1 /* 2 * Copyright (c) 1997, 2017, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25 #include "precompiled.hpp" 26 #include "aot/aotLoader.hpp" 27 #include "classfile/classFileParser.hpp" 28 #include "classfile/classFileStream.hpp" 29 #include "classfile/classLoader.hpp" 30 #include "classfile/javaClasses.hpp" 31 #include "classfile/moduleEntry.hpp" 32 #include "classfile/systemDictionary.hpp" 33 #include "classfile/systemDictionaryShared.hpp" 34 #include "classfile/verifier.hpp" 35 #include "classfile/vmSymbols.hpp" 36 #include "code/dependencyContext.hpp" 37 #include "compiler/compileBroker.hpp" 38 #include "gc/shared/collectedHeap.inline.hpp" 39 #include "gc/shared/specialized_oop_closures.hpp" 40 #include "interpreter/oopMapCache.hpp" 41 #include "interpreter/rewriter.hpp" 42 #include "jvmtifiles/jvmti.h" 43 #include "logging/log.hpp" 44 #include "logging/logMessage.hpp" 45 #include "logging/logStream.hpp" 46 #include "memory/heapInspection.hpp" 47 #include "memory/iterator.inline.hpp" 48 #include "memory/metadataFactory.hpp" 49 #include "memory/metaspaceClosure.hpp" 50 #include "memory/metaspaceShared.hpp" 51 #include "memory/oopFactory.hpp" 52 #include "memory/resourceArea.hpp" 53 #include "oops/fieldStreams.hpp" 54 #include "oops/instanceClassLoaderKlass.hpp" 55 #include "oops/instanceKlass.inline.hpp" 56 #include "oops/instanceMirrorKlass.hpp" 57 #include "oops/instanceOop.hpp" 58 #include "oops/klass.inline.hpp" 59 #include "oops/method.hpp" 60 #include "oops/oop.inline.hpp" 61 #include "oops/symbol.hpp" 62 #include "prims/jvm.h" 63 #include "prims/jvmtiExport.hpp" 64 #include "prims/jvmtiRedefineClasses.hpp" 65 #include "prims/jvmtiThreadState.hpp" 66 #include "prims/methodComparator.hpp" 67 #include "runtime/atomic.hpp" 68 #include "runtime/fieldDescriptor.hpp" 69 #include "runtime/handles.inline.hpp" 70 #include "runtime/javaCalls.hpp" 71 #include "runtime/mutexLocker.hpp" 72 #include "runtime/orderAccess.inline.hpp" 73 #include "runtime/thread.inline.hpp" 74 #include "services/classLoadingService.hpp" 75 #include "services/threadService.hpp" 76 #include "utilities/dtrace.hpp" 77 #include "utilities/macros.hpp" 78 #include "utilities/stringUtils.hpp" 79 #ifdef COMPILER1 80 #include "c1/c1_Compiler.hpp" 81 #endif 82 83 #ifdef DTRACE_ENABLED 84 85 86 #define HOTSPOT_CLASS_INITIALIZATION_required HOTSPOT_CLASS_INITIALIZATION_REQUIRED 87 #define HOTSPOT_CLASS_INITIALIZATION_recursive HOTSPOT_CLASS_INITIALIZATION_RECURSIVE 88 #define HOTSPOT_CLASS_INITIALIZATION_concurrent HOTSPOT_CLASS_INITIALIZATION_CONCURRENT 89 #define HOTSPOT_CLASS_INITIALIZATION_erroneous HOTSPOT_CLASS_INITIALIZATION_ERRONEOUS 90 #define HOTSPOT_CLASS_INITIALIZATION_super__failed HOTSPOT_CLASS_INITIALIZATION_SUPER_FAILED 91 #define HOTSPOT_CLASS_INITIALIZATION_clinit HOTSPOT_CLASS_INITIALIZATION_CLINIT 92 #define HOTSPOT_CLASS_INITIALIZATION_error HOTSPOT_CLASS_INITIALIZATION_ERROR 93 #define HOTSPOT_CLASS_INITIALIZATION_end HOTSPOT_CLASS_INITIALIZATION_END 94 #define DTRACE_CLASSINIT_PROBE(type, thread_type) \ 95 { \ 96 char* data = NULL; \ 97 int len = 0; \ 98 Symbol* clss_name = name(); \ 99 if (clss_name != NULL) { \ 100 data = (char*)clss_name->bytes(); \ 101 len = clss_name->utf8_length(); \ 102 } \ 103 HOTSPOT_CLASS_INITIALIZATION_##type( \ 104 data, len, (void*)class_loader(), thread_type); \ 105 } 106 107 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait) \ 108 { \ 109 char* data = NULL; \ 110 int len = 0; \ 111 Symbol* clss_name = name(); \ 112 if (clss_name != NULL) { \ 113 data = (char*)clss_name->bytes(); \ 114 len = clss_name->utf8_length(); \ 115 } \ 116 HOTSPOT_CLASS_INITIALIZATION_##type( \ 117 data, len, (void*)class_loader(), thread_type, wait); \ 118 } 119 120 #else // ndef DTRACE_ENABLED 121 122 #define DTRACE_CLASSINIT_PROBE(type, thread_type) 123 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait) 124 125 #endif // ndef DTRACE_ENABLED 126 127 volatile int InstanceKlass::_total_instanceKlass_count = 0; 128 129 static inline bool is_class_loader(const Symbol* class_name, 130 const ClassFileParser& parser) { 131 assert(class_name != NULL, "invariant"); 132 133 if (class_name == vmSymbols::java_lang_ClassLoader()) { 134 return true; 135 } 136 137 if (SystemDictionary::ClassLoader_klass_loaded()) { 138 const Klass* const super_klass = parser.super_klass(); 139 if (super_klass != NULL) { 140 if (super_klass->is_subtype_of(SystemDictionary::ClassLoader_klass())) { 141 return true; 142 } 143 } 144 } 145 return false; 146 } 147 148 InstanceKlass* InstanceKlass::allocate_instance_klass(const ClassFileParser& parser, TRAPS) { 149 const int size = InstanceKlass::size(parser.vtable_size(), 150 parser.itable_size(), 151 nonstatic_oop_map_size(parser.total_oop_map_count()), 152 parser.is_interface(), 153 parser.is_anonymous(), 154 should_store_fingerprint()); 155 156 const Symbol* const class_name = parser.class_name(); 157 assert(class_name != NULL, "invariant"); 158 ClassLoaderData* loader_data = parser.loader_data(); 159 assert(loader_data != NULL, "invariant"); 160 161 InstanceKlass* ik; 162 163 // Allocation 164 if (REF_NONE == parser.reference_type()) { 165 if (class_name == vmSymbols::java_lang_Class()) { 166 // mirror 167 ik = new (loader_data, size, THREAD) InstanceMirrorKlass(parser); 168 } 169 else if (is_class_loader(class_name, parser)) { 170 // class loader 171 ik = new (loader_data, size, THREAD) InstanceClassLoaderKlass(parser); 172 } 173 else { 174 // normal 175 ik = new (loader_data, size, THREAD) InstanceKlass(parser, InstanceKlass::_misc_kind_other); 176 } 177 } 178 else { 179 // reference 180 ik = new (loader_data, size, THREAD) InstanceRefKlass(parser); 181 } 182 183 // Check for pending exception before adding to the loader data and incrementing 184 // class count. Can get OOM here. 185 if (HAS_PENDING_EXCEPTION) { 186 return NULL; 187 } 188 189 assert(ik != NULL, "invariant"); 190 191 const bool publicize = !parser.is_internal(); 192 193 // Add all classes to our internal class loader list here, 194 // including classes in the bootstrap (NULL) class loader. 195 loader_data->add_class(ik, publicize); 196 Atomic::inc(&_total_instanceKlass_count); 197 198 return ik; 199 } 200 201 202 // copy method ordering from resource area to Metaspace 203 void InstanceKlass::copy_method_ordering(const intArray* m, TRAPS) { 204 if (m != NULL) { 205 // allocate a new array and copy contents (memcpy?) 206 _method_ordering = MetadataFactory::new_array<int>(class_loader_data(), m->length(), CHECK); 207 for (int i = 0; i < m->length(); i++) { 208 _method_ordering->at_put(i, m->at(i)); 209 } 210 } else { 211 _method_ordering = Universe::the_empty_int_array(); 212 } 213 } 214 215 // create a new array of vtable_indices for default methods 216 Array<int>* InstanceKlass::create_new_default_vtable_indices(int len, TRAPS) { 217 Array<int>* vtable_indices = MetadataFactory::new_array<int>(class_loader_data(), len, CHECK_NULL); 218 assert(default_vtable_indices() == NULL, "only create once"); 219 set_default_vtable_indices(vtable_indices); 220 return vtable_indices; 221 } 222 223 InstanceKlass::InstanceKlass(const ClassFileParser& parser, unsigned kind) : 224 _static_field_size(parser.static_field_size()), 225 _nonstatic_oop_map_size(nonstatic_oop_map_size(parser.total_oop_map_count())), 226 _itable_len(parser.itable_size()), 227 _reference_type(parser.reference_type()) { 228 set_vtable_length(parser.vtable_size()); 229 set_kind(kind); 230 set_access_flags(parser.access_flags()); 231 set_is_anonymous(parser.is_anonymous()); 232 set_layout_helper(Klass::instance_layout_helper(parser.layout_size(), 233 false)); 234 235 assert(NULL == _methods, "underlying memory not zeroed?"); 236 assert(is_instance_klass(), "is layout incorrect?"); 237 assert(size_helper() == parser.layout_size(), "incorrect size_helper?"); 238 } 239 240 void InstanceKlass::deallocate_methods(ClassLoaderData* loader_data, 241 Array<Method*>* methods) { 242 if (methods != NULL && methods != Universe::the_empty_method_array() && 243 !methods->is_shared()) { 244 for (int i = 0; i < methods->length(); i++) { 245 Method* method = methods->at(i); 246 if (method == NULL) continue; // maybe null if error processing 247 // Only want to delete methods that are not executing for RedefineClasses. 248 // The previous version will point to them so they're not totally dangling 249 assert (!method->on_stack(), "shouldn't be called with methods on stack"); 250 MetadataFactory::free_metadata(loader_data, method); 251 } 252 MetadataFactory::free_array<Method*>(loader_data, methods); 253 } 254 } 255 256 void InstanceKlass::deallocate_interfaces(ClassLoaderData* loader_data, 257 const Klass* super_klass, 258 Array<Klass*>* local_interfaces, 259 Array<Klass*>* transitive_interfaces) { 260 // Only deallocate transitive interfaces if not empty, same as super class 261 // or same as local interfaces. See code in parseClassFile. 262 Array<Klass*>* ti = transitive_interfaces; 263 if (ti != Universe::the_empty_klass_array() && ti != local_interfaces) { 264 // check that the interfaces don't come from super class 265 Array<Klass*>* sti = (super_klass == NULL) ? NULL : 266 InstanceKlass::cast(super_klass)->transitive_interfaces(); 267 if (ti != sti && ti != NULL && !ti->is_shared()) { 268 MetadataFactory::free_array<Klass*>(loader_data, ti); 269 } 270 } 271 272 // local interfaces can be empty 273 if (local_interfaces != Universe::the_empty_klass_array() && 274 local_interfaces != NULL && !local_interfaces->is_shared()) { 275 MetadataFactory::free_array<Klass*>(loader_data, local_interfaces); 276 } 277 } 278 279 // This function deallocates the metadata and C heap pointers that the 280 // InstanceKlass points to. 281 void InstanceKlass::deallocate_contents(ClassLoaderData* loader_data) { 282 283 // Orphan the mirror first, CMS thinks it's still live. 284 if (java_mirror() != NULL) { 285 java_lang_Class::set_klass(java_mirror(), NULL); 286 } 287 288 // Also remove mirror from handles 289 loader_data->remove_handle(_java_mirror); 290 291 // Need to take this class off the class loader data list. 292 loader_data->remove_class(this); 293 294 // The array_klass for this class is created later, after error handling. 295 // For class redefinition, we keep the original class so this scratch class 296 // doesn't have an array class. Either way, assert that there is nothing 297 // to deallocate. 298 assert(array_klasses() == NULL, "array classes shouldn't be created for this class yet"); 299 300 // Release C heap allocated data that this might point to, which includes 301 // reference counting symbol names. 302 release_C_heap_structures(); 303 304 deallocate_methods(loader_data, methods()); 305 set_methods(NULL); 306 307 if (method_ordering() != NULL && 308 method_ordering() != Universe::the_empty_int_array() && 309 !method_ordering()->is_shared()) { 310 MetadataFactory::free_array<int>(loader_data, method_ordering()); 311 } 312 set_method_ordering(NULL); 313 314 // default methods can be empty 315 if (default_methods() != NULL && 316 default_methods() != Universe::the_empty_method_array() && 317 !default_methods()->is_shared()) { 318 MetadataFactory::free_array<Method*>(loader_data, default_methods()); 319 } 320 // Do NOT deallocate the default methods, they are owned by superinterfaces. 321 set_default_methods(NULL); 322 323 // default methods vtable indices can be empty 324 if (default_vtable_indices() != NULL && 325 !default_vtable_indices()->is_shared()) { 326 MetadataFactory::free_array<int>(loader_data, default_vtable_indices()); 327 } 328 set_default_vtable_indices(NULL); 329 330 331 // This array is in Klass, but remove it with the InstanceKlass since 332 // this place would be the only caller and it can share memory with transitive 333 // interfaces. 334 if (secondary_supers() != NULL && 335 secondary_supers() != Universe::the_empty_klass_array() && 336 secondary_supers() != transitive_interfaces() && 337 !secondary_supers()->is_shared()) { 338 MetadataFactory::free_array<Klass*>(loader_data, secondary_supers()); 339 } 340 set_secondary_supers(NULL); 341 342 deallocate_interfaces(loader_data, super(), local_interfaces(), transitive_interfaces()); 343 set_transitive_interfaces(NULL); 344 set_local_interfaces(NULL); 345 346 if (fields() != NULL && !fields()->is_shared()) { 347 MetadataFactory::free_array<jushort>(loader_data, fields()); 348 } 349 set_fields(NULL, 0); 350 351 // If a method from a redefined class is using this constant pool, don't 352 // delete it, yet. The new class's previous version will point to this. 353 if (constants() != NULL) { 354 assert (!constants()->on_stack(), "shouldn't be called if anything is onstack"); 355 if (!constants()->is_shared()) { 356 MetadataFactory::free_metadata(loader_data, constants()); 357 } 358 // Delete any cached resolution errors for the constant pool 359 SystemDictionary::delete_resolution_error(constants()); 360 361 set_constants(NULL); 362 } 363 364 if (inner_classes() != NULL && 365 inner_classes() != Universe::the_empty_short_array() && 366 !inner_classes()->is_shared()) { 367 MetadataFactory::free_array<jushort>(loader_data, inner_classes()); 368 } 369 set_inner_classes(NULL); 370 371 // We should deallocate the Annotations instance if it's not in shared spaces. 372 if (annotations() != NULL && !annotations()->is_shared()) { 373 MetadataFactory::free_metadata(loader_data, annotations()); 374 } 375 set_annotations(NULL); 376 } 377 378 bool InstanceKlass::should_be_initialized() const { 379 return !is_initialized(); 380 } 381 382 klassItable InstanceKlass::itable() const { 383 return klassItable(const_cast<InstanceKlass*>(this)); 384 } 385 386 void InstanceKlass::eager_initialize(Thread *thread) { 387 if (!EagerInitialization) return; 388 389 if (this->is_not_initialized()) { 390 // abort if the the class has a class initializer 391 if (this->class_initializer() != NULL) return; 392 393 // abort if it is java.lang.Object (initialization is handled in genesis) 394 Klass* super_klass = super(); 395 if (super_klass == NULL) return; 396 397 // abort if the super class should be initialized 398 if (!InstanceKlass::cast(super_klass)->is_initialized()) return; 399 400 // call body to expose the this pointer 401 eager_initialize_impl(); 402 } 403 } 404 405 // JVMTI spec thinks there are signers and protection domain in the 406 // instanceKlass. These accessors pretend these fields are there. 407 // The hprof specification also thinks these fields are in InstanceKlass. 408 oop InstanceKlass::protection_domain() const { 409 // return the protection_domain from the mirror 410 return java_lang_Class::protection_domain(java_mirror()); 411 } 412 413 // To remove these from requires an incompatible change and CCC request. 414 objArrayOop InstanceKlass::signers() const { 415 // return the signers from the mirror 416 return java_lang_Class::signers(java_mirror()); 417 } 418 419 oop InstanceKlass::init_lock() const { 420 // return the init lock from the mirror 421 oop lock = java_lang_Class::init_lock(java_mirror()); 422 // Prevent reordering with any access of initialization state 423 OrderAccess::loadload(); 424 assert((oop)lock != NULL || !is_not_initialized(), // initialized or in_error state 425 "only fully initialized state can have a null lock"); 426 return lock; 427 } 428 429 // Set the initialization lock to null so the object can be GC'ed. Any racing 430 // threads to get this lock will see a null lock and will not lock. 431 // That's okay because they all check for initialized state after getting 432 // the lock and return. 433 void InstanceKlass::fence_and_clear_init_lock() { 434 // make sure previous stores are all done, notably the init_state. 435 OrderAccess::storestore(); 436 java_lang_Class::set_init_lock(java_mirror(), NULL); 437 assert(!is_not_initialized(), "class must be initialized now"); 438 } 439 440 void InstanceKlass::eager_initialize_impl() { 441 EXCEPTION_MARK; 442 HandleMark hm(THREAD); 443 Handle h_init_lock(THREAD, init_lock()); 444 ObjectLocker ol(h_init_lock, THREAD, h_init_lock() != NULL); 445 446 // abort if someone beat us to the initialization 447 if (!is_not_initialized()) return; // note: not equivalent to is_initialized() 448 449 ClassState old_state = init_state(); 450 link_class_impl(true, THREAD); 451 if (HAS_PENDING_EXCEPTION) { 452 CLEAR_PENDING_EXCEPTION; 453 // Abort if linking the class throws an exception. 454 455 // Use a test to avoid redundantly resetting the state if there's 456 // no change. Set_init_state() asserts that state changes make 457 // progress, whereas here we might just be spinning in place. 458 if (old_state != _init_state) 459 set_init_state(old_state); 460 } else { 461 // linking successfull, mark class as initialized 462 set_init_state(fully_initialized); 463 fence_and_clear_init_lock(); 464 // trace 465 if (log_is_enabled(Info, class, init)) { 466 ResourceMark rm(THREAD); 467 log_info(class, init)("[Initialized %s without side effects]", external_name()); 468 } 469 } 470 } 471 472 473 // See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization 474 // process. The step comments refers to the procedure described in that section. 