1 /* 2 * Copyright (c) 1997, 2015, 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 "classfile/classFileParser.hpp" 27 #include "classfile/javaClasses.hpp" 28 #include "classfile/systemDictionary.hpp" 29 #include "classfile/verifier.hpp" 30 #include "classfile/vmSymbols.hpp" 31 #include "code/dependencyContext.hpp" 32 #include "compiler/compileBroker.hpp" 33 #include "gc/shared/collectedHeap.inline.hpp" 34 #include "gc/shared/specialized_oop_closures.hpp" 35 #include "interpreter/oopMapCache.hpp" 36 #include "interpreter/rewriter.hpp" 37 #include "jvmtifiles/jvmti.h" 38 #include "memory/heapInspection.hpp" 39 #include "memory/iterator.inline.hpp" 40 #include "memory/metadataFactory.hpp" 41 #include "memory/oopFactory.hpp" 42 #include "oops/fieldStreams.hpp" 43 #include "oops/instanceClassLoaderKlass.hpp" 44 #include "oops/instanceKlass.inline.hpp" 45 #include "oops/instanceMirrorKlass.hpp" 46 #include "oops/instanceOop.hpp" 47 #include "oops/klass.inline.hpp" 48 #include "oops/method.hpp" 49 #include "oops/oop.inline.hpp" 50 #include "oops/symbol.hpp" 51 #include "prims/jvmtiExport.hpp" 52 #include "prims/jvmtiRedefineClasses.hpp" 53 #include "prims/jvmtiRedefineClassesTrace.hpp" 54 #include "prims/jvmtiThreadState.hpp" 55 #include "prims/methodComparator.hpp" 56 #include "runtime/atomic.inline.hpp" 57 #include "runtime/fieldDescriptor.hpp" 58 #include "runtime/handles.inline.hpp" 59 #include "runtime/javaCalls.hpp" 60 #include "runtime/mutexLocker.hpp" 61 #include "runtime/orderAccess.inline.hpp" 62 #include "runtime/thread.inline.hpp" 63 #include "services/classLoadingService.hpp" 64 #include "services/threadService.hpp" 65 #include "utilities/dtrace.hpp" 66 #include "utilities/macros.hpp" 67 #include "logging/log.hpp" 68 #ifdef COMPILER1 69 #include "c1/c1_Compiler.hpp" 70 #endif 71 72 #ifdef DTRACE_ENABLED 73 74 75 #define HOTSPOT_CLASS_INITIALIZATION_required HOTSPOT_CLASS_INITIALIZATION_REQUIRED 76 #define HOTSPOT_CLASS_INITIALIZATION_recursive HOTSPOT_CLASS_INITIALIZATION_RECURSIVE 77 #define HOTSPOT_CLASS_INITIALIZATION_concurrent HOTSPOT_CLASS_INITIALIZATION_CONCURRENT 78 #define HOTSPOT_CLASS_INITIALIZATION_erroneous HOTSPOT_CLASS_INITIALIZATION_ERRONEOUS 79 #define HOTSPOT_CLASS_INITIALIZATION_super__failed HOTSPOT_CLASS_INITIALIZATION_SUPER_FAILED 80 #define HOTSPOT_CLASS_INITIALIZATION_clinit HOTSPOT_CLASS_INITIALIZATION_CLINIT 81 #define HOTSPOT_CLASS_INITIALIZATION_error HOTSPOT_CLASS_INITIALIZATION_ERROR 82 #define HOTSPOT_CLASS_INITIALIZATION_end HOTSPOT_CLASS_INITIALIZATION_END 83 #define DTRACE_CLASSINIT_PROBE(type, clss, thread_type) \ 84 { \ 85 char* data = NULL; \ 86 int len = 0; \ 87 Symbol* name = (clss)->name(); \ 88 if (name != NULL) { \ 89 data = (char*)name->bytes(); \ 90 len = name->utf8_length(); \ 91 } \ 92 HOTSPOT_CLASS_INITIALIZATION_##type( \ 93 data, len, (clss)->class_loader(), thread_type); \ 94 } 95 96 #define DTRACE_CLASSINIT_PROBE_WAIT(type, clss, thread_type, wait) \ 97 { \ 98 char* data = NULL; \ 99 int len = 0; \ 100 Symbol* name = (clss)->name(); \ 101 if (name != NULL) { \ 102 data = (char*)name->bytes(); \ 103 len = name->utf8_length(); \ 104 } \ 105 HOTSPOT_CLASS_INITIALIZATION_##type( \ 106 data, len, (clss)->class_loader(), thread_type, wait); \ 107 } 108 109 #else // ndef DTRACE_ENABLED 110 111 #define DTRACE_CLASSINIT_PROBE(type, clss, thread_type) 112 #define DTRACE_CLASSINIT_PROBE_WAIT(type, clss, thread_type, wait) 113 114 #endif // ndef DTRACE_ENABLED 115 116 volatile int InstanceKlass::_total_instanceKlass_count = 0; 117 118 static inline bool is_class_loader(const Symbol* class_name, 119 const ClassFileParser& parser) { 120 assert(class_name != NULL, "invariant"); 121 122 if (class_name == vmSymbols::java_lang_ClassLoader()) { 123 return true; 124 } 125 126 if (SystemDictionary::ClassLoader_klass_loaded()) { 127 const Klass* const super_klass = parser.super_klass(); 128 if (super_klass != NULL) { 129 if (super_klass->is_subtype_of(SystemDictionary::ClassLoader_klass())) { 130 return true; 131 } 132 } 133 } 134 return false; 135 } 136 137 InstanceKlass* InstanceKlass::allocate_instance_klass(const ClassFileParser& parser, TRAPS) { 138 const int size = InstanceKlass::size(parser.vtable_size(), 139 parser.itable_size(), 140 nonstatic_oop_map_size(parser.total_oop_map_count()), 141 parser.is_interface(), 142 parser.is_anonymous()); 143 144 const Symbol* const class_name = parser.class_name(); 145 assert(class_name != NULL, "invariant"); 146 ClassLoaderData* loader_data = parser.loader_data(); 147 assert(loader_data != NULL, "invariant"); 148 149 InstanceKlass* ik; 150 151 // Allocation 152 if (REF_NONE == parser.reference_type()) { 153 if (class_name == vmSymbols::java_lang_Class()) { 154 // mirror 155 ik = new (loader_data, size, THREAD) InstanceMirrorKlass(parser); 156 } 157 else if (is_class_loader(class_name, parser)) { 158 // class loader 159 ik = new (loader_data, size, THREAD) InstanceClassLoaderKlass(parser); 160 } 161 else { 162 // normal 163 ik = new (loader_data, size, THREAD) InstanceKlass(parser, InstanceKlass::_misc_kind_other); 164 } 165 } 166 else { 167 // reference 168 ik = new (loader_data, size, THREAD) InstanceRefKlass(parser); 169 } 170 171 // Check for pending exception before adding to the loader data and incrementing 172 // class count. Can get OOM here. 173 if (HAS_PENDING_EXCEPTION) { 174 return NULL; 175 } 176 177 assert(ik != NULL, "invariant"); 178 179 const bool publicize = !parser.is_internal(); 180 181 // Add all classes to our internal class loader list here, 182 // including classes in the bootstrap (NULL) class loader. 183 loader_data->add_class(ik, publicize); 184 Atomic::inc(&_total_instanceKlass_count); 185 186 return ik; 187 } 188 189 190 // copy method ordering from resource area to Metaspace 191 void InstanceKlass::copy_method_ordering(const intArray* m, TRAPS) { 192 if (m != NULL) { 193 // allocate a new array and copy contents (memcpy?) 194 _method_ordering = MetadataFactory::new_array<int>(class_loader_data(), m->length(), CHECK); 195 for (int i = 0; i < m->length(); i++) { 196 _method_ordering->at_put(i, m->at(i)); 197 } 198 } else { 199 _method_ordering = Universe::the_empty_int_array(); 200 } 201 } 202 203 // create a new array of vtable_indices for default methods 204 Array<int>* InstanceKlass::create_new_default_vtable_indices(int len, TRAPS) { 205 Array<int>* vtable_indices = MetadataFactory::new_array<int>(class_loader_data(), len, CHECK_NULL); 206 assert(default_vtable_indices() == NULL, "only create once"); 207 set_default_vtable_indices(vtable_indices); 208 return vtable_indices; 209 } 210 211 InstanceKlass::InstanceKlass(const ClassFileParser& parser, unsigned kind) : 212 _static_field_size(parser.static_field_size()), 213 _nonstatic_oop_map_size(nonstatic_oop_map_size(parser.total_oop_map_count())), 214 _vtable_len(parser.vtable_size()), 215 _itable_len(parser.itable_size()), 216 _reference_type(parser.reference_type()) { 217 set_kind(kind); 218 set_access_flags(parser.access_flags()); 219 set_is_anonymous(parser.is_anonymous()); 220 set_layout_helper(Klass::instance_layout_helper(parser.layout_size(), 221 false)); 222 223 assert(NULL == _methods, "underlying memory not zeroed?"); 224 assert(is_instance_klass(), "is layout incorrect?"); 225 assert(size_helper() == parser.layout_size(), "incorrect size_helper?"); 226 } 227 228 void InstanceKlass::deallocate_methods(ClassLoaderData* loader_data, 229 Array<Method*>* methods) { 230 if (methods != NULL && methods != Universe::the_empty_method_array() && 231 !methods->is_shared()) { 232 for (int i = 0; i < methods->length(); i++) { 233 Method* method = methods->at(i); 234 if (method == NULL) continue; // maybe null if error processing 235 // Only want to delete methods that are not executing for RedefineClasses. 236 // The previous version will point to them so they're not totally dangling 237 assert (!method->on_stack(), "shouldn't be called with methods on stack"); 238 MetadataFactory::free_metadata(loader_data, method); 239 } 240 MetadataFactory::free_array<Method*>(loader_data, methods); 241 } 242 } 243 244 void InstanceKlass::deallocate_interfaces(ClassLoaderData* loader_data, 245 const Klass* super_klass, 246 Array<Klass*>* local_interfaces, 247 Array<Klass*>* transitive_interfaces) { 248 // Only deallocate transitive interfaces if not empty, same as super class 249 // or same as local interfaces. See code in parseClassFile. 250 Array<Klass*>* ti = transitive_interfaces; 251 if (ti != Universe::the_empty_klass_array() && ti != local_interfaces) { 252 // check that the interfaces don't come from super class 253 Array<Klass*>* sti = (super_klass == NULL) ? NULL : 254 InstanceKlass::cast(super_klass)->transitive_interfaces(); 255 if (ti != sti && ti != NULL && !ti->is_shared()) { 256 MetadataFactory::free_array<Klass*>(loader_data, ti); 257 } 258 } 259 260 // local interfaces can be empty 261 if (local_interfaces != Universe::the_empty_klass_array() && 262 local_interfaces != NULL && !local_interfaces->is_shared()) { 263 MetadataFactory::free_array<Klass*>(loader_data, local_interfaces); 264 } 265 } 266 267 // This function deallocates the metadata and C heap pointers that the 268 // InstanceKlass points to. 269 void InstanceKlass::deallocate_contents(ClassLoaderData* loader_data) { 270 271 // Orphan the mirror first, CMS thinks it's still live. 272 if (java_mirror() != NULL) { 273 java_lang_Class::set_klass(java_mirror(), NULL); 274 } 275 276 // Need to take this class off the class loader data list. 277 loader_data->remove_class(this); 278 279 // The array_klass for this class is created later, after error handling. 280 // For class redefinition, we keep the original class so this scratch class 281 // doesn't have an array class. Either way, assert that there is nothing 282 // to deallocate. 283 assert(array_klasses() == NULL, "array classes shouldn't be created for this class yet"); 284 285 // Release C heap allocated data that this might point to, which includes 286 // reference counting symbol names. 287 release_C_heap_structures(); 288 289 deallocate_methods(loader_data, methods()); 290 set_methods(NULL); 291 292 if (method_ordering() != NULL && 293 method_ordering() != Universe::the_empty_int_array() && 294 !method_ordering()->is_shared()) { 295 MetadataFactory::free_array<int>(loader_data, method_ordering()); 296 } 297 set_method_ordering(NULL); 298 299 // default methods can be empty 300 if (default_methods() != NULL && 301 default_methods() != Universe::the_empty_method_array() && 302 !default_methods()->is_shared()) { 303 MetadataFactory::free_array<Method*>(loader_data, default_methods()); 304 } 305 // Do NOT deallocate the default methods, they are owned by superinterfaces. 306 set_default_methods(NULL); 307 308 // default methods vtable indices can be empty 309 if (default_vtable_indices() != NULL && 310 !default_vtable_indices()->is_shared()) { 311 MetadataFactory::free_array<int>(loader_data, default_vtable_indices()); 312 } 313 set_default_vtable_indices(NULL); 314 315 316 // This array is in Klass, but remove it with the InstanceKlass since 317 // this place would be the only caller and it can share memory with transitive 318 // interfaces. 319 if (secondary_supers() != NULL && 320 secondary_supers() != Universe::the_empty_klass_array() && 321 secondary_supers() != transitive_interfaces() && 322 !secondary_supers()->is_shared()) { 323 MetadataFactory::free_array<Klass*>(loader_data, secondary_supers()); 324 } 325 set_secondary_supers(NULL); 326 327 deallocate_interfaces(loader_data, super(), local_interfaces(), transitive_interfaces()); 328 set_transitive_interfaces(NULL); 329 set_local_interfaces(NULL); 330 331 if (fields() != NULL && !fields()->is_shared()) { 332 MetadataFactory::free_array<jushort>(loader_data, fields()); 333 } 334 set_fields(NULL, 0); 335 336 // If a method from a redefined class is using this constant pool, don't 337 // delete it, yet. The new class's previous version will point to this. 338 if (constants() != NULL) { 339 assert (!constants()->on_stack(), "shouldn't be called if anything is onstack"); 340 if (!constants()->is_shared()) { 341 MetadataFactory::free_metadata(loader_data, constants()); 342 } 343 // Delete any cached resolution errors for the constant pool 344 SystemDictionary::delete_resolution_error(constants()); 345 346 set_constants(NULL); 347 } 348 349 if (inner_classes() != NULL && 350 inner_classes() != Universe::the_empty_short_array() && 351 !inner_classes()->is_shared()) { 352 MetadataFactory::free_array<jushort>(loader_data, inner_classes()); 353 } 354 set_inner_classes(NULL); 355 356 // We should deallocate the Annotations instance if it's not in shared spaces. 357 if (annotations() != NULL && !annotations()->is_shared()) { 358 MetadataFactory::free_metadata(loader_data, annotations()); 359 } 360 set_annotations(NULL); 361 } 362 363 bool InstanceKlass::should_be_initialized() const { 364 return !is_initialized(); 365 } 366 367 klassVtable* InstanceKlass::vtable() const { 368 return new klassVtable(this, start_of_vtable(), vtable_length() / vtableEntry::size()); 369 } 370 371 klassItable* InstanceKlass::itable() const { 372 return new klassItable(instanceKlassHandle(this)); 373 } 374 375 void InstanceKlass::eager_initialize(Thread *thread) { 376 if (!EagerInitialization) return; 377 378 if (this->is_not_initialized()) { 379 // abort if the the class has a class initializer 380 if (this->class_initializer() != NULL) return; 381 382 // abort if it is java.lang.Object (initialization is handled in genesis) 383 Klass* super = this->super(); 384 if (super == NULL) return; 385 386 // abort if the super class should be initialized 387 if (!InstanceKlass::cast(super)->is_initialized()) return; 388 389 // call body to expose the this pointer 390 instanceKlassHandle this_k(thread, this); 391 eager_initialize_impl(this_k); 392 } 393 } 394 395 // JVMTI spec thinks there are signers and protection domain in the 396 // instanceKlass. These accessors pretend these fields are there. 397 // The hprof specification also thinks these fields are in InstanceKlass. 398 oop InstanceKlass::protection_domain() const { 399 // return the protection_domain from the mirror 400 return java_lang_Class::protection_domain(java_mirror()); 401 } 402 403 // To remove these from requires an incompatible change and CCC request. 404 objArrayOop InstanceKlass::signers() const { 405 // return the signers from the mirror 406 return java_lang_Class::signers(java_mirror()); 407 } 408 409 oop InstanceKlass::init_lock() const { 410 // return the init lock from the mirror 411 oop lock = java_lang_Class::init_lock(java_mirror()); 412 // Prevent reordering with any access of initialization state 413 OrderAccess::loadload(); 414 assert((oop)lock != NULL || !is_not_initialized(), // initialized or in_error state 415 "only fully initialized state can have a null lock"); 416 return lock; 417 } 418 419 // Set the initialization lock to null so the object can be GC'ed. Any racing 420 // threads to get this lock will see a null lock and will not lock. 421 // That's okay because they all check for initialized state after getting 422 // the lock and return. 423 void InstanceKlass::fence_and_clear_init_lock() { 424 // make sure previous stores are all done, notably the init_state. 425 OrderAccess::storestore(); 426 java_lang_Class::set_init_lock(java_mirror(), NULL); 427 assert(!is_not_initialized(), "class must be initialized now"); 428 } 429 430 void InstanceKlass::eager_initialize_impl(instanceKlassHandle this_k) { 431 EXCEPTION_MARK; 432 oop init_lock = this_k->init_lock(); 433 ObjectLocker ol(init_lock, THREAD, init_lock != NULL); 434 435 // abort if someone beat us to the initialization 436 if (!this_k->is_not_initialized()) return; // note: not equivalent to is_initialized() 437 438 ClassState old_state = this_k->init_state(); 439 link_class_impl(this_k, true, THREAD); 440 if (HAS_PENDING_EXCEPTION) { 441 CLEAR_PENDING_EXCEPTION; 442 // Abort if linking the class throws an exception. 