1 /* 2 * Copyright (c) 1997, 2015, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25 #include "precompiled.hpp" 26 #include "classfile/javaClasses.hpp" 27 #include "classfile/systemDictionary.hpp" 28 #include "classfile/verifier.hpp" 29 #include "classfile/vmSymbols.hpp" 30 #include "compiler/compileBroker.hpp" 31 #include "gc/shared/collectedHeap.inline.hpp" 32 #include "gc/shared/specialized_oop_closures.hpp" 33 #include "interpreter/oopMapCache.hpp" 34 #include "interpreter/rewriter.hpp" 35 #include "jvmtifiles/jvmti.h" 36 #include "memory/heapInspection.hpp" 37 #include "memory/iterator.inline.hpp" 38 #include "memory/metadataFactory.hpp" 39 #include "memory/oopFactory.hpp" 40 #include "oops/fieldStreams.hpp" 41 #include "oops/instanceClassLoaderKlass.hpp" 42 #include "oops/instanceKlass.inline.hpp" 43 #include "oops/instanceMirrorKlass.hpp" 44 #include "oops/instanceOop.hpp" 45 #include "oops/klass.inline.hpp" 46 #include "oops/method.hpp" 47 #include "oops/oop.inline.hpp" 48 #include "oops/symbol.hpp" 49 #include "prims/jvmtiExport.hpp" 50 #include "prims/jvmtiRedefineClasses.hpp" 51 #include "prims/jvmtiRedefineClassesTrace.hpp" 52 #include "prims/jvmtiThreadState.hpp" 53 #include "prims/methodComparator.hpp" 54 #include "runtime/atomic.inline.hpp" 55 #include "runtime/fieldDescriptor.hpp" 56 #include "runtime/handles.inline.hpp" 57 #include "runtime/javaCalls.hpp" 58 #include "runtime/mutexLocker.hpp" 59 #include "runtime/orderAccess.inline.hpp" 60 #include "runtime/thread.inline.hpp" 61 #include "services/classLoadingService.hpp" 62 #include "services/threadService.hpp" 63 #include "utilities/dtrace.hpp" 64 #include "utilities/macros.hpp" 65 #ifdef COMPILER1 66 #include "c1/c1_Compiler.hpp" 67 #endif 68 69 #ifdef DTRACE_ENABLED 70 71 72 #define HOTSPOT_CLASS_INITIALIZATION_required HOTSPOT_CLASS_INITIALIZATION_REQUIRED 73 #define HOTSPOT_CLASS_INITIALIZATION_recursive HOTSPOT_CLASS_INITIALIZATION_RECURSIVE 74 #define HOTSPOT_CLASS_INITIALIZATION_concurrent HOTSPOT_CLASS_INITIALIZATION_CONCURRENT 75 #define HOTSPOT_CLASS_INITIALIZATION_erroneous HOTSPOT_CLASS_INITIALIZATION_ERRONEOUS 76 #define HOTSPOT_CLASS_INITIALIZATION_super__failed HOTSPOT_CLASS_INITIALIZATION_SUPER_FAILED 77 #define HOTSPOT_CLASS_INITIALIZATION_clinit HOTSPOT_CLASS_INITIALIZATION_CLINIT 78 #define HOTSPOT_CLASS_INITIALIZATION_error HOTSPOT_CLASS_INITIALIZATION_ERROR 79 #define HOTSPOT_CLASS_INITIALIZATION_end HOTSPOT_CLASS_INITIALIZATION_END 80 #define DTRACE_CLASSINIT_PROBE(type, clss, thread_type) \ 81 { \ 82 char* data = NULL; \ 83 int len = 0; \ 84 Symbol* name = (clss)->name(); \ 85 if (name != NULL) { \ 86 data = (char*)name->bytes(); \ 87 len = name->utf8_length(); \ 88 } \ 89 HOTSPOT_CLASS_INITIALIZATION_##type( \ 90 data, len, (clss)->class_loader(), thread_type); \ 91 } 92 93 #define DTRACE_CLASSINIT_PROBE_WAIT(type, clss, thread_type, wait) \ 94 { \ 95 char* data = NULL; \ 96 int len = 0; \ 97 Symbol* name = (clss)->name(); \ 98 if (name != NULL) { \ 99 data = (char*)name->bytes(); \ 100 len = name->utf8_length(); \ 101 } \ 102 HOTSPOT_CLASS_INITIALIZATION_##type( \ 103 data, len, (clss)->class_loader(), thread_type, wait); \ 104 } 105 106 #else // ndef DTRACE_ENABLED 107 108 #define DTRACE_CLASSINIT_PROBE(type, clss, thread_type) 109 #define DTRACE_CLASSINIT_PROBE_WAIT(type, clss, thread_type, wait) 110 111 #endif // ndef DTRACE_ENABLED 112 113 volatile int InstanceKlass::_total_instanceKlass_count = 0; 114 115 InstanceKlass* InstanceKlass::allocate_instance_klass( 116 ClassLoaderData* loader_data, 117 int vtable_len, 118 int itable_len, 119 int static_field_size, 120 int nonstatic_oop_map_size, 121 ReferenceType rt, 122 AccessFlags access_flags, 123 Symbol* name, 124 Klass* super_klass, 125 bool is_anonymous, 126 TRAPS) { 127 128 int size = InstanceKlass::size(vtable_len, itable_len, nonstatic_oop_map_size, 129 access_flags.is_interface(), is_anonymous); 130 131 // Allocation 132 InstanceKlass* ik; 133 if (rt == REF_NONE) { 134 if (name == vmSymbols::java_lang_Class()) { 135 ik = new (loader_data, size, THREAD) InstanceMirrorKlass( 136 vtable_len, itable_len, static_field_size, nonstatic_oop_map_size, rt, 137 access_flags, is_anonymous); 138 } else if (name == vmSymbols::java_lang_ClassLoader() || 139 (SystemDictionary::ClassLoader_klass_loaded() && 140 super_klass != NULL && 141 super_klass->is_subtype_of(SystemDictionary::ClassLoader_klass()))) { 142 ik = new (loader_data, size, THREAD) InstanceClassLoaderKlass( 143 vtable_len, itable_len, static_field_size, nonstatic_oop_map_size, rt, 144 access_flags, is_anonymous); 145 } else { 146 // normal class 147 ik = new (loader_data, size, THREAD) InstanceKlass( 148 vtable_len, itable_len, static_field_size, nonstatic_oop_map_size, 149 InstanceKlass::_misc_kind_other, rt, access_flags, is_anonymous); 150 } 151 } else { 152 // reference klass 153 ik = new (loader_data, size, THREAD) InstanceRefKlass( 154 vtable_len, itable_len, static_field_size, nonstatic_oop_map_size, rt, 155 access_flags, is_anonymous); 156 } 157 158 // Check for pending exception before adding to the loader data and incrementing 159 // class count. Can get OOM here. 160 if (HAS_PENDING_EXCEPTION) { 161 return NULL; 162 } 163 164 // Add all classes to our internal class loader list here, 165 // including classes in the bootstrap (NULL) class loader. 166 loader_data->add_class(ik); 167 168 Atomic::inc(&_total_instanceKlass_count); 169 return ik; 170 } 171 172 173 // copy method ordering from resource area to Metaspace 174 void InstanceKlass::copy_method_ordering(intArray* m, TRAPS) { 175 if (m != NULL) { 176 // allocate a new array and copy contents (memcpy?) 177 _method_ordering = MetadataFactory::new_array<int>(class_loader_data(), m->length(), CHECK); 178 for (int i = 0; i < m->length(); i++) { 179 _method_ordering->at_put(i, m->at(i)); 180 } 181 } else { 182 _method_ordering = Universe::the_empty_int_array(); 183 } 184 } 185 186 // create a new array of vtable_indices for default methods 187 Array<int>* InstanceKlass::create_new_default_vtable_indices(int len, TRAPS) { 188 Array<int>* vtable_indices = MetadataFactory::new_array<int>(class_loader_data(), len, CHECK_NULL); 189 assert(default_vtable_indices() == NULL, "only create once"); 190 set_default_vtable_indices(vtable_indices); 191 return vtable_indices; 192 } 193 194 InstanceKlass::InstanceKlass(int vtable_len, 195 int itable_len, 196 int static_field_size, 197 int nonstatic_oop_map_size, 198 unsigned kind, 199 ReferenceType rt, 200 AccessFlags access_flags, 201 bool is_anonymous) { 202 No_Safepoint_Verifier no_safepoint; // until k becomes parsable 203 204 int iksize = InstanceKlass::size(vtable_len, itable_len, nonstatic_oop_map_size, 205 access_flags.is_interface(), is_anonymous); 206 207 set_vtable_length(vtable_len); 208 set_itable_length(itable_len); 209 set_static_field_size(static_field_size); 210 set_nonstatic_oop_map_size(nonstatic_oop_map_size); 211 set_access_flags(access_flags); 212 _misc_flags = 0; // initialize to zero 213 set_kind(kind); 214 set_is_anonymous(is_anonymous); 215 assert(size() == iksize, "wrong size for object"); 216 217 set_array_klasses(NULL); 218 set_methods(NULL); 219 set_method_ordering(NULL); 220 set_default_methods(NULL); 221 set_default_vtable_indices(NULL); 222 set_local_interfaces(NULL); 223 set_transitive_interfaces(NULL); 224 init_implementor(); 225 set_fields(NULL, 0); 226 set_constants(NULL); 227 set_class_loader_data(NULL); 228 set_source_file_name_index(0); 229 set_source_debug_extension(NULL, 0); 230 set_array_name(NULL); 231 set_inner_classes(NULL); 232 set_static_oop_field_count(0); 233 set_nonstatic_field_size(0); 234 set_is_marked_dependent(false); 235 set_has_unloaded_dependent(false); 236 set_init_state(InstanceKlass::allocated); 237 set_init_thread(NULL); 238 set_reference_type(rt); 239 set_oop_map_cache(NULL); 240 set_jni_ids(NULL); 241 set_osr_nmethods_head(NULL); 242 set_breakpoints(NULL); 243 init_previous_versions(); 244 set_generic_signature_index(0); 245 release_set_methods_jmethod_ids(NULL); 246 set_annotations(NULL); 247 set_jvmti_cached_class_field_map(NULL); 248 set_initial_method_idnum(0); 249 _dependencies = NULL; 250 set_jvmti_cached_class_field_map(NULL); 251 set_cached_class_file(NULL); 252 set_initial_method_idnum(0); 253 set_minor_version(0); 254 set_major_version(0); 255 NOT_PRODUCT(_verify_count = 0;) 256 257 // initialize the non-header words to zero 258 intptr_t* p = (intptr_t*)this; 259 for (int index = InstanceKlass::header_size(); index < iksize; index++) { 260 p[index] = NULL_WORD; 261 } 262 263 // Set temporary value until parseClassFile updates it with the real instance 264 // size. 265 set_layout_helper(Klass::instance_layout_helper(0, true)); 266 } 267 268 269 void InstanceKlass::deallocate_methods(ClassLoaderData* loader_data, 270 Array<Method*>* methods) { 271 if (methods != NULL && methods != Universe::the_empty_method_array() && 272 !methods->is_shared()) { 273 for (int i = 0; i < methods->length(); i++) { 274 Method* method = methods->at(i); 275 if (method == NULL) continue; // maybe null if error processing 276 // Only want to delete methods that are not executing for RedefineClasses. 277 // The previous version will point to them so they're not totally dangling 278 assert (!method->on_stack(), "shouldn't be called with methods on stack"); 279 MetadataFactory::free_metadata(loader_data, method); 280 } 281 MetadataFactory::free_array<Method*>(loader_data, methods); 282 } 283 } 284 285 void InstanceKlass::deallocate_interfaces(ClassLoaderData* loader_data, 286 Klass* super_klass, 287 Array<Klass*>* local_interfaces, 288 Array<Klass*>* transitive_interfaces) { 289 // Only deallocate transitive interfaces if not empty, same as super class 290 // or same as local interfaces. See code in parseClassFile. 291 Array<Klass*>* ti = transitive_interfaces; 292 if (ti != Universe::the_empty_klass_array() && ti != local_interfaces) { 293 // check that the interfaces don't come from super class 294 Array<Klass*>* sti = (super_klass == NULL) ? NULL : 295 InstanceKlass::cast(super_klass)->transitive_interfaces(); 296 if (ti != sti && ti != NULL && !ti->is_shared()) { 297 MetadataFactory::free_array<Klass*>(loader_data, ti); 298 } 299 } 300 301 // local interfaces can be empty 302 if (local_interfaces != Universe::the_empty_klass_array() && 303 local_interfaces != NULL && !local_interfaces->is_shared()) { 304 MetadataFactory::free_array<Klass*>(loader_data, local_interfaces); 305 } 306 } 307 308 // This function deallocates the metadata and C heap pointers that the 309 // InstanceKlass points to. 310 void InstanceKlass::deallocate_contents(ClassLoaderData* loader_data) { 311 312 // Orphan the mirror first, CMS thinks it's still live. 313 if (java_mirror() != NULL) { 314 java_lang_Class::set_klass(java_mirror(), NULL); 315 } 316 317 // Need to take this class off the class loader data list. 318 loader_data->remove_class(this); 319 320 // The array_klass for this class is created later, after error handling. 321 // For class redefinition, we keep the original class so this scratch class 322 // doesn't have an array class. Either way, assert that there is nothing 323 // to deallocate. 324 assert(array_klasses() == NULL, "array classes shouldn't be created for this class yet"); 325 326 // Release C heap allocated data that this might point to, which includes 327 // reference counting symbol names. 328 release_C_heap_structures(); 329 330 deallocate_methods(loader_data, methods()); 331 set_methods(NULL); 332 333 if (method_ordering() != NULL && 334 method_ordering() != Universe::the_empty_int_array() && 335 !method_ordering()->is_shared()) { 336 MetadataFactory::free_array<int>(loader_data, method_ordering()); 337 } 338 set_method_ordering(NULL); 339 340 // default methods can be empty 341 if (default_methods() != NULL && 342 default_methods() != Universe::the_empty_method_array() && 343 !default_methods()->is_shared()) { 344 MetadataFactory::free_array<Method*>(loader_data, default_methods()); 345 } 346 // Do NOT deallocate the default methods, they are owned by superinterfaces. 347 set_default_methods(NULL); 348 349 // default methods vtable indices can be empty 350 if (default_vtable_indices() != NULL && 351 !default_vtable_indices()->is_shared()) { 352 MetadataFactory::free_array<int>(loader_data, default_vtable_indices()); 353 } 354 set_default_vtable_indices(NULL); 355 356 357 // This array is in Klass, but remove it with the InstanceKlass since 358 // this place would be the only caller and it can share memory with transitive 359 // interfaces. 360 if (secondary_supers() != NULL && 361 secondary_supers() != Universe::the_empty_klass_array() && 362 secondary_supers() != transitive_interfaces() && 363 !secondary_supers()->is_shared()) { 364 MetadataFactory::free_array<Klass*>(loader_data, secondary_supers()); 365 } 366 set_secondary_supers(NULL); 367 368 deallocate_interfaces(loader_data, super(), local_interfaces(), transitive_interfaces()); 369 set_transitive_interfaces(NULL); 370 set_local_interfaces(NULL); 371 372 if (fields() != NULL && !fields()->is_shared()) { 373 MetadataFactory::free_array<jushort>(loader_data, fields()); 374 } 375 set_fields(NULL, 0); 376 377 // If a method from a redefined class is using this constant pool, don't 378 // delete it, yet. The new class's previous version will point to this. 379 if (constants() != NULL) { 380 assert (!constants()->on_stack(), "shouldn't be called if anything is onstack"); 381 if (!constants()->is_shared()) { 382 MetadataFactory::free_metadata(loader_data, constants()); 383 } 384 // Delete any cached resolution errors for the constant pool 385 SystemDictionary::delete_resolution_error(constants()); 386 387 set_constants(NULL); 388 } 389 390 if (inner_classes() != NULL && 391 inner_classes() != Universe::the_empty_short_array() && 392 !inner_classes()->is_shared()) { 393 MetadataFactory::free_array<jushort>(loader_data, inner_classes()); 394 } 395 set_inner_classes(NULL); 396 397 // We should deallocate the Annotations instance if it's not in shared spaces. 398 if (annotations() != NULL && !annotations()->is_shared()) { 399 MetadataFactory::free_metadata(loader_data, annotations()); 400 } 401 set_annotations(NULL); 402 } 403 404 bool InstanceKlass::should_be_initialized() const { 405 return !is_initialized(); 406 } 407 408 klassVtable* InstanceKlass::vtable() const { 409 return new klassVtable(this, start_of_vtable(), vtable_length() / vtableEntry::size()); 410 } 411 412 klassItable* InstanceKlass::itable() const { 413 return new klassItable(instanceKlassHandle(this)); 414 } 415 416 void InstanceKlass::eager_initialize(Thread *thread) { 417 if (!EagerInitialization) return; 418 419 if (this->is_not_initialized()) { 420 // abort if the the class has a class initializer 421 if (this->class_initializer() != NULL) return; 422 423 // abort if it is java.lang.Object (initialization is handled in genesis) 424 Klass* super = this->super(); 425 if (super == NULL) return; 426 427 // abort if the super class should be initialized 428 if (!InstanceKlass::cast(super)->is_initialized()) return; 429 430 // call body to expose the this pointer 431 instanceKlassHandle this_k(thread, this); 432 eager_initialize_impl(this_k); 433 } 434 } 435 436 // JVMTI spec thinks there are signers and protection domain in the 437 // instanceKlass. These accessors pretend these fields are there. 438 // The hprof specification also thinks these fields are in InstanceKlass. 439 oop InstanceKlass::protection_domain() const { 440 // return the protection_domain from the mirror 441 return java_lang_Class::protection_domain(java_mirror()); 442 } 443 444 // To remove these from requires an incompatible change and CCC request. 445 objArrayOop InstanceKlass::signers() const { 446 // return the signers from the mirror 447 return java_lang_Class::signers(java_mirror()); 448 } 449 450 oop InstanceKlass::init_lock() const { 451 // return the init lock from the mirror 452 oop lock = java_lang_Class::init_lock(java_mirror()); 453 // Prevent reordering with any access of initialization state 454 OrderAccess::loadload(); 455 assert((oop)lock != NULL || !is_not_initialized(), // initialized or in_error state 456 "only fully initialized state can have a null lock"); 457 return lock; 458 } 459 460 // Set the initialization lock to null so the object can be GC'ed. Any racing 461 // threads to get this lock will see a null lock and will not lock. 462 // That's okay because they all check for initialized state after getting 463 // the lock and return. 