475 // Note: implementation moved to static method to expose the this pointer. 476 void InstanceKlass::initialize(TRAPS) { 477 if (this->should_be_initialized()) { 478 initialize_impl(CHECK); 479 // Note: at this point the class may be initialized 480 // OR it may be in the state of being initialized 481 // in case of recursive initialization! 482 } else { 483 assert(is_initialized(), "sanity check"); 484 } 485 } 486 487 488 bool InstanceKlass::verify_code(bool throw_verifyerror, TRAPS) { 489 // 1) Verify the bytecodes 490 Verifier::Mode mode = 491 throw_verifyerror ? Verifier::ThrowException : Verifier::NoException; 492 return Verifier::verify(this, mode, should_verify_class(), THREAD); 493 } 494 495 496 // Used exclusively by the shared spaces dump mechanism to prevent 497 // classes mapped into the shared regions in new VMs from appearing linked. 498 499 void InstanceKlass::unlink_class() { 500 assert(is_linked(), "must be linked"); 501 _init_state = loaded; 502 } 503 504 void InstanceKlass::link_class(TRAPS) { 505 assert(is_loaded(), "must be loaded"); 506 if (!is_linked()) { 507 link_class_impl(true, CHECK); 508 } 509 } 510 511 // Called to verify that a class can link during initialization, without 512 // throwing a VerifyError. 513 bool InstanceKlass::link_class_or_fail(TRAPS) { 514 assert(is_loaded(), "must be loaded"); 515 if (!is_linked()) { 516 link_class_impl(false, CHECK_false); 517 } 518 return is_linked(); 519 } 520 521 bool InstanceKlass::link_class_impl(bool throw_verifyerror, TRAPS) { 522 if (DumpSharedSpaces && is_in_error_state()) { 523 // This is for CDS dumping phase only -- we use the in_error_state to indicate that 524 // the class has failed verification. Throwing the NoClassDefFoundError here is just 525 // a convenient way to stop repeat attempts to verify the same (bad) class. 526 // 527 // Note that the NoClassDefFoundError is not part of the JLS, and should not be thrown 528 // if we are executing Java code. This is not a problem for CDS dumping phase since 529 // it doesn't execute any Java code. 530 ResourceMark rm(THREAD); 531 Exceptions::fthrow(THREAD_AND_LOCATION, 532 vmSymbols::java_lang_NoClassDefFoundError(), 533 "Class %s, or one of its supertypes, failed class initialization", 534 external_name()); 535 return false; 536 } 537 // return if already verified 538 if (is_linked()) { 539 return true; 540 } 541 542 // Timing 543 // timer handles recursion 544 assert(THREAD->is_Java_thread(), "non-JavaThread in link_class_impl"); 545 JavaThread* jt = (JavaThread*)THREAD; 546 547 // link super class before linking this class 548 Klass* super_klass = super(); 549 if (super_klass != NULL) { 550 if (super_klass->is_interface()) { // check if super class is an interface 551 ResourceMark rm(THREAD); 552 Exceptions::fthrow( 553 THREAD_AND_LOCATION, 554 vmSymbols::java_lang_IncompatibleClassChangeError(), 555 "class %s has interface %s as super class", 556 external_name(), 557 super_klass->external_name() 558 ); 559 return false; 560 } 561 562 InstanceKlass* ik_super = InstanceKlass::cast(super_klass); 563 ik_super->link_class_impl(throw_verifyerror, CHECK_false); 564 } 565 566 // link all interfaces implemented by this class before linking this class 567 Array<Klass*>* interfaces = local_interfaces(); 568 int num_interfaces = interfaces->length(); 569 for (int index = 0; index < num_interfaces; index++) { 570 InstanceKlass* interk = InstanceKlass::cast(interfaces->at(index)); 571 interk->link_class_impl(throw_verifyerror, CHECK_false); 572 } 573 574 // in case the class is linked in the process of linking its superclasses 575 if (is_linked()) { 576 return true; 577 } 578 579 // trace only the link time for this klass that includes 580 // the verification time 581 PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(), 582 ClassLoader::perf_class_link_selftime(), 583 ClassLoader::perf_classes_linked(), 584 jt->get_thread_stat()->perf_recursion_counts_addr(), 585 jt->get_thread_stat()->perf_timers_addr(), 586 PerfClassTraceTime::CLASS_LINK); 587 588 // verification & rewriting 589 { 590 HandleMark hm(THREAD); 591 Handle h_init_lock(THREAD, init_lock()); 592 ObjectLocker ol(h_init_lock, THREAD, h_init_lock() != NULL); 593 // rewritten will have been set if loader constraint error found 594 // on an earlier link attempt 595 // don't verify or rewrite if already rewritten 596 // 597 598 if (!is_linked()) { 599 if (!is_rewritten()) { 600 { 601 bool verify_ok = verify_code(throw_verifyerror, THREAD); 602 if (!verify_ok) { 603 return false; 604 } 605 } 606 607 // Just in case a side-effect of verify linked this class already 608 // (which can sometimes happen since the verifier loads classes 609 // using custom class loaders, which are free to initialize things) 610 if (is_linked()) { 611 return true; 612 } 613 614 // also sets rewritten 615 rewrite_class(CHECK_false); 616 } else if (is_shared()) { 617 SystemDictionaryShared::check_verification_constraints(this, CHECK_false); 618 } 619 620 // relocate jsrs and link methods after they are all rewritten 621 link_methods(CHECK_false); 622 623 // Initialize the vtable and interface table after 624 // methods have been rewritten since rewrite may 625 // fabricate new Method*s. 626 // also does loader constraint checking 627 // 628 // initialize_vtable and initialize_itable need to be rerun for 629 // a shared class if the class is not loaded by the NULL classloader. 630 ClassLoaderData * loader_data = class_loader_data(); 631 if (!(is_shared() && 632 loader_data->is_the_null_class_loader_data())) { 633 ResourceMark rm(THREAD); 634 vtable().initialize_vtable(true, CHECK_false); 635 itable().initialize_itable(true, CHECK_false); 636 } 637 #ifdef ASSERT 638 else { 639 vtable().verify(tty, true); 640 // In case itable verification is ever added. 641 // itable().verify(tty, true); 642 } 643 #endif 644 set_init_state(linked); 645 if (JvmtiExport::should_post_class_prepare()) { 646 Thread *thread = THREAD; 647 assert(thread->is_Java_thread(), "thread->is_Java_thread()"); 648 JvmtiExport::post_class_prepare((JavaThread *) thread, this); 649 } 650 } 651 } 652 return true; 653 } 654 655 656 // Rewrite the byte codes of all of the methods of a class. 657 // The rewriter must be called exactly once. Rewriting must happen after 658 // verification but before the first method of the class is executed. 659 void InstanceKlass::rewrite_class(TRAPS) { 660 assert(is_loaded(), "must be loaded"); 661 if (is_rewritten()) { 662 assert(is_shared(), "rewriting an unshared class?"); 663 return; 664 } 665 Rewriter::rewrite(this, CHECK); 666 set_rewritten(); 667 } 668 669 // Now relocate and link method entry points after class is rewritten. 670 // This is outside is_rewritten flag. In case of an exception, it can be 671 // executed more than once. 672 void InstanceKlass::link_methods(TRAPS) { 673 int len = methods()->length(); 674 for (int i = len-1; i >= 0; i--) { 675 methodHandle m(THREAD, methods()->at(i)); 676 677 // Set up method entry points for compiler and interpreter . 678 m->link_method(m, CHECK); 679 } 680 } 681 682 // Eagerly initialize superinterfaces that declare default methods (concrete instance: any access) 683 void InstanceKlass::initialize_super_interfaces(TRAPS) { 684 assert (has_nonstatic_concrete_methods(), "caller should have checked this"); 685 for (int i = 0; i < local_interfaces()->length(); ++i) { 686 Klass* iface = local_interfaces()->at(i); 687 InstanceKlass* ik = InstanceKlass::cast(iface); 688 689 // Initialization is depth first search ie. we start with top of the inheritance tree 690 // has_nonstatic_concrete_methods drives searching superinterfaces since it 691 // means has_nonstatic_concrete_methods in its superinterface hierarchy 692 if (ik->has_nonstatic_concrete_methods()) { 693 ik->initialize_super_interfaces(CHECK); 694 } 695 696 // Only initialize() interfaces that "declare" concrete methods. 697 if (ik->should_be_initialized() && ik->declares_nonstatic_concrete_methods()) { 698 ik->initialize(CHECK); 699 } 700 } 701 } 702 703 void InstanceKlass::initialize_impl(TRAPS) { 704 HandleMark hm(THREAD); 705 706 // Make sure klass is linked (verified) before initialization 707 // A class could already be verified, since it has been reflected upon. 708 link_class(CHECK); 709 710 DTRACE_CLASSINIT_PROBE(required, -1); 711 712 bool wait = false; 713 714 // refer to the JVM book page 47 for description of steps 715 // Step 1 716 { 717 Handle h_init_lock(THREAD, init_lock()); 718 ObjectLocker ol(h_init_lock, THREAD, h_init_lock() != NULL); 719 720 Thread *self = THREAD; // it's passed the current thread 721 722 // Step 2 723 // If we were to use wait() instead of waitInterruptibly() then 724 // we might end up throwing IE from link/symbol resolution sites 725 // that aren't expected to throw. This would wreak havoc. See 6320309. 726 while(is_being_initialized() && !is_reentrant_initialization(self)) { 727 wait = true; 728 ol.waitUninterruptibly(CHECK); 729 } 730 731 // Step 3 732 if (is_being_initialized() && is_reentrant_initialization(self)) { 733 DTRACE_CLASSINIT_PROBE_WAIT(recursive, -1, wait); 734 return; 735 } 736 737 // Step 4 738 if (is_initialized()) { 739 DTRACE_CLASSINIT_PROBE_WAIT(concurrent, -1, wait); 740 return; 741 } 742 743 // Step 5 744 if (is_in_error_state()) { 745 DTRACE_CLASSINIT_PROBE_WAIT(erroneous, -1, wait); 746 ResourceMark rm(THREAD); 747 const char* desc = "Could not initialize class "; 748 const char* className = external_name(); 749 size_t msglen = strlen(desc) + strlen(className) + 1; 750 char* message = NEW_RESOURCE_ARRAY(char, msglen); 751 if (NULL == message) { 752 // Out of memory: can't create detailed error message 753 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), className); 754 } else { 755 jio_snprintf(message, msglen, "%s%s", desc, className); 756 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), message); 757 } 758 } 759 760 // Step 6 761 set_init_state(being_initialized); 762 set_init_thread(self); 763 } 764 765 // Step 7 766 // Next, if C is a class rather than an interface, initialize it's super class and super 767 // interfaces. 768 if (!is_interface()) { 769 Klass* super_klass = super(); 770 if (super_klass != NULL && super_klass->should_be_initialized()) { 771 super_klass->initialize(THREAD); 772 } 773 // If C implements any interface that declares a non-static, concrete method, 774 // the initialization of C triggers initialization of its super interfaces. 775 // Only need to recurse if has_nonstatic_concrete_methods which includes declaring and 776 // having a superinterface that declares, non-static, concrete methods 777 if (!HAS_PENDING_EXCEPTION && has_nonstatic_concrete_methods()) { 778 initialize_super_interfaces(THREAD); 779 } 780 781 // If any exceptions, complete abruptly, throwing the same exception as above. 782 if (HAS_PENDING_EXCEPTION) { 783 Handle e(THREAD, PENDING_EXCEPTION); 784 CLEAR_PENDING_EXCEPTION; 785 { 786 EXCEPTION_MARK; 787 // Locks object, set state, and notify all waiting threads 788 set_initialization_state_and_notify(initialization_error, THREAD); 789 CLEAR_PENDING_EXCEPTION; 790 } 791 DTRACE_CLASSINIT_PROBE_WAIT(super__failed, -1, wait); 792 THROW_OOP(e()); 793 } 794 } 795 796 797 // Look for aot compiled methods for this klass, including class initializer. 798 AOTLoader::load_for_klass(this, THREAD); 799 800 // Step 8 801 { 802 assert(THREAD->is_Java_thread(), "non-JavaThread in initialize_impl"); 803 JavaThread* jt = (JavaThread*)THREAD; 804 DTRACE_CLASSINIT_PROBE_WAIT(clinit, -1, wait); 805 // Timer includes any side effects of class initialization (resolution, 806 // etc), but not recursive entry into call_class_initializer(). 807 PerfClassTraceTime timer(ClassLoader::perf_class_init_time(), 808 ClassLoader::perf_class_init_selftime(), 809 ClassLoader::perf_classes_inited(), 810 jt->get_thread_stat()->perf_recursion_counts_addr(), 811 jt->get_thread_stat()->perf_timers_addr(), 812 PerfClassTraceTime::CLASS_CLINIT); 813 call_class_initializer(THREAD); 814 } 815 816 // Step 9 817 if (!HAS_PENDING_EXCEPTION) { 818 set_initialization_state_and_notify(fully_initialized, CHECK); 819 { 820 debug_only(vtable().verify(tty, true);) 821 } 822 } 823 else { 824 // Step 10 and 11 825 Handle e(THREAD, PENDING_EXCEPTION); 826 CLEAR_PENDING_EXCEPTION; 827 // JVMTI has already reported the pending exception 828 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError 829 JvmtiExport::clear_detected_exception((JavaThread*)THREAD); 830 { 831 EXCEPTION_MARK; 832 set_initialization_state_and_notify(initialization_error, THREAD); 833 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, class initialization error is thrown below 834 // JVMTI has already reported the pending exception 835 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError 836 JvmtiExport::clear_detected_exception((JavaThread*)THREAD); 837 } 838 DTRACE_CLASSINIT_PROBE_WAIT(error, -1, wait); 839 if (e->is_a(SystemDictionary::Error_klass())) { 840 THROW_OOP(e()); 841 } else { 842 JavaCallArguments args(e); 843 THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(), 844 vmSymbols::throwable_void_signature(), 845 &args); 846 } 847 } 848 DTRACE_CLASSINIT_PROBE_WAIT(end, -1, wait); 849 } 850 851 852 void InstanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) { 853 Handle h_init_lock(THREAD, init_lock()); 854 if (h_init_lock() != NULL) { 855 ObjectLocker ol(h_init_lock, THREAD); 856 set_init_state(state); 857 fence_and_clear_init_lock(); 858 ol.notify_all(CHECK); 859 } else { 860 assert(h_init_lock() != NULL, "The initialization state should never be set twice"); 861 set_init_state(state); 862 } 863 } 864 865 // The embedded _implementor field can only record one implementor. 866 // When there are more than one implementors, the _implementor field 867 // is set to the interface Klass* itself. Following are the possible 868 // values for the _implementor field: 869 // NULL - no implementor 870 // implementor Klass* - one implementor 871 // self - more than one implementor 872 // 873 // The _implementor field only exists for interfaces. 874 void InstanceKlass::add_implementor(Klass* k) { 875 assert(Compile_lock->owned_by_self(), ""); 876 assert(is_interface(), "not interface"); 877 // Filter out my subinterfaces. 878 // (Note: Interfaces are never on the subklass list.) 879 if (InstanceKlass::cast(k)->is_interface()) return; 880 881 // Filter out subclasses whose supers already implement me. 882 // (Note: CHA must walk subclasses of direct implementors 883 // in order to locate indirect implementors.) 884 Klass* sk = k->super(); 885 if (sk != NULL && InstanceKlass::cast(sk)->implements_interface(this)) 886 // We only need to check one immediate superclass, since the 887 // implements_interface query looks at transitive_interfaces. 888 // Any supers of the super have the same (or fewer) transitive_interfaces. 889 return; 890 891 Klass* ik = implementor(); 892 if (ik == NULL) { 893 set_implementor(k); 894 } else if (ik != this) { 895 // There is already an implementor. Use itself as an indicator of 896 // more than one implementors. 897 set_implementor(this); 898 } 899 900 // The implementor also implements the transitive_interfaces 901 for (int index = 0; index < local_interfaces()->length(); index++) { 902 InstanceKlass::cast(local_interfaces()->at(index))->add_implementor(k); 903 } 904 } 905 906 void InstanceKlass::init_implementor() { 907 if (is_interface()) { 908 set_implementor(NULL); 909 } 910 } 911 912 913 void InstanceKlass::process_interfaces(Thread *thread) { 914 // link this class into the implementors list of every interface it implements 915 for (int i = local_interfaces()->length() - 1; i >= 0; i--) { 916 assert(local_interfaces()->at(i)->is_klass(), "must be a klass"); 917 InstanceKlass* interf = InstanceKlass::cast(local_interfaces()->at(i)); 918 assert(interf->is_interface(), "expected interface"); 919 interf->add_implementor(this); 920 } 921 } 922 923 bool InstanceKlass::can_be_primary_super_slow() const { 924 if (is_interface()) 925 return false; 926 else 927 return Klass::can_be_primary_super_slow(); 928 } 929 930 GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots) { 931 // The secondaries are the implemented interfaces. 932 Array<Klass*>* interfaces = transitive_interfaces(); 933 int num_secondaries = num_extra_slots + interfaces->length(); 934 if (num_secondaries == 0) { 935 // Must share this for correct bootstrapping! 936 set_secondary_supers(Universe::the_empty_klass_array()); 937 return NULL; 938 } else if (num_extra_slots == 0) { 939 // The secondary super list is exactly the same as the transitive interfaces. 940 // Redefine classes has to be careful not to delete this! 941 set_secondary_supers(interfaces); 942 return NULL; 943 } else { 944 // Copy transitive interfaces to a temporary growable array to be constructed 945 // into the secondary super list with extra slots. 