443 444 // Use a test to avoid redundantly resetting the state if there's 445 // no change. Set_init_state() asserts that state changes make 446 // progress, whereas here we might just be spinning in place. 447 if( old_state != this_k->_init_state ) 448 this_k->set_init_state (old_state); 449 } else { 450 // linking successfull, mark class as initialized 451 this_k->set_init_state (fully_initialized); 452 this_k->fence_and_clear_init_lock(); 453 // trace 454 if (log_is_enabled(Info, classinit)) { 455 ResourceMark rm(THREAD); 456 log_info(classinit)("[Initialized %s without side effects]", this_k->external_name()); 457 } 458 } 459 } 460 461 462 // See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization 463 // process. The step comments refers to the procedure described in that section. 464 // Note: implementation moved to static method to expose the this pointer. 465 void InstanceKlass::initialize(TRAPS) { 466 if (this->should_be_initialized()) { 467 HandleMark hm(THREAD); 468 instanceKlassHandle this_k(THREAD, this); 469 initialize_impl(this_k, CHECK); 470 // Note: at this point the class may be initialized 471 // OR it may be in the state of being initialized 472 // in case of recursive initialization! 473 } else { 474 assert(is_initialized(), "sanity check"); 475 } 476 } 477 478 479 bool InstanceKlass::verify_code( 480 instanceKlassHandle this_k, bool throw_verifyerror, TRAPS) { 481 // 1) Verify the bytecodes 482 Verifier::Mode mode = 483 throw_verifyerror ? Verifier::ThrowException : Verifier::NoException; 484 return Verifier::verify(this_k, mode, this_k->should_verify_class(), THREAD); 485 } 486 487 488 // Used exclusively by the shared spaces dump mechanism to prevent 489 // classes mapped into the shared regions in new VMs from appearing linked. 490 491 void InstanceKlass::unlink_class() { 492 assert(is_linked(), "must be linked"); 493 _init_state = loaded; 494 } 495 496 void InstanceKlass::link_class(TRAPS) { 497 assert(is_loaded(), "must be loaded"); 498 if (!is_linked()) { 499 HandleMark hm(THREAD); 500 instanceKlassHandle this_k(THREAD, this); 501 link_class_impl(this_k, true, CHECK); 502 } 503 } 504 505 // Called to verify that a class can link during initialization, without 506 // throwing a VerifyError. 507 bool InstanceKlass::link_class_or_fail(TRAPS) { 508 assert(is_loaded(), "must be loaded"); 509 if (!is_linked()) { 510 HandleMark hm(THREAD); 511 instanceKlassHandle this_k(THREAD, this); 512 link_class_impl(this_k, false, CHECK_false); 513 } 514 return is_linked(); 515 } 516 517 bool InstanceKlass::link_class_impl( 518 instanceKlassHandle this_k, bool throw_verifyerror, TRAPS) { 519 // check for error state 520 if (this_k->is_in_error_state()) { 521 ResourceMark rm(THREAD); 522 THROW_MSG_(vmSymbols::java_lang_NoClassDefFoundError(), 523 this_k->external_name(), false); 524 } 525 // return if already verified 526 if (this_k->is_linked()) { 527 return true; 528 } 529 530 // Timing 531 // timer handles recursion 532 assert(THREAD->is_Java_thread(), "non-JavaThread in link_class_impl"); 533 JavaThread* jt = (JavaThread*)THREAD; 534 535 // link super class before linking this class 536 instanceKlassHandle super(THREAD, this_k->super()); 537 if (super.not_null()) { 538 if (super->is_interface()) { // check if super class is an interface 539 ResourceMark rm(THREAD); 540 Exceptions::fthrow( 541 THREAD_AND_LOCATION, 542 vmSymbols::java_lang_IncompatibleClassChangeError(), 543 "class %s has interface %s as super class", 544 this_k->external_name(), 545 super->external_name() 546 ); 547 return false; 548 } 549 550 link_class_impl(super, throw_verifyerror, CHECK_false); 551 } 552 553 // link all interfaces implemented by this class before linking this class 554 Array<Klass*>* interfaces = this_k->local_interfaces(); 555 int num_interfaces = interfaces->length(); 556 for (int index = 0; index < num_interfaces; index++) { 557 HandleMark hm(THREAD); 558 instanceKlassHandle ih(THREAD, interfaces->at(index)); 559 link_class_impl(ih, throw_verifyerror, CHECK_false); 560 } 561 562 // in case the class is linked in the process of linking its superclasses 563 if (this_k->is_linked()) { 564 return true; 565 } 566 567 // trace only the link time for this klass that includes 568 // the verification time 569 PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(), 570 ClassLoader::perf_class_link_selftime(), 571 ClassLoader::perf_classes_linked(), 572 jt->get_thread_stat()->perf_recursion_counts_addr(), 573 jt->get_thread_stat()->perf_timers_addr(), 574 PerfClassTraceTime::CLASS_LINK); 575 576 // verification & rewriting 577 { 578 oop init_lock = this_k->init_lock(); 579 ObjectLocker ol(init_lock, THREAD, init_lock != NULL); 580 // rewritten will have been set if loader constraint error found 581 // on an earlier link attempt 582 // don't verify or rewrite if already rewritten 583 584 if (!this_k->is_linked()) { 585 if (!this_k->is_rewritten()) { 586 { 587 bool verify_ok = verify_code(this_k, throw_verifyerror, THREAD); 588 if (!verify_ok) { 589 return false; 590 } 591 } 592 593 // Just in case a side-effect of verify linked this class already 594 // (which can sometimes happen since the verifier loads classes 595 // using custom class loaders, which are free to initialize things) 596 if (this_k->is_linked()) { 597 return true; 598 } 599 600 // also sets rewritten 601 this_k->rewrite_class(CHECK_false); 602 } 603 604 // relocate jsrs and link methods after they are all rewritten 605 this_k->link_methods(CHECK_false); 606 607 // Initialize the vtable and interface table after 608 // methods have been rewritten since rewrite may 609 // fabricate new Method*s. 610 // also does loader constraint checking 611 if (!this_k()->is_shared()) { 612 ResourceMark rm(THREAD); 613 this_k->vtable()->initialize_vtable(true, CHECK_false); 614 this_k->itable()->initialize_itable(true, CHECK_false); 615 } 616 #ifdef ASSERT 617 else { 618 ResourceMark rm(THREAD); 619 this_k->vtable()->verify(tty, true); 620 // In case itable verification is ever added. 621 // this_k->itable()->verify(tty, true); 622 } 623 #endif 624 this_k->set_init_state(linked); 625 if (JvmtiExport::should_post_class_prepare()) { 626 Thread *thread = THREAD; 627 assert(thread->is_Java_thread(), "thread->is_Java_thread()"); 628 JvmtiExport::post_class_prepare((JavaThread *) thread, this_k()); 629 } 630 } 631 } 632 return true; 633 } 634 635 636 // Rewrite the byte codes of all of the methods of a class. 637 // The rewriter must be called exactly once. Rewriting must happen after 638 // verification but before the first method of the class is executed. 639 void InstanceKlass::rewrite_class(TRAPS) { 640 assert(is_loaded(), "must be loaded"); 641 instanceKlassHandle this_k(THREAD, this); 642 if (this_k->is_rewritten()) { 643 assert(this_k()->is_shared(), "rewriting an unshared class?"); 644 return; 645 } 646 Rewriter::rewrite(this_k, CHECK); 647 this_k->set_rewritten(); 648 } 649 650 // Now relocate and link method entry points after class is rewritten. 651 // This is outside is_rewritten flag. In case of an exception, it can be 652 // executed more than once. 653 void InstanceKlass::link_methods(TRAPS) { 654 int len = methods()->length(); 655 for (int i = len-1; i >= 0; i--) { 656 methodHandle m(THREAD, methods()->at(i)); 657 658 // Set up method entry points for compiler and interpreter . 659 m->link_method(m, CHECK); 660 } 661 } 662 663 // Eagerly initialize superinterfaces that declare default methods (concrete instance: any access) 664 void InstanceKlass::initialize_super_interfaces(instanceKlassHandle this_k, TRAPS) { 665 if (this_k->has_default_methods()) { 666 for (int i = 0; i < this_k->local_interfaces()->length(); ++i) { 667 Klass* iface = this_k->local_interfaces()->at(i); 668 InstanceKlass* ik = InstanceKlass::cast(iface); 669 if (ik->should_be_initialized()) { 670 if (ik->has_default_methods()) { 671 ik->initialize_super_interfaces(ik, THREAD); 672 } 673 // Only initialize() interfaces that "declare" concrete methods. 674 // has_default_methods drives searching superinterfaces since it 675 // means has_default_methods in its superinterface hierarchy 676 if (!HAS_PENDING_EXCEPTION && ik->declares_default_methods()) { 677 ik->initialize(THREAD); 678 } 679 if (HAS_PENDING_EXCEPTION) { 680 Handle e(THREAD, PENDING_EXCEPTION); 681 CLEAR_PENDING_EXCEPTION; 682 { 683 EXCEPTION_MARK; 684 // Locks object, set state, and notify all waiting threads 685 this_k->set_initialization_state_and_notify( 686 initialization_error, THREAD); 687 688 // ignore any exception thrown, superclass initialization error is 689 // thrown below 690 CLEAR_PENDING_EXCEPTION; 691 } 692 THROW_OOP(e()); 693 } 694 } 695 } 696 } 697 } 698 699 void InstanceKlass::initialize_impl(instanceKlassHandle this_k, TRAPS) { 700 // Make sure klass is linked (verified) before initialization 701 // A class could already be verified, since it has been reflected upon. 702 this_k->link_class(CHECK); 703 704 DTRACE_CLASSINIT_PROBE(required, this_k(), -1); 705 706 bool wait = false; 707 708 // refer to the JVM book page 47 for description of steps 709 // Step 1 710 { 711 oop init_lock = this_k->init_lock(); 712 ObjectLocker ol(init_lock, THREAD, init_lock != NULL); 713 714 Thread *self = THREAD; // it's passed the current thread 715 716 // Step 2 717 // If we were to use wait() instead of waitInterruptibly() then 718 // we might end up throwing IE from link/symbol resolution sites 719 // that aren't expected to throw. This would wreak havoc. See 6320309. 720 while(this_k->is_being_initialized() && !this_k->is_reentrant_initialization(self)) { 721 wait = true; 722 ol.waitUninterruptibly(CHECK); 723 } 724 725 // Step 3 726 if (this_k->is_being_initialized() && this_k->is_reentrant_initialization(self)) { 727 DTRACE_CLASSINIT_PROBE_WAIT(recursive, this_k(), -1,wait); 728 return; 729 } 730 731 // Step 4 732 if (this_k->is_initialized()) { 733 DTRACE_CLASSINIT_PROBE_WAIT(concurrent, this_k(), -1,wait); 734 return; 735 } 736 737 // Step 5 738 if (this_k->is_in_error_state()) { 739 DTRACE_CLASSINIT_PROBE_WAIT(erroneous, this_k(), -1,wait); 740 ResourceMark rm(THREAD); 741 const char* desc = "Could not initialize class "; 742 const char* className = this_k->external_name(); 743 size_t msglen = strlen(desc) + strlen(className) + 1; 744 char* message = NEW_RESOURCE_ARRAY(char, msglen); 745 if (NULL == message) { 746 // Out of memory: can't create detailed error message 747 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), className); 748 } else { 749 jio_snprintf(message, msglen, "%s%s", desc, className); 750 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), message); 751 } 752 } 753 754 // Step 6 755 this_k->set_init_state(being_initialized); 756 this_k->set_init_thread(self); 757 } 758 759 // Step 7 760 Klass* super_klass = this_k->super(); 761 if (super_klass != NULL && !this_k->is_interface() && super_klass->should_be_initialized()) { 762 super_klass->initialize(THREAD); 763 764 if (HAS_PENDING_EXCEPTION) { 765 Handle e(THREAD, PENDING_EXCEPTION); 766 CLEAR_PENDING_EXCEPTION; 767 { 768 EXCEPTION_MARK; 769 this_k->set_initialization_state_and_notify(initialization_error, THREAD); // Locks object, set state, and notify all waiting threads 770 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, superclass initialization error is thrown below 771 } 772 DTRACE_CLASSINIT_PROBE_WAIT(super__failed, this_k(), -1,wait); 773 THROW_OOP(e()); 774 } 775 } 776 777 // If C is an interface that declares a non-abstract, non-static method, 778 // the initialization of a class (not an interface) that implements C directly or 779 // indirectly. 780 // Recursively initialize any superinterfaces that declare default methods 781 // Only need to recurse if has_default_methods which includes declaring and 782 // inheriting default methods 783 if (!this_k->is_interface() && this_k->has_default_methods()) { 784 this_k->initialize_super_interfaces(this_k, CHECK); 785 } 786 787 // Step 8 788 { 789 assert(THREAD->is_Java_thread(), "non-JavaThread in initialize_impl"); 790 JavaThread* jt = (JavaThread*)THREAD; 791 DTRACE_CLASSINIT_PROBE_WAIT(clinit, this_k(), -1,wait); 792 // Timer includes any side effects of class initialization (resolution, 793 // etc), but not recursive entry into call_class_initializer(). 794 PerfClassTraceTime timer(ClassLoader::perf_class_init_time(), 795 ClassLoader::perf_class_init_selftime(), 796 ClassLoader::perf_classes_inited(), 797 jt->get_thread_stat()->perf_recursion_counts_addr(), 798 jt->get_thread_stat()->perf_timers_addr(), 799 PerfClassTraceTime::CLASS_CLINIT); 800 this_k->call_class_initializer(THREAD); 801 } 802 803 // Step 9 804 if (!HAS_PENDING_EXCEPTION) { 805 this_k->set_initialization_state_and_notify(fully_initialized, CHECK); 806 { ResourceMark rm(THREAD); 807 debug_only(this_k->vtable()->verify(tty, true);) 808 } 809 } 810 else { 811 // Step 10 and 11 812 Handle e(THREAD, PENDING_EXCEPTION); 813 CLEAR_PENDING_EXCEPTION; 814 // JVMTI has already reported the pending exception 815 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError 816 JvmtiExport::clear_detected_exception((JavaThread*)THREAD); 817 { 818 EXCEPTION_MARK; 819 this_k->set_initialization_state_and_notify(initialization_error, THREAD); 820 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, class initialization error is thrown below 821 // JVMTI has already reported the pending exception 822 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError 823 JvmtiExport::clear_detected_exception((JavaThread*)THREAD); 824 } 825 DTRACE_CLASSINIT_PROBE_WAIT(error, this_k(), -1,wait); 826 if (e->is_a(SystemDictionary::Error_klass())) { 827 THROW_OOP(e()); 828 } else { 829 JavaCallArguments args(e); 830 THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(), 831 vmSymbols::throwable_void_signature(), 832 &args); 833 } 834 } 835 DTRACE_CLASSINIT_PROBE_WAIT(end, this_k(), -1,wait); 836 } 837 838 839 // Note: implementation moved to static method to expose the this pointer. 840 void InstanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) { 841 instanceKlassHandle kh(THREAD, this); 842 set_initialization_state_and_notify_impl(kh, state, CHECK); 843 } 844 845 void InstanceKlass::set_initialization_state_and_notify_impl(instanceKlassHandle this_k, ClassState state, TRAPS) { 846 oop init_lock = this_k->init_lock(); 847 ObjectLocker ol(init_lock, THREAD, init_lock != NULL); 848 this_k->set_init_state(state); 849 this_k->fence_and_clear_init_lock(); 850 ol.notify_all(CHECK); 851 } 852 853 // The embedded _implementor field can only record one implementor. 854 // When there are more than one implementors, the _implementor field 855 // is set to the interface Klass* itself. Following are the possible 856 // values for the _implementor field: 857 // NULL - no implementor 858 // implementor Klass* - one implementor 859 // self - more than one implementor 860 // 861 // The _implementor field only exists for interfaces. 862 void InstanceKlass::add_implementor(Klass* k) { 863 assert(Compile_lock->owned_by_self(), ""); 864 assert(is_interface(), "not interface"); 865 // Filter out my subinterfaces. 866 // (Note: Interfaces are never on the subklass list.) 867 if (InstanceKlass::cast(k)->is_interface()) return; 868 869 // Filter out subclasses whose supers already implement me. 870 // (Note: CHA must walk subclasses of direct implementors 871 // in order to locate indirect implementors.) 