cache. This cache write is done here 1926 // by the first thread to win the foot race because a jmethodID 1927 // needs to be unique once it is generally available. 1928 id = new_id; 1929 1930 // The jmethodID cache can be read while unlocked so we have to 1931 // make sure the new jmethodID is complete before installing it 1932 // in the cache. 1933 OrderAccess::release_store_ptr(&jmeths[idnum+1], id); 1934 } else { 1935 *to_dealloc_id_p = new_id; // save new id for later delete 1936 } 1937 return id; 1938 } 1939 1940 1941 // Common code to get the jmethodID cache length and the jmethodID 1942 // value at index idnum if there is one. 1943 // 1944 void InstanceKlass::get_jmethod_id_length_value(jmethodID* cache, 1945 size_t idnum, size_t *length_p, jmethodID* id_p) { 1946 assert(cache != NULL, "sanity check"); 1947 assert(length_p != NULL, "sanity check"); 1948 assert(id_p != NULL, "sanity check"); 1949 1950 // cache size is stored in element[0], other elements offset by one 1951 *length_p = (size_t)cache[0]; 1952 if (*length_p <= idnum) { // cache is too short 1953 *id_p = NULL; 1954 } else { 1955 *id_p = cache[idnum+1]; // fetch jmethodID (if any) 1956 } 1957 } 1958 1959 1960 // Lookup a jmethodID, NULL if not found. Do no blocking, no allocations, no handles 1961 jmethodID InstanceKlass::jmethod_id_or_null(Method* method) { 1962 size_t idnum = (size_t)method->method_idnum(); 1963 jmethodID* jmeths = methods_jmethod_ids_acquire(); 1964 size_t length; // length assigned as debugging crumb 1965 jmethodID id = NULL; 1966 if (jmeths != NULL && // If there is a cache 1967 (length = (size_t)jmeths[0]) > idnum) { // and if it is long enough, 1968 id = jmeths[idnum+1]; // Look up the id (may be NULL) 1969 } 1970 return id; 1971 } 1972 1973 inline DependencyContext InstanceKlass::dependencies() { 1974 DependencyContext dep_context(&_dep_context); 1975 return dep_context; 1976 } 1977 1978 int InstanceKlass::mark_dependent_nmethods(KlassDepChange& changes) { 1979 return dependencies().mark_dependent_nmethods(changes); 1980 } 1981 1982 void InstanceKlass::add_dependent_nmethod(nmethod* nm) { 1983 dependencies().add_dependent_nmethod(nm); 1984 } 1985 1986 void InstanceKlass::remove_dependent_nmethod(nmethod* nm, bool delete_immediately) { 1987 dependencies().remove_dependent_nmethod(nm, delete_immediately); 1988 } 1989 1990 #ifndef PRODUCT 1991 void InstanceKlass::print_dependent_nmethods(bool verbose) { 1992 dependencies().print_dependent_nmethods(verbose); 1993 } 1994 1995 bool InstanceKlass::is_dependent_nmethod(nmethod* nm) { 1996 return dependencies().is_dependent_nmethod(nm); 1997 } 1998 #endif //PRODUCT 1999 2000 void InstanceKlass::clean_weak_instanceklass_links(BoolObjectClosure* is_alive) { 2001 clean_implementors_list(is_alive); 2002 clean_method_data(is_alive); 2003 2004 // Since GC iterates InstanceKlasses sequentially, it is safe to remove stale entries here. 2005 DependencyContext dep_context(&_dep_context); 2006 dep_context.expunge_stale_entries(); 2007 } 2008 2009 void InstanceKlass::clean_implementors_list(BoolObjectClosure* is_alive) { 2010 assert(class_loader_data()->is_alive(is_alive), "this klass should be live"); 2011 if (is_interface()) { 2012 if (ClassUnloading) { 2013 Klass* impl = implementor(); 2014 if (impl != NULL) { 2015 if (!impl->is_loader_alive(is_alive)) { 2016 // remove this guy 2017 Klass** klass = adr_implementor(); 2018 assert(klass != NULL, "null klass"); 2019 if (klass != NULL) { 2020 *klass = NULL; 2021 } 2022 } 2023 } 2024 } 2025 } 2026 } 2027 2028 void InstanceKlass::clean_method_data(BoolObjectClosure* is_alive) { 2029 for (int m = 0; m < methods()->length(); m++) { 2030 MethodData* mdo = methods()->at(m)->method_data(); 2031 if (mdo != NULL) { 2032 mdo->clean_method_data(is_alive); 2033 } 2034 } 2035 } 2036 2037 bool InstanceKlass::supers_have_passed_fingerprint_checks() { 2038 if (java_super() != NULL && !java_super()->has_passed_fingerprint_check()) { 2039 ResourceMark rm; 2040 log_trace(class, fingerprint)("%s : super %s not fingerprinted", external_name(), java_super()->external_name()); 2041 return false; 2042 } 2043 2044 Array<Klass*>* local_interfaces = this->local_interfaces(); 2045 if (local_interfaces != NULL) { 2046 int length = local_interfaces->length(); 2047 for (int i = 0; i < length; i++) { 2048 InstanceKlass* intf = InstanceKlass::cast(local_interfaces->at(i)); 2049 if (!intf->has_passed_fingerprint_check()) { 2050 ResourceMark rm; 2051 log_trace(class, fingerprint)("%s : interface %s not fingerprinted", external_name(), intf->external_name()); 2052 return false; 2053 } 2054 } 2055 } 2056 2057 return true; 2058 } 2059 2060 bool InstanceKlass::should_store_fingerprint() { 2061 #if INCLUDE_AOT 2062 // We store the fingerprint into the InstanceKlass only in the following 2 cases: 2063 if (EnableJVMCI && !UseJVMCICompiler) { 2064 // (1) We are running AOT to generate a shared library. 2065 return true; 2066 } 2067 if (DumpSharedSpaces) { 2068 // (2) We are running -Xshare:dump to create a shared archive 2069 return true; 2070 } 2071 #endif 2072 2073 // In all other cases we might set the _misc_has_passed_fingerprint_check bit, 2074 // but do not store the 64-bit fingerprint to save space. 2075 return false; 2076 } 2077 2078 bool InstanceKlass::has_stored_fingerprint() const { 2079 #if INCLUDE_AOT 2080 return should_store_fingerprint() || is_shared(); 2081 #else 2082 return false; 2083 #endif 2084 } 2085 2086 uint64_t InstanceKlass::get_stored_fingerprint() const { 2087 address adr = adr_fingerprint(); 2088 if (adr != NULL) { 2089 return (uint64_t)Bytes::get_native_u8(adr); // adr may not be 64-bit aligned 2090 } 2091 return 0; 2092 } 2093 2094 void InstanceKlass::store_fingerprint(uint64_t fingerprint) { 2095 address adr = adr_fingerprint(); 2096 if (adr != NULL) { 2097 Bytes::put_native_u8(adr, (u8)fingerprint); // adr may not be 64-bit aligned 2098 2099 ResourceMark rm; 2100 log_trace(class, fingerprint)("stored as " PTR64_FORMAT " for class %s", fingerprint, external_name()); 2101 } 2102 } 2103 2104 static void remove_unshareable_in_class(Klass* k) { 2105 // remove klass's unshareable info 2106 k->remove_unshareable_info(); 2107 } 2108 2109 void InstanceKlass::remove_unshareable_info() { 2110 Klass::remove_unshareable_info(); 2111 // Unlink the class 2112 if (is_linked()) { 2113 unlink_class(); 2114 } 2115 init_implementor(); 2116 2117 constants()->remove_unshareable_info(); 2118 2119 assert(_dep_context == DependencyContext::EMPTY, "dependency context is not shareable"); 2120 2121 for (int i = 0; i < methods()->length(); i++) { 2122 Method* m = methods()->at(i); 2123 m->remove_unshareable_info(); 2124 } 2125 2126 // do array classes also. 2127 array_klasses_do(remove_unshareable_in_class); 2128 } 2129 2130 static void restore_unshareable_in_class(Klass* k, TRAPS) { 2131 // Array classes have null protection domain. 2132 // --> see ArrayKlass::complete_create_array_klass() 2133 k->restore_unshareable_info(ClassLoaderData::the_null_class_loader_data(), Handle(), CHECK); 2134 } 2135 2136 void InstanceKlass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain, TRAPS) { 2137 set_package(loader_data, CHECK); 2138 Klass::restore_unshareable_info(loader_data, protection_domain, CHECK); 2139 2140 Array<Method*>* methods = this->methods(); 2141 int num_methods = methods->length(); 2142 for (int index2 = 0; index2 < num_methods; ++index2) { 2143 methodHandle m(THREAD, methods->at(index2)); 2144 m->restore_unshareable_info(CHECK); 2145 } 2146 if (JvmtiExport::has_redefined_a_class()) { 2147 // Reinitialize vtable because RedefineClasses may have changed some 2148 // entries in this vtable for super classes so the CDS vtable might 2149 // point to old or obsolete entries. RedefineClasses doesn't fix up 2150 // vtables in the shared system dictionary, only the main one. 2151 // It also redefines the itable too so fix that too. 2152 ResourceMark rm(THREAD); 2153 vtable().initialize_vtable(false, CHECK); 2154 itable().initialize_itable(false, CHECK); 2155 } 2156 2157 // restore constant pool resolved references 2158 constants()->restore_unshareable_info(CHECK); 2159 2160 array_klasses_do(restore_unshareable_in_class, CHECK); 2161 } 2162 2163 // returns true IFF is_in_error_state() has been changed as a result of this call. 2164 bool InstanceKlass::check_sharing_error_state() { 2165 assert(DumpSharedSpaces, "should only be called during dumping"); 2166 bool old_state = is_in_error_state(); 2167 2168 if (!is_in_error_state()) { 2169 bool bad = false; 2170 for (InstanceKlass* sup = java_super(); sup; sup = sup->java_super()) { 2171 if (sup->is_in_error_state()) { 2172 bad = true; 2173 break; 2174 } 2175 } 2176 if (!bad) { 2177 Array<Klass*>* interfaces = transitive_interfaces(); 2178 for (int i = 0; i < interfaces->length(); i++) { 2179 Klass* iface = interfaces->at(i); 2180 if (InstanceKlass::cast(iface)->is_in_error_state()) { 2181 bad = true; 2182 break; 2183 } 2184 } 2185 } 2186 2187 if (bad) { 2188 set_in_error_state(); 2189 } 2190 } 2191 2192 return (old_state != is_in_error_state()); 2193 } 2194 2195 #if INCLUDE_JVMTI 2196 static void clear_all_breakpoints(Method* m) { 2197 m->clear_all_breakpoints(); 2198 } 2199 #endif 2200 2201 void InstanceKlass::notify_unload_class(InstanceKlass* ik) { 2202 // notify the debugger 2203 if (JvmtiExport::should_post_class_unload()) { 2204 JvmtiExport::post_class_unload(ik); 2205 } 2206 2207 // notify ClassLoadingService of class unload 2208 ClassLoadingService::notify_class_unloaded(ik); 2209 } 2210 2211 void InstanceKlass::release_C_heap_structures(InstanceKlass* ik) { 2212 // Clean up C heap 2213 ik->release_C_heap_structures(); 2214 ik->constants()->release_C_heap_structures(); 2215 } 2216 2217 void InstanceKlass::release_C_heap_structures() { 2218 // Can't release the constant pool here because the constant pool can be 2219 // deallocated separately from the InstanceKlass for default methods and 2220 // redefine classes. 