464 void InstanceKlass::fence_and_clear_init_lock() { 465 // make sure previous stores are all done, notably the init_state. 466 OrderAccess::storestore(); 467 java_lang_Class::set_init_lock(java_mirror(), NULL); 468 assert(!is_not_initialized(), "class must be initialized now"); 469 } 470 471 void InstanceKlass::eager_initialize_impl(instanceKlassHandle this_k) { 472 EXCEPTION_MARK; 473 oop init_lock = this_k->init_lock(); 474 ObjectLocker ol(init_lock, THREAD, init_lock != NULL); 475 476 // abort if someone beat us to the initialization 477 if (!this_k->is_not_initialized()) return; // note: not equivalent to is_initialized() 478 479 ClassState old_state = this_k->init_state(); 480 link_class_impl(this_k, true, THREAD); 481 if (HAS_PENDING_EXCEPTION) { 482 CLEAR_PENDING_EXCEPTION; 483 // Abort if linking the class throws an exception. 484 485 // Use a test to avoid redundantly resetting the state if there's 486 // no change. Set_init_state() asserts that state changes make 487 // progress, whereas here we might just be spinning in place. 488 if( old_state != this_k->_init_state ) 489 this_k->set_init_state (old_state); 490 } else { 491 // linking successfull, mark class as initialized 492 this_k->set_init_state (fully_initialized); 493 this_k->fence_and_clear_init_lock(); 494 // trace 495 if (TraceClassInitialization) { 496 ResourceMark rm(THREAD); 497 tty->print_cr("[Initialized %s without side effects]", this_k->external_name()); 498 } 499 } 500 } 501 502 503 // See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization 504 // process. The step comments refers to the procedure described in that section. 505 // Note: implementation moved to static method to expose the this pointer. 506 void InstanceKlass::initialize(TRAPS) { 507 if (this->should_be_initialized()) { 508 HandleMark hm(THREAD); 509 instanceKlassHandle this_k(THREAD, this); 510 initialize_impl(this_k, CHECK); 511 // Note: at this point the class may be initialized 512 // OR it may be in the state of being initialized 513 // in case of recursive initialization! 514 } else { 515 assert(is_initialized(), "sanity check"); 516 } 517 } 518 519 520 bool InstanceKlass::verify_code( 521 instanceKlassHandle this_k, bool throw_verifyerror, TRAPS) { 522 // 1) Verify the bytecodes 523 Verifier::Mode mode = 524 throw_verifyerror ? Verifier::ThrowException : Verifier::NoException; 525 return Verifier::verify(this_k, mode, this_k->should_verify_class(), THREAD); 526 } 527 528 529 // Used exclusively by the shared spaces dump mechanism to prevent 530 // classes mapped into the shared regions in new VMs from appearing linked. 531 532 void InstanceKlass::unlink_class() { 533 assert(is_linked(), "must be linked"); 534 _init_state = loaded; 535 } 536 537 void InstanceKlass::link_class(TRAPS) { 538 assert(is_loaded(), "must be loaded"); 539 if (!is_linked()) { 540 HandleMark hm(THREAD); 541 instanceKlassHandle this_k(THREAD, this); 542 link_class_impl(this_k, true, CHECK); 543 } 544 } 545 546 // Called to verify that a class can link during initialization, without 547 // throwing a VerifyError. 548 bool InstanceKlass::link_class_or_fail(TRAPS) { 549 assert(is_loaded(), "must be loaded"); 550 if (!is_linked()) { 551 HandleMark hm(THREAD); 552 instanceKlassHandle this_k(THREAD, this); 553 link_class_impl(this_k, false, CHECK_false); 554 } 555 return is_linked(); 556 } 557 558 bool InstanceKlass::link_class_impl( 559 instanceKlassHandle this_k, bool throw_verifyerror, TRAPS) { 560 // check for error state 561 if (this_k->is_in_error_state()) { 562 ResourceMark rm(THREAD); 563 THROW_MSG_(vmSymbols::java_lang_NoClassDefFoundError(), 564 this_k->external_name(), false); 565 } 566 // return if already verified 567 if (this_k->is_linked()) { 568 return true; 569 } 570 571 // Timing 572 // timer handles recursion 573 assert(THREAD->is_Java_thread(), "non-JavaThread in link_class_impl"); 574 JavaThread* jt = (JavaThread*)THREAD; 575 576 // link super class before linking this class 577 instanceKlassHandle super(THREAD, this_k->super()); 578 if (super.not_null()) { 579 if (super->is_interface()) { // check if super class is an interface 580 ResourceMark rm(THREAD); 581 Exceptions::fthrow( 582 THREAD_AND_LOCATION, 583 vmSymbols::java_lang_IncompatibleClassChangeError(), 584 "class %s has interface %s as super class", 585 this_k->external_name(), 586 super->external_name() 587 ); 588 return false; 589 } 590 591 link_class_impl(super, throw_verifyerror, CHECK_false); 592 } 593 594 // link all interfaces implemented by this class before linking this class 595 Array<Klass*>* interfaces = this_k->local_interfaces(); 596 int num_interfaces = interfaces->length(); 597 for (int index = 0; index < num_interfaces; index++) { 598 HandleMark hm(THREAD); 599 instanceKlassHandle ih(THREAD, interfaces->at(index)); 600 link_class_impl(ih, throw_verifyerror, CHECK_false); 601 } 602 603 // in case the class is linked in the process of linking its superclasses 604 if (this_k->is_linked()) { 605 return true; 606 } 607 608 // trace only the link time for this klass that includes 609 // the verification time 610 PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(), 611 ClassLoader::perf_class_link_selftime(), 612 ClassLoader::perf_classes_linked(), 613 jt->get_thread_stat()->perf_recursion_counts_addr(), 614 jt->get_thread_stat()->perf_timers_addr(), 615 PerfClassTraceTime::CLASS_LINK); 616 617 // verification & rewriting 618 { 619 oop init_lock = this_k->init_lock(); 620 ObjectLocker ol(init_lock, THREAD, init_lock != NULL); 621 // rewritten will have been set if loader constraint error found 622 // on an earlier link attempt 623 // don't verify or rewrite if already rewritten 624 625 if (!this_k->is_linked()) { 626 if (!this_k->is_rewritten()) { 627 { 628 bool verify_ok = verify_code(this_k, throw_verifyerror, THREAD); 629 if (!verify_ok) { 630 return false; 631 } 632 } 633 634 // Just in case a side-effect of verify linked this class already 635 // (which can sometimes happen since the verifier loads classes 636 // using custom class loaders, which are free to initialize things) 637 if (this_k->is_linked()) { 638 return true; 639 } 640 641 // also sets rewritten 642 this_k->rewrite_class(CHECK_false); 643 } 644 645 // relocate jsrs and link methods after they are all rewritten 646 this_k->link_methods(CHECK_false); 647 648 // Initialize the vtable and interface table after 649 // methods have been rewritten since rewrite may 650 // fabricate new Method*s. 651 // also does loader constraint checking 652 if (!this_k()->is_shared()) { 653 ResourceMark rm(THREAD); 654 this_k->vtable()->initialize_vtable(true, CHECK_false); 655 this_k->itable()->initialize_itable(true, CHECK_false); 656 } 657 #ifdef ASSERT 658 else { 659 ResourceMark rm(THREAD); 660 this_k->vtable()->verify(tty, true); 661 // In case itable verification is ever added. 662 // this_k->itable()->verify(tty, true); 663 } 664 #endif 665 this_k->set_init_state(linked); 666 if (JvmtiExport::should_post_class_prepare()) { 667 Thread *thread = THREAD; 668 assert(thread->is_Java_thread(), "thread->is_Java_thread()"); 669 JvmtiExport::post_class_prepare((JavaThread *) thread, this_k()); 670 } 671 } 672 } 673 return true; 674 } 675 676 677 // Rewrite the byte codes of all of the methods of a class. 678 // The rewriter must be called exactly once. Rewriting must happen after 679 // verification but before the first method of the class is executed. 680 void InstanceKlass::rewrite_class(TRAPS) { 681 assert(is_loaded(), "must be loaded"); 682 instanceKlassHandle this_k(THREAD, this); 683 if (this_k->is_rewritten()) { 684 assert(this_k()->is_shared(), "rewriting an unshared class?"); 685 return; 686 } 687 Rewriter::rewrite(this_k, CHECK); 688 this_k->set_rewritten(); 689 } 690 691 // Now relocate and link method entry points after class is rewritten. 692 // This is outside is_rewritten flag. In case of an exception, it can be 693 // executed more than once. 694 void InstanceKlass::link_methods(TRAPS) { 695 int len = methods()->length(); 696 for (int i = len-1; i >= 0; i--) { 697 methodHandle m(THREAD, methods()->at(i)); 698 699 // Set up method entry points for compiler and interpreter . 700 m->link_method(m, CHECK); 701 } 702 } 703 704 // Eagerly initialize superinterfaces that declare default methods (concrete instance: any access) 705 void InstanceKlass::initialize_super_interfaces(instanceKlassHandle this_k, TRAPS) { 706 if (this_k->has_default_methods()) { 707 for (int i = 0; i < this_k->local_interfaces()->length(); ++i) { 708 Klass* iface = this_k->local_interfaces()->at(i); 709 InstanceKlass* ik = InstanceKlass::cast(iface); 710 if (ik->should_be_initialized()) { 711 if (ik->has_default_methods()) { 712 ik->initialize_super_interfaces(ik, THREAD); 713 } 714 // Only initialize() interfaces that "declare" concrete methods. 715 // has_default_methods drives searching superinterfaces since it 716 // means has_default_methods in its superinterface hierarchy 717 if (!HAS_PENDING_EXCEPTION && ik->declares_default_methods()) { 718 ik->initialize(THREAD); 719 } 720 if (HAS_PENDING_EXCEPTION) { 721 Handle e(THREAD, PENDING_EXCEPTION); 722 CLEAR_PENDING_EXCEPTION; 723 { 724 EXCEPTION_MARK; 725 // Locks object, set state, and notify all waiting threads 726 this_k->set_initialization_state_and_notify( 727 initialization_error, THREAD); 728 729 // ignore any exception thrown, superclass initialization error is 730 // thrown below 731 CLEAR_PENDING_EXCEPTION; 732 } 733 THROW_OOP(e()); 734 } 735 } 736 } 737 } 738 } 739 740 void InstanceKlass::initialize_impl(instanceKlassHandle this_k, TRAPS) { 741 // Make sure klass is linked (verified) before initialization 742 // A class could already be verified, since it has been reflected upon. 743 this_k->link_class(CHECK); 744 745 DTRACE_CLASSINIT_PROBE(required, InstanceKlass::cast(this_k()), -1); 746 747 bool wait = false; 748 749 // refer to the JVM book page 47 for description of steps 750 // Step 1 751 { 752 oop init_lock = this_k->init_lock(); 753 ObjectLocker ol(init_lock, THREAD, init_lock != NULL); 754 755 Thread *self = THREAD; // it's passed the current thread 756 757 // Step 2 758 // If we were to use wait() instead of waitInterruptibly() then 759 // we might end up throwing IE from link/symbol resolution sites 760 // that aren't expected to throw. This would wreak havoc. See 6320309. 761 while(this_k->is_being_initialized() && !this_k->is_reentrant_initialization(self)) { 762 wait = true; 763 ol.waitUninterruptibly(CHECK); 764 } 765 766 // Step 3 767 if (this_k->is_being_initialized() && this_k->is_reentrant_initialization(self)) { 768 DTRACE_CLASSINIT_PROBE_WAIT(recursive, InstanceKlass::cast(this_k()), -1,wait); 769 return; 770 } 771 772 // Step 4 773 if (this_k->is_initialized()) { 774 DTRACE_CLASSINIT_PROBE_WAIT(concurrent, InstanceKlass::cast(this_k()), -1,wait); 775 return; 776 } 777 778 // Step 5 779 if (this_k->is_in_error_state()) { 780 DTRACE_CLASSINIT_PROBE_WAIT(erroneous, InstanceKlass::cast(this_k()), -1,wait); 781 ResourceMark rm(THREAD); 782 const char* desc = "Could not initialize class "; 783 const char* className = this_k->external_name(); 784 size_t msglen = strlen(desc) + strlen(className) + 1; 785 char* message = NEW_RESOURCE_ARRAY(char, msglen); 786 if (NULL == message) { 787 // Out of memory: can't create detailed error message 788 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), className); 789 } else { 790 jio_snprintf(message, msglen, "%s%s", desc, className); 791 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), message); 792 } 793 } 794 795 // Step 6 796 this_k->set_init_state(being_initialized); 797 this_k->set_init_thread(self); 798 } 799 800 // Step 7 801 Klass* super_klass = this_k->super(); 802 if (super_klass != NULL && !this_k->is_interface() && super_klass->should_be_initialized()) { 803 super_klass->initialize(THREAD); 804 805 if (HAS_PENDING_EXCEPTION) { 806 Handle e(THREAD, PENDING_EXCEPTION); 807 CLEAR_PENDING_EXCEPTION; 808 { 809 EXCEPTION_MARK; 810 this_k->set_initialization_state_and_notify(initialization_error, THREAD); // Locks object, set state, and notify all waiting threads 811 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, superclass initialization error is thrown below 812 } 813 DTRACE_CLASSINIT_PROBE_WAIT(super__failed, InstanceKlass::cast(this_k()), -1,wait); 814 THROW_OOP(e()); 815 } 816 } 817 818 // Recursively initialize any superinterfaces that declare default methods 819 // Only need to recurse if has_default_methods which includes declaring and 820 // inheriting default methods 821 if (this_k->has_default_methods()) { 822 this_k->initialize_super_interfaces(this_k, CHECK); 823 } 824 825 // Step 8 826 { 827 assert(THREAD->is_Java_thread(), "non-JavaThread in initialize_impl"); 828 JavaThread* jt = (JavaThread*)THREAD; 829 DTRACE_CLASSINIT_PROBE_WAIT(clinit, InstanceKlass::cast(this_k()), -1,wait); 830 // Timer includes any side effects of class initialization (resolution, 831 // etc), but not recursive entry into call_class_initializer(). 832 PerfClassTraceTime timer(ClassLoader::perf_class_init_time(), 833 ClassLoader::perf_class_init_selftime(), 834 ClassLoader::perf_classes_inited(), 835 jt->get_thread_stat()->perf_recursion_counts_addr(), 836 jt->get_thread_stat()->perf_timers_addr(), 837 PerfClassTraceTime::CLASS_CLINIT); 838 this_k->call_class_initializer(THREAD); 839 } 840 841 // Step 9 842 if (!HAS_PENDING_EXCEPTION) { 843 this_k->set_initialization_state_and_notify(fully_initialized, CHECK); 844 { ResourceMark rm(THREAD); 845 debug_only(this_k->vtable()->verify(tty, true);) 846 } 847 } 848 else { 849 // Step 10 and 11 850 Handle e(THREAD, PENDING_EXCEPTION); 851 CLEAR_PENDING_EXCEPTION; 852 // JVMTI has already reported the pending exception 853 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError 854 JvmtiExport::clear_detected_exception((JavaThread*)THREAD); 855 { 856 EXCEPTION_MARK; 857 this_k->set_initialization_state_and_notify(initialization_error, THREAD); 858 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, class initialization error is thrown below 859 // JVMTI has already reported the pending exception 860 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError 861 JvmtiExport::clear_detected_exception((JavaThread*)THREAD); 862 } 863 DTRACE_CLASSINIT_PROBE_WAIT(error, InstanceKlass::cast(this_k()), -1,wait); 864 if (e->is_a(SystemDictionary::Error_klass())) { 865 THROW_OOP(e()); 866 } else { 867 JavaCallArguments args(e); 868 THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(), 869 vmSymbols::throwable_void_signature(), 870 &args); 871 } 872 } 873 DTRACE_CLASSINIT_PROBE_WAIT(end, InstanceKlass::cast(this_k()), -1,wait); 874 } 875 876 877 // Note: implementation moved to static method to expose the this pointer. 878 void InstanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) { 879 instanceKlassHandle kh(THREAD, this); 880 set_initialization_state_and_notify_impl(kh, state, CHECK); 881 } 882 883 void InstanceKlass::set_initialization_state_and_notify_impl(instanceKlassHandle this_k, ClassState state, TRAPS) { 884 oop init_lock = this_k->init_lock(); 885 ObjectLocker ol(init_lock, THREAD, init_lock != NULL); 886 this_k->set_init_state(state); 887 this_k->fence_and_clear_init_lock(); 888 ol.notify_all(CHECK); 889 } 890 891 // The embedded _implementor field can only record one implementor. 892 // When there are more than one implementors, the _implementor field 893 // is set to the interface Klass* itself. Following are the possible 894 // values for the _implementor field: 895 // NULL - no implementor 896 // implementor Klass* - one implementor 897 // self - more than one implementor 898 // 899 // The _implementor field only exists for interfaces. 900 void InstanceKlass::add_implementor(Klass* k) { 901 assert(Compile_lock->owned_by_self(), ""); 902 assert(is_interface(), "not interface"); 903 // Filter out my subinterfaces. 