872 Klass* sk = k->super(); 873 if (sk != NULL && InstanceKlass::cast(sk)->implements_interface(this)) 874 // We only need to check one immediate superclass, since the 875 // implements_interface query looks at transitive_interfaces. 876 // Any supers of the super have the same (or fewer) transitive_interfaces. 877 return; 878 879 Klass* ik = implementor(); 880 if (ik == NULL) { 881 set_implementor(k); 882 } else if (ik != this) { 883 // There is already an implementor. Use itself as an indicator of 884 // more than one implementors. 885 set_implementor(this); 886 } 887 888 // The implementor also implements the transitive_interfaces 889 for (int index = 0; index < local_interfaces()->length(); index++) { 890 InstanceKlass::cast(local_interfaces()->at(index))->add_implementor(k); 891 } 892 } 893 894 void InstanceKlass::init_implementor() { 895 if (is_interface()) { 896 set_implementor(NULL); 897 } 898 } 899 900 901 void InstanceKlass::process_interfaces(Thread *thread) { 902 // link this class into the implementors list of every interface it implements 903 for (int i = local_interfaces()->length() - 1; i >= 0; i--) { 904 assert(local_interfaces()->at(i)->is_klass(), "must be a klass"); 905 InstanceKlass* interf = InstanceKlass::cast(local_interfaces()->at(i)); 906 assert(interf->is_interface(), "expected interface"); 907 interf->add_implementor(this); 908 } 909 } 910 911 bool InstanceKlass::can_be_primary_super_slow() const { 912 if (is_interface()) 913 return false; 914 else 915 return Klass::can_be_primary_super_slow(); 916 } 917 918 GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots) { 919 // The secondaries are the implemented interfaces. 920 Array<Klass*>* interfaces = transitive_interfaces(); 921 int num_secondaries = num_extra_slots + interfaces->length(); 922 if (num_secondaries == 0) { 923 // Must share this for correct bootstrapping! 924 set_secondary_supers(Universe::the_empty_klass_array()); 925 return NULL; 926 } else if (num_extra_slots == 0) { 927 // The secondary super list is exactly the same as the transitive interfaces. 928 // Redefine classes has to be careful not to delete this! 929 set_secondary_supers(interfaces); 930 return NULL; 931 } else { 932 // Copy transitive interfaces to a temporary growable array to be constructed 933 // into the secondary super list with extra slots. 934 GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length()); 935 for (int i = 0; i < interfaces->length(); i++) { 936 secondaries->push(interfaces->at(i)); 937 } 938 return secondaries; 939 } 940 } 941 942 bool InstanceKlass::compute_is_subtype_of(Klass* k) { 943 if (k->is_interface()) { 944 return implements_interface(k); 945 } else { 946 return Klass::compute_is_subtype_of(k); 947 } 948 } 949 950 bool InstanceKlass::implements_interface(Klass* k) const { 951 if (this == k) return true; 952 assert(k->is_interface(), "should be an interface class"); 953 for (int i = 0; i < transitive_interfaces()->length(); i++) { 954 if (transitive_interfaces()->at(i) == k) { 955 return true; 956 } 957 } 958 return false; 959 } 960 961 bool InstanceKlass::is_same_or_direct_interface(Klass *k) const { 962 // Verify direct super interface 963 if (this == k) return true; 964 assert(k->is_interface(), "should be an interface class"); 965 for (int i = 0; i < local_interfaces()->length(); i++) { 966 if (local_interfaces()->at(i) == k) { 967 return true; 968 } 969 } 970 return false; 971 } 972 973 objArrayOop InstanceKlass::allocate_objArray(int n, int length, TRAPS) { 974 if (length < 0) THROW_0(vmSymbols::java_lang_NegativeArraySizeException()); 975 if (length > arrayOopDesc::max_array_length(T_OBJECT)) { 976 report_java_out_of_memory("Requested array size exceeds VM limit"); 977 JvmtiExport::post_array_size_exhausted(); 978 THROW_OOP_0(Universe::out_of_memory_error_array_size()); 979 } 980 int size = objArrayOopDesc::object_size(length); 981 Klass* ak = array_klass(n, CHECK_NULL); 982 KlassHandle h_ak (THREAD, ak); 983 objArrayOop o = 984 (objArrayOop)CollectedHeap::array_allocate(h_ak, size, length, CHECK_NULL); 985 return o; 986 } 987 988 instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) { 989 if (TraceFinalizerRegistration) { 990 tty->print("Registered "); 991 i->print_value_on(tty); 992 tty->print_cr(" (" INTPTR_FORMAT ") as finalizable", p2i(i)); 993 } 994 instanceHandle h_i(THREAD, i); 995 // Pass the handle as argument, JavaCalls::call expects oop as jobjects 996 JavaValue result(T_VOID); 997 JavaCallArguments args(h_i); 998 methodHandle mh (THREAD, Universe::finalizer_register_method()); 999 JavaCalls::call(&result, mh, &args, CHECK_NULL); 1000 return h_i(); 1001 } 1002 1003 instanceOop InstanceKlass::allocate_instance(TRAPS) { 1004 bool has_finalizer_flag = has_finalizer(); // Query before possible GC 1005 int size = size_helper(); // Query before forming handle. 1006 1007 KlassHandle h_k(THREAD, this); 1008 1009 instanceOop i; 1010 1011 i = (instanceOop)CollectedHeap::obj_allocate(h_k, size, CHECK_NULL); 1012 if (has_finalizer_flag && !RegisterFinalizersAtInit) { 1013 i = register_finalizer(i, CHECK_NULL); 1014 } 1015 return i; 1016 } 1017 1018 void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) { 1019 if (is_interface() || is_abstract()) { 1020 ResourceMark rm(THREAD); 1021 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError() 1022 : vmSymbols::java_lang_InstantiationException(), external_name()); 1023 } 1024 if (this == SystemDictionary::Class_klass()) { 1025 ResourceMark rm(THREAD); 1026 THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError() 1027 : vmSymbols::java_lang_IllegalAccessException(), external_name()); 1028 } 1029 } 1030 1031 Klass* InstanceKlass::array_klass_impl(bool or_null, int n, TRAPS) { 1032 instanceKlassHandle this_k(THREAD, this); 1033 return array_klass_impl(this_k, or_null, n, THREAD); 1034 } 1035 1036 Klass* InstanceKlass::array_klass_impl(instanceKlassHandle this_k, bool or_null, int n, TRAPS) { 1037 if (this_k->array_klasses() == NULL) { 1038 if (or_null) return NULL; 1039 1040 ResourceMark rm; 1041 JavaThread *jt = (JavaThread *)THREAD; 1042 { 1043 // Atomic creation of array_klasses 1044 MutexLocker mc(Compile_lock, THREAD); // for vtables 1045 MutexLocker ma(MultiArray_lock, THREAD); 1046 1047 // Check if update has already taken place 1048 if (this_k->array_klasses() == NULL) { 1049 Klass* k = ObjArrayKlass::allocate_objArray_klass(this_k->class_loader_data(), 1, this_k, CHECK_NULL); 1050 this_k->set_array_klasses(k); 1051 } 1052 } 1053 } 1054 // _this will always be set at this point 1055 ObjArrayKlass* oak = (ObjArrayKlass*)this_k->array_klasses(); 1056 if (or_null) { 1057 return oak->array_klass_or_null(n); 1058 } 1059 return oak->array_klass(n, THREAD); 1060 } 1061 1062 Klass* InstanceKlass::array_klass_impl(bool or_null, TRAPS) { 1063 return array_klass_impl(or_null, 1, THREAD); 1064 } 1065 1066 void InstanceKlass::call_class_initializer(TRAPS) { 1067 instanceKlassHandle ik (THREAD, this); 1068 call_class_initializer_impl(ik, THREAD); 1069 } 1070 1071 static int call_class_initializer_impl_counter = 0; // for debugging 1072 1073 Method* InstanceKlass::class_initializer() { 1074 Method* clinit = find_method( 1075 vmSymbols::class_initializer_name(), vmSymbols::void_method_signature()); 1076 if (clinit != NULL && clinit->has_valid_initializer_flags()) { 1077 return clinit; 1078 } 1079 return NULL; 1080 } 1081 1082 void InstanceKlass::call_class_initializer_impl(instanceKlassHandle this_k, TRAPS) { 1083 if (ReplayCompiles && 1084 (ReplaySuppressInitializers == 1 || 1085 ReplaySuppressInitializers >= 2 && this_k->class_loader() != NULL)) { 1086 // Hide the existence of the initializer for the purpose of replaying the compile 1087 return; 1088 } 1089 1090 methodHandle h_method(THREAD, this_k->class_initializer()); 1091 assert(!this_k->is_initialized(), "we cannot initialize twice"); 1092 if (log_is_enabled(Info, classinit)) { 1093 ResourceMark rm; 1094 outputStream* log = LogHandle(classinit)::info_stream(); 1095 log->print("%d Initializing ", call_class_initializer_impl_counter++); 1096 this_k->name()->print_value_on(log); 1097 log->print_cr("%s (" INTPTR_FORMAT ")", h_method() == NULL ? "(no method)" : "", p2i(this_k())); 1098 } 1099 if (h_method() != NULL) { 1100 JavaCallArguments args; // No arguments 1101 JavaValue result(T_VOID); 1102 JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args) 1103 } 1104 } 1105 1106 1107 void InstanceKlass::mask_for(const methodHandle& method, int bci, 1108 InterpreterOopMap* entry_for) { 1109 // Dirty read, then double-check under a lock. 1110 if (_oop_map_cache == NULL) { 1111 // Otherwise, allocate a new one. 1112 MutexLocker x(OopMapCacheAlloc_lock); 1113 // First time use. Allocate a cache in C heap 1114 if (_oop_map_cache == NULL) { 1115 // Release stores from OopMapCache constructor before assignment 1116 // to _oop_map_cache. C++ compilers on ppc do not emit the 1117 // required memory barrier only because of the volatile 1118 // qualifier of _oop_map_cache. 1119 OrderAccess::release_store_ptr(&_oop_map_cache, new OopMapCache()); 1120 } 1121 } 1122 // _oop_map_cache is constant after init; lookup below does is own locking. 1123 _oop_map_cache->lookup(method, bci, entry_for); 1124 } 1125 1126 1127 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const { 1128 for (JavaFieldStream fs(this); !fs.done(); fs.next()) { 1129 Symbol* f_name = fs.name(); 1130 Symbol* f_sig = fs.signature(); 1131 if (f_name == name && f_sig == sig) { 1132 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index()); 1133 return true; 1134 } 1135 } 1136 return false; 1137 } 1138 1139 1140 Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const { 1141 const int n = local_interfaces()->length(); 1142 for (int i = 0; i < n; i++) { 1143 Klass* intf1 = local_interfaces()->at(i); 1144 assert(intf1->is_interface(), "just checking type"); 1145 // search for field in current interface 1146 if (InstanceKlass::cast(intf1)->find_local_field(name, sig, fd)) { 1147 assert(fd->is_static(), "interface field must be static"); 1148 return intf1; 1149 } 1150 // search for field in direct superinterfaces 1151 Klass* intf2 = InstanceKlass::cast(intf1)->find_interface_field(name, sig, fd); 1152 if (intf2 != NULL) return intf2; 1153 } 1154 // otherwise field lookup fails 1155 return NULL; 1156 } 1157 1158 1159 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const { 1160 // search order according to newest JVM spec (5.4.3.2, p.167). 1161 // 1) search for field in current klass 1162 if (find_local_field(name, sig, fd)) { 1163 return const_cast<InstanceKlass*>(this); 1164 } 1165 // 2) search for field recursively in direct superinterfaces 1166 { Klass* intf = find_interface_field(name, sig, fd); 1167 if (intf != NULL) return intf; 1168 } 1169 // 3) apply field lookup recursively if superclass exists 1170 { Klass* supr = super(); 1171 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, fd); 1172 } 1173 // 4) otherwise field lookup fails 1174 return NULL; 1175 } 1176 1177 1178 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const { 1179 // search order according to newest JVM spec (5.4.3.2, p.167). 1180 // 1) search for field in current klass 1181 if (find_local_field(name, sig, fd)) { 1182 if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this); 1183 } 1184 // 2) search for field recursively in direct superinterfaces 1185 if (is_static) { 1186 Klass* intf = find_interface_field(name, sig, fd); 1187 if (intf != NULL) return intf; 1188 } 1189 // 3) apply field lookup recursively if superclass exists 1190 { Klass* supr = super(); 1191 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, is_static, fd); 1192 } 1193 // 4) otherwise field lookup fails 1194 return NULL; 1195 } 1196 1197 1198 bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const { 1199 for (JavaFieldStream fs(this); !fs.done(); fs.next()) { 1200 if (fs.offset() == offset) { 1201 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index()); 1202 if (fd->is_static() == is_static) return true; 1203 } 1204 } 1205 return false; 1206 } 1207 1208 1209 bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const { 1210 Klass* klass = const_cast<InstanceKlass*>(this); 1211 while (klass != NULL) { 1212 if (InstanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) { 1213 return true; 1214 } 1215 klass = klass->super(); 1216 } 1217 return false; 1218 } 1219 1220 1221 void InstanceKlass::methods_do(void f(Method* method)) { 1222 // Methods aren't stable until they are loaded. This can be read outside 1223 // a lock through the ClassLoaderData for profiling 1224 if (!is_loaded()) { 1225 return; 1226 } 1227 1228 int len = methods()->length(); 1229 for (int index = 0; index < len; index++) { 1230 Method* m = methods()->at(index); 1231 assert(m->is_method(), "must be method"); 1232 f(m); 1233 } 1234 } 1235 1236 1237 void InstanceKlass::do_local_static_fields(FieldClosure* cl) { 1238 for (JavaFieldStream fs(this); !fs.done(); fs.next()) { 1239 if (fs.access_flags().is_static()) { 1240 fieldDescriptor& fd = fs.field_descriptor(); 1241 cl->do_field(&fd); 1242 } 1243 } 1244 } 1245 1246 1247 void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle mirror, TRAPS) { 1248 instanceKlassHandle h_this(THREAD, this); 1249 do_local_static_fields_impl(h_this, f, mirror, CHECK); 1250 } 1251 1252 1253 void InstanceKlass::do_local_static_fields_impl(instanceKlassHandle this_k, 1254 void f(fieldDescriptor* fd, Handle, TRAPS), Handle mirror, TRAPS) { 1255 for (JavaFieldStream fs(this_k()); !fs.done(); fs.next()) { 1256 if (fs.access_flags().is_static()) { 1257 fieldDescriptor& fd = fs.field_descriptor(); 1258 f(&fd, mirror, CHECK); 1259 } 1260 } 1261 } 1262 1263 1264 static int compare_fields_by_offset(int* a, int* b) { 1265 return a[0] - b[0]; 1266 } 1267 1268 void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) { 1269 InstanceKlass* super = superklass(); 1270 if (super != NULL) { 1271 super->do_nonstatic_fields(cl); 1272 } 1273 fieldDescriptor fd; 1274 int length = java_fields_count(); 1275 // In DebugInfo nonstatic fields are sorted by offset. 