2221 2222 // Deallocate oop map cache 2223 if (_oop_map_cache != NULL) { 2224 delete _oop_map_cache; 2225 _oop_map_cache = NULL; 2226 } 2227 2228 // Deallocate JNI identifiers for jfieldIDs 2229 JNIid::deallocate(jni_ids()); 2230 set_jni_ids(NULL); 2231 2232 jmethodID* jmeths = methods_jmethod_ids_acquire(); 2233 if (jmeths != (jmethodID*)NULL) { 2234 release_set_methods_jmethod_ids(NULL); 2235 FreeHeap(jmeths); 2236 } 2237 2238 // Deallocate MemberNameTable 2239 { 2240 Mutex* lock_or_null = SafepointSynchronize::is_at_safepoint() ? NULL : MemberNameTable_lock; 2241 MutexLockerEx ml(lock_or_null, Mutex::_no_safepoint_check_flag); 2242 MemberNameTable* mnt = member_names(); 2243 if (mnt != NULL) { 2244 delete mnt; 2245 set_member_names(NULL); 2246 } 2247 } 2248 2249 // Release dependencies. 2250 // It is desirable to use DC::remove_all_dependents() here, but, unfortunately, 2251 // it is not safe (see JDK-8143408). The problem is that the klass dependency 2252 // context can contain live dependencies, since there's a race between nmethod & 2253 // klass unloading. If the klass is dead when nmethod unloading happens, relevant 2254 // dependencies aren't removed from the context associated with the class (see 2255 // nmethod::flush_dependencies). It ends up during klass unloading as seemingly 2256 // live dependencies pointing to unloaded nmethods and causes a crash in 2257 // DC::remove_all_dependents() when it touches unloaded nmethod. 2258 dependencies().wipe(); 2259 2260 #if INCLUDE_JVMTI 2261 // Deallocate breakpoint records 2262 if (breakpoints() != 0x0) { 2263 methods_do(clear_all_breakpoints); 2264 assert(breakpoints() == 0x0, "should have cleared breakpoints"); 2265 } 2266 2267 // deallocate the cached class file 2268 if (_cached_class_file != NULL && !MetaspaceShared::is_in_shared_space(_cached_class_file)) { 2269 os::free(_cached_class_file); 2270 _cached_class_file = NULL; 2271 } 2272 #endif 2273 2274 // Decrement symbol reference counts associated with the unloaded class. 2275 if (_name != NULL) _name->decrement_refcount(); 2276 // unreference array name derived from this class name (arrays of an unloaded 2277 // class can't be referenced anymore). 2278 if (_array_name != NULL) _array_name->decrement_refcount(); 2279 if (_source_debug_extension != NULL) FREE_C_HEAP_ARRAY(char, _source_debug_extension); 2280 2281 assert(_total_instanceKlass_count >= 1, "Sanity check"); 2282 Atomic::dec(&_total_instanceKlass_count); 2283 } 2284 2285 void InstanceKlass::set_source_debug_extension(const char* array, int length) { 2286 if (array == NULL) { 2287 _source_debug_extension = NULL; 2288 } else { 2289 // Adding one to the attribute length in order to store a null terminator 2290 // character could cause an overflow because the attribute length is 2291 // already coded with an u4 in the classfile, but in practice, it's 2292 // unlikely to happen. 2293 assert((length+1) > length, "Overflow checking"); 2294 char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass); 2295 for (int i = 0; i < length; i++) { 2296 sde[i] = array[i]; 2297 } 2298 sde[length] = '\0'; 2299 _source_debug_extension = sde; 2300 } 2301 } 2302 2303 address InstanceKlass::static_field_addr(int offset) { 2304 return (address)(offset + InstanceMirrorKlass::offset_of_static_fields() + cast_from_oop<intptr_t>(java_mirror())); 2305 } 2306 2307 2308 const char* InstanceKlass::signature_name() const { 2309 int hash_len = 0; 2310 char hash_buf[40]; 2311 2312 // If this is an anonymous class, append a hash to make the name unique 2313 if (is_anonymous()) { 2314 intptr_t hash = (java_mirror() != NULL) ? java_mirror()->identity_hash() : 0; 2315 jio_snprintf(hash_buf, sizeof(hash_buf), "/" UINTX_FORMAT, (uintx)hash); 2316 hash_len = (int)strlen(hash_buf); 2317 } 2318 2319 // Get the internal name as a c string 2320 const char* src = (const char*) (name()->as_C_string()); 2321 const int src_length = (int)strlen(src); 2322 2323 char* dest = NEW_RESOURCE_ARRAY(char, src_length + hash_len + 3); 2324 2325 // Add L as type indicator 2326 int dest_index = 0; 2327 dest[dest_index++] = is_value_type_klass() ? 'Q' : 'L'; 2328 2329 // Add the actual class name 2330 for (int src_index = 0; src_index < src_length; ) { 2331 dest[dest_index++] = src[src_index++]; 2332 } 2333 2334 // If we have a hash, append it 2335 for (int hash_index = 0; hash_index < hash_len; ) { 2336 dest[dest_index++] = hash_buf[hash_index++]; 2337 } 2338 2339 // Add the semicolon and the NULL 2340 dest[dest_index++] = ';'; 2341 dest[dest_index] = '\0'; 2342 return dest; 2343 } 2344 2345 // Used to obtain the package name from a fully qualified class name. 2346 Symbol* InstanceKlass::package_from_name(const Symbol* name, TRAPS) { 2347 if (name == NULL) { 2348 return NULL; 2349 } else { 2350 if (name->utf8_length() <= 0) { 2351 return NULL; 2352 } 2353 ResourceMark rm; 2354 const char* package_name = ClassLoader::package_from_name((const char*) name->as_C_string()); 2355 if (package_name == NULL) { 2356 return NULL; 2357 } 2358 Symbol* pkg_name = SymbolTable::new_symbol(package_name, THREAD); 2359 return pkg_name; 2360 } 2361 } 2362 2363 ModuleEntry* InstanceKlass::module() const { 2364 if (!in_unnamed_package()) { 2365 return _package_entry->module(); 2366 } 2367 const Klass* host = host_klass(); 2368 if (host == NULL) { 2369 return class_loader_data()->unnamed_module(); 2370 } 2371 return host->class_loader_data()->unnamed_module(); 2372 } 2373 2374 void InstanceKlass::set_package(ClassLoaderData* loader_data, TRAPS) { 2375 2376 // ensure java/ packages only loaded by boot or platform builtin loaders 2377 Handle class_loader(THREAD, loader_data->class_loader()); 2378 check_prohibited_package(name(), class_loader, CHECK); 2379 2380 TempNewSymbol pkg_name = package_from_name(name(), CHECK); 2381 2382 if (pkg_name != NULL && loader_data != NULL) { 2383 2384 // Find in class loader's package entry table. 2385 _package_entry = loader_data->packages()->lookup_only(pkg_name); 2386 2387 // If the package name is not found in the loader's package 2388 // entry table, it is an indication that the package has not 2389 // been defined. Consider it defined within the unnamed module. 2390 if (_package_entry == NULL) { 2391 ResourceMark rm; 2392 2393 if (!ModuleEntryTable::javabase_defined()) { 2394 // Before java.base is defined during bootstrapping, define all packages in 2395 // the java.base module. If a non-java.base package is erroneously placed 2396 // in the java.base module it will be caught later when java.base 2397 // is defined by ModuleEntryTable::verify_javabase_packages check. 2398 assert(ModuleEntryTable::javabase_moduleEntry() != NULL, JAVA_BASE_NAME " module is NULL"); 2399 _package_entry = loader_data->packages()->lookup(pkg_name, ModuleEntryTable::javabase_moduleEntry()); 2400 } else { 2401 assert(loader_data->unnamed_module() != NULL, "unnamed module is NULL"); 2402 _package_entry = loader_data->packages()->lookup(pkg_name, 2403 loader_data->unnamed_module()); 2404 } 2405 2406 // A package should have been successfully created 2407 assert(_package_entry != NULL, "Package entry for class %s not found, loader %s", 2408 name()->as_C_string(), loader_data->loader_name()); 2409 } 2410 2411 if (log_is_enabled(Debug, module)) { 2412 ResourceMark rm; 2413 ModuleEntry* m = _package_entry->module(); 2414 log_trace(module)("Setting package: class: %s, package: %s, loader: %s, module: %s", 2415 external_name(), 2416 pkg_name->as_C_string(), 2417 loader_data->loader_name(), 2418 (m->is_named() ? m->name()->as_C_string() : UNNAMED_MODULE)); 2419 } 2420 } else { 2421 ResourceMark rm; 2422 log_trace(module)("Setting package: class: %s, package: unnamed, loader: %s, module: %s", 2423 external_name(), 2424 (loader_data != NULL) ? loader_data->loader_name() : "NULL", 2425 UNNAMED_MODULE); 2426 } 2427 } 2428 2429 2430 // different versions of is_same_class_package 2431 2432 bool InstanceKlass::is_same_class_package(const Klass* class2) const { 2433 oop classloader1 = this->class_loader(); 2434 PackageEntry* classpkg1 = this->package(); 2435 if (class2->is_objArray_klass()) { 2436 class2 = ObjArrayKlass::cast(class2)->bottom_klass(); 2437 } 2438 2439 oop classloader2; 2440 PackageEntry* classpkg2; 2441 if (class2->is_instance_klass()) { 2442 classloader2 = class2->class_loader(); 2443 classpkg2 = class2->package(); 2444 } else { 2445 assert(class2->is_typeArray_klass(), "should be type array"); 2446 classloader2 = NULL; 2447 classpkg2 = NULL; 2448 } 2449 2450 // Same package is determined by comparing class loader 2451 // and package entries. Both must be the same. This rule 2452 // applies even to classes that are defined in the unnamed 2453 // package, they still must have the same class loader. 