946 GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length()); 947 for (int i = 0; i < interfaces->length(); i++) { 948 secondaries->push(interfaces->at(i)); 949 } 950 return secondaries; 951 } 952 } 953 954 bool InstanceKlass::compute_is_subtype_of(Klass* k) { 955 if (k->is_interface()) { 956 return implements_interface(k); 957 } else { 958 return Klass::compute_is_subtype_of(k); 959 } 960 } 961 962 bool InstanceKlass::implements_interface(Klass* k) const { 963 if (this == k) return true; 964 assert(k->is_interface(), "should be an interface class"); 965 for (int i = 0; i < transitive_interfaces()->length(); i++) { 966 if (transitive_interfaces()->at(i) == k) { 967 return true; 968 } 969 } 970 return false; 971 } 972 973 bool InstanceKlass::is_same_or_direct_interface(Klass *k) const { 974 // Verify direct super interface 975 if (this == k) return true; 976 assert(k->is_interface(), "should be an interface class"); 977 for (int i = 0; i < local_interfaces()->length(); i++) { 978 if (local_interfaces()->at(i) == k) { 979 return true; 980 } 981 } 982 return false; 983 } 984 985 objArrayOop InstanceKlass::allocate_objArray(int n, int length, TRAPS) { 986 if (length < 0) THROW_0(vmSymbols::java_lang_NegativeArraySizeException()); 987 if (length > arrayOopDesc::max_array_length(T_OBJECT)) { 988 report_java_out_of_memory("Requested array size exceeds VM limit"); 989 JvmtiExport::post_array_size_exhausted(); 990 THROW_OOP_0(Universe::out_of_memory_error_array_size()); 991 } 992 int size = objArrayOopDesc::object_size(length); 993 Klass* ak = array_klass(n, CHECK_NULL); 994 objArrayOop o = 995 (objArrayOop)CollectedHeap::array_allocate(ak, size, length, CHECK_NULL); 996 return o; 997 } 998 999 instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) { 1000 if (TraceFinalizerRegistration) { 1001 tty->print("Registered "); 1002 i->print_value_on(tty); 1003 tty->print_cr(" (" INTPTR_FORMAT ") as finalizable", p2i(i)); 1004 } 1005 instanceHandle h_i(THREAD, i); 1006 // Pass the handle as argument, JavaCalls::call expects oop as jobjects 1007 JavaValue result(T_VOID); 1008 JavaCallArguments args(h_i); 1009 methodHandle mh (THREAD, Universe::finalizer_register_method()); 1010 JavaCalls::call(&result, mh, &args, CHECK_NULL); 1011 return h_i(); 1012 } 1013 1014 instanceOop InstanceKlass::allocate_instance(TRAPS) { 1015 bool has_finalizer_flag = has_finalizer(); // Query before possible GC 1016 int size = size_helper(); // Query before forming handle. 1017 1018 instanceOop i; 1019 1020 i = (instanceOop)CollectedHeap::obj_allocate(this, size, CHECK_NULL); 1021 if (has_finalizer_flag && !RegisterFinalizersAtInit) { 1022 i = register_finalizer(i, CHECK_NULL); 1023 } 1024 return i; 1025 } 1026 1027 void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) { 1028 if (is_interface() || is_abstract()) { 1029 ResourceMark rm(THREAD); 1030 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError() 1031 : vmSymbols::java_lang_InstantiationException(), external_name()); 1032 } 1033 if (this == SystemDictionary::Class_klass()) { 1034 ResourceMark rm(THREAD); 1035 THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError() 1036 : vmSymbols::java_lang_IllegalAccessException(), external_name()); 1037 } 1038 } 1039 1040 Klass* InstanceKlass::array_klass_impl(bool or_null, int n, TRAPS) { 1041 // Need load-acquire for lock-free read 1042 if (array_klasses_acquire() == NULL) { 1043 if (or_null) return NULL; 1044 1045 ResourceMark rm; 1046 JavaThread *jt = (JavaThread *)THREAD; 1047 { 1048 // Atomic creation of array_klasses 1049 MutexLocker mc(Compile_lock, THREAD); // for vtables 1050 MutexLocker ma(MultiArray_lock, THREAD); 1051 1052 // Check if update has already taken place 1053 if (array_klasses() == NULL) { 1054 Klass* k = ObjArrayKlass::allocate_objArray_klass(class_loader_data(), 1, this, CHECK_NULL); 1055 // use 'release' to pair with lock-free load 1056 release_set_array_klasses(k); 1057 } 1058 } 1059 } 1060 // _this will always be set at this point 1061 ObjArrayKlass* oak = (ObjArrayKlass*)array_klasses(); 1062 if (or_null) { 1063 return oak->array_klass_or_null(n); 1064 } 1065 return oak->array_klass(n, THREAD); 1066 } 1067 1068 Klass* InstanceKlass::array_klass_impl(bool or_null, TRAPS) { 1069 return array_klass_impl(or_null, 1, THREAD); 1070 } 1071 1072 static int call_class_initializer_counter = 0; // for debugging 1073 1074 Method* InstanceKlass::class_initializer() const { 1075 Method* clinit = find_method( 1076 vmSymbols::class_initializer_name(), vmSymbols::void_method_signature()); 1077 if (clinit != NULL && clinit->has_valid_initializer_flags()) { 1078 return clinit; 1079 } 1080 return NULL; 1081 } 1082 1083 void InstanceKlass::call_class_initializer(TRAPS) { 1084 if (ReplayCompiles && 1085 (ReplaySuppressInitializers == 1 || 1086 (ReplaySuppressInitializers >= 2 && class_loader() != NULL))) { 1087 // Hide the existence of the initializer for the purpose of replaying the compile 1088 return; 1089 } 1090 1091 methodHandle h_method(THREAD, class_initializer()); 1092 assert(!is_initialized(), "we cannot initialize twice"); 1093 LogTarget(Info, class, init) lt; 1094 if (lt.is_enabled()) { 1095 ResourceMark rm; 1096 LogStream ls(lt); 1097 ls.print("%d Initializing ", call_class_initializer_counter++); 1098 name()->print_value_on(&ls); 1099 ls.print_cr("%s (" INTPTR_FORMAT ")", h_method() == NULL ? "(no method)" : "", p2i(this)); 1100 } 1101 if (h_method() != NULL) { 1102 JavaCallArguments args; // No arguments 1103 JavaValue result(T_VOID); 1104 JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args) 1105 } 1106 } 1107 1108 1109 void InstanceKlass::mask_for(const methodHandle& method, int bci, 1110 InterpreterOopMap* entry_for) { 1111 // Lazily create the _oop_map_cache at first request 1112 // Lock-free access requires load_ptr_acquire. 1113 OopMapCache* oop_map_cache = 1114 static_cast<OopMapCache*>(OrderAccess::load_ptr_acquire(&_oop_map_cache)); 1115 if (oop_map_cache == NULL) { 1116 MutexLocker x(OopMapCacheAlloc_lock); 1117 // Check if _oop_map_cache was allocated while we were waiting for this lock 1118 if ((oop_map_cache = _oop_map_cache) == NULL) { 1119 oop_map_cache = new OopMapCache(); 1120 // Ensure _oop_map_cache is stable, since it is examined without a lock 1121 OrderAccess::release_store_ptr(&_oop_map_cache, oop_map_cache); 1122 } 1123 } 1124 // _oop_map_cache is constant after init; lookup below does its own locking. 1125 oop_map_cache->lookup(method, bci, entry_for); 1126 } 1127 1128 1129 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const { 1130 for (JavaFieldStream fs(this); !fs.done(); fs.next()) { 1131 Symbol* f_name = fs.name(); 1132 Symbol* f_sig = fs.signature(); 1133 if (f_name == name && f_sig == sig) { 1134 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index()); 1135 return true; 1136 } 1137 } 1138 return false; 1139 } 1140 1141 1142 Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const { 1143 const int n = local_interfaces()->length(); 1144 for (int i = 0; i < n; i++) { 1145 Klass* intf1 = local_interfaces()->at(i); 1146 assert(intf1->is_interface(), "just checking type"); 1147 // search for field in current interface 1148 if (InstanceKlass::cast(intf1)->find_local_field(name, sig, fd)) { 1149 assert(fd->is_static(), "interface field must be static"); 1150 return intf1; 1151 } 1152 // search for field in direct superinterfaces 1153 Klass* intf2 = InstanceKlass::cast(intf1)->find_interface_field(name, sig, fd); 1154 if (intf2 != NULL) return intf2; 1155 } 1156 // otherwise field lookup fails 1157 return NULL; 1158 } 1159 1160 1161 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const { 1162 // search order according to newest JVM spec (5.4.3.2, p.167). 1163 // 1) search for field in current klass 1164 if (find_local_field(name, sig, fd)) { 1165 return const_cast<InstanceKlass*>(this); 1166 } 1167 // 2) search for field recursively in direct superinterfaces 1168 { Klass* intf = find_interface_field(name, sig, fd); 1169 if (intf != NULL) return intf; 1170 } 1171 // 3) apply field lookup recursively if superclass exists 1172 { Klass* supr = super(); 1173 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, fd); 1174 } 1175 // 4) otherwise field lookup fails 1176 return NULL; 1177 } 1178 1179 1180 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const { 1181 // search order according to newest JVM spec (5.4.3.2, p.167). 1182 // 1) search for field in current klass 1183 if (find_local_field(name, sig, fd)) { 1184 if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this); 1185 } 1186 // 2) search for field recursively in direct superinterfaces 1187 if (is_static) { 1188 Klass* intf = find_interface_field(name, sig, fd); 1189 if (intf != NULL) return intf; 1190 } 1191 // 3) apply field lookup recursively if superclass exists 1192 { Klass* supr = super(); 1193 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, is_static, fd); 1194 } 1195 // 4) otherwise field lookup fails 1196 return NULL; 1197 } 1198 1199 1200 bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const { 1201 for (JavaFieldStream fs(this); !fs.done(); fs.next()) { 1202 if (fs.offset() == offset) { 1203 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index()); 1204 if (fd->is_static() == is_static) return true; 1205 } 1206 } 1207 return false; 1208 } 1209 1210 1211 bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const { 1212 Klass* klass = const_cast<InstanceKlass*>(this); 1213 while (klass != NULL) { 1214 if (InstanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) { 1215 return true; 1216 } 1217 klass = klass->super(); 1218 } 1219 return false; 1220 } 1221 1222 1223 void InstanceKlass::methods_do(void f(Method* method)) { 1224 // Methods aren't stable until they are loaded. This can be read outside 1225 // a lock through the ClassLoaderData for profiling 1226 if (!is_loaded()) { 1227 return; 1228 } 1229 1230 int len = methods()->length(); 1231 for (int index = 0; index < len; index++) { 1232 Method* m = methods()->at(index); 1233 assert(m->is_method(), "must be method"); 1234 f(m); 1235 } 1236 } 1237 1238 1239 void InstanceKlass::do_local_static_fields(FieldClosure* cl) { 1240 for (JavaFieldStream fs(this); !fs.done(); fs.next()) { 1241 if (fs.access_flags().is_static()) { 1242 fieldDescriptor& fd = fs.field_descriptor(); 1243 cl->do_field(&fd); 1244 } 1245 } 1246 } 1247 1248 1249 void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle mirror, TRAPS) { 1250 for (JavaFieldStream fs(this); !fs.done(); fs.next()) { 1251 if (fs.access_flags().is_static()) { 1252 fieldDescriptor& fd = fs.field_descriptor(); 1253 f(&fd, mirror, CHECK); 1254 } 1255 } 1256 } 1257 1258 1259 static int compare_fields_by_offset(int* a, int* b) { 1260 return a[0] - b[0]; 1261 } 1262 1263 void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) { 1264 InstanceKlass* super = superklass(); 1265 if (super != NULL) { 1266 super->do_nonstatic_fields(cl); 1267 } 1268 fieldDescriptor fd; 1269 int length = java_fields_count(); 1270 // In DebugInfo nonstatic fields are sorted by offset. 1271 int* fields_sorted = NEW_C_HEAP_ARRAY(int, 2*(length+1), mtClass); 1272 int j = 0; 1273 for (int i = 0; i < length; i += 1) { 1274 fd.reinitialize(this, i); 1275 if (!fd.is_static()) { 1276 fields_sorted[j + 0] = fd.offset(); 1277 fields_sorted[j + 1] = i; 1278 j += 2; 1279 } 1280 } 1281 if (j > 0) { 1282 length = j; 1283 // _sort_Fn is defined in growableArray.hpp. 1284 qsort(fields_sorted, length/2, 2*sizeof(int), (_sort_Fn)compare_fields_by_offset); 1285 for (int i = 0; i < length; i += 2) { 1286 fd.reinitialize(this, fields_sorted[i + 1]); 1287 assert(!fd.is_static() && fd.offset() == fields_sorted[i], "only nonstatic fields"); 1288 cl->do_field(&fd); 1289 } 1290 } 1291 FREE_C_HEAP_ARRAY(int, fields_sorted); 1292 } 1293 1294 1295 void InstanceKlass::array_klasses_do(void f(Klass* k, TRAPS), TRAPS) { 1296 if (array_klasses() != NULL) 1297 ArrayKlass::cast(array_klasses())->array_klasses_do(f, THREAD); 1298 } 1299 1300 void InstanceKlass::array_klasses_do(void f(Klass* k)) { 1301 if (array_klasses() != NULL) 1302 ArrayKlass::cast(array_klasses())->array_klasses_do(f); 1303 } 1304 1305 #ifdef ASSERT 1306 static int linear_search(const Array<Method*>* methods, 1307 const Symbol* name, 1308 const Symbol* signature) { 1309 const int len = methods->length(); 1310 for (int index = 0; index < len; index++) { 1311 const Method* const m = methods->at(index); 1312 assert(m->is_method(), "must be method"); 1313 if (m->signature() == signature && m->name() == name) { 1314 return index; 1315 } 1316 } 1317 return -1; 1318 } 1319 #endif 1320 1321 static int binary_search(const Array<Method*>* methods, const Symbol* name) { 1322 int len = methods->length(); 1323 // methods are sorted, so do binary search 1324 int l = 0; 1325 int h = len - 1; 1326 while (l <= h) { 1327 int mid = (l + h) >> 1; 1328 Method* m = methods->at(mid); 1329 assert(m->is_method(), "must be method"); 1330 int res = m->name()->fast_compare(name); 1331 if (res == 0) { 1332 return mid; 1333 } else if (res < 0) { 1334 l = mid + 1; 1335 } else { 1336 h = mid - 1; 1337 } 1338 } 1339 return -1; 1340 } 1341 1342 // find_method looks up the name/signature in the local methods array 1343 Method* InstanceKlass::find_method(const Symbol* name, 1344 const Symbol* signature) const { 1345 return find_method_impl(name, signature, find_overpass, find_static, find_private); 1346 } 1347 1348 Method* InstanceKlass::find_method_impl(const Symbol* name, 1349 const Symbol* signature, 1350 OverpassLookupMode overpass_mode, 1351 StaticLookupMode static_mode, 1352 PrivateLookupMode private_mode) const { 1353 return InstanceKlass::find_method_impl(methods(), 1354 name, 1355 signature, 1356 overpass_mode, 1357 static_mode, 1358 private_mode); 1359 } 1360 1361 // find_instance_method looks up the name/signature in the local methods array 1362 // and skips over static methods 1363 Method* InstanceKlass::find_instance_method(const Array<Method*>* methods, 1364 const Symbol* name, 1365 const Symbol* signature) { 1366 Method* const meth = InstanceKlass::find_method_impl(methods, 1367 name, 1368 signature, 1369 find_overpass, 1370 skip_static, 1371 find_private); 1372 assert(((meth == NULL) || !meth->is_static()), 1373 "find_instance_method should have skipped statics"); 1374 return meth; 1375 } 1376 1377 // find_instance_method looks up the name/signature in the local methods array 1378 // and skips over static methods 1379 Method* InstanceKlass::find_instance_method(const Symbol* name, const Symbol* signature) const { 1380 return InstanceKlass::find_instance_method(methods(), name, signature); 1381 } 1382 1383 // Find looks up the name/signature in the local methods array 1384 // and filters on the overpass, static and private flags 1385 // This returns the first one found 1386 // note that the local methods array can have up to one overpass, one static 1387 // and one instance (private or not) with the same name/signature 1388 Method* InstanceKlass::find_local_method(const Symbol* name, 1389 const Symbol* signature, 1390 OverpassLookupMode overpass_mode, 1391 StaticLookupMode static_mode, 1392 PrivateLookupMode private_mode) const { 1393 return InstanceKlass::find_method_impl(methods(), 1394 name, 1395 signature, 1396 overpass_mode, 1397 static_mode, 1398 private_mode); 1399 } 1400 1401 // Find looks up the name/signature in the local methods array 1402 // and filters on the overpass, static and private flags 1403 // This returns the first one found 1404 // note that the local methods array can have up to one overpass, one static 1405 // and one instance (private or not) with the same name/signature 1406 Method* InstanceKlass::find_local_method(const Array<Method*>* methods, 1407 const Symbol* name, 1408 const Symbol* signature, 1409 OverpassLookupMode overpass_mode, 1410 StaticLookupMode static_mode, 1411 PrivateLookupMode private_mode) { 1412 return InstanceKlass::find_method_impl(methods, 1413 name, 1414 signature, 1415 overpass_mode, 1416 static_mode, 1417 private_mode); 1418 } 1419 1420 Method* InstanceKlass::find_method(const Array<Method*>* methods, 1421 const Symbol* name, 1422 const Symbol* signature) { 1423 return InstanceKlass::find_method_impl(methods, 1424 name, 1425 signature, 1426 find_overpass, 1427 find_static, 1428 find_private); 1429 } 1430 1431 Method* InstanceKlass::find_method_impl(const Array<Method*>* methods, 1432 const Symbol* name, 1433 const Symbol* signature, 1434 OverpassLookupMode overpass_mode, 1435 StaticLookupMode static_mode, 1436 PrivateLookupMode private_mode) { 1437 int hit = find_method_index(methods, name, signature, overpass_mode, static_mode, private_mode); 1438 return hit >= 0 ? methods->at(hit): NULL; 1439 } 1440 1441 // true if method matches signature and conforms to skipping_X conditions. 