904 // (Note: Interfaces are never on the subklass list.) 905 if (InstanceKlass::cast(k)->is_interface()) return; 906 907 // Filter out subclasses whose supers already implement me. 908 // (Note: CHA must walk subclasses of direct implementors 909 // in order to locate indirect implementors.) 910 Klass* sk = InstanceKlass::cast(k)->super(); 911 if (sk != NULL && InstanceKlass::cast(sk)->implements_interface(this)) 912 // We only need to check one immediate superclass, since the 913 // implements_interface query looks at transitive_interfaces. 914 // Any supers of the super have the same (or fewer) transitive_interfaces. 915 return; 916 917 Klass* ik = implementor(); 918 if (ik == NULL) { 919 set_implementor(k); 920 } else if (ik != this) { 921 // There is already an implementor. Use itself as an indicator of 922 // more than one implementors. 923 set_implementor(this); 924 } 925 926 // The implementor also implements the transitive_interfaces 927 for (int index = 0; index < local_interfaces()->length(); index++) { 928 InstanceKlass::cast(local_interfaces()->at(index))->add_implementor(k); 929 } 930 } 931 932 void InstanceKlass::init_implementor() { 933 if (is_interface()) { 934 set_implementor(NULL); 935 } 936 } 937 938 939 void InstanceKlass::process_interfaces(Thread *thread) { 940 // link this class into the implementors list of every interface it implements 941 for (int i = local_interfaces()->length() - 1; i >= 0; i--) { 942 assert(local_interfaces()->at(i)->is_klass(), "must be a klass"); 943 InstanceKlass* interf = InstanceKlass::cast(local_interfaces()->at(i)); 944 assert(interf->is_interface(), "expected interface"); 945 interf->add_implementor(this); 946 } 947 } 948 949 bool InstanceKlass::can_be_primary_super_slow() const { 950 if (is_interface()) 951 return false; 952 else 953 return Klass::can_be_primary_super_slow(); 954 } 955 956 GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots) { 957 // The secondaries are the implemented interfaces. 958 InstanceKlass* ik = InstanceKlass::cast(this); 959 Array<Klass*>* interfaces = ik->transitive_interfaces(); 960 int num_secondaries = num_extra_slots + interfaces->length(); 961 if (num_secondaries == 0) { 962 // Must share this for correct bootstrapping! 963 set_secondary_supers(Universe::the_empty_klass_array()); 964 return NULL; 965 } else if (num_extra_slots == 0) { 966 // The secondary super list is exactly the same as the transitive interfaces. 967 // Redefine classes has to be careful not to delete this! 968 set_secondary_supers(interfaces); 969 return NULL; 970 } else { 971 // Copy transitive interfaces to a temporary growable array to be constructed 972 // into the secondary super list with extra slots. 973 GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length()); 974 for (int i = 0; i < interfaces->length(); i++) { 975 secondaries->push(interfaces->at(i)); 976 } 977 return secondaries; 978 } 979 } 980 981 bool InstanceKlass::compute_is_subtype_of(Klass* k) { 982 if (k->is_interface()) { 983 return implements_interface(k); 984 } else { 985 return Klass::compute_is_subtype_of(k); 986 } 987 } 988 989 bool InstanceKlass::implements_interface(Klass* k) const { 990 if (this == k) return true; 991 assert(k->is_interface(), "should be an interface class"); 992 for (int i = 0; i < transitive_interfaces()->length(); i++) { 993 if (transitive_interfaces()->at(i) == k) { 994 return true; 995 } 996 } 997 return false; 998 } 999 1000 bool InstanceKlass::is_same_or_direct_interface(Klass *k) const { 1001 // Verify direct super interface 1002 if (this == k) return true; 1003 assert(k->is_interface(), "should be an interface class"); 1004 for (int i = 0; i < local_interfaces()->length(); i++) { 1005 if (local_interfaces()->at(i) == k) { 1006 return true; 1007 } 1008 } 1009 return false; 1010 } 1011 1012 objArrayOop InstanceKlass::allocate_objArray(int n, int length, TRAPS) { 1013 if (length < 0) THROW_0(vmSymbols::java_lang_NegativeArraySizeException()); 1014 if (length > arrayOopDesc::max_array_length(T_OBJECT)) { 1015 report_java_out_of_memory("Requested array size exceeds VM limit"); 1016 JvmtiExport::post_array_size_exhausted(); 1017 THROW_OOP_0(Universe::out_of_memory_error_array_size()); 1018 } 1019 int size = objArrayOopDesc::object_size(length); 1020 Klass* ak = array_klass(n, CHECK_NULL); 1021 KlassHandle h_ak (THREAD, ak); 1022 objArrayOop o = 1023 (objArrayOop)CollectedHeap::array_allocate(h_ak, size, length, CHECK_NULL); 1024 return o; 1025 } 1026 1027 instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) { 1028 if (TraceFinalizerRegistration) { 1029 tty->print("Registered "); 1030 i->print_value_on(tty); 1031 tty->print_cr(" (" INTPTR_FORMAT ") as finalizable", p2i(i)); 1032 } 1033 instanceHandle h_i(THREAD, i); 1034 // Pass the handle as argument, JavaCalls::call expects oop as jobjects 1035 JavaValue result(T_VOID); 1036 JavaCallArguments args(h_i); 1037 methodHandle mh (THREAD, Universe::finalizer_register_method()); 1038 JavaCalls::call(&result, mh, &args, CHECK_NULL); 1039 return h_i(); 1040 } 1041 1042 instanceOop InstanceKlass::allocate_instance(TRAPS) { 1043 bool has_finalizer_flag = has_finalizer(); // Query before possible GC 1044 int size = size_helper(); // Query before forming handle. 1045 1046 KlassHandle h_k(THREAD, this); 1047 1048 instanceOop i; 1049 1050 i = (instanceOop)CollectedHeap::obj_allocate(h_k, size, CHECK_NULL); 1051 if (has_finalizer_flag && !RegisterFinalizersAtInit) { 1052 i = register_finalizer(i, CHECK_NULL); 1053 } 1054 return i; 1055 } 1056 1057 void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) { 1058 if (is_interface() || is_abstract()) { 1059 ResourceMark rm(THREAD); 1060 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError() 1061 : vmSymbols::java_lang_InstantiationException(), external_name()); 1062 } 1063 if (this == SystemDictionary::Class_klass()) { 1064 ResourceMark rm(THREAD); 1065 THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError() 1066 : vmSymbols::java_lang_IllegalAccessException(), external_name()); 1067 } 1068 } 1069 1070 Klass* InstanceKlass::array_klass_impl(bool or_null, int n, TRAPS) { 1071 instanceKlassHandle this_k(THREAD, this); 1072 return array_klass_impl(this_k, or_null, n, THREAD); 1073 } 1074 1075 Klass* InstanceKlass::array_klass_impl(instanceKlassHandle this_k, bool or_null, int n, TRAPS) { 1076 if (this_k->array_klasses() == NULL) { 1077 if (or_null) return NULL; 1078 1079 ResourceMark rm; 1080 JavaThread *jt = (JavaThread *)THREAD; 1081 { 1082 // Atomic creation of array_klasses 1083 MutexLocker mc(Compile_lock, THREAD); // for vtables 1084 MutexLocker ma(MultiArray_lock, THREAD); 1085 1086 // Check if update has already taken place 1087 if (this_k->array_klasses() == NULL) { 1088 Klass* k = ObjArrayKlass::allocate_objArray_klass(this_k->class_loader_data(), 1, this_k, CHECK_NULL); 1089 this_k->set_array_klasses(k); 1090 } 1091 } 1092 } 1093 // _this will always be set at this point 1094 ObjArrayKlass* oak = (ObjArrayKlass*)this_k->array_klasses(); 1095 if (or_null) { 1096 return oak->array_klass_or_null(n); 1097 } 1098 return oak->array_klass(n, THREAD); 1099 } 1100 1101 Klass* InstanceKlass::array_klass_impl(bool or_null, TRAPS) { 1102 return array_klass_impl(or_null, 1, THREAD); 1103 } 1104 1105 void InstanceKlass::call_class_initializer(TRAPS) { 1106 instanceKlassHandle ik (THREAD, this); 1107 call_class_initializer_impl(ik, THREAD); 1108 } 1109 1110 static int call_class_initializer_impl_counter = 0; // for debugging 1111 1112 Method* InstanceKlass::class_initializer() { 1113 Method* clinit = find_method( 1114 vmSymbols::class_initializer_name(), vmSymbols::void_method_signature()); 1115 if (clinit != NULL && clinit->has_valid_initializer_flags()) { 1116 return clinit; 1117 } 1118 return NULL; 1119 } 1120 1121 void InstanceKlass::call_class_initializer_impl(instanceKlassHandle this_k, TRAPS) { 1122 if (ReplayCompiles && 1123 (ReplaySuppressInitializers == 1 || 1124 ReplaySuppressInitializers >= 2 && this_k->class_loader() != NULL)) { 1125 // Hide the existence of the initializer for the purpose of replaying the compile 1126 return; 1127 } 1128 1129 methodHandle h_method(THREAD, this_k->class_initializer()); 1130 assert(!this_k->is_initialized(), "we cannot initialize twice"); 1131 if (TraceClassInitialization) { 1132 tty->print("%d Initializing ", call_class_initializer_impl_counter++); 1133 this_k->name()->print_value(); 1134 tty->print_cr("%s (" INTPTR_FORMAT ")", h_method() == NULL ? "(no method)" : "", p2i(this_k())); 1135 } 1136 if (h_method() != NULL) { 1137 JavaCallArguments args; // No arguments 1138 JavaValue result(T_VOID); 1139 JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args) 1140 } 1141 } 1142 1143 1144 void InstanceKlass::mask_for(methodHandle method, int bci, 1145 InterpreterOopMap* entry_for) { 1146 // Dirty read, then double-check under a lock. 1147 if (_oop_map_cache == NULL) { 1148 // Otherwise, allocate a new one. 1149 MutexLocker x(OopMapCacheAlloc_lock); 1150 // First time use. Allocate a cache in C heap 1151 if (_oop_map_cache == NULL) { 1152 // Release stores from OopMapCache constructor before assignment 1153 // to _oop_map_cache. C++ compilers on ppc do not emit the 1154 // required memory barrier only because of the volatile 1155 // qualifier of _oop_map_cache. 1156 OrderAccess::release_store_ptr(&_oop_map_cache, new OopMapCache()); 1157 } 1158 } 1159 // _oop_map_cache is constant after init; lookup below does is own locking. 1160 _oop_map_cache->lookup(method, bci, entry_for); 1161 } 1162 1163 1164 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const { 1165 for (JavaFieldStream fs(this); !fs.done(); fs.next()) { 1166 Symbol* f_name = fs.name(); 1167 Symbol* f_sig = fs.signature(); 1168 if (f_name == name && f_sig == sig) { 1169 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index()); 1170 return true; 1171 } 1172 } 1173 return false; 1174 } 1175 1176 1177 Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const { 1178 const int n = local_interfaces()->length(); 1179 for (int i = 0; i < n; i++) { 1180 Klass* intf1 = local_interfaces()->at(i); 1181 assert(intf1->is_interface(), "just checking type"); 1182 // search for field in current interface 1183 if (InstanceKlass::cast(intf1)->find_local_field(name, sig, fd)) { 1184 assert(fd->is_static(), "interface field must be static"); 1185 return intf1; 1186 } 1187 // search for field in direct superinterfaces 1188 Klass* intf2 = InstanceKlass::cast(intf1)->find_interface_field(name, sig, fd); 1189 if (intf2 != NULL) return intf2; 1190 } 1191 // otherwise field lookup fails 1192 return NULL; 1193 } 1194 1195 1196 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const { 1197 // search order according to newest JVM spec (5.4.3.2, p.167). 1198 // 1) search for field in current klass 1199 if (find_local_field(name, sig, fd)) { 1200 return const_cast<InstanceKlass*>(this); 1201 } 1202 // 2) search for field recursively in direct superinterfaces 1203 { Klass* intf = find_interface_field(name, sig, fd); 1204 if (intf != NULL) return intf; 1205 } 1206 // 3) apply field lookup recursively if superclass exists 1207 { Klass* supr = super(); 1208 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, fd); 1209 } 1210 // 4) otherwise field lookup fails 1211 return NULL; 1212 } 1213 1214 1215 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const { 1216 // search order according to newest JVM spec (5.4.3.2, p.167). 1217 // 1) search for field in current klass 1218 if (find_local_field(name, sig, fd)) { 1219 if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this); 1220 } 1221 // 2) search for field recursively in direct superinterfaces 1222 if (is_static) { 1223 Klass* intf = find_interface_field(name, sig, fd); 1224 if (intf != NULL) return intf; 1225 } 1226 // 3) apply field lookup recursively if superclass exists 1227 { Klass* supr = super(); 1228 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, is_static, fd); 1229 } 1230 // 4) otherwise field lookup fails 1231 return NULL; 1232 } 1233 1234 1235 bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const { 1236 for (JavaFieldStream fs(this); !fs.done(); fs.next()) { 1237 if (fs.offset() == offset) { 1238 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index()); 1239 if (fd->is_static() == is_static) return true; 1240 } 1241 } 1242 return false; 1243 } 1244 1245 1246 bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const { 1247 Klass* klass = const_cast<InstanceKlass*>(this); 1248 while (klass != NULL) { 1249 if (InstanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) { 1250 return true; 1251 } 1252 klass = klass->super(); 1253 } 1254 return false; 1255 } 1256 1257 1258 void InstanceKlass::methods_do(void f(Method* method)) { 1259 // Methods aren't stable until they are loaded. This can be read outside 1260 // a lock through the ClassLoaderData for profiling 1261 if (!is_loaded()) { 1262 return; 1263 } 1264 1265 int len = methods()->length(); 1266 for (int index = 0; index < len; index++) { 1267 Method* m = methods()->at(index); 1268 assert(m->is_method(), "must be method"); 1269 f(m); 1270 } 1271 } 1272 1273 1274 void InstanceKlass::do_local_static_fields(FieldClosure* cl) { 1275 for (JavaFieldStream fs(this); !fs.done(); fs.next()) { 1276 if (fs.access_flags().is_static()) { 1277 fieldDescriptor& fd = fs.field_descriptor(); 1278 cl->do_field(&fd); 1279 } 1280 } 1281 } 1282 1283 1284 void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle mirror, TRAPS) { 1285 instanceKlassHandle h_this(THREAD, this); 1286 do_local_static_fields_impl(h_this, f, mirror, CHECK); 1287 } 1288 1289 1290 void InstanceKlass::do_local_static_fields_impl(instanceKlassHandle this_k, 1291 void f(fieldDescriptor* fd, Handle, TRAPS), Handle mirror, TRAPS) { 1292 for (JavaFieldStream fs(this_k()); !fs.done(); fs.next()) { 1293 if (fs.access_flags().is_static()) { 1294 fieldDescriptor& fd = fs.field_descriptor(); 1295 f(&fd, mirror, CHECK); 1296 } 1297 } 1298 } 1299 1300 1301 static int compare_fields_by_offset(int* a, int* b) { 1302 return a[0] - b[0]; 1303 } 1304 1305 void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) { 1306 InstanceKlass* super = superklass(); 1307 if (super != NULL) { 1308 super->do_nonstatic_fields(cl); 1309 } 1310 fieldDescriptor fd; 1311 int length = java_fields_count(); 1312 // In DebugInfo nonstatic fields are sorted by offset. 