instanceKlass.cpp revision 6646:b596a1063e90
1/* 2 * Copyright (c) 1997, 2014, 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_implementation/shared/markSweep.inline.hpp" 32#include "gc_interface/collectedHeap.inline.hpp" 33#include "interpreter/oopMapCache.hpp" 34#include "interpreter/rewriter.hpp" 35#include "jvmtifiles/jvmti.h" 36#include "memory/genOopClosures.inline.hpp" 37#include "memory/heapInspection.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.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/jvmtiRedefineClassesTrace.hpp" 51#include "prims/jvmtiRedefineClasses.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#if INCLUDE_ALL_GCS 66#include "gc_implementation/concurrentMarkSweep/cmsOopClosures.inline.hpp" 67#include "gc_implementation/g1/g1CollectedHeap.inline.hpp" 68#include "gc_implementation/g1/g1OopClosures.inline.hpp" 69#include "gc_implementation/g1/g1RemSet.inline.hpp" 70#include "gc_implementation/g1/heapRegionSeq.inline.hpp" 71#include "gc_implementation/parNew/parOopClosures.inline.hpp" 72#include "gc_implementation/parallelScavenge/parallelScavengeHeap.inline.hpp" 73#include "gc_implementation/parallelScavenge/psPromotionManager.inline.hpp" 74#include "gc_implementation/parallelScavenge/psScavenge.inline.hpp" 75#include "oops/oop.pcgc.inline.hpp" 76#endif // INCLUDE_ALL_GCS 77#ifdef COMPILER1 78#include "c1/c1_Compiler.hpp" 79#endif 80 81PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC 82 83#ifdef DTRACE_ENABLED 84 85 86#define HOTSPOT_CLASS_INITIALIZATION_required HOTSPOT_CLASS_INITIALIZATION_REQUIRED 87#define HOTSPOT_CLASS_INITIALIZATION_recursive HOTSPOT_CLASS_INITIALIZATION_RECURSIVE 88#define HOTSPOT_CLASS_INITIALIZATION_concurrent HOTSPOT_CLASS_INITIALIZATION_CONCURRENT 89#define HOTSPOT_CLASS_INITIALIZATION_erroneous HOTSPOT_CLASS_INITIALIZATION_ERRONEOUS 90#define HOTSPOT_CLASS_INITIALIZATION_super__failed HOTSPOT_CLASS_INITIALIZATION_SUPER_FAILED 91#define HOTSPOT_CLASS_INITIALIZATION_clinit HOTSPOT_CLASS_INITIALIZATION_CLINIT 92#define HOTSPOT_CLASS_INITIALIZATION_error HOTSPOT_CLASS_INITIALIZATION_ERROR 93#define HOTSPOT_CLASS_INITIALIZATION_end HOTSPOT_CLASS_INITIALIZATION_END 94#define DTRACE_CLASSINIT_PROBE(type, clss, thread_type) \ 95 { \ 96 char* data = NULL; \ 97 int len = 0; \ 98 Symbol* name = (clss)->name(); \ 99 if (name != NULL) { \ 100 data = (char*)name->bytes(); \ 101 len = name->utf8_length(); \ 102 } \ 103 HOTSPOT_CLASS_INITIALIZATION_##type( \ 104 data, len, (clss)->class_loader(), thread_type); \ 105 } 106 107#define DTRACE_CLASSINIT_PROBE_WAIT(type, clss, thread_type, wait) \ 108 { \ 109 char* data = NULL; \ 110 int len = 0; \ 111 Symbol* name = (clss)->name(); \ 112 if (name != NULL) { \ 113 data = (char*)name->bytes(); \ 114 len = name->utf8_length(); \ 115 } \ 116 HOTSPOT_CLASS_INITIALIZATION_##type( \ 117 data, len, (clss)->class_loader(), thread_type, wait); \ 118 } 119 120#else // ndef DTRACE_ENABLED 121 122#define DTRACE_CLASSINIT_PROBE(type, clss, thread_type) 123#define DTRACE_CLASSINIT_PROBE_WAIT(type, clss, thread_type, wait) 124 125#endif // ndef DTRACE_ENABLED 126 127volatile int InstanceKlass::_total_instanceKlass_count = 0; 128 129InstanceKlass* InstanceKlass::allocate_instance_klass( 130 ClassLoaderData* loader_data, 131 int vtable_len, 132 int itable_len, 133 int static_field_size, 134 int nonstatic_oop_map_size, 135 ReferenceType rt, 136 AccessFlags access_flags, 137 Symbol* name, 138 Klass* super_klass, 139 bool is_anonymous, 140 TRAPS) { 141 142 int size = InstanceKlass::size(vtable_len, itable_len, nonstatic_oop_map_size, 143 access_flags.is_interface(), is_anonymous); 144 145 // Allocation 146 InstanceKlass* ik; 147 if (rt == REF_NONE) { 148 if (name == vmSymbols::java_lang_Class()) { 149 ik = new (loader_data, size, THREAD) InstanceMirrorKlass( 150 vtable_len, itable_len, static_field_size, nonstatic_oop_map_size, rt, 151 access_flags, is_anonymous); 152 } else if (name == vmSymbols::java_lang_ClassLoader() || 153 (SystemDictionary::ClassLoader_klass_loaded() && 154 super_klass != NULL && 155 super_klass->is_subtype_of(SystemDictionary::ClassLoader_klass()))) { 156 ik = new (loader_data, size, THREAD) InstanceClassLoaderKlass( 157 vtable_len, itable_len, static_field_size, nonstatic_oop_map_size, rt, 158 access_flags, is_anonymous); 159 } else { 160 // normal class 161 ik = new (loader_data, size, THREAD) InstanceKlass( 162 vtable_len, itable_len, static_field_size, nonstatic_oop_map_size, rt, 163 access_flags, is_anonymous); 164 } 165 } else { 166 // reference klass 167 ik = new (loader_data, size, THREAD) InstanceRefKlass( 168 vtable_len, itable_len, static_field_size, nonstatic_oop_map_size, rt, 169 access_flags, is_anonymous); 170 } 171 172 // Check for pending exception before adding to the loader data and incrementing 173 // class count. Can get OOM here. 174 if (HAS_PENDING_EXCEPTION) { 175 return NULL; 176 } 177 178 // Add all classes to our internal class loader list here, 179 // including classes in the bootstrap (NULL) class loader. 180 loader_data->add_class(ik); 181 182 Atomic::inc(&_total_instanceKlass_count); 183 return ik; 184} 185 186 187// copy method ordering from resource area to Metaspace 188void InstanceKlass::copy_method_ordering(intArray* m, TRAPS) { 189 if (m != NULL) { 190 // allocate a new array and copy contents (memcpy?) 191 _method_ordering = MetadataFactory::new_array<int>(class_loader_data(), m->length(), CHECK); 192 for (int i = 0; i < m->length(); i++) { 193 _method_ordering->at_put(i, m->at(i)); 194 } 195 } else { 196 _method_ordering = Universe::the_empty_int_array(); 197 } 198} 199 200// create a new array of vtable_indices for default methods 201Array<int>* InstanceKlass::create_new_default_vtable_indices(int len, TRAPS) { 202 Array<int>* vtable_indices = MetadataFactory::new_array<int>(class_loader_data(), len, CHECK_NULL); 203 assert(default_vtable_indices() == NULL, "only create once"); 204 set_default_vtable_indices(vtable_indices); 205 return vtable_indices; 206} 207 208InstanceKlass::InstanceKlass(int vtable_len, 209 int itable_len, 210 int static_field_size, 211 int nonstatic_oop_map_size, 212 ReferenceType rt, 213 AccessFlags access_flags, 214 bool is_anonymous) { 215 No_Safepoint_Verifier no_safepoint; // until k becomes parsable 216 217 int iksize = InstanceKlass::size(vtable_len, itable_len, nonstatic_oop_map_size, 218 access_flags.is_interface(), is_anonymous); 219 220 set_vtable_length(vtable_len); 221 set_itable_length(itable_len); 222 set_static_field_size(static_field_size); 223 set_nonstatic_oop_map_size(nonstatic_oop_map_size); 224 set_access_flags(access_flags); 225 _misc_flags = 0; // initialize to zero 226 set_is_anonymous(is_anonymous); 227 assert(size() == iksize, "wrong size for object"); 228 229 set_array_klasses(NULL); 230 set_methods(NULL); 231 set_method_ordering(NULL); 232 set_default_methods(NULL); 233 set_default_vtable_indices(NULL); 234 set_local_interfaces(NULL); 235 set_transitive_interfaces(NULL); 236 init_implementor(); 237 set_fields(NULL, 0); 238 set_constants(NULL); 239 set_class_loader_data(NULL); 240 set_source_file_name_index(0); 241 set_source_debug_extension(NULL, 0); 242 set_array_name(NULL); 243 set_inner_classes(NULL); 244 set_static_oop_field_count(0); 245 set_nonstatic_field_size(0); 246 set_is_marked_dependent(false); 247 set_init_state(InstanceKlass::allocated); 248 set_init_thread(NULL); 249 set_reference_type(rt); 250 set_oop_map_cache(NULL); 251 set_jni_ids(NULL); 252 set_osr_nmethods_head(NULL); 253 set_breakpoints(NULL); 254 init_previous_versions(); 255 set_generic_signature_index(0); 256 release_set_methods_jmethod_ids(NULL); 257 set_annotations(NULL); 258 set_jvmti_cached_class_field_map(NULL); 259 set_initial_method_idnum(0); 260 _dependencies = NULL; 261 set_jvmti_cached_class_field_map(NULL); 262 set_cached_class_file(NULL); 263 set_initial_method_idnum(0); 264 set_minor_version(0); 265 set_major_version(0); 266 NOT_PRODUCT(_verify_count = 0;) 267 268 // initialize the non-header words to zero 269 intptr_t* p = (intptr_t*)this; 270 for (int index = InstanceKlass::header_size(); index < iksize; index++) { 271 p[index] = NULL_WORD; 272 } 273 274 // Set temporary value until parseClassFile updates it with the real instance 275 // size. 276 set_layout_helper(Klass::instance_layout_helper(0, true)); 277} 278 279 280void InstanceKlass::deallocate_methods(ClassLoaderData* loader_data, 281 Array<Method*>* methods) { 282 if (methods != NULL && methods != Universe::the_empty_method_array() && 283 !methods->is_shared()) { 284 for (int i = 0; i < methods->length(); i++) { 285 Method* method = methods->at(i); 286 if (method == NULL) continue; // maybe null if error processing 287 // Only want to delete methods that are not executing for RedefineClasses. 288 // The previous version will point to them so they're not totally dangling 289 assert (!method->on_stack(), "shouldn't be called with methods on stack"); 290 MetadataFactory::free_metadata(loader_data, method); 291 } 292 MetadataFactory::free_array<Method*>(loader_data, methods); 293 } 294} 295 296void InstanceKlass::deallocate_interfaces(ClassLoaderData* loader_data, 297 Klass* super_klass, 298 Array<Klass*>* local_interfaces, 299 Array<Klass*>* transitive_interfaces) { 300 // Only deallocate transitive interfaces if not empty, same as super class 301 // or same as local interfaces. See code in parseClassFile. 302 Array<Klass*>* ti = transitive_interfaces; 303 if (ti != Universe::the_empty_klass_array() && ti != local_interfaces) { 304 // check that the interfaces don't come from super class 305 Array<Klass*>* sti = (super_klass == NULL) ? NULL : 306 InstanceKlass::cast(super_klass)->transitive_interfaces(); 307 if (ti != sti && ti != NULL && !ti->is_shared()) { 308 MetadataFactory::free_array<Klass*>(loader_data, ti); 309 } 310 } 311 312 // local interfaces can be empty 313 if (local_interfaces != Universe::the_empty_klass_array() && 314 local_interfaces != NULL && !local_interfaces->is_shared()) { 315 MetadataFactory::free_array<Klass*>(loader_data, local_interfaces); 316 } 317} 318 319// This function deallocates the metadata and C heap pointers that the 320// InstanceKlass points to. 321void InstanceKlass::deallocate_contents(ClassLoaderData* loader_data) { 322 323 // Orphan the mirror first, CMS thinks it's still live. 324 if (java_mirror() != NULL) { 325 java_lang_Class::set_klass(java_mirror(), NULL); 326 } 327 328 // Need to take this class off the class loader data list. 329 loader_data->remove_class(this); 330 331 // The array_klass for this class is created later, after error handling. 332 // For class redefinition, we keep the original class so this scratch class 333 // doesn't have an array class. Either way, assert that there is nothing 334 // to deallocate. 335 assert(array_klasses() == NULL, "array classes shouldn't be created for this class yet"); 336 337 // Release C heap allocated data that this might point to, which includes 338 // reference counting symbol names. 339 release_C_heap_structures(); 340 341 deallocate_methods(loader_data, methods()); 342 set_methods(NULL); 343 344 if (method_ordering() != NULL && 345 method_ordering() != Universe::the_empty_int_array() && 346 !method_ordering()->is_shared()) { 347 MetadataFactory::free_array<int>(loader_data, method_ordering()); 348 } 349 set_method_ordering(NULL); 350 351 // default methods can be empty 352 if (default_methods() != NULL && 353 default_methods() != Universe::the_empty_method_array() && 354 !default_methods()->is_shared()) { 355 MetadataFactory::free_array<Method*>(loader_data, default_methods()); 356 } 357 // Do NOT deallocate the default methods, they are owned by superinterfaces. 358 set_default_methods(NULL); 359 360 // default methods vtable indices can be empty 361 if (default_vtable_indices() != NULL && 362 !default_vtable_indices()->is_shared()) { 363 MetadataFactory::free_array<int>(loader_data, default_vtable_indices()); 364 } 365 set_default_vtable_indices(NULL); 366 367 368 // This array is in Klass, but remove it with the InstanceKlass since 369 // this place would be the only caller and it can share memory with transitive 370 // interfaces. 371 if (secondary_supers() != NULL && 372 secondary_supers() != Universe::the_empty_klass_array() && 373 secondary_supers() != transitive_interfaces() && 374 !secondary_supers()->is_shared()) { 375 MetadataFactory::free_array<Klass*>(loader_data, secondary_supers()); 376 } 377 set_secondary_supers(NULL); 378 379 deallocate_interfaces(loader_data, super(), local_interfaces(), transitive_interfaces()); 380 set_transitive_interfaces(NULL); 381 set_local_interfaces(NULL); 382 383 if (fields() != NULL && !fields()->is_shared()) { 384 MetadataFactory::free_array<jushort>(loader_data, fields()); 385 } 386 set_fields(NULL, 0); 387 388 // If a method from a redefined class is using this constant pool, don't 389 // delete it, yet. The new class's previous version will point to this. 390 if (constants() != NULL) { 391 assert (!constants()->on_stack(), "shouldn't be called if anything is onstack"); 392 if (!constants()->is_shared()) { 393 MetadataFactory::free_metadata(loader_data, constants()); 394 } 395 set_constants(NULL); 396 } 397 398 if (inner_classes() != NULL && 399 inner_classes() != Universe::the_empty_short_array() && 400 !inner_classes()->is_shared()) { 401 MetadataFactory::free_array<jushort>(loader_data, inner_classes()); 402 } 403 set_inner_classes(NULL); 404 405 // We should deallocate the Annotations instance if it's not in shared spaces. 406 if (annotations() != NULL && !annotations()->is_shared()) { 407 MetadataFactory::free_metadata(loader_data, annotations()); 408 } 409 set_annotations(NULL); 410} 411 412bool InstanceKlass::should_be_initialized() const { 413 return !is_initialized(); 414} 415 416klassVtable* InstanceKlass::vtable() const { 417 return new klassVtable(this, start_of_vtable(), vtable_length() / vtableEntry::size()); 418} 419 420klassItable* InstanceKlass::itable() const { 421 return new klassItable(instanceKlassHandle(this)); 422} 423 424void InstanceKlass::eager_initialize(Thread *thread) { 425 if (!EagerInitialization) return; 426 427 if (this->is_not_initialized()) { 428 // abort if the the class has a class initializer 429 if (this->class_initializer() != NULL) return; 430 431 // abort if it is java.lang.Object (initialization is handled in genesis) 432 Klass* super = this->super(); 433 if (super == NULL) return; 434 435 // abort if the super class should be initialized 436 if (!InstanceKlass::cast(super)->is_initialized()) return; 437 438 // call body to expose the this pointer 439 instanceKlassHandle this_k(thread, this); 440 eager_initialize_impl(this_k); 441 } 442} 443 444// JVMTI spec thinks there are signers and protection domain in the 445// instanceKlass. These accessors pretend these fields are there. 446// The hprof specification also thinks these fields are in InstanceKlass. 