1442 static bool method_matches(const Method* m, 1443 const Symbol* signature, 1444 bool skipping_overpass, 1445 bool skipping_static, 1446 bool skipping_private) { 1447 return ((m->signature() == signature) && 1448 (!skipping_overpass || !m->is_overpass()) && 1449 (!skipping_static || !m->is_static()) && 1450 (!skipping_private || !m->is_private())); 1451 } 1452 1453 // Used directly for default_methods to find the index into the 1454 // default_vtable_indices, and indirectly by find_method 1455 // find_method_index looks in the local methods array to return the index 1456 // of the matching name/signature. If, overpass methods are being ignored, 1457 // the search continues to find a potential non-overpass match. This capability 1458 // is important during method resolution to prefer a static method, for example, 1459 // over an overpass method. 1460 // There is the possibility in any _method's array to have the same name/signature 1461 // for a static method, an overpass method and a local instance method 1462 // To correctly catch a given method, the search criteria may need 1463 // to explicitly skip the other two. For local instance methods, it 1464 // is often necessary to skip private methods 1465 int InstanceKlass::find_method_index(const Array<Method*>* methods, 1466 const Symbol* name, 1467 const Symbol* signature, 1468 OverpassLookupMode overpass_mode, 1469 StaticLookupMode static_mode, 1470 PrivateLookupMode private_mode) { 1471 const bool skipping_overpass = (overpass_mode == skip_overpass); 1472 const bool skipping_static = (static_mode == skip_static); 1473 const bool skipping_private = (private_mode == skip_private); 1474 const int hit = binary_search(methods, name); 1475 if (hit != -1) { 1476 const Method* const m = methods->at(hit); 1477 1478 // Do linear search to find matching signature. First, quick check 1479 // for common case, ignoring overpasses if requested. 1480 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) { 1481 return hit; 1482 } 1483 1484 // search downwards through overloaded methods 1485 int i; 1486 for (i = hit - 1; i >= 0; --i) { 1487 const Method* const m = methods->at(i); 1488 assert(m->is_method(), "must be method"); 1489 if (m->name() != name) { 1490 break; 1491 } 1492 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) { 1493 return i; 1494 } 1495 } 1496 // search upwards 1497 for (i = hit + 1; i < methods->length(); ++i) { 1498 const Method* const m = methods->at(i); 1499 assert(m->is_method(), "must be method"); 1500 if (m->name() != name) { 1501 break; 1502 } 1503 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) { 1504 return i; 1505 } 1506 } 1507 // not found 1508 #ifdef ASSERT 1509 const int index = (skipping_overpass || skipping_static || skipping_private) ? -1 : 1510 linear_search(methods, name, signature); 1511 assert(-1 == index, "binary search should have found entry %d", index); 1512 #endif 1513 } 1514 return -1; 1515 } 1516 1517 int InstanceKlass::find_method_by_name(const Symbol* name, int* end) const { 1518 return find_method_by_name(methods(), name, end); 1519 } 1520 1521 int InstanceKlass::find_method_by_name(const Array<Method*>* methods, 1522 const Symbol* name, 1523 int* end_ptr) { 1524 assert(end_ptr != NULL, "just checking"); 1525 int start = binary_search(methods, name); 1526 int end = start + 1; 1527 if (start != -1) { 1528 while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start; 1529 while (end < methods->length() && (methods->at(end))->name() == name) ++end; 1530 *end_ptr = end; 1531 return start; 1532 } 1533 return -1; 1534 } 1535 1536 // uncached_lookup_method searches both the local class methods array and all 1537 // superclasses methods arrays, skipping any overpass methods in superclasses. 1538 Method* InstanceKlass::uncached_lookup_method(const Symbol* name, 1539 const Symbol* signature, 1540 OverpassLookupMode overpass_mode) const { 1541 OverpassLookupMode overpass_local_mode = overpass_mode; 1542 const Klass* klass = this; 1543 while (klass != NULL) { 1544 Method* const method = InstanceKlass::cast(klass)->find_method_impl(name, 1545 signature, 1546 overpass_local_mode, 1547 find_static, 1548 find_private); 1549 if (method != NULL) { 1550 return method; 1551 } 1552 klass = klass->super(); 1553 overpass_local_mode = skip_overpass; // Always ignore overpass methods in superclasses 1554 } 1555 return NULL; 1556 } 1557 1558 #ifdef ASSERT 1559 // search through class hierarchy and return true if this class or 1560 // one of the superclasses was redefined 1561 bool InstanceKlass::has_redefined_this_or_super() const { 1562 const Klass* klass = this; 1563 while (klass != NULL) { 1564 if (InstanceKlass::cast(klass)->has_been_redefined()) { 1565 return true; 1566 } 1567 klass = klass->super(); 1568 } 1569 return false; 1570 } 1571 #endif 1572 1573 // lookup a method in the default methods list then in all transitive interfaces 1574 // Do NOT return private or static methods 1575 Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name, 1576 Symbol* signature) const { 1577 Method* m = NULL; 1578 if (default_methods() != NULL) { 1579 m = find_method(default_methods(), name, signature); 1580 } 1581 // Look up interfaces 1582 if (m == NULL) { 1583 m = lookup_method_in_all_interfaces(name, signature, find_defaults); 1584 } 1585 return m; 1586 } 1587 1588 // lookup a method in all the interfaces that this class implements 1589 // Do NOT return private or static methods, new in JDK8 which are not externally visible 1590 // They should only be found in the initial InterfaceMethodRef 1591 Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name, 1592 Symbol* signature, 1593 DefaultsLookupMode defaults_mode) const { 1594 Array<Klass*>* all_ifs = transitive_interfaces(); 1595 int num_ifs = all_ifs->length(); 1596 InstanceKlass *ik = NULL; 1597 for (int i = 0; i < num_ifs; i++) { 1598 ik = InstanceKlass::cast(all_ifs->at(i)); 1599 Method* m = ik->lookup_method(name, signature); 1600 if (m != NULL && m->is_public() && !m->is_static() && 1601 ((defaults_mode != skip_defaults) || !m->is_default_method())) { 1602 return m; 1603 } 1604 } 1605 return NULL; 1606 } 1607 1608 /* jni_id_for_impl for jfieldIds only */ 1609 JNIid* InstanceKlass::jni_id_for_impl(int offset) { 1610 MutexLocker ml(JfieldIdCreation_lock); 1611 // Retry lookup after we got the lock 1612 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset); 1613 if (probe == NULL) { 1614 // Slow case, allocate new static field identifier 1615 probe = new JNIid(this, offset, jni_ids()); 1616 set_jni_ids(probe); 1617 } 1618 return probe; 1619 } 1620 1621 1622 /* jni_id_for for jfieldIds only */ 1623 JNIid* InstanceKlass::jni_id_for(int offset) { 1624 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset); 1625 if (probe == NULL) { 1626 probe = jni_id_for_impl(offset); 1627 } 1628 return probe; 1629 } 1630 1631 u2 InstanceKlass::enclosing_method_data(int offset) const { 1632 const Array<jushort>* const inner_class_list = inner_classes(); 1633 if (inner_class_list == NULL) { 1634 return 0; 1635 } 1636 const int length = inner_class_list->length(); 1637 if (length % inner_class_next_offset == 0) { 1638 return 0; 1639 } 1640 const int index = length - enclosing_method_attribute_size; 1641 assert(offset < enclosing_method_attribute_size, "invalid offset"); 1642 return inner_class_list->at(index + offset); 1643 } 1644 1645 void InstanceKlass::set_enclosing_method_indices(u2 class_index, 1646 u2 method_index) { 1647 Array<jushort>* inner_class_list = inner_classes(); 1648 assert (inner_class_list != NULL, "_inner_classes list is not set up"); 1649 int length = inner_class_list->length(); 1650 if (length % inner_class_next_offset == enclosing_method_attribute_size) { 1651 int index = length - enclosing_method_attribute_size; 1652 inner_class_list->at_put( 1653 index + enclosing_method_class_index_offset, class_index); 1654 inner_class_list->at_put( 1655 index + enclosing_method_method_index_offset, method_index); 1656 } 1657 } 1658 1659 // Lookup or create a jmethodID. 1660 // This code is called by the VMThread and JavaThreads so the 1661 // locking has to be done very carefully to avoid deadlocks 1662 // and/or other cache consistency problems. 1663 // 1664 jmethodID InstanceKlass::get_jmethod_id(const methodHandle& method_h) { 1665 size_t idnum = (size_t)method_h->method_idnum(); 1666 jmethodID* jmeths = methods_jmethod_ids_acquire(); 1667 size_t length = 0; 1668 jmethodID id = NULL; 1669 1670 // We use a double-check locking idiom here because this cache is 1671 // performance sensitive. In the normal system, this cache only 1672 // transitions from NULL to non-NULL which is safe because we use 1673 // release_set_methods_jmethod_ids() to advertise the new cache. 1674 // A partially constructed cache should never be seen by a racing 1675 // thread. We also use release_store_ptr() to save a new jmethodID 1676 // in the cache so a partially constructed jmethodID should never be 1677 // seen either. Cache reads of existing jmethodIDs proceed without a 1678 // lock, but cache writes of a new jmethodID requires uniqueness and 1679 // creation of the cache itself requires no leaks so a lock is 1680 // generally acquired in those two cases. 1681 // 1682 // If the RedefineClasses() API has been used, then this cache can 1683 // grow and we'll have transitions from non-NULL to bigger non-NULL. 1684 // Cache creation requires no leaks and we require safety between all 1685 // cache accesses and freeing of the old cache so a lock is generally 1686 // acquired when the RedefineClasses() API has been used. 1687 1688 if (jmeths != NULL) { 1689 // the cache already exists 1690 if (!idnum_can_increment()) { 1691 // the cache can't grow so we can just get the current values 1692 get_jmethod_id_length_value(jmeths, idnum, &length, &id); 1693 } else { 1694 // cache can grow so we have to be more careful 1695 if (Threads::number_of_threads() == 0 || 1696 SafepointSynchronize::is_at_safepoint()) { 1697 // we're single threaded or at a safepoint - no locking needed 1698 get_jmethod_id_length_value(jmeths, idnum, &length, &id); 1699 } else { 1700 MutexLocker ml(JmethodIdCreation_lock); 1701 get_jmethod_id_length_value(jmeths, idnum, &length, &id); 1702 } 1703 } 1704 } 1705 // implied else: 1706 // we need to allocate a cache so default length and id values are good 1707 1708 if (jmeths == NULL || // no cache yet 1709 length <= idnum || // cache is too short 1710 id == NULL) { // cache doesn't contain entry 1711 1712 // This function can be called by the VMThread so we have to do all 1713 // things that might block on a safepoint before grabbing the lock. 1714 // Otherwise, we can deadlock with the VMThread or have a cache 1715 // consistency issue. These vars keep track of what we might have 1716 // to free after the lock is dropped. 1717 jmethodID to_dealloc_id = NULL; 1718 jmethodID* to_dealloc_jmeths = NULL; 1719 1720 // may not allocate new_jmeths or use it if we allocate it 1721 jmethodID* new_jmeths = NULL; 1722 if (length <= idnum) { 1723 // allocate a new cache that might be used 1724 size_t size = MAX2(idnum+1, (size_t)idnum_allocated_count()); 1725 new_jmeths = NEW_C_HEAP_ARRAY(jmethodID, size+1, mtClass); 1726 memset(new_jmeths, 0, (size+1)*sizeof(jmethodID)); 1727 // cache size is stored in element[0], other elements offset by one 1728 new_jmeths[0] = (jmethodID)size; 1729 } 1730 1731 // allocate a new jmethodID that might be used 1732 jmethodID new_id = NULL; 1733 if (method_h->is_old() && !method_h->is_obsolete()) { 1734 // The method passed in is old (but not obsolete), we need to use the current version 1735 Method* current_method = method_with_idnum((int)idnum); 1736 assert(current_method != NULL, "old and but not obsolete, so should exist"); 1737 new_id = Method::make_jmethod_id(class_loader_data(), current_method); 1738 } else { 1739 // It is the current version of the method or an obsolete method, 1740 // use the version passed in 1741 new_id = Method::make_jmethod_id(class_loader_data(), method_h()); 1742 } 1743 1744 if (Threads::number_of_threads() == 0 || 1745 SafepointSynchronize::is_at_safepoint()) { 1746 // we're single threaded or at a safepoint - no locking needed 1747 id = get_jmethod_id_fetch_or_update(idnum, new_id, new_jmeths, 1748 &to_dealloc_id, &to_dealloc_jmeths); 1749 } else { 1750 MutexLocker ml(JmethodIdCreation_lock); 1751 id = get_jmethod_id_fetch_or_update(idnum, new_id, new_jmeths, 1752 &to_dealloc_id, &to_dealloc_jmeths); 1753 } 1754 1755 // The lock has been dropped so we can free resources. 1756 // Free up either the old cache or the new cache if we allocated one. 1757 if (to_dealloc_jmeths != NULL) { 1758 FreeHeap(to_dealloc_jmeths); 1759 } 1760 // free up the new ID since it wasn't needed 1761 if (to_dealloc_id != NULL) { 1762 Method::destroy_jmethod_id(class_loader_data(), to_dealloc_id); 1763 } 1764 } 1765 return id; 1766 } 1767 1768 // Figure out how many jmethodIDs haven't been allocated, and make 1769 // sure space for them is pre-allocated. This makes getting all 1770 // method ids much, much faster with classes with more than 8 1771 // methods, and has a *substantial* effect on performance with jvmti 1772 // code that loads all jmethodIDs for all classes. 1773 void InstanceKlass::ensure_space_for_methodids(int start_offset) { 1774 int new_jmeths = 0; 1775 int length = methods()->length(); 1776 for (int index = start_offset; index < length; index++) { 1777 Method* m = methods()->at(index); 1778 jmethodID id = m->find_jmethod_id_or_null(); 1779 if (id == NULL) { 1780 new_jmeths++; 1781 } 1782 } 1783 if (new_jmeths != 0) { 1784 Method::ensure_jmethod_ids(class_loader_data(), new_jmeths); 1785 } 1786 } 1787 1788 // Common code to fetch the jmethodID from the cache or update the 1789 // cache with the new jmethodID. This function should never do anything 1790 // that causes the caller to go to a safepoint or we can deadlock with 1791 // the VMThread or have cache consistency issues. 1792 // 1793 jmethodID InstanceKlass::get_jmethod_id_fetch_or_update( 1794 size_t idnum, jmethodID new_id, 1795 jmethodID* new_jmeths, jmethodID* to_dealloc_id_p, 1796 jmethodID** to_dealloc_jmeths_p) { 1797 assert(new_id != NULL, "sanity check"); 1798 assert(to_dealloc_id_p != NULL, "sanity check"); 1799 assert(to_dealloc_jmeths_p != NULL, "sanity check"); 1800 assert(Threads::number_of_threads() == 0 || 1801 SafepointSynchronize::is_at_safepoint() || 1802 JmethodIdCreation_lock->owned_by_self(), "sanity check"); 1803 1804 // reacquire the cache - we are locked, single threaded or at a safepoint 1805 jmethodID* jmeths = methods_jmethod_ids_acquire(); 1806 jmethodID id = NULL; 1807 size_t length = 0; 1808 1809 if (jmeths == NULL || // no cache yet 1810 (length = (size_t)jmeths[0]) <= idnum) { // cache is too short 1811 if (jmeths != NULL) { 1812 // copy any existing entries from the old cache 1813 for (size_t index = 0; index < length; index++) { 1814 new_jmeths[index+1] = jmeths[index+1]; 1815 } 1816 *to_dealloc_jmeths_p = jmeths; // save old cache for later delete 1817 } 1818 release_set_methods_jmethod_ids(jmeths = new_jmeths); 1819 } else { 1820 // fetch jmethodID (if any) from the existing cache 1821 id = jmeths[idnum+1]; 1822 *to_dealloc_jmeths_p = new_jmeths; // save new cache for later delete 1823 } 1824 if (id == NULL) { 1825 // No matching jmethodID in the existing cache or we have a new 1826 // cache or we just grew the cache. This cache write is done here 1827 // by the first thread to win the foot race because a jmethodID 1828 // needs to be unique once it is generally available. 1829 id = new_id; 1830 1831 // The jmethodID cache can be read while unlocked so we have to 1832 // make sure the new jmethodID is complete before installing it 1833 // in the cache. 