1313 int* fields_sorted = NEW_C_HEAP_ARRAY(int, 2*(length+1), mtClass); 1314 int j = 0; 1315 for (int i = 0; i < length; i += 1) { 1316 fd.reinitialize(this, i); 1317 if (!fd.is_static()) { 1318 fields_sorted[j + 0] = fd.offset(); 1319 fields_sorted[j + 1] = i; 1320 j += 2; 1321 } 1322 } 1323 if (j > 0) { 1324 length = j; 1325 // _sort_Fn is defined in growableArray.hpp. 1326 qsort(fields_sorted, length/2, 2*sizeof(int), (_sort_Fn)compare_fields_by_offset); 1327 for (int i = 0; i < length; i += 2) { 1328 fd.reinitialize(this, fields_sorted[i + 1]); 1329 assert(!fd.is_static() && fd.offset() == fields_sorted[i], "only nonstatic fields"); 1330 cl->do_field(&fd); 1331 } 1332 } 1333 FREE_C_HEAP_ARRAY(int, fields_sorted); 1334 } 1335 1336 1337 void InstanceKlass::array_klasses_do(void f(Klass* k, TRAPS), TRAPS) { 1338 if (array_klasses() != NULL) 1339 ArrayKlass::cast(array_klasses())->array_klasses_do(f, THREAD); 1340 } 1341 1342 void InstanceKlass::array_klasses_do(void f(Klass* k)) { 1343 if (array_klasses() != NULL) 1344 ArrayKlass::cast(array_klasses())->array_klasses_do(f); 1345 } 1346 1347 #ifdef ASSERT 1348 static int linear_search(Array<Method*>* methods, Symbol* name, Symbol* signature) { 1349 int len = methods->length(); 1350 for (int index = 0; index < len; index++) { 1351 Method* m = methods->at(index); 1352 assert(m->is_method(), "must be method"); 1353 if (m->signature() == signature && m->name() == name) { 1354 return index; 1355 } 1356 } 1357 return -1; 1358 } 1359 #endif 1360 1361 static int binary_search(Array<Method*>* methods, Symbol* name) { 1362 int len = methods->length(); 1363 // methods are sorted, so do binary search 1364 int l = 0; 1365 int h = len - 1; 1366 while (l <= h) { 1367 int mid = (l + h) >> 1; 1368 Method* m = methods->at(mid); 1369 assert(m->is_method(), "must be method"); 1370 int res = m->name()->fast_compare(name); 1371 if (res == 0) { 1372 return mid; 1373 } else if (res < 0) { 1374 l = mid + 1; 1375 } else { 1376 h = mid - 1; 1377 } 1378 } 1379 return -1; 1380 } 1381 1382 // find_method looks up the name/signature in the local methods array 1383 Method* InstanceKlass::find_method(Symbol* name, Symbol* signature) const { 1384 return find_method_impl(name, signature, find_overpass, find_static, find_private); 1385 } 1386 1387 Method* InstanceKlass::find_method_impl(Symbol* name, Symbol* signature, 1388 OverpassLookupMode overpass_mode, 1389 StaticLookupMode static_mode, 1390 PrivateLookupMode private_mode) const { 1391 return InstanceKlass::find_method_impl(methods(), name, signature, overpass_mode, static_mode, private_mode); 1392 } 1393 1394 // find_instance_method looks up the name/signature in the local methods array 1395 // and skips over static methods 1396 Method* InstanceKlass::find_instance_method( 1397 Array<Method*>* methods, Symbol* name, Symbol* signature) { 1398 Method* meth = InstanceKlass::find_method_impl(methods, name, signature, 1399 find_overpass, skip_static, find_private); 1400 assert(((meth == NULL) || !meth->is_static()), "find_instance_method should have skipped statics"); 1401 return meth; 1402 } 1403 1404 // find_instance_method looks up the name/signature in the local methods array 1405 // and skips over static methods 1406 Method* InstanceKlass::find_instance_method(Symbol* name, Symbol* signature) { 1407 return InstanceKlass::find_instance_method(methods(), name, signature); 1408 } 1409 1410 // Find looks up the name/signature in the local methods array 1411 // and filters on the overpass, static and private flags 1412 // This returns the first one found 1413 // note that the local methods array can have up to one overpass, one static 1414 // and one instance (private or not) with the same name/signature 1415 Method* InstanceKlass::find_local_method(Symbol* name, Symbol* signature, 1416 OverpassLookupMode overpass_mode, 1417 StaticLookupMode static_mode, 1418 PrivateLookupMode private_mode) const { 1419 return InstanceKlass::find_method_impl(methods(), name, signature, overpass_mode, static_mode, private_mode); 1420 } 1421 1422 // Find looks up the name/signature in the local methods array 1423 // and filters on the overpass, static and private flags 1424 // This returns the first one found 1425 // note that the local methods array can have up to one overpass, one static 1426 // and one instance (private or not) with the same name/signature 1427 Method* InstanceKlass::find_local_method(Array<Method*>* methods, 1428 Symbol* name, Symbol* signature, 1429 OverpassLookupMode overpass_mode, 1430 StaticLookupMode static_mode, 1431 PrivateLookupMode private_mode) { 1432 return InstanceKlass::find_method_impl(methods, name, signature, overpass_mode, static_mode, private_mode); 1433 } 1434 1435 1436 // find_method looks up the name/signature in the local methods array 1437 Method* InstanceKlass::find_method( 1438 Array<Method*>* methods, Symbol* name, Symbol* signature) { 1439 return InstanceKlass::find_method_impl(methods, name, signature, find_overpass, find_static, find_private); 1440 } 1441 1442 Method* InstanceKlass::find_method_impl( 1443 Array<Method*>* methods, Symbol* name, Symbol* signature, 1444 OverpassLookupMode overpass_mode, StaticLookupMode static_mode, 1445 PrivateLookupMode private_mode) { 1446 int hit = find_method_index(methods, name, signature, overpass_mode, static_mode, private_mode); 1447 return hit >= 0 ? methods->at(hit): NULL; 1448 } 1449 1450 bool InstanceKlass::method_matches(Method* m, Symbol* signature, bool skipping_overpass, bool skipping_static, bool skipping_private) { 1451 return ((m->signature() == signature) && 1452 (!skipping_overpass || !m->is_overpass()) && 1453 (!skipping_static || !m->is_static()) && 1454 (!skipping_private || !m->is_private())); 1455 } 1456 1457 // Used directly for default_methods to find the index into the 1458 // default_vtable_indices, and indirectly by find_method 1459 // find_method_index looks in the local methods array to return the index 1460 // of the matching name/signature. If, overpass methods are being ignored, 1461 // the search continues to find a potential non-overpass match. This capability 1462 // is important during method resolution to prefer a static method, for example, 1463 // over an overpass method. 1464 // There is the possibility in any _method's array to have the same name/signature 1465 // for a static method, an overpass method and a local instance method 1466 // To correctly catch a given method, the search criteria may need 1467 // to explicitly skip the other two. For local instance methods, it 1468 // is often necessary to skip private methods 1469 int InstanceKlass::find_method_index( 1470 Array<Method*>* methods, Symbol* name, Symbol* signature, 1471 OverpassLookupMode overpass_mode, StaticLookupMode static_mode, 1472 PrivateLookupMode private_mode) { 1473 bool skipping_overpass = (overpass_mode == skip_overpass); 1474 bool skipping_static = (static_mode == skip_static); 1475 bool skipping_private = (private_mode == skip_private); 1476 int hit = binary_search(methods, name); 1477 if (hit != -1) { 1478 Method* m = methods->at(hit); 1479 1480 // Do linear search to find matching signature. First, quick check 1481 // for common case, ignoring overpasses if requested. 1482 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) return hit; 1483 1484 // search downwards through overloaded methods 1485 int i; 1486 for (i = hit - 1; i >= 0; --i) { 1487 Method* m = methods->at(i); 1488 assert(m->is_method(), "must be method"); 1489 if (m->name() != name) break; 1490 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) return i; 1491 } 1492 // search upwards 1493 for (i = hit + 1; i < methods->length(); ++i) { 1494 Method* m = methods->at(i); 1495 assert(m->is_method(), "must be method"); 1496 if (m->name() != name) break; 1497 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) return i; 1498 } 1499 // not found 1500 #ifdef ASSERT 1501 int index = (skipping_overpass || skipping_static || skipping_private) ? -1 : linear_search(methods, name, signature); 1502 assert(index == -1, "binary search should have found entry %d", index); 1503 #endif 1504 } 1505 return -1; 1506 } 1507 int InstanceKlass::find_method_by_name(Symbol* name, int* end) { 1508 return find_method_by_name(methods(), name, end); 1509 } 1510 1511 int InstanceKlass::find_method_by_name( 1512 Array<Method*>* methods, Symbol* name, int* end_ptr) { 1513 assert(end_ptr != NULL, "just checking"); 1514 int start = binary_search(methods, name); 1515 int end = start + 1; 1516 if (start != -1) { 1517 while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start; 1518 while (end < methods->length() && (methods->at(end))->name() == name) ++end; 1519 *end_ptr = end; 1520 return start; 1521 } 1522 return -1; 1523 } 1524 1525 // uncached_lookup_method searches both the local class methods array and all 1526 // superclasses methods arrays, skipping any overpass methods in superclasses. 1527 Method* InstanceKlass::uncached_lookup_method(Symbol* name, Symbol* signature, OverpassLookupMode overpass_mode) const { 1528 OverpassLookupMode overpass_local_mode = overpass_mode; 1529 Klass* klass = const_cast<InstanceKlass*>(this); 1530 while (klass != NULL) { 1531 Method* method = InstanceKlass::cast(klass)->find_method_impl(name, signature, overpass_local_mode, find_static, find_private); 1532 if (method != NULL) { 1533 return method; 1534 } 1535 klass = InstanceKlass::cast(klass)->super(); 1536 overpass_local_mode = skip_overpass; // Always ignore overpass methods in superclasses 1537 } 1538 return NULL; 1539 } 1540 1541 #ifdef ASSERT 1542 // search through class hierarchy and return true if this class or 1543 // one of the superclasses was redefined 1544 bool InstanceKlass::has_redefined_this_or_super() const { 1545 const InstanceKlass* klass = this; 1546 while (klass != NULL) { 1547 if (klass->has_been_redefined()) { 1548 return true; 1549 } 1550 klass = InstanceKlass::cast(klass->super()); 1551 } 1552 return false; 1553 } 1554 #endif 1555 1556 // lookup a method in the default methods list then in all transitive interfaces 1557 // Do NOT return private or static methods 1558 Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name, 1559 Symbol* signature) const { 1560 Method* m = NULL; 1561 if (default_methods() != NULL) { 1562 m = find_method(default_methods(), name, signature); 1563 } 1564 // Look up interfaces 1565 if (m == NULL) { 1566 m = lookup_method_in_all_interfaces(name, signature, find_defaults); 1567 } 1568 return m; 1569 } 1570 1571 // lookup a method in all the interfaces that this class implements 1572 // Do NOT return private or static methods, new in JDK8 which are not externally visible 1573 // They should only be found in the initial InterfaceMethodRef 1574 Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name, 1575 Symbol* signature, 1576 DefaultsLookupMode defaults_mode) const { 1577 Array<Klass*>* all_ifs = transitive_interfaces(); 1578 int num_ifs = all_ifs->length(); 1579 InstanceKlass *ik = NULL; 1580 for (int i = 0; i < num_ifs; i++) { 1581 ik = InstanceKlass::cast(all_ifs->at(i)); 1582 Method* m = ik->lookup_method(name, signature); 1583 if (m != NULL && m->is_public() && !m->is_static() && 1584 ((defaults_mode != skip_defaults) || !m->is_default_method())) { 1585 return m; 1586 } 1587 } 1588 return NULL; 1589 } 1590 1591 /* jni_id_for_impl for jfieldIds only */ 1592 JNIid* InstanceKlass::jni_id_for_impl(instanceKlassHandle this_k, int offset) { 1593 MutexLocker ml(JfieldIdCreation_lock); 1594 // Retry lookup after we got the lock 1595 JNIid* probe = this_k->jni_ids() == NULL ? NULL : this_k->jni_ids()->find(offset); 1596 if (probe == NULL) { 1597 // Slow case, allocate new static field identifier 1598 probe = new JNIid(this_k(), offset, this_k->jni_ids()); 1599 this_k->set_jni_ids(probe); 1600 } 1601 return probe; 1602 } 1603 1604 1605 /* jni_id_for for jfieldIds only */ 1606 JNIid* InstanceKlass::jni_id_for(int offset) { 1607 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset); 1608 if (probe == NULL) { 1609 probe = jni_id_for_impl(this, offset); 1610 } 1611 return probe; 1612 } 1613 1614 u2 InstanceKlass::enclosing_method_data(int offset) { 1615 Array<jushort>* inner_class_list = inner_classes(); 1616 if (inner_class_list == NULL) { 1617 return 0; 1618 } 1619 int length = inner_class_list->length(); 1620 if (length % inner_class_next_offset == 0) { 1621 return 0; 1622 } else { 1623 int index = length - enclosing_method_attribute_size; 1624 assert(offset < enclosing_method_attribute_size, "invalid offset"); 1625 return inner_class_list->at(index + offset); 1626 } 1627 } 1628 1629 void InstanceKlass::set_enclosing_method_indices(u2 class_index, 1630 u2 method_index) { 1631 Array<jushort>* inner_class_list = inner_classes(); 1632 assert (inner_class_list != NULL, "_inner_classes list is not set up"); 1633 int length = inner_class_list->length(); 1634 if (length % inner_class_next_offset == enclosing_method_attribute_size) { 1635 int index = length - enclosing_method_attribute_size; 1636 inner_class_list->at_put( 1637 index + enclosing_method_class_index_offset, class_index); 1638 inner_class_list->at_put( 1639 index + enclosing_method_method_index_offset, method_index); 1640 } 1641 } 1642 1643 // Lookup or create a jmethodID. 1644 // This code is called by the VMThread and JavaThreads so the 1645 // locking has to be done very carefully to avoid deadlocks 1646 // and/or other cache consistency problems. 1647 // 1648 jmethodID InstanceKlass::get_jmethod_id(instanceKlassHandle ik_h, methodHandle method_h) { 1649 size_t idnum = (size_t)method_h->method_idnum(); 1650 jmethodID* jmeths = ik_h->methods_jmethod_ids_acquire(); 1651 size_t length = 0; 1652 jmethodID id = NULL; 1653 1654 // We use a double-check locking idiom here because this cache is 1655 // performance sensitive. In the normal system, this cache only 1656 // transitions from NULL to non-NULL which is safe because we use 1657 // release_set_methods_jmethod_ids() to advertise the new cache. 1658 // A partially constructed cache should never be seen by a racing 1659 // thread. We also use release_store_ptr() to save a new jmethodID 1660 // in the cache so a partially constructed jmethodID should never be 1661 // seen either. Cache reads of existing jmethodIDs proceed without a 1662 // lock, but cache writes of a new jmethodID requires uniqueness and 1663 // creation of the cache itself requires no leaks so a lock is 1664 // generally acquired in those two cases. 1665 // 1666 // If the RedefineClasses() API has been used, then this cache can 1667 // grow and we'll have transitions from non-NULL to bigger non-NULL. 1668 // Cache creation requires no leaks and we require safety between all 1669 // cache accesses and freeing of the old cache so a lock is generally 1670 // acquired when the RedefineClasses() API has been used. 1671 1672 if (jmeths != NULL) { 1673 // the cache already exists 1674 if (!ik_h->idnum_can_increment()) { 1675 // the cache can't grow so we can just get the current values 1676 get_jmethod_id_length_value(jmeths, idnum, &length, &id); 1677 } else { 1678 // cache can grow so we have to be more careful 1679 if (Threads::number_of_threads() == 0 || 1680 SafepointSynchronize::is_at_safepoint()) { 1681 // we're single threaded or at a safepoint - no locking needed 1682 get_jmethod_id_length_value(jmeths, idnum, &length, &id); 1683 } else { 1684 MutexLocker ml(JmethodIdCreation_lock); 1685 get_jmethod_id_length_value(jmeths, idnum, &length, &id); 1686 } 1687 } 1688 } 1689 // implied else: 1690 // we need to allocate a cache so default length and id values are good 1691 1692 if (jmeths == NULL || // no cache yet 1693 length <= idnum || // cache is too short 1694 id == NULL) { // cache doesn't contain entry 1695 1696 // This function can be called by the VMThread so we have to do all 1697 // things that might block on a safepoint before grabbing the lock. 1698 // Otherwise, we can deadlock with the VMThread or have a cache 1699 // consistency issue. These vars keep track of what we might have 1700 // to free after the lock is dropped. 1701 jmethodID to_dealloc_id = NULL; 1702 jmethodID* to_dealloc_jmeths = NULL; 1703 1704 // may not allocate new_jmeths or use it if we allocate it 1705 jmethodID* new_jmeths = NULL; 1706 if (length <= idnum) { 1707 // allocate a new cache that might be used 1708 size_t size = MAX2(idnum+1, (size_t)ik_h->idnum_allocated_count()); 1709 new_jmeths = NEW_C_HEAP_ARRAY(jmethodID, size+1, mtClass); 1710 memset(new_jmeths, 0, (size+1)*sizeof(jmethodID)); 1711 // cache size is stored in element[0], other elements offset by one 1712 new_jmeths[0] = (jmethodID)size; 1713 } 1714 1715 // allocate a new jmethodID that might be used 1716 jmethodID new_id = NULL; 1717 if (method_h->is_old() && !method_h->is_obsolete()) { 1718 // The method passed in is old (but not obsolete), we need to use the current version 1719 Method* current_method = ik_h->method_with_idnum((int)idnum); 1720 assert(current_method != NULL, "old and but not obsolete, so should exist"); 1721 new_id = Method::make_jmethod_id(ik_h->class_loader_data(), current_method); 1722 } else { 1723 // It is the current version of the method or an obsolete method, 1724 // use the version passed in 1725 new_id = Method::make_jmethod_id(ik_h->class_loader_data(), method_h()); 1726 } 1727 1728 if (Threads::number_of_threads() == 0 || 1729 SafepointSynchronize::is_at_safepoint()) { 1730 // we're single threaded or at a safepoint - no locking needed 1731 id = get_jmethod_id_fetch_or_update(ik_h, idnum, new_id, new_jmeths, 1732 &to_dealloc_id, &to_dealloc_jmeths); 1733 } else { 1734 MutexLocker ml(JmethodIdCreation_lock); 1735 id = get_jmethod_id_fetch_or_update(ik_h, idnum, new_id, new_jmeths, 1736 &to_dealloc_id, &to_dealloc_jmeths); 1737 } 1738 1739 // The lock has been dropped so we can free resources. 