447oop InstanceKlass::protection_domain() const { 448 // return the protection_domain from the mirror 449 return java_lang_Class::protection_domain(java_mirror()); 450} 451 452// To remove these from requires an incompatible change and CCC request. 453objArrayOop InstanceKlass::signers() const { 454 // return the signers from the mirror 455 return java_lang_Class::signers(java_mirror()); 456} 457 458oop InstanceKlass::init_lock() const { 459 // return the init lock from the mirror 460 oop lock = java_lang_Class::init_lock(java_mirror()); 461 assert((oop)lock != NULL || !is_not_initialized(), // initialized or in_error state 462 "only fully initialized state can have a null lock"); 463 return lock; 464} 465 466// Set the initialization lock to null so the object can be GC'ed. Any racing 467// threads to get this lock will see a null lock and will not lock. 468// That's okay because they all check for initialized state after getting 469// the lock and return. 470void InstanceKlass::fence_and_clear_init_lock() { 471 // make sure previous stores are all done, notably the init_state. 472 OrderAccess::storestore(); 473 java_lang_Class::set_init_lock(java_mirror(), NULL); 474 assert(!is_not_initialized(), "class must be initialized now"); 475} 476 477void InstanceKlass::eager_initialize_impl(instanceKlassHandle this_k) { 478 EXCEPTION_MARK; 479 oop init_lock = this_k->init_lock(); 480 ObjectLocker ol(init_lock, THREAD, init_lock != NULL); 481 482 // abort if someone beat us to the initialization 483 if (!this_k->is_not_initialized()) return; // note: not equivalent to is_initialized() 484 485 ClassState old_state = this_k->init_state(); 486 link_class_impl(this_k, true, THREAD); 487 if (HAS_PENDING_EXCEPTION) { 488 CLEAR_PENDING_EXCEPTION; 489 // Abort if linking the class throws an exception. 490 491 // Use a test to avoid redundantly resetting the state if there's 492 // no change. Set_init_state() asserts that state changes make 493 // progress, whereas here we might just be spinning in place. 494 if( old_state != this_k->_init_state ) 495 this_k->set_init_state (old_state); 496 } else { 497 // linking successfull, mark class as initialized 498 this_k->set_init_state (fully_initialized); 499 this_k->fence_and_clear_init_lock(); 500 // trace 501 if (TraceClassInitialization) { 502 ResourceMark rm(THREAD); 503 tty->print_cr("[Initialized %s without side effects]", this_k->external_name()); 504 } 505 } 506} 507 508 509// See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization 510// process. The step comments refers to the procedure described in that section. 511// Note: implementation moved to static method to expose the this pointer. 512void InstanceKlass::initialize(TRAPS) { 513 if (this->should_be_initialized()) { 514 HandleMark hm(THREAD); 515 instanceKlassHandle this_k(THREAD, this); 516 initialize_impl(this_k, CHECK); 517 // Note: at this point the class may be initialized 518 // OR it may be in the state of being initialized 519 // in case of recursive initialization! 520 } else { 521 assert(is_initialized(), "sanity check"); 522 } 523} 524 525 526bool InstanceKlass::verify_code( 527 instanceKlassHandle this_k, bool throw_verifyerror, TRAPS) { 528 // 1) Verify the bytecodes 529 Verifier::Mode mode = 530 throw_verifyerror ? Verifier::ThrowException : Verifier::NoException; 531 return Verifier::verify(this_k, mode, this_k->should_verify_class(), CHECK_false); 532} 533 534 535// Used exclusively by the shared spaces dump mechanism to prevent 536// classes mapped into the shared regions in new VMs from appearing linked. 537 538void InstanceKlass::unlink_class() { 539 assert(is_linked(), "must be linked"); 540 _init_state = loaded; 541} 542 543void InstanceKlass::link_class(TRAPS) { 544 assert(is_loaded(), "must be loaded"); 545 if (!is_linked()) { 546 HandleMark hm(THREAD); 547 instanceKlassHandle this_k(THREAD, this); 548 link_class_impl(this_k, true, CHECK); 549 } 550} 551 552// Called to verify that a class can link during initialization, without 553// throwing a VerifyError. 554bool InstanceKlass::link_class_or_fail(TRAPS) { 555 assert(is_loaded(), "must be loaded"); 556 if (!is_linked()) { 557 HandleMark hm(THREAD); 558 instanceKlassHandle this_k(THREAD, this); 559 link_class_impl(this_k, false, CHECK_false); 560 } 561 return is_linked(); 562} 563 564bool InstanceKlass::link_class_impl( 565 instanceKlassHandle this_k, bool throw_verifyerror, TRAPS) { 566 // check for error state 567 if (this_k->is_in_error_state()) { 568 ResourceMark rm(THREAD); 569 THROW_MSG_(vmSymbols::java_lang_NoClassDefFoundError(), 570 this_k->external_name(), false); 571 } 572 // return if already verified 573 if (this_k->is_linked()) { 574 return true; 575 } 576 577 // Timing 578 // timer handles recursion 579 assert(THREAD->is_Java_thread(), "non-JavaThread in link_class_impl"); 580 JavaThread* jt = (JavaThread*)THREAD; 581 582 // link super class before linking this class 583 instanceKlassHandle super(THREAD, this_k->super()); 584 if (super.not_null()) { 585 if (super->is_interface()) { // check if super class is an interface 586 ResourceMark rm(THREAD); 587 Exceptions::fthrow( 588 THREAD_AND_LOCATION, 589 vmSymbols::java_lang_IncompatibleClassChangeError(), 590 "class %s has interface %s as super class", 591 this_k->external_name(), 592 super->external_name() 593 ); 594 return false; 595 } 596 597 link_class_impl(super, throw_verifyerror, CHECK_false); 598 } 599 600 // link all interfaces implemented by this class before linking this class 601 Array<Klass*>* interfaces = this_k->local_interfaces(); 602 int num_interfaces = interfaces->length(); 603 for (int index = 0; index < num_interfaces; index++) { 604 HandleMark hm(THREAD); 605 instanceKlassHandle ih(THREAD, interfaces->at(index)); 606 link_class_impl(ih, throw_verifyerror, CHECK_false); 607 } 608 609 // in case the class is linked in the process of linking its superclasses 610 if (this_k->is_linked()) { 611 return true; 612 } 613 614 // trace only the link time for this klass that includes 615 // the verification time 616 PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(), 617 ClassLoader::perf_class_link_selftime(), 618 ClassLoader::perf_classes_linked(), 619 jt->get_thread_stat()->perf_recursion_counts_addr(), 620 jt->get_thread_stat()->perf_timers_addr(), 621 PerfClassTraceTime::CLASS_LINK); 622 623 // verification & rewriting 624 { 625 oop init_lock = this_k->init_lock(); 626 ObjectLocker ol(init_lock, THREAD, init_lock != NULL); 627 // rewritten will have been set if loader constraint error found 628 // on an earlier link attempt 629 // don't verify or rewrite if already rewritten 630 631 if (!this_k->is_linked()) { 632 if (!this_k->is_rewritten()) { 633 { 634 // Timer includes any side effects of class verification (resolution, 635 // etc), but not recursive entry into verify_code(). 636 PerfClassTraceTime timer(ClassLoader::perf_class_verify_time(), 637 ClassLoader::perf_class_verify_selftime(), 638 ClassLoader::perf_classes_verified(), 639 jt->get_thread_stat()->perf_recursion_counts_addr(), 640 jt->get_thread_stat()->perf_timers_addr(), 641 PerfClassTraceTime::CLASS_VERIFY); 642 bool verify_ok = verify_code(this_k, throw_verifyerror, THREAD); 643 if (!verify_ok) { 644 return false; 645 } 646 } 647 648 // Just in case a side-effect of verify linked this class already 649 // (which can sometimes happen since the verifier loads classes 650 // using custom class loaders, which are free to initialize things) 651 if (this_k->is_linked()) { 652 return true; 653 } 654 655 // also sets rewritten 656 this_k->rewrite_class(CHECK_false); 657 } 658 659 // relocate jsrs and link methods after they are all rewritten 660 this_k->link_methods(CHECK_false); 661 662 // Initialize the vtable and interface table after 663 // methods have been rewritten since rewrite may 664 // fabricate new Method*s. 665 // also does loader constraint checking 666 if (!this_k()->is_shared()) { 667 ResourceMark rm(THREAD); 668 this_k->vtable()->initialize_vtable(true, CHECK_false); 669 this_k->itable()->initialize_itable(true, CHECK_false); 670 } 671#ifdef ASSERT 672 else { 673 ResourceMark rm(THREAD); 674 this_k->vtable()->verify(tty, true); 675 // In case itable verification is ever added. 676 // this_k->itable()->verify(tty, true); 677 } 678#endif 679 this_k->set_init_state(linked); 680 if (JvmtiExport::should_post_class_prepare()) { 681 Thread *thread = THREAD; 682 assert(thread->is_Java_thread(), "thread->is_Java_thread()"); 683 JvmtiExport::post_class_prepare((JavaThread *) thread, this_k()); 684 } 685 } 686 } 687 return true; 688} 689 690 691// Rewrite the byte codes of all of the methods of a class. 692// The rewriter must be called exactly once. Rewriting must happen after 693// verification but before the first method of the class is executed. 694void InstanceKlass::rewrite_class(TRAPS) { 695 assert(is_loaded(), "must be loaded"); 696 instanceKlassHandle this_k(THREAD, this); 697 if (this_k->is_rewritten()) { 698 assert(this_k()->is_shared(), "rewriting an unshared class?"); 699 return; 700 } 701 Rewriter::rewrite(this_k, CHECK); 702 this_k->set_rewritten(); 703} 704 705// Now relocate and link method entry points after class is rewritten. 706// This is outside is_rewritten flag. In case of an exception, it can be 707// executed more than once. 708void InstanceKlass::link_methods(TRAPS) { 709 int len = methods()->length(); 710 for (int i = len-1; i >= 0; i--) { 711 methodHandle m(THREAD, methods()->at(i)); 712 713 // Set up method entry points for compiler and interpreter . 714 m->link_method(m, CHECK); 715 716 // This is for JVMTI and unrelated to relocator but the last thing we do 717#ifdef ASSERT 718 if (StressMethodComparator) { 719 ResourceMark rm(THREAD); 720 static int nmc = 0; 721 for (int j = i; j >= 0 && j >= i-4; j--) { 722 if ((++nmc % 1000) == 0) tty->print_cr("Have run MethodComparator %d times...", nmc); 723 bool z = MethodComparator::methods_EMCP(m(), 724 methods()->at(j)); 725 if (j == i && !z) { 726 tty->print("MethodComparator FAIL: "); m->print(); m->print_codes(); 727 assert(z, "method must compare equal to itself"); 728 } 729 } 730 } 731#endif //ASSERT 732 } 733} 734 735 736void InstanceKlass::initialize_impl(instanceKlassHandle this_k, TRAPS) { 737 // Make sure klass is linked (verified) before initialization 738 // A class could already be verified, since it has been reflected upon. 739 this_k->link_class(CHECK); 740 741 DTRACE_CLASSINIT_PROBE(required, InstanceKlass::cast(this_k()), -1); 742 743 bool wait = false; 744 745 // refer to the JVM book page 47 for description of steps 746 // Step 1 747 { 748 oop init_lock = this_k->init_lock(); 749 ObjectLocker ol(init_lock, THREAD, init_lock != NULL); 750 751 Thread *self = THREAD; // it's passed the current thread 752 753 // Step 2 754 // If we were to use wait() instead of waitInterruptibly() then 755 // we might end up throwing IE from link/symbol resolution sites 756 // that aren't expected to throw. This would wreak havoc. See 6320309. 757 while(this_k->is_being_initialized() && !this_k->is_reentrant_initialization(self)) { 758 wait = true; 759 ol.waitUninterruptibly(CHECK); 760 } 761 762 // Step 3 763 if (this_k->is_being_initialized() && this_k->is_reentrant_initialization(self)) { 764 DTRACE_CLASSINIT_PROBE_WAIT(recursive, InstanceKlass::cast(this_k()), -1,wait); 765 return; 766 } 767 768 // Step 4 769 if (this_k->is_initialized()) { 770 DTRACE_CLASSINIT_PROBE_WAIT(concurrent, InstanceKlass::cast(this_k()), -1,wait); 771 return; 772 } 773 774 // Step 5 775 if (this_k->is_in_error_state()) { 776 DTRACE_CLASSINIT_PROBE_WAIT(erroneous, InstanceKlass::cast(this_k()), -1,wait); 777 ResourceMark rm(THREAD); 778 const char* desc = "Could not initialize class "; 779 const char* className = this_k->external_name(); 780 size_t msglen = strlen(desc) + strlen(className) + 1; 781 char* message = NEW_RESOURCE_ARRAY(char, msglen); 782 if (NULL == message) { 783 // Out of memory: can't create detailed error message 784 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), className); 785 } else { 786 jio_snprintf(message, msglen, "%s%s", desc, className); 787 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), message); 788 } 789 } 790 791 // Step 6 792 this_k->set_init_state(being_initialized); 793 this_k->set_init_thread(self); 794 } 795 796 // Step 7 797 Klass* super_klass = this_k->super(); 798 if (super_klass != NULL && !this_k->is_interface() && super_klass->should_be_initialized()) { 799 super_klass->initialize(THREAD); 800 801 if (HAS_PENDING_EXCEPTION) { 802 Handle e(THREAD, PENDING_EXCEPTION); 803 CLEAR_PENDING_EXCEPTION; 804 { 805 EXCEPTION_MARK; 806 this_k->set_initialization_state_and_notify(initialization_error, THREAD); // Locks object, set state, and notify all waiting threads 807 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, superclass initialization error is thrown below 808 } 809 DTRACE_CLASSINIT_PROBE_WAIT(super__failed, InstanceKlass::cast(this_k()), -1,wait); 810 THROW_OOP(e()); 811 } 812 } 813 814 if (this_k->has_default_methods()) { 815 // Step 7.5: initialize any interfaces which have default methods 816 for (int i = 0; i < this_k->local_interfaces()->length(); ++i) { 817 Klass* iface = this_k->local_interfaces()->at(i); 818 InstanceKlass* ik = InstanceKlass::cast(iface); 819 if (ik->has_default_methods() && ik->should_be_initialized()) { 820 ik->initialize(THREAD); 821 822 if (HAS_PENDING_EXCEPTION) { 823 Handle e(THREAD, PENDING_EXCEPTION); 824 CLEAR_PENDING_EXCEPTION; 825 { 826 EXCEPTION_MARK; 827 // Locks object, set state, and notify all waiting threads 828 this_k->set_initialization_state_and_notify( 829 initialization_error, THREAD); 830 831 // ignore any exception thrown, superclass initialization error is 832 // thrown below 833 CLEAR_PENDING_EXCEPTION; 834 } 835 DTRACE_CLASSINIT_PROBE_WAIT( 836 super__failed, InstanceKlass::cast(this_k()), -1, wait); 837 THROW_OOP(e()); 838 } 839 } 840 } 841 } 842 843 // Step 8 844 { 845 assert(THREAD->is_Java_thread(), "non-JavaThread in initialize_impl"); 846 JavaThread* jt = (JavaThread*)THREAD; 847 DTRACE_CLASSINIT_PROBE_WAIT(clinit, InstanceKlass::cast(this_k()), -1,wait); 848 // Timer includes any side effects of class initialization (resolution, 849 // etc), but not recursive entry into call_class_initializer(). 