1834 OrderAccess::release_store_ptr(&jmeths[idnum+1], id); 1835 } else { 1836 *to_dealloc_id_p = new_id; // save new id for later delete 1837 } 1838 return id; 1839 } 1840 1841 1842 // Common code to get the jmethodID cache length and the jmethodID 1843 // value at index idnum if there is one. 1844 // 1845 void InstanceKlass::get_jmethod_id_length_value(jmethodID* cache, 1846 size_t idnum, size_t *length_p, jmethodID* id_p) { 1847 assert(cache != NULL, "sanity check"); 1848 assert(length_p != NULL, "sanity check"); 1849 assert(id_p != NULL, "sanity check"); 1850 1851 // cache size is stored in element[0], other elements offset by one 1852 *length_p = (size_t)cache[0]; 1853 if (*length_p <= idnum) { // cache is too short 1854 *id_p = NULL; 1855 } else { 1856 *id_p = cache[idnum+1]; // fetch jmethodID (if any) 1857 } 1858 } 1859 1860 1861 // Lookup a jmethodID, NULL if not found. Do no blocking, no allocations, no handles 1862 jmethodID InstanceKlass::jmethod_id_or_null(Method* method) { 1863 size_t idnum = (size_t)method->method_idnum(); 1864 jmethodID* jmeths = methods_jmethod_ids_acquire(); 1865 size_t length; // length assigned as debugging crumb 1866 jmethodID id = NULL; 1867 if (jmeths != NULL && // If there is a cache 1868 (length = (size_t)jmeths[0]) > idnum) { // and if it is long enough, 1869 id = jmeths[idnum+1]; // Look up the id (may be NULL) 1870 } 1871 return id; 1872 } 1873 1874 inline DependencyContext InstanceKlass::dependencies() { 1875 DependencyContext dep_context(&_dep_context); 1876 return dep_context; 1877 } 1878 1879 int InstanceKlass::mark_dependent_nmethods(KlassDepChange& changes) { 1880 return dependencies().mark_dependent_nmethods(changes); 1881 } 1882 1883 void InstanceKlass::add_dependent_nmethod(nmethod* nm) { 1884 dependencies().add_dependent_nmethod(nm); 1885 } 1886 1887 void InstanceKlass::remove_dependent_nmethod(nmethod* nm, bool delete_immediately) { 1888 dependencies().remove_dependent_nmethod(nm, delete_immediately); 1889 } 1890 1891 #ifndef PRODUCT 1892 void InstanceKlass::print_dependent_nmethods(bool verbose) { 1893 dependencies().print_dependent_nmethods(verbose); 1894 } 1895 1896 bool InstanceKlass::is_dependent_nmethod(nmethod* nm) { 1897 return dependencies().is_dependent_nmethod(nm); 1898 } 1899 #endif //PRODUCT 1900 1901 void InstanceKlass::clean_weak_instanceklass_links(BoolObjectClosure* is_alive) { 1902 clean_implementors_list(is_alive); 1903 clean_method_data(is_alive); 1904 1905 // Since GC iterates InstanceKlasses sequentially, it is safe to remove stale entries here. 1906 DependencyContext dep_context(&_dep_context); 1907 dep_context.expunge_stale_entries(); 1908 } 1909 1910 void InstanceKlass::clean_implementors_list(BoolObjectClosure* is_alive) { 1911 assert(class_loader_data()->is_alive(is_alive), "this klass should be live"); 1912 if (is_interface()) { 1913 if (ClassUnloading) { 1914 Klass* impl = implementor(); 1915 if (impl != NULL) { 1916 if (!impl->is_loader_alive(is_alive)) { 1917 // remove this guy 1918 Klass** klass = adr_implementor(); 1919 assert(klass != NULL, "null klass"); 1920 if (klass != NULL) { 1921 *klass = NULL; 1922 } 1923 } 1924 } 1925 } 1926 } 1927 } 1928 1929 void InstanceKlass::clean_method_data(BoolObjectClosure* is_alive) { 1930 for (int m = 0; m < methods()->length(); m++) { 1931 MethodData* mdo = methods()->at(m)->method_data(); 1932 if (mdo != NULL) { 1933 mdo->clean_method_data(is_alive); 1934 } 1935 } 1936 } 1937 1938 bool InstanceKlass::supers_have_passed_fingerprint_checks() { 1939 if (java_super() != NULL && !java_super()->has_passed_fingerprint_check()) { 1940 ResourceMark rm; 1941 log_trace(class, fingerprint)("%s : super %s not fingerprinted", external_name(), java_super()->external_name()); 1942 return false; 1943 } 1944 1945 Array<Klass*>* local_interfaces = this->local_interfaces(); 1946 if (local_interfaces != NULL) { 1947 int length = local_interfaces->length(); 1948 for (int i = 0; i < length; i++) { 1949 InstanceKlass* intf = InstanceKlass::cast(local_interfaces->at(i)); 1950 if (!intf->has_passed_fingerprint_check()) { 1951 ResourceMark rm; 1952 log_trace(class, fingerprint)("%s : interface %s not fingerprinted", external_name(), intf->external_name()); 1953 return false; 1954 } 1955 } 1956 } 1957 1958 return true; 1959 } 1960 1961 bool InstanceKlass::should_store_fingerprint() { 1962 #if INCLUDE_AOT 1963 // We store the fingerprint into the InstanceKlass only in the following 2 cases: 1964 if (CalculateClassFingerprint) { 1965 // (1) We are running AOT to generate a shared library. 1966 return true; 1967 } 1968 if (DumpSharedSpaces) { 1969 // (2) We are running -Xshare:dump to create a shared archive 1970 return true; 1971 } 1972 #endif 1973 1974 // In all other cases we might set the _misc_has_passed_fingerprint_check bit, 1975 // but do not store the 64-bit fingerprint to save space. 1976 return false; 1977 } 1978 1979 bool InstanceKlass::has_stored_fingerprint() const { 1980 #if INCLUDE_AOT 1981 return should_store_fingerprint() || is_shared(); 1982 #else 1983 return false; 1984 #endif 1985 } 1986 1987 uint64_t InstanceKlass::get_stored_fingerprint() const { 1988 address adr = adr_fingerprint(); 1989 if (adr != NULL) { 1990 return (uint64_t)Bytes::get_native_u8(adr); // adr may not be 64-bit aligned 1991 } 1992 return 0; 1993 } 1994 1995 void InstanceKlass::store_fingerprint(uint64_t fingerprint) { 1996 address adr = adr_fingerprint(); 1997 if (adr != NULL) { 1998 Bytes::put_native_u8(adr, (u8)fingerprint); // adr may not be 64-bit aligned 1999 2000 ResourceMark rm; 2001 log_trace(class, fingerprint)("stored as " PTR64_FORMAT " for class %s", fingerprint, external_name()); 2002 } 2003 } 2004 2005 void InstanceKlass::metaspace_pointers_do(MetaspaceClosure* it) { 2006 Klass::metaspace_pointers_do(it); 2007 2008 if (log_is_enabled(Trace, cds)) { 2009 ResourceMark rm; 2010 log_trace(cds)("Iter(InstanceKlass): %p (%s)", this, external_name()); 2011 } 2012 2013 it->push(&_annotations); 2014 it->push((Klass**)&_array_klasses); 2015 it->push(&_constants); 2016 it->push(&_inner_classes); 2017 it->push(&_array_name); 2018 #if INCLUDE_JVMTI 2019 it->push(&_previous_versions); 2020 #endif 2021 it->push(&_methods); 2022 it->push(&_default_methods); 2023 it->push(&_local_interfaces); 2024 it->push(&_transitive_interfaces); 2025 it->push(&_method_ordering); 2026 it->push(&_default_vtable_indices); 2027 it->push(&_fields); 2028 2029 if (itable_length() > 0) { 2030 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable(); 2031 int method_table_offset_in_words = ioe->offset()/wordSize; 2032 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words()) 2033 / itableOffsetEntry::size(); 2034 2035 for (int i = 0; i < nof_interfaces; i ++, ioe ++) { 2036 if (ioe->interface_klass() != NULL) { 2037 it->push(ioe->interface_klass_addr()); 2038 itableMethodEntry* ime = ioe->first_method_entry(this); 2039 int n = klassItable::method_count_for_interface(ioe->interface_klass()); 2040 for (int index = 0; index < n; index ++) { 2041 it->push(ime[index].method_addr()); 2042 } 2043 } 2044 } 2045 } 2046 } 2047 2048 void InstanceKlass::remove_unshareable_info() { 2049 Klass::remove_unshareable_info(); 2050 2051 if (is_in_error_state()) { 2052 // Classes are attempted to link during dumping and may fail, 2053 // but these classes are still in the dictionary and class list in CLD. 2054 // Check in_error state first because in_error is > linked state, so 2055 // is_linked() is true. 2056 // If there's a linking error, there is nothing else to remove. 2057 return; 2058 } 2059 2060 // Unlink the class 2061 if (is_linked()) { 2062 unlink_class(); 2063 } 2064 init_implementor(); 2065 2066 constants()->remove_unshareable_info(); 2067 2068 for (int i = 0; i < methods()->length(); i++) { 2069 Method* m = methods()->at(i); 2070 m->remove_unshareable_info(); 2071 } 2072 2073 // do array classes also. 2074 if (array_klasses() != NULL) { 2075 array_klasses()->remove_unshareable_info(); 2076 } 2077 2078 // These are not allocated from metaspace, but they should should all be empty 2079 // during dump time, so we don't need to worry about them in InstanceKlass::iterate(). 2080 guarantee(_source_debug_extension == NULL, "must be"); 2081 guarantee(_dep_context == DependencyContext::EMPTY, "must be"); 2082 guarantee(_osr_nmethods_head == NULL, "must be"); 2083 2084 #if INCLUDE_JVMTI 2085 guarantee(_breakpoints == NULL, "must be"); 2086 guarantee(_previous_versions == NULL, "must be"); 2087 #endif 2088 2089 _init_thread = NULL; 2090 _methods_jmethod_ids = NULL; 2091 _jni_ids = NULL; 2092 _oop_map_cache = NULL; 2093 } 2094 2095 void InstanceKlass::remove_java_mirror() { 2096 Klass::remove_java_mirror(); 2097 2098 // do array classes also. 2099 if (array_klasses() != NULL) { 2100 array_klasses()->remove_java_mirror(); 2101 } 2102 } 2103 2104 void InstanceKlass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain, TRAPS) { 2105 set_package(loader_data, CHECK); 2106 Klass::restore_unshareable_info(loader_data, protection_domain, CHECK); 2107 2108 Array<Method*>* methods = this->methods(); 2109 int num_methods = methods->length(); 2110 for (int index2 = 0; index2 < num_methods; ++index2) { 2111 methodHandle m(THREAD, methods->at(index2)); 2112 m->restore_unshareable_info(CHECK); 2113 } 2114 if (JvmtiExport::has_redefined_a_class()) { 2115 // Reinitialize vtable because RedefineClasses may have changed some 2116 // entries in this vtable for super classes so the CDS vtable might 2117 // point to old or obsolete entries. RedefineClasses doesn't fix up 2118 // vtables in the shared system dictionary, only the main one. 2119 // It also redefines the itable too so fix that too. 2120 ResourceMark rm(THREAD); 2121 vtable().initialize_vtable(false, CHECK); 2122 itable().initialize_itable(false, CHECK); 2123 } 2124 2125 // restore constant pool resolved references 2126 constants()->restore_unshareable_info(CHECK); 2127 2128 if (array_klasses() != NULL) { 2129 // Array classes have null protection domain. 2130 // --> see ArrayKlass::complete_create_array_klass() 2131 array_klasses()->restore_unshareable_info(ClassLoaderData::the_null_class_loader_data(), Handle(), CHECK); 2132 } 2133 } 2134 2135 // returns true IFF is_in_error_state() has been changed as a result of this call. 2136 bool InstanceKlass::check_sharing_error_state() { 2137 assert(DumpSharedSpaces, "should only be called during dumping"); 2138 bool old_state = is_in_error_state(); 2139 2140 if (!is_in_error_state()) { 2141 bool bad = false; 2142 for (InstanceKlass* sup = java_super(); sup; sup = sup->java_super()) { 2143 if (sup->is_in_error_state()) { 2144 bad = true; 2145 break; 2146 } 2147 } 2148 if (!bad) { 2149 Array<Klass*>* interfaces = transitive_interfaces(); 2150 for (int i = 0; i < interfaces->length(); i++) { 2151 Klass* iface = interfaces->at(i); 2152 if (InstanceKlass::cast(iface)->is_in_error_state()) { 2153 bad = true; 2154 break; 2155 } 2156 } 2157 } 2158 2159 if (bad) { 2160 set_in_error_state(); 2161 } 2162 } 2163 2164 return (old_state != is_in_error_state()); 2165 } 2166 2167 #if INCLUDE_JVMTI 2168 static void clear_all_breakpoints(Method* m) { 2169 m->clear_all_breakpoints(); 2170 } 2171 #endif 2172 2173 void InstanceKlass::notify_unload_class(InstanceKlass* ik) { 2174 // notify the debugger 2175 if (JvmtiExport::should_post_class_unload()) { 2176 JvmtiExport::post_class_unload(ik); 2177 } 2178 2179 // notify ClassLoadingService of class unload 2180 ClassLoadingService::notify_class_unloaded(ik); 2181 } 2182 2183 void InstanceKlass::release_C_heap_structures(InstanceKlass* ik) { 2184 // Clean up C heap 2185 ik->release_C_heap_structures(); 2186 ik->constants()->release_C_heap_structures(); 2187 } 2188 2189 void InstanceKlass::release_C_heap_structures() { 2190 // Can't release the constant pool here because the constant pool can be 2191 // deallocated separately from the InstanceKlass for default methods and 2192 // redefine classes. 2193 2194 // Deallocate oop map cache 2195 if (_oop_map_cache != NULL) { 2196 delete _oop_map_cache; 2197 _oop_map_cache = NULL; 2198 } 2199 2200 // Deallocate JNI identifiers for jfieldIDs 2201 JNIid::deallocate(jni_ids()); 2202 set_jni_ids(NULL); 2203 2204 jmethodID* jmeths = methods_jmethod_ids_acquire(); 2205 if (jmeths != (jmethodID*)NULL) { 2206 release_set_methods_jmethod_ids(NULL); 2207 FreeHeap(jmeths); 2208 } 2209 2210 // Release dependencies. 2211 // It is desirable to use DC::remove_all_dependents() here, but, unfortunately, 2212 // it is not safe (see JDK-8143408). The problem is that the klass dependency 2213 // context can contain live dependencies, since there's a race between nmethod & 2214 // klass unloading. If the klass is dead when nmethod unloading happens, relevant 2215 // dependencies aren't removed from the context associated with the class (see 2216 // nmethod::flush_dependencies). It ends up during klass unloading as seemingly 2217 // live dependencies pointing to unloaded nmethods and causes a crash in 2218 // DC::remove_all_dependents() when it touches unloaded nmethod. 2219 dependencies().wipe(); 2220 2221 #if INCLUDE_JVMTI 2222 // Deallocate breakpoint records 2223 if (breakpoints() != 0x0) { 2224 methods_do(clear_all_breakpoints); 2225 assert(breakpoints() == 0x0, "should have cleared breakpoints"); 2226 } 2227 2228 // deallocate the cached class file 2229 if (_cached_class_file != NULL && !MetaspaceShared::is_in_shared_space(_cached_class_file)) { 2230 os::free(_cached_class_file); 2231 _cached_class_file = NULL; 2232 } 2233 #endif 2234 2235 // Decrement symbol reference counts associated with the unloaded class. 2236 if (_name != NULL) _name->decrement_refcount(); 2237 // unreference array name derived from this class name (arrays of an unloaded 2238 // class can't be referenced anymore). 2239 if (_array_name != NULL) _array_name->decrement_refcount(); 2240 if (_source_debug_extension != NULL) FREE_C_HEAP_ARRAY(char, _source_debug_extension); 2241 2242 assert(_total_instanceKlass_count >= 1, "Sanity check"); 2243 Atomic::dec(&_total_instanceKlass_count); 2244 } 2245 2246 void InstanceKlass::set_source_debug_extension(const char* array, int length) { 2247 if (array == NULL) { 2248 _source_debug_extension = NULL; 2249 } else { 2250 // Adding one to the attribute length in order to store a null terminator 2251 // character could cause an overflow because the attribute length is 2252 // already coded with an u4 in the classfile, but in practice, it's 2253 // unlikely to happen. 2254 assert((length+1) > length, "Overflow checking"); 2255 char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass); 2256 for (int i = 0; i < length; i++) { 2257 sde[i] = array[i]; 2258 } 2259 sde[length] = '\0'; 2260 _source_debug_extension = sde; 2261 } 2262 } 2263 2264 address InstanceKlass::static_field_addr(int offset) { 2265 return (address)(offset + InstanceMirrorKlass::offset_of_static_fields() + cast_from_oop<intptr_t>(java_mirror())); 2266 } 2267 2268 2269 const char* InstanceKlass::signature_name() const { 2270 int hash_len = 0; 2271 char hash_buf[40]; 2272 2273 // If this is an anonymous class, append a hash to make the name unique 2274 if (is_anonymous()) { 2275 intptr_t hash = (java_mirror() != NULL) ? java_mirror()->identity_hash() : 0; 2276 jio_snprintf(hash_buf, sizeof(hash_buf), "/" UINTX_FORMAT, (uintx)hash); 2277 hash_len = (int)strlen(hash_buf); 2278 } 2279 2280 // Get the internal name as a c string 2281 const char* src = (const char*) (name()->as_C_string()); 2282 const int src_length = (int)strlen(src); 2283 2284 char* dest = NEW_RESOURCE_ARRAY(char, src_length + hash_len + 3); 2285 2286 // Add L as type indicator 2287 int dest_index = 0; 2288 dest[dest_index++] = 'L'; 2289 2290 // Add the actual class name 2291 for (int src_index = 0; src_index < src_length; ) { 2292 dest[dest_index++] = src[src_index++]; 2293 } 2294 2295 // If we have a hash, append it 2296 for (int hash_index = 0; hash_index < hash_len; ) { 2297 dest[dest_index++] = hash_buf[hash_index++]; 2298 } 2299 2300 // Add the semicolon and the NULL 2301 dest[dest_index++] = ';'; 2302 dest[dest_index] = '\0'; 2303 return dest; 2304 } 2305 2306 // Used to obtain the package name from a fully qualified class name. 2307 Symbol* InstanceKlass::package_from_name(const Symbol* name, TRAPS) { 2308 if (name == NULL) { 2309 return NULL; 2310 } else { 2311 if (name->utf8_length() <= 0) { 2312 return NULL; 2313 } 2314 ResourceMark rm; 2315 const char* package_name = ClassLoader::package_from_name((const char*) name->as_C_string()); 2316 if (package_name == NULL) { 2317 return NULL; 2318 } 2319 Symbol* pkg_name = SymbolTable::new_symbol(package_name, THREAD); 2320 return pkg_name; 2321 } 2322 } 2323 2324 ModuleEntry* InstanceKlass::module() const { 2325 if (!in_unnamed_package()) { 2326 return _package_entry->module(); 2327 } 2328 const Klass* host = host_klass(); 2329 if (host == NULL) { 2330 return class_loader_data()->unnamed_module(); 2331 } 2332 return host->class_loader_data()->unnamed_module(); 2333 } 2334 2335 void InstanceKlass::set_package(ClassLoaderData* loader_data, TRAPS) { 2336 2337 // ensure java/ packages only loaded by boot or platform builtin loaders 2338 Handle class_loader(THREAD, loader_data->class_loader()); 2339 check_prohibited_package(name(), class_loader, CHECK); 2340 2341 TempNewSymbol pkg_name = package_from_name(name(), CHECK); 2342 2343 if (pkg_name != NULL && loader_data != NULL) { 2344 2345 // Find in class loader's package entry table. 2346 _package_entry = loader_data->packages()->lookup_only(pkg_name); 2347 2348 // If the package name is not found in the loader's package 2349 // entry table, it is an indication that the package has not 2350 // been defined. Consider it defined within the unnamed module. 2351 if (_package_entry == NULL) { 2352 ResourceMark rm; 2353 2354 if (!ModuleEntryTable::javabase_defined()) { 2355 // Before java.base is defined during bootstrapping, define all packages in 2356 // the java.base module. If a non-java.base package is erroneously placed 2357 // in the java.base module it will be caught later when java.base 2358 // is defined by ModuleEntryTable::verify_javabase_packages check. 