1740 // Free up either the old cache or the new cache if we allocated one. 1741 if (to_dealloc_jmeths != NULL) { 1742 FreeHeap(to_dealloc_jmeths); 1743 } 1744 // free up the new ID since it wasn't needed 1745 if (to_dealloc_id != NULL) { 1746 Method::destroy_jmethod_id(ik_h->class_loader_data(), to_dealloc_id); 1747 } 1748 } 1749 return id; 1750 } 1751 1752 // Figure out how many jmethodIDs haven't been allocated, and make 1753 // sure space for them is pre-allocated. This makes getting all 1754 // method ids much, much faster with classes with more than 8 1755 // methods, and has a *substantial* effect on performance with jvmti 1756 // code that loads all jmethodIDs for all classes. 1757 void InstanceKlass::ensure_space_for_methodids(int start_offset) { 1758 int new_jmeths = 0; 1759 int length = methods()->length(); 1760 for (int index = start_offset; index < length; index++) { 1761 Method* m = methods()->at(index); 1762 jmethodID id = m->find_jmethod_id_or_null(); 1763 if (id == NULL) { 1764 new_jmeths++; 1765 } 1766 } 1767 if (new_jmeths != 0) { 1768 Method::ensure_jmethod_ids(class_loader_data(), new_jmeths); 1769 } 1770 } 1771 1772 // Common code to fetch the jmethodID from the cache or update the 1773 // cache with the new jmethodID. This function should never do anything 1774 // that causes the caller to go to a safepoint or we can deadlock with 1775 // the VMThread or have cache consistency issues. 1776 // 1777 jmethodID InstanceKlass::get_jmethod_id_fetch_or_update( 1778 instanceKlassHandle ik_h, size_t idnum, jmethodID new_id, 1779 jmethodID* new_jmeths, jmethodID* to_dealloc_id_p, 1780 jmethodID** to_dealloc_jmeths_p) { 1781 assert(new_id != NULL, "sanity check"); 1782 assert(to_dealloc_id_p != NULL, "sanity check"); 1783 assert(to_dealloc_jmeths_p != NULL, "sanity check"); 1784 assert(Threads::number_of_threads() == 0 || 1785 SafepointSynchronize::is_at_safepoint() || 1786 JmethodIdCreation_lock->owned_by_self(), "sanity check"); 1787 1788 // reacquire the cache - we are locked, single threaded or at a safepoint 1789 jmethodID* jmeths = ik_h->methods_jmethod_ids_acquire(); 1790 jmethodID id = NULL; 1791 size_t length = 0; 1792 1793 if (jmeths == NULL || // no cache yet 1794 (length = (size_t)jmeths[0]) <= idnum) { // cache is too short 1795 if (jmeths != NULL) { 1796 // copy any existing entries from the old cache 1797 for (size_t index = 0; index < length; index++) { 1798 new_jmeths[index+1] = jmeths[index+1]; 1799 } 1800 *to_dealloc_jmeths_p = jmeths; // save old cache for later delete 1801 } 1802 ik_h->release_set_methods_jmethod_ids(jmeths = new_jmeths); 1803 } else { 1804 // fetch jmethodID (if any) from the existing cache 1805 id = jmeths[idnum+1]; 1806 *to_dealloc_jmeths_p = new_jmeths; // save new cache for later delete 1807 } 1808 if (id == NULL) { 1809 // No matching jmethodID in the existing cache or we have a new 1810 // cache or we just grew the cache. This cache write is done here 1811 // by the first thread to win the foot race because a jmethodID 1812 // needs to be unique once it is generally available. 1813 id = new_id; 1814 1815 // The jmethodID cache can be read while unlocked so we have to 1816 // make sure the new jmethodID is complete before installing it 1817 // in the cache. 1818 OrderAccess::release_store_ptr(&jmeths[idnum+1], id); 1819 } else { 1820 *to_dealloc_id_p = new_id; // save new id for later delete 1821 } 1822 return id; 1823 } 1824 1825 1826 // Common code to get the jmethodID cache length and the jmethodID 1827 // value at index idnum if there is one. 1828 // 1829 void InstanceKlass::get_jmethod_id_length_value(jmethodID* cache, 1830 size_t idnum, size_t *length_p, jmethodID* id_p) { 1831 assert(cache != NULL, "sanity check"); 1832 assert(length_p != NULL, "sanity check"); 1833 assert(id_p != NULL, "sanity check"); 1834 1835 // cache size is stored in element[0], other elements offset by one 1836 *length_p = (size_t)cache[0]; 1837 if (*length_p <= idnum) { // cache is too short 1838 *id_p = NULL; 1839 } else { 1840 *id_p = cache[idnum+1]; // fetch jmethodID (if any) 1841 } 1842 } 1843 1844 1845 // Lookup a jmethodID, NULL if not found. Do no blocking, no allocations, no handles 1846 jmethodID InstanceKlass::jmethod_id_or_null(Method* method) { 1847 size_t idnum = (size_t)method->method_idnum(); 1848 jmethodID* jmeths = methods_jmethod_ids_acquire(); 1849 size_t length; // length assigned as debugging crumb 1850 jmethodID id = NULL; 1851 if (jmeths != NULL && // If there is a cache 1852 (length = (size_t)jmeths[0]) > idnum) { // and if it is long enough, 1853 id = jmeths[idnum+1]; // Look up the id (may be NULL) 1854 } 1855 return id; 1856 } 1857 1858 int nmethodBucket::decrement() { 1859 return Atomic::add(-1, (volatile int *)&_count); 1860 } 1861 1862 // 1863 // Walk the list of dependent nmethods searching for nmethods which 1864 // are dependent on the changes that were passed in and mark them for 1865 // deoptimization. Returns the number of nmethods found. 1866 // 1867 int nmethodBucket::mark_dependent_nmethods(nmethodBucket* deps, DepChange& changes) { 1868 assert_locked_or_safepoint(CodeCache_lock); 1869 int found = 0; 1870 for (nmethodBucket* b = deps; b != NULL; b = b->next()) { 1871 nmethod* nm = b->get_nmethod(); 1872 // since dependencies aren't removed until an nmethod becomes a zombie, 1873 // the dependency list may contain nmethods which aren't alive. 1874 if (b->count() > 0 && nm->is_alive() && !nm->is_marked_for_deoptimization() && nm->check_dependency_on(changes)) { 1875 if (TraceDependencies) { 1876 ResourceMark rm; 1877 tty->print_cr("Marked for deoptimization"); 1878 changes.print(); 1879 nm->print(); 1880 nm->print_dependencies(); 1881 } 1882 nm->mark_for_deoptimization(); 1883 found++; 1884 } 1885 } 1886 return found; 1887 } 1888 1889 // 1890 // Add an nmethodBucket to the list of dependencies for this nmethod. 1891 // It's possible that an nmethod has multiple dependencies on this klass 1892 // so a count is kept for each bucket to guarantee that creation and 1893 // deletion of dependencies is consistent. Returns new head of the list. 1894 // 1895 nmethodBucket* nmethodBucket::add_dependent_nmethod(nmethodBucket* deps, nmethod* nm) { 1896 assert_locked_or_safepoint(CodeCache_lock); 1897 for (nmethodBucket* b = deps; b != NULL; b = b->next()) { 1898 if (nm == b->get_nmethod()) { 1899 b->increment(); 1900 return deps; 1901 } 1902 } 1903 return new nmethodBucket(nm, deps); 1904 } 1905 1906 // 1907 // Decrement count of the nmethod in the dependency list and remove 1908 // the bucket completely when the count goes to 0. This method must 1909 // find a corresponding bucket otherwise there's a bug in the 1910 // recording of dependencies. Returns true if the bucket is ready for reclamation. 1911 // 1912 bool nmethodBucket::remove_dependent_nmethod(nmethodBucket* deps, nmethod* nm) { 1913 assert_locked_or_safepoint(CodeCache_lock); 1914 1915 for (nmethodBucket* b = deps; b != NULL; b = b->next()) { 1916 if (nm == b->get_nmethod()) { 1917 int val = b->decrement(); 1918 guarantee(val >= 0, "Underflow: %d", val); 1919 return (val == 0); 1920 } 1921 } 1922 #ifdef ASSERT 1923 tty->print_raw_cr("### can't find dependent nmethod"); 1924 nm->print(); 1925 #endif // ASSERT 1926 ShouldNotReachHere(); 1927 return false; 1928 } 1929 1930 // 1931 // Reclaim all unused buckets. Returns new head of the list. 1932 // 1933 nmethodBucket* nmethodBucket::clean_dependent_nmethods(nmethodBucket* deps) { 1934 nmethodBucket* first = deps; 1935 nmethodBucket* last = NULL; 1936 nmethodBucket* b = first; 1937 1938 while (b != NULL) { 1939 assert(b->count() >= 0, "bucket count: %d", b->count()); 1940 nmethodBucket* next = b->next(); 1941 if (b->count() == 0) { 1942 if (last == NULL) { 1943 first = next; 1944 } else { 1945 last->set_next(next); 1946 } 1947 delete b; 1948 // last stays the same. 1949 } else { 1950 last = b; 1951 } 1952 b = next; 1953 } 1954 return first; 1955 } 1956 1957 #ifndef PRODUCT 1958 void nmethodBucket::print_dependent_nmethods(nmethodBucket* deps, bool verbose) { 1959 int idx = 0; 1960 for (nmethodBucket* b = deps; b != NULL; b = b->next()) { 1961 nmethod* nm = b->get_nmethod(); 1962 tty->print("[%d] count=%d { ", idx++, b->count()); 1963 if (!verbose) { 1964 nm->print_on(tty, "nmethod"); 1965 tty->print_cr(" } "); 1966 } else { 1967 nm->print(); 1968 nm->print_dependencies(); 1969 tty->print_cr("--- } "); 1970 } 1971 } 1972 } 1973 1974 bool nmethodBucket::is_dependent_nmethod(nmethodBucket* deps, nmethod* nm) { 1975 for (nmethodBucket* b = deps; b != NULL; b = b->next()) { 1976 if (nm == b->get_nmethod()) { 1977 #ifdef ASSERT 1978 int count = b->count(); 1979 assert(count >= 0, "count shouldn't be negative: %d", count); 1980 #endif 1981 return true; 1982 } 1983 } 1984 return false; 1985 } 1986 #endif //PRODUCT 1987 1988 int InstanceKlass::mark_dependent_nmethods(DepChange& changes) { 1989 assert_locked_or_safepoint(CodeCache_lock); 1990 return nmethodBucket::mark_dependent_nmethods(_dependencies, changes); 1991 } 1992 1993 void InstanceKlass::clean_dependent_nmethods() { 1994 assert_locked_or_safepoint(CodeCache_lock); 1995 1996 if (has_unloaded_dependent()) { 1997 _dependencies = nmethodBucket::clean_dependent_nmethods(_dependencies); 1998 set_has_unloaded_dependent(false); 1999 } 2000 #ifdef ASSERT 2001 else { 2002 // Verification 2003 for (nmethodBucket* b = _dependencies; b != NULL; b = b->next()) { 2004 assert(b->count() >= 0, "bucket count: %d", b->count()); 2005 assert(b->count() != 0, "empty buckets need to be cleaned"); 2006 } 2007 } 2008 #endif 2009 } 2010 2011 void InstanceKlass::add_dependent_nmethod(nmethod* nm) { 2012 assert_locked_or_safepoint(CodeCache_lock); 2013 _dependencies = nmethodBucket::add_dependent_nmethod(_dependencies, nm); 2014 } 2015 2016 void InstanceKlass::remove_dependent_nmethod(nmethod* nm) { 2017 assert_locked_or_safepoint(CodeCache_lock); 2018 2019 if (nmethodBucket::remove_dependent_nmethod(_dependencies, nm)) { 2020 set_has_unloaded_dependent(true); 2021 } 2022 } 2023 2024 #ifndef PRODUCT 2025 void InstanceKlass::print_dependent_nmethods(bool verbose) { 2026 nmethodBucket::print_dependent_nmethods(_dependencies, verbose); 2027 } 2028 2029 bool InstanceKlass::is_dependent_nmethod(nmethod* nm) { 2030 return nmethodBucket::is_dependent_nmethod(_dependencies, nm); 2031 } 2032 #endif //PRODUCT 2033 2034 void InstanceKlass::clean_implementors_list(BoolObjectClosure* is_alive) { 2035 assert(class_loader_data()->is_alive(is_alive), "this klass should be live"); 2036 if (is_interface()) { 2037 if (ClassUnloading) { 2038 Klass* impl = implementor(); 2039 if (impl != NULL) { 2040 if (!impl->is_loader_alive(is_alive)) { 2041 // remove this guy 2042 Klass** klass = adr_implementor(); 2043 assert(klass != NULL, "null klass"); 2044 if (klass != NULL) { 2045 *klass = NULL; 2046 } 2047 } 2048 } 2049 } 2050 } 2051 } 2052 2053 void InstanceKlass::clean_method_data(BoolObjectClosure* is_alive) { 2054 for (int m = 0; m < methods()->length(); m++) { 2055 MethodData* mdo = methods()->at(m)->method_data(); 2056 if (mdo != NULL) { 2057 mdo->clean_method_data(is_alive); 2058 } 2059 } 2060 } 2061 2062 2063 static void remove_unshareable_in_class(Klass* k) { 2064 // remove klass's unshareable info 2065 k->remove_unshareable_info(); 2066 } 2067 2068 void InstanceKlass::remove_unshareable_info() { 2069 Klass::remove_unshareable_info(); 2070 // Unlink the class 2071 if (is_linked()) { 2072 unlink_class(); 2073 } 2074 init_implementor(); 2075 2076 constants()->remove_unshareable_info(); 2077 2078 for (int i = 0; i < methods()->length(); i++) { 2079 Method* m = methods()->at(i); 2080 m->remove_unshareable_info(); 2081 } 2082 2083 // do array classes also. 2084 array_klasses_do(remove_unshareable_in_class); 2085 } 2086 2087 static void restore_unshareable_in_class(Klass* k, TRAPS) { 2088 // Array classes have null protection domain. 2089 // --> see ArrayKlass::complete_create_array_klass() 2090 k->restore_unshareable_info(ClassLoaderData::the_null_class_loader_data(), Handle(), CHECK); 2091 } 2092 2093 void InstanceKlass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain, TRAPS) { 2094 Klass::restore_unshareable_info(loader_data, protection_domain, CHECK); 2095 instanceKlassHandle ik(THREAD, this); 2096 2097 Array<Method*>* methods = ik->methods(); 2098 int num_methods = methods->length(); 2099 for (int index2 = 0; index2 < num_methods; ++index2) { 2100 methodHandle m(THREAD, methods->at(index2)); 2101 m->restore_unshareable_info(CHECK); 2102 } 2103 if (JvmtiExport::has_redefined_a_class()) { 2104 // Reinitialize vtable because RedefineClasses may have changed some 2105 // entries in this vtable for super classes so the CDS vtable might 2106 // point to old or obsolete entries. RedefineClasses doesn't fix up 2107 // vtables in the shared system dictionary, only the main one. 2108 // It also redefines the itable too so fix that too. 2109 ResourceMark rm(THREAD); 2110 ik->vtable()->initialize_vtable(false, CHECK); 2111 ik->itable()->initialize_itable(false, CHECK); 2112 } 2113 2114 // restore constant pool resolved references 2115 ik->constants()->restore_unshareable_info(CHECK); 2116 2117 ik->array_klasses_do(restore_unshareable_in_class, CHECK); 2118 } 2119 2120 // returns true IFF is_in_error_state() has been changed as a result of this call. 2121 bool InstanceKlass::check_sharing_error_state() { 2122 assert(DumpSharedSpaces, "should only be called during dumping"); 2123 bool old_state = is_in_error_state(); 2124 2125 if (!is_in_error_state()) { 2126 bool bad = false; 2127 for (InstanceKlass* sup = java_super(); sup; sup = sup->java_super()) { 2128 if (sup->is_in_error_state()) { 2129 bad = true; 2130 break; 2131 } 2132 } 2133 if (!bad) { 2134 Array<Klass*>* interfaces = transitive_interfaces(); 2135 for (int i = 0; i < interfaces->length(); i++) { 2136 Klass* iface = interfaces->at(i); 2137 if (InstanceKlass::cast(iface)->is_in_error_state()) { 2138 bad = true; 2139 break; 2140 } 2141 } 2142 } 2143 2144 if (bad) { 2145 set_in_error_state(); 2146 } 2147 } 2148 2149 return (old_state != is_in_error_state()); 2150 } 2151 2152 static void clear_all_breakpoints(Method* m) { 2153 m->clear_all_breakpoints(); 2154 } 2155 2156 2157 void InstanceKlass::notify_unload_class(InstanceKlass* ik) { 2158 // notify the debugger 2159 if (JvmtiExport::should_post_class_unload()) { 2160 JvmtiExport::post_class_unload(ik); 2161 } 2162 2163 // notify ClassLoadingService of class unload 2164 ClassLoadingService::notify_class_unloaded(ik); 2165 } 2166 2167 void InstanceKlass::release_C_heap_structures(InstanceKlass* ik) { 2168 // Clean up C heap 2169 ik->release_C_heap_structures(); 2170 ik->constants()->release_C_heap_structures(); 2171 } 2172 2173 void InstanceKlass::release_C_heap_structures() { 2174 2175 // Can't release the constant pool here because the constant pool can be 2176 // deallocated separately from the InstanceKlass for default methods and 2177 // redefine classes. 2178 2179 // Deallocate oop map cache 2180 if (_oop_map_cache != NULL) { 2181 delete _oop_map_cache; 2182 _oop_map_cache = NULL; 2183 } 2184 2185 // Deallocate JNI identifiers for jfieldIDs 2186 JNIid::deallocate(jni_ids()); 2187 set_jni_ids(NULL); 2188 2189 jmethodID* jmeths = methods_jmethod_ids_acquire(); 2190 if (jmeths != (jmethodID*)NULL) { 2191 release_set_methods_jmethod_ids(NULL); 2192 FreeHeap(jmeths); 2193 } 2194 2195 // Deallocate MemberNameTable 2196 { 2197 Mutex* lock_or_null = SafepointSynchronize::is_at_safepoint() ? NULL : MemberNameTable_lock; 2198 MutexLockerEx ml(lock_or_null, Mutex::_no_safepoint_check_flag); 2199 MemberNameTable* mnt = member_names(); 2200 if (mnt != NULL) { 2201 delete mnt; 2202 set_member_names(NULL); 2203 } 2204 } 2205 2206 // release dependencies 2207 nmethodBucket* b = _dependencies; 2208 _dependencies = NULL; 2209 while (b != NULL) { 2210 nmethodBucket* next = b->next(); 2211 delete b; 2212 b = next; 2213 } 2214 2215 // Deallocate breakpoint records 2216 if (breakpoints() != 0x0) { 2217 methods_do(clear_all_breakpoints); 2218 assert(breakpoints() == 0x0, "should have cleared breakpoints"); 2219 } 2220 2221 // deallocate the cached class file 2222 if (_cached_class_file != NULL) { 2223 os::free(_cached_class_file); 2224 _cached_class_file = NULL; 2225 } 2226 2227 // Decrement symbol reference counts associated with the unloaded class. 