2454 if ((classloader1 == classloader2) && (classpkg1 == classpkg2)) { 2455 return true; 2456 } 2457 2458 return false; 2459 } 2460 2461 bool InstanceKlass::is_same_class_package(oop other_class_loader, 2462 const Symbol* other_class_name) const { 2463 oop this_class_loader = class_loader(); 2464 const Symbol* const this_class_name = name(); 2465 2466 return InstanceKlass::is_same_class_package(this_class_loader, 2467 this_class_name, 2468 other_class_loader, 2469 other_class_name); 2470 } 2471 2472 // return true if two classes are in the same package, classloader 2473 // and classname information is enough to determine a class's package 2474 bool InstanceKlass::is_same_class_package(oop class_loader1, const Symbol* class_name1, 2475 oop class_loader2, const Symbol* class_name2) { 2476 if (class_loader1 != class_loader2) { 2477 return false; 2478 } else if (class_name1 == class_name2) { 2479 return true; 2480 } else { 2481 ResourceMark rm; 2482 2483 bool bad_class_name = false; 2484 const char* name1 = ClassLoader::package_from_name((const char*) class_name1->as_C_string(), &bad_class_name); 2485 if (bad_class_name) { 2486 return false; 2487 } 2488 2489 const char* name2 = ClassLoader::package_from_name((const char*) class_name2->as_C_string(), &bad_class_name); 2490 if (bad_class_name) { 2491 return false; 2492 } 2493 2494 if ((name1 == NULL) || (name2 == NULL)) { 2495 // One of the two doesn't have a package. Only return true 2496 // if the other one also doesn't have a package. 2497 return name1 == name2; 2498 } 2499 2500 // Check that package is identical 2501 return (strcmp(name1, name2) == 0); 2502 } 2503 } 2504 2505 // Returns true iff super_method can be overridden by a method in targetclassname 2506 // See JLS 3rd edition 8.4.6.1 2507 // Assumes name-signature match 2508 // "this" is InstanceKlass of super_method which must exist 2509 // note that the InstanceKlass of the method in the targetclassname has not always been created yet 2510 bool InstanceKlass::is_override(const methodHandle& super_method, Handle targetclassloader, Symbol* targetclassname, TRAPS) { 2511 // Private methods can not be overridden 2512 if (super_method->is_private()) { 2513 return false; 2514 } 2515 // If super method is accessible, then override 2516 if ((super_method->is_protected()) || 2517 (super_method->is_public())) { 2518 return true; 2519 } 2520 // Package-private methods are not inherited outside of package 2521 assert(super_method->is_package_private(), "must be package private"); 2522 return(is_same_class_package(targetclassloader(), targetclassname)); 2523 } 2524 2525 // Only boot and platform class loaders can define classes in "java/" packages. 2526 void InstanceKlass::check_prohibited_package(Symbol* class_name, 2527 Handle class_loader, 2528 TRAPS) { 2529 if (!class_loader.is_null() && 2530 !SystemDictionary::is_platform_class_loader(class_loader()) && 2531 class_name != NULL) { 2532 ResourceMark rm(THREAD); 2533 char* name = class_name->as_C_string(); 2534 if (strncmp(name, JAVAPKG, JAVAPKG_LEN) == 0 && name[JAVAPKG_LEN] == '/') { 2535 TempNewSymbol pkg_name = InstanceKlass::package_from_name(class_name, CHECK); 2536 assert(pkg_name != NULL, "Error in parsing package name starting with 'java/'"); 2537 name = pkg_name->as_C_string(); 2538 const char* class_loader_name = SystemDictionary::loader_name(class_loader()); 2539 StringUtils::replace_no_expand(name, "/", "."); 2540 const char* msg_text1 = "Class loader (instance of): "; 2541 const char* msg_text2 = " tried to load prohibited package name: "; 2542 size_t len = strlen(msg_text1) + strlen(class_loader_name) + strlen(msg_text2) + strlen(name) + 1; 2543 char* message = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, len); 2544 jio_snprintf(message, len, "%s%s%s%s", msg_text1, class_loader_name, msg_text2, name); 2545 THROW_MSG(vmSymbols::java_lang_SecurityException(), message); 2546 } 2547 } 2548 return; 2549 } 2550 2551 // tell if two classes have the same enclosing class (at package level) 2552 bool InstanceKlass::is_same_package_member(const Klass* class2, TRAPS) const { 2553 if (class2 == this) return true; 2554 if (!class2->is_instance_klass()) return false; 2555 2556 // must be in same package before we try anything else 2557 if (!is_same_class_package(class2)) 2558 return false; 2559 2560 // As long as there is an outer_this.getEnclosingClass, 2561 // shift the search outward. 2562 const InstanceKlass* outer_this = this; 2563 for (;;) { 2564 // As we walk along, look for equalities between outer_this and class2. 2565 // Eventually, the walks will terminate as outer_this stops 2566 // at the top-level class around the original class. 2567 bool ignore_inner_is_member; 2568 const Klass* next = outer_this->compute_enclosing_class(&ignore_inner_is_member, 2569 CHECK_false); 2570 if (next == NULL) break; 2571 if (next == class2) return true; 2572 outer_this = InstanceKlass::cast(next); 2573 } 2574 2575 // Now do the same for class2. 2576 const InstanceKlass* outer2 = InstanceKlass::cast(class2); 2577 for (;;) { 2578 bool ignore_inner_is_member; 2579 Klass* next = outer2->compute_enclosing_class(&ignore_inner_is_member, 2580 CHECK_false); 2581 if (next == NULL) break; 2582 // Might as well check the new outer against all available values. 2583 if (next == this) return true; 2584 if (next == outer_this) return true; 2585 outer2 = InstanceKlass::cast(next); 2586 } 2587 2588 // If by this point we have not found an equality between the 2589 // two classes, we know they are in separate package members. 2590 return false; 2591 } 2592 2593 bool InstanceKlass::find_inner_classes_attr(int* ooff, int* noff, TRAPS) const { 2594 constantPoolHandle i_cp(THREAD, constants()); 2595 for (InnerClassesIterator iter(this); !iter.done(); iter.next()) { 2596 int ioff = iter.inner_class_info_index(); 2597 if (ioff != 0) { 2598 // Check to see if the name matches the class we're looking for 2599 // before attempting to find the class. 2600 if (i_cp->klass_name_at_matches(this, ioff)) { 2601 Klass* inner_klass = i_cp->klass_at(ioff, CHECK_false); 2602 if (this == inner_klass) { 2603 *ooff = iter.outer_class_info_index(); 2604 *noff = iter.inner_name_index(); 2605 return true; 2606 } 2607 } 2608 } 2609 } 2610 return false; 2611 } 2612 2613 InstanceKlass* InstanceKlass::compute_enclosing_class(bool* inner_is_member, TRAPS) const { 2614 InstanceKlass* outer_klass = NULL; 2615 *inner_is_member = false; 2616 int ooff = 0, noff = 0; 2617 bool has_inner_classes_attr = find_inner_classes_attr(&ooff, &noff, THREAD); 2618 if (has_inner_classes_attr) { 2619 constantPoolHandle i_cp(THREAD, constants()); 2620 if (ooff != 0) { 2621 Klass* ok = i_cp->klass_at(ooff, CHECK_NULL); 2622 outer_klass = InstanceKlass::cast(ok); 2623 *inner_is_member = true; 2624 } 2625 if (NULL == outer_klass) { 2626 // It may be anonymous; try for that. 2627 int encl_method_class_idx = enclosing_method_class_index(); 2628 if (encl_method_class_idx != 0) { 2629 Klass* ok = i_cp->klass_at(encl_method_class_idx, CHECK_NULL); 2630 outer_klass = InstanceKlass::cast(ok); 2631 *inner_is_member = false; 2632 } 2633 } 2634 } 2635 2636 // If no inner class attribute found for this class. 2637 if (NULL == outer_klass) return NULL; 2638 2639 // Throws an exception if outer klass has not declared k as an inner klass 2640 // We need evidence that each klass knows about the other, or else 2641 // the system could allow a spoof of an inner class to gain access rights. 2642 Reflection::check_for_inner_class(outer_klass, this, *inner_is_member, CHECK_NULL); 2643 return outer_klass; 2644 } 2645 2646 jint InstanceKlass::compute_modifier_flags(TRAPS) const { 2647 jint access = access_flags().as_int(); 2648 2649 // But check if it happens to be member class. 2650 InnerClassesIterator iter(this); 2651 for (; !iter.done(); iter.next()) { 2652 int ioff = iter.inner_class_info_index(); 2653 // Inner class attribute can be zero, skip it. 2654 // Strange but true: JVM spec. allows null inner class refs. 2655 if (ioff == 0) continue; 2656 2657 // only look at classes that are already loaded 2658 // since we are looking for the flags for our self. 2659 Symbol* inner_name = constants()->klass_name_at(ioff); 2660 if (name() == inner_name) { 2661 // This is really a member class. 2662 access = iter.inner_access_flags(); 2663 break; 2664 } 2665 } 2666 // Remember to strip ACC_SUPER bit 2667 return (access & (~JVM_ACC_SUPER)) & JVM_ACC_WRITTEN_FLAGS; 2668 } 2669 2670 jint InstanceKlass::jvmti_class_status() const { 2671 jint result = 0; 2672 2673 if (is_linked()) { 2674 result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED; 2675 } 2676 2677 if (is_initialized()) { 2678 assert(is_linked(), "Class status is not consistent"); 2679 result |= JVMTI_CLASS_STATUS_INITIALIZED; 2680 } 2681 if (is_in_error_state()) { 2682 result |= JVMTI_CLASS_STATUS_ERROR; 2683 } 2684 return result; 2685 } 2686 2687 Method* InstanceKlass::method_at_itable(Klass* holder, int index, TRAPS) { 2688 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable(); 2689 int method_table_offset_in_words = ioe->offset()/wordSize; 2690 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words()) 2691 / itableOffsetEntry::size(); 2692 2693 for (int cnt = 0 ; ; cnt ++, ioe ++) { 2694 // If the interface isn't implemented by the receiver class, 2695 // the VM should throw IncompatibleClassChangeError. 