1276 int* fields_sorted = NEW_C_HEAP_ARRAY(int, 2*(length+1), mtClass); 1277 int j = 0; 1278 for (int i = 0; i < length; i += 1) { 1279 fd.reinitialize(this, i); 1280 if (!fd.is_static()) { 1281 fields_sorted[j + 0] = fd.offset(); 1282 fields_sorted[j + 1] = i; 1283 j += 2; 1284 } 1285 } 1286 if (j > 0) { 1287 length = j; 1288 // _sort_Fn is defined in growableArray.hpp. 1289 qsort(fields_sorted, length/2, 2*sizeof(int), (_sort_Fn)compare_fields_by_offset); 1290 for (int i = 0; i < length; i += 2) { 1291 fd.reinitialize(this, fields_sorted[i + 1]); 1292 assert(!fd.is_static() && fd.offset() == fields_sorted[i], "only nonstatic fields"); 1293 cl->do_field(&fd); 1294 } 1295 } 1296 FREE_C_HEAP_ARRAY(int, fields_sorted); 1297 } 1298 1299 1300 void InstanceKlass::array_klasses_do(void f(Klass* k, TRAPS), TRAPS) { 1301 if (array_klasses() != NULL) 1302 ArrayKlass::cast(array_klasses())->array_klasses_do(f, THREAD); 1303 } 1304 1305 void InstanceKlass::array_klasses_do(void f(Klass* k)) { 1306 if (array_klasses() != NULL) 1307 ArrayKlass::cast(array_klasses())->array_klasses_do(f); 1308 } 1309 1310 #ifdef ASSERT 1311 static int linear_search(const Array<Method*>* methods, 1312 const Symbol* name, 1313 const Symbol* signature) { 1314 const int len = methods->length(); 1315 for (int index = 0; index < len; index++) { 1316 const Method* const m = methods->at(index); 1317 assert(m->is_method(), "must be method"); 1318 if (m->signature() == signature && m->name() == name) { 1319 return index; 1320 } 1321 } 1322 return -1; 1323 } 1324 #endif 1325 1326 static int binary_search(const Array<Method*>* methods, const Symbol* name) { 1327 int len = methods->length(); 1328 // methods are sorted, so do binary search 1329 int l = 0; 1330 int h = len - 1; 1331 while (l <= h) { 1332 int mid = (l + h) >> 1; 1333 Method* m = methods->at(mid); 1334 assert(m->is_method(), "must be method"); 1335 int res = m->name()->fast_compare(name); 1336 if (res == 0) { 1337 return mid; 1338 } else if (res < 0) { 1339 l = mid + 1; 1340 } else { 1341 h = mid - 1; 1342 } 1343 } 1344 return -1; 1345 } 1346 1347 // find_method looks up the name/signature in the local methods array 1348 Method* InstanceKlass::find_method(const Symbol* name, 1349 const Symbol* signature) const { 1350 return find_method_impl(name, signature, find_overpass, find_static, find_private); 1351 } 1352 1353 Method* InstanceKlass::find_method_impl(const Symbol* name, 1354 const Symbol* signature, 1355 OverpassLookupMode overpass_mode, 1356 StaticLookupMode static_mode, 1357 PrivateLookupMode private_mode) const { 1358 return InstanceKlass::find_method_impl(methods(), 1359 name, 1360 signature, 1361 overpass_mode, 1362 static_mode, 1363 private_mode); 1364 } 1365 1366 // find_instance_method looks up the name/signature in the local methods array 1367 // and skips over static methods 1368 Method* InstanceKlass::find_instance_method(const Array<Method*>* methods, 1369 const Symbol* name, 1370 const Symbol* signature) { 1371 Method* const meth = InstanceKlass::find_method_impl(methods, 1372 name, 1373 signature, 1374 find_overpass, 1375 skip_static, 1376 find_private); 1377 assert(((meth == NULL) || !meth->is_static()), 1378 "find_instance_method should have skipped statics"); 1379 return meth; 1380 } 1381 1382 // find_instance_method looks up the name/signature in the local methods array 1383 // and skips over static methods 1384 Method* InstanceKlass::find_instance_method(const Symbol* name, const Symbol* signature) const { 1385 return InstanceKlass::find_instance_method(methods(), name, signature); 1386 } 1387 1388 // Find looks up the name/signature in the local methods array 1389 // and filters on the overpass, static and private flags 1390 // This returns the first one found 1391 // note that the local methods array can have up to one overpass, one static 1392 // and one instance (private or not) with the same name/signature 1393 Method* InstanceKlass::find_local_method(const Symbol* name, 1394 const Symbol* signature, 1395 OverpassLookupMode overpass_mode, 1396 StaticLookupMode static_mode, 1397 PrivateLookupMode private_mode) const { 1398 return InstanceKlass::find_method_impl(methods(), 1399 name, 1400 signature, 1401 overpass_mode, 1402 static_mode, 1403 private_mode); 1404 } 1405 1406 // Find looks up the name/signature in the local methods array 1407 // and filters on the overpass, static and private flags 1408 // This returns the first one found 1409 // note that the local methods array can have up to one overpass, one static 1410 // and one instance (private or not) with the same name/signature 1411 Method* InstanceKlass::find_local_method(const Array<Method*>* methods, 1412 const Symbol* name, 1413 const Symbol* signature, 1414 OverpassLookupMode overpass_mode, 1415 StaticLookupMode static_mode, 1416 PrivateLookupMode private_mode) { 1417 return InstanceKlass::find_method_impl(methods, 1418 name, 1419 signature, 1420 overpass_mode, 1421 static_mode, 1422 private_mode); 1423 } 1424 1425 Method* InstanceKlass::find_method(const Array<Method*>* methods, 1426 const Symbol* name, 1427 const Symbol* signature) { 1428 return InstanceKlass::find_method_impl(methods, 1429 name, 1430 signature, 1431 find_overpass, 1432 find_static, 1433 find_private); 1434 } 1435 1436 Method* InstanceKlass::find_method_impl(const Array<Method*>* methods, 1437 const Symbol* name, 1438 const Symbol* signature, 1439 OverpassLookupMode overpass_mode, 1440 StaticLookupMode static_mode, 1441 PrivateLookupMode private_mode) { 1442 int hit = find_method_index(methods, name, signature, overpass_mode, static_mode, private_mode); 1443 return hit >= 0 ? methods->at(hit): NULL; 1444 } 1445 1446 // true if method matches signature and conforms to skipping_X conditions. 1447 static bool method_matches(const Method* m, 1448 const Symbol* signature, 1449 bool skipping_overpass, 1450 bool skipping_static, 1451 bool skipping_private) { 1452 return ((m->signature() == signature) && 1453 (!skipping_overpass || !m->is_overpass()) && 1454 (!skipping_static || !m->is_static()) && 1455 (!skipping_private || !m->is_private())); 1456 } 1457 1458 // Used directly for default_methods to find the index into the 1459 // default_vtable_indices, and indirectly by find_method 1460 // find_method_index looks in the local methods array to return the index 1461 // of the matching name/signature. If, overpass methods are being ignored, 1462 // the search continues to find a potential non-overpass match. This capability 1463 // is important during method resolution to prefer a static method, for example, 1464 // over an overpass method. 1465 // There is the possibility in any _method's array to have the same name/signature 1466 // for a static method, an overpass method and a local instance method 1467 // To correctly catch a given method, the search criteria may need 1468 // to explicitly skip the other two. For local instance methods, it 1469 // is often necessary to skip private methods 1470 int InstanceKlass::find_method_index(const Array<Method*>* methods, 1471 const Symbol* name, 1472 const Symbol* signature, 1473 OverpassLookupMode overpass_mode, 1474 StaticLookupMode static_mode, 1475 PrivateLookupMode private_mode) { 1476 const bool skipping_overpass = (overpass_mode == skip_overpass); 1477 const bool skipping_static = (static_mode == skip_static); 1478 const bool skipping_private = (private_mode == skip_private); 1479 const int hit = binary_search(methods, name); 1480 if (hit != -1) { 1481 const Method* const m = methods->at(hit); 1482 1483 // Do linear search to find matching signature. First, quick check 1484 // for common case, ignoring overpasses if requested. 1485 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) { 1486 return hit; 1487 } 1488 1489 // search downwards through overloaded methods 1490 int i; 1491 for (i = hit - 1; i >= 0; --i) { 1492 const Method* const m = methods->at(i); 1493 assert(m->is_method(), "must be method"); 1494 if (m->name() != name) { 1495 break; 1496 } 1497 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) { 1498 return i; 1499 } 1500 } 1501 // search upwards 1502 for (i = hit + 1; i < methods->length(); ++i) { 1503 const Method* const m = methods->at(i); 1504 assert(m->is_method(), "must be method"); 1505 if (m->name() != name) { 1506 break; 1507 } 1508 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) { 1509 return i; 1510 } 1511 } 1512 // not found 1513 #ifdef ASSERT 1514 const int index = (skipping_overpass || skipping_static || skipping_private) ? -1 : 1515 linear_search(methods, name, signature); 1516 assert(-1 == index, "binary search should have found entry %d", index); 1517 #endif 1518 } 1519 return -1; 1520 } 1521 1522 int InstanceKlass::find_method_by_name(const Symbol* name, int* end) const { 1523 return find_method_by_name(methods(), name, end); 1524 } 1525 1526 int InstanceKlass::find_method_by_name(const Array<Method*>* methods, 1527 const Symbol* name, 1528 int* end_ptr) { 1529 assert(end_ptr != NULL, "just checking"); 1530 int start = binary_search(methods, name); 1531 int end = start + 1; 1532 if (start != -1) { 1533 while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start; 1534 while (end < methods->length() && (methods->at(end))->name() == name) ++end; 1535 *end_ptr = end; 1536 return start; 1537 } 1538 return -1; 1539 } 1540 1541 // uncached_lookup_method searches both the local class methods array and all 1542 // superclasses methods arrays, skipping any overpass methods in superclasses. 1543 Method* InstanceKlass::uncached_lookup_method(const Symbol* name, 1544 const Symbol* signature, 1545 OverpassLookupMode overpass_mode) const { 1546 OverpassLookupMode overpass_local_mode = overpass_mode; 1547 const Klass* klass = this; 1548 while (klass != NULL) { 1549 Method* const method = InstanceKlass::cast(klass)->find_method_impl(name, 1550 signature, 1551 overpass_local_mode, 1552 find_static, 1553 find_private); 1554 if (method != NULL) { 1555 return method; 1556 } 1557 klass = klass->super(); 1558 overpass_local_mode = skip_overpass; // Always ignore overpass methods in superclasses 1559 } 1560 return NULL; 1561 } 1562 1563 #ifdef ASSERT 1564 // search through class hierarchy and return true if this class or 1565 // one of the superclasses was redefined 1566 bool InstanceKlass::has_redefined_this_or_super() const { 1567 const Klass* klass = this; 1568 while (klass != NULL) { 1569 if (InstanceKlass::cast(klass)->has_been_redefined()) { 1570 return true; 1571 } 1572 klass = klass->super(); 1573 } 1574 return false; 1575 } 1576 #endif 1577 1578 // lookup a method in the default methods list then in all transitive interfaces 1579 // Do NOT return private or static methods 1580 Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name, 1581 Symbol* signature) const { 1582 Method* m = NULL; 1583 if (default_methods() != NULL) { 1584 m = find_method(default_methods(), name, signature); 1585 } 1586 // Look up interfaces 1587 if (m == NULL) { 1588 m = lookup_method_in_all_interfaces(name, signature, find_defaults); 1589 } 1590 return m; 1591 } 1592 1593 // lookup a method in all the interfaces that this class implements 1594 // Do NOT return private or static methods, new in JDK8 which are not externally visible 1595 // They should only be found in the initial InterfaceMethodRef 1596 Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name, 1597 Symbol* signature, 1598 DefaultsLookupMode defaults_mode) const { 1599 Array<Klass*>* all_ifs = transitive_interfaces(); 1600 int num_ifs = all_ifs->length(); 1601 InstanceKlass *ik = NULL; 1602 for (int i = 0; i < num_ifs; i++) { 1603 ik = InstanceKlass::cast(all_ifs->at(i)); 1604 Method* m = ik->lookup_method(name, signature); 1605 if (m != NULL && m->is_public() && !m->is_static() && 1606 ((defaults_mode != skip_defaults) || !m->is_default_method())) { 1607 return m; 1608 } 1609 } 1610 return NULL; 1611 } 1612 1613 /* jni_id_for_impl for jfieldIds only */ 1614 JNIid* InstanceKlass::jni_id_for_impl(instanceKlassHandle this_k, int offset) { 1615 MutexLocker ml(JfieldIdCreation_lock); 1616 // Retry lookup after we got the lock 1617 JNIid* probe = this_k->jni_ids() == NULL ? NULL : this_k->jni_ids()->find(offset); 1618 if (probe == NULL) { 1619 // Slow case, allocate new static field identifier 1620 probe = new JNIid(this_k(), offset, this_k->jni_ids()); 1621 this_k->set_jni_ids(probe); 1622 } 1623 return probe; 1624 } 1625 1626 1627 /* jni_id_for for jfieldIds only */ 1628 JNIid* InstanceKlass::jni_id_for(int offset) { 1629 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset); 1630 if (probe == NULL) { 1631 probe = jni_id_for_impl(this, offset); 1632 } 1633 return probe; 1634 } 1635 1636 u2 InstanceKlass::enclosing_method_data(int offset) const { 1637 const Array<jushort>* const inner_class_list = inner_classes(); 1638 if (inner_class_list == NULL) { 1639 return 0; 1640 } 1641 const int length = inner_class_list->length(); 1642 if (length % inner_class_next_offset == 0) { 1643 return 0; 1644 } 1645 const int index = length - enclosing_method_attribute_size; 1646 assert(offset < enclosing_method_attribute_size, "invalid offset"); 1647 return inner_class_list->at(index + offset); 1648 } 1649 1650 void InstanceKlass::set_enclosing_method_indices(u2 class_index, 1651 u2 method_index) { 1652 Array<jushort>* inner_class_list = inner_classes(); 1653 assert (inner_class_list != NULL, "_inner_classes list is not set up"); 1654 int length = inner_class_list->length(); 1655 if (length % inner_class_next_offset == enclosing_method_attribute_size) { 1656 int index = length - enclosing_method_attribute_size; 1657 inner_class_list->at_put( 1658 index + enclosing_method_class_index_offset, class_index); 1659 inner_class_list->at_put( 1660 index + enclosing_method_method_index_offset, method_index); 1661 } 1662 } 1663 1664 // Lookup or create a jmethodID. 1665 // This code is called by the VMThread and JavaThreads so the 1666 // locking has to be done very carefully to avoid deadlocks 1667 // and/or other cache consistency problems. 1668 // 1669 jmethodID InstanceKlass::get_jmethod_id(instanceKlassHandle ik_h, const methodHandle& method_h) { 1670 size_t idnum = (size_t)method_h->method_idnum(); 1671 jmethodID* jmeths = ik_h->methods_jmethod_ids_acquire(); 1672 size_t length = 0; 1673 jmethodID id = NULL; 1674 1675 // We use a double-check locking idiom here because this cache is 1676 // performance sensitive. In the normal system, this cache only 1677 // transitions from NULL to non-NULL which is safe because we use 1678 // release_set_methods_jmethod_ids() to advertise the new cache. 1679 // A partially constructed cache should never be seen by a racing 1680 // thread. We also use release_store_ptr() to save a new jmethodID 1681 // in the cache so a partially constructed jmethodID should never be 1682 // seen either. Cache reads of existing jmethodIDs proceed without a 1683 // lock, but cache writes of a new jmethodID requires uniqueness and 1684 // creation of the cache itself requires no leaks so a lock is 1685 // generally acquired in those two cases. 1686 // 1687 // If the RedefineClasses() API has been used, then this cache can 1688 // grow and we'll have transitions from non-NULL to bigger non-NULL. 1689 // Cache creation requires no leaks and we require safety between all 1690 // cache accesses and freeing of the old cache so a lock is generally 1691 // acquired when the RedefineClasses() API has been used. 1692 1693 if (jmeths != NULL) { 1694 // the cache already exists 1695 if (!ik_h->idnum_can_increment()) { 1696 // the cache can't grow so we can just get the current values 1697 get_jmethod_id_length_value(jmeths, idnum, &length, &id); 1698 } else { 1699 // cache can grow so we have to be more careful 1700 if (Threads::number_of_threads() == 0 || 1701 SafepointSynchronize::is_at_safepoint()) { 1702 // we're single threaded or at a safepoint - no locking needed 1703 get_jmethod_id_length_value(jmeths, idnum, &length, &id); 1704 } else { 1705 MutexLocker ml(JmethodIdCreation_lock); 1706 get_jmethod_id_length_value(jmeths, idnum, &length, &id); 1707 } 1708 } 1709 } 1710 // implied else: 1711 // we need to allocate a cache so default length and id values are good 1712 1713 if (jmeths == NULL || // no cache yet 1714 length <= idnum || // cache is too short 1715 id == NULL) { // cache doesn't contain entry 1716 1717 // This function can be called by the VMThread so we have to do all 1718 // things that might block on a safepoint before grabbing the lock. 1719 // Otherwise, we can deadlock with the VMThread or have a cache 1720 // consistency issue. These vars keep track of what we might have 1721 // to free after the lock is dropped. 