2228 if (_name != NULL) _name->decrement_refcount(); 2229 // unreference array name derived from this class name (arrays of an unloaded 2230 // class can't be referenced anymore). 2231 if (_array_name != NULL) _array_name->decrement_refcount(); 2232 if (_source_debug_extension != NULL) FREE_C_HEAP_ARRAY(char, _source_debug_extension); 2233 2234 assert(_total_instanceKlass_count >= 1, "Sanity check"); 2235 Atomic::dec(&_total_instanceKlass_count); 2236 } 2237 2238 void InstanceKlass::set_source_debug_extension(char* array, int length) { 2239 if (array == NULL) { 2240 _source_debug_extension = NULL; 2241 } else { 2242 // Adding one to the attribute length in order to store a null terminator 2243 // character could cause an overflow because the attribute length is 2244 // already coded with an u4 in the classfile, but in practice, it's 2245 // unlikely to happen. 2246 assert((length+1) > length, "Overflow checking"); 2247 char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass); 2248 for (int i = 0; i < length; i++) { 2249 sde[i] = array[i]; 2250 } 2251 sde[length] = '\0'; 2252 _source_debug_extension = sde; 2253 } 2254 } 2255 2256 address InstanceKlass::static_field_addr(int offset) { 2257 return (address)(offset + InstanceMirrorKlass::offset_of_static_fields() + cast_from_oop<intptr_t>(java_mirror())); 2258 } 2259 2260 2261 const char* InstanceKlass::signature_name() const { 2262 int hash_len = 0; 2263 char hash_buf[40]; 2264 2265 // If this is an anonymous class, append a hash to make the name unique 2266 if (is_anonymous()) { 2267 intptr_t hash = (java_mirror() != NULL) ? java_mirror()->identity_hash() : 0; 2268 jio_snprintf(hash_buf, sizeof(hash_buf), "/" UINTX_FORMAT, (uintx)hash); 2269 hash_len = (int)strlen(hash_buf); 2270 } 2271 2272 // Get the internal name as a c string 2273 const char* src = (const char*) (name()->as_C_string()); 2274 const int src_length = (int)strlen(src); 2275 2276 char* dest = NEW_RESOURCE_ARRAY(char, src_length + hash_len + 3); 2277 2278 // Add L as type indicator 2279 int dest_index = 0; 2280 dest[dest_index++] = 'L'; 2281 2282 // Add the actual class name 2283 for (int src_index = 0; src_index < src_length; ) { 2284 dest[dest_index++] = src[src_index++]; 2285 } 2286 2287 // If we have a hash, append it 2288 for (int hash_index = 0; hash_index < hash_len; ) { 2289 dest[dest_index++] = hash_buf[hash_index++]; 2290 } 2291 2292 // Add the semicolon and the NULL 2293 dest[dest_index++] = ';'; 2294 dest[dest_index] = '\0'; 2295 return dest; 2296 } 2297 2298 // different verisons of is_same_class_package 2299 bool InstanceKlass::is_same_class_package(Klass* class2) { 2300 Klass* class1 = this; 2301 oop classloader1 = InstanceKlass::cast(class1)->class_loader(); 2302 Symbol* classname1 = class1->name(); 2303 2304 if (class2->oop_is_objArray()) { 2305 class2 = ObjArrayKlass::cast(class2)->bottom_klass(); 2306 } 2307 oop classloader2; 2308 if (class2->oop_is_instance()) { 2309 classloader2 = InstanceKlass::cast(class2)->class_loader(); 2310 } else { 2311 assert(class2->oop_is_typeArray(), "should be type array"); 2312 classloader2 = NULL; 2313 } 2314 Symbol* classname2 = class2->name(); 2315 2316 return InstanceKlass::is_same_class_package(classloader1, classname1, 2317 classloader2, classname2); 2318 } 2319 2320 bool InstanceKlass::is_same_class_package(oop classloader2, Symbol* classname2) { 2321 Klass* class1 = this; 2322 oop classloader1 = InstanceKlass::cast(class1)->class_loader(); 2323 Symbol* classname1 = class1->name(); 2324 2325 return InstanceKlass::is_same_class_package(classloader1, classname1, 2326 classloader2, classname2); 2327 } 2328 2329 // return true if two classes are in the same package, classloader 2330 // and classname information is enough to determine a class's package 2331 bool InstanceKlass::is_same_class_package(oop class_loader1, Symbol* class_name1, 2332 oop class_loader2, Symbol* class_name2) { 2333 if (class_loader1 != class_loader2) { 2334 return false; 2335 } else if (class_name1 == class_name2) { 2336 return true; // skip painful bytewise comparison 2337 } else { 2338 ResourceMark rm; 2339 2340 // The Symbol*'s are in UTF8 encoding. Since we only need to check explicitly 2341 // for ASCII characters ('/', 'L', '['), we can keep them in UTF8 encoding. 2342 // Otherwise, we just compare jbyte values between the strings. 2343 const jbyte *name1 = class_name1->base(); 2344 const jbyte *name2 = class_name2->base(); 2345 2346 const jbyte *last_slash1 = UTF8::strrchr(name1, class_name1->utf8_length(), '/'); 2347 const jbyte *last_slash2 = UTF8::strrchr(name2, class_name2->utf8_length(), '/'); 2348 2349 if ((last_slash1 == NULL) || (last_slash2 == NULL)) { 2350 // One of the two doesn't have a package. Only return true 2351 // if the other one also doesn't have a package. 2352 return last_slash1 == last_slash2; 2353 } else { 2354 // Skip over '['s 2355 if (*name1 == '[') { 2356 do { 2357 name1++; 2358 } while (*name1 == '['); 2359 if (*name1 != 'L') { 2360 // Something is terribly wrong. Shouldn't be here. 2361 return false; 2362 } 2363 } 2364 if (*name2 == '[') { 2365 do { 2366 name2++; 2367 } while (*name2 == '['); 2368 if (*name2 != 'L') { 2369 // Something is terribly wrong. Shouldn't be here. 2370 return false; 2371 } 2372 } 2373 2374 // Check that package part is identical 2375 int length1 = last_slash1 - name1; 2376 int length2 = last_slash2 - name2; 2377 2378 return UTF8::equal(name1, length1, name2, length2); 2379 } 2380 } 2381 } 2382 2383 // Returns true iff super_method can be overridden by a method in targetclassname 2384 // See JSL 3rd edition 8.4.6.1 2385 // Assumes name-signature match 2386 // "this" is InstanceKlass of super_method which must exist 2387 // note that the InstanceKlass of the method in the targetclassname has not always been created yet 2388 bool InstanceKlass::is_override(methodHandle super_method, Handle targetclassloader, Symbol* targetclassname, TRAPS) { 2389 // Private methods can not be overridden 2390 if (super_method->is_private()) { 2391 return false; 2392 } 2393 // If super method is accessible, then override 2394 if ((super_method->is_protected()) || 2395 (super_method->is_public())) { 2396 return true; 2397 } 2398 // Package-private methods are not inherited outside of package 2399 assert(super_method->is_package_private(), "must be package private"); 2400 return(is_same_class_package(targetclassloader(), targetclassname)); 2401 } 2402 2403 /* defined for now in jvm.cpp, for historical reasons *-- 2404 Klass* InstanceKlass::compute_enclosing_class_impl(instanceKlassHandle self, 2405 Symbol*& simple_name_result, TRAPS) { 2406 ... 2407 } 2408 */ 2409 2410 // tell if two classes have the same enclosing class (at package level) 2411 bool InstanceKlass::is_same_package_member_impl(instanceKlassHandle class1, 2412 Klass* class2_oop, TRAPS) { 2413 if (class2_oop == class1()) return true; 2414 if (!class2_oop->oop_is_instance()) return false; 2415 instanceKlassHandle class2(THREAD, class2_oop); 2416 2417 // must be in same package before we try anything else 2418 if (!class1->is_same_class_package(class2->class_loader(), class2->name())) 2419 return false; 2420 2421 // As long as there is an outer1.getEnclosingClass, 2422 // shift the search outward. 2423 instanceKlassHandle outer1 = class1; 2424 for (;;) { 2425 // As we walk along, look for equalities between outer1 and class2. 2426 // Eventually, the walks will terminate as outer1 stops 2427 // at the top-level class around the original class. 2428 bool ignore_inner_is_member; 2429 Klass* next = outer1->compute_enclosing_class(&ignore_inner_is_member, 2430 CHECK_false); 2431 if (next == NULL) break; 2432 if (next == class2()) return true; 2433 outer1 = instanceKlassHandle(THREAD, next); 2434 } 2435 2436 // Now do the same for class2. 2437 instanceKlassHandle outer2 = class2; 2438 for (;;) { 2439 bool ignore_inner_is_member; 2440 Klass* next = outer2->compute_enclosing_class(&ignore_inner_is_member, 2441 CHECK_false); 2442 if (next == NULL) break; 2443 // Might as well check the new outer against all available values. 2444 if (next == class1()) return true; 2445 if (next == outer1()) return true; 2446 outer2 = instanceKlassHandle(THREAD, next); 2447 } 2448 2449 // If by this point we have not found an equality between the 2450 // two classes, we know they are in separate package members. 2451 return false; 2452 } 2453 2454 bool InstanceKlass::find_inner_classes_attr(instanceKlassHandle k, int* ooff, int* noff, TRAPS) { 2455 constantPoolHandle i_cp(THREAD, k->constants()); 2456 for (InnerClassesIterator iter(k); !iter.done(); iter.next()) { 2457 int ioff = iter.inner_class_info_index(); 2458 if (ioff != 0) { 2459 // Check to see if the name matches the class we're looking for 2460 // before attempting to find the class. 2461 if (i_cp->klass_name_at_matches(k, ioff)) { 2462 Klass* inner_klass = i_cp->klass_at(ioff, CHECK_false); 2463 if (k() == inner_klass) { 2464 *ooff = iter.outer_class_info_index(); 2465 *noff = iter.inner_name_index(); 2466 return true; 2467 } 2468 } 2469 } 2470 } 2471 return false; 2472 } 2473 2474 Klass* InstanceKlass::compute_enclosing_class_impl(instanceKlassHandle k, bool* inner_is_member, TRAPS) { 2475 instanceKlassHandle outer_klass; 2476 *inner_is_member = false; 2477 int ooff = 0, noff = 0; 2478 if (find_inner_classes_attr(k, &ooff, &noff, THREAD)) { 2479 constantPoolHandle i_cp(THREAD, k->constants()); 2480 if (ooff != 0) { 2481 Klass* ok = i_cp->klass_at(ooff, CHECK_NULL); 2482 outer_klass = instanceKlassHandle(THREAD, ok); 2483 *inner_is_member = true; 2484 } 2485 if (outer_klass.is_null()) { 2486 // It may be anonymous; try for that. 2487 int encl_method_class_idx = k->enclosing_method_class_index(); 2488 if (encl_method_class_idx != 0) { 2489 Klass* ok = i_cp->klass_at(encl_method_class_idx, CHECK_NULL); 2490 outer_klass = instanceKlassHandle(THREAD, ok); 2491 *inner_is_member = false; 2492 } 2493 } 2494 } 2495 2496 // If no inner class attribute found for this class. 2497 if (outer_klass.is_null()) return NULL; 2498 2499 // Throws an exception if outer klass has not declared k as an inner klass 2500 // We need evidence that each klass knows about the other, or else 2501 // the system could allow a spoof of an inner class to gain access rights. 2502 Reflection::check_for_inner_class(outer_klass, k, *inner_is_member, CHECK_NULL); 2503 return outer_klass(); 2504 } 2505 2506 jint InstanceKlass::compute_modifier_flags(TRAPS) const { 2507 jint access = access_flags().as_int(); 2508 2509 // But check if it happens to be member class. 2510 instanceKlassHandle ik(THREAD, this); 2511 InnerClassesIterator iter(ik); 2512 for (; !iter.done(); iter.next()) { 2513 int ioff = iter.inner_class_info_index(); 2514 // Inner class attribute can be zero, skip it. 2515 // Strange but true: JVM spec. allows null inner class refs. 2516 if (ioff == 0) continue; 2517 2518 // only look at classes that are already loaded 2519 // since we are looking for the flags for our self. 2520 Symbol* inner_name = ik->constants()->klass_name_at(ioff); 2521 if ((ik->name() == inner_name)) { 2522 // This is really a member class. 2523 access = iter.inner_access_flags(); 2524 break; 2525 } 2526 } 2527 // Remember to strip ACC_SUPER bit 2528 return (access & (~JVM_ACC_SUPER)) & JVM_ACC_WRITTEN_FLAGS; 2529 } 2530 2531 jint InstanceKlass::jvmti_class_status() const { 2532 jint result = 0; 2533 2534 if (is_linked()) { 2535 result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED; 2536 } 2537 2538 if (is_initialized()) { 2539 assert(is_linked(), "Class status is not consistent"); 2540 result |= JVMTI_CLASS_STATUS_INITIALIZED; 2541 } 2542 if (is_in_error_state()) { 2543 result |= JVMTI_CLASS_STATUS_ERROR; 2544 } 2545 return result; 2546 } 2547 2548 Method* InstanceKlass::method_at_itable(Klass* holder, int index, TRAPS) { 2549 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable(); 2550 int method_table_offset_in_words = ioe->offset()/wordSize; 2551 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words()) 2552 / itableOffsetEntry::size(); 2553 2554 for (int cnt = 0 ; ; cnt ++, ioe ++) { 2555 // If the interface isn't implemented by the receiver class, 2556 // the VM should throw IncompatibleClassChangeError. 2557 if (cnt >= nof_interfaces) { 2558 THROW_NULL(vmSymbols::java_lang_IncompatibleClassChangeError()); 2559 } 2560 2561 Klass* ik = ioe->interface_klass(); 2562 if (ik == holder) break; 2563 } 2564 2565 itableMethodEntry* ime = ioe->first_method_entry(this); 2566 Method* m = ime[index].method(); 2567 if (m == NULL) { 2568 THROW_NULL(vmSymbols::java_lang_AbstractMethodError()); 2569 } 2570 return m; 2571 } 2572 2573 2574 #if INCLUDE_JVMTI 2575 // update default_methods for redefineclasses for methods that are 2576 // not yet in the vtable due to concurrent subclass define and superinterface 2577 // redefinition 2578 // Note: those in the vtable, should have been updated via adjust_method_entries 2579 void InstanceKlass::adjust_default_methods(InstanceKlass* holder, bool* trace_name_printed) { 2580 // search the default_methods for uses of either obsolete or EMCP methods 2581 if (default_methods() != NULL) { 2582 for (int index = 0; index < default_methods()->length(); index ++) { 2583 Method* old_method = default_methods()->at(index); 2584 if (old_method == NULL || old_method->method_holder() != holder || !old_method->is_old()) { 2585 continue; // skip uninteresting entries 2586 } 2587 assert(!old_method->is_deleted(), "default methods may not be deleted"); 2588 2589 Method* new_method = holder->method_with_idnum(old_method->orig_method_idnum()); 2590 2591 assert(new_method != NULL, "method_with_idnum() should not be NULL"); 2592 assert(old_method != new_method, "sanity check"); 2593 2594 default_methods()->at_put(index, new_method); 2595 if (RC_TRACE_IN_RANGE(0x00100000, 0x00400000)) { 2596 if (!(*trace_name_printed)) { 2597 // RC_TRACE_MESG macro has an embedded ResourceMark 2598 RC_TRACE_MESG(("adjust: klassname=%s default methods from name=%s", 2599 external_name(), 2600 old_method->method_holder()->external_name())); 2601 *trace_name_printed = true; 2602 } 2603 RC_TRACE(0x00100000, ("default method update: %s(%s) ", 2604 new_method->name()->as_C_string(), 2605 new_method->signature()->as_C_string())); 2606 } 2607 } 2608 } 2609 } 2610 #endif // INCLUDE_JVMTI 2611 2612 // On-stack replacement stuff 2613 void InstanceKlass::add_osr_nmethod(nmethod* n) { 2614 // only one compilation can be active 2615 { 2616 // This is a short non-blocking critical region, so the no safepoint check is ok. 2617 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag); 2618 assert(n->is_osr_method(), "wrong kind of nmethod"); 2619 n->set_osr_link(osr_nmethods_head()); 2620 set_osr_nmethods_head(n); 2621 // Raise the highest osr level if necessary 2622 if (TieredCompilation) { 2623 Method* m = n->method(); 2624 m->set_highest_osr_comp_level(MAX2(m->highest_osr_comp_level(), n->comp_level())); 2625 } 2626 } 2627 2628 // Get rid of the osr methods for the same bci that have lower levels. 