2696 if (cnt >= nof_interfaces) { 2697 THROW_NULL(vmSymbols::java_lang_IncompatibleClassChangeError()); 2698 } 2699 2700 Klass* ik = ioe->interface_klass(); 2701 if (ik == holder) break; 2702 } 2703 2704 itableMethodEntry* ime = ioe->first_method_entry(this); 2705 Method* m = ime[index].method(); 2706 if (m == NULL) { 2707 THROW_NULL(vmSymbols::java_lang_AbstractMethodError()); 2708 } 2709 return m; 2710 } 2711 2712 2713 #if INCLUDE_JVMTI 2714 // update default_methods for redefineclasses for methods that are 2715 // not yet in the vtable due to concurrent subclass define and superinterface 2716 // redefinition 2717 // Note: those in the vtable, should have been updated via adjust_method_entries 2718 void InstanceKlass::adjust_default_methods(InstanceKlass* holder, bool* trace_name_printed) { 2719 // search the default_methods for uses of either obsolete or EMCP methods 2720 if (default_methods() != NULL) { 2721 for (int index = 0; index < default_methods()->length(); index ++) { 2722 Method* old_method = default_methods()->at(index); 2723 if (old_method == NULL || old_method->method_holder() != holder || !old_method->is_old()) { 2724 continue; // skip uninteresting entries 2725 } 2726 assert(!old_method->is_deleted(), "default methods may not be deleted"); 2727 2728 Method* new_method = holder->method_with_idnum(old_method->orig_method_idnum()); 2729 2730 assert(new_method != NULL, "method_with_idnum() should not be NULL"); 2731 assert(old_method != new_method, "sanity check"); 2732 2733 default_methods()->at_put(index, new_method); 2734 if (log_is_enabled(Info, redefine, class, update)) { 2735 ResourceMark rm; 2736 if (!(*trace_name_printed)) { 2737 log_info(redefine, class, update) 2738 ("adjust: klassname=%s default methods from name=%s", 2739 external_name(), old_method->method_holder()->external_name()); 2740 *trace_name_printed = true; 2741 } 2742 log_debug(redefine, class, update, vtables) 2743 ("default method update: %s(%s) ", 2744 new_method->name()->as_C_string(), new_method->signature()->as_C_string()); 2745 } 2746 } 2747 } 2748 } 2749 #endif // INCLUDE_JVMTI 2750 2751 // On-stack replacement stuff 2752 void InstanceKlass::add_osr_nmethod(nmethod* n) { 2753 // only one compilation can be active 2754 { 2755 // This is a short non-blocking critical region, so the no safepoint check is ok. 2756 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag); 2757 assert(n->is_osr_method(), "wrong kind of nmethod"); 2758 n->set_osr_link(osr_nmethods_head()); 2759 set_osr_nmethods_head(n); 2760 // Raise the highest osr level if necessary 2761 if (TieredCompilation) { 2762 Method* m = n->method(); 2763 m->set_highest_osr_comp_level(MAX2(m->highest_osr_comp_level(), n->comp_level())); 2764 } 2765 } 2766 2767 // Get rid of the osr methods for the same bci that have lower levels. 2768 if (TieredCompilation) { 2769 for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) { 2770 nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true); 2771 if (inv != NULL && inv->is_in_use()) { 2772 inv->make_not_entrant(); 2773 } 2774 } 2775 } 2776 } 2777 2778 // Remove osr nmethod from the list. Return true if found and removed. 2779 bool InstanceKlass::remove_osr_nmethod(nmethod* n) { 2780 // This is a short non-blocking critical region, so the no safepoint check is ok. 2781 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag); 2782 assert(n->is_osr_method(), "wrong kind of nmethod"); 2783 nmethod* last = NULL; 2784 nmethod* cur = osr_nmethods_head(); 2785 int max_level = CompLevel_none; // Find the max comp level excluding n 2786 Method* m = n->method(); 2787 // Search for match 2788 bool found = false; 2789 while(cur != NULL && cur != n) { 2790 if (TieredCompilation && m == cur->method()) { 2791 // Find max level before n 2792 max_level = MAX2(max_level, cur->comp_level()); 2793 } 2794 last = cur; 2795 cur = cur->osr_link(); 2796 } 2797 nmethod* next = NULL; 2798 if (cur == n) { 2799 found = true; 2800 next = cur->osr_link(); 2801 if (last == NULL) { 2802 // Remove first element 2803 set_osr_nmethods_head(next); 2804 } else { 2805 last->set_osr_link(next); 2806 } 2807 } 2808 n->set_osr_link(NULL); 2809 if (TieredCompilation) { 2810 cur = next; 2811 while (cur != NULL) { 2812 // Find max level after n 2813 if (m == cur->method()) { 2814 max_level = MAX2(max_level, cur->comp_level()); 2815 } 2816 cur = cur->osr_link(); 2817 } 2818 m->set_highest_osr_comp_level(max_level); 2819 } 2820 return found; 2821 } 2822 2823 int InstanceKlass::mark_osr_nmethods(const Method* m) { 2824 // This is a short non-blocking critical region, so the no safepoint check is ok. 2825 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag); 2826 nmethod* osr = osr_nmethods_head(); 2827 int found = 0; 2828 while (osr != NULL) { 2829 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain"); 2830 if (osr->method() == m) { 2831 osr->mark_for_deoptimization(); 2832 found++; 2833 } 2834 osr = osr->osr_link(); 2835 } 2836 return found; 2837 } 2838 2839 nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const { 2840 // This is a short non-blocking critical region, so the no safepoint check is ok. 2841 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag); 2842 nmethod* osr = osr_nmethods_head(); 2843 nmethod* best = NULL; 2844 while (osr != NULL) { 2845 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain"); 2846 // There can be a time when a c1 osr method exists but we are waiting 2847 // for a c2 version. When c2 completes its osr nmethod we will trash 2848 // the c1 version and only be able to find the c2 version. However 2849 // while we overflow in the c1 code at back branches we don't want to 2850 // try and switch to the same code as we are already running 2851 2852 if (osr->method() == m && 2853 (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) { 2854 if (match_level) { 2855 if (osr->comp_level() == comp_level) { 2856 // Found a match - return it. 2857 return osr; 2858 } 2859 } else { 2860 if (best == NULL || (osr->comp_level() > best->comp_level())) { 2861 if (osr->comp_level() == CompLevel_highest_tier) { 2862 // Found the best possible - return it. 2863 return osr; 2864 } 2865 best = osr; 2866 } 2867 } 2868 } 2869 osr = osr->osr_link(); 2870 } 2871 if (best != NULL && best->comp_level() >= comp_level && match_level == false) { 2872 return best; 2873 } 2874 return NULL; 2875 } 2876 2877 oop InstanceKlass::add_member_name(Handle mem_name, bool intern) { 2878 jweak mem_name_wref = JNIHandles::make_weak_global(mem_name); 2879 MutexLocker ml(MemberNameTable_lock); 2880 DEBUG_ONLY(NoSafepointVerifier nsv); 2881 2882 // Check if method has been redefined while taking out MemberNameTable_lock, if so 2883 // return false. We cannot cache obsolete methods. They will crash when the function 2884 // is called! 2885 Method* method = (Method*)java_lang_invoke_MemberName::vmtarget(mem_name()); 2886 if (method->is_obsolete()) { 2887 return NULL; 2888 } else if (method->is_old()) { 2889 // Replace method with redefined version 2890 java_lang_invoke_MemberName::set_vmtarget(mem_name(), method_with_idnum(method->method_idnum())); 2891 } 2892 2893 if (_member_names == NULL) { 2894 _member_names = new (ResourceObj::C_HEAP, mtClass) MemberNameTable(idnum_allocated_count()); 2895 } 2896 if (intern) { 2897 return _member_names->find_or_add_member_name(mem_name_wref); 2898 } else { 2899 return _member_names->add_member_name(mem_name_wref); 2900 } 2901 } 2902 2903 // ----------------------------------------------------------------------------------------------------- 2904 // Printing 2905 2906 #ifndef PRODUCT 2907 2908 #define BULLET " - " 2909 2910 static const char* state_names[] = { 2911 "allocated", "loaded", "linked", "being_initialized", "fully_initialized", "initialization_error" 2912 }; 2913 2914 static void print_vtable(address self, intptr_t* start, int len, outputStream* st) { 2915 ResourceMark rm; 2916 int* forward_refs = NEW_RESOURCE_ARRAY(int, len); 2917 for (int i = 0; i < len; i++) forward_refs[i] = 0; 2918 for (int i = 0; i < len; i++) { 2919 intptr_t e = start[i]; 2920 st->print("%d : " INTPTR_FORMAT, i, e); 2921 if (forward_refs[i] != 0) { 2922 int from = forward_refs[i]; 2923 int off = (int) start[from]; 2924 st->print(" (offset %d <= [%d])", off, from); 2925 } 2926 if (e != 0 && ((Metadata*)e)->is_metaspace_object()) { 2927 st->print(" "); 2928 ((Metadata*)e)->print_value_on(st); 2929 } else if (self != NULL && e > 0 && e < 0x10000) { 2930 address location = self + e; 2931 int index = (int)((intptr_t*)location - start); 2932 st->print(" (offset %d => [%d])", (int)e, index); 2933 if (index >= 0 && index < len) 2934 forward_refs[index] = i; 2935 } 2936 st->cr(); 2937 } 2938 } 2939 2940 static void print_vtable(vtableEntry* start, int len, outputStream* st) { 2941 return print_vtable(NULL, reinterpret_cast<intptr_t*>(start), len, st); 2942 } 2943 2944 template<typename T> 2945 static void