850 PerfClassTraceTime timer(ClassLoader::perf_class_init_time(), 851 ClassLoader::perf_class_init_selftime(), 852 ClassLoader::perf_classes_inited(), 853 jt->get_thread_stat()->perf_recursion_counts_addr(), 854 jt->get_thread_stat()->perf_timers_addr(), 855 PerfClassTraceTime::CLASS_CLINIT); 856 this_k->call_class_initializer(THREAD); 857 } 858 859 // Step 9 860 if (!HAS_PENDING_EXCEPTION) { 861 this_k->set_initialization_state_and_notify(fully_initialized, CHECK); 862 { ResourceMark rm(THREAD); 863 debug_only(this_k->vtable()->verify(tty, true);) 864 } 865 } 866 else { 867 // Step 10 and 11 868 Handle e(THREAD, PENDING_EXCEPTION); 869 CLEAR_PENDING_EXCEPTION; 870 // JVMTI has already reported the pending exception 871 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError 872 JvmtiExport::clear_detected_exception((JavaThread*)THREAD); 873 { 874 EXCEPTION_MARK; 875 this_k->set_initialization_state_and_notify(initialization_error, THREAD); 876 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, class initialization error is thrown below 877 // JVMTI has already reported the pending exception 878 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError 879 JvmtiExport::clear_detected_exception((JavaThread*)THREAD); 880 } 881 DTRACE_CLASSINIT_PROBE_WAIT(error, InstanceKlass::cast(this_k()), -1,wait); 882 if (e->is_a(SystemDictionary::Error_klass())) { 883 THROW_OOP(e()); 884 } else { 885 JavaCallArguments args(e); 886 THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(), 887 vmSymbols::throwable_void_signature(), 888 &args); 889 } 890 } 891 DTRACE_CLASSINIT_PROBE_WAIT(end, InstanceKlass::cast(this_k()), -1,wait); 892} 893 894 895// Note: implementation moved to static method to expose the this pointer. 896void InstanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) { 897 instanceKlassHandle kh(THREAD, this); 898 set_initialization_state_and_notify_impl(kh, state, CHECK); 899} 900 901void InstanceKlass::set_initialization_state_and_notify_impl(instanceKlassHandle this_k, ClassState state, TRAPS) { 902 oop init_lock = this_k->init_lock(); 903 ObjectLocker ol(init_lock, THREAD, init_lock != NULL); 904 this_k->set_init_state(state); 905 this_k->fence_and_clear_init_lock(); 906 ol.notify_all(CHECK); 907} 908 909// The embedded _implementor field can only record one implementor. 910// When there are more than one implementors, the _implementor field 911// is set to the interface Klass* itself. Following are the possible 912// values for the _implementor field: 913// NULL - no implementor 914// implementor Klass* - one implementor 915// self - more than one implementor 916// 917// The _implementor field only exists for interfaces. 918void InstanceKlass::add_implementor(Klass* k) { 919 assert(Compile_lock->owned_by_self(), ""); 920 assert(is_interface(), "not interface"); 921 // Filter out my subinterfaces. 922 // (Note: Interfaces are never on the subklass list.) 923 if (InstanceKlass::cast(k)->is_interface()) return; 924 925 // Filter out subclasses whose supers already implement me. 926 // (Note: CHA must walk subclasses of direct implementors 927 // in order to locate indirect implementors.) 928 Klass* sk = InstanceKlass::cast(k)->super(); 929 if (sk != NULL && InstanceKlass::cast(sk)->implements_interface(this)) 930 // We only need to check one immediate superclass, since the 931 // implements_interface query looks at transitive_interfaces. 932 // Any supers of the super have the same (or fewer) transitive_interfaces. 933 return; 934 935 Klass* ik = implementor(); 936 if (ik == NULL) { 937 set_implementor(k); 938 } else if (ik != this) { 939 // There is already an implementor. Use itself as an indicator of 940 // more than one implementors. 941 set_implementor(this); 942 } 943 944 // The implementor also implements the transitive_interfaces 945 for (int index = 0; index < local_interfaces()->length(); index++) { 946 InstanceKlass::cast(local_interfaces()->at(index))->add_implementor(k); 947 } 948} 949 950void InstanceKlass::init_implementor() { 951 if (is_interface()) { 952 set_implementor(NULL); 953 } 954} 955 956 957void InstanceKlass::process_interfaces(Thread *thread) { 958 // link this class into the implementors list of every interface it implements 959 for (int i = local_interfaces()->length() - 1; i >= 0; i--) { 960 assert(local_interfaces()->at(i)->is_klass(), "must be a klass"); 961 InstanceKlass* interf = InstanceKlass::cast(local_interfaces()->at(i)); 962 assert(interf->is_interface(), "expected interface"); 963 interf->add_implementor(this); 964 } 965} 966 967bool InstanceKlass::can_be_primary_super_slow() const { 968 if (is_interface()) 969 return false; 970 else 971 return Klass::can_be_primary_super_slow(); 972} 973 974GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots) { 975 // The secondaries are the implemented interfaces. 976 InstanceKlass* ik = InstanceKlass::cast(this); 977 Array<Klass*>* interfaces = ik->transitive_interfaces(); 978 int num_secondaries = num_extra_slots + interfaces->length(); 979 if (num_secondaries == 0) { 980 // Must share this for correct bootstrapping! 981 set_secondary_supers(Universe::the_empty_klass_array()); 982 return NULL; 983 } else if (num_extra_slots == 0) { 984 // The secondary super list is exactly the same as the transitive interfaces. 985 // Redefine classes has to be careful not to delete this! 986 set_secondary_supers(interfaces); 987 return NULL; 988 } else { 989 // Copy transitive interfaces to a temporary growable array to be constructed 990 // into the secondary super list with extra slots. 991 GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length()); 992 for (int i = 0; i < interfaces->length(); i++) { 993 secondaries->push(interfaces->at(i)); 994 } 995 return secondaries; 996 } 997} 998 999bool InstanceKlass::compute_is_subtype_of(Klass* k) { 1000 if (k->is_interface()) { 1001 return implements_interface(k); 1002 } else { 1003 return Klass::compute_is_subtype_of(k); 1004 } 1005} 1006 1007bool InstanceKlass::implements_interface(Klass* k) const { 1008 if (this == k) return true; 1009 assert(k->is_interface(), "should be an interface class"); 1010 for (int i = 0; i < transitive_interfaces()->length(); i++) { 1011 if (transitive_interfaces()->at(i) == k) { 1012 return true; 1013 } 1014 } 1015 return false; 1016} 1017 1018bool InstanceKlass::is_same_or_direct_interface(Klass *k) const { 1019 // Verify direct super interface 1020 if (this == k) return true; 1021 assert(k->is_interface(), "should be an interface class"); 1022 for (int i = 0; i < local_interfaces()->length(); i++) { 1023 if (local_interfaces()->at(i) == k) { 1024 return true; 1025 } 1026 } 1027 return false; 1028} 1029 1030objArrayOop InstanceKlass::allocate_objArray(int n, int length, TRAPS) { 1031 if (length < 0) THROW_0(vmSymbols::java_lang_NegativeArraySizeException()); 1032 if (length > arrayOopDesc::max_array_length(T_OBJECT)) { 1033 report_java_out_of_memory("Requested array size exceeds VM limit"); 1034 JvmtiExport::post_array_size_exhausted(); 1035 THROW_OOP_0(Universe::out_of_memory_error_array_size()); 1036 } 1037 int size = objArrayOopDesc::object_size(length); 1038 Klass* ak = array_klass(n, CHECK_NULL); 1039 KlassHandle h_ak (THREAD, ak); 1040 objArrayOop o = 1041 (objArrayOop)CollectedHeap::array_allocate(h_ak, size, length, CHECK_NULL); 1042 return o; 1043} 1044 1045instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) { 1046 if (TraceFinalizerRegistration) { 1047 tty->print("Registered "); 1048 i->print_value_on(tty); 1049 tty->print_cr(" (" INTPTR_FORMAT ") as finalizable", (address)i); 1050 } 1051 instanceHandle h_i(THREAD, i); 1052 // Pass the handle as argument, JavaCalls::call expects oop as jobjects 1053 JavaValue result(T_VOID); 1054 JavaCallArguments args(h_i); 1055 methodHandle mh (THREAD, Universe::finalizer_register_method()); 1056 JavaCalls::call(&result, mh, &args, CHECK_NULL); 1057 return h_i(); 1058} 1059 1060instanceOop InstanceKlass::allocate_instance(TRAPS) { 1061 bool has_finalizer_flag = has_finalizer(); // Query before possible GC 1062 int size = size_helper(); // Query before forming handle. 1063 1064 KlassHandle h_k(THREAD, this); 1065 1066 instanceOop i; 1067 1068 i = (instanceOop)CollectedHeap::obj_allocate(h_k, size, CHECK_NULL); 1069 if (has_finalizer_flag && !RegisterFinalizersAtInit) { 1070 i = register_finalizer(i, CHECK_NULL); 1071 } 1072 return i; 1073} 1074 1075void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) { 1076 if (is_interface() || is_abstract()) { 1077 ResourceMark rm(THREAD); 1078 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError() 1079 : vmSymbols::java_lang_InstantiationException(), external_name()); 1080 } 1081 if (this == SystemDictionary::Class_klass()) { 1082 ResourceMark rm(THREAD); 1083 THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError() 1084 : vmSymbols::java_lang_IllegalAccessException(), external_name()); 1085 } 1086} 1087 1088Klass* InstanceKlass::array_klass_impl(bool or_null, int n, TRAPS) { 1089 instanceKlassHandle this_k(THREAD, this); 1090 return array_klass_impl(this_k, or_null, n, THREAD); 1091} 1092 1093Klass* InstanceKlass::array_klass_impl(instanceKlassHandle this_k, bool or_null, int n, TRAPS) { 1094 if (this_k->array_klasses() == NULL) { 1095 if (or_null) return NULL; 1096 1097 ResourceMark rm; 1098 JavaThread *jt = (JavaThread *)THREAD; 1099 { 1100 // Atomic creation of array_klasses 1101 MutexLocker mc(Compile_lock, THREAD); // for vtables 1102 MutexLocker ma(MultiArray_lock, THREAD); 1103 1104 // Check if update has already taken place 1105 if (this_k->array_klasses() == NULL) { 1106 Klass* k = ObjArrayKlass::allocate_objArray_klass(this_k->class_loader_data(), 1, this_k, CHECK_NULL); 1107 this_k->set_array_klasses(k); 1108 } 1109 } 1110 } 1111 // _this will always be set at this point 1112 ObjArrayKlass* oak = (ObjArrayKlass*)this_k->array_klasses(); 1113 if (or_null) { 1114 return oak->array_klass_or_null(n); 1115 } 1116 return oak->array_klass(n, CHECK_NULL); 1117} 1118 1119Klass* InstanceKlass::array_klass_impl(bool or_null, TRAPS) { 1120 return array_klass_impl(or_null, 1, THREAD); 1121} 1122 1123void InstanceKlass::call_class_initializer(TRAPS) { 1124 instanceKlassHandle ik (THREAD, this); 1125 call_class_initializer_impl(ik, THREAD); 1126} 1127 1128static int call_class_initializer_impl_counter = 0; // for debugging 1129 1130Method* InstanceKlass::class_initializer() { 1131 Method* clinit = find_method( 1132 vmSymbols::class_initializer_name(), vmSymbols::void_method_signature()); 1133 if (clinit != NULL && clinit->has_valid_initializer_flags()) { 1134 return clinit; 1135 } 1136 return NULL; 1137} 1138 1139void InstanceKlass::call_class_initializer_impl(instanceKlassHandle this_k, TRAPS) { 1140 if (ReplayCompiles && 1141 (ReplaySuppressInitializers == 1 || 1142 ReplaySuppressInitializers >= 2 && this_k->class_loader() != NULL)) { 1143 // Hide the existence of the initializer for the purpose of replaying the compile 1144 return; 1145 } 1146 1147 methodHandle h_method(THREAD, this_k->class_initializer()); 1148 assert(!this_k->is_initialized(), "we cannot initialize twice"); 1149 if (TraceClassInitialization) { 1150 tty->print("%d Initializing ", call_class_initializer_impl_counter++); 1151 this_k->name()->print_value(); 1152 tty->print_cr("%s (" INTPTR_FORMAT ")", h_method() == NULL ? "(no method)" : "", (address)this_k()); 1153 } 1154 if (h_method() != NULL) { 1155 JavaCallArguments args; // No arguments 1156 JavaValue result(T_VOID); 1157 JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args) 1158 } 1159} 1160 1161 1162void InstanceKlass::mask_for(methodHandle method, int bci, 1163 InterpreterOopMap* entry_for) { 1164 // Dirty read, then double-check under a lock. 1165 if (_oop_map_cache == NULL) { 1166 // Otherwise, allocate a new one. 1167 MutexLocker x(OopMapCacheAlloc_lock); 1168 // First time use. Allocate a cache in C heap 1169 if (_oop_map_cache == NULL) { 1170 // Release stores from OopMapCache constructor before assignment 1171 // to _oop_map_cache. C++ compilers on ppc do not emit the 1172 // required memory barrier only because of the volatile 1173 // qualifier of _oop_map_cache. 1174 OrderAccess::release_store_ptr(&_oop_map_cache, new OopMapCache()); 1175 } 1176 } 1177 // _oop_map_cache is constant after init; lookup below does is own locking. 1178 _oop_map_cache->lookup(method, bci, entry_for); 1179} 1180 1181 1182bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const { 1183 for (JavaFieldStream fs(this); !fs.done(); fs.next()) { 1184 Symbol* f_name = fs.name(); 1185 Symbol* f_sig = fs.signature(); 1186 if (f_name == name && f_sig == sig) { 1187 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index()); 1188 return true; 1189 } 1190 } 1191 return false; 1192} 1193 1194 1195Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const { 1196 const int n = local_interfaces()->length(); 1197 for (int i = 0; i < n; i++) { 1198 Klass* intf1 = local_interfaces()->at(i); 1199 assert(intf1->is_interface(), "just checking type"); 1200 // search for field in current interface 1201 if (InstanceKlass::cast(intf1)->find_local_field(name, sig, fd)) { 1202 assert(fd->is_static(), "interface field must be static"); 1203 return intf1; 1204 } 1205 // search for field in direct superinterfaces 1206 Klass* intf2 = InstanceKlass::cast(intf1)->find_interface_field(name, sig, fd); 1207 if (intf2 != NULL) return intf2; 1208 } 1209 // otherwise field lookup fails 1210 return NULL; 1211} 1212 1213 1214Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const { 1215 // search order according to newest JVM spec (5.4.3.2, p.167). 1216 // 1) search for field in current klass 1217 if (find_local_field(name, sig, fd)) { 1218 return const_cast<InstanceKlass*>(this); 1219 } 1220 // 2) search for field recursively in direct superinterfaces 1221 { Klass* intf = find_interface_field(name, sig, fd); 1222 if (intf != NULL) return intf; 1223 } 1224 // 3) apply field lookup recursively if superclass exists 1225 { Klass* supr = super(); 1226 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, fd); 1227 } 1228 // 4) otherwise field lookup fails 1229 return NULL; 1230} 1231 1232 1233Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const { 1234 // search order according to newest JVM spec (5.4.3.2, p.167). 