2629 if (TieredCompilation) { 2630 for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) { 2631 nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true); 2632 if (inv != NULL && inv->is_in_use()) { 2633 inv->make_not_entrant(); 2634 } 2635 } 2636 } 2637 } 2638 2639 2640 void InstanceKlass::remove_osr_nmethod(nmethod* n) { 2641 // This is a short non-blocking critical region, so the no safepoint check is ok. 2642 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag); 2643 assert(n->is_osr_method(), "wrong kind of nmethod"); 2644 nmethod* last = NULL; 2645 nmethod* cur = osr_nmethods_head(); 2646 int max_level = CompLevel_none; // Find the max comp level excluding n 2647 Method* m = n->method(); 2648 // Search for match 2649 while(cur != NULL && cur != n) { 2650 if (TieredCompilation && m == cur->method()) { 2651 // Find max level before n 2652 max_level = MAX2(max_level, cur->comp_level()); 2653 } 2654 last = cur; 2655 cur = cur->osr_link(); 2656 } 2657 nmethod* next = NULL; 2658 if (cur == n) { 2659 next = cur->osr_link(); 2660 if (last == NULL) { 2661 // Remove first element 2662 set_osr_nmethods_head(next); 2663 } else { 2664 last->set_osr_link(next); 2665 } 2666 } 2667 n->set_osr_link(NULL); 2668 if (TieredCompilation) { 2669 cur = next; 2670 while (cur != NULL) { 2671 // Find max level after n 2672 if (m == cur->method()) { 2673 max_level = MAX2(max_level, cur->comp_level()); 2674 } 2675 cur = cur->osr_link(); 2676 } 2677 m->set_highest_osr_comp_level(max_level); 2678 } 2679 } 2680 2681 int InstanceKlass::mark_osr_nmethods(const Method* m) { 2682 // This is a short non-blocking critical region, so the no safepoint check is ok. 2683 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag); 2684 nmethod* osr = osr_nmethods_head(); 2685 int found = 0; 2686 while (osr != NULL) { 2687 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain"); 2688 if (osr->method() == m) { 2689 osr->mark_for_deoptimization(); 2690 found++; 2691 } 2692 osr = osr->osr_link(); 2693 } 2694 return found; 2695 } 2696 2697 nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const { 2698 // This is a short non-blocking critical region, so the no safepoint check is ok. 2699 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag); 2700 nmethod* osr = osr_nmethods_head(); 2701 nmethod* best = NULL; 2702 while (osr != NULL) { 2703 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain"); 2704 // There can be a time when a c1 osr method exists but we are waiting 2705 // for a c2 version. When c2 completes its osr nmethod we will trash 2706 // the c1 version and only be able to find the c2 version. However 2707 // while we overflow in the c1 code at back branches we don't want to 2708 // try and switch to the same code as we are already running 2709 2710 if (osr->method() == m && 2711 (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) { 2712 if (match_level) { 2713 if (osr->comp_level() == comp_level) { 2714 // Found a match - return it. 2715 return osr; 2716 } 2717 } else { 2718 if (best == NULL || (osr->comp_level() > best->comp_level())) { 2719 if (osr->comp_level() == CompLevel_highest_tier) { 2720 // Found the best possible - return it. 2721 return osr; 2722 } 2723 best = osr; 2724 } 2725 } 2726 } 2727 osr = osr->osr_link(); 2728 } 2729 if (best != NULL && best->comp_level() >= comp_level && match_level == false) { 2730 return best; 2731 } 2732 return NULL; 2733 } 2734 2735 bool InstanceKlass::add_member_name(Handle mem_name) { 2736 jweak mem_name_wref = JNIHandles::make_weak_global(mem_name); 2737 MutexLocker ml(MemberNameTable_lock); 2738 DEBUG_ONLY(No_Safepoint_Verifier nsv); 2739 2740 // Check if method has been redefined while taking out MemberNameTable_lock, if so 2741 // return false. We cannot cache obsolete methods. They will crash when the function 2742 // is called! 2743 Method* method = (Method*)java_lang_invoke_MemberName::vmtarget(mem_name()); 2744 if (method->is_obsolete()) { 2745 return false; 2746 } else if (method->is_old()) { 2747 // Replace method with redefined version 2748 java_lang_invoke_MemberName::set_vmtarget(mem_name(), method_with_idnum(method->method_idnum())); 2749 } 2750 2751 if (_member_names == NULL) { 2752 _member_names = new (ResourceObj::C_HEAP, mtClass) MemberNameTable(idnum_allocated_count()); 2753 } 2754 _member_names->add_member_name(mem_name_wref); 2755 return true; 2756 } 2757 2758 // ----------------------------------------------------------------------------------------------------- 2759 // Printing 2760 2761 #ifndef PRODUCT 2762 2763 #define BULLET " - " 2764 2765 static const char* state_names[] = { 2766 "allocated", "loaded", "linked", "being_initialized", "fully_initialized", "initialization_error" 2767 }; 2768 2769 static void print_vtable(intptr_t* start, int len, outputStream* st) { 2770 for (int i = 0; i < len; i++) { 2771 intptr_t e = start[i]; 2772 st->print("%d : " INTPTR_FORMAT, i, e); 2773 if (e != 0 && ((Metadata*)e)->is_metaspace_object()) { 2774 st->print(" "); 2775 ((Metadata*)e)->print_value_on(st); 2776 } 2777 st->cr(); 2778 } 2779 } 2780 2781 void InstanceKlass::print_on(outputStream* st) const { 2782 assert(is_klass(), "must be klass"); 2783 Klass::print_on(st); 2784 2785 st->print(BULLET"instance size: %d", size_helper()); st->cr(); 2786 st->print(BULLET"klass size: %d", size()); st->cr(); 2787 st->print(BULLET"access: "); access_flags().print_on(st); st->cr(); 2788 st->print(BULLET"state: "); st->print_cr("%s", state_names[_init_state]); 2789 st->print(BULLET"name: "); name()->print_value_on(st); st->cr(); 2790 st->print(BULLET"super: "); super()->print_value_on_maybe_null(st); st->cr(); 2791 st->print(BULLET"sub: "); 2792 Klass* sub = subklass(); 2793 int n; 2794 for (n = 0; sub != NULL; n++, sub = sub->next_sibling()) { 2795 if (n < MaxSubklassPrintSize) { 2796 sub->print_value_on(st); 2797 st->print(" "); 2798 } 2799 } 2800 if (n >= MaxSubklassPrintSize) st->print("(" INTX_FORMAT " more klasses...)", n - MaxSubklassPrintSize); 2801 st->cr(); 2802 2803 if (is_interface()) { 2804 st->print_cr(BULLET"nof implementors: %d", nof_implementors()); 2805 if (nof_implementors() == 1) { 2806 st->print_cr(BULLET"implementor: "); 2807 st->print(" "); 2808 implementor()->print_value_on(st); 2809 st->cr(); 2810 } 2811 } 2812 2813 st->print(BULLET"arrays: "); array_klasses()->print_value_on_maybe_null(st); st->cr(); 2814 st->print(BULLET"methods: "); methods()->print_value_on(st); st->cr(); 2815 if (Verbose || WizardMode) { 2816 Array<Method*>* method_array = methods(); 2817 for (int i = 0; i < method_array->length(); i++) { 2818 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr(); 2819 } 2820 } 2821 st->print(BULLET"method ordering: "); method_ordering()->print_value_on(st); st->cr(); 2822 st->print(BULLET"default_methods: "); default_methods()->print_value_on(st); st->cr(); 2823 if (Verbose && default_methods() != NULL) { 2824 Array<Method*>* method_array = default_methods(); 2825 for (int i = 0; i < method_array->length(); i++) { 2826 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr(); 2827 } 2828 } 2829 if (default_vtable_indices() != NULL) { 2830 st->print(BULLET"default vtable indices: "); default_vtable_indices()->print_value_on(st); st->cr(); 2831 } 2832 st->print(BULLET"local interfaces: "); local_interfaces()->print_value_on(st); st->cr(); 2833 st->print(BULLET"trans. interfaces: "); transitive_interfaces()->print_value_on(st); st->cr(); 2834 st->print(BULLET"constants: "); constants()->print_value_on(st); st->cr(); 2835 if (class_loader_data() != NULL) { 2836 st->print(BULLET"class loader data: "); 2837 class_loader_data()->print_value_on(st); 2838 st->cr(); 2839 } 2840 st->print(BULLET"host class: "); host_klass()->print_value_on_maybe_null(st); st->cr(); 2841 if (source_file_name() != NULL) { 2842 st->print(BULLET"source file: "); 2843 source_file_name()->print_value_on(st); 2844 st->cr(); 2845 } 2846 if (source_debug_extension() != NULL) { 2847 st->print(BULLET"source debug extension: "); 2848 st->print("%s", source_debug_extension()); 2849 st->cr(); 2850 } 2851 st->print(BULLET"class annotations: "); class_annotations()->print_value_on(st); st->cr(); 2852 st->print(BULLET"class type annotations: "); class_type_annotations()->print_value_on(st); st->cr(); 2853 st->print(BULLET"field annotations: "); fields_annotations()->print_value_on(st); st->cr(); 2854 st->print(BULLET"field type annotations: "); fields_type_annotations()->print_value_on(st); st->cr(); 2855 { 2856 bool have_pv = false; 2857 // previous versions are linked together through the InstanceKlass 2858 for (InstanceKlass* pv_node = _previous_versions; 2859 pv_node != NULL; 2860 pv_node = pv_node->previous_versions()) { 2861 if (!have_pv) 2862 st->print(BULLET"previous version: "); 2863 have_pv = true; 2864 pv_node->constants()->print_value_on(st); 2865 } 2866 if (have_pv) st->cr(); 2867 } 2868 2869 if (generic_signature() != NULL) { 2870 st->print(BULLET"generic signature: "); 2871 generic_signature()->print_value_on(st); 2872 st->cr(); 2873 } 2874 st->print(BULLET"inner classes: "); inner_classes()->print_value_on(st); st->cr(); 2875 st->print(BULLET"java mirror: "); java_mirror()->print_value_on(st); st->cr(); 2876 st->print(BULLET"vtable length %d (start addr: " INTPTR_FORMAT ")", vtable_length(), p2i(start_of_vtable())); st->cr(); 2877 if (vtable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_vtable(), vtable_length(), st); 2878 st->print(BULLET"itable length %d (start addr: " INTPTR_FORMAT ")", itable_length(), p2i(start_of_itable())); st->cr(); 2879 if (itable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_itable(), itable_length(), st); 2880 st->print_cr(BULLET"---- static fields (%d words):", static_field_size()); 2881 FieldPrinter print_static_field(st); 2882 ((InstanceKlass*)this)->do_local_static_fields(&print_static_field); 2883 st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size()); 2884 FieldPrinter print_nonstatic_field(st); 2885 ((InstanceKlass*)this)->do_nonstatic_fields(&print_nonstatic_field); 2886 2887 st->print(BULLET"non-static oop maps: "); 2888 OopMapBlock* map = start_of_nonstatic_oop_maps(); 2889 OopMapBlock* end_map = map + nonstatic_oop_map_count(); 2890 while (map < end_map) { 2891 st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1)); 2892 map++; 2893 } 2894 st->cr(); 2895 } 2896 2897 #endif //PRODUCT 2898 2899 void InstanceKlass::print_value_on(outputStream* st) const { 2900 assert(is_klass(), "must be klass"); 2901 if (Verbose || WizardMode) access_flags().print_on(st); 2902 name()->print_value_on(st); 2903 } 2904 2905 #ifndef PRODUCT 2906 2907 void FieldPrinter::do_field(fieldDescriptor* fd) { 2908 _st->print(BULLET); 2909 if (_obj == NULL) { 2910 fd->print_on(_st); 2911 _st->cr(); 2912 } else { 2913 fd->print_on_for(_st, _obj); 2914 _st->cr(); 2915 } 2916 } 2917 2918 2919 void InstanceKlass::oop_print_on(oop obj, outputStream* st) { 2920 Klass::oop_print_on(obj, st); 2921 2922 if (this == SystemDictionary::String_klass()) { 2923 typeArrayOop value = java_lang_String::value(obj); 2924 juint offset = java_lang_String::offset(obj); 2925 juint length = java_lang_String::length(obj); 2926 if (value != NULL && 2927 value->is_typeArray() && 2928 offset <= (juint) value->length() && 2929 offset + length <= (juint) value->length()) { 2930 st->print(BULLET"string: "); 2931 java_lang_String::print(obj, st); 2932 st->cr(); 2933 if (!WizardMode) return; // that is enough 2934 } 2935 } 2936 2937 st->print_cr(BULLET"---- fields (total size %d words):", oop_size(obj)); 2938 FieldPrinter print_field(st, obj); 2939 do_nonstatic_fields(&print_field); 2940 2941 if (this == SystemDictionary::Class_klass()) { 2942 st->print(BULLET"signature: "); 2943 java_lang_Class::print_signature(obj, st); 2944 st->cr(); 2945 Klass* mirrored_klass = java_lang_Class::as_Klass(obj); 2946 st->print(BULLET"fake entry for mirror: "); 2947 mirrored_klass->print_value_on_maybe_null(st); 2948 st->cr(); 2949 Klass* array_klass = java_lang_Class::array_klass(obj); 2950 st->print(BULLET"fake entry for array: "); 2951 array_klass->print_value_on_maybe_null(st); 2952 st->cr(); 2953 st->print_cr(BULLET"fake entry for oop_size: %d", java_lang_Class::oop_size(obj)); 2954 st->print_cr(BULLET"fake entry for static_oop_field_count: %d", java_lang_Class::static_oop_field_count(obj)); 2955 Klass* real_klass = java_lang_Class::as_Klass(obj); 2956 if (real_klass != NULL && real_klass->oop_is_instance()) { 2957 InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field); 2958 } 2959 } else if (this == SystemDictionary::MethodType_klass()) { 2960 st->print(BULLET"signature: "); 2961 java_lang_invoke_MethodType::print_signature(obj, st); 2962 st->cr(); 2963 } 2964 } 2965 2966 #endif //PRODUCT 2967 2968 void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) { 2969 st->print("a "); 2970 name()->print_value_on(st); 2971 obj->print_address_on(st); 2972 if (this == SystemDictionary::String_klass() 2973 && java_lang_String::value(obj) != NULL) { 2974 ResourceMark rm; 2975 int len = java_lang_String::length(obj); 2976 int plen = (len < 24 ? len : 12); 2977 char* str = java_lang_String::as_utf8_string(obj, 0, plen); 2978 st->print(" = \"%s\"", str); 2979 if (len > plen) 2980 st->print("...[%d]", len); 2981 } else if (this == SystemDictionary::Class_klass()) { 2982 Klass* k = java_lang_Class::as_Klass(obj); 2983 st->print(" = "); 2984 if (k != NULL) { 2985 k->print_value_on(st); 2986 } else { 2987 const char* tname = type2name(java_lang_Class::primitive_type(obj)); 2988 st->print("%s", tname ? tname : "type?"); 2989 } 2990 } else if (this == SystemDictionary::MethodType_klass()) { 2991 st->print(" = "); 2992 java_lang_invoke_MethodType::print_signature(obj, st); 2993 } else if (java_lang_boxing_object::is_instance(obj)) { 2994 st->print(" = "); 2995 java_lang_boxing_object::print(obj, st); 2996 } else if (this == SystemDictionary::LambdaForm_klass()) { 2997 oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj); 2998 if (vmentry != NULL) { 2999 st->print(" => "); 3000 vmentry->print_value_on(st); 3001 } 3002 } else if (this == SystemDictionary::MemberName_klass()) { 3003 Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj); 3004 if (vmtarget != NULL) { 3005 st->print(" = "); 3006 vmtarget->print_value_on(st); 3007 } else { 3008 java_lang_invoke_MemberName::clazz(obj)->print_value_on(st); 3009 st->print("."); 3010 java_lang_invoke_MemberName::name(obj)->print_value_on(st); 3011 } 3012 } 3013 } 3014 3015 const char* InstanceKlass::internal_name() const { 3016 return external_name(); 3017 } 3018 3019 #if INCLUDE_SERVICES 3020 // Size Statistics 3021 void InstanceKlass::collect_statistics(KlassSizeStats *sz) const { 3022 Klass::collect_statistics(sz); 3023 3024 sz->_inst_size = HeapWordSize * size_helper(); 3025 sz->_vtab_bytes = HeapWordSize * align_object_offset(vtable_length()); 3026 sz->_itab_bytes = HeapWordSize * align_object_offset(itable_length()); 3027 sz->_nonstatic_oopmap_bytes = HeapWordSize * 3028 ((is_interface() || is_anonymous()) ? 3029 align_object_offset(nonstatic_oop_map_size()) : 3030 nonstatic_oop_map_size()); 3031 3032 int n = 0; 3033 n += (sz->_methods_array_bytes = sz->count_array(methods())); 3034 n += (sz->_method_ordering_bytes = sz->count_array(method_ordering())); 3035 n += (sz->_local_interfaces_bytes = sz->count_array(local_interfaces())); 3036 n += (sz->_transitive_interfaces_bytes = sz->count_array(transitive_interfaces())); 3037 n += (sz->_fields_bytes = sz->count_array(fields())); 3038 n += (sz->_inner_classes_bytes = sz->count_array(inner_classes())); 3039 sz->_ro_bytes += n; 3040 3041 const ConstantPool* cp = constants(); 3042 if (cp) { 3043 cp->collect_statistics(sz); 3044 } 3045 3046 const Annotations* anno = annotations(); 3047 if (anno) { 3048 anno->collect_statistics(sz); 3049 } 3050 3051 const Array<Method*>* methods_array = methods(); 3052 if (methods()) { 3053 for (int i = 0; i < methods_array->length(); i++) { 3054 Method* method = methods_array->at(i); 3055 if (method) { 3056 sz->_method_count ++; 3057 method->collect_statistics(sz); 3058 } 3059 } 3060 } 3061 } 3062 #endif // INCLUDE_SERVICES 3063 3064 // Verification 3065 3066 class VerifyFieldClosure: public OopClosure { 3067 protected: 3068 template <class T> void do_oop_work(T* p) { 3069 oop obj = oopDesc::load_decode_heap_oop(p); 3070 if (!obj->is_oop_or_null()) { 3071 tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p2i(p), p2i(obj)); 3072 Universe::print(); 3073 guarantee(false, "boom"); 3074 } 3075 } 3076 public: 3077 virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); } 3078 virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); } 3079 }; 3080 3081 void InstanceKlass::verify_on(outputStream* st) { 3082 #ifndef PRODUCT 3083 // Avoid redundant verifies, this really should be in product. 