print_array_on(outputStream* st, Array<T>* array) { 2946 if (array == NULL) { st->print_cr("NULL"); return; } 2947 array->print_value_on(st); st->cr(); 2948 if (Verbose || WizardMode) { 2949 for (int i = 0; i < array->length(); i++) { 2950 st->print("%d : ", i); array->at(i)->print_value_on(st); st->cr(); 2951 } 2952 } 2953 } 2954 2955 static void print_array_on(outputStream* st, Array<int>* array) { 2956 if (array == NULL) { st->print_cr("NULL"); return; } 2957 array->print_value_on(st); st->cr(); 2958 if (Verbose || WizardMode) { 2959 for (int i = 0; i < array->length(); i++) { 2960 st->print("%d : %d", i, array->at(i)); st->cr(); 2961 } 2962 } 2963 } 2964 2965 void InstanceKlass::print_on(outputStream* st) const { 2966 assert(is_klass(), "must be klass"); 2967 Klass::print_on(st); 2968 2969 st->print(BULLET"instance size: %d", size_helper()); st->cr(); 2970 st->print(BULLET"klass size: %d", size()); st->cr(); 2971 st->print(BULLET"access: "); access_flags().print_on(st); st->cr(); 2972 st->print(BULLET"misc flags: 0x%x", _misc_flags); st->cr(); 2973 st->print(BULLET"state: "); st->print_cr("%s", state_names[_init_state]); 2974 st->print(BULLET"name: "); name()->print_value_on(st); st->cr(); 2975 st->print(BULLET"super: "); super()->print_value_on_maybe_null(st); st->cr(); 2976 st->print(BULLET"sub: "); 2977 Klass* sub = subklass(); 2978 int n; 2979 for (n = 0; sub != NULL; n++, sub = sub->next_sibling()) { 2980 if (n < MaxSubklassPrintSize) { 2981 sub->print_value_on(st); 2982 st->print(" "); 2983 } 2984 } 2985 if (n >= MaxSubklassPrintSize) st->print("(" INTX_FORMAT " more klasses...)", n - MaxSubklassPrintSize); 2986 st->cr(); 2987 2988 if (is_interface()) { 2989 st->print_cr(BULLET"nof implementors: %d", nof_implementors()); 2990 if (nof_implementors() == 1) { 2991 st->print_cr(BULLET"implementor: "); 2992 st->print(" "); 2993 implementor()->print_value_on(st); 2994 st->cr(); 2995 } 2996 } 2997 2998 st->print(BULLET"arrays: "); array_klasses()->print_value_on_maybe_null(st); st->cr(); 2999 st->print(BULLET"methods: "); print_array_on(st, methods()); 3000 st->print(BULLET"method ordering: "); print_array_on(st, method_ordering()); 3001 st->print(BULLET"default_methods: "); print_array_on(st, default_methods()); 3002 if (default_vtable_indices() != NULL) { 3003 st->print(BULLET"default vtable indices: "); print_array_on(st, default_vtable_indices()); 3004 } 3005 st->print(BULLET"local interfaces: "); print_array_on(st, local_interfaces()); 3006 st->print(BULLET"trans. interfaces: "); print_array_on(st, transitive_interfaces()); 3007 st->print(BULLET"constants: "); constants()->print_value_on(st); st->cr(); 3008 if (class_loader_data() != NULL) { 3009 st->print(BULLET"class loader data: "); 3010 class_loader_data()->print_value_on(st); 3011 st->cr(); 3012 } 3013 st->print(BULLET"host class: "); host_klass()->print_value_on_maybe_null(st); st->cr(); 3014 if (source_file_name() != NULL) { 3015 st->print(BULLET"source file: "); 3016 source_file_name()->print_value_on(st); 3017 st->cr(); 3018 } 3019 if (source_debug_extension() != NULL) { 3020 st->print(BULLET"source debug extension: "); 3021 st->print("%s", source_debug_extension()); 3022 st->cr(); 3023 } 3024 st->print(BULLET"class annotations: "); class_annotations()->print_value_on(st); st->cr(); 3025 st->print(BULLET"class type annotations: "); class_type_annotations()->print_value_on(st); st->cr(); 3026 st->print(BULLET"field annotations: "); fields_annotations()->print_value_on(st); st->cr(); 3027 st->print(BULLET"field type annotations: "); fields_type_annotations()->print_value_on(st); st->cr(); 3028 { 3029 bool have_pv = false; 3030 // previous versions are linked together through the InstanceKlass 3031 for (InstanceKlass* pv_node = previous_versions(); 3032 pv_node != NULL; 3033 pv_node = pv_node->previous_versions()) { 3034 if (!have_pv) 3035 st->print(BULLET"previous version: "); 3036 have_pv = true; 3037 pv_node->constants()->print_value_on(st); 3038 } 3039 if (have_pv) st->cr(); 3040 } 3041 3042 if (generic_signature() != NULL) { 3043 st->print(BULLET"generic signature: "); 3044 generic_signature()->print_value_on(st); 3045 st->cr(); 3046 } 3047 st->print(BULLET"inner classes: "); inner_classes()->print_value_on(st); st->cr(); 3048 st->print(BULLET"java mirror: "); java_mirror()->print_value_on(st); st->cr(); 3049 st->print(BULLET"vtable length %d (start addr: " INTPTR_FORMAT ")", vtable_length(), p2i(start_of_vtable())); st->cr(); 3050 if (vtable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_vtable(), vtable_length(), st); 3051 st->print(BULLET"itable length %d (start addr: " INTPTR_FORMAT ")", itable_length(), p2i(start_of_itable())); st->cr(); 3052 if (itable_length() > 0 && (Verbose || WizardMode)) print_vtable(NULL, start_of_itable(), itable_length(), st); 3053 st->print_cr(BULLET"---- static fields (%d words):", static_field_size()); 3054 FieldPrinter print_static_field(st); 3055 ((InstanceKlass*)this)->do_local_static_fields(&print_static_field); 3056 st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size()); 3057 FieldPrinter print_nonstatic_field(st); 3058 InstanceKlass* ik = const_cast<InstanceKlass*>(this); 3059 ik->do_nonstatic_fields(&print_nonstatic_field); 3060 3061 st->print(BULLET"non-static oop maps: "); 3062 OopMapBlock* map = start_of_nonstatic_oop_maps(); 3063 OopMapBlock* end_map = map + nonstatic_oop_map_count(); 3064 while (map < end_map) { 3065 st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1)); 3066 map++; 3067 } 3068 st->cr(); 3069 } 3070 3071 #endif //PRODUCT 3072 3073 void InstanceKlass::print_value_on(outputStream* st) const { 3074 assert(is_klass(), "must be klass"); 3075 if (Verbose || WizardMode) access_flags().print_on(st); 3076 name()->print_value_on(st); 3077 } 3078 3079 #ifndef PRODUCT 3080 3081 void FieldPrinter::do_field(fieldDescriptor* fd) { 3082 _st->print(BULLET); 3083 if (_obj == NULL) { 3084 fd->print_on(_st); 3085 _st->cr(); 3086 } else { 3087 fd->print_on_for(_st, _obj); 3088 _st->cr(); 3089 } 3090 } 3091 3092 3093 void InstanceKlass::oop_print_on(oop obj, outputStream* st) { 3094 Klass::oop_print_on(obj, st); 3095 3096 if (this == SystemDictionary::String_klass()) { 3097 typeArrayOop value = java_lang_String::value(obj); 3098 juint length = java_lang_String::length(obj); 3099 if (value != NULL && 3100 value->is_typeArray() && 3101 length <= (juint) value->length()) { 3102 st->print(BULLET"string: "); 3103 java_lang_String::print(obj, st); 3104 st->cr(); 3105 if (!WizardMode) return; // that is enough 3106 } 3107 } 3108 3109 st->print_cr(BULLET"---- fields (total size %d words):", oop_size(obj)); 3110 FieldPrinter print_field(st, obj); 3111 do_nonstatic_fields(&print_field); 3112 3113 if (this == SystemDictionary::Class_klass()) { 3114 st->print(BULLET"signature: "); 3115 java_lang_Class::print_signature(obj, st); 3116 st->cr(); 3117 Klass* mirrored_klass = java_lang_Class::as_Klass(obj); 3118 st->print(BULLET"fake entry for mirror: "); 3119 mirrored_klass->print_value_on_maybe_null(st); 3120 st->cr(); 3121 Klass* array_klass = java_lang_Class::array_klass(obj); 3122 st->print(BULLET"fake entry for array: "); 3123 array_klass->print_value_on_maybe_null(st); 3124 st->cr(); 3125 st->print_cr(BULLET"fake entry for oop_size: %d", java_lang_Class::oop_size(obj)); 3126 st->print_cr(BULLET"fake entry for static_oop_field_count: %d", java_lang_Class::static_oop_field_count(obj)); 3127 Klass* real_klass = java_lang_Class::as_Klass(obj); 3128 if (real_klass != NULL && real_klass->is_instance_klass()) { 3129 InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field); 3130 } 3131 } else if (this == SystemDictionary::MethodType_klass()) { 3132 st->print(BULLET"signature: "); 3133 java_lang_invoke_MethodType::print_signature(obj, st); 3134 st->cr(); 3135 } 3136 } 3137 3138 #endif //PRODUCT 3139 3140 void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) { 3141 st->print("a "); 3142 name()->print_value_on(st); 3143 obj->print_address_on(st); 3144 if (this == SystemDictionary::String_klass() 3145 && java_lang_String::value(obj) != NULL) { 3146 ResourceMark rm; 3147 int len = java_lang_String::length(obj); 3148 int plen = (len < 24 ? len : 12); 3149 char* str = java_lang_String::as_utf8_string(obj, 0, plen); 3150 st->print(" = \"%s\"", str); 3151 if (len > plen) 3152 st->print("...