2359 assert(ModuleEntryTable::javabase_moduleEntry() != NULL, JAVA_BASE_NAME " module is NULL"); 2360 _package_entry = loader_data->packages()->lookup(pkg_name, ModuleEntryTable::javabase_moduleEntry()); 2361 } else { 2362 assert(loader_data->unnamed_module() != NULL, "unnamed module is NULL"); 2363 _package_entry = loader_data->packages()->lookup(pkg_name, 2364 loader_data->unnamed_module()); 2365 } 2366 2367 // A package should have been successfully created 2368 assert(_package_entry != NULL, "Package entry for class %s not found, loader %s", 2369 name()->as_C_string(), loader_data->loader_name()); 2370 } 2371 2372 if (log_is_enabled(Debug, module)) { 2373 ResourceMark rm; 2374 ModuleEntry* m = _package_entry->module(); 2375 log_trace(module)("Setting package: class: %s, package: %s, loader: %s, module: %s", 2376 external_name(), 2377 pkg_name->as_C_string(), 2378 loader_data->loader_name(), 2379 (m->is_named() ? m->name()->as_C_string() : UNNAMED_MODULE)); 2380 } 2381 } else { 2382 ResourceMark rm; 2383 log_trace(module)("Setting package: class: %s, package: unnamed, loader: %s, module: %s", 2384 external_name(), 2385 (loader_data != NULL) ? loader_data->loader_name() : "NULL", 2386 UNNAMED_MODULE); 2387 } 2388 } 2389 2390 2391 // different versions of is_same_class_package 2392 2393 bool InstanceKlass::is_same_class_package(const Klass* class2) const { 2394 oop classloader1 = this->class_loader(); 2395 PackageEntry* classpkg1 = this->package(); 2396 if (class2->is_objArray_klass()) { 2397 class2 = ObjArrayKlass::cast(class2)->bottom_klass(); 2398 } 2399 2400 oop classloader2; 2401 PackageEntry* classpkg2; 2402 if (class2->is_instance_klass()) { 2403 classloader2 = class2->class_loader(); 2404 classpkg2 = class2->package(); 2405 } else { 2406 assert(class2->is_typeArray_klass(), "should be type array"); 2407 classloader2 = NULL; 2408 classpkg2 = NULL; 2409 } 2410 2411 // Same package is determined by comparing class loader 2412 // and package entries. Both must be the same. This rule 2413 // applies even to classes that are defined in the unnamed 2414 // package, they still must have the same class loader. 2415 if ((classloader1 == classloader2) && (classpkg1 == classpkg2)) { 2416 return true; 2417 } 2418 2419 return false; 2420 } 2421 2422 // return true if this class and other_class are in the same package. Classloader 2423 // and classname information is enough to determine a class's package 2424 bool InstanceKlass::is_same_class_package(oop other_class_loader, 2425 const Symbol* other_class_name) const { 2426 if (class_loader() != other_class_loader) { 2427 return false; 2428 } 2429 if (name()->fast_compare(other_class_name) == 0) { 2430 return true; 2431 } 2432 2433 { 2434 ResourceMark rm; 2435 2436 bool bad_class_name = false; 2437 const char* other_pkg = 2438 ClassLoader::package_from_name((const char*) other_class_name->as_C_string(), &bad_class_name); 2439 if (bad_class_name) { 2440 return false; 2441 } 2442 // Check that package_from_name() returns NULL, not "", if there is no package. 2443 assert(other_pkg == NULL || strlen(other_pkg) > 0, "package name is empty string"); 2444 2445 const Symbol* const this_package_name = 2446 this->package() != NULL ? this->package()->name() : NULL; 2447 2448 if (this_package_name == NULL || other_pkg == NULL) { 2449 // One of the two doesn't have a package. Only return true if the other 2450 // one also doesn't have a package. 2451 return (const char*)this_package_name == other_pkg; 2452 } 2453 2454 // Check if package is identical 2455 return this_package_name->equals(other_pkg); 2456 } 2457 } 2458 2459 // Returns true iff super_method can be overridden by a method in targetclassname 2460 // See JLS 3rd edition 8.4.6.1 2461 // Assumes name-signature match 2462 // "this" is InstanceKlass of super_method which must exist 2463 // note that the InstanceKlass of the method in the targetclassname has not always been created yet 2464 bool InstanceKlass::is_override(const methodHandle& super_method, Handle targetclassloader, Symbol* targetclassname, TRAPS) { 2465 // Private methods can not be overridden 2466 if (super_method->is_private()) { 2467 return false; 2468 } 2469 // If super method is accessible, then override 2470 if ((super_method->is_protected()) || 2471 (super_method->is_public())) { 2472 return true; 2473 } 2474 // Package-private methods are not inherited outside of package 2475 assert(super_method->is_package_private(), "must be package private"); 2476 return(is_same_class_package(targetclassloader(), targetclassname)); 2477 } 2478 2479 // Only boot and platform class loaders can define classes in "java/" packages. 2480 void InstanceKlass::check_prohibited_package(Symbol* class_name, 2481 Handle class_loader, 2482 TRAPS) { 2483 if (!class_loader.is_null() && 2484 !SystemDictionary::is_platform_class_loader(class_loader()) && 2485 class_name != NULL) { 2486 ResourceMark rm(THREAD); 2487 char* name = class_name->as_C_string(); 2488 if (strncmp(name, JAVAPKG, JAVAPKG_LEN) == 0 && name[JAVAPKG_LEN] == '/') { 2489 TempNewSymbol pkg_name = InstanceKlass::package_from_name(class_name, CHECK); 2490 assert(pkg_name != NULL, "Error in parsing package name starting with 'java/'"); 2491 name = pkg_name->as_C_string(); 2492 const char* class_loader_name = SystemDictionary::loader_name(class_loader()); 2493 StringUtils::replace_no_expand(name, "/", "."); 2494 const char* msg_text1 = "Class loader (instance of): "; 2495 const char* msg_text2 = " tried to load prohibited package name: "; 2496 size_t len = strlen(msg_text1) + strlen(class_loader_name) + strlen(msg_text2) + strlen(name) + 1; 2497 char* message = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, len); 2498 jio_snprintf(message, len, "%s%s%s%s", msg_text1, class_loader_name, msg_text2, name); 2499 THROW_MSG(vmSymbols::java_lang_SecurityException(), message); 2500 } 2501 } 2502 return; 2503 } 2504 2505 // tell if two classes have the same enclosing class (at package level) 2506 bool InstanceKlass::is_same_package_member(const Klass* class2, TRAPS) const { 2507 if (class2 == this) return true; 2508 if (!class2->is_instance_klass()) return false; 2509 2510 // must be in same package before we try anything else 2511 if (!is_same_class_package(class2)) 2512 return false; 2513 2514 // As long as there is an outer_this.getEnclosingClass, 2515 // shift the search outward. 2516 const InstanceKlass* outer_this = this; 2517 for (;;) { 2518 // As we walk along, look for equalities between outer_this and class2. 2519 // Eventually, the walks will terminate as outer_this stops 2520 // at the top-level class around the original class. 2521 bool ignore_inner_is_member; 2522 const Klass* next = outer_this->compute_enclosing_class(&ignore_inner_is_member, 2523 CHECK_false); 2524 if (next == NULL) break; 2525 if (next == class2) return true; 2526 outer_this = InstanceKlass::cast(next); 2527 } 2528 2529 // Now do the same for class2. 2530 const InstanceKlass* outer2 = InstanceKlass::cast(class2); 2531 for (;;) { 2532 bool ignore_inner_is_member; 2533 Klass* next = outer2->compute_enclosing_class(&ignore_inner_is_member, 2534 CHECK_false); 2535 if (next == NULL) break; 2536 // Might as well check the new outer against all available values. 2537 if (next == this) return true; 2538 if (next == outer_this) return true; 2539 outer2 = InstanceKlass::cast(next); 2540 } 2541 2542 // If by this point we have not found an equality between the 2543 // two classes, we know they are in separate package members. 2544 return false; 2545 } 2546 2547 bool InstanceKlass::find_inner_classes_attr(int* ooff, int* noff, TRAPS) const { 2548 constantPoolHandle i_cp(THREAD, constants()); 2549 for (InnerClassesIterator iter(this); !iter.done(); iter.next()) { 2550 int ioff = iter.inner_class_info_index(); 2551 if (ioff != 0) { 2552 // Check to see if the name matches the class we're looking for 2553 // before attempting to find the class. 2554 if (i_cp->klass_name_at_matches(this, ioff)) { 2555 Klass* inner_klass = i_cp->klass_at(ioff, CHECK_false); 2556 if (this == inner_klass) { 2557 *ooff = iter.outer_class_info_index(); 2558 *noff = iter.inner_name_index(); 2559 return true; 2560 } 2561 } 2562 } 2563 } 2564 return false; 2565 } 2566 2567 InstanceKlass* InstanceKlass::compute_enclosing_class(bool* inner_is_member, TRAPS) const { 2568 InstanceKlass* outer_klass = NULL; 2569 *inner_is_member = false; 2570 int ooff = 0, noff = 0; 2571 bool has_inner_classes_attr = find_inner_classes_attr(&ooff, &noff, THREAD); 2572 if (has_inner_classes_attr) { 2573 constantPoolHandle i_cp(THREAD, constants()); 2574 if (ooff != 0) { 2575 Klass* ok = i_cp->klass_at(ooff, CHECK_NULL); 2576 outer_klass = InstanceKlass::cast(ok); 2577 *inner_is_member = true; 2578 } 2579 if (NULL == outer_klass) { 2580 // It may be anonymous; try for that. 2581 int encl_method_class_idx = enclosing_method_class_index(); 2582 if (encl_method_class_idx != 0) { 2583 Klass* ok = i_cp->klass_at(encl_method_class_idx, CHECK_NULL); 2584 outer_klass = InstanceKlass::cast(ok); 2585 *inner_is_member = false; 2586 } 2587 } 2588 } 2589 2590 // If no inner class attribute found for this class. 2591 if (NULL == outer_klass) return NULL; 2592 2593 // Throws an exception if outer klass has not declared k as an inner klass 2594 // We need evidence that each klass knows about the other, or else 2595 // the system could allow a spoof of an inner class to gain access rights. 2596 Reflection::check_for_inner_class(outer_klass, this, *inner_is_member, CHECK_NULL); 2597 return outer_klass; 2598 } 2599 2600 jint InstanceKlass::compute_modifier_flags(TRAPS) const { 2601 jint access = access_flags().as_int(); 2602 2603 // But check if it happens to be member class. 2604 InnerClassesIterator iter(this); 2605 for (; !iter.done(); iter.next()) { 2606 int ioff = iter.inner_class_info_index(); 2607 // Inner class attribute can be zero, skip it. 2608 // Strange but true: JVM spec. allows null inner class refs. 2609 if (ioff == 0) continue; 2610 2611 // only look at classes that are already loaded 2612 // since we are looking for the flags for our self. 2613 Symbol* inner_name = constants()->klass_name_at(ioff); 2614 if (name() == inner_name) { 2615 // This is really a member class. 2616 access = iter.inner_access_flags(); 2617 break; 2618 } 2619 } 2620 // Remember to strip ACC_SUPER bit 2621 return (access & (~JVM_ACC_SUPER)) & JVM_ACC_WRITTEN_FLAGS; 2622 } 2623 2624 jint InstanceKlass::jvmti_class_status() const { 2625 jint result = 0; 2626 2627 if (is_linked()) { 2628 result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED; 2629 } 2630 2631 if (is_initialized()) { 2632 assert(is_linked(), "Class status is not consistent"); 2633 result |= JVMTI_CLASS_STATUS_INITIALIZED; 2634 } 2635 if (is_in_error_state()) { 2636 result |= JVMTI_CLASS_STATUS_ERROR; 2637 } 2638 return result; 2639 } 2640 2641 Method* InstanceKlass::method_at_itable(Klass* holder, int index, TRAPS) { 2642 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable(); 2643 int method_table_offset_in_words = ioe->offset()/wordSize; 2644 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words()) 2645 / itableOffsetEntry::size(); 2646 2647 for (int cnt = 0 ; ; cnt ++, ioe ++) { 2648 // If the interface isn't implemented by the receiver class, 2649 // the VM should throw IncompatibleClassChangeError. 2650 if (cnt >= nof_interfaces) { 2651 THROW_NULL(vmSymbols::java_lang_IncompatibleClassChangeError()); 2652 } 2653 2654 Klass* ik = ioe->interface_klass(); 2655 if (ik == holder) break; 2656 } 2657 2658 itableMethodEntry* ime = ioe->first_method_entry(this); 2659 Method* m = ime[index].method(); 2660 if (m == NULL) { 2661 THROW_NULL(vmSymbols::java_lang_AbstractMethodError()); 2662 } 2663 return m; 2664 } 2665 2666 2667 #if INCLUDE_JVMTI 2668 // update default_methods for redefineclasses for methods that are 2669 // not yet in the vtable due to concurrent subclass define and superinterface 2670 // redefinition 2671 // Note: those in the vtable, should have been updated via adjust_method_entries 2672 void InstanceKlass::adjust_default_methods(InstanceKlass* holder, bool* trace_name_printed) { 2673 // search the default_methods for uses of either obsolete or EMCP methods 2674 if (default_methods() != NULL) { 2675 for (int index = 0; index < default_methods()->length(); index ++) { 2676 Method* old_method = default_methods()->at(index); 2677 if (old_method == NULL || old_method->method_holder() != holder || !old_method->is_old()) { 2678 continue; // skip uninteresting entries 2679 } 2680 assert(!old_method->is_deleted(), "default methods may not be deleted"); 2681 2682 Method* new_method = holder->method_with_idnum(old_method->orig_method_idnum()); 2683 2684 assert(new_method != NULL, "method_with_idnum() should not be NULL"); 2685 assert(old_method != new_method, "sanity check"); 2686 2687 default_methods()->at_put(index, new_method); 2688 if (log_is_enabled(Info, redefine, class, update)) { 2689 ResourceMark rm; 2690 if (!(*trace_name_printed)) { 2691 log_info(redefine, class, update) 2692 ("adjust: klassname=%s default methods from name=%s", 2693 external_name(), old_method->method_holder()->external_name()); 2694 *trace_name_printed = true; 2695 } 2696 log_debug(redefine, class, update, vtables) 2697 ("default method update: %s(%s) ", 2698 new_method->name()->as_C_string(), new_method->signature()->as_C_string()); 2699 } 2700 } 2701 } 2702 } 2703 #endif // INCLUDE_JVMTI 2704 2705 // On-stack replacement stuff 2706 void InstanceKlass::add_osr_nmethod(nmethod* n) { 2707 // only one compilation can be active 2708 { 2709 // This is a short non-blocking critical region, so the no safepoint check is ok. 2710 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag); 2711 assert(n->is_osr_method(), "wrong kind of nmethod"); 2712 n->set_osr_link(osr_nmethods_head()); 2713 set_osr_nmethods_head(n); 2714 // Raise the highest osr level if necessary 2715 if (TieredCompilation) { 2716 Method* m = n->method(); 2717 m->set_highest_osr_comp_level(MAX2(m->highest_osr_comp_level(), n->comp_level())); 2718 } 2719 } 2720 2721 // Get rid of the osr methods for the same bci that have lower levels. 2722 if (TieredCompilation) { 2723 for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) { 2724 nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true); 2725 if (inv != NULL && inv->is_in_use()) { 2726 inv->make_not_entrant(); 2727 } 2728 } 2729 } 2730 } 2731 2732 // Remove osr nmethod from the list. Return true if found and removed. 2733 bool InstanceKlass::remove_osr_nmethod(nmethod* n) { 2734 // This is a short non-blocking critical region, so the no safepoint check is ok. 2735 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag); 2736 assert(n->is_osr_method(), "wrong kind of nmethod"); 2737 nmethod* last = NULL; 2738 nmethod* cur = osr_nmethods_head(); 2739 int max_level = CompLevel_none; // Find the max comp level excluding n 2740 Method* m = n->method(); 2741 // Search for match 2742 bool found = false; 2743 while(cur != NULL && cur != n) { 2744 if (TieredCompilation && m == cur->method()) { 2745 // Find max level before n 2746 max_level = MAX2(max_level, cur->comp_level()); 2747 } 2748 last = cur; 2749 cur = cur->osr_link(); 2750 } 2751 nmethod* next = NULL; 2752 if (cur == n) { 2753 found = true; 2754 next = cur->osr_link(); 2755 if (last == NULL) { 2756 // Remove first element 2757 set_osr_nmethods_head(next); 2758 } else { 2759 last->set_osr_link(next); 2760 } 2761 } 2762 n->set_osr_link(NULL); 2763 if (TieredCompilation) { 2764 cur = next; 2765 while (cur != NULL) { 2766 // Find max level after n 2767 if (m == cur->method()) { 2768 max_level = MAX2(max_level, cur->comp_level()); 2769 } 2770 cur = cur->osr_link(); 2771 } 2772 m->set_highest_osr_comp_level(max_level); 2773 } 2774 return found; 2775 } 2776 2777 int InstanceKlass::mark_osr_nmethods(const Method* m) { 2778 // This is a short non-blocking critical region, so the no safepoint check is ok. 2779 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag); 2780 nmethod* osr = osr_nmethods_head(); 2781 int found = 0; 2782 while (osr != NULL) { 2783 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain"); 2784 if (osr->method() == m) { 2785 osr->mark_for_deoptimization(); 2786 found++; 2787 } 2788 osr = osr->osr_link(); 2789 } 2790 return found; 2791 } 2792 2793 nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const { 2794 // This is a short non-blocking critical region, so the no safepoint check is ok. 2795 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag); 2796 nmethod* osr = osr_nmethods_head(); 2797 nmethod* best = NULL; 2798 while (osr != NULL) { 2799 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain"); 2800 // There can be a time when a c1 osr method exists but we are waiting 2801 // for a c2 version. When c2 completes its osr nmethod we will trash 2802 // the c1 version and only be able to find the c2 version. However 2803 // while we overflow in the c1 code at back branches we don't want to 2804 // try and switch to the same code as we are already running 2805 2806 if (osr->method() == m && 2807 (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) { 2808 if (match_level) { 2809 if (osr->comp_level() == comp_level) { 2810 // Found a match - return it. 2811 return osr; 2812 } 2813 } else { 2814 if (best == NULL || (osr->comp_level() > best->comp_level())) { 2815 if (osr->comp_level() == CompLevel_highest_tier) { 2816 // Found the best possible - return