1235 // 1) search for field in current klass 1236 if (find_local_field(name, sig, fd)) { 1237 if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this); 1238 } 1239 // 2) search for field recursively in direct superinterfaces 1240 if (is_static) { 1241 Klass* intf = find_interface_field(name, sig, fd); 1242 if (intf != NULL) return intf; 1243 } 1244 // 3) apply field lookup recursively if superclass exists 1245 { Klass* supr = super(); 1246 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, is_static, fd); 1247 } 1248 // 4) otherwise field lookup fails 1249 return NULL; 1250} 1251 1252 1253bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const { 1254 for (JavaFieldStream fs(this); !fs.done(); fs.next()) { 1255 if (fs.offset() == offset) { 1256 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index()); 1257 if (fd->is_static() == is_static) return true; 1258 } 1259 } 1260 return false; 1261} 1262 1263 1264bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const { 1265 Klass* klass = const_cast<InstanceKlass*>(this); 1266 while (klass != NULL) { 1267 if (InstanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) { 1268 return true; 1269 } 1270 klass = klass->super(); 1271 } 1272 return false; 1273} 1274 1275 1276void InstanceKlass::methods_do(void f(Method* method)) { 1277 // Methods aren't stable until they are loaded. This can be read outside 1278 // a lock through the ClassLoaderData for profiling 1279 if (!is_loaded()) { 1280 return; 1281 } 1282 1283 int len = methods()->length(); 1284 for (int index = 0; index < len; index++) { 1285 Method* m = methods()->at(index); 1286 assert(m->is_method(), "must be method"); 1287 f(m); 1288 } 1289} 1290 1291 1292void InstanceKlass::do_local_static_fields(FieldClosure* cl) { 1293 for (JavaFieldStream fs(this); !fs.done(); fs.next()) { 1294 if (fs.access_flags().is_static()) { 1295 fieldDescriptor& fd = fs.field_descriptor(); 1296 cl->do_field(&fd); 1297 } 1298 } 1299} 1300 1301 1302void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle mirror, TRAPS) { 1303 instanceKlassHandle h_this(THREAD, this); 1304 do_local_static_fields_impl(h_this, f, mirror, CHECK); 1305} 1306 1307 1308void InstanceKlass::do_local_static_fields_impl(instanceKlassHandle this_k, 1309 void f(fieldDescriptor* fd, Handle, TRAPS), Handle mirror, TRAPS) { 1310 for (JavaFieldStream fs(this_k()); !fs.done(); fs.next()) { 1311 if (fs.access_flags().is_static()) { 1312 fieldDescriptor& fd = fs.field_descriptor(); 1313 f(&fd, mirror, CHECK); 1314 } 1315 } 1316} 1317 1318 1319static int compare_fields_by_offset(int* a, int* b) { 1320 return a[0] - b[0]; 1321} 1322 1323void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) { 1324 InstanceKlass* super = superklass(); 1325 if (super != NULL) { 1326 super->do_nonstatic_fields(cl); 1327 } 1328 fieldDescriptor fd; 1329 int length = java_fields_count(); 1330 // In DebugInfo nonstatic fields are sorted by offset. 1331 int* fields_sorted = NEW_C_HEAP_ARRAY(int, 2*(length+1), mtClass); 1332 int j = 0; 1333 for (int i = 0; i < length; i += 1) { 1334 fd.reinitialize(this, i); 1335 if (!fd.is_static()) { 1336 fields_sorted[j + 0] = fd.offset(); 1337 fields_sorted[j + 1] = i; 1338 j += 2; 1339 } 1340 } 1341 if (j > 0) { 1342 length = j; 1343 // _sort_Fn is defined in growableArray.hpp. 1344 qsort(fields_sorted, length/2, 2*sizeof(int), (_sort_Fn)compare_fields_by_offset); 1345 for (int i = 0; i < length; i += 2) { 1346 fd.reinitialize(this, fields_sorted[i + 1]); 1347 assert(!fd.is_static() && fd.offset() == fields_sorted[i], "only nonstatic fields"); 1348 cl->do_field(&fd); 1349 } 1350 } 1351 FREE_C_HEAP_ARRAY(int, fields_sorted, mtClass); 1352} 1353 1354 1355void InstanceKlass::array_klasses_do(void f(Klass* k, TRAPS), TRAPS) { 1356 if (array_klasses() != NULL) 1357 ArrayKlass::cast(array_klasses())->array_klasses_do(f, THREAD); 1358} 1359 1360void InstanceKlass::array_klasses_do(void f(Klass* k)) { 1361 if (array_klasses() != NULL) 1362 ArrayKlass::cast(array_klasses())->array_klasses_do(f); 1363} 1364 1365#ifdef ASSERT 1366static int linear_search(Array<Method*>* methods, Symbol* name, Symbol* signature) { 1367 int len = methods->length(); 1368 for (int index = 0; index < len; index++) { 1369 Method* m = methods->at(index); 1370 assert(m->is_method(), "must be method"); 1371 if (m->signature() == signature && m->name() == name) { 1372 return index; 1373 } 1374 } 1375 return -1; 1376} 1377#endif 1378 1379static int binary_search(Array<Method*>* methods, Symbol* name) { 1380 int len = methods->length(); 1381 // methods are sorted, so do binary search 1382 int l = 0; 1383 int h = len - 1; 1384 while (l <= h) { 1385 int mid = (l + h) >> 1; 1386 Method* m = methods->at(mid); 1387 assert(m->is_method(), "must be method"); 1388 int res = m->name()->fast_compare(name); 1389 if (res == 0) { 1390 return mid; 1391 } else if (res < 0) { 1392 l = mid + 1; 1393 } else { 1394 h = mid - 1; 1395 } 1396 } 1397 return -1; 1398} 1399 1400// find_method looks up the name/signature in the local methods array 1401Method* InstanceKlass::find_method(Symbol* name, Symbol* signature) const { 1402 return find_method_impl(name, signature, false); 1403} 1404 1405Method* InstanceKlass::find_method_impl(Symbol* name, Symbol* signature, bool skipping_overpass) const { 1406 return InstanceKlass::find_method_impl(methods(), name, signature, skipping_overpass); 1407} 1408 1409// find_instance_method looks up the name/signature in the local methods array 1410// and skips over static methods 1411Method* InstanceKlass::find_instance_method( 1412 Array<Method*>* methods, Symbol* name, Symbol* signature) { 1413 Method* meth = InstanceKlass::find_method(methods, name, signature); 1414 if (meth != NULL && meth->is_static()) { 1415 meth = NULL; 1416 } 1417 return meth; 1418} 1419 1420// find_method looks up the name/signature in the local methods array 1421Method* InstanceKlass::find_method( 1422 Array<Method*>* methods, Symbol* name, Symbol* signature) { 1423 return InstanceKlass::find_method_impl(methods, name, signature, false); 1424} 1425 1426Method* InstanceKlass::find_method_impl( 1427 Array<Method*>* methods, Symbol* name, Symbol* signature, bool skipping_overpass) { 1428 int hit = find_method_index(methods, name, signature, skipping_overpass); 1429 return hit >= 0 ? methods->at(hit): NULL; 1430} 1431 1432// Used directly for default_methods to find the index into the 1433// default_vtable_indices, and indirectly by find_method 1434// find_method_index looks in the local methods array to return the index 1435// of the matching name/signature. If, overpass methods are being ignored, 1436// the search continues to find a potential non-overpass match. This capability 1437// is important during method resolution to prefer a static method, for example, 1438// over an overpass method. 1439int InstanceKlass::find_method_index( 1440 Array<Method*>* methods, Symbol* name, Symbol* signature, bool skipping_overpass) { 1441 int hit = binary_search(methods, name); 1442 if (hit != -1) { 1443 Method* m = methods->at(hit); 1444 // Do linear search to find matching signature. First, quick check 1445 // for common case, ignoring overpasses if requested. 1446 if ((m->signature() == signature) && (!skipping_overpass || !m->is_overpass())) return hit; 1447 1448 // search downwards through overloaded methods 1449 int i; 1450 for (i = hit - 1; i >= 0; --i) { 1451 Method* m = methods->at(i); 1452 assert(m->is_method(), "must be method"); 1453 if (m->name() != name) break; 1454 if ((m->signature() == signature) && (!skipping_overpass || !m->is_overpass())) return i; 1455 } 1456 // search upwards 1457 for (i = hit + 1; i < methods->length(); ++i) { 1458 Method* m = methods->at(i); 1459 assert(m->is_method(), "must be method"); 1460 if (m->name() != name) break; 1461 if ((m->signature() == signature) && (!skipping_overpass || !m->is_overpass())) return i; 1462 } 1463 // not found 1464#ifdef ASSERT 1465 int index = skipping_overpass ? -1 : linear_search(methods, name, signature); 1466 assert(index == -1, err_msg("binary search should have found entry %d", index)); 1467#endif 1468 } 1469 return -1; 1470} 1471int InstanceKlass::find_method_by_name(Symbol* name, int* end) { 1472 return find_method_by_name(methods(), name, end); 1473} 1474 1475int InstanceKlass::find_method_by_name( 1476 Array<Method*>* methods, Symbol* name, int* end_ptr) { 1477 assert(end_ptr != NULL, "just checking"); 1478 int start = binary_search(methods, name); 1479 int end = start + 1; 1480 if (start != -1) { 1481 while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start; 1482 while (end < methods->length() && (methods->at(end))->name() == name) ++end; 1483 *end_ptr = end; 1484 return start; 1485 } 1486 return -1; 1487} 1488 1489// uncached_lookup_method searches both the local class methods array and all 1490// superclasses methods arrays, skipping any overpass methods in superclasses. 1491Method* InstanceKlass::uncached_lookup_method(Symbol* name, Symbol* signature, MethodLookupMode mode) const { 1492 MethodLookupMode lookup_mode = mode; 1493 Klass* klass = const_cast<InstanceKlass*>(this); 1494 while (klass != NULL) { 1495 Method* method = InstanceKlass::cast(klass)->find_method_impl(name, signature, (lookup_mode == skip_overpass)); 1496 if (method != NULL) { 1497 return method; 1498 } 1499 klass = InstanceKlass::cast(klass)->super(); 1500 lookup_mode = skip_overpass; // Always ignore overpass methods in superclasses 1501 } 1502 return NULL; 1503} 1504 1505#ifdef ASSERT 1506// search through class hierarchy and return true if this class or 1507// one of the superclasses was redefined 1508bool InstanceKlass::has_redefined_this_or_super() const { 1509 const InstanceKlass* klass = this; 1510 while (klass != NULL) { 1511 if (klass->has_been_redefined()) { 1512 return true; 1513 } 1514 klass = InstanceKlass::cast(klass->super()); 1515 } 1516 return false; 1517} 1518#endif 1519 1520// lookup a method in the default methods list then in all transitive interfaces 1521// Do NOT return private or static methods 1522Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name, 1523 Symbol* signature) const { 1524 Method* m = NULL; 1525 if (default_methods() != NULL) { 1526 m = find_method(default_methods(), name, signature); 1527 } 1528 // Look up interfaces 1529 if (m == NULL) { 1530 m = lookup_method_in_all_interfaces(name, signature, normal); 1531 } 1532 return m; 1533} 1534 1535// lookup a method in all the interfaces that this class implements 1536// Do NOT return private or static methods, new in JDK8 which are not externally visible 1537// They should only be found in the initial InterfaceMethodRef 1538Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name, 1539 Symbol* signature, 1540 MethodLookupMode mode) const { 1541 Array<Klass*>* all_ifs = transitive_interfaces(); 1542 int num_ifs = all_ifs->length(); 1543 InstanceKlass *ik = NULL; 1544 for (int i = 0; i < num_ifs; i++) { 1545 ik = InstanceKlass::cast(all_ifs->at(i)); 1546 Method* m = ik->lookup_method(name, signature); 1547 if (m != NULL && m->is_public() && !m->is_static() && 1548 ((mode != skip_defaults) || !m->is_default_method())) { 1549 return m; 1550 } 1551 } 1552 return NULL; 1553} 1554 1555/* jni_id_for_impl for jfieldIds only */ 1556JNIid* InstanceKlass::jni_id_for_impl(instanceKlassHandle this_k, int offset) { 1557 MutexLocker ml(JfieldIdCreation_lock); 1558 // Retry lookup after we got the lock 1559 JNIid* probe = this_k->jni_ids() == NULL ? NULL : this_k->jni_ids()->find(offset); 1560 if (probe == NULL) { 1561 // Slow case, allocate new static field identifier 1562 probe = new JNIid(this_k(), offset, this_k->jni_ids()); 1563 this_k->set_jni_ids(probe); 1564 } 1565 return probe; 1566} 1567 1568 1569/* jni_id_for for jfieldIds only */ 1570JNIid* InstanceKlass::jni_id_for(int offset) { 1571 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset); 1572 if (probe == NULL) { 1573 probe = jni_id_for_impl(this, offset); 1574 } 1575 return probe; 1576} 1577 1578u2 InstanceKlass::enclosing_method_data(int offset) { 1579 Array<jushort>* inner_class_list = inner_classes(); 1580 if (inner_class_list == NULL) { 1581 return 0; 1582 } 1583 int length = inner_class_list->length(); 1584 if (length % inner_class_next_offset == 0) { 1585 return 0; 1586 } else { 1587 int index = length - enclosing_method_attribute_size; 1588 assert(offset < enclosing_method_attribute_size, "invalid offset"); 1589 return inner_class_list->at(index + offset); 1590 } 1591} 1592 1593void InstanceKlass::set_enclosing_method_indices(u2 class_index, 1594 u2 method_index) { 1595 Array<jushort>* inner_class_list = inner_classes(); 1596 assert (inner_class_list != NULL, "_inner_classes list is not set up"); 1597 int length = inner_class_list->length(); 1598 if (length % inner_class_next_offset == enclosing_method_attribute_size) { 1599 int index = length - enclosing_method_attribute_size; 1600 inner_class_list->at_put( 1601 index + enclosing_method_class_index_offset, class_index); 1602 inner_class_list->at_put( 1603 index + enclosing_method_method_index_offset, method_index); 1604 } 1605} 1606 1607// Lookup or create a jmethodID. 1608// This code is called by the VMThread and JavaThreads so the 1609// locking has to be done very carefully to avoid deadlocks 1610// and/or other cache consistency problems. 1611// 1612jmethodID InstanceKlass::get_jmethod_id(instanceKlassHandle ik_h, methodHandle method_h) { 1613 size_t idnum = (size_t)method_h->method_idnum(); 1614 jmethodID* jmeths = ik_h->methods_jmethod_ids_acquire(); 1615 size_t length = 0; 1616 jmethodID id = NULL; 1617 1618 // We use a double-check locking idiom here because this cache is 1619 // performance sensitive. In the normal system, this cache only 1620 // transitions from NULL to non-NULL which is safe because we use 1621 // release_set_methods_jmethod_ids() to advertise the new cache. 1622 // A partially constructed cache should never be seen by a racing 1623 // thread. We also use release_store_ptr() to save a new jmethodID 1624 // in the cache so a partially constructed jmethodID should never be 1625 // seen either. Cache reads of existing jmethodIDs proceed without a 1626 // lock, but cache writes of a new jmethodID requires uniqueness and 1627 // creation of the cache itself requires no leaks so a lock is 1628 // generally acquired in those two cases. 1629 // 1630 // If the RedefineClasses() API has been used, then this cache can 1631 // grow and we'll have transitions from non-NULL to bigger non-NULL. 1632 // Cache creation requires no leaks and we require safety between all 1633 // cache accesses and freeing of the old cache so a lock is generally 1634 // acquired when the RedefineClasses() API has been used. 1635 1636 if (jmeths != NULL) { 1637 // the cache already exists 1638 if (!ik_h->idnum_can_increment()) { 1639 // the cache can't grow so we can just get the current values 1640 get_jmethod_id_length_value(jmeths, idnum, &length, &id); 1641 } else { 1642 // cache can grow so we have to be more careful 1643 if (Threads::number_of_threads() == 0 || 1644 SafepointSynchronize::is_at_safepoint()) { 1645 // we're single threaded or at a safepoint - no locking needed 1646 get_jmethod_id_length_value(jmeths, idnum, &length, &id); 1647 } else { 1648 MutexLocker ml(JmethodIdCreation_lock); 1649 get_jmethod_id_length_value(jmeths, idnum, &length, &id); 1650 } 1651 } 1652 } 1653 // implied else: 1654 // we need to allocate a cache so default length and id values are good 1655 1656 if (jmeths == NULL || // no cache yet 1657 length <= idnum || // cache is too short 1658 id == NULL) { // cache doesn't contain entry 1659 1660 // This function can be called by the VMThread so we have to do all 1661 // things that might block on a safepoint before grabbing the lock. 1662 // Otherwise, we can deadlock with the VMThread or have a cache 1663 // consistency issue. These vars keep track of what we might have 1664 // to free after the lock is dropped. 