[%d]", len); 3153 } else if (this == SystemDictionary::Class_klass()) { 3154 Klass* k = java_lang_Class::as_Klass(obj); 3155 st->print(" = "); 3156 if (k != NULL) { 3157 k->print_value_on(st); 3158 } else { 3159 const char* tname = type2name(java_lang_Class::primitive_type(obj)); 3160 st->print("%s", tname ? tname : "type?"); 3161 } 3162 } else if (this == SystemDictionary::MethodType_klass()) { 3163 st->print(" = "); 3164 java_lang_invoke_MethodType::print_signature(obj, st); 3165 } else if (java_lang_boxing_object::is_instance(obj)) { 3166 st->print(" = "); 3167 java_lang_boxing_object::print(obj, st); 3168 } else if (this == SystemDictionary::LambdaForm_klass()) { 3169 oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj); 3170 if (vmentry != NULL) { 3171 st->print(" => "); 3172 vmentry->print_value_on(st); 3173 } 3174 } else if (this == SystemDictionary::MemberName_klass()) { 3175 Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj); 3176 if (vmtarget != NULL) { 3177 st->print(" = "); 3178 vmtarget->print_value_on(st); 3179 } else { 3180 java_lang_invoke_MemberName::clazz(obj)->print_value_on(st); 3181 st->print("."); 3182 java_lang_invoke_MemberName::name(obj)->print_value_on(st); 3183 } 3184 } 3185 } 3186 3187 const char* InstanceKlass::internal_name() const { 3188 return external_name(); 3189 } 3190 3191 void InstanceKlass::print_class_load_logging(ClassLoaderData* loader_data, 3192 const char* module_name, 3193 const ClassFileStream* cfs) const { 3194 if (!log_is_enabled(Info, class, load)) { 3195 return; 3196 } 3197 3198 ResourceMark rm; 3199 LogMessage(class, load) msg; 3200 stringStream info_stream; 3201 3202 // Name and class hierarchy info 3203 info_stream.print("%s", external_name()); 3204 3205 // Source 3206 if (cfs != NULL) { 3207 if (cfs->source() != NULL) { 3208 if (module_name != NULL) { 3209 if (ClassLoader::is_jrt(cfs->source())) { 3210 info_stream.print(" source: jrt:/%s", module_name); 3211 } else { 3212 info_stream.print(" source: %s", cfs->source()); 3213 } 3214 } else { 3215 info_stream.print(" source: %s", cfs->source()); 3216 } 3217 } else if (loader_data == ClassLoaderData::the_null_class_loader_data()) { 3218 Thread* THREAD = Thread::current(); 3219 Klass* caller = 3220 THREAD->is_Java_thread() 3221 ? ((JavaThread*)THREAD)->security_get_caller_class(1) 3222 : NULL; 3223 // caller can be NULL, for example, during a JVMTI VM_Init hook 3224 if (caller != NULL) { 3225 info_stream.print(" source: instance of %s", caller->external_name()); 3226 } else { 3227 // source is unknown 3228 } 3229 } else { 3230 oop class_loader = loader_data->class_loader(); 3231 info_stream.print(" source: %s", class_loader->klass()->external_name()); 3232 } 3233 } else { 3234 info_stream.print(" source: shared objects file"); 3235 } 3236 3237 msg.info("%s", info_stream.as_string()); 3238 3239 if (log_is_enabled(Debug, class, load)) { 3240 stringStream debug_stream; 3241 3242 // Class hierarchy info 3243 debug_stream.print(" klass: " INTPTR_FORMAT " super: " INTPTR_FORMAT, 3244 p2i(this), p2i(superklass())); 3245 3246 // Interfaces 3247 if (local_interfaces() != NULL && local_interfaces()->length() > 0) { 3248 debug_stream.print(" interfaces:"); 3249 int length = local_interfaces()->length(); 3250 for (int i = 0; i < length; i++) { 3251 debug_stream.print(" " INTPTR_FORMAT, 3252 p2i(InstanceKlass::cast(local_interfaces()->at(i)))); 3253 } 3254 } 3255 3256 // Class loader 3257 debug_stream.print(" loader: ["); 3258 loader_data->print_value_on(&debug_stream); 3259 debug_stream.print("]"); 3260 3261 // Classfile checksum 3262 if (cfs) { 3263 debug_stream.print(" bytes: %d checksum: %08x", 3264 cfs->length(), 3265 ClassLoader::crc32(0, (const char*)cfs->buffer(), 3266 cfs->length())); 3267 } 3268 3269 msg.debug("%s", debug_stream.as_string()); 3270 } 3271 } 3272 3273 #if INCLUDE_SERVICES 3274 // Size Statistics 3275 void InstanceKlass::collect_statistics(KlassSizeStats *sz) const { 3276 Klass::collect_statistics(sz); 3277 3278 sz->_inst_size = wordSize * size_helper(); 3279 sz->_vtab_bytes = wordSize * vtable_length(); 3280 sz->_itab_bytes = wordSize * itable_length(); 3281 sz->_nonstatic_oopmap_bytes = wordSize * nonstatic_oop_map_size(); 3282 3283 int n = 0; 3284 n += (sz->_methods_array_bytes = sz->count_array(methods())); 3285 n += (sz->_method_ordering_bytes = sz->count_array(method_ordering())); 3286 n += (sz->_local_interfaces_bytes = sz->count_array(local_interfaces())); 3287 n += (sz->_transitive_interfaces_bytes = sz->count_array(transitive_interfaces())); 3288 n += (sz->_fields_bytes = sz->count_array(fields())); 3289 n += (sz->_inner_classes_bytes = sz->count_array(inner_classes())); 3290 sz->_ro_bytes += n; 3291 3292 const ConstantPool* cp = constants(); 3293 if (cp) { 3294 cp->collect_statistics(sz); 3295 } 3296 3297 const Annotations* anno = annotations(); 3298 if (anno) { 3299 anno->collect_statistics(sz); 3300 } 3301 3302 const Array<Method*>* methods_array = methods(); 3303 if (methods()) { 3304 for (int i = 0; i < methods_array->length(); i++) { 3305 Method* method = methods_array->at(i); 3306 if (method) { 3307 sz->_method_count ++; 3308 method->collect_statistics(sz); 3309 } 3310 } 3311 } 3312 } 3313 #endif // INCLUDE_SERVICES 3314 3315 // Verification 3316 3317 class VerifyFieldClosure: public OopClosure { 3318 protected: 3319 template <class T> void do_oop_work(T* p) { 3320 oop obj = oopDesc::load_decode_heap_oop(p); 3321 if (!obj->is_oop_or_null()) { 3322 tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p2i(p), p2i(obj)); 3323 Universe::print_on(tty); 3324 guarantee(false, "boom"); 3325 } 3326 } 3327 public: 3328 virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); } 3329 virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); } 3330 }; 3331 3332 void InstanceKlass::verify_on(outputStream* st) { 3333 #ifndef PRODUCT 3334 // Avoid redundant verifies, this really should be in product. 3335 if (_verify_count == Universe::verify_count()) return; 3336 _verify_count = Universe::verify_count(); 3337 #endif 3338 3339 // Verify Klass 3340 Klass::verify_on(st); 3341 3342 // Verify that klass is present in ClassLoaderData 3343 guarantee(class_loader_data()->contains_klass(this), 3344 "this class isn't found in class loader data"); 3345 3346 // Verify vtables 3347 if (is_linked()) { 3348 // $$$ This used to be done only for m/s collections. Doing it 3349 // always seemed a valid generalization. (DLD -- 6/00) 3350 vtable().verify(st); 3351 } 3352 3353 // Verify first subklass 3354 if (subklass() != NULL) { 3355 guarantee(subklass()->is_klass(), "should be klass"); 3356 } 3357 3358 // Verify siblings 3359 Klass* super = this->super(); 3360 Klass* sib = next_sibling(); 3361 if (sib != NULL) { 3362 if (sib == this) { 3363 fatal("subclass points to itself " PTR_FORMAT, p2i(sib)); 3364 } 3365 3366 guarantee(sib->is_klass(), "should be klass"); 3367 guarantee(sib->super() == super, "siblings should have same superklass"); 3368 } 3369 3370 // Verify implementor fields 3371 Klass* im = implementor(); 3372 if (im != NULL) { 3373 guarantee(is_interface(), "only interfaces should have implementor set"); 3374 guarantee(im->is_klass(), "should be klass"); 3375 guarantee(!im->is_interface() || im == this, 3376 "implementors cannot be interfaces"); 3377 } 3378 3379 // Verify local interfaces 3380 if (local_interfaces()) { 3381 Array<Klass*>* local_interfaces = this->local_interfaces(); 3382 for (int j = 0; j < local_interfaces->length(); j++) { 3383 Klass* e = local_interfaces->at(j); 3384 guarantee(e->is_klass() && e->is_interface(), "invalid local interface"); 3385 } 3386 } 3387 3388 // Verify transitive interfaces 3389 if (transitive_interfaces() != NULL) { 3390 Array<Klass*>* transitive_interfaces = this->transitive_interfaces(); 3391 for (int j = 0; j < transitive_interfaces->length(); j++) { 3392 Klass* e = transitive_interfaces->at(j); 3393 guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface"); 3394 } 3395 } 3396 3397 // Verify methods 3398 if (methods() != NULL) { 3399 Array<Method*>* methods = this->methods(); 3400 for (int j = 0; j < methods->length(); j++) { 3401 guarantee(methods->at(j)->is_method(), "non-method in methods array"); 3402 } 3403 for (int j = 0; j < methods->length() - 1; j++) { 3404 Method* m1 = methods->at(j); 3405 Method* m2 = methods->at(j + 1); 3406 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly"); 3407 } 3408 } 3409 3410 // Verify method ordering 3411 if (method_ordering() != NULL) { 3412 Array<int>* method_ordering = this->method_ordering(); 3413 int length = method_ordering->length(); 3414 if (JvmtiExport::can_maintain_original_method_order() || 3415 ((UseSharedSpaces || DumpSharedSpaces) && length != 0)) { 3416 guarantee(length == methods()->length(), "invalid method ordering length"); 3417 jlong sum = 0; 3418 for (int j = 0; j < length; j++) { 3419 int original_index = method_ordering->at(j); 3420 guarantee(original_index >= 0, "invalid method ordering index"); 3421 guarantee(original_index < length, "invalid method ordering index"); 3422 sum += original_index; 3423 } 3424 // Verify sum of indices 0,1,...,length-1 3425 guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum"); 3426 } else { 3427 guarantee(length == 0, "invalid method ordering length"); 3428 } 3429 } 3430 3431 // Verify default methods 3432 if (default_methods() != NULL) { 3433 Array<Method*>* methods = this->default_methods(); 3434 for (int j = 0; j < methods->length(); j++) { 3435 guarantee(methods->at(j)->is_method(), "non-method in methods array"); 3436 } 3437 for (int j = 0; j < methods->length() - 1; j++) { 3438 Method* m1 = methods->at(j); 3439 Method* m2 = methods->at(j + 1); 3440 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly"); 3441 } 3442 } 3443 3444 // Verify JNI static field identifiers 3445 if (jni_ids() != NULL) { 3446 jni_ids()->verify(this); 3447 } 3448 3449 // Verify other fields 3450 if (array_klasses() != NULL) { 3451 guarantee(array_klasses()->is_klass(), "should be klass"); 3452 } 3453 if (constants() != NULL) { 3454 guarantee(constants()->is_constantPool(), "should be constant pool"); 3455 } 3456 const Klass* host = host_klass(); 3457 if (host != NULL) { 3458 guarantee(host->is_klass(), "should be klass"); 3459 } 3460 } 3461 3462 void InstanceKlass::oop_verify_on(oop obj, outputStream* st) { 3463 Klass::oop_verify_on(obj, st); 3464 VerifyFieldClosure blk; 3465 obj->oop_iterate_no_header(&blk); 3466 } 3467 3468 3469 // JNIid class for jfieldIDs only 3470 // Note to reviewers: 3471 // These JNI functions are just moved over to column 1 and not changed 3472 // in the compressed oops workspace. 