it. 2817 return osr; 2818 } 2819 best = osr; 2820 } 2821 } 2822 } 2823 osr = osr->osr_link(); 2824 } 2825 if (best != NULL && best->comp_level() >= comp_level && match_level == false) { 2826 return best; 2827 } 2828 return NULL; 2829 } 2830 2831 // ----------------------------------------------------------------------------------------------------- 2832 // Printing 2833 2834 #ifndef PRODUCT 2835 2836 #define BULLET " - " 2837 2838 static const char* state_names[] = { 2839 "allocated", "loaded", "linked", "being_initialized", "fully_initialized", "initialization_error" 2840 }; 2841 2842 static void print_vtable(intptr_t* start, int len, outputStream* st) { 2843 for (int i = 0; i < len; i++) { 2844 intptr_t e = start[i]; 2845 st->print("%d : " INTPTR_FORMAT, i, e); 2846 if (e != 0 && ((Metadata*)e)->is_metaspace_object()) { 2847 st->print(" "); 2848 ((Metadata*)e)->print_value_on(st); 2849 } 2850 st->cr(); 2851 } 2852 } 2853 2854 static void print_vtable(vtableEntry* start, int len, outputStream* st) { 2855 return print_vtable(reinterpret_cast<intptr_t*>(start), len, st); 2856 } 2857 2858 void InstanceKlass::print_on(outputStream* st) const { 2859 assert(is_klass(), "must be klass"); 2860 Klass::print_on(st); 2861 2862 st->print(BULLET"instance size: %d", size_helper()); st->cr(); 2863 st->print(BULLET"klass size: %d", size()); st->cr(); 2864 st->print(BULLET"access: "); access_flags().print_on(st); st->cr(); 2865 st->print(BULLET"state: "); st->print_cr("%s", state_names[_init_state]); 2866 st->print(BULLET"name: "); name()->print_value_on(st); st->cr(); 2867 st->print(BULLET"super: "); super()->print_value_on_maybe_null(st); st->cr(); 2868 st->print(BULLET"sub: "); 2869 Klass* sub = subklass(); 2870 int n; 2871 for (n = 0; sub != NULL; n++, sub = sub->next_sibling()) { 2872 if (n < MaxSubklassPrintSize) { 2873 sub->print_value_on(st); 2874 st->print(" "); 2875 } 2876 } 2877 if (n >= MaxSubklassPrintSize) st->print("(" INTX_FORMAT " more klasses...)", n - MaxSubklassPrintSize); 2878 st->cr(); 2879 2880 if (is_interface()) { 2881 st->print_cr(BULLET"nof implementors: %d", nof_implementors()); 2882 if (nof_implementors() == 1) { 2883 st->print_cr(BULLET"implementor: "); 2884 st->print(" "); 2885 implementor()->print_value_on(st); 2886 st->cr(); 2887 } 2888 } 2889 2890 st->print(BULLET"arrays: "); array_klasses()->print_value_on_maybe_null(st); st->cr(); 2891 st->print(BULLET"methods: "); methods()->print_value_on(st); st->cr(); 2892 if (Verbose || WizardMode) { 2893 Array<Method*>* method_array = methods(); 2894 for (int i = 0; i < method_array->length(); i++) { 2895 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr(); 2896 } 2897 } 2898 st->print(BULLET"method ordering: "); method_ordering()->print_value_on(st); st->cr(); 2899 st->print(BULLET"default_methods: "); default_methods()->print_value_on(st); st->cr(); 2900 if (Verbose && default_methods() != NULL) { 2901 Array<Method*>* method_array = default_methods(); 2902 for (int i = 0; i < method_array->length(); i++) { 2903 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr(); 2904 } 2905 } 2906 if (default_vtable_indices() != NULL) { 2907 st->print(BULLET"default vtable indices: "); default_vtable_indices()->print_value_on(st); st->cr(); 2908 } 2909 st->print(BULLET"local interfaces: "); local_interfaces()->print_value_on(st); st->cr(); 2910 st->print(BULLET"trans. interfaces: "); transitive_interfaces()->print_value_on(st); st->cr(); 2911 st->print(BULLET"constants: "); constants()->print_value_on(st); st->cr(); 2912 if (class_loader_data() != NULL) { 2913 st->print(BULLET"class loader data: "); 2914 class_loader_data()->print_value_on(st); 2915 st->cr(); 2916 } 2917 st->print(BULLET"host class: "); host_klass()->print_value_on_maybe_null(st); st->cr(); 2918 if (source_file_name() != NULL) { 2919 st->print(BULLET"source file: "); 2920 source_file_name()->print_value_on(st); 2921 st->cr(); 2922 } 2923 if (source_debug_extension() != NULL) { 2924 st->print(BULLET"source debug extension: "); 2925 st->print("%s", source_debug_extension()); 2926 st->cr(); 2927 } 2928 st->print(BULLET"class annotations: "); class_annotations()->print_value_on(st); st->cr(); 2929 st->print(BULLET"class type annotations: "); class_type_annotations()->print_value_on(st); st->cr(); 2930 st->print(BULLET"field annotations: "); fields_annotations()->print_value_on(st); st->cr(); 2931 st->print(BULLET"field type annotations: "); fields_type_annotations()->print_value_on(st); st->cr(); 2932 { 2933 bool have_pv = false; 2934 // previous versions are linked together through the InstanceKlass 2935 for (InstanceKlass* pv_node = previous_versions(); 2936 pv_node != NULL; 2937 pv_node = pv_node->previous_versions()) { 2938 if (!have_pv) 2939 st->print(BULLET"previous version: "); 2940 have_pv = true; 2941 pv_node->constants()->print_value_on(st); 2942 } 2943 if (have_pv) st->cr(); 2944 } 2945 2946 if (generic_signature() != NULL) { 2947 st->print(BULLET"generic signature: "); 2948 generic_signature()->print_value_on(st); 2949 st->cr(); 2950 } 2951 st->print(BULLET"inner classes: "); inner_classes()->print_value_on(st); st->cr(); 2952 st->print(BULLET"java mirror: "); java_mirror()->print_value_on(st); st->cr(); 2953 st->print(BULLET"vtable length %d (start addr: " INTPTR_FORMAT ")", vtable_length(), p2i(start_of_vtable())); st->cr(); 2954 if (vtable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_vtable(), vtable_length(), st); 2955 st->print(BULLET"itable length %d (start addr: " INTPTR_FORMAT ")", itable_length(), p2i(start_of_itable())); st->cr(); 2956 if (itable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_itable(), itable_length(), st); 2957 st->print_cr(BULLET"---- static fields (%d words):", static_field_size()); 2958 FieldPrinter print_static_field(st); 2959 ((InstanceKlass*)this)->do_local_static_fields(&print_static_field); 2960 st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size()); 2961 FieldPrinter print_nonstatic_field(st); 2962 InstanceKlass* ik = const_cast<InstanceKlass*>(this); 2963 ik->do_nonstatic_fields(&print_nonstatic_field); 2964 2965 st->print(BULLET"non-static oop maps: "); 2966 OopMapBlock* map = start_of_nonstatic_oop_maps(); 2967 OopMapBlock* end_map = map + nonstatic_oop_map_count(); 2968 while (map < end_map) { 2969 st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1)); 2970 map++; 2971 } 2972 st->cr(); 2973 } 2974 2975 #endif //PRODUCT 2976 2977 void InstanceKlass::print_value_on(outputStream* st) const { 2978 assert(is_klass(), "must be klass"); 2979 if (Verbose || WizardMode) access_flags().print_on(st); 2980 name()->print_value_on(st); 2981 } 2982 2983 #ifndef PRODUCT 2984 2985 void FieldPrinter::do_field(fieldDescriptor* fd) { 2986 _st->print(BULLET); 2987 if (_obj == NULL) { 2988 fd->print_on(_st); 2989 _st->cr(); 2990 } else { 2991 fd->print_on_for(_st, _obj); 2992 _st->cr(); 2993 } 2994 } 2995 2996 2997 void InstanceKlass::oop_print_on(oop obj, outputStream* st) { 2998 Klass::oop_print_on(obj, st); 2999 3000 if (this == SystemDictionary::String_klass()) { 3001 typeArrayOop value = java_lang_String::value(obj); 3002 juint length = java_lang_String::length(obj); 3003 if (value != NULL && 3004 value->is_typeArray() && 3005 length <= (juint) value->length()) { 3006 st->print(BULLET"string: "); 3007 java_lang_String::print(obj, st); 3008 st->cr(); 3009 if (!WizardMode) return; // that is enough 3010 } 3011 } 3012 3013 st->print_cr(BULLET"---- fields (total size %d words):", oop_size(obj)); 3014 FieldPrinter print_field(st, obj); 3015 do_nonstatic_fields(&print_field); 3016 3017 if (this == SystemDictionary::Class_klass()) { 3018 st->print(BULLET"signature: "); 3019 java_lang_Class::print_signature(obj, st); 3020 st->cr(); 3021 Klass* mirrored_klass = java_lang_Class::as_Klass(obj); 3022 st->print(BULLET"fake entry for mirror: "); 3023 mirrored_klass->print_value_on_maybe_null(st); 3024 st->cr(); 3025 Klass* array_klass = java_lang_Class::array_klass_acquire(obj); 3026 st->print(BULLET"fake entry for array: "); 3027 array_klass->print_value_on_maybe_null(st); 3028 st->cr(); 3029 st->print_cr(BULLET"fake entry for oop_size: %d", java_lang_Class::oop_size(obj)); 3030 st->print_cr(BULLET"fake entry for static_oop_field_count: %d", java_lang_Class::static_oop_field_count(obj)); 3031 Klass* real_klass = java_lang_Class::as_Klass(obj); 3032 if (real_klass != NULL && real_klass->is_instance_klass()) { 3033 InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field); 3034 } 3035 } else if (this == SystemDictionary::MethodType_klass()) { 3036 st->print(BULLET"signature: "); 3037 java_lang_invoke_MethodType::print_signature(obj, st); 3038 st->cr(); 3039 } 3040 } 3041 3042 #endif //PRODUCT 3043 3044 void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) { 3045 st->print("a "); 3046 name()->print_value_on(st); 3047 obj->print_address_on(st); 3048 if (this == SystemDictionary::String_klass() 3049 && java_lang_String::value(obj) != NULL) { 3050 ResourceMark rm; 3051 int len = java_lang_String::length(obj); 3052 int plen = (len < 24 ? len : 12); 3053 char* str = java_lang_String::as_utf8_string(obj, 0, plen); 3054 st->print(" = \"%s\"", str); 3055 if (len > plen) 3056 st->print("...[%d]", len); 3057 } else if (this == SystemDictionary::Class_klass()) { 3058 Klass* k = java_lang_Class::as_Klass(obj); 3059 st->print(" = "); 3060 if (k != NULL) { 3061 k->print_value_on(st); 3062 } else { 3063 const char* tname = type2name(java_lang_Class::primitive_type(obj)); 3064 st->print("%s", tname ? tname : "type?"); 3065 } 3066 } else if (this == SystemDictionary::MethodType_klass()) { 3067 st->print(" = "); 3068 java_lang_invoke_MethodType::print_signature(obj, st); 3069 } else if (java_lang_boxing_object::is_instance(obj)) { 3070 st->print(" = "); 3071 java_lang_boxing_object::print(obj, st); 3072 } else if (this == SystemDictionary::LambdaForm_klass()) { 3073 oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj); 3074 if (vmentry != NULL) { 3075 st->print(" => "); 3076 vmentry->print_value_on(st); 3077 } 3078 } else if (this == SystemDictionary::MemberName_klass()) { 3079 Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj); 3080 if (vmtarget != NULL) { 3081 st->print(" = "); 3082 vmtarget->print_value_on(st); 3083 } else { 3084 java_lang_invoke_MemberName::clazz(obj)->print_value_on(st); 3085 st->print("."); 3086 java_lang_invoke_MemberName::name(obj)->print_value_on(st); 3087 } 3088 } 3089 } 3090 3091 const char* InstanceKlass::internal_name() const { 3092 return external_name(); 3093 } 3094 3095 void InstanceKlass::print_class_load_logging(ClassLoaderData* loader_data, 3096 const char* module_name, 3097 const ClassFileStream* cfs) const { 3098 if (!log_is_enabled(Info, class, load)) { 3099 return; 3100 } 3101 3102 ResourceMark rm; 3103 LogMessage(class, load) msg; 3104 stringStream info_stream; 3105 3106 // Name and class hierarchy info 3107 info_stream.print("%s", external_name()); 3108 3109 // Source 3110 if (cfs != NULL) { 3111 if (cfs->source() != NULL) { 3112 if (module_name != NULL) { 3113 if (ClassLoader::is_jrt(cfs->source())) { 3114 info_stream.print(" source: jrt:/%s", module_name); 3115 } else { 3116 info_stream.print(" source: %s", cfs->source()); 3117 } 3118 } else { 3119 info_stream.print(" source: %s", cfs->source()); 3120 } 3121 } else if (loader_data == ClassLoaderData::the_null_class_loader_data()) { 3122 Thread* THREAD = Thread::current(); 3123 Klass* caller = 3124 THREAD->is_Java_thread() 3125 ? ((JavaThread*)THREAD)->security_get_caller_class(1) 3126 : NULL; 3127 // caller can be NULL, for example, during a JVMTI VM_Init hook 3128 if (caller != NULL) { 3129 info_stream.print(" source: instance of %s", caller->external_name()); 3130 } else { 3131 // source is unknown 3132 } 3133 } else { 3134 oop class_loader = loader_data->class_loader(); 3135 info_stream.print(" source: %s", class_loader->klass()->external_name()); 3136 } 3137 } else { 3138 info_stream.print(" source: shared objects file"); 3139 } 3140 3141 msg.info("%s", info_stream.as_string()); 3142 3143 if (log_is_enabled(Debug, class, load)) { 3144 stringStream debug_stream; 3145 3146 // Class hierarchy info 3147 debug_stream.print(" klass: " INTPTR_FORMAT " super: " INTPTR_FORMAT, 3148 p2i(this), p2i(superklass())); 3149 3150 // Interfaces 3151 if (local_interfaces() != NULL && local_interfaces()->length() > 0) { 3152 debug_stream.print(" interfaces:"); 3153 int length = local_interfaces()->length(); 3154 for (int i = 0; i < length; i++) { 3155 debug_stream.print(" " INTPTR_FORMAT, 3156 p2i(InstanceKlass::cast(local_interfaces()->at(i)))); 3157 } 3158 } 3159 3160 // Class loader 3161 debug_stream.print(" loader: ["); 3162 loader_data->print_value_on(&debug_stream); 3163 debug_stream.print("]"); 3164 3165 // Classfile checksum 3166 if (cfs) { 3167 debug_stream.print(" bytes: %d checksum: %08x", 3168 cfs->length(), 3169 ClassLoader::crc32(0, (const char*)cfs->buffer(), 3170 cfs->length())); 3171 } 3172 3173 msg.debug("%s", debug_stream.as_string()); 3174 } 3175 } 3176 3177 #if INCLUDE_SERVICES 3178 // Size Statistics 3179 void InstanceKlass::collect_statistics(KlassSizeStats *sz) const { 3180 Klass::collect_statistics(sz); 3181 3182 sz->_inst_size = wordSize * size_helper(); 3183 sz->_vtab_bytes = wordSize * vtable_length(); 3184 sz->_itab_bytes = wordSize * itable_length(); 3185 sz->_nonstatic_oopmap_bytes = wordSize * nonstatic_oop_map_size(); 3186 3187 int n = 0; 3188 n += (sz->_methods_array_bytes = sz->count_array(methods())); 3189 n += (sz->_method_ordering_bytes = sz->count_array(method_ordering())); 3190 n += (sz->_local_interfaces_bytes = sz->count_array(local_interfaces())); 3191 n += (sz->_transitive_interfaces_bytes = sz->count_array(transitive_interfaces())); 3192 n += (sz->_fields_bytes = sz->count_array(fields())); 3193 n += (sz->_inner_classes_bytes = sz->count_array(inner_classes())); 3194 sz->_ro_bytes += n; 3195 3196 const ConstantPool* cp = constants(); 3197 if (cp) { 3198 cp->collect_statistics(sz); 3199 } 3200 3201 const Annotations* anno = annotations(); 3202 if (anno) { 3203 anno->collect_statistics(sz); 3204 } 3205 3206 const Array<Method*>* methods_array = methods(); 3207 if (methods()) { 3208 for (int i = 0; i < methods_array->length(); i++) { 3209 Method* method = methods_array->at(i); 3210 if (method) { 3211 sz->_method_count ++; 3212 method->collect_statistics(sz); 3213 } 3214 } 3215 } 3216 } 3217 #endif // INCLUDE_SERVICES 3218 3219 // Verification 3220 3221 class VerifyFieldClosure: public OopClosure { 3222 protected: 3223 template <class T> void do_oop_work(T* p) { 3224 oop obj = oopDesc::load_decode_heap_oop(p); 3225 if (!oopDesc::is_oop_or_null(obj)) { 3226 tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p2i(p), p2i(obj)); 3227 Universe::print_on(tty); 3228 guarantee(false, "boom"); 3229 } 3230 } 3231 public: 3232 virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); } 3233 virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); } 3234 }; 3235 3236 void InstanceKlass::verify_on(outputStream* st) { 3237 #ifndef PRODUCT 3238 // Avoid redundant verifies, this really should be in product. 