1665 jmethodID to_dealloc_id = NULL; 1666 jmethodID* to_dealloc_jmeths = NULL; 1667 1668 // may not allocate new_jmeths or use it if we allocate it 1669 jmethodID* new_jmeths = NULL; 1670 if (length <= idnum) { 1671 // allocate a new cache that might be used 1672 size_t size = MAX2(idnum+1, (size_t)ik_h->idnum_allocated_count()); 1673 new_jmeths = NEW_C_HEAP_ARRAY(jmethodID, size+1, mtClass); 1674 memset(new_jmeths, 0, (size+1)*sizeof(jmethodID)); 1675 // cache size is stored in element[0], other elements offset by one 1676 new_jmeths[0] = (jmethodID)size; 1677 } 1678 1679 // allocate a new jmethodID that might be used 1680 jmethodID new_id = NULL; 1681 if (method_h->is_old() && !method_h->is_obsolete()) { 1682 // The method passed in is old (but not obsolete), we need to use the current version 1683 Method* current_method = ik_h->method_with_idnum((int)idnum); 1684 assert(current_method != NULL, "old and but not obsolete, so should exist"); 1685 new_id = Method::make_jmethod_id(ik_h->class_loader_data(), current_method); 1686 } else { 1687 // It is the current version of the method or an obsolete method, 1688 // use the version passed in 1689 new_id = Method::make_jmethod_id(ik_h->class_loader_data(), method_h()); 1690 } 1691 1692 if (Threads::number_of_threads() == 0 || 1693 SafepointSynchronize::is_at_safepoint()) { 1694 // we're single threaded or at a safepoint - no locking needed 1695 id = get_jmethod_id_fetch_or_update(ik_h, idnum, new_id, new_jmeths, 1696 &to_dealloc_id, &to_dealloc_jmeths); 1697 } else { 1698 MutexLocker ml(JmethodIdCreation_lock); 1699 id = get_jmethod_id_fetch_or_update(ik_h, idnum, new_id, new_jmeths, 1700 &to_dealloc_id, &to_dealloc_jmeths); 1701 } 1702 1703 // The lock has been dropped so we can free resources. 1704 // Free up either the old cache or the new cache if we allocated one. 1705 if (to_dealloc_jmeths != NULL) { 1706 FreeHeap(to_dealloc_jmeths); 1707 } 1708 // free up the new ID since it wasn't needed 1709 if (to_dealloc_id != NULL) { 1710 Method::destroy_jmethod_id(ik_h->class_loader_data(), to_dealloc_id); 1711 } 1712 } 1713 return id; 1714} 1715 1716 1717// Common code to fetch the jmethodID from the cache or update the 1718// cache with the new jmethodID. This function should never do anything 1719// that causes the caller to go to a safepoint or we can deadlock with 1720// the VMThread or have cache consistency issues. 1721// 1722jmethodID InstanceKlass::get_jmethod_id_fetch_or_update( 1723 instanceKlassHandle ik_h, size_t idnum, jmethodID new_id, 1724 jmethodID* new_jmeths, jmethodID* to_dealloc_id_p, 1725 jmethodID** to_dealloc_jmeths_p) { 1726 assert(new_id != NULL, "sanity check"); 1727 assert(to_dealloc_id_p != NULL, "sanity check"); 1728 assert(to_dealloc_jmeths_p != NULL, "sanity check"); 1729 assert(Threads::number_of_threads() == 0 || 1730 SafepointSynchronize::is_at_safepoint() || 1731 JmethodIdCreation_lock->owned_by_self(), "sanity check"); 1732 1733 // reacquire the cache - we are locked, single threaded or at a safepoint 1734 jmethodID* jmeths = ik_h->methods_jmethod_ids_acquire(); 1735 jmethodID id = NULL; 1736 size_t length = 0; 1737 1738 if (jmeths == NULL || // no cache yet 1739 (length = (size_t)jmeths[0]) <= idnum) { // cache is too short 1740 if (jmeths != NULL) { 1741 // copy any existing entries from the old cache 1742 for (size_t index = 0; index < length; index++) { 1743 new_jmeths[index+1] = jmeths[index+1]; 1744 } 1745 *to_dealloc_jmeths_p = jmeths; // save old cache for later delete 1746 } 1747 ik_h->release_set_methods_jmethod_ids(jmeths = new_jmeths); 1748 } else { 1749 // fetch jmethodID (if any) from the existing cache 1750 id = jmeths[idnum+1]; 1751 *to_dealloc_jmeths_p = new_jmeths; // save new cache for later delete 1752 } 1753 if (id == NULL) { 1754 // No matching jmethodID in the existing cache or we have a new 1755 // cache or we just grew the cache. This cache write is done here 1756 // by the first thread to win the foot race because a jmethodID 1757 // needs to be unique once it is generally available. 1758 id = new_id; 1759 1760 // The jmethodID cache can be read while unlocked so we have to 1761 // make sure the new jmethodID is complete before installing it 1762 // in the cache. 1763 OrderAccess::release_store_ptr(&jmeths[idnum+1], id); 1764 } else { 1765 *to_dealloc_id_p = new_id; // save new id for later delete 1766 } 1767 return id; 1768} 1769 1770 1771// Common code to get the jmethodID cache length and the jmethodID 1772// value at index idnum if there is one. 1773// 1774void InstanceKlass::get_jmethod_id_length_value(jmethodID* cache, 1775 size_t idnum, size_t *length_p, jmethodID* id_p) { 1776 assert(cache != NULL, "sanity check"); 1777 assert(length_p != NULL, "sanity check"); 1778 assert(id_p != NULL, "sanity check"); 1779 1780 // cache size is stored in element[0], other elements offset by one 1781 *length_p = (size_t)cache[0]; 1782 if (*length_p <= idnum) { // cache is too short 1783 *id_p = NULL; 1784 } else { 1785 *id_p = cache[idnum+1]; // fetch jmethodID (if any) 1786 } 1787} 1788 1789 1790// Lookup a jmethodID, NULL if not found. Do no blocking, no allocations, no handles 1791jmethodID InstanceKlass::jmethod_id_or_null(Method* method) { 1792 size_t idnum = (size_t)method->method_idnum(); 1793 jmethodID* jmeths = methods_jmethod_ids_acquire(); 1794 size_t length; // length assigned as debugging crumb 1795 jmethodID id = NULL; 1796 if (jmeths != NULL && // If there is a cache 1797 (length = (size_t)jmeths[0]) > idnum) { // and if it is long enough, 1798 id = jmeths[idnum+1]; // Look up the id (may be NULL) 1799 } 1800 return id; 1801} 1802 1803 1804// 1805// Walk the list of dependent nmethods searching for nmethods which 1806// are dependent on the changes that were passed in and mark them for 1807// deoptimization. Returns the number of nmethods found. 1808// 1809int InstanceKlass::mark_dependent_nmethods(DepChange& changes) { 1810 assert_locked_or_safepoint(CodeCache_lock); 1811 int found = 0; 1812 nmethodBucket* b = _dependencies; 1813 while (b != NULL) { 1814 nmethod* nm = b->get_nmethod(); 1815 // since dependencies aren't removed until an nmethod becomes a zombie, 1816 // the dependency list may contain nmethods which aren't alive. 1817 if (nm->is_alive() && !nm->is_marked_for_deoptimization() && nm->check_dependency_on(changes)) { 1818 if (TraceDependencies) { 1819 ResourceMark rm; 1820 tty->print_cr("Marked for deoptimization"); 1821 tty->print_cr(" context = %s", this->external_name()); 1822 changes.print(); 1823 nm->print(); 1824 nm->print_dependencies(); 1825 } 1826 nm->mark_for_deoptimization(); 1827 found++; 1828 } 1829 b = b->next(); 1830 } 1831 return found; 1832} 1833 1834 1835// 1836// Add an nmethodBucket to the list of dependencies for this nmethod. 1837// It's possible that an nmethod has multiple dependencies on this klass 1838// so a count is kept for each bucket to guarantee that creation and 1839// deletion of dependencies is consistent. 1840// 1841void InstanceKlass::add_dependent_nmethod(nmethod* nm) { 1842 assert_locked_or_safepoint(CodeCache_lock); 1843 nmethodBucket* b = _dependencies; 1844 nmethodBucket* last = NULL; 1845 while (b != NULL) { 1846 if (nm == b->get_nmethod()) { 1847 b->increment(); 1848 return; 1849 } 1850 b = b->next(); 1851 } 1852 _dependencies = new nmethodBucket(nm, _dependencies); 1853} 1854 1855 1856// 1857// Decrement count of the nmethod in the dependency list and remove 1858// the bucket competely when the count goes to 0. This method must 1859// find a corresponding bucket otherwise there's a bug in the 1860// recording of dependecies. 1861// 1862void InstanceKlass::remove_dependent_nmethod(nmethod* nm) { 1863 assert_locked_or_safepoint(CodeCache_lock); 1864 nmethodBucket* b = _dependencies; 1865 nmethodBucket* last = NULL; 1866 while (b != NULL) { 1867 if (nm == b->get_nmethod()) { 1868 if (b->decrement() == 0) { 1869 if (last == NULL) { 1870 _dependencies = b->next(); 1871 } else { 1872 last->set_next(b->next()); 1873 } 1874 delete b; 1875 } 1876 return; 1877 } 1878 last = b; 1879 b = b->next(); 1880 } 1881#ifdef ASSERT 1882 tty->print_cr("### %s can't find dependent nmethod:", this->external_name()); 1883 nm->print(); 1884#endif // ASSERT 1885 ShouldNotReachHere(); 1886} 1887 1888 1889#ifndef PRODUCT 1890void InstanceKlass::print_dependent_nmethods(bool verbose) { 1891 nmethodBucket* b = _dependencies; 1892 int idx = 0; 1893 while (b != NULL) { 1894 nmethod* nm = b->get_nmethod(); 1895 tty->print("[%d] count=%d { ", idx++, b->count()); 1896 if (!verbose) { 1897 nm->print_on(tty, "nmethod"); 1898 tty->print_cr(" } "); 1899 } else { 1900 nm->print(); 1901 nm->print_dependencies(); 1902 tty->print_cr("--- } "); 1903 } 1904 b = b->next(); 1905 } 1906} 1907 1908 1909bool InstanceKlass::is_dependent_nmethod(nmethod* nm) { 1910 nmethodBucket* b = _dependencies; 1911 while (b != NULL) { 1912 if (nm == b->get_nmethod()) { 1913 return true; 1914 } 1915 b = b->next(); 1916 } 1917 return false; 1918} 1919#endif //PRODUCT 1920 1921 1922// Garbage collection 1923 1924#ifdef ASSERT 1925template <class T> void assert_is_in(T *p) { 1926 T heap_oop = oopDesc::load_heap_oop(p); 1927 if (!oopDesc::is_null(heap_oop)) { 1928 oop o = oopDesc::decode_heap_oop_not_null(heap_oop); 1929 assert(Universe::heap()->is_in(o), "should be in heap"); 1930 } 1931} 1932template <class T> void assert_is_in_closed_subset(T *p) { 1933 T heap_oop = oopDesc::load_heap_oop(p); 1934 if (!oopDesc::is_null(heap_oop)) { 1935 oop o = oopDesc::decode_heap_oop_not_null(heap_oop); 1936 assert(Universe::heap()->is_in_closed_subset(o), 1937 err_msg("should be in closed *p " INTPTR_FORMAT " " INTPTR_FORMAT, (address)p, (address)o)); 1938 } 1939} 1940template <class T> void assert_is_in_reserved(T *p) { 1941 T heap_oop = oopDesc::load_heap_oop(p); 1942 if (!oopDesc::is_null(heap_oop)) { 1943 oop o = oopDesc::decode_heap_oop_not_null(heap_oop); 1944 assert(Universe::heap()->is_in_reserved(o), "should be in reserved"); 1945 } 1946} 1947template <class T> void assert_nothing(T *p) {} 1948 1949#else 1950template <class T> void assert_is_in(T *p) {} 1951template <class T> void assert_is_in_closed_subset(T *p) {} 1952template <class T> void assert_is_in_reserved(T *p) {} 1953template <class T> void assert_nothing(T *p) {} 1954#endif // ASSERT 1955 1956// 1957// Macros that iterate over areas of oops which are specialized on type of 1958// oop pointer either narrow or wide, depending on UseCompressedOops 1959// 1960// Parameters are: 1961// T - type of oop to point to (either oop or narrowOop) 1962// start_p - starting pointer for region to iterate over 1963// count - number of oops or narrowOops to iterate over 1964// do_oop - action to perform on each oop (it's arbitrary C code which 1965// makes it more efficient to put in a macro rather than making 1966// it a template function) 1967// assert_fn - assert function which is template function because performance 1968// doesn't matter when enabled. 1969#define InstanceKlass_SPECIALIZED_OOP_ITERATE( \ 1970 T, start_p, count, do_oop, \ 1971 assert_fn) \ 1972{ \ 1973 T* p = (T*)(start_p); \ 1974 T* const end = p + (count); \ 1975 while (p < end) { \ 1976 (assert_fn)(p); \ 1977 do_oop; \ 1978 ++p; \ 1979 } \ 1980} 1981 1982#define InstanceKlass_SPECIALIZED_OOP_REVERSE_ITERATE( \ 1983 T, start_p, count, do_oop, \ 1984 assert_fn) \ 1985{ \ 1986 T* const start = (T*)(start_p); \ 1987 T* p = start + (count); \ 1988 while (start < p) { \ 1989 --p; \ 1990 (assert_fn)(p); \ 1991 do_oop; \ 1992 } \ 1993} 1994 1995#define InstanceKlass_SPECIALIZED_BOUNDED_OOP_ITERATE( \ 1996 T, start_p, count, low, high, \ 1997 do_oop, assert_fn) \ 1998{ \ 1999 T* const l = (T*)(low); \ 2000 T* const h = (T*)(high); \ 2001 assert(mask_bits((intptr_t)l, sizeof(T)-1) == 0 && \ 2002 mask_bits((intptr_t)h, sizeof(T)-1) == 0, \ 2003 "bounded region must be properly aligned"); \ 2004 T* p = (T*)(start_p); \ 2005 T* end = p + (count); \ 2006 if (p < l) p = l; \ 2007 if (end > h) end = h; \ 2008 while (p < end) { \ 2009 (assert_fn)(p); \ 2010 do_oop; \ 2011 ++p; \ 2012 } \ 2013} 2014 2015 2016// The following macros call specialized macros, passing either oop or 2017// narrowOop as the specialization type. These test the UseCompressedOops 2018// flag. 2019#define InstanceKlass_OOP_MAP_ITERATE(obj, do_oop, assert_fn) \ 2020{ \ 2021 /* Compute oopmap block range. The common case \ 2022 is nonstatic_oop_map_size == 1. */ \ 2023 OopMapBlock* map = start_of_nonstatic_oop_maps(); \ 2024 OopMapBlock* const end_map = map + nonstatic_oop_map_count(); \ 2025 if (UseCompressedOops) { \ 2026 while (map < end_map) { \ 2027 InstanceKlass_SPECIALIZED_OOP_ITERATE(narrowOop, \ 2028 obj->obj_field_addr<narrowOop>(map->offset()), map->count(), \ 2029 do_oop, assert_fn) \ 2030 ++map; \ 2031 } \ 2032 } else { \ 2033 while (map < end_map) { \ 2034 InstanceKlass_SPECIALIZED_OOP_ITERATE(oop, \ 2035 obj->obj_field_addr<oop>(map->offset()), map->count(), \ 2036 do_oop, assert_fn) \ 2037 ++map; \ 2038 } \ 2039 } \ 2040} 2041 2042#define InstanceKlass_OOP_MAP_REVERSE_ITERATE(obj, do_oop, assert_fn) \ 2043{ \ 2044 OopMapBlock* const start_map = start_of_nonstatic_oop_maps(); \ 2045 OopMapBlock* map = start_map + nonstatic_oop_map_count(); \ 2046 if (UseCompressedOops) { \ 2047 while (start_map < map) { \ 2048 --map; \ 2049 InstanceKlass_SPECIALIZED_OOP_REVERSE_ITERATE(narrowOop, \ 2050 obj->obj_field_addr<narrowOop>(map->offset()), map->count(), \ 2051 do_oop, assert_fn) \ 2052 } \ 2053 } else { \ 2054 while (start_map < map) { \ 2055 --map; \ 2056 InstanceKlass_SPECIALIZED_OOP_REVERSE_ITERATE(oop, \ 2057 obj->obj_field_addr<oop>(map->offset()), map->count(), \ 2058 do_oop, assert_fn) \ 2059 } \ 2060 } \ 2061} 2062 2063#define InstanceKlass_BOUNDED_OOP_MAP_ITERATE(obj, low, high, do_oop, \ 2064 assert_fn) \ 2065{ \ 2066 /* Compute oopmap block range. The common case is \ 2067 nonstatic_oop_map_size == 1, so we accept the \ 2068 usually non-existent extra overhead of examining \ 2069 all the maps. */ \ 2070 OopMapBlock* map = start_of_nonstatic_oop_maps(); \ 2071 OopMapBlock* const end_map = map + nonstatic_oop_map_count(); \ 2072 if (UseCompressedOops) { \ 2073 while (map < end_map) { \ 2074 InstanceKlass_SPECIALIZED_BOUNDED_OOP_ITERATE(narrowOop, \ 2075 obj->obj_field_addr<narrowOop>(map->offset()), map->count(), \ 2076 low, high, \ 2077 do_oop, assert_fn) \ 2078 ++map; \ 2079 } \ 2080 } else { \ 2081 while (map < end_map) { \ 2082 InstanceKlass_SPECIALIZED_BOUNDED_OOP_ITERATE(oop, \ 2083 obj->obj_field_addr<oop>(map->offset()), map->count(), \ 2084 low, high, \ 2085 do_oop, assert_fn) \ 2086 ++map; \ 2087 } \ 2088 } \ 2089} 2090 2091void InstanceKlass::oop_follow_contents(oop obj) { 2092 assert(obj != NULL, "can't follow the content of NULL object"); 2093 MarkSweep::follow_klass(obj->klass()); 2094 InstanceKlass_OOP_MAP_ITERATE( \ 2095 obj, \ 2096 MarkSweep::mark_and_push(p), \ 2097 assert_is_in_closed_subset) 2098} 2099 2100#if INCLUDE_ALL_GCS 2101void InstanceKlass::oop_follow_contents(ParCompactionManager* cm, 2102 oop obj) { 2103 assert(obj != NULL, "can't follow the content of NULL object"); 2104 PSParallelCompact::follow_klass(cm, obj->klass()); 2105 // Only mark the header and let the scan of the meta-data mark 2106 // everything else. 2107 InstanceKlass_OOP_MAP_ITERATE( \ 2108 obj, \ 2109 PSParallelCompact::mark_and_push(cm, p), \ 2110 assert_is_in) 2111} 2112#endif // INCLUDE_ALL_GCS 2113 2114// closure's do_metadata() method dictates whether the given closure should be 2115// applied to the klass ptr in the object header. 