3084 if (_verify_count == Universe::verify_count()) return; 3085 _verify_count = Universe::verify_count(); 3086 #endif 3087 3088 // Verify Klass 3089 Klass::verify_on(st); 3090 3091 // Verify that klass is present in ClassLoaderData 3092 guarantee(class_loader_data()->contains_klass(this), 3093 "this class isn't found in class loader data"); 3094 3095 // Verify vtables 3096 if (is_linked()) { 3097 ResourceMark rm; 3098 // $$$ This used to be done only for m/s collections. Doing it 3099 // always seemed a valid generalization. (DLD -- 6/00) 3100 vtable()->verify(st); 3101 } 3102 3103 // Verify first subklass 3104 if (subklass() != NULL) { 3105 guarantee(subklass()->is_klass(), "should be klass"); 3106 } 3107 3108 // Verify siblings 3109 Klass* super = this->super(); 3110 Klass* sib = next_sibling(); 3111 if (sib != NULL) { 3112 if (sib == this) { 3113 fatal("subclass points to itself " PTR_FORMAT, p2i(sib)); 3114 } 3115 3116 guarantee(sib->is_klass(), "should be klass"); 3117 guarantee(sib->super() == super, "siblings should have same superklass"); 3118 } 3119 3120 // Verify implementor fields 3121 Klass* im = implementor(); 3122 if (im != NULL) { 3123 guarantee(is_interface(), "only interfaces should have implementor set"); 3124 guarantee(im->is_klass(), "should be klass"); 3125 guarantee(!im->is_interface() || im == this, 3126 "implementors cannot be interfaces"); 3127 } 3128 3129 // Verify local interfaces 3130 if (local_interfaces()) { 3131 Array<Klass*>* local_interfaces = this->local_interfaces(); 3132 for (int j = 0; j < local_interfaces->length(); j++) { 3133 Klass* e = local_interfaces->at(j); 3134 guarantee(e->is_klass() && e->is_interface(), "invalid local interface"); 3135 } 3136 } 3137 3138 // Verify transitive interfaces 3139 if (transitive_interfaces() != NULL) { 3140 Array<Klass*>* transitive_interfaces = this->transitive_interfaces(); 3141 for (int j = 0; j < transitive_interfaces->length(); j++) { 3142 Klass* e = transitive_interfaces->at(j); 3143 guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface"); 3144 } 3145 } 3146 3147 // Verify methods 3148 if (methods() != NULL) { 3149 Array<Method*>* methods = this->methods(); 3150 for (int j = 0; j < methods->length(); j++) { 3151 guarantee(methods->at(j)->is_method(), "non-method in methods array"); 3152 } 3153 for (int j = 0; j < methods->length() - 1; j++) { 3154 Method* m1 = methods->at(j); 3155 Method* m2 = methods->at(j + 1); 3156 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly"); 3157 } 3158 } 3159 3160 // Verify method ordering 3161 if (method_ordering() != NULL) { 3162 Array<int>* method_ordering = this->method_ordering(); 3163 int length = method_ordering->length(); 3164 if (JvmtiExport::can_maintain_original_method_order() || 3165 ((UseSharedSpaces || DumpSharedSpaces) && length != 0)) { 3166 guarantee(length == methods()->length(), "invalid method ordering length"); 3167 jlong sum = 0; 3168 for (int j = 0; j < length; j++) { 3169 int original_index = method_ordering->at(j); 3170 guarantee(original_index >= 0, "invalid method ordering index"); 3171 guarantee(original_index < length, "invalid method ordering index"); 3172 sum += original_index; 3173 } 3174 // Verify sum of indices 0,1,...,length-1 3175 guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum"); 3176 } else { 3177 guarantee(length == 0, "invalid method ordering length"); 3178 } 3179 } 3180 3181 // Verify default methods 3182 if (default_methods() != NULL) { 3183 Array<Method*>* methods = this->default_methods(); 3184 for (int j = 0; j < methods->length(); j++) { 3185 guarantee(methods->at(j)->is_method(), "non-method in methods array"); 3186 } 3187 for (int j = 0; j < methods->length() - 1; j++) { 3188 Method* m1 = methods->at(j); 3189 Method* m2 = methods->at(j + 1); 3190 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly"); 3191 } 3192 } 3193 3194 // Verify JNI static field identifiers 3195 if (jni_ids() != NULL) { 3196 jni_ids()->verify(this); 3197 } 3198 3199 // Verify other fields 3200 if (array_klasses() != NULL) { 3201 guarantee(array_klasses()->is_klass(), "should be klass"); 3202 } 3203 if (constants() != NULL) { 3204 guarantee(constants()->is_constantPool(), "should be constant pool"); 3205 } 3206 const Klass* host = host_klass(); 3207 if (host != NULL) { 3208 guarantee(host->is_klass(), "should be klass"); 3209 } 3210 } 3211 3212 void InstanceKlass::oop_verify_on(oop obj, outputStream* st) { 3213 Klass::oop_verify_on(obj, st); 3214 VerifyFieldClosure blk; 3215 obj->oop_iterate_no_header(&blk); 3216 } 3217 3218 3219 // JNIid class for jfieldIDs only 3220 // Note to reviewers: 3221 // These JNI functions are just moved over to column 1 and not changed 3222 // in the compressed oops workspace. 3223 JNIid::JNIid(Klass* holder, int offset, JNIid* next) { 3224 _holder = holder; 3225 _offset = offset; 3226 _next = next; 3227 debug_only(_is_static_field_id = false;) 3228 } 3229 3230 3231 JNIid* JNIid::find(int offset) { 3232 JNIid* current = this; 3233 while (current != NULL) { 3234 if (current->offset() == offset) return current; 3235 current = current->next(); 3236 } 3237 return NULL; 3238 } 3239 3240 void JNIid::deallocate(JNIid* current) { 3241 while (current != NULL) { 3242 JNIid* next = current->next(); 3243 delete current; 3244 current = next; 3245 } 3246 } 3247 3248 3249 void JNIid::verify(Klass* holder) { 3250 int first_field_offset = InstanceMirrorKlass::offset_of_static_fields(); 3251 int end_field_offset; 3252 end_field_offset = first_field_offset + (InstanceKlass::cast(holder)->static_field_size() * wordSize); 3253 3254 JNIid* current = this; 3255 while (current != NULL) { 3256 guarantee(current->holder() == holder, "Invalid klass in JNIid"); 3257 #ifdef ASSERT 3258 int o = current->offset(); 3259 if (current->is_static_field_id()) { 3260 guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid"); 3261 } 3262 #endif 3263 current = current->next(); 3264 } 3265 } 3266 3267 3268 #ifdef ASSERT 3269 void InstanceKlass::set_init_state(ClassState state) { 3270 bool good_state = is_shared() ? (_init_state <= state) 3271 : (_init_state < state); 3272 assert(good_state || state == allocated, "illegal state transition"); 3273 _init_state = (u1)state; 3274 } 3275 #endif 3276 3277 3278 3279 // RedefineClasses() support for previous versions: 3280 int InstanceKlass::_previous_version_count = 0; 3281 3282 // Purge previous versions before adding new previous versions of the class. 3283 void InstanceKlass::purge_previous_versions(InstanceKlass* ik) { 3284 if (ik->previous_versions() != NULL) { 3285 // This klass has previous versions so see what we can cleanup 3286 // while it is safe to do so. 3287 3288 int deleted_count = 0; // leave debugging breadcrumbs 3289 int live_count = 0; 3290 ClassLoaderData* loader_data = ik->class_loader_data(); 3291 assert(loader_data != NULL, "should never be null"); 3292 3293 // RC_TRACE macro has an embedded ResourceMark 3294 RC_TRACE(0x00000200, ("purge: %s: previous versions", ik->external_name())); 3295 3296 // previous versions are linked together through the InstanceKlass 3297 InstanceKlass* pv_node = ik->previous_versions(); 3298 InstanceKlass* last = ik; 3299 int version = 0; 3300 3301 // check the previous versions list 3302 for (; pv_node != NULL; ) { 3303 3304 ConstantPool* pvcp = pv_node->constants(); 3305 assert(pvcp != NULL, "cp ref was unexpectedly cleared"); 3306 3307 if (!pvcp->on_stack()) { 3308 // If the constant pool isn't on stack, none of the methods 3309 // are executing. Unlink this previous_version. 3310 // The previous version InstanceKlass is on the ClassLoaderData deallocate list 3311 // so will be deallocated during the next phase of class unloading. 3312 RC_TRACE(0x00000200, ("purge: previous version " INTPTR_FORMAT " is dead", 3313 p2i(pv_node))); 3314 // For debugging purposes. 3315 pv_node->set_is_scratch_class(); 3316 pv_node->class_loader_data()->add_to_deallocate_list(pv_node); 3317 pv_node = pv_node->previous_versions(); 3318 last->link_previous_versions(pv_node); 3319 deleted_count++; 3320 version++; 3321 continue; 3322 } else { 3323 RC_TRACE(0x00000200, ("purge: previous version " INTPTR_FORMAT " is alive", 3324 p2i(pv_node))); 3325 assert(pvcp->pool_holder() != NULL, "Constant pool with no holder"); 3326 guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack"); 3327 live_count++; 3328 } 3329 3330 // At least one method is live in this previous version. 3331 // Reset dead EMCP methods not to get breakpoints. 3332 // All methods are deallocated when all of the methods for this class are no 3333 // longer running. 3334 Array<Method*>* method_refs = pv_node->methods(); 3335 if (method_refs != NULL) { 3336 RC_TRACE(0x00000200, ("purge: previous methods length=%d", 3337 method_refs->length())); 3338 for (int j = 0; j < method_refs->length(); j++) { 3339 Method* method = method_refs->at(j); 3340 3341 if (!method->on_stack()) { 3342 // no breakpoints for non-running methods 3343 if (method->is_running_emcp()) { 3344 method->set_running_emcp(false); 3345 } 3346 } else { 3347 assert (method->is_obsolete() || method->is_running_emcp(), 3348 "emcp method cannot run after emcp bit is cleared"); 3349 // RC_TRACE macro has an embedded ResourceMark 3350 RC_TRACE(0x00000200, 3351 ("purge: %s(%s): prev method @%d in version @%d is alive", 3352 method->name()->as_C_string(), 3353 method->signature()->as_C_string(), j, version)); 3354 } 3355 } 3356 } 3357 // next previous version 3358 last = pv_node; 3359 pv_node = pv_node->previous_versions(); 3360 version++; 3361 } 3362 RC_TRACE(0x00000200, 3363 ("purge: previous version stats: live=%d, deleted=%d", live_count, 3364 deleted_count)); 3365 } 3366 } 3367 3368 void InstanceKlass::mark_newly_obsolete_methods(Array<Method*>* old_methods, 3369 int emcp_method_count) { 3370 int obsolete_method_count = old_methods->length() - emcp_method_count; 3371 3372 if (emcp_method_count != 0 && obsolete_method_count != 0 && 3373 _previous_versions != NULL) { 3374 // We have a mix of obsolete and EMCP methods so we have to 3375 // clear out any matching EMCP method entries the hard way. 3376 int local_count = 0; 3377 for (int i = 0; i < old_methods->length(); i++) { 3378 Method* old_method = old_methods->at(i); 3379 if (old_method->is_obsolete()) { 3380 // only obsolete methods are interesting 3381 Symbol* m_name = old_method->name(); 3382 Symbol* m_signature = old_method->signature(); 3383 3384 // previous versions are linked together through the InstanceKlass 3385 int j = 0; 3386 for (InstanceKlass* prev_version = _previous_versions; 3387 prev_version != NULL; 3388 prev_version = prev_version->previous_versions(), j++) { 3389 3390 Array<Method*>* method_refs = prev_version->methods(); 3391 for (int k = 0; k < method_refs->length(); k++) { 3392 Method* method = method_refs->at(k); 3393 3394 if (!method->is_obsolete() && 3395 method->name() == m_name && 3396 method->signature() == m_signature) { 3397 // The current RedefineClasses() call has made all EMCP 3398 // versions of this method obsolete so mark it as obsolete 3399 RC_TRACE(0x00000400, 3400 ("add: %s(%s): flush obsolete method @%d in version @%d", 3401 m_name->as_C_string(), m_signature->as_C_string(), k, j)); 3402 3403 method->set_is_obsolete(); 3404 break; 3405 } 3406 } 3407 3408 // The previous loop may not find a matching EMCP method, but 3409 // that doesn't mean that we can optimize and not go any 3410 // further back in the PreviousVersion generations. The EMCP 3411 // method for this generation could have already been made obsolete, 3412 // but there still may be an older EMCP method that has not 3413 // been made obsolete. 3414 } 3415 3416 if (++local_count >= obsolete_method_count) { 3417 // no more obsolete methods so bail out now 3418 break; 3419 } 3420 } 3421 } 3422 } 3423 } 3424 3425 // Save the scratch_class as the previous version if any of the methods are running. 3426 // The previous_versions are used to set breakpoints in EMCP methods and they are 3427 // also used to clean MethodData links to redefined methods that are no longer running. 3428 void InstanceKlass::add_previous_version(instanceKlassHandle scratch_class, 3429 int emcp_method_count) { 3430 assert(Thread::current()->is_VM_thread(), 3431 "only VMThread can add previous versions"); 3432 3433 // RC_TRACE macro has an embedded ResourceMark 3434 RC_TRACE(0x00000400, ("adding previous version ref for %s, EMCP_cnt=%d", 3435 scratch_class->external_name(), emcp_method_count)); 3436 3437 // Clean out old previous versions 3438 purge_previous_versions(this); 3439 3440 // Mark newly obsolete methods in remaining previous versions. An EMCP method from 3441 // a previous redefinition may be made obsolete by this redefinition. 3442 Array<Method*>* old_methods = scratch_class->methods(); 3443 mark_newly_obsolete_methods(old_methods, emcp_method_count); 3444 3445 // If the constant pool for this previous version of the class 3446 // is not marked as being on the stack, then none of the methods 3447 // in this previous version of the class are on the stack so 3448 // we don't need to add this as a previous version. 3449 ConstantPool* cp_ref = scratch_class->constants(); 3450 if (!cp_ref->on_stack()) { 3451 RC_TRACE(0x00000400, ("add: scratch class not added; no methods are running")); 3452 // For debugging purposes. 3453 scratch_class->set_is_scratch_class(); 3454 scratch_class->class_loader_data()->add_to_deallocate_list(scratch_class()); 3455 // Update count for class unloading. 3456 _previous_version_count--; 3457 return; 3458 } 3459 3460 if (emcp_method_count != 0) { 3461 // At least one method is still running, check for EMCP methods 3462 for (int i = 0; i < old_methods->length(); i++) { 3463 Method* old_method = old_methods->at(i); 3464 if (!old_method->is_obsolete() && old_method->on_stack()) { 3465 // if EMCP method (not obsolete) is on the stack, mark as EMCP so that 3466 // we can add breakpoints for it. 3467 3468 // We set the method->on_stack bit during safepoints for class redefinition 3469 // and use this bit to set the is_running_emcp bit. 3470 // After the safepoint, the on_stack bit is cleared and the running emcp 3471 // method may exit. If so, we would set a breakpoint in a method that 3472 // is never reached, but this won't be noticeable to the programmer. 3473 old_method->set_running_emcp(true); 3474 RC_TRACE(0x00000400, ("add: EMCP method %s is on_stack " INTPTR_FORMAT, 3475 old_method->name_and_sig_as_C_string(), p2i(old_method))); 3476 } else if (!old_method->is_obsolete()) { 3477 RC_TRACE(0x00000400, ("add: EMCP method %s is NOT on_stack " INTPTR_FORMAT, 3478 old_method->name_and_sig_as_C_string(), p2i(old_method))); 3479 } 3480 } 3481 } 3482 3483 // Add previous version if any methods are still running. 3484 RC_TRACE(0x00000400, ("add: scratch class added; one of its methods is on_stack")); 3485 assert(scratch_class->previous_versions() == NULL, "shouldn't have a previous version"); 3486 scratch_class->link_previous_versions(previous_versions()); 3487 link_previous_versions(scratch_class()); 3488 // Update count for class unloading. 3489 _previous_version_count++; 3490 } // end add_previous_version() 3491 3492 3493 Method* InstanceKlass::method_with_idnum(int idnum) { 3494 Method* m = NULL; 3495 if (idnum < methods()->length()) { 3496 m = methods()->at(idnum); 3497 } 3498 if (m == NULL || m->method_idnum() != idnum) { 3499 for (int index = 0; index < methods()->length(); ++index) { 3500 m = methods()->at(index); 3501 if (m->method_idnum() == idnum) { 3502 return m; 3503 } 3504 } 3505 // None found, return null for the caller to handle. 3506 return NULL; 3507 } 3508 return m; 3509 } 3510 3511 3512 Method* InstanceKlass::method_with_orig_idnum(int idnum) { 3513 if (idnum >= methods()->length()) { 3514 return NULL; 3515 } 3516 Method* m = methods()->at(idnum); 3517 if (m != NULL && m->orig_method_idnum() == idnum) { 3518 return m; 3519 } 3520 // Obsolete method idnum does not match the original idnum 3521 for (int index = 0; index < methods()->length(); ++index) { 3522 m = methods()->at(index); 3523 if (m->orig_method_idnum() == idnum) { 3524 return m; 3525 } 3526 } 3527 // None found, return null for the caller to handle. 3528 return NULL; 3529 } 3530 3531 3532 Method* InstanceKlass::method_with_orig_idnum(int idnum, int version) { 3533 InstanceKlass* holder = get_klass_version(version); 3534 if (holder == NULL) { 3535 return NULL; // The version of klass is gone, no method is found 3536 } 3537 Method* method = holder->method_with_orig_idnum(idnum); 3538 return method; 3539 } 3540 3541 3542 jint InstanceKlass::get_cached_class_file_len() { 3543 return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file); 3544 } 3545 3546 unsigned char * InstanceKlass::get_cached_class_file_bytes() { 3547 return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file); 3548 }