1722 jmethodID to_dealloc_id = NULL; 1723 jmethodID* to_dealloc_jmeths = NULL; 1724 1725 // may not allocate new_jmeths or use it if we allocate it 1726 jmethodID* new_jmeths = NULL; 1727 if (length <= idnum) { 1728 // allocate a new cache that might be used 1729 size_t size = MAX2(idnum+1, (size_t)ik_h->idnum_allocated_count()); 1730 new_jmeths = NEW_C_HEAP_ARRAY(jmethodID, size+1, mtClass); 1731 memset(new_jmeths, 0, (size+1)*sizeof(jmethodID)); 1732 // cache size is stored in element[0], other elements offset by one 1733 new_jmeths[0] = (jmethodID)size; 1734 } 1735 1736 // allocate a new jmethodID that might be used 1737 jmethodID new_id = NULL; 1738 if (method_h->is_old() && !method_h->is_obsolete()) { 1739 // The method passed in is old (but not obsolete), we need to use the current version 1740 Method* current_method = ik_h->method_with_idnum((int)idnum); 1741 assert(current_method != NULL, "old and but not obsolete, so should exist"); 1742 new_id = Method::make_jmethod_id(ik_h->class_loader_data(), current_method); 1743 } else { 1744 // It is the current version of the method or an obsolete method, 1745 // use the version passed in 1746 new_id = Method::make_jmethod_id(ik_h->class_loader_data(), method_h()); 1747 } 1748 1749 if (Threads::number_of_threads() == 0 || 1750 SafepointSynchronize::is_at_safepoint()) { 1751 // we're single threaded or at a safepoint - no locking needed 1752 id = get_jmethod_id_fetch_or_update(ik_h, idnum, new_id, new_jmeths, 1753 &to_dealloc_id, &to_dealloc_jmeths); 1754 } else { 1755 MutexLocker ml(JmethodIdCreation_lock); 1756 id = get_jmethod_id_fetch_or_update(ik_h, idnum, new_id, new_jmeths, 1757 &to_dealloc_id, &to_dealloc_jmeths); 1758 } 1759 1760 // The lock has been dropped so we can free resources. 1761 // Free up either the old cache or the new cache if we allocated one. 1762 if (to_dealloc_jmeths != NULL) { 1763 FreeHeap(to_dealloc_jmeths); 1764 } 1765 // free up the new ID since it wasn't needed 1766 if (to_dealloc_id != NULL) { 1767 Method::destroy_jmethod_id(ik_h->class_loader_data(), to_dealloc_id); 1768 } 1769 } 1770 return id; 1771 } 1772 1773 // Figure out how many jmethodIDs haven't been allocated, and make 1774 // sure space for them is pre-allocated. This makes getting all 1775 // method ids much, much faster with classes with more than 8 1776 // methods, and has a *substantial* effect on performance with jvmti 1777 // code that loads all jmethodIDs for all classes. 1778 void InstanceKlass::ensure_space_for_methodids(int start_offset) { 1779 int new_jmeths = 0; 1780 int length = methods()->length(); 1781 for (int index = start_offset; index < length; index++) { 1782 Method* m = methods()->at(index); 1783 jmethodID id = m->find_jmethod_id_or_null(); 1784 if (id == NULL) { 1785 new_jmeths++; 1786 } 1787 } 1788 if (new_jmeths != 0) { 1789 Method::ensure_jmethod_ids(class_loader_data(), new_jmeths); 1790 } 1791 } 1792 1793 // Common code to fetch the jmethodID from the cache or update the 1794 // cache with the new jmethodID. This function should never do anything 1795 // that causes the caller to go to a safepoint or we can deadlock with 1796 // the VMThread or have cache consistency issues. 1797 // 1798 jmethodID InstanceKlass::get_jmethod_id_fetch_or_update( 1799 instanceKlassHandle ik_h, size_t idnum, jmethodID new_id, 1800 jmethodID* new_jmeths, jmethodID* to_dealloc_id_p, 1801 jmethodID** to_dealloc_jmeths_p) { 1802 assert(new_id != NULL, "sanity check"); 1803 assert(to_dealloc_id_p != NULL, "sanity check"); 1804 assert(to_dealloc_jmeths_p != NULL, "sanity check"); 1805 assert(Threads::number_of_threads() == 0 || 1806 SafepointSynchronize::is_at_safepoint() || 1807 JmethodIdCreation_lock->owned_by_self(), "sanity check"); 1808 1809 // reacquire the cache - we are locked, single threaded or at a safepoint 1810 jmethodID* jmeths = ik_h->methods_jmethod_ids_acquire(); 1811 jmethodID id = NULL; 1812 size_t length = 0; 1813 1814 if (jmeths == NULL || // no cache yet 1815 (length = (size_t)jmeths[0]) <= idnum) { // cache is too short 1816 if (jmeths != NULL) { 1817 // copy any existing entries from the old cache 1818 for (size_t index = 0; index < length; index++) { 1819 new_jmeths[index+1] = jmeths[index+1]; 1820 } 1821 *to_dealloc_jmeths_p = jmeths; // save old cache for later delete 1822 } 1823 ik_h->release_set_methods_jmethod_ids(jmeths = new_jmeths); 1824 } else { 1825 // fetch jmethodID (if any) from the existing cache 1826 id = jmeths[idnum+1]; 1827 *to_dealloc_jmeths_p = new_jmeths; // save new cache for later delete 1828 } 1829 if (id == NULL) { 1830 // No matching jmethodID in the existing cache or we have a new 1831 // cache or we just grew the cache. This cache write is done here 1832 // by the first thread to win the foot race because a jmethodID 1833 // needs to be unique once it is generally available. 1834 id = new_id; 1835 1836 // The jmethodID cache can be read while unlocked so we have to 1837 // make sure the new jmethodID is complete before installing it 1838 // in the cache. 1839 OrderAccess::release_store_ptr(&jmeths[idnum+1], id); 1840 } else { 1841 *to_dealloc_id_p = new_id; // save new id for later delete 1842 } 1843 return id; 1844 } 1845 1846 1847 // Common code to get the jmethodID cache length and the jmethodID 1848 // value at index idnum if there is one. 1849 // 1850 void InstanceKlass::get_jmethod_id_length_value(jmethodID* cache, 1851 size_t idnum, size_t *length_p, jmethodID* id_p) { 1852 assert(cache != NULL, "sanity check"); 1853 assert(length_p != NULL, "sanity check"); 1854 assert(id_p != NULL, "sanity check"); 1855 1856 // cache size is stored in element[0], other elements offset by one 1857 *length_p = (size_t)cache[0]; 1858 if (*length_p <= idnum) { // cache is too short 1859 *id_p = NULL; 1860 } else { 1861 *id_p = cache[idnum+1]; // fetch jmethodID (if any) 1862 } 1863 } 1864 1865 1866 // Lookup a jmethodID, NULL if not found. Do no blocking, no allocations, no handles 1867 jmethodID InstanceKlass::jmethod_id_or_null(Method* method) { 1868 size_t idnum = (size_t)method->method_idnum(); 1869 jmethodID* jmeths = methods_jmethod_ids_acquire(); 1870 size_t length; // length assigned as debugging crumb 1871 jmethodID id = NULL; 1872 if (jmeths != NULL && // If there is a cache 1873 (length = (size_t)jmeths[0]) > idnum) { // and if it is long enough, 1874 id = jmeths[idnum+1]; // Look up the id (may be NULL) 1875 } 1876 return id; 1877 } 1878 1879 inline DependencyContext InstanceKlass::dependencies() { 1880 DependencyContext dep_context(&_dep_context); 1881 return dep_context; 1882 } 1883 1884 int InstanceKlass::mark_dependent_nmethods(DepChange& changes) { 1885 return dependencies().mark_dependent_nmethods(changes); 1886 } 1887 1888 void InstanceKlass::add_dependent_nmethod(nmethod* nm) { 1889 dependencies().add_dependent_nmethod(nm); 1890 } 1891 1892 void InstanceKlass::remove_dependent_nmethod(nmethod* nm, bool delete_immediately) { 1893 dependencies().remove_dependent_nmethod(nm, delete_immediately); 1894 } 1895 1896 #ifndef PRODUCT 1897 void InstanceKlass::print_dependent_nmethods(bool verbose) { 1898 dependencies().print_dependent_nmethods(verbose); 1899 } 1900 1901 bool InstanceKlass::is_dependent_nmethod(nmethod* nm) { 1902 return dependencies().is_dependent_nmethod(nm); 1903 } 1904 #endif //PRODUCT 1905 1906 void InstanceKlass::clean_weak_instanceklass_links(BoolObjectClosure* is_alive) { 1907 clean_implementors_list(is_alive); 1908 clean_method_data(is_alive); 1909 1910 // Since GC iterates InstanceKlasses sequentially, it is safe to remove stale entries here. 1911 DependencyContext dep_context(&_dep_context); 1912 dep_context.expunge_stale_entries(); 1913 } 1914 1915 void InstanceKlass::clean_implementors_list(BoolObjectClosure* is_alive) { 1916 assert(class_loader_data()->is_alive(is_alive), "this klass should be live"); 1917 if (is_interface()) { 1918 if (ClassUnloading) { 1919 Klass* impl = implementor(); 1920 if (impl != NULL) { 1921 if (!impl->is_loader_alive(is_alive)) { 1922 // remove this guy 1923 Klass** klass = adr_implementor(); 1924 assert(klass != NULL, "null klass"); 1925 if (klass != NULL) { 1926 *klass = NULL; 1927 } 1928 } 1929 } 1930 } 1931 } 1932 } 1933 1934 void InstanceKlass::clean_method_data(BoolObjectClosure* is_alive) { 1935 for (int m = 0; m < methods()->length(); m++) { 1936 MethodData* mdo = methods()->at(m)->method_data(); 1937 if (mdo != NULL) { 1938 mdo->clean_method_data(is_alive); 1939 } 1940 } 1941 } 1942 1943 1944 static void remove_unshareable_in_class(Klass* k) { 1945 // remove klass's unshareable info 1946 k->remove_unshareable_info(); 1947 } 1948 1949 void InstanceKlass::remove_unshareable_info() { 1950 Klass::remove_unshareable_info(); 1951 // Unlink the class 1952 if (is_linked()) { 1953 unlink_class(); 1954 } 1955 init_implementor(); 1956 1957 constants()->remove_unshareable_info(); 1958 1959 assert(_dep_context == DependencyContext::EMPTY, "dependency context is not shareable"); 1960 1961 for (int i = 0; i < methods()->length(); i++) { 1962 Method* m = methods()->at(i); 1963 m->remove_unshareable_info(); 1964 } 1965 1966 // do array classes also. 1967 array_klasses_do(remove_unshareable_in_class); 1968 } 1969 1970 static void restore_unshareable_in_class(Klass* k, TRAPS) { 1971 // Array classes have null protection domain. 1972 // --> see ArrayKlass::complete_create_array_klass() 1973 k->restore_unshareable_info(ClassLoaderData::the_null_class_loader_data(), Handle(), CHECK); 1974 } 1975 1976 void InstanceKlass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain, TRAPS) { 1977 Klass::restore_unshareable_info(loader_data, protection_domain, CHECK); 1978 instanceKlassHandle ik(THREAD, this); 1979 1980 Array<Method*>* methods = ik->methods(); 1981 int num_methods = methods->length(); 1982 for (int index2 = 0; index2 < num_methods; ++index2) { 1983 methodHandle m(THREAD, methods->at(index2)); 1984 m->restore_unshareable_info(CHECK); 1985 } 1986 if (JvmtiExport::has_redefined_a_class()) { 1987 // Reinitialize vtable because RedefineClasses may have changed some 1988 // entries in this vtable for super classes so the CDS vtable might 1989 // point to old or obsolete entries. RedefineClasses doesn't fix up 1990 // vtables in the shared system dictionary, only the main one. 1991 // It also redefines the itable too so fix that too. 1992 ResourceMark rm(THREAD); 1993 ik->vtable()->initialize_vtable(false, CHECK); 1994 ik->itable()->initialize_itable(false, CHECK); 1995 } 1996 1997 // restore constant pool resolved references 1998 ik->constants()->restore_unshareable_info(CHECK); 1999 2000 ik->array_klasses_do(restore_unshareable_in_class, CHECK); 2001 } 2002 2003 // returns true IFF is_in_error_state() has been changed as a result of this call. 2004 bool InstanceKlass::check_sharing_error_state() { 2005 assert(DumpSharedSpaces, "should only be called during dumping"); 2006 bool old_state = is_in_error_state(); 2007 2008 if (!is_in_error_state()) { 2009 bool bad = false; 2010 for (InstanceKlass* sup = java_super(); sup; sup = sup->java_super()) { 2011 if (sup->is_in_error_state()) { 2012 bad = true; 2013 break; 2014 } 2015 } 2016 if (!bad) { 2017 Array<Klass*>* interfaces = transitive_interfaces(); 2018 for (int i = 0; i < interfaces->length(); i++) { 2019 Klass* iface = interfaces->at(i); 2020 if (InstanceKlass::cast(iface)->is_in_error_state()) { 2021 bad = true; 2022 break; 2023 } 2024 } 2025 } 2026 2027 if (bad) { 2028 set_in_error_state(); 2029 } 2030 } 2031 2032 return (old_state != is_in_error_state()); 2033 } 2034 2035 static void clear_all_breakpoints(Method* m) { 2036 m->clear_all_breakpoints(); 2037 } 2038 2039 2040 void InstanceKlass::notify_unload_class(InstanceKlass* ik) { 2041 // notify the debugger 2042 if (JvmtiExport::should_post_class_unload()) { 2043 JvmtiExport::post_class_unload(ik); 2044 } 2045 2046 // notify ClassLoadingService of class unload 2047 ClassLoadingService::notify_class_unloaded(ik); 2048 } 2049 2050 void InstanceKlass::release_C_heap_structures(InstanceKlass* ik) { 2051 // Clean up C heap 2052 ik->release_C_heap_structures(); 2053 ik->constants()->release_C_heap_structures(); 2054 } 2055 2056 void InstanceKlass::release_C_heap_structures() { 2057 2058 // Can't release the constant pool here because the constant pool can be 2059 // deallocated separately from the InstanceKlass for default methods and 2060 // redefine classes. 2061 2062 // Deallocate oop map cache 2063 if (_oop_map_cache != NULL) { 2064 delete _oop_map_cache; 2065 _oop_map_cache = NULL; 2066 } 2067 2068 // Deallocate JNI identifiers for jfieldIDs 2069 JNIid::deallocate(jni_ids()); 2070 set_jni_ids(NULL); 2071 2072 jmethodID* jmeths = methods_jmethod_ids_acquire(); 2073 if (jmeths != (jmethodID*)NULL) { 2074 release_set_methods_jmethod_ids(NULL); 2075 FreeHeap(jmeths); 2076 } 2077 2078 // Deallocate MemberNameTable 2079 { 2080 Mutex* lock_or_null = SafepointSynchronize::is_at_safepoint() ? NULL : MemberNameTable_lock; 2081 MutexLockerEx ml(lock_or_null, Mutex::_no_safepoint_check_flag); 2082 MemberNameTable* mnt = member_names(); 2083 if (mnt != NULL) { 2084 delete mnt; 2085 set_member_names(NULL); 2086 } 2087 } 2088 2089 // Release dependencies. 2090 // It is desirable to use DC::remove_all_dependents() here, but, unfortunately, 2091 // it is not safe (see JDK-8143408). The problem is that the klass dependency 2092 // context can contain live dependencies, since there's a race between nmethod & 2093 // klass unloading. If the klass is dead when nmethod unloading happens, relevant 2094 // dependencies aren't removed from the context associated with the class (see 2095 // nmethod::flush_dependencies). It ends up during klass unloading as seemingly 2096 // live dependencies pointing to unloaded nmethods and causes a crash in 2097 // DC::remove_all_dependents() when it touches unloaded nmethod. 2098 dependencies().wipe(); 2099 2100 // Deallocate breakpoint records 2101 if (breakpoints() != 0x0) { 2102 methods_do(clear_all_breakpoints); 2103 assert(breakpoints() == 0x0, "should have cleared breakpoints"); 2104 } 2105 2106 // deallocate the cached class file 2107 if (_cached_class_file != NULL) { 2108 os::free(_cached_class_file); 2109 _cached_class_file = NULL; 2110 } 2111 2112 // Decrement symbol reference counts associated with the unloaded class. 2113 if (_name != NULL) _name->decrement_refcount(); 2114 // unreference array name derived from this class name (arrays of an unloaded 2115 // class can't be referenced anymore). 2116 if (_array_name != NULL) _array_name->decrement_refcount(); 2117 if (_source_debug_extension != NULL) FREE_C_HEAP_ARRAY(char, _source_debug_extension); 2118 2119 assert(_total_instanceKlass_count >= 1, "Sanity check"); 2120 Atomic::dec(&_total_instanceKlass_count); 2121 } 2122 2123 void InstanceKlass::set_source_debug_extension(const char* array, int length) { 2124 if (array == NULL) { 2125 _source_debug_extension = NULL; 2126 } else { 2127 // Adding one to the attribute length in order to store a null terminator 2128 // character could cause an overflow because the attribute length is 2129 // already coded with an u4 in the classfile, but in practice, it's 2130 // unlikely to happen. 