2116 2117#define if_do_metadata_checked(closure, nv_suffix) \ 2118 /* Make sure the non-virtual and the virtual versions match. */ \ 2119 assert(closure->do_metadata##nv_suffix() == closure->do_metadata(), \ 2120 "Inconsistency in do_metadata"); \ 2121 if (closure->do_metadata##nv_suffix()) 2122 2123#define InstanceKlass_OOP_OOP_ITERATE_DEFN(OopClosureType, nv_suffix) \ 2124 \ 2125int InstanceKlass::oop_oop_iterate##nv_suffix(oop obj, OopClosureType* closure) { \ 2126 SpecializationStats::record_iterate_call##nv_suffix(SpecializationStats::ik);\ 2127 /* header */ \ 2128 if_do_metadata_checked(closure, nv_suffix) { \ 2129 closure->do_klass##nv_suffix(obj->klass()); \ 2130 } \ 2131 InstanceKlass_OOP_MAP_ITERATE( \ 2132 obj, \ 2133 SpecializationStats:: \ 2134 record_do_oop_call##nv_suffix(SpecializationStats::ik); \ 2135 (closure)->do_oop##nv_suffix(p), \ 2136 assert_is_in_closed_subset) \ 2137 return size_helper(); \ 2138} 2139 2140#if INCLUDE_ALL_GCS 2141#define InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DEFN(OopClosureType, nv_suffix) \ 2142 \ 2143int InstanceKlass::oop_oop_iterate_backwards##nv_suffix(oop obj, \ 2144 OopClosureType* closure) { \ 2145 SpecializationStats::record_iterate_call##nv_suffix(SpecializationStats::ik); \ 2146 /* header */ \ 2147 if_do_metadata_checked(closure, nv_suffix) { \ 2148 closure->do_klass##nv_suffix(obj->klass()); \ 2149 } \ 2150 /* instance variables */ \ 2151 InstanceKlass_OOP_MAP_REVERSE_ITERATE( \ 2152 obj, \ 2153 SpecializationStats::record_do_oop_call##nv_suffix(SpecializationStats::ik);\ 2154 (closure)->do_oop##nv_suffix(p), \ 2155 assert_is_in_closed_subset) \ 2156 return size_helper(); \ 2157} 2158#endif // INCLUDE_ALL_GCS 2159 2160#define InstanceKlass_OOP_OOP_ITERATE_DEFN_m(OopClosureType, nv_suffix) \ 2161 \ 2162int InstanceKlass::oop_oop_iterate##nv_suffix##_m(oop obj, \ 2163 OopClosureType* closure, \ 2164 MemRegion mr) { \ 2165 SpecializationStats::record_iterate_call##nv_suffix(SpecializationStats::ik);\ 2166 if_do_metadata_checked(closure, nv_suffix) { \ 2167 if (mr.contains(obj)) { \ 2168 closure->do_klass##nv_suffix(obj->klass()); \ 2169 } \ 2170 } \ 2171 InstanceKlass_BOUNDED_OOP_MAP_ITERATE( \ 2172 obj, mr.start(), mr.end(), \ 2173 (closure)->do_oop##nv_suffix(p), \ 2174 assert_is_in_closed_subset) \ 2175 return size_helper(); \ 2176} 2177 2178ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_DEFN) 2179ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceKlass_OOP_OOP_ITERATE_DEFN) 2180ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_DEFN_m) 2181ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceKlass_OOP_OOP_ITERATE_DEFN_m) 2182#if INCLUDE_ALL_GCS 2183ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DEFN) 2184ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DEFN) 2185#endif // INCLUDE_ALL_GCS 2186 2187int InstanceKlass::oop_adjust_pointers(oop obj) { 2188 int size = size_helper(); 2189 InstanceKlass_OOP_MAP_ITERATE( \ 2190 obj, \ 2191 MarkSweep::adjust_pointer(p), \ 2192 assert_is_in) 2193 return size; 2194} 2195 2196#if INCLUDE_ALL_GCS 2197void InstanceKlass::oop_push_contents(PSPromotionManager* pm, oop obj) { 2198 InstanceKlass_OOP_MAP_REVERSE_ITERATE( \ 2199 obj, \ 2200 if (PSScavenge::should_scavenge(p)) { \ 2201 pm->claim_or_forward_depth(p); \ 2202 }, \ 2203 assert_nothing ) 2204} 2205 2206int InstanceKlass::oop_update_pointers(ParCompactionManager* cm, oop obj) { 2207 int size = size_helper(); 2208 InstanceKlass_OOP_MAP_ITERATE( \ 2209 obj, \ 2210 PSParallelCompact::adjust_pointer(p), \ 2211 assert_is_in) 2212 return size; 2213} 2214 2215#endif // INCLUDE_ALL_GCS 2216 2217void InstanceKlass::clean_implementors_list(BoolObjectClosure* is_alive) { 2218 assert(is_loader_alive(is_alive), "this klass should be live"); 2219 if (is_interface()) { 2220 if (ClassUnloading) { 2221 Klass* impl = implementor(); 2222 if (impl != NULL) { 2223 if (!impl->is_loader_alive(is_alive)) { 2224 // remove this guy 2225 Klass** klass = adr_implementor(); 2226 assert(klass != NULL, "null klass"); 2227 if (klass != NULL) { 2228 *klass = NULL; 2229 } 2230 } 2231 } 2232 } 2233 } 2234} 2235 2236void InstanceKlass::clean_method_data(BoolObjectClosure* is_alive) { 2237 for (int m = 0; m < methods()->length(); m++) { 2238 MethodData* mdo = methods()->at(m)->method_data(); 2239 if (mdo != NULL) { 2240 mdo->clean_method_data(is_alive); 2241 } 2242 } 2243} 2244 2245 2246static void remove_unshareable_in_class(Klass* k) { 2247 // remove klass's unshareable info 2248 k->remove_unshareable_info(); 2249} 2250 2251void InstanceKlass::remove_unshareable_info() { 2252 Klass::remove_unshareable_info(); 2253 // Unlink the class 2254 if (is_linked()) { 2255 unlink_class(); 2256 } 2257 init_implementor(); 2258 2259 constants()->remove_unshareable_info(); 2260 2261 for (int i = 0; i < methods()->length(); i++) { 2262 Method* m = methods()->at(i); 2263 m->remove_unshareable_info(); 2264 } 2265 2266 // do array classes also. 2267 array_klasses_do(remove_unshareable_in_class); 2268} 2269 2270void restore_unshareable_in_class(Klass* k, TRAPS) { 2271 k->restore_unshareable_info(CHECK); 2272} 2273 2274void InstanceKlass::restore_unshareable_info(TRAPS) { 2275 Klass::restore_unshareable_info(CHECK); 2276 instanceKlassHandle ik(THREAD, this); 2277 2278 Array<Method*>* methods = ik->methods(); 2279 int num_methods = methods->length(); 2280 for (int index2 = 0; index2 < num_methods; ++index2) { 2281 methodHandle m(THREAD, methods->at(index2)); 2282 m->restore_unshareable_info(CHECK); 2283 } 2284 if (JvmtiExport::has_redefined_a_class()) { 2285 // Reinitialize vtable because RedefineClasses may have changed some 2286 // entries in this vtable for super classes so the CDS vtable might 2287 // point to old or obsolete entries. RedefineClasses doesn't fix up 2288 // vtables in the shared system dictionary, only the main one. 2289 // It also redefines the itable too so fix that too. 2290 ResourceMark rm(THREAD); 2291 ik->vtable()->initialize_vtable(false, CHECK); 2292 ik->itable()->initialize_itable(false, CHECK); 2293 } 2294 2295 // restore constant pool resolved references 2296 ik->constants()->restore_unshareable_info(CHECK); 2297 2298 ik->array_klasses_do(restore_unshareable_in_class, CHECK); 2299} 2300 2301static void clear_all_breakpoints(Method* m) { 2302 m->clear_all_breakpoints(); 2303} 2304 2305 2306void InstanceKlass::notify_unload_class(InstanceKlass* ik) { 2307 // notify the debugger 2308 if (JvmtiExport::should_post_class_unload()) { 2309 JvmtiExport::post_class_unload(ik); 2310 } 2311 2312 // notify ClassLoadingService of class unload 2313 ClassLoadingService::notify_class_unloaded(ik); 2314} 2315 2316void InstanceKlass::release_C_heap_structures(InstanceKlass* ik) { 2317 // Clean up C heap 2318 ik->release_C_heap_structures(); 2319 ik->constants()->release_C_heap_structures(); 2320} 2321 2322void InstanceKlass::release_C_heap_structures() { 2323 2324 // Can't release the constant pool here because the constant pool can be 2325 // deallocated separately from the InstanceKlass for default methods and 2326 // redefine classes. 2327 2328 // Deallocate oop map cache 2329 if (_oop_map_cache != NULL) { 2330 delete _oop_map_cache; 2331 _oop_map_cache = NULL; 2332 } 2333 2334 // Deallocate JNI identifiers for jfieldIDs 2335 JNIid::deallocate(jni_ids()); 2336 set_jni_ids(NULL); 2337 2338 jmethodID* jmeths = methods_jmethod_ids_acquire(); 2339 if (jmeths != (jmethodID*)NULL) { 2340 release_set_methods_jmethod_ids(NULL); 2341 FreeHeap(jmeths); 2342 } 2343 2344 // Deallocate MemberNameTable 2345 { 2346 Mutex* lock_or_null = SafepointSynchronize::is_at_safepoint() ? NULL : MemberNameTable_lock; 2347 MutexLockerEx ml(lock_or_null, Mutex::_no_safepoint_check_flag); 2348 MemberNameTable* mnt = member_names(); 2349 if (mnt != NULL) { 2350 delete mnt; 2351 set_member_names(NULL); 2352 } 2353 } 2354 2355 // release dependencies 2356 nmethodBucket* b = _dependencies; 2357 _dependencies = NULL; 2358 while (b != NULL) { 2359 nmethodBucket* next = b->next(); 2360 delete b; 2361 b = next; 2362 } 2363 2364 // Deallocate breakpoint records 2365 if (breakpoints() != 0x0) { 2366 methods_do(clear_all_breakpoints); 2367 assert(breakpoints() == 0x0, "should have cleared breakpoints"); 2368 } 2369 2370 // deallocate information about previous versions 2371 if (_previous_versions != NULL) { 2372 for (int i = _previous_versions->length() - 1; i >= 0; i--) { 2373 PreviousVersionNode * pv_node = _previous_versions->at(i); 2374 delete pv_node; 2375 } 2376 delete _previous_versions; 2377 _previous_versions = NULL; 2378 } 2379 2380 // deallocate the cached class file 2381 if (_cached_class_file != NULL) { 2382 os::free(_cached_class_file, mtClass); 2383 _cached_class_file = NULL; 2384 } 2385 2386 // Decrement symbol reference counts associated with the unloaded class. 2387 if (_name != NULL) _name->decrement_refcount(); 2388 // unreference array name derived from this class name (arrays of an unloaded 2389 // class can't be referenced anymore). 2390 if (_array_name != NULL) _array_name->decrement_refcount(); 2391 if (_source_debug_extension != NULL) FREE_C_HEAP_ARRAY(char, _source_debug_extension, mtClass); 2392 2393 assert(_total_instanceKlass_count >= 1, "Sanity check"); 2394 Atomic::dec(&_total_instanceKlass_count); 2395} 2396 2397void InstanceKlass::set_source_debug_extension(char* array, int length) { 2398 if (array == NULL) { 2399 _source_debug_extension = NULL; 2400 } else { 2401 // Adding one to the attribute length in order to store a null terminator 2402 // character could cause an overflow because the attribute length is 2403 // already coded with an u4 in the classfile, but in practice, it's 2404 // unlikely to happen. 2405 assert((length+1) > length, "Overflow checking"); 2406 char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass); 2407 for (int i = 0; i < length; i++) { 2408 sde[i] = array[i]; 2409 } 2410 sde[length] = '\0'; 2411 _source_debug_extension = sde; 2412 } 2413} 2414 2415address InstanceKlass::static_field_addr(int offset) { 2416 return (address)(offset + InstanceMirrorKlass::offset_of_static_fields() + cast_from_oop<intptr_t>(java_mirror())); 2417} 2418 2419 2420const char* InstanceKlass::signature_name() const { 2421 int hash_len = 0; 2422 char hash_buf[40]; 2423 2424 // If this is an anonymous class, append a hash to make the name unique 2425 if (is_anonymous()) { 2426 intptr_t hash = (java_mirror() != NULL) ? java_mirror()->identity_hash() : 0; 2427 sprintf(hash_buf, "/" UINTX_FORMAT, (uintx)hash); 2428 hash_len = (int)strlen(hash_buf); 2429 } 2430 2431 // Get the internal name as a c string 2432 const char* src = (const char*) (name()->as_C_string()); 2433 const int src_length = (int)strlen(src); 2434 2435 char* dest = NEW_RESOURCE_ARRAY(char, src_length + hash_len + 3); 2436 2437 // Add L as type indicator 2438 int dest_index = 0; 2439 dest[dest_index++] = 'L'; 2440 2441 // Add the actual class name 2442 for (int src_index = 0; src_index < src_length; ) { 2443 dest[dest_index++] = src[src_index++]; 2444 } 2445 2446 // If we have a hash, append it 2447 for (int hash_index = 0; hash_index < hash_len; ) { 2448 dest[dest_index++] = hash_buf[hash_index++]; 2449 } 2450 2451 // Add the semicolon and the NULL 2452 dest[dest_index++] = ';'; 2453 dest[dest_index] = '\0'; 2454 return dest; 2455} 2456 2457// different verisons of is_same_class_package 2458bool InstanceKlass::is_same_class_package(Klass* class2) { 2459 Klass* class1 = this; 2460 oop classloader1 = InstanceKlass::cast(class1)->class_loader(); 2461 Symbol* classname1 = class1->name(); 2462 2463 if (class2->oop_is_objArray()) { 2464 class2 = ObjArrayKlass::cast(class2)->bottom_klass(); 2465 } 2466 oop classloader2; 2467 if (class2->oop_is_instance()) { 2468 classloader2 = InstanceKlass::cast(class2)->class_loader(); 2469 } else { 2470 assert(class2->oop_is_typeArray(), "should be type array"); 2471 classloader2 = NULL; 2472 } 2473 Symbol* classname2 = class2->name(); 2474 2475 return InstanceKlass::is_same_class_package(classloader1, classname1, 2476 classloader2, classname2); 2477} 2478 2479bool InstanceKlass::is_same_class_package(oop classloader2, Symbol* classname2) { 2480 Klass* class1 = this; 2481 oop classloader1 = InstanceKlass::cast(class1)->class_loader(); 2482 Symbol* classname1 = class1->name(); 2483 2484 return InstanceKlass::is_same_class_package(classloader1, classname1, 2485 classloader2, classname2); 2486} 2487 2488// return true if two classes are in the same package, classloader 2489// and classname information is enough to determine a class's package 2490bool InstanceKlass::is_same_class_package(oop class_loader1, Symbol* class_name1, 2491 oop class_loader2, Symbol* class_name2) { 2492 if (class_loader1 != class_loader2) { 2493 return false; 2494 } else if (class_name1 == class_name2) { 2495 return true; // skip painful bytewise comparison 2496 } else { 2497 ResourceMark rm; 2498 2499 // The Symbol*'s are in UTF8 encoding. Since we only need to check explicitly 2500 // for ASCII characters ('/', 'L', '['), we can keep them in UTF8 encoding. 2501 // Otherwise, we just compare jbyte values between the strings. 2502 const jbyte *name1 = class_name1->base(); 2503 const jbyte *name2 = class_name2->base(); 2504 2505 const jbyte *last_slash1 = UTF8::strrchr(name1, class_name1->utf8_length(), '/'); 2506 const jbyte *last_slash2 = UTF8::strrchr(name2, class_name2->utf8_length(), '/'); 2507 2508 if ((last_slash1 == NULL) || (last_slash2 == NULL)) { 2509 // One of the two doesn't have a package. Only return true 2510 // if the other one also doesn't have a package. 