3473 JNIid::JNIid(Klass* holder, int offset, JNIid* next) { 3474 _holder = holder; 3475 _offset = offset; 3476 _next = next; 3477 debug_only(_is_static_field_id = false;) 3478 } 3479 3480 3481 JNIid* JNIid::find(int offset) { 3482 JNIid* current = this; 3483 while (current != NULL) { 3484 if (current->offset() == offset) return current; 3485 current = current->next(); 3486 } 3487 return NULL; 3488 } 3489 3490 void JNIid::deallocate(JNIid* current) { 3491 while (current != NULL) { 3492 JNIid* next = current->next(); 3493 delete current; 3494 current = next; 3495 } 3496 } 3497 3498 3499 void JNIid::verify(Klass* holder) { 3500 int first_field_offset = InstanceMirrorKlass::offset_of_static_fields(); 3501 int end_field_offset; 3502 end_field_offset = first_field_offset + (InstanceKlass::cast(holder)->static_field_size() * wordSize); 3503 3504 JNIid* current = this; 3505 while (current != NULL) { 3506 guarantee(current->holder() == holder, "Invalid klass in JNIid"); 3507 #ifdef ASSERT 3508 int o = current->offset(); 3509 if (current->is_static_field_id()) { 3510 guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid"); 3511 } 3512 #endif 3513 current = current->next(); 3514 } 3515 } 3516 3517 3518 #ifdef ASSERT 3519 void InstanceKlass::set_init_state(ClassState state) { 3520 bool good_state = is_shared() ? (_init_state <= state) 3521 : (_init_state < state); 3522 assert(good_state || state == allocated, "illegal state transition"); 3523 _init_state = (u1)state; 3524 } 3525 #endif 3526 3527 #if INCLUDE_JVMTI 3528 3529 // RedefineClasses() support for previous versions 3530 3531 // Globally, there is at least one previous version of a class to walk 3532 // during class unloading, which is saved because old methods in the class 3533 // are still running. Otherwise the previous version list is cleaned up. 3534 bool InstanceKlass::_has_previous_versions = false; 3535 3536 // Returns true if there are previous versions of a class for class 3537 // unloading only. Also resets the flag to false. purge_previous_version 3538 // will set the flag to true if there are any left, i.e., if there's any 3539 // work to do for next time. This is to avoid the expensive code cache 3540 // walk in CLDG::do_unloading(). 3541 bool InstanceKlass::has_previous_versions_and_reset() { 3542 bool ret = _has_previous_versions; 3543 log_trace(redefine, class, iklass, purge)("Class unloading: has_previous_versions = %s", 3544 ret ? "true" : "false"); 3545 _has_previous_versions = false; 3546 return ret; 3547 } 3548 3549 // Purge previous versions before adding new previous versions of the class and 3550 // during class unloading. 3551 void InstanceKlass::purge_previous_version_list() { 3552 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint"); 3553 assert(has_been_redefined(), "Should only be called for main class"); 3554 3555 // Quick exit. 3556 if (previous_versions() == NULL) { 3557 return; 3558 } 3559 3560 // This klass has previous versions so see what we can cleanup 3561 // while it is safe to do so. 3562 3563 int deleted_count = 0; // leave debugging breadcrumbs 3564 int live_count = 0; 3565 ClassLoaderData* loader_data = class_loader_data(); 3566 assert(loader_data != NULL, "should never be null"); 3567 3568 ResourceMark rm; 3569 log_trace(redefine, class, iklass, purge)("%s: previous versions", external_name()); 3570 3571 // previous versions are linked together through the InstanceKlass 3572 InstanceKlass* pv_node = previous_versions(); 3573 InstanceKlass* last = this; 3574 int version = 0; 3575 3576 // check the previous versions list 3577 for (; pv_node != NULL; ) { 3578 3579 ConstantPool* pvcp = pv_node->constants(); 3580 assert(pvcp != NULL, "cp ref was unexpectedly cleared"); 3581 3582 if (!pvcp->on_stack()) { 3583 // If the constant pool isn't on stack, none of the methods 3584 // are executing. Unlink this previous_version. 3585 // The previous version InstanceKlass is on the ClassLoaderData deallocate list 3586 // so will be deallocated during the next phase of class unloading. 3587 log_trace(redefine, class, iklass, purge) 3588 ("previous version " INTPTR_FORMAT " is dead.", p2i(pv_node)); 3589 // For debugging purposes. 3590 pv_node->set_is_scratch_class(); 3591 // Unlink from previous version list. 3592 assert(pv_node->class_loader_data() == loader_data, "wrong loader_data"); 3593 InstanceKlass* next = pv_node->previous_versions(); 3594 pv_node->link_previous_versions(NULL); // point next to NULL 3595 last->link_previous_versions(next); 3596 // Add to the deallocate list after unlinking 3597 loader_data->add_to_deallocate_list(pv_node); 3598 pv_node = next; 3599 deleted_count++; 3600 version++; 3601 continue; 3602 } else { 3603 log_trace(redefine, class, iklass, purge)("previous version " INTPTR_FORMAT " is alive", p2i(pv_node)); 3604 assert(pvcp->pool_holder() != NULL, "Constant pool with no holder"); 3605 guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack"); 3606 live_count++; 3607 // found a previous version for next time we do class unloading 3608 _has_previous_versions = true; 3609 } 3610 3611 // At least one method is live in this previous version. 3612 // Reset dead EMCP methods not to get breakpoints. 3613 // All methods are deallocated when all of the methods for this class are no 3614 // longer running. 3615 Array<Method*>* method_refs = pv_node->methods(); 3616 if (method_refs != NULL) { 3617 log_trace(redefine, class, iklass, purge)("previous methods length=%d", method_refs->length()); 3618 for (int j = 0; j < method_refs->length(); j++) { 3619 Method* method = method_refs->at(j); 3620 3621 if (!method->on_stack()) { 3622 // no breakpoints for non-running methods 3623 if (method->is_running_emcp()) { 3624 method->set_running_emcp(false); 3625 } 3626 } else { 3627 assert (method->is_obsolete() || method->is_running_emcp(), 3628 "emcp method cannot run after emcp bit is cleared"); 3629 log_trace(redefine, class, iklass, purge) 3630 ("purge: %s(%s): prev method @%d in version @%d is alive", 3631 method->name()->as_C_string(), method->signature()->as_C_string(), j, version); 3632 } 3633 } 3634 } 3635 // next previous version 3636 last = pv_node; 3637 pv_node = pv_node->previous_versions(); 3638 version++; 3639 } 3640 log_trace(redefine, class, iklass, purge) 3641 ("previous version stats: live=%d, deleted=%d", live_count, deleted_count); 3642 } 3643 3644 void InstanceKlass::mark_newly_obsolete_methods(Array<Method*>* old_methods, 3645 int emcp_method_count) { 3646 int obsolete_method_count = old_methods->length() - emcp_method_count; 3647 3648 if (emcp_method_count != 0 && obsolete_method_count != 0 && 3649 _previous_versions != NULL) { 3650 // We have a mix of obsolete and EMCP methods so we have to 3651 // clear out any matching EMCP method entries the hard way. 3652 int local_count = 0; 3653 for (int i = 0; i < old_methods->length(); i++) { 3654 Method* old_method = old_methods->at(i); 3655 if (old_method->is_obsolete()) { 3656 // only obsolete methods are interesting 3657 Symbol* m_name = old_method->name(); 3658 Symbol* m_signature = old_method->signature(); 3659 3660 // previous versions are linked together through the InstanceKlass 3661 int j = 0; 3662 for (InstanceKlass* prev_version = _previous_versions; 3663 prev_version != NULL; 3664 prev_version = prev_version->previous_versions(), j++) { 3665 3666 Array<Method*>* method_refs = prev_version->methods(); 3667 for (int k = 0; k < method_refs->length(); k++) { 3668 Method* method = method_refs->at(k); 3669 3670 if (!method->is_obsolete() && 3671 method->name() == m_name && 3672 method->signature() == m_signature) { 3673 // The current RedefineClasses() call has made all EMCP 3674 // versions of this method obsolete so mark it as obsolete 3675 log_trace(redefine, class, iklass, add) 3676 ("%s(%s): flush obsolete method @%d in version @%d", 3677 m_name->as_C_string(), m_signature->as_C_string(), k, j); 3678 3679 method->set_is_obsolete(); 3680 break; 3681 } 3682 } 3683 3684 // The previous loop may not find a matching EMCP method, but 3685 // that doesn't mean that we can optimize and not go any 3686 // further back in the PreviousVersion generations. The EMCP 3687 // method for this generation could have already been made obsolete, 3688 // but there still may be an older EMCP method that has not 3689 // been made obsolete. 3690 } 3691 3692 if (++local_count >= obsolete_method_count) { 3693 // no more obsolete methods so bail out now 3694 break; 3695 } 3696 } 3697 } 3698 } 3699 } 3700 3701 // Save the scratch_class as the previous version if any of the methods are running. 3702 // The previous_versions are used to set breakpoints in EMCP methods and they are 3703 // also used to clean MethodData links to redefined methods that are no longer running. 