2131 assert((length+1) > length, "Overflow checking"); 2132 char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass); 2133 for (int i = 0; i < length; i++) { 2134 sde[i] = array[i]; 2135 } 2136 sde[length] = '\0'; 2137 _source_debug_extension = sde; 2138 } 2139 } 2140 2141 address InstanceKlass::static_field_addr(int offset) { 2142 return (address)(offset + InstanceMirrorKlass::offset_of_static_fields() + cast_from_oop<intptr_t>(java_mirror())); 2143 } 2144 2145 2146 const char* InstanceKlass::signature_name() const { 2147 int hash_len = 0; 2148 char hash_buf[40]; 2149 2150 // If this is an anonymous class, append a hash to make the name unique 2151 if (is_anonymous()) { 2152 intptr_t hash = (java_mirror() != NULL) ? java_mirror()->identity_hash() : 0; 2153 jio_snprintf(hash_buf, sizeof(hash_buf), "/" UINTX_FORMAT, (uintx)hash); 2154 hash_len = (int)strlen(hash_buf); 2155 } 2156 2157 // Get the internal name as a c string 2158 const char* src = (const char*) (name()->as_C_string()); 2159 const int src_length = (int)strlen(src); 2160 2161 char* dest = NEW_RESOURCE_ARRAY(char, src_length + hash_len + 3); 2162 2163 // Add L as type indicator 2164 int dest_index = 0; 2165 dest[dest_index++] = 'L'; 2166 2167 // Add the actual class name 2168 for (int src_index = 0; src_index < src_length; ) { 2169 dest[dest_index++] = src[src_index++]; 2170 } 2171 2172 // If we have a hash, append it 2173 for (int hash_index = 0; hash_index < hash_len; ) { 2174 dest[dest_index++] = hash_buf[hash_index++]; 2175 } 2176 2177 // Add the semicolon and the NULL 2178 dest[dest_index++] = ';'; 2179 dest[dest_index] = '\0'; 2180 return dest; 2181 } 2182 2183 // different verisons of is_same_class_package 2184 bool InstanceKlass::is_same_class_package(const Klass* class2) const { 2185 const Klass* const class1 = (const Klass* const)this; 2186 oop classloader1 = InstanceKlass::cast(class1)->class_loader(); 2187 const Symbol* const classname1 = class1->name(); 2188 2189 if (class2->is_objArray_klass()) { 2190 class2 = ObjArrayKlass::cast(class2)->bottom_klass(); 2191 } 2192 oop classloader2; 2193 if (class2->is_instance_klass()) { 2194 classloader2 = InstanceKlass::cast(class2)->class_loader(); 2195 } else { 2196 assert(class2->is_typeArray_klass(), "should be type array"); 2197 classloader2 = NULL; 2198 } 2199 const Symbol* classname2 = class2->name(); 2200 2201 return InstanceKlass::is_same_class_package(classloader1, classname1, 2202 classloader2, classname2); 2203 } 2204 2205 bool InstanceKlass::is_same_class_package(oop other_class_loader, 2206 const Symbol* other_class_name) const { 2207 oop this_class_loader = class_loader(); 2208 const Symbol* const this_class_name = name(); 2209 2210 return InstanceKlass::is_same_class_package(this_class_loader, 2211 this_class_name, 2212 other_class_loader, 2213 other_class_name); 2214 } 2215 2216 // return true if two classes are in the same package, classloader 2217 // and classname information is enough to determine a class's package 2218 bool InstanceKlass::is_same_class_package(oop class_loader1, const Symbol* class_name1, 2219 oop class_loader2, const Symbol* class_name2) { 2220 if (class_loader1 != class_loader2) { 2221 return false; 2222 } else if (class_name1 == class_name2) { 2223 return true; // skip painful bytewise comparison 2224 } else { 2225 ResourceMark rm; 2226 2227 // The Symbol*'s are in UTF8 encoding. Since we only need to check explicitly 2228 // for ASCII characters ('/', 'L', '['), we can keep them in UTF8 encoding. 2229 // Otherwise, we just compare jbyte values between the strings. 2230 const jbyte *name1 = class_name1->base(); 2231 const jbyte *name2 = class_name2->base(); 2232 2233 const jbyte *last_slash1 = UTF8::strrchr(name1, class_name1->utf8_length(), '/'); 2234 const jbyte *last_slash2 = UTF8::strrchr(name2, class_name2->utf8_length(), '/'); 2235 2236 if ((last_slash1 == NULL) || (last_slash2 == NULL)) { 2237 // One of the two doesn't have a package. Only return true 2238 // if the other one also doesn't have a package. 2239 return last_slash1 == last_slash2; 2240 } else { 2241 // Skip over '['s 2242 if (*name1 == '[') { 2243 do { 2244 name1++; 2245 } while (*name1 == '['); 2246 if (*name1 != 'L') { 2247 // Something is terribly wrong. Shouldn't be here. 2248 return false; 2249 } 2250 } 2251 if (*name2 == '[') { 2252 do { 2253 name2++; 2254 } while (*name2 == '['); 2255 if (*name2 != 'L') { 2256 // Something is terribly wrong. Shouldn't be here. 2257 return false; 2258 } 2259 } 2260 2261 // Check that package part is identical 2262 int length1 = last_slash1 - name1; 2263 int length2 = last_slash2 - name2; 2264 2265 return UTF8::equal(name1, length1, name2, length2); 2266 } 2267 } 2268 } 2269 2270 // Returns true iff super_method can be overridden by a method in targetclassname 2271 // See JSL 3rd edition 8.4.6.1 2272 // Assumes name-signature match 2273 // "this" is InstanceKlass of super_method which must exist 2274 // note that the InstanceKlass of the method in the targetclassname has not always been created yet 2275 bool InstanceKlass::is_override(const methodHandle& super_method, Handle targetclassloader, Symbol* targetclassname, TRAPS) { 2276 // Private methods can not be overridden 2277 if (super_method->is_private()) { 2278 return false; 2279 } 2280 // If super method is accessible, then override 2281 if ((super_method->is_protected()) || 2282 (super_method->is_public())) { 2283 return true; 2284 } 2285 // Package-private methods are not inherited outside of package 2286 assert(super_method->is_package_private(), "must be package private"); 2287 return(is_same_class_package(targetclassloader(), targetclassname)); 2288 } 2289 2290 /* defined for now in jvm.cpp, for historical reasons *-- 2291 Klass* InstanceKlass::compute_enclosing_class_impl(instanceKlassHandle self, 2292 Symbol*& simple_name_result, TRAPS) { 2293 ... 2294 } 2295 */ 2296 2297 // tell if two classes have the same enclosing class (at package level) 2298 bool InstanceKlass::is_same_package_member_impl(const InstanceKlass* class1, 2299 const Klass* class2, 2300 TRAPS) { 2301 if (class2 == class1) return true; 2302 if (!class2->is_instance_klass()) return false; 2303 2304 // must be in same package before we try anything else 2305 if (!class1->is_same_class_package(class2->class_loader(), class2->name())) 2306 return false; 2307 2308 // As long as there is an outer1.getEnclosingClass, 2309 // shift the search outward. 2310 const InstanceKlass* outer1 = class1; 2311 for (;;) { 2312 // As we walk along, look for equalities between outer1 and class2. 2313 // Eventually, the walks will terminate as outer1 stops 2314 // at the top-level class around the original class. 2315 bool ignore_inner_is_member; 2316 const Klass* next = outer1->compute_enclosing_class(&ignore_inner_is_member, 2317 CHECK_false); 2318 if (next == NULL) break; 2319 if (next == class2) return true; 2320 outer1 = InstanceKlass::cast(next); 2321 } 2322 2323 // Now do the same for class2. 2324 const InstanceKlass* outer2 = InstanceKlass::cast(class2); 2325 for (;;) { 2326 bool ignore_inner_is_member; 2327 Klass* next = outer2->compute_enclosing_class(&ignore_inner_is_member, 2328 CHECK_false); 2329 if (next == NULL) break; 2330 // Might as well check the new outer against all available values. 2331 if (next == class1) return true; 2332 if (next == outer1) return true; 2333 outer2 = InstanceKlass::cast(next); 2334 } 2335 2336 // If by this point we have not found an equality between the 2337 // two classes, we know they are in separate package members. 2338 return false; 2339 } 2340 2341 bool InstanceKlass::find_inner_classes_attr(instanceKlassHandle k, int* ooff, int* noff, TRAPS) { 2342 constantPoolHandle i_cp(THREAD, k->constants()); 2343 for (InnerClassesIterator iter(k); !iter.done(); iter.next()) { 2344 int ioff = iter.inner_class_info_index(); 2345 if (ioff != 0) { 2346 // Check to see if the name matches the class we're looking for 2347 // before attempting to find the class. 2348 if (i_cp->klass_name_at_matches(k, ioff)) { 2349 Klass* inner_klass = i_cp->klass_at(ioff, CHECK_false); 2350 if (k() == inner_klass) { 2351 *ooff = iter.outer_class_info_index(); 2352 *noff = iter.inner_name_index(); 2353 return true; 2354 } 2355 } 2356 } 2357 } 2358 return false; 2359 } 2360 2361 InstanceKlass* InstanceKlass::compute_enclosing_class_impl(const InstanceKlass* k, 2362 bool* inner_is_member, 2363 TRAPS) { 2364 InstanceKlass* outer_klass = NULL; 2365 *inner_is_member = false; 2366 int ooff = 0, noff = 0; 2367 if (find_inner_classes_attr(k, &ooff, &noff, THREAD)) { 2368 constantPoolHandle i_cp(THREAD, k->constants()); 2369 if (ooff != 0) { 2370 Klass* ok = i_cp->klass_at(ooff, CHECK_NULL); 2371 outer_klass = InstanceKlass::cast(ok); 2372 *inner_is_member = true; 2373 } 2374 if (NULL == outer_klass) { 2375 // It may be anonymous; try for that. 2376 int encl_method_class_idx = k->enclosing_method_class_index(); 2377 if (encl_method_class_idx != 0) { 2378 Klass* ok = i_cp->klass_at(encl_method_class_idx, CHECK_NULL); 2379 outer_klass = InstanceKlass::cast(ok); 2380 *inner_is_member = false; 2381 } 2382 } 2383 } 2384 2385 // If no inner class attribute found for this class. 2386 if (NULL == outer_klass) return NULL; 2387 2388 // Throws an exception if outer klass has not declared k as an inner klass 2389 // We need evidence that each klass knows about the other, or else 2390 // the system could allow a spoof of an inner class to gain access rights. 2391 Reflection::check_for_inner_class(outer_klass, k, *inner_is_member, CHECK_NULL); 2392 return outer_klass; 2393 } 2394 2395 jint InstanceKlass::compute_modifier_flags(TRAPS) const { 2396 jint access = access_flags().as_int(); 2397 2398 // But check if it happens to be member class. 2399 instanceKlassHandle ik(THREAD, this); 2400 InnerClassesIterator iter(ik); 2401 for (; !iter.done(); iter.next()) { 2402 int ioff = iter.inner_class_info_index(); 2403 // Inner class attribute can be zero, skip it. 2404 // Strange but true: JVM spec. allows null inner class refs. 2405 if (ioff == 0) continue; 2406 2407 // only look at classes that are already loaded 2408 // since we are looking for the flags for our self. 2409 Symbol* inner_name = ik->constants()->klass_name_at(ioff); 2410 if ((ik->name() == inner_name)) { 2411 // This is really a member class. 2412 access = iter.inner_access_flags(); 2413 break; 2414 } 2415 } 2416 // Remember to strip ACC_SUPER bit 2417 return (access & (~JVM_ACC_SUPER)) & JVM_ACC_WRITTEN_FLAGS; 2418 } 2419 2420 jint InstanceKlass::jvmti_class_status() const { 2421 jint result = 0; 2422 2423 if (is_linked()) { 2424 result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED; 2425 } 2426 2427 if (is_initialized()) { 2428 assert(is_linked(), "Class status is not consistent"); 2429 result |= JVMTI_CLASS_STATUS_INITIALIZED; 2430 } 2431 if (is_in_error_state()) { 2432 result |= JVMTI_CLASS_STATUS_ERROR; 2433 } 2434 return result; 2435 } 2436 2437 Method* InstanceKlass::method_at_itable(Klass* holder, int index, TRAPS) { 2438 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable(); 2439 int method_table_offset_in_words = ioe->offset()/wordSize; 2440 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words()) 2441 / itableOffsetEntry::size(); 2442 2443 for (int cnt = 0 ; ; cnt ++, ioe ++) { 2444 // If the interface isn't implemented by the receiver class, 2445 // the VM should throw IncompatibleClassChangeError. 2446 if (cnt >= nof_interfaces) { 2447 THROW_NULL(vmSymbols::java_lang_IncompatibleClassChangeError()); 2448 } 2449 2450 Klass* ik = ioe->interface_klass(); 2451 if (ik == holder) break; 2452 } 2453 2454 itableMethodEntry* ime = ioe->first_method_entry(this); 2455 Method* m = ime[index].method(); 2456 if (m == NULL) { 2457 THROW_NULL(vmSymbols::java_lang_AbstractMethodError()); 2458 } 2459 return m; 2460 } 2461 2462 2463 #if INCLUDE_JVMTI 2464 // update default_methods for redefineclasses for methods that are 2465 // not yet in the vtable due to concurrent subclass define and superinterface 2466 // redefinition 2467 // Note: those in the vtable, should have been updated via adjust_method_entries 2468 void InstanceKlass::adjust_default_methods(InstanceKlass* holder, bool* trace_name_printed) { 2469 // search the default_methods for uses of either obsolete or EMCP methods 2470 if (default_methods() != NULL) { 2471 for (int index = 0; index < default_methods()->length(); index ++) { 2472 Method* old_method = default_methods()->at(index); 2473 if (old_method == NULL || old_method->method_holder() != holder || !old_method->is_old()) { 2474 continue; // skip uninteresting entries 2475 } 2476 assert(!old_method->is_deleted(), "default methods may not be deleted"); 2477 2478 Method* new_method = holder->method_with_idnum(old_method->orig_method_idnum()); 2479 2480 assert(new_method != NULL, "method_with_idnum() should not be NULL"); 2481 assert(old_method != new_method, "sanity check"); 2482 2483 default_methods()->at_put(index, new_method); 2484 if (RC_TRACE_IN_RANGE(0x00100000, 0x00400000)) { 2485 if (!(*trace_name_printed)) { 2486 // RC_TRACE_MESG macro has an embedded ResourceMark 2487 RC_TRACE_MESG(("adjust: klassname=%s default methods from name=%s", 2488 external_name(), 2489 old_method->method_holder()->external_name())); 2490 *trace_name_printed = true; 2491 } 2492 RC_TRACE(0x00100000, ("default method update: %s(%s) ", 2493 new_method->name()->as_C_string(), 2494 new_method->signature()->as_C_string())); 2495 } 2496 } 2497 } 2498 } 2499 #endif // INCLUDE_JVMTI 2500 2501 // On-stack replacement stuff 2502 void InstanceKlass::add_osr_nmethod(nmethod* n) { 2503 // only one compilation can be active 2504 { 2505 // This is a short non-blocking critical region, so the no safepoint check is ok. 2506 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag); 2507 assert(n->is_osr_method(), "wrong kind of nmethod"); 2508 n->set_osr_link(osr_nmethods_head()); 2509 set_osr_nmethods_head(n); 2510 // Raise the highest osr level if necessary 2511 if (TieredCompilation) { 2512 Method* m = n->method(); 2513 m->set_highest_osr_comp_level(MAX2(m->highest_osr_comp_level(), n->comp_level())); 2514 } 2515 } 2516 2517 // Get rid of the osr methods for the same bci that have lower levels. 2518 if (TieredCompilation) { 2519 for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) { 2520 nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true); 2521 if (inv != NULL && inv->is_in_use()) { 2522 inv->make_not_entrant(); 2523 } 2524 } 2525 } 2526 } 2527 2528 2529 void InstanceKlass::remove_osr_nmethod(nmethod* n) { 2530 // This is a short non-blocking critical region, so the no safepoint check is ok. 2531 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag); 2532 assert(n->is_osr_method(), "wrong kind of nmethod"); 2533 nmethod* last = NULL; 2534 nmethod* cur = osr_nmethods_head(); 2535 int max_level = CompLevel_none; // Find the max comp level excluding n 2536 Method* m = n->method(); 2537 // Search for match 2538 while(cur != NULL && cur != n) { 2539 if (TieredCompilation && m == cur->method()) { 2540 // Find max level before n 2541 max_level = MAX2(max_level, cur->comp_level()); 2542 } 2543 last = cur; 2544 cur = cur->osr_link(); 2545 } 2546 nmethod* next = NULL; 2547 if (cur == n) { 2548 next = cur->osr_link(); 2549 if (last == NULL) { 2550 // Remove first element 2551 set_osr_nmethods_head(next); 2552 } else { 2553 last->set_osr_link(next); 2554 } 2555 } 2556 n->set_osr_link(NULL); 2557 if (TieredCompilation) { 2558 cur = next; 2559 while (cur != NULL) { 2560 // Find max level after n 2561 if (m == cur->method()) { 2562 max_level = MAX2(max_level, cur->comp_level()); 2563 } 2564 cur = cur->osr_link(); 2565 } 2566 m->set_highest_osr_comp_level(max_level); 2567 } 2568 } 2569 2570 int InstanceKlass::mark_osr_nmethods(const Method* m) { 2571 // This is a short non-blocking critical region, so the no safepoint check is ok. 2572 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag); 2573 nmethod* osr = osr_nmethods_head(); 2574 int found = 0; 2575 while (osr != NULL) { 2576 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain"); 2577 if (osr->method() == m) { 2578 osr->mark_for_deoptimization(); 2579 found++; 2580 } 2581 osr = osr->osr_link(); 2582 } 2583 return found; 2584 } 2585 2586 nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const { 2587 // This is a short non-blocking critical region, so the no safepoint check is ok. 2588 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag); 2589 nmethod* osr = osr_nmethods_head(); 2590 nmethod* best = NULL; 2591 while (osr != NULL) { 2592 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain"); 2593 // There can be a time when a c1 osr method exists but we are waiting 2594 // for a c2 version. When c2 completes its osr nmethod we will trash 2595 // the c1 version and only be able to find the c2 version. However 2596 // while we overflow in the c1 code at back branches we don't want to 2597 // try and switch to the same code as we are already running 2598 2599 if (osr->method() == m && 2600 (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) { 2601 if (match_level) { 2602 if (osr->comp_level() == comp_level) { 2603 // Found a match - return it. 2604 return osr; 2605 } 2606 } else { 2607 if (best == NULL || (osr->comp_level() > best->comp_level())) { 2608 if (osr->comp_level() == CompLevel_highest_tier) { 2609 // Found the best possible - return it. 2610 return osr; 2611 } 2612 best = osr; 2613 } 2614 } 2615 } 2616 osr = osr->osr_link(); 2617 } 2618 if (best != NULL && best->comp_level() >= comp_level && match_level == false) { 2619 return best; 2620 } 2621 return NULL; 2622 } 2623 2624 bool InstanceKlass::add_member_name(Handle mem_name) { 2625 jweak mem_name_wref = JNIHandles::make_weak_global(mem_name); 2626 MutexLocker ml(MemberNameTable_lock); 2627 DEBUG_ONLY(NoSafepointVerifier nsv); 2628 2629 // Check if method has been redefined while taking out MemberNameTable_lock, if so 2630 // return false. We cannot cache obsolete methods. They will crash when the function 2631 // is called! 