2511 return last_slash1 == last_slash2; 2512 } else { 2513 // Skip over '['s 2514 if (*name1 == '[') { 2515 do { 2516 name1++; 2517 } while (*name1 == '['); 2518 if (*name1 != 'L') { 2519 // Something is terribly wrong. Shouldn't be here. 2520 return false; 2521 } 2522 } 2523 if (*name2 == '[') { 2524 do { 2525 name2++; 2526 } while (*name2 == '['); 2527 if (*name2 != 'L') { 2528 // Something is terribly wrong. Shouldn't be here. 2529 return false; 2530 } 2531 } 2532 2533 // Check that package part is identical 2534 int length1 = last_slash1 - name1; 2535 int length2 = last_slash2 - name2; 2536 2537 return UTF8::equal(name1, length1, name2, length2); 2538 } 2539 } 2540} 2541 2542// Returns true iff super_method can be overridden by a method in targetclassname 2543// See JSL 3rd edition 8.4.6.1 2544// Assumes name-signature match 2545// "this" is InstanceKlass of super_method which must exist 2546// note that the InstanceKlass of the method in the targetclassname has not always been created yet 2547bool InstanceKlass::is_override(methodHandle super_method, Handle targetclassloader, Symbol* targetclassname, TRAPS) { 2548 // Private methods can not be overridden 2549 if (super_method->is_private()) { 2550 return false; 2551 } 2552 // If super method is accessible, then override 2553 if ((super_method->is_protected()) || 2554 (super_method->is_public())) { 2555 return true; 2556 } 2557 // Package-private methods are not inherited outside of package 2558 assert(super_method->is_package_private(), "must be package private"); 2559 return(is_same_class_package(targetclassloader(), targetclassname)); 2560} 2561 2562/* defined for now in jvm.cpp, for historical reasons *-- 2563Klass* InstanceKlass::compute_enclosing_class_impl(instanceKlassHandle self, 2564 Symbol*& simple_name_result, TRAPS) { 2565 ... 2566} 2567*/ 2568 2569// tell if two classes have the same enclosing class (at package level) 2570bool InstanceKlass::is_same_package_member_impl(instanceKlassHandle class1, 2571 Klass* class2_oop, TRAPS) { 2572 if (class2_oop == class1()) return true; 2573 if (!class2_oop->oop_is_instance()) return false; 2574 instanceKlassHandle class2(THREAD, class2_oop); 2575 2576 // must be in same package before we try anything else 2577 if (!class1->is_same_class_package(class2->class_loader(), class2->name())) 2578 return false; 2579 2580 // As long as there is an outer1.getEnclosingClass, 2581 // shift the search outward. 2582 instanceKlassHandle outer1 = class1; 2583 for (;;) { 2584 // As we walk along, look for equalities between outer1 and class2. 2585 // Eventually, the walks will terminate as outer1 stops 2586 // at the top-level class around the original class. 2587 bool ignore_inner_is_member; 2588 Klass* next = outer1->compute_enclosing_class(&ignore_inner_is_member, 2589 CHECK_false); 2590 if (next == NULL) break; 2591 if (next == class2()) return true; 2592 outer1 = instanceKlassHandle(THREAD, next); 2593 } 2594 2595 // Now do the same for class2. 2596 instanceKlassHandle outer2 = class2; 2597 for (;;) { 2598 bool ignore_inner_is_member; 2599 Klass* next = outer2->compute_enclosing_class(&ignore_inner_is_member, 2600 CHECK_false); 2601 if (next == NULL) break; 2602 // Might as well check the new outer against all available values. 2603 if (next == class1()) return true; 2604 if (next == outer1()) return true; 2605 outer2 = instanceKlassHandle(THREAD, next); 2606 } 2607 2608 // If by this point we have not found an equality between the 2609 // two classes, we know they are in separate package members. 2610 return false; 2611} 2612 2613 2614jint InstanceKlass::compute_modifier_flags(TRAPS) const { 2615 jint access = access_flags().as_int(); 2616 2617 // But check if it happens to be member class. 2618 instanceKlassHandle ik(THREAD, this); 2619 InnerClassesIterator iter(ik); 2620 for (; !iter.done(); iter.next()) { 2621 int ioff = iter.inner_class_info_index(); 2622 // Inner class attribute can be zero, skip it. 2623 // Strange but true: JVM spec. allows null inner class refs. 2624 if (ioff == 0) continue; 2625 2626 // only look at classes that are already loaded 2627 // since we are looking for the flags for our self. 2628 Symbol* inner_name = ik->constants()->klass_name_at(ioff); 2629 if ((ik->name() == inner_name)) { 2630 // This is really a member class. 2631 access = iter.inner_access_flags(); 2632 break; 2633 } 2634 } 2635 // Remember to strip ACC_SUPER bit 2636 return (access & (~JVM_ACC_SUPER)) & JVM_ACC_WRITTEN_FLAGS; 2637} 2638 2639jint InstanceKlass::jvmti_class_status() const { 2640 jint result = 0; 2641 2642 if (is_linked()) { 2643 result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED; 2644 } 2645 2646 if (is_initialized()) { 2647 assert(is_linked(), "Class status is not consistent"); 2648 result |= JVMTI_CLASS_STATUS_INITIALIZED; 2649 } 2650 if (is_in_error_state()) { 2651 result |= JVMTI_CLASS_STATUS_ERROR; 2652 } 2653 return result; 2654} 2655 2656Method* InstanceKlass::method_at_itable(Klass* holder, int index, TRAPS) { 2657 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable(); 2658 int method_table_offset_in_words = ioe->offset()/wordSize; 2659 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words()) 2660 / itableOffsetEntry::size(); 2661 2662 for (int cnt = 0 ; ; cnt ++, ioe ++) { 2663 // If the interface isn't implemented by the receiver class, 2664 // the VM should throw IncompatibleClassChangeError. 2665 if (cnt >= nof_interfaces) { 2666 THROW_NULL(vmSymbols::java_lang_IncompatibleClassChangeError()); 2667 } 2668 2669 Klass* ik = ioe->interface_klass(); 2670 if (ik == holder) break; 2671 } 2672 2673 itableMethodEntry* ime = ioe->first_method_entry(this); 2674 Method* m = ime[index].method(); 2675 if (m == NULL) { 2676 THROW_NULL(vmSymbols::java_lang_AbstractMethodError()); 2677 } 2678 return m; 2679} 2680 2681 2682#if INCLUDE_JVMTI 2683// update default_methods for redefineclasses for methods that are 2684// not yet in the vtable due to concurrent subclass define and superinterface 2685// redefinition 2686// Note: those in the vtable, should have been updated via adjust_method_entries 2687void InstanceKlass::adjust_default_methods(Method** old_methods, Method** new_methods, 2688 int methods_length, bool* trace_name_printed) { 2689 // search the default_methods for uses of either obsolete or EMCP methods 2690 if (default_methods() != NULL) { 2691 for (int j = 0; j < methods_length; j++) { 2692 Method* old_method = old_methods[j]; 2693 Method* new_method = new_methods[j]; 2694 2695 for (int index = 0; index < default_methods()->length(); index ++) { 2696 if (default_methods()->at(index) == old_method) { 2697 default_methods()->at_put(index, new_method); 2698 if (RC_TRACE_IN_RANGE(0x00100000, 0x00400000)) { 2699 if (!(*trace_name_printed)) { 2700 // RC_TRACE_MESG macro has an embedded ResourceMark 2701 RC_TRACE_MESG(("adjust: klassname=%s default methods from name=%s", 2702 external_name(), 2703 old_method->method_holder()->external_name())); 2704 *trace_name_printed = true; 2705 } 2706 RC_TRACE(0x00100000, ("default method update: %s(%s) ", 2707 new_method->name()->as_C_string(), 2708 new_method->signature()->as_C_string())); 2709 } 2710 } 2711 } 2712 } 2713 } 2714} 2715#endif // INCLUDE_JVMTI 2716 2717// On-stack replacement stuff 2718void InstanceKlass::add_osr_nmethod(nmethod* n) { 2719 // only one compilation can be active 2720 NEEDS_CLEANUP 2721 // This is a short non-blocking critical region, so the no safepoint check is ok. 2722 OsrList_lock->lock_without_safepoint_check(); 2723 assert(n->is_osr_method(), "wrong kind of nmethod"); 2724 n->set_osr_link(osr_nmethods_head()); 2725 set_osr_nmethods_head(n); 2726 // Raise the highest osr level if necessary 2727 if (TieredCompilation) { 2728 Method* m = n->method(); 2729 m->set_highest_osr_comp_level(MAX2(m->highest_osr_comp_level(), n->comp_level())); 2730 } 2731 // Remember to unlock again 2732 OsrList_lock->unlock(); 2733 2734 // Get rid of the osr methods for the same bci that have lower levels. 2735 if (TieredCompilation) { 2736 for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) { 2737 nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true); 2738 if (inv != NULL && inv->is_in_use()) { 2739 inv->make_not_entrant(); 2740 } 2741 } 2742 } 2743} 2744 2745 2746void InstanceKlass::remove_osr_nmethod(nmethod* n) { 2747 // This is a short non-blocking critical region, so the no safepoint check is ok. 2748 OsrList_lock->lock_without_safepoint_check(); 2749 assert(n->is_osr_method(), "wrong kind of nmethod"); 2750 nmethod* last = NULL; 2751 nmethod* cur = osr_nmethods_head(); 2752 int max_level = CompLevel_none; // Find the max comp level excluding n 2753 Method* m = n->method(); 2754 // Search for match 2755 while(cur != NULL && cur != n) { 2756 if (TieredCompilation && m == cur->method()) { 2757 // Find max level before n 2758 max_level = MAX2(max_level, cur->comp_level()); 2759 } 2760 last = cur; 2761 cur = cur->osr_link(); 2762 } 2763 nmethod* next = NULL; 2764 if (cur == n) { 2765 next = cur->osr_link(); 2766 if (last == NULL) { 2767 // Remove first element 2768 set_osr_nmethods_head(next); 2769 } else { 2770 last->set_osr_link(next); 2771 } 2772 } 2773 n->set_osr_link(NULL); 2774 if (TieredCompilation) { 2775 cur = next; 2776 while (cur != NULL) { 2777 // Find max level after n 2778 if (m == cur->method()) { 2779 max_level = MAX2(max_level, cur->comp_level()); 2780 } 2781 cur = cur->osr_link(); 2782 } 2783 m->set_highest_osr_comp_level(max_level); 2784 } 2785 // Remember to unlock again 2786 OsrList_lock->unlock(); 2787} 2788 2789nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const { 2790 // This is a short non-blocking critical region, so the no safepoint check is ok. 2791 OsrList_lock->lock_without_safepoint_check(); 2792 nmethod* osr = osr_nmethods_head(); 2793 nmethod* best = NULL; 2794 while (osr != NULL) { 2795 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain"); 2796 // There can be a time when a c1 osr method exists but we are waiting 2797 // for a c2 version. When c2 completes its osr nmethod we will trash 2798 // the c1 version and only be able to find the c2 version. However 2799 // while we overflow in the c1 code at back branches we don't want to 2800 // try and switch to the same code as we are already running 2801 2802 if (osr->method() == m && 2803 (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) { 2804 if (match_level) { 2805 if (osr->comp_level() == comp_level) { 2806 // Found a match - return it. 2807 OsrList_lock->unlock(); 2808 return osr; 2809 } 2810 } else { 2811 if (best == NULL || (osr->comp_level() > best->comp_level())) { 2812 if (osr->comp_level() == CompLevel_highest_tier) { 2813 // Found the best possible - return it. 2814 OsrList_lock->unlock(); 2815 return osr; 2816 } 2817 best = osr; 2818 } 2819 } 2820 } 2821 osr = osr->osr_link(); 2822 } 2823 OsrList_lock->unlock(); 2824 if (best != NULL && best->comp_level() >= comp_level && match_level == false) { 2825 return best; 2826 } 2827 return NULL; 2828} 2829 2830void InstanceKlass::add_member_name(int index, Handle mem_name) { 2831 jweak mem_name_wref = JNIHandles::make_weak_global(mem_name); 2832 MutexLocker ml(MemberNameTable_lock); 2833 assert(0 <= index && index < idnum_allocated_count(), "index is out of bounds"); 2834 DEBUG_ONLY(No_Safepoint_Verifier nsv); 2835 2836 if (_member_names == NULL) { 2837 _member_names = new (ResourceObj::C_HEAP, mtClass) MemberNameTable(idnum_allocated_count()); 2838 } 2839 _member_names->add_member_name(index, mem_name_wref); 2840} 2841 2842oop InstanceKlass::get_member_name(int index) { 2843 MutexLocker ml(MemberNameTable_lock); 2844 assert(0 <= index && index < idnum_allocated_count(), "index is out of bounds"); 2845 DEBUG_ONLY(No_Safepoint_Verifier nsv); 2846 2847 if (_member_names == NULL) { 2848 return NULL; 2849 } 2850 oop mem_name =_member_names->get_member_name(index); 2851 return mem_name; 2852} 2853 2854// ----------------------------------------------------------------------------------------------------- 2855// Printing 2856 2857#ifndef PRODUCT 2858 2859#define BULLET " - " 2860 2861static const char* state_names[] = { 2862 "allocated", "loaded", "linked", "being_initialized", "fully_initialized", "initialization_error" 2863}; 2864 2865static void print_vtable(intptr_t* start, int len, outputStream* st) { 2866 for (int i = 0; i < len; i++) { 2867 intptr_t e = start[i]; 2868 st->print("%d : " INTPTR_FORMAT, i, e); 2869 if (e != 0 && ((Metadata*)e)->is_metaspace_object()) { 2870 st->print(" "); 2871 ((Metadata*)e)->print_value_on(st); 2872 } 2873 st->cr(); 2874 } 2875} 2876 2877void InstanceKlass::print_on(outputStream* st) const { 2878 assert(is_klass(), "must be klass"); 2879 Klass::print_on(st); 2880 2881 st->print(BULLET"instance size: %d", size_helper()); st->cr(); 2882 st->print(BULLET"klass size: %d", size()); st->cr(); 2883 st->print(BULLET"access: "); access_flags().print_on(st); st->cr(); 2884 st->print(BULLET"state: "); st->print_cr("%s", state_names[_init_state]); 2885 st->print(BULLET"name: "); name()->print_value_on(st); st->cr(); 2886 st->print(BULLET"super: "); super()->print_value_on_maybe_null(st); st->cr(); 2887 st->print(BULLET"sub: "); 2888 Klass* sub = subklass(); 2889 int n; 2890 for (n = 0; sub != NULL; n++, sub = sub->next_sibling()) { 2891 if (n < MaxSubklassPrintSize) { 2892 sub->print_value_on(st); 2893 st->print(" "); 2894 } 2895 } 2896 if (n >= MaxSubklassPrintSize) st->print("(%d more klasses...)", n - MaxSubklassPrintSize); 2897 st->cr(); 2898 2899 if (is_interface()) { 2900 st->print_cr(BULLET"nof implementors: %d", nof_implementors()); 2901 if (nof_implementors() == 1) { 2902 st->print_cr(BULLET"implementor: "); 2903 st->print(" "); 2904 implementor()->print_value_on(st); 2905 st->cr(); 2906 } 2907 } 2908 2909 st->print(BULLET"arrays: "); array_klasses()->print_value_on_maybe_null(st); st->cr(); 2910 st->print(BULLET"methods: "); methods()->print_value_on(st); st->cr(); 2911 if (Verbose || WizardMode) { 2912 Array<Method*>* method_array = methods(); 2913 for (int i = 0; i < method_array->length(); i++) { 2914 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr(); 2915 } 2916 } 2917 st->print(BULLET"method ordering: "); method_ordering()->print_value_on(st); st->cr(); 2918 st->print(BULLET"default_methods: "); default_methods()->print_value_on(st); st->cr(); 2919 if (Verbose && default_methods() != NULL) { 2920 Array<Method*>* method_array = default_methods(); 2921 for (int i = 0; i < method_array->length(); i++) { 2922 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr(); 2923 } 2924 } 2925 if (default_vtable_indices() != NULL) { 2926 st->print(BULLET"default vtable indices: "); default_vtable_indices()->print_value_on(st); st->cr(); 2927 } 2928 st->print(BULLET"local interfaces: "); local_interfaces()->print_value_on(st); st->cr(); 2929 st->print(BULLET"trans. interfaces: "); transitive_interfaces()->print_value_on(st); st->cr(); 2930 st->print(BULLET"constants: "); constants()->print_value_on(st); st->cr(); 2931 if (class_loader_data() != NULL) { 2932 st->print(BULLET"class loader data: "); 2933 class_loader_data()->print_value_on(st); 2934 st->cr(); 2935 } 2936 st->print(BULLET"host class: "); host_klass()->print_value_on_maybe_null(st); st->cr(); 2937 if (source_file_name() != NULL) { 2938 st->print(BULLET"source file: "); 2939 source_file_name()->print_value_on(st); 2940 st->cr(); 2941 } 2942 if (source_debug_extension() != NULL) { 2943 st->print(BULLET"source debug extension: "); 2944 st->print("%s", source_debug_extension()); 2945 st->cr(); 2946 } 2947 st->print(BULLET"class annotations: "); class_annotations()->print_value_on(st); st->cr(); 2948 st->print(BULLET"class