3704 void InstanceKlass::add_previous_version(InstanceKlass* scratch_class, 3705 int emcp_method_count) { 3706 assert(Thread::current()->is_VM_thread(), 3707 "only VMThread can add previous versions"); 3708 3709 ResourceMark rm; 3710 log_trace(redefine, class, iklass, add) 3711 ("adding previous version ref for %s, EMCP_cnt=%d", scratch_class->external_name(), emcp_method_count); 3712 3713 // Clean out old previous versions for this class 3714 purge_previous_version_list(); 3715 3716 // Mark newly obsolete methods in remaining previous versions. An EMCP method from 3717 // a previous redefinition may be made obsolete by this redefinition. 3718 Array<Method*>* old_methods = scratch_class->methods(); 3719 mark_newly_obsolete_methods(old_methods, emcp_method_count); 3720 3721 // If the constant pool for this previous version of the class 3722 // is not marked as being on the stack, then none of the methods 3723 // in this previous version of the class are on the stack so 3724 // we don't need to add this as a previous version. 3725 ConstantPool* cp_ref = scratch_class->constants(); 3726 if (!cp_ref->on_stack()) { 3727 log_trace(redefine, class, iklass, add)("scratch class not added; no methods are running"); 3728 // For debugging purposes. 3729 scratch_class->set_is_scratch_class(); 3730 scratch_class->class_loader_data()->add_to_deallocate_list(scratch_class); 3731 return; 3732 } 3733 3734 if (emcp_method_count != 0) { 3735 // At least one method is still running, check for EMCP methods 3736 for (int i = 0; i < old_methods->length(); i++) { 3737 Method* old_method = old_methods->at(i); 3738 if (!old_method->is_obsolete() && old_method->on_stack()) { 3739 // if EMCP method (not obsolete) is on the stack, mark as EMCP so that 3740 // we can add breakpoints for it. 3741 3742 // We set the method->on_stack bit during safepoints for class redefinition 3743 // and use this bit to set the is_running_emcp bit. 3744 // After the safepoint, the on_stack bit is cleared and the running emcp 3745 // method may exit. If so, we would set a breakpoint in a method that 3746 // is never reached, but this won't be noticeable to the programmer. 3747 old_method->set_running_emcp(true); 3748 log_trace(redefine, class, iklass, add) 3749 ("EMCP method %s is on_stack " INTPTR_FORMAT, old_method->name_and_sig_as_C_string(), p2i(old_method)); 3750 } else if (!old_method->is_obsolete()) { 3751 log_trace(redefine, class, iklass, add) 3752 ("EMCP method %s is NOT on_stack " INTPTR_FORMAT, old_method->name_and_sig_as_C_string(), p2i(old_method)); 3753 } 3754 } 3755 } 3756 3757 // Add previous version if any methods are still running. 3758 // Set has_previous_version flag for processing during class unloading. 3759 _has_previous_versions = true; 3760 log_trace(redefine, class, iklass, add) ("scratch class added; one of its methods is on_stack."); 3761 assert(scratch_class->previous_versions() == NULL, "shouldn't have a previous version"); 3762 scratch_class->link_previous_versions(previous_versions()); 3763 link_previous_versions(scratch_class); 3764 } // end add_previous_version() 3765 3766 #endif // INCLUDE_JVMTI 3767 3768 Method* InstanceKlass::method_with_idnum(int idnum) { 3769 Method* m = NULL; 3770 if (idnum < methods()->length()) { 3771 m = methods()->at(idnum); 3772 } 3773 if (m == NULL || m->method_idnum() != idnum) { 3774 for (int index = 0; index < methods()->length(); ++index) { 3775 m = methods()->at(index); 3776 if (m->method_idnum() == idnum) { 3777 return m; 3778 } 3779 } 3780 // None found, return null for the caller to handle. 3781 return NULL; 3782 } 3783 return m; 3784 } 3785 3786 3787 Method* InstanceKlass::method_with_orig_idnum(int idnum) { 3788 if (idnum >= methods()->length()) { 3789 return NULL; 3790 } 3791 Method* m = methods()->at(idnum); 3792 if (m != NULL && m->orig_method_idnum() == idnum) { 3793 return m; 3794 } 3795 // Obsolete method idnum does not match the original idnum 3796 for (int index = 0; index < methods()->length(); ++index) { 3797 m = methods()->at(index); 3798 if (m->orig_method_idnum() == idnum) { 3799 return m; 3800 } 3801 } 3802 // None found, return null for the caller to handle. 3803 return NULL; 3804 } 3805 3806 3807 Method* InstanceKlass::method_with_orig_idnum(int idnum, int version) { 3808 InstanceKlass* holder = get_klass_version(version); 3809 if (holder == NULL) { 3810 return NULL; // The version of klass is gone, no method is found 3811 } 3812 Method* method = holder->method_with_orig_idnum(idnum); 3813 return method; 3814 } 3815 3816 #if INCLUDE_JVMTI 3817 JvmtiCachedClassFileData* InstanceKlass::get_cached_class_file() { 3818 if (MetaspaceShared::is_in_shared_space(_cached_class_file)) { 3819 // Ignore the archived class stream data 3820 return NULL; 3821 } else { 3822 return _cached_class_file; 3823 } 3824 } 3825 3826 jint InstanceKlass::get_cached_class_file_len() { 3827 return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file); 3828 } 3829 3830 unsigned char * InstanceKlass::get_cached_class_file_bytes() { 3831 return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file); 3832 } 3833 3834 #if INCLUDE_CDS 3835 JvmtiCachedClassFileData* InstanceKlass::get_archived_class_data() { 3836 assert(this->is_shared(), "class should be shared"); 3837 if (MetaspaceShared::is_in_shared_space(_cached_class_file)) { 3838 return _cached_class_file; 3839 } else { 3840 return NULL; 3841 } 3842 } 3843 #endif 3844 #endif 3845 3846 #define THROW_DVT_ERROR(s) \ 3847 Exceptions::fthrow(THREAD_AND_LOCATION, vmSymbols::java_lang_InternalError(), \ 3848 "DeriveValueType class '%s' %s", external_name(),(s)); \ 3849 return 3850 3851 void InstanceKlass::create_derive_value_type(Handle class_loader, Handle protection_domain, TRAPS) { 3852 ResourceMark rm(THREAD); 3853 HandleMark hm(THREAD); 3854 3855 if (!EnableMVT) { 3856 return; // Silent fail 3857 } 3858 // Validate VCC... 3859 if (!has_nonstatic_fields()) { 3860 THROW_DVT_ERROR("has no instance fields"); 3861 } 3862 if (is_value()) { 3863 THROW_DVT_ERROR("is already a value type"); 3864 } 3865 if (!access_flags().is_final()) { 3866 THROW_DVT_ERROR("is not a final class"); 3867 } 3868 if (super() != SystemDictionary::Object_klass()) { 3869 THROW_DVT_ERROR("does not derive from Object only"); 3870 } 3871 3872 // All non-static are final 3873 GrowableArray<Handle>* fields = new GrowableArray<Handle>(THREAD, java_fields_count()*2); 3874 GrowableArray<jint>* fields_access = new GrowableArray<jint>(THREAD, java_fields_count()*2); 3875 for (JavaFieldStream fs(this); !fs.done(); fs.next()) { 3876 AccessFlags access_flags = fs.access_flags(); 3877 if (access_flags.is_static()) { 3878 continue; 3879 } 3880 if (!access_flags.is_final()) { 3881 THROW_DVT_ERROR("contains non-final instance field"); 3882 } 3883 jint flags = access_flags.get_flags(); 3884 // Remember the field name, signature, access modifiers 3885 Handle h = java_lang_String::create_from_symbol(fs.name(), CHECK); 3886 fields->append(h); 3887 h = java_lang_String::create_from_symbol(fs.signature(), CHECK); 3888 fields->append(h); 3889 fields_access->append(access_flags.get_flags()); 3890 } 3891 3892 // Generate DVT... 3893 log_debug(load)("Cooking DVT for VCC %s", external_name()); 3894 const char* this_name = name()->as_C_string(); 3895 3896 // Assemble the Java args...field descriptor array 3897 objArrayOop fdarr_oop = oopFactory::new_objectArray(fields->length(), CHECK); 3898 objArrayHandle fdarr(THREAD, fdarr_oop); 3899 for (int i = 0; i < fields->length(); i++) { 3900 fdarr->obj_at_put(i, fields->at(i)()); 3901 } 3902 //...field access modifiers array 3903 typeArrayOop faarr_oop = oopFactory::new_intArray(fields_access->length(), CHECK); 3904 typeArrayHandle faarr(THREAD, faarr_oop); 3905 for (int i = 0; i < fields_access->length(); i++) { 3906 faarr->int_at_put(i, fields_access->at(i)); 3907 } 3908 3909 Handle vcc_name_h = java_lang_String::create_from_symbol(name(), CHECK); 3910 // Upcall to our Java helper... 3911 JavaValue result(T_OBJECT); 3912 JavaCallArguments args(5); 3913 args.push_oop(vcc_name_h); 3914 args.push_oop(class_loader); 3915 args.push_oop(protection_domain); 3916 args.push_oop(fdarr); 3917 args.push_oop(faarr); 3918 JavaCalls::call_static(&result, 3919 SystemDictionary::Valhalla_MVT1_0_klass(), 3920 vmSymbols::valhalla_shady_MVT1_0_createDerivedValueType(), 3921 vmSymbols::valhalla_shady_MVT1_0_createDerivedValueType_signature(), 3922 &args, 3923 CHECK); 3924 Handle returned(THREAD, (oop) result.get_jobject()); 3925 if (returned.is_null()) { 3926 THROW_DVT_ERROR("unknown error deriving value type"); 3927 } 3928 TempNewSymbol dvt_name_sym = java_lang_String::as_symbol(returned(), CHECK); 3929 3930 Klass* dvt_klass = SystemDictionary::resolve_or_null(dvt_name_sym, 3931 class_loader, 3932 protection_domain, 3933 CHECK); 3934 if (!dvt_klass->is_value()) { 3935 THROW_DVT_ERROR("failed to resolve derived value type"); 3936 } 3937 /** 3938 * Found it, let's point to each other to denote "is_derive_vt()"... 3939 */ 3940 ValueKlass* vt_klass = ValueKlass::cast(dvt_klass); 3941 assert(vt_klass->class_loader() == class_loader(), "DVT Not the same class loader as VCC"); 3942 vt_klass->set_vcc_klass(this); 3943 log_debug(load)("Cooked DVT %s for VCC %s", vt_klass->external_name(), external_name()); 3944 } 3945