2632 Method* method = (Method*)java_lang_invoke_MemberName::vmtarget(mem_name()); 2633 if (method->is_obsolete()) { 2634 return false; 2635 } else if (method->is_old()) { 2636 // Replace method with redefined version 2637 java_lang_invoke_MemberName::set_vmtarget(mem_name(), method_with_idnum(method->method_idnum())); 2638 } 2639 2640 if (_member_names == NULL) { 2641 _member_names = new (ResourceObj::C_HEAP, mtClass) MemberNameTable(idnum_allocated_count()); 2642 } 2643 _member_names->add_member_name(mem_name_wref); 2644 return true; 2645 } 2646 2647 // ----------------------------------------------------------------------------------------------------- 2648 // Printing 2649 2650 #ifndef PRODUCT 2651 2652 #define BULLET " - " 2653 2654 static const char* state_names[] = { 2655 "allocated", "loaded", "linked", "being_initialized", "fully_initialized", "initialization_error" 2656 }; 2657 2658 static void print_vtable(intptr_t* start, int len, outputStream* st) { 2659 for (int i = 0; i < len; i++) { 2660 intptr_t e = start[i]; 2661 st->print("%d : " INTPTR_FORMAT, i, e); 2662 if (e != 0 && ((Metadata*)e)->is_metaspace_object()) { 2663 st->print(" "); 2664 ((Metadata*)e)->print_value_on(st); 2665 } 2666 st->cr(); 2667 } 2668 } 2669 2670 void InstanceKlass::print_on(outputStream* st) const { 2671 assert(is_klass(), "must be klass"); 2672 Klass::print_on(st); 2673 2674 st->print(BULLET"instance size: %d", size_helper()); st->cr(); 2675 st->print(BULLET"klass size: %d", size()); st->cr(); 2676 st->print(BULLET"access: "); access_flags().print_on(st); st->cr(); 2677 st->print(BULLET"state: "); st->print_cr("%s", state_names[_init_state]); 2678 st->print(BULLET"name: "); name()->print_value_on(st); st->cr(); 2679 st->print(BULLET"super: "); super()->print_value_on_maybe_null(st); st->cr(); 2680 st->print(BULLET"sub: "); 2681 Klass* sub = subklass(); 2682 int n; 2683 for (n = 0; sub != NULL; n++, sub = sub->next_sibling()) { 2684 if (n < MaxSubklassPrintSize) { 2685 sub->print_value_on(st); 2686 st->print(" "); 2687 } 2688 } 2689 if (n >= MaxSubklassPrintSize) st->print("(" INTX_FORMAT " more klasses...)", n - MaxSubklassPrintSize); 2690 st->cr(); 2691 2692 if (is_interface()) { 2693 st->print_cr(BULLET"nof implementors: %d", nof_implementors()); 2694 if (nof_implementors() == 1) { 2695 st->print_cr(BULLET"implementor: "); 2696 st->print(" "); 2697 implementor()->print_value_on(st); 2698 st->cr(); 2699 } 2700 } 2701 2702 st->print(BULLET"arrays: "); array_klasses()->print_value_on_maybe_null(st); st->cr(); 2703 st->print(BULLET"methods: "); methods()->print_value_on(st); st->cr(); 2704 if (Verbose || WizardMode) { 2705 Array<Method*>* method_array = methods(); 2706 for (int i = 0; i < method_array->length(); i++) { 2707 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr(); 2708 } 2709 } 2710 st->print(BULLET"method ordering: "); method_ordering()->print_value_on(st); st->cr(); 2711 st->print(BULLET"default_methods: "); default_methods()->print_value_on(st); st->cr(); 2712 if (Verbose && default_methods() != NULL) { 2713 Array<Method*>* method_array = default_methods(); 2714 for (int i = 0; i < method_array->length(); i++) { 2715 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr(); 2716 } 2717 } 2718 if (default_vtable_indices() != NULL) { 2719 st->print(BULLET"default vtable indices: "); default_vtable_indices()->print_value_on(st); st->cr(); 2720 } 2721 st->print(BULLET"local interfaces: "); local_interfaces()->print_value_on(st); st->cr(); 2722 st->print(BULLET"trans. interfaces: "); transitive_interfaces()->print_value_on(st); st->cr(); 2723 st->print(BULLET"constants: "); constants()->print_value_on(st); st->cr(); 2724 if (class_loader_data() != NULL) { 2725 st->print(BULLET"class loader data: "); 2726 class_loader_data()->print_value_on(st); 2727 st->cr(); 2728 } 2729 st->print(BULLET"host class: "); host_klass()->print_value_on_maybe_null(st); st->cr(); 2730 if (source_file_name() != NULL) { 2731 st->print(BULLET"source file: "); 2732 source_file_name()->print_value_on(st); 2733 st->cr(); 2734 } 2735 if (source_debug_extension() != NULL) { 2736 st->print(BULLET"source debug extension: "); 2737 st->print("%s", source_debug_extension()); 2738 st->cr(); 2739 } 2740 st->print(BULLET"class annotations: "); class_annotations()->print_value_on(st); st->cr(); 2741 st->print(BULLET"class type annotations: "); class_type_annotations()->print_value_on(st); st->cr(); 2742 st->print(BULLET"field annotations: "); fields_annotations()->print_value_on(st); st->cr(); 2743 st->print(BULLET"field type annotations: "); fields_type_annotations()->print_value_on(st); st->cr(); 2744 { 2745 bool have_pv = false; 2746 // previous versions are linked together through the InstanceKlass 2747 for (InstanceKlass* pv_node = _previous_versions; 2748 pv_node != NULL; 2749 pv_node = pv_node->previous_versions()) { 2750 if (!have_pv) 2751 st->print(BULLET"previous version: "); 2752 have_pv = true; 2753 pv_node->constants()->print_value_on(st); 2754 } 2755 if (have_pv) st->cr(); 2756 } 2757 2758 if (generic_signature() != NULL) { 2759 st->print(BULLET"generic signature: "); 2760 generic_signature()->print_value_on(st); 2761 st->cr(); 2762 } 2763 st->print(BULLET"inner classes: "); inner_classes()->print_value_on(st); st->cr(); 2764 st->print(BULLET"java mirror: "); java_mirror()->print_value_on(st); st->cr(); 2765 st->print(BULLET"vtable length %d (start addr: " INTPTR_FORMAT ")", vtable_length(), p2i(start_of_vtable())); st->cr(); 2766 if (vtable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_vtable(), vtable_length(), st); 2767 st->print(BULLET"itable length %d (start addr: " INTPTR_FORMAT ")", itable_length(), p2i(start_of_itable())); st->cr(); 2768 if (itable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_itable(), itable_length(), st); 2769 st->print_cr(BULLET"---- static fields (%d words):", static_field_size()); 2770 FieldPrinter print_static_field(st); 2771 ((InstanceKlass*)this)->do_local_static_fields(&print_static_field); 2772 st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size()); 2773 FieldPrinter print_nonstatic_field(st); 2774 InstanceKlass* ik = const_cast<InstanceKlass*>(this); 2775 ik->do_nonstatic_fields(&print_nonstatic_field); 2776 2777 st->print(BULLET"non-static oop maps: "); 2778 OopMapBlock* map = start_of_nonstatic_oop_maps(); 2779 OopMapBlock* end_map = map + nonstatic_oop_map_count(); 2780 while (map < end_map) { 2781 st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1)); 2782 map++; 2783 } 2784 st->cr(); 2785 } 2786 2787 #endif //PRODUCT 2788 2789 void InstanceKlass::print_value_on(outputStream* st) const { 2790 assert(is_klass(), "must be klass"); 2791 if (Verbose || WizardMode) access_flags().print_on(st); 2792 name()->print_value_on(st); 2793 } 2794 2795 #ifndef PRODUCT 2796 2797 void FieldPrinter::do_field(fieldDescriptor* fd) { 2798 _st->print(BULLET); 2799 if (_obj == NULL) { 2800 fd->print_on(_st); 2801 _st->cr(); 2802 } else { 2803 fd->print_on_for(_st, _obj); 2804 _st->cr(); 2805 } 2806 } 2807 2808 2809 void InstanceKlass::oop_print_on(oop obj, outputStream* st) { 2810 Klass::oop_print_on(obj, st); 2811 2812 if (this == SystemDictionary::String_klass()) { 2813 typeArrayOop value = java_lang_String::value(obj); 2814 juint length = java_lang_String::length(obj); 2815 if (value != NULL && 2816 value->is_typeArray() && 2817 length <= (juint) value->length()) { 2818 st->print(BULLET"string: "); 2819 java_lang_String::print(obj, st); 2820 st->cr(); 2821 if (!WizardMode) return; // that is enough 2822 } 2823 } 2824 2825 st->print_cr(BULLET"---- fields (total size %d words):", oop_size(obj)); 2826 FieldPrinter print_field(st, obj); 2827 do_nonstatic_fields(&print_field); 2828 2829 if (this == SystemDictionary::Class_klass()) { 2830 st->print(BULLET"signature: "); 2831 java_lang_Class::print_signature(obj, st); 2832 st->cr(); 2833 Klass* mirrored_klass = java_lang_Class::as_Klass(obj); 2834 st->print(BULLET"fake entry for mirror: "); 2835 mirrored_klass->print_value_on_maybe_null(st); 2836 st->cr(); 2837 Klass* array_klass = java_lang_Class::array_klass(obj); 2838 st->print(BULLET"fake entry for array: "); 2839 array_klass->print_value_on_maybe_null(st); 2840 st->cr(); 2841 st->print_cr(BULLET"fake entry for oop_size: %d", java_lang_Class::oop_size(obj)); 2842 st->print_cr(BULLET"fake entry for static_oop_field_count: %d", java_lang_Class::static_oop_field_count(obj)); 2843 Klass* real_klass = java_lang_Class::as_Klass(obj); 2844 if (real_klass != NULL && real_klass->is_instance_klass()) { 2845 InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field); 2846 } 2847 } else if (this == SystemDictionary::MethodType_klass()) { 2848 st->print(BULLET"signature: "); 2849 java_lang_invoke_MethodType::print_signature(obj, st); 2850 st->cr(); 2851 } 2852 } 2853 2854 #endif //PRODUCT 2855 2856 void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) { 2857 st->print("a "); 2858 name()->print_value_on(st); 2859 obj->print_address_on(st); 2860 if (this == SystemDictionary::String_klass() 2861 && java_lang_String::value(obj) != NULL) { 2862 ResourceMark rm; 2863 int len = java_lang_String::length(obj); 2864 int plen = (len < 24 ? len : 12); 2865 char* str = java_lang_String::as_utf8_string(obj, 0, plen); 2866 st->print(" = \"%s\"", str); 2867 if (len > plen) 2868 st->print("...[%d]", len); 2869 } else if (this == SystemDictionary::Class_klass()) { 2870 Klass* k = java_lang_Class::as_Klass(obj); 2871 st->print(" = "); 2872 if (k != NULL) { 2873 k->print_value_on(st); 2874 } else { 2875 const char* tname = type2name(java_lang_Class::primitive_type(obj)); 2876 st->print("%s", tname ? tname : "type?"); 2877 } 2878 } else if (this == SystemDictionary::MethodType_klass()) { 2879 st->print(" = "); 2880 java_lang_invoke_MethodType::print_signature(obj, st); 2881 } else if (java_lang_boxing_object::is_instance(obj)) { 2882 st->print(" = "); 2883 java_lang_boxing_object::print(obj, st); 2884 } else if (this == SystemDictionary::LambdaForm_klass()) { 2885 oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj); 2886 if (vmentry != NULL) { 2887 st->print(" => "); 2888 vmentry->print_value_on(st); 2889 } 2890 } else if (this == SystemDictionary::MemberName_klass()) { 2891 Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj); 2892 if (vmtarget != NULL) { 2893 st->print(" = "); 2894 vmtarget->print_value_on(st); 2895 } else { 2896 java_lang_invoke_MemberName::clazz(obj)->print_value_on(st); 2897 st->print("."); 2898 java_lang_invoke_MemberName::name(obj)->print_value_on(st); 2899 } 2900 } 2901 } 2902 2903 const char* InstanceKlass::internal_name() const { 2904 return external_name(); 2905 } 2906 2907 #if INCLUDE_SERVICES 2908 // Size Statistics 2909 void InstanceKlass::collect_statistics(KlassSizeStats *sz) const { 2910 Klass::collect_statistics(sz); 2911 2912 sz->_inst_size = HeapWordSize * size_helper(); 2913 sz->_vtab_bytes = HeapWordSize * align_object_offset(vtable_length()); 2914 sz->_itab_bytes = HeapWordSize * align_object_offset(itable_length()); 2915 sz->_nonstatic_oopmap_bytes = HeapWordSize * 2916 ((is_interface() || is_anonymous()) ? 2917 align_object_offset(nonstatic_oop_map_size()) : 2918 nonstatic_oop_map_size()); 2919 2920 int n = 0; 2921 n += (sz->_methods_array_bytes = sz->count_array(methods())); 2922 n += (sz->_method_ordering_bytes = sz->count_array(method_ordering())); 2923 n += (sz->_local_interfaces_bytes = sz->count_array(local_interfaces())); 2924 n += (sz->_transitive_interfaces_bytes = sz->count_array(transitive_interfaces())); 2925 n += (sz->_fields_bytes = sz->count_array(fields())); 2926 n += (sz->_inner_classes_bytes = sz->count_array(inner_classes())); 2927 sz->_ro_bytes += n; 2928 2929 const ConstantPool* cp = constants(); 2930 if (cp) { 2931 cp->collect_statistics(sz); 2932 } 2933 2934 const Annotations* anno = annotations(); 2935 if (anno) { 2936 anno->collect_statistics(sz); 2937 } 2938 2939 const Array<Method*>* methods_array = methods(); 2940 if (methods()) { 2941 for (int i = 0; i < methods_array->length(); i++) { 2942 Method* method = methods_array->at(i); 2943 if (method) { 2944 sz->_method_count ++; 2945 method->collect_statistics(sz); 2946 } 2947 } 2948 } 2949 } 2950 #endif // INCLUDE_SERVICES 2951 2952 // Verification 2953 2954 class VerifyFieldClosure: public OopClosure { 2955 protected: 2956 template <class T> void do_oop_work(T* p) { 2957 oop obj = oopDesc::load_decode_heap_oop(p); 2958 if (!obj->is_oop_or_null()) { 2959 tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p2i(p), p2i(obj)); 2960 Universe::print_on(tty); 2961 guarantee(false, "boom"); 2962 } 2963 } 2964 public: 2965 virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); } 2966 virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); } 2967 }; 2968 2969 void InstanceKlass::verify_on(outputStream* st) { 2970 #ifndef PRODUCT 2971 // Avoid redundant verifies, this really should be in product. 