3239 if (_verify_count == Universe::verify_count()) return; 3240 _verify_count = Universe::verify_count(); 3241 #endif 3242 3243 // Verify Klass 3244 Klass::verify_on(st); 3245 3246 // Verify that klass is present in ClassLoaderData 3247 guarantee(class_loader_data()->contains_klass(this), 3248 "this class isn't found in class loader data"); 3249 3250 // Verify vtables 3251 if (is_linked()) { 3252 // $$$ This used to be done only for m/s collections. Doing it 3253 // always seemed a valid generalization. (DLD -- 6/00) 3254 vtable().verify(st); 3255 } 3256 3257 // Verify first subklass 3258 if (subklass() != NULL) { 3259 guarantee(subklass()->is_klass(), "should be klass"); 3260 } 3261 3262 // Verify siblings 3263 Klass* super = this->super(); 3264 Klass* sib = next_sibling(); 3265 if (sib != NULL) { 3266 if (sib == this) { 3267 fatal("subclass points to itself " PTR_FORMAT, p2i(sib)); 3268 } 3269 3270 guarantee(sib->is_klass(), "should be klass"); 3271 guarantee(sib->super() == super, "siblings should have same superklass"); 3272 } 3273 3274 // Verify implementor fields 3275 Klass* im = implementor(); 3276 if (im != NULL) { 3277 guarantee(is_interface(), "only interfaces should have implementor set"); 3278 guarantee(im->is_klass(), "should be klass"); 3279 guarantee(!im->is_interface() || im == this, 3280 "implementors cannot be interfaces"); 3281 } 3282 3283 // Verify local interfaces 3284 if (local_interfaces()) { 3285 Array<Klass*>* local_interfaces = this->local_interfaces(); 3286 for (int j = 0; j < local_interfaces->length(); j++) { 3287 Klass* e = local_interfaces->at(j); 3288 guarantee(e->is_klass() && e->is_interface(), "invalid local interface"); 3289 } 3290 } 3291 3292 // Verify transitive interfaces 3293 if (transitive_interfaces() != NULL) { 3294 Array<Klass*>* transitive_interfaces = this->transitive_interfaces(); 3295 for (int j = 0; j < transitive_interfaces->length(); j++) { 3296 Klass* e = transitive_interfaces->at(j); 3297 guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface"); 3298 } 3299 } 3300 3301 // Verify methods 3302 if (methods() != NULL) { 3303 Array<Method*>* methods = this->methods(); 3304 for (int j = 0; j < methods->length(); j++) { 3305 guarantee(methods->at(j)->is_method(), "non-method in methods array"); 3306 } 3307 for (int j = 0; j < methods->length() - 1; j++) { 3308 Method* m1 = methods->at(j); 3309 Method* m2 = methods->at(j + 1); 3310 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly"); 3311 } 3312 } 3313 3314 // Verify method ordering 3315 if (method_ordering() != NULL) { 3316 Array<int>* method_ordering = this->method_ordering(); 3317 int length = method_ordering->length(); 3318 if (JvmtiExport::can_maintain_original_method_order() || 3319 ((UseSharedSpaces || DumpSharedSpaces) && length != 0)) { 3320 guarantee(length == methods()->length(), "invalid method ordering length"); 3321 jlong sum = 0; 3322 for (int j = 0; j < length; j++) { 3323 int original_index = method_ordering->at(j); 3324 guarantee(original_index >= 0, "invalid method ordering index"); 3325 guarantee(original_index < length, "invalid method ordering index"); 3326 sum += original_index; 3327 } 3328 // Verify sum of indices 0,1,...,length-1 3329 guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum"); 3330 } else { 3331 guarantee(length == 0, "invalid method ordering length"); 3332 } 3333 } 3334 3335 // Verify default methods 3336 if (default_methods() != NULL) { 3337 Array<Method*>* methods = this->default_methods(); 3338 for (int j = 0; j < methods->length(); j++) { 3339 guarantee(methods->at(j)->is_method(), "non-method in methods array"); 3340 } 3341 for (int j = 0; j < methods->length() - 1; j++) { 3342 Method* m1 = methods->at(j); 3343 Method* m2 = methods->at(j + 1); 3344 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly"); 3345 } 3346 } 3347 3348 // Verify JNI static field identifiers 3349 if (jni_ids() != NULL) { 3350 jni_ids()->verify(this); 3351 } 3352 3353 // Verify other fields 3354 if (array_klasses() != NULL) { 3355 guarantee(array_klasses()->is_klass(), "should be klass"); 3356 } 3357 if (constants() != NULL) { 3358 guarantee(constants()->is_constantPool(), "should be constant pool"); 3359 } 3360 const Klass* host = host_klass(); 3361 if (host != NULL) { 3362 guarantee(host->is_klass(), "should be klass"); 3363 } 3364 } 3365 3366 void InstanceKlass::oop_verify_on(oop obj, outputStream* st) { 3367 Klass::oop_verify_on(obj, st); 3368 VerifyFieldClosure blk; 3369 obj->oop_iterate_no_header(&blk); 3370 } 3371 3372 3373 // JNIid class for jfieldIDs only 3374 // Note to reviewers: 3375 // These JNI functions are just moved over to column 1 and not changed 3376 // in the compressed oops workspace. 3377 JNIid::JNIid(Klass* holder, int offset, JNIid* next) { 3378 _holder = holder; 3379 _offset = offset; 3380 _next = next; 3381 debug_only(_is_static_field_id = false;) 3382 } 3383 3384 3385 JNIid* JNIid::find(int offset) { 3386 JNIid* current = this; 3387 while (current != NULL) { 3388 if (current->offset() == offset) return current; 3389 current = current->next(); 3390 } 3391 return NULL; 3392 } 3393 3394 void JNIid::deallocate(JNIid* current) { 3395 while (current != NULL) { 3396 JNIid* next = current->next(); 3397 delete current; 3398 current = next; 3399 } 3400 } 3401 3402 3403 void JNIid::verify(Klass* holder) { 3404 int first_field_offset = InstanceMirrorKlass::offset_of_static_fields(); 3405 int end_field_offset; 3406 end_field_offset = first_field_offset + (InstanceKlass::cast(holder)->static_field_size() * wordSize); 3407 3408 JNIid* current = this; 3409 while (current != NULL) { 3410 guarantee(current->holder() == holder, "Invalid klass in JNIid"); 3411 #ifdef ASSERT 3412 int o = current->offset(); 3413 if (current->is_static_field_id()) { 3414 guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid"); 3415 } 3416 #endif 3417 current = current->next(); 3418 } 3419 } 3420 3421 3422 #ifdef ASSERT 3423 void InstanceKlass::set_init_state(ClassState state) { 3424 bool good_state = is_shared() ? (_init_state <= state) 3425 : (_init_state < state); 3426 assert(good_state || state == allocated, "illegal state transition"); 3427 _init_state = (u1)state; 3428 } 3429 #endif 3430 3431 #if INCLUDE_JVMTI 3432 3433 // RedefineClasses() support for previous versions 3434 3435 // Globally, there is at least one previous version of a class to walk 3436 // during class unloading, which is saved because old methods in the class 3437 // are still running. Otherwise the previous version list is cleaned up. 3438 bool InstanceKlass::_has_previous_versions = false; 3439 3440 // Returns true if there are previous versions of a class for class 3441 // unloading only. Also resets the flag to false. purge_previous_version 3442 // will set the flag to true if there are any left, i.e., if there's any 3443 // work to do for next time. This is to avoid the expensive code cache 3444 // walk in CLDG::do_unloading(). 3445 bool InstanceKlass::has_previous_versions_and_reset() { 3446 bool ret = _has_previous_versions; 3447 log_trace(redefine, class, iklass, purge)("Class unloading: has_previous_versions = %s", 3448 ret ? "true" : "false"); 3449 _has_previous_versions = false; 3450 return ret; 3451 } 3452 3453 // Purge previous versions before adding new previous versions of the class and 3454 // during class unloading. 3455 void InstanceKlass::purge_previous_version_list() { 3456 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint"); 3457 assert(has_been_redefined(), "Should only be called for main class"); 3458 3459 // Quick exit. 3460 if (previous_versions() == NULL) { 3461 return; 3462 } 3463 3464 // This klass has previous versions so see what we can cleanup 3465 // while it is safe to do so. 3466 3467 int deleted_count = 0; // leave debugging breadcrumbs 3468 int live_count = 0; 3469 ClassLoaderData* loader_data = class_loader_data(); 3470 assert(loader_data != NULL, "should never be null"); 3471 3472 ResourceMark rm; 3473 log_trace(redefine, class, iklass, purge)("%s: previous versions", external_name()); 3474 3475 // previous versions are linked together through the InstanceKlass 3476 InstanceKlass* pv_node = previous_versions(); 3477 InstanceKlass* last = this; 3478 int version = 0; 3479 3480 // check the previous versions list 3481 for (; pv_node != NULL; ) { 3482 3483 ConstantPool* pvcp = pv_node->constants(); 3484 assert(pvcp != NULL, "cp ref was unexpectedly cleared"); 3485 3486 if (!pvcp->on_stack()) { 3487 // If the constant pool isn't on stack, none of the methods 3488 // are executing. Unlink this previous_version. 3489 // The previous version InstanceKlass is on the ClassLoaderData deallocate list 3490 // so will be deallocated during the next phase of class unloading. 3491 log_trace(redefine, class, iklass, purge) 3492 ("previous version " INTPTR_FORMAT " is dead.", p2i(pv_node)); 3493 // For debugging purposes. 3494 pv_node->set_is_scratch_class(); 3495 // Unlink from previous version list. 3496 assert(pv_node->class_loader_data() == loader_data, "wrong loader_data"); 3497 InstanceKlass* next = pv_node->previous_versions(); 3498 pv_node->link_previous_versions(NULL); // point next to NULL 3499 last->link_previous_versions(next); 3500 // Add to the deallocate list after unlinking 3501 loader_data->add_to_deallocate_list(pv_node); 3502 pv_node = next; 3503 deleted_count++; 3504 version++; 3505 continue; 3506 } else { 3507 log_trace(redefine, class, iklass, purge)("previous version " INTPTR_FORMAT " is alive", p2i(pv_node)); 3508 assert(pvcp->pool_holder() != NULL, "Constant pool with no holder"); 3509 guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack"); 3510 live_count++; 3511 // found a previous version for next time we do class unloading 3512 _has_previous_versions = true; 3513 } 3514 3515 // At least one method is live in this previous version. 3516 // Reset dead EMCP methods not to get breakpoints. 3517 // All methods are deallocated when all of the methods for this class are no 3518 // longer running. 3519 Array<Method*>* method_refs = pv_node->methods(); 3520 if (method_refs != NULL) { 3521 log_trace(redefine, class, iklass, purge)("previous methods length=%d", method_refs->length()); 3522 for (int j = 0; j < method_refs->length(); j++) { 3523 Method* method = method_refs->at(j); 3524 3525 if (!method->on_stack()) { 3526 // no breakpoints for non-running methods 3527 if (method->is_running_emcp()) { 3528 method->set_running_emcp(false); 3529 } 3530 } else { 3531 assert (method->is_obsolete() || method->is_running_emcp(), 3532 "emcp method cannot run after emcp bit is cleared"); 3533 log_trace(redefine, class, iklass, purge) 3534 ("purge: %s(%s): prev method @%d in version @%d is alive", 3535 method->name()->as_C_string(), method->signature()->as_C_string(), j, version); 3536 } 3537 } 3538 } 3539 // next previous version 3540 last = pv_node; 3541 pv_node = pv_node->previous_versions(); 3542 version++; 3543 } 3544 log_trace(redefine, class, iklass, purge) 3545 ("previous version stats: live=%d, deleted=%d", live_count, deleted_count); 3546 } 3547 3548 void InstanceKlass::mark_newly_obsolete_methods(Array<Method*>* old_methods, 3549 int emcp_method_count) { 3550 int obsolete_method_count = old_methods->length() - emcp_method_count; 3551 3552 if (emcp_method_count != 0 && obsolete_method_count != 0 && 3553 _previous_versions != NULL) { 3554 // We have a mix of obsolete and EMCP methods so we have to 3555 // clear out any matching EMCP method entries the hard way. 3556 int local_count = 0; 3557 for (int i = 0; i < old_methods->length(); i++) { 3558 Method* old_method = old_methods->at(i); 3559 if (old_method->is_obsolete()) { 3560 // only obsolete methods are interesting 3561 Symbol* m_name = old_method->name(); 3562 Symbol* m_signature = old_method->signature(); 3563 3564 // previous versions are linked together through the InstanceKlass 3565 int j = 0; 3566 for (InstanceKlass* prev_version = _previous_versions; 3567 prev_version != NULL; 3568 prev_version = prev_version->previous_versions(), j++) { 3569 3570 Array<Method*>* method_refs = prev_version->methods(); 3571 for (int k = 0; k < method_refs->length(); k++) { 3572 Method* method = method_refs->at(k); 3573 3574 if (!method->is_obsolete() && 3575 method->name() == m_name && 3576 method->signature() == m_signature) { 3577 // The current RedefineClasses() call has made all EMCP 3578 // versions of this method obsolete so mark it as obsolete 3579 log_trace(redefine, class, iklass, add) 3580 ("%s(%s): flush obsolete method @%d in version @%d", 3581 m_name->as_C_string(), m_signature->as_C_string(), k, j); 3582 3583 method->set_is_obsolete(); 3584 break; 3585 } 3586 } 3587 3588 // The previous loop may not find a matching EMCP method, but 3589 // that doesn't mean that we can optimize and not go any 3590 // further back in the PreviousVersion generations. The EMCP 3591 // method for this generation could have already been made obsolete, 3592 // but there still may be an older EMCP method that has not 3593 // been made obsolete. 3594 } 3595 3596 if (++local_count >= obsolete_method_count) { 3597 // no more obsolete methods so bail out now 3598 break; 3599 } 3600 } 3601 } 3602 } 3603 } 3604 3605 // Save the scratch_class as the previous version if any of the methods are running. 3606 // The previous_versions are used to set breakpoints in EMCP methods and they are 3607 // also used to clean MethodData links to redefined methods that are no longer running. 3608 void InstanceKlass::add_previous_version(InstanceKlass* scratch_class, 3609 int emcp_method_count) { 3610 assert(Thread::current()->is_VM_thread(), 3611 "only VMThread can add previous versions"); 3612 3613 ResourceMark rm; 3614 log_trace(redefine, class, iklass, add) 3615 ("adding previous version ref for %s, EMCP_cnt=%d", scratch_class->external_name(), emcp_method_count); 3616 3617 // Clean out old previous versions for this class 3618 purge_previous_version_list(); 3619 3620 // Mark newly obsolete methods in remaining previous versions. An EMCP method from 3621 // a previous redefinition may be made obsolete by this redefinition. 3622 Array<Method*>* old_methods = scratch_class->methods(); 3623 mark_newly_obsolete_methods(old_methods, emcp_method_count); 3624 3625 // If the constant pool for this previous version of the class 3626 // is not marked as being on the stack, then none of the methods 3627 // in this previous version of the class are on the stack so 3628 // we don't need to add this as a previous version. 3629 ConstantPool* cp_ref = scratch_class->constants(); 3630 if (!cp_ref->on_stack()) { 3631 log_trace(redefine, class, iklass, add)("scratch class not added; no methods are running"); 3632 // For debugging purposes. 3633 scratch_class->set_is_scratch_class(); 3634 scratch_class->class_loader_data()->add_to_deallocate_list(scratch_class); 3635 return; 3636 } 3637 3638 if (emcp_method_count != 0) { 3639 // At least one method is still running, check for EMCP methods 3640 for (int i = 0; i < old_methods->length(); i++) { 3641 Method* old_method = old_methods->at(i); 3642 if (!old_method->is_obsolete() && old_method->on_stack()) { 3643 // if EMCP method (not obsolete) is on the stack, mark as EMCP so that 3644 // we can add breakpoints for it. 3645 3646 // We set the method->on_stack bit during safepoints for class redefinition 3647 // and use this bit to set the is_running_emcp bit. 3648 // After the safepoint, the on_stack bit is cleared and the running emcp 3649 // method may exit. If so, we would set a breakpoint in a method that 3650 // is never reached, but this won't be noticeable to the programmer. 3651 old_method->set_running_emcp(true); 3652 log_trace(redefine, class, iklass, add) 3653 ("EMCP method %s is on_stack " INTPTR_FORMAT, old_method->name_and_sig_as_C_string(), p2i(old_method)); 3654 } else if (!old_method->is_obsolete()) { 3655 log_trace(redefine, class, iklass, add) 3656 ("EMCP method %s is NOT on_stack " INTPTR_FORMAT, old_method->name_and_sig_as_C_string(), p2i(old_method)); 3657 } 3658 } 3659 } 3660 3661 // Add previous version if any methods are still running. 3662 // Set has_previous_version flag for processing during class unloading. 3663 _has_previous_versions = true; 3664 log_trace(redefine, class, iklass, add) ("scratch class added; one of its methods is on_stack."); 3665 assert(scratch_class->previous_versions() == NULL, "shouldn't have a previous version"); 3666 scratch_class->link_previous_versions(previous_versions()); 3667 link_previous_versions(scratch_class); 3668 } // end add_previous_version() 3669 3670 #endif // INCLUDE_JVMTI 3671 3672 Method* InstanceKlass::method_with_idnum(int idnum) { 3673 Method* m = NULL; 3674 if (idnum < methods()->length()) { 3675 m = methods()->at(idnum); 3676 } 3677 if (m == NULL || m->method_idnum() != idnum) { 3678 for (int index = 0; index < methods()->length(); ++index) { 3679 m = methods()->at(index); 3680 if (m->method_idnum() == idnum) { 3681 return m; 3682 } 3683 } 3684 // None found, return null for the caller to handle. 3685 return NULL; 3686 } 3687 return m; 3688 } 3689 3690 3691 Method* InstanceKlass::method_with_orig_idnum(int idnum) { 3692 if (idnum >= methods()->length()) { 3693 return NULL; 3694 } 3695 Method* m = methods()->at(idnum); 3696 if (m != NULL && m->orig_method_idnum() == idnum) { 3697 return m; 3698 } 3699 // Obsolete method idnum does not match the original idnum 3700 for (int index = 0; index < methods()->length(); ++index) { 3701 m = methods()->at(index); 3702 if (m->orig_method_idnum() == idnum) { 3703 return m; 3704 } 3705 } 3706 // None found, return null for the caller to handle. 3707 return NULL; 3708 } 3709 3710 3711 Method* InstanceKlass::method_with_orig_idnum(int idnum, int version) { 3712 InstanceKlass* holder = get_klass_version(version); 3713 if (holder == NULL) { 3714 return NULL; // The version of klass is gone, no method is found 3715 } 3716 Method* method = holder->method_with_orig_idnum(idnum); 3717 return method; 3718 } 3719 3720 #if INCLUDE_JVMTI 3721 JvmtiCachedClassFileData* InstanceKlass::get_cached_class_file() { 3722 if (MetaspaceShared::is_in_shared_space(_cached_class_file)) { 3723 // Ignore the archived class stream data 3724 return NULL; 3725 } else { 3726 return _cached_class_file; 3727 } 3728 } 3729 3730 jint InstanceKlass::get_cached_class_file_len() { 3731 return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file); 3732 } 3733 3734 unsigned char * InstanceKlass::get_cached_class_file_bytes() { 3735 return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file); 3736 } 3737 3738 #if INCLUDE_CDS 3739 JvmtiCachedClassFileData* InstanceKlass::get_archived_class_data() { 3740 if (DumpSharedSpaces) { 3741 return _cached_class_file; 3742 } else { 3743 assert(this->is_shared(), "class should be shared"); 3744 if (MetaspaceShared::is_in_shared_space(_cached_class_file)) { 3745 return _cached_class_file; 3746 } else { 3747 return NULL; 3748 } 3749 } 3750 } 3751 #endif 3752 #endif