2972 if (_verify_count == Universe::verify_count()) return; 2973 _verify_count = Universe::verify_count(); 2974 #endif 2975 2976 // Verify Klass 2977 Klass::verify_on(st); 2978 2979 // Verify that klass is present in ClassLoaderData 2980 guarantee(class_loader_data()->contains_klass(this), 2981 "this class isn't found in class loader data"); 2982 2983 // Verify vtables 2984 if (is_linked()) { 2985 ResourceMark rm; 2986 // $$$ This used to be done only for m/s collections. Doing it 2987 // always seemed a valid generalization. (DLD -- 6/00) 2988 vtable()->verify(st); 2989 } 2990 2991 // Verify first subklass 2992 if (subklass() != NULL) { 2993 guarantee(subklass()->is_klass(), "should be klass"); 2994 } 2995 2996 // Verify siblings 2997 Klass* super = this->super(); 2998 Klass* sib = next_sibling(); 2999 if (sib != NULL) { 3000 if (sib == this) { 3001 fatal("subclass points to itself " PTR_FORMAT, p2i(sib)); 3002 } 3003 3004 guarantee(sib->is_klass(), "should be klass"); 3005 guarantee(sib->super() == super, "siblings should have same superklass"); 3006 } 3007 3008 // Verify implementor fields 3009 Klass* im = implementor(); 3010 if (im != NULL) { 3011 guarantee(is_interface(), "only interfaces should have implementor set"); 3012 guarantee(im->is_klass(), "should be klass"); 3013 guarantee(!im->is_interface() || im == this, 3014 "implementors cannot be interfaces"); 3015 } 3016 3017 // Verify local interfaces 3018 if (local_interfaces()) { 3019 Array<Klass*>* local_interfaces = this->local_interfaces(); 3020 for (int j = 0; j < local_interfaces->length(); j++) { 3021 Klass* e = local_interfaces->at(j); 3022 guarantee(e->is_klass() && e->is_interface(), "invalid local interface"); 3023 } 3024 } 3025 3026 // Verify transitive interfaces 3027 if (transitive_interfaces() != NULL) { 3028 Array<Klass*>* transitive_interfaces = this->transitive_interfaces(); 3029 for (int j = 0; j < transitive_interfaces->length(); j++) { 3030 Klass* e = transitive_interfaces->at(j); 3031 guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface"); 3032 } 3033 } 3034 3035 // Verify methods 3036 if (methods() != NULL) { 3037 Array<Method*>* methods = this->methods(); 3038 for (int j = 0; j < methods->length(); j++) { 3039 guarantee(methods->at(j)->is_method(), "non-method in methods array"); 3040 } 3041 for (int j = 0; j < methods->length() - 1; j++) { 3042 Method* m1 = methods->at(j); 3043 Method* m2 = methods->at(j + 1); 3044 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly"); 3045 } 3046 } 3047 3048 // Verify method ordering 3049 if (method_ordering() != NULL) { 3050 Array<int>* method_ordering = this->method_ordering(); 3051 int length = method_ordering->length(); 3052 if (JvmtiExport::can_maintain_original_method_order() || 3053 ((UseSharedSpaces || DumpSharedSpaces) && length != 0)) { 3054 guarantee(length == methods()->length(), "invalid method ordering length"); 3055 jlong sum = 0; 3056 for (int j = 0; j < length; j++) { 3057 int original_index = method_ordering->at(j); 3058 guarantee(original_index >= 0, "invalid method ordering index"); 3059 guarantee(original_index < length, "invalid method ordering index"); 3060 sum += original_index; 3061 } 3062 // Verify sum of indices 0,1,...,length-1 3063 guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum"); 3064 } else { 3065 guarantee(length == 0, "invalid method ordering length"); 3066 } 3067 } 3068 3069 // Verify default methods 3070 if (default_methods() != NULL) { 3071 Array<Method*>* methods = this->default_methods(); 3072 for (int j = 0; j < methods->length(); j++) { 3073 guarantee(methods->at(j)->is_method(), "non-method in methods array"); 3074 } 3075 for (int j = 0; j < methods->length() - 1; j++) { 3076 Method* m1 = methods->at(j); 3077 Method* m2 = methods->at(j + 1); 3078 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly"); 3079 } 3080 } 3081 3082 // Verify JNI static field identifiers 3083 if (jni_ids() != NULL) { 3084 jni_ids()->verify(this); 3085 } 3086 3087 // Verify other fields 3088 if (array_klasses() != NULL) { 3089 guarantee(array_klasses()->is_klass(), "should be klass"); 3090 } 3091 if (constants() != NULL) { 3092 guarantee(constants()->is_constantPool(), "should be constant pool"); 3093 } 3094 const Klass* host = host_klass(); 3095 if (host != NULL) { 3096 guarantee(host->is_klass(), "should be klass"); 3097 } 3098 } 3099 3100 void InstanceKlass::oop_verify_on(oop obj, outputStream* st) { 3101 Klass::oop_verify_on(obj, st); 3102 VerifyFieldClosure blk; 3103 obj->oop_iterate_no_header(&blk); 3104 } 3105 3106 3107 // JNIid class for jfieldIDs only 3108 // Note to reviewers: 3109 // These JNI functions are just moved over to column 1 and not changed 3110 // in the compressed oops workspace. 3111 JNIid::JNIid(Klass* holder, int offset, JNIid* next) { 3112 _holder = holder; 3113 _offset = offset; 3114 _next = next; 3115 debug_only(_is_static_field_id = false;) 3116 } 3117 3118 3119 JNIid* JNIid::find(int offset) { 3120 JNIid* current = this; 3121 while (current != NULL) { 3122 if (current->offset() == offset) return current; 3123 current = current->next(); 3124 } 3125 return NULL; 3126 } 3127 3128 void JNIid::deallocate(JNIid* current) { 3129 while (current != NULL) { 3130 JNIid* next = current->next(); 3131 delete current; 3132 current = next; 3133 } 3134 } 3135 3136 3137 void JNIid::verify(Klass* holder) { 3138 int first_field_offset = InstanceMirrorKlass::offset_of_static_fields(); 3139 int end_field_offset; 3140 end_field_offset = first_field_offset + (InstanceKlass::cast(holder)->static_field_size() * wordSize); 3141 3142 JNIid* current = this; 3143 while (current != NULL) { 3144 guarantee(current->holder() == holder, "Invalid klass in JNIid"); 3145 #ifdef ASSERT 3146 int o = current->offset(); 3147 if (current->is_static_field_id()) { 3148 guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid"); 3149 } 3150 #endif 3151 current = current->next(); 3152 } 3153 } 3154 3155 3156 #ifdef ASSERT 3157 void InstanceKlass::set_init_state(ClassState state) { 3158 bool good_state = is_shared() ? (_init_state <= state) 3159 : (_init_state < state); 3160 assert(good_state || state == allocated, "illegal state transition"); 3161 _init_state = (u1)state; 3162 } 3163 #endif 3164 3165 3166 3167 // RedefineClasses() support for previous versions: 3168 int InstanceKlass::_previous_version_count = 0; 3169 3170 // Purge previous versions before adding new previous versions of the class. 3171 void InstanceKlass::purge_previous_versions(InstanceKlass* ik) { 3172 if (ik->previous_versions() != NULL) { 3173 // This klass has previous versions so see what we can cleanup 3174 // while it is safe to do so. 3175 3176 int deleted_count = 0; // leave debugging breadcrumbs 3177 int live_count = 0; 3178 ClassLoaderData* loader_data = ik->class_loader_data(); 3179 assert(loader_data != NULL, "should never be null"); 3180 3181 // RC_TRACE macro has an embedded ResourceMark 3182 RC_TRACE(0x00000200, ("purge: %s: previous versions", ik->external_name())); 3183 3184 // previous versions are linked together through the InstanceKlass 3185 InstanceKlass* pv_node = ik->previous_versions(); 3186 InstanceKlass* last = ik; 3187 int version = 0; 3188 3189 // check the previous versions list 3190 for (; pv_node != NULL; ) { 3191 3192 ConstantPool* pvcp = pv_node->constants(); 3193 assert(pvcp != NULL, "cp ref was unexpectedly cleared"); 3194 3195 if (!pvcp->on_stack()) { 3196 // If the constant pool isn't on stack, none of the methods 3197 // are executing. Unlink this previous_version. 3198 // The previous version InstanceKlass is on the ClassLoaderData deallocate list 3199 // so will be deallocated during the next phase of class unloading. 3200 RC_TRACE(0x00000200, ("purge: previous version " INTPTR_FORMAT " is dead", 3201 p2i(pv_node))); 3202 // For debugging purposes. 3203 pv_node->set_is_scratch_class(); 3204 pv_node->class_loader_data()->add_to_deallocate_list(pv_node); 3205 pv_node = pv_node->previous_versions(); 3206 last->link_previous_versions(pv_node); 3207 deleted_count++; 3208 version++; 3209 continue; 3210 } else { 3211 RC_TRACE(0x00000200, ("purge: previous version " INTPTR_FORMAT " is alive", 3212 p2i(pv_node))); 3213 assert(pvcp->pool_holder() != NULL, "Constant pool with no holder"); 3214 guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack"); 3215 live_count++; 3216 } 3217 3218 // At least one method is live in this previous version. 3219 // Reset dead EMCP methods not to get breakpoints. 3220 // All methods are deallocated when all of the methods for this class are no 3221 // longer running. 3222 Array<Method*>* method_refs = pv_node->methods(); 3223 if (method_refs != NULL) { 3224 RC_TRACE(0x00000200, ("purge: previous methods length=%d", 3225 method_refs->length())); 3226 for (int j = 0; j < method_refs->length(); j++) { 3227 Method* method = method_refs->at(j); 3228 3229 if (!method->on_stack()) { 3230 // no breakpoints for non-running methods 3231 if (method->is_running_emcp()) { 3232 method->set_running_emcp(false); 3233 } 3234 } else { 3235 assert (method->is_obsolete() || method->is_running_emcp(), 3236 "emcp method cannot run after emcp bit is cleared"); 3237 // RC_TRACE macro has an embedded ResourceMark 3238 RC_TRACE(0x00000200, 3239 ("purge: %s(%s): prev method @%d in version @%d is alive", 3240 method->name()->as_C_string(), 3241 method->signature()->as_C_string(), j, version)); 3242 } 3243 } 3244 } 3245 // next previous version 3246 last = pv_node; 3247 pv_node = pv_node->previous_versions(); 3248 version++; 3249 } 3250 RC_TRACE(0x00000200, 3251 ("purge: previous version stats: live=%d, deleted=%d", live_count, 3252 deleted_count)); 3253 } 3254 } 3255 3256 void InstanceKlass::mark_newly_obsolete_methods(Array<Method*>* old_methods, 3257 int emcp_method_count) { 3258 int obsolete_method_count = old_methods->length() - emcp_method_count; 3259 3260 if (emcp_method_count != 0 && obsolete_method_count != 0 && 3261 _previous_versions != NULL) { 3262 // We have a mix of obsolete and EMCP methods so we have to 3263 // clear out any matching EMCP method entries the hard way. 3264 int local_count = 0; 3265 for (int i = 0; i < old_methods->length(); i++) { 3266 Method* old_method = old_methods->at(i); 3267 if (old_method->is_obsolete()) { 3268 // only obsolete methods are interesting 3269 Symbol* m_name = old_method->name(); 3270 Symbol* m_signature = old_method->signature(); 3271 3272 // previous versions are linked together through the InstanceKlass 3273 int j = 0; 3274 for (InstanceKlass* prev_version = _previous_versions; 3275 prev_version != NULL; 3276 prev_version = prev_version->previous_versions(), j++) { 3277 3278 Array<Method*>* method_refs = prev_version->methods(); 3279 for (int k = 0; k < method_refs->length(); k++) { 3280 Method* method = method_refs->at(k); 3281 3282 if (!method->is_obsolete() && 3283 method->name() == m_name && 3284 method->signature() == m_signature) { 3285 // The current RedefineClasses() call has made all EMCP 3286 // versions of this method obsolete so mark it as obsolete 3287 RC_TRACE(0x00000400, 3288 ("add: %s(%s): flush obsolete method @%d in version @%d", 3289 m_name->as_C_string(), m_signature->as_C_string(), k, j)); 3290 3291 method->set_is_obsolete(); 3292 break; 3293 } 3294 } 3295 3296 // The previous loop may not find a matching EMCP method, but 3297 // that doesn't mean that we can optimize and not go any 3298 // further back in the PreviousVersion generations. The EMCP 3299 // method for this generation could have already been made obsolete, 3300 // but there still may be an older EMCP method that has not 3301 // been made obsolete. 3302 } 3303 3304 if (++local_count >= obsolete_method_count) { 3305 // no more obsolete methods so bail out now 3306 break; 3307 } 3308 } 3309 } 3310 } 3311 } 3312 3313 // Save the scratch_class as the previous version if any of the methods are running. 3314 // The previous_versions are used to set breakpoints in EMCP methods and they are 3315 // also used to clean MethodData links to redefined methods that are no longer running. 3316 void InstanceKlass::add_previous_version(instanceKlassHandle scratch_class, 3317 int emcp_method_count) { 3318 assert(Thread::current()->is_VM_thread(), 3319 "only VMThread can add previous versions"); 3320 3321 // RC_TRACE macro has an embedded ResourceMark 3322 RC_TRACE(0x00000400, ("adding previous version ref for %s, EMCP_cnt=%d", 3323 scratch_class->external_name(), emcp_method_count)); 3324 3325 // Clean out old previous versions 3326 purge_previous_versions(this); 3327 3328 // Mark newly obsolete methods in remaining previous versions. An EMCP method from 3329 // a previous redefinition may be made obsolete by this redefinition. 3330 Array<Method*>* old_methods = scratch_class->methods(); 3331 mark_newly_obsolete_methods(old_methods, emcp_method_count); 3332 3333 // If the constant pool for this previous version of the class 3334 // is not marked as being on the stack, then none of the methods 3335 // in this previous version of the class are on the stack so 3336 // we don't need to add this as a previous version. 3337 ConstantPool* cp_ref = scratch_class->constants(); 3338 if (!cp_ref->on_stack()) { 3339 RC_TRACE(0x00000400, ("add: scratch class not added; no methods are running")); 3340 // For debugging purposes. 3341 scratch_class->set_is_scratch_class(); 3342 scratch_class->class_loader_data()->add_to_deallocate_list(scratch_class()); 3343 // Update count for class unloading. 3344 _previous_version_count--; 3345 return; 3346 } 3347 3348 if (emcp_method_count != 0) { 3349 // At least one method is still running, check for EMCP methods 3350 for (int i = 0; i < old_methods->length(); i++) { 3351 Method* old_method = old_methods->at(i); 3352 if (!old_method->is_obsolete() && old_method->on_stack()) { 3353 // if EMCP method (not obsolete) is on the stack, mark as EMCP so that 3354 // we can add breakpoints for it. 3355 3356 // We set the method->on_stack bit during safepoints for class redefinition 3357 // and use this bit to set the is_running_emcp bit. 3358 // After the safepoint, the on_stack bit is cleared and the running emcp 3359 // method may exit. If so, we would set a breakpoint in a method that 3360 // is never reached, but this won't be noticeable to the programmer. 3361 old_method->set_running_emcp(true); 3362 RC_TRACE(0x00000400, ("add: EMCP method %s is on_stack " INTPTR_FORMAT, 3363 old_method->name_and_sig_as_C_string(), p2i(old_method))); 3364 } else if (!old_method->is_obsolete()) { 3365 RC_TRACE(0x00000400, ("add: EMCP method %s is NOT on_stack " INTPTR_FORMAT, 3366 old_method->name_and_sig_as_C_string(), p2i(old_method))); 3367 } 3368 } 3369 } 3370 3371 // Add previous version if any methods are still running. 3372 RC_TRACE(0x00000400, ("add: scratch class added; one of its methods is on_stack")); 3373 assert(scratch_class->previous_versions() == NULL, "shouldn't have a previous version"); 3374 scratch_class->link_previous_versions(previous_versions()); 3375 link_previous_versions(scratch_class()); 3376 // Update count for class unloading. 3377 _previous_version_count++; 3378 } // end add_previous_version() 3379 3380 3381 Method* InstanceKlass::method_with_idnum(int idnum) { 3382 Method* m = NULL; 3383 if (idnum < methods()->length()) { 3384 m = methods()->at(idnum); 3385 } 3386 if (m == NULL || m->method_idnum() != idnum) { 3387 for (int index = 0; index < methods()->length(); ++index) { 3388 m = methods()->at(index); 3389 if (m->method_idnum() == idnum) { 3390 return m; 3391 } 3392 } 3393 // None found, return null for the caller to handle. 3394 return NULL; 3395 } 3396 return m; 3397 } 3398 3399 3400 Method* InstanceKlass::method_with_orig_idnum(int idnum) { 3401 if (idnum >= methods()->length()) { 3402 return NULL; 3403 } 3404 Method* m = methods()->at(idnum); 3405 if (m != NULL && m->orig_method_idnum() == idnum) { 3406 return m; 3407 } 3408 // Obsolete method idnum does not match the original idnum 3409 for (int index = 0; index < methods()->length(); ++index) { 3410 m = methods()->at(index); 3411 if (m->orig_method_idnum() == idnum) { 3412 return m; 3413 } 3414 } 3415 // None found, return null for the caller to handle. 3416 return NULL; 3417 } 3418 3419 3420 Method* InstanceKlass::method_with_orig_idnum(int idnum, int version) { 3421 InstanceKlass* holder = get_klass_version(version); 3422 if (holder == NULL) { 3423 return NULL; // The version of klass is gone, no method is found 3424 } 3425 Method* method = holder->method_with_orig_idnum(idnum); 3426 return method; 3427 } 3428 3429 3430 jint InstanceKlass::get_cached_class_file_len() { 3431 return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file); 3432 } 3433 3434 unsigned char * InstanceKlass::get_cached_class_file_bytes() { 3435 return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file); 3436 }