type annotations: "); class_type_annotations()->print_value_on(st); st->cr(); 2949 st->print(BULLET"field annotations: "); fields_annotations()->print_value_on(st); st->cr(); 2950 st->print(BULLET"field type annotations: "); fields_type_annotations()->print_value_on(st); st->cr(); 2951 { 2952 bool have_pv = false; 2953 PreviousVersionWalker pvw(Thread::current(), (InstanceKlass*)this); 2954 for (PreviousVersionNode * pv_node = pvw.next_previous_version(); 2955 pv_node != NULL; pv_node = pvw.next_previous_version()) { 2956 if (!have_pv) 2957 st->print(BULLET"previous version: "); 2958 have_pv = true; 2959 pv_node->prev_constant_pool()->print_value_on(st); 2960 } 2961 if (have_pv) st->cr(); 2962 } // pvw is cleaned up 2963 2964 if (generic_signature() != NULL) { 2965 st->print(BULLET"generic signature: "); 2966 generic_signature()->print_value_on(st); 2967 st->cr(); 2968 } 2969 st->print(BULLET"inner classes: "); inner_classes()->print_value_on(st); st->cr(); 2970 st->print(BULLET"java mirror: "); java_mirror()->print_value_on(st); st->cr(); 2971 st->print(BULLET"vtable length %d (start addr: " INTPTR_FORMAT ")", vtable_length(), start_of_vtable()); st->cr(); 2972 if (vtable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_vtable(), vtable_length(), st); 2973 st->print(BULLET"itable length %d (start addr: " INTPTR_FORMAT ")", itable_length(), start_of_itable()); st->cr(); 2974 if (itable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_itable(), itable_length(), st); 2975 st->print_cr(BULLET"---- static fields (%d words):", static_field_size()); 2976 FieldPrinter print_static_field(st); 2977 ((InstanceKlass*)this)->do_local_static_fields(&print_static_field); 2978 st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size()); 2979 FieldPrinter print_nonstatic_field(st); 2980 ((InstanceKlass*)this)->do_nonstatic_fields(&print_nonstatic_field); 2981 2982 st->print(BULLET"non-static oop maps: "); 2983 OopMapBlock* map = start_of_nonstatic_oop_maps(); 2984 OopMapBlock* end_map = map + nonstatic_oop_map_count(); 2985 while (map < end_map) { 2986 st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1)); 2987 map++; 2988 } 2989 st->cr(); 2990} 2991 2992#endif //PRODUCT 2993 2994void InstanceKlass::print_value_on(outputStream* st) const { 2995 assert(is_klass(), "must be klass"); 2996 if (Verbose || WizardMode) access_flags().print_on(st); 2997 name()->print_value_on(st); 2998} 2999 3000#ifndef PRODUCT 3001 3002void FieldPrinter::do_field(fieldDescriptor* fd) { 3003 _st->print(BULLET); 3004 if (_obj == NULL) { 3005 fd->print_on(_st); 3006 _st->cr(); 3007 } else { 3008 fd->print_on_for(_st, _obj); 3009 _st->cr(); 3010 } 3011} 3012 3013 3014void InstanceKlass::oop_print_on(oop obj, outputStream* st) { 3015 Klass::oop_print_on(obj, st); 3016 3017 if (this == SystemDictionary::String_klass()) { 3018 typeArrayOop value = java_lang_String::value(obj); 3019 juint offset = java_lang_String::offset(obj); 3020 juint length = java_lang_String::length(obj); 3021 if (value != NULL && 3022 value->is_typeArray() && 3023 offset <= (juint) value->length() && 3024 offset + length <= (juint) value->length()) { 3025 st->print(BULLET"string: "); 3026 java_lang_String::print(obj, st); 3027 st->cr(); 3028 if (!WizardMode) return; // that is enough 3029 } 3030 } 3031 3032 st->print_cr(BULLET"---- fields (total size %d words):", oop_size(obj)); 3033 FieldPrinter print_field(st, obj); 3034 do_nonstatic_fields(&print_field); 3035 3036 if (this == SystemDictionary::Class_klass()) { 3037 st->print(BULLET"signature: "); 3038 java_lang_Class::print_signature(obj, st); 3039 st->cr(); 3040 Klass* mirrored_klass = java_lang_Class::as_Klass(obj); 3041 st->print(BULLET"fake entry for mirror: "); 3042 mirrored_klass->print_value_on_maybe_null(st); 3043 st->cr(); 3044 Klass* array_klass = java_lang_Class::array_klass(obj); 3045 st->print(BULLET"fake entry for array: "); 3046 array_klass->print_value_on_maybe_null(st); 3047 st->cr(); 3048 st->print_cr(BULLET"fake entry for oop_size: %d", java_lang_Class::oop_size(obj)); 3049 st->print_cr(BULLET"fake entry for static_oop_field_count: %d", java_lang_Class::static_oop_field_count(obj)); 3050 Klass* real_klass = java_lang_Class::as_Klass(obj); 3051 if (real_klass != NULL && real_klass->oop_is_instance()) { 3052 InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field); 3053 } 3054 } else if (this == SystemDictionary::MethodType_klass()) { 3055 st->print(BULLET"signature: "); 3056 java_lang_invoke_MethodType::print_signature(obj, st); 3057 st->cr(); 3058 } 3059} 3060 3061#endif //PRODUCT 3062 3063void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) { 3064 st->print("a "); 3065 name()->print_value_on(st); 3066 obj->print_address_on(st); 3067 if (this == SystemDictionary::String_klass() 3068 && java_lang_String::value(obj) != NULL) { 3069 ResourceMark rm; 3070 int len = java_lang_String::length(obj); 3071 int plen = (len < 24 ? len : 12); 3072 char* str = java_lang_String::as_utf8_string(obj, 0, plen); 3073 st->print(" = \"%s\"", str); 3074 if (len > plen) 3075 st->print("...[%d]", len); 3076 } else if (this == SystemDictionary::Class_klass()) { 3077 Klass* k = java_lang_Class::as_Klass(obj); 3078 st->print(" = "); 3079 if (k != NULL) { 3080 k->print_value_on(st); 3081 } else { 3082 const char* tname = type2name(java_lang_Class::primitive_type(obj)); 3083 st->print("%s", tname ? tname : "type?"); 3084 } 3085 } else if (this == SystemDictionary::MethodType_klass()) { 3086 st->print(" = "); 3087 java_lang_invoke_MethodType::print_signature(obj, st); 3088 } else if (java_lang_boxing_object::is_instance(obj)) { 3089 st->print(" = "); 3090 java_lang_boxing_object::print(obj, st); 3091 } else if (this == SystemDictionary::LambdaForm_klass()) { 3092 oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj); 3093 if (vmentry != NULL) { 3094 st->print(" => "); 3095 vmentry->print_value_on(st); 3096 } 3097 } else if (this == SystemDictionary::MemberName_klass()) { 3098 Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj); 3099 if (vmtarget != NULL) { 3100 st->print(" = "); 3101 vmtarget->print_value_on(st); 3102 } else { 3103 java_lang_invoke_MemberName::clazz(obj)->print_value_on(st); 3104 st->print("."); 3105 java_lang_invoke_MemberName::name(obj)->print_value_on(st); 3106 } 3107 } 3108} 3109 3110const char* InstanceKlass::internal_name() const { 3111 return external_name(); 3112} 3113 3114#if INCLUDE_SERVICES 3115// Size Statistics 3116void InstanceKlass::collect_statistics(KlassSizeStats *sz) const { 3117 Klass::collect_statistics(sz); 3118 3119 sz->_inst_size = HeapWordSize * size_helper(); 3120 sz->_vtab_bytes = HeapWordSize * align_object_offset(vtable_length()); 3121 sz->_itab_bytes = HeapWordSize * align_object_offset(itable_length()); 3122 sz->_nonstatic_oopmap_bytes = HeapWordSize * 3123 ((is_interface() || is_anonymous()) ? 3124 align_object_offset(nonstatic_oop_map_size()) : 3125 nonstatic_oop_map_size()); 3126 3127 int n = 0; 3128 n += (sz->_methods_array_bytes = sz->count_array(methods())); 3129 n += (sz->_method_ordering_bytes = sz->count_array(method_ordering())); 3130 n += (sz->_local_interfaces_bytes = sz->count_array(local_interfaces())); 3131 n += (sz->_transitive_interfaces_bytes = sz->count_array(transitive_interfaces())); 3132 n += (sz->_fields_bytes = sz->count_array(fields())); 3133 n += (sz->_inner_classes_bytes = sz->count_array(inner_classes())); 3134 sz->_ro_bytes += n; 3135 3136 const ConstantPool* cp = constants(); 3137 if (cp) { 3138 cp->collect_statistics(sz); 3139 } 3140 3141 const Annotations* anno = annotations(); 3142 if (anno) { 3143 anno->collect_statistics(sz); 3144 } 3145 3146 const Array<Method*>* methods_array = methods(); 3147 if (methods()) { 3148 for (int i = 0; i < methods_array->length(); i++) { 3149 Method* method = methods_array->at(i); 3150 if (method) { 3151 sz->_method_count ++; 3152 method->collect_statistics(sz); 3153 } 3154 } 3155 } 3156} 3157#endif // INCLUDE_SERVICES 3158 3159// Verification 3160 3161class VerifyFieldClosure: public OopClosure { 3162 protected: 3163 template <class T> void do_oop_work(T* p) { 3164 oop obj = oopDesc::load_decode_heap_oop(p); 3165 if (!obj->is_oop_or_null()) { 3166 tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p, (address)obj); 3167 Universe::print(); 3168 guarantee(false, "boom"); 3169 } 3170 } 3171 public: 3172 virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); } 3173 virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); } 3174}; 3175 3176void InstanceKlass::verify_on(outputStream* st) { 3177#ifndef PRODUCT 3178 // Avoid redundant verifies, this really should be in product. 3179 if (_verify_count == Universe::verify_count()) return; 3180 _verify_count = Universe::verify_count(); 3181#endif 3182 3183 // Verify Klass 3184 Klass::verify_on(st); 3185 3186 // Verify that klass is present in ClassLoaderData 3187 guarantee(class_loader_data()->contains_klass(this), 3188 "this class isn't found in class loader data"); 3189 3190 // Verify vtables 3191 if (is_linked()) { 3192 ResourceMark rm; 3193 // $$$ This used to be done only for m/s collections. Doing it 3194 // always seemed a valid generalization. (DLD -- 6/00) 3195 vtable()->verify(st); 3196 } 3197 3198 // Verify first subklass 3199 if (subklass() != NULL) { 3200 guarantee(subklass()->is_klass(), "should be klass"); 3201 } 3202 3203 // Verify siblings 3204 Klass* super = this->super(); 3205 Klass* sib = next_sibling(); 3206 if (sib != NULL) { 3207 if (sib == this) { 3208 fatal(err_msg("subclass points to itself " PTR_FORMAT, sib)); 3209 } 3210 3211 guarantee(sib->is_klass(), "should be klass"); 3212 guarantee(sib->super() == super, "siblings should have same superklass"); 3213 } 3214 3215 // Verify implementor fields 3216 Klass* im = implementor(); 3217 if (im != NULL) { 3218 guarantee(is_interface(), "only interfaces should have implementor set"); 3219 guarantee(im->is_klass(), "should be klass"); 3220 guarantee(!im->is_interface() || im == this, 3221 "implementors cannot be interfaces"); 3222 } 3223 3224 // Verify local interfaces 3225 if (local_interfaces()) { 3226 Array<Klass*>* local_interfaces = this->local_interfaces(); 3227 for (int j = 0; j < local_interfaces->length(); j++) { 3228 Klass* e = local_interfaces->at(j); 3229 guarantee(e->is_klass() && e->is_interface(), "invalid local interface"); 3230 } 3231 } 3232 3233 // Verify transitive interfaces 3234 if (transitive_interfaces() != NULL) { 3235 Array<Klass*>* transitive_interfaces = this->transitive_interfaces(); 3236 for (int j = 0; j < transitive_interfaces->length(); j++) { 3237 Klass* e = transitive_interfaces->at(j); 3238 guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface"); 3239 } 3240 } 3241 3242 // Verify methods 3243 if (methods() != NULL) { 3244 Array<Method*>* methods = this->methods(); 3245 for (int j = 0; j < methods->length(); j++) { 3246 guarantee(methods->at(j)->is_method(), "non-method in methods array"); 3247 } 3248 for (int j = 0; j < methods->length() - 1; j++) { 3249 Method* m1 = methods->at(j); 3250 Method* m2 = methods->at(j + 1); 3251 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly"); 3252 } 3253 } 3254 3255 // Verify method ordering 3256 if (method_ordering() != NULL) { 3257 Array<int>* method_ordering = this->method_ordering(); 3258 int length = method_ordering->length(); 3259 if (JvmtiExport::can_maintain_original_method_order() || 3260 ((UseSharedSpaces || DumpSharedSpaces) && length != 0)) { 3261 guarantee(length == methods()->length(), "invalid method ordering length"); 3262 jlong sum = 0; 3263 for (int j = 0; j < length; j++) { 3264 int original_index = method_ordering->at(j); 3265 guarantee(original_index >= 0, "invalid method ordering index"); 3266 guarantee(original_index < length, "invalid method ordering index"); 3267 sum += original_index; 3268 } 3269 // Verify sum of indices 0,1,...,length-1 3270 guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum"); 3271 } else { 3272 guarantee(length == 0, "invalid method ordering length"); 3273 } 3274 } 3275 3276 // Verify default methods 3277 if (default_methods() != NULL) { 3278 Array<Method*>* methods = this->default_methods(); 3279 for (int j = 0; j < methods->length(); j++) { 3280 guarantee(methods->at(j)->is_method(), "non-method in methods array"); 3281 } 3282 for (int j = 0; j < methods->length() - 1; j++) { 3283 Method* m1 = methods->at(j); 3284 Method* m2 = methods->at(j + 1); 3285 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly"); 3286 } 3287 } 3288 3289 // Verify JNI static field identifiers 3290 if (jni_ids() != NULL) { 3291 jni_ids()->verify(this); 3292 } 3293 3294 // Verify other fields 3295 if (array_klasses() != NULL) { 3296 guarantee(array_klasses()->is_klass(), "should be klass"); 3297 } 3298 if (constants() != NULL) { 3299 guarantee(constants()->is_constantPool(), "should be constant pool"); 3300 } 3301 const Klass* host = host_klass(); 3302 if (host != NULL) { 3303 guarantee(host->is_klass(), "should be klass"); 3304 } 3305} 3306 3307void InstanceKlass::oop_verify_on(oop obj, outputStream* st) { 3308 Klass::oop_verify_on(obj, st); 3309 VerifyFieldClosure blk; 3310 obj->oop_iterate_no_header(&blk); 3311} 3312 3313 3314// JNIid class for jfieldIDs only 3315// Note to reviewers: 3316// These JNI functions are just moved over to column 1 and not changed 3317// in the compressed oops workspace. 3318JNIid::JNIid(Klass* holder, int offset, JNIid* next) { 3319 _holder = holder; 3320 _offset = offset; 3321 _next = next; 3322 debug_only(_is_static_field_id = false;) 3323} 3324 3325 3326JNIid* JNIid::find(int offset) { 3327 JNIid* current = this; 3328 while (current != NULL) { 3329 if (current->offset() == offset) return current; 3330 current = current->next(); 3331 } 3332 return NULL; 3333} 3334 3335void JNIid::deallocate(JNIid* current) { 3336 while (current != NULL) { 3337 JNIid* next = current->next(); 3338 delete current; 3339 current = next; 3340 } 3341} 3342 3343 3344void JNIid::verify(Klass* holder) { 3345 int first_field_offset = InstanceMirrorKlass::offset_of_static_fields(); 3346 int end_field_offset; 3347 end_field_offset = first_field_offset + (InstanceKlass::cast(holder)->static_field_size() * wordSize); 3348 3349 JNIid* current = this; 3350 while (current != NULL) { 3351 guarantee(current->holder() == holder, "Invalid klass in JNIid"); 3352#ifdef ASSERT 3353 int o = current->offset(); 3354 if (current->is_static_field_id()) { 3355 guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid"); 3356 } 3357#endif 3358 current = current->next(); 3359 } 3360} 3361 3362 3363#ifdef ASSERT 3364void InstanceKlass::set_init_state(ClassState state) { 3365 bool good_state = is_shared() ? (_init_state <= state) 3366 : (_init_state < state); 3367 assert(good_state || state == allocated, "illegal state transition"); 3368 _init_state = (u1)state; 3369} 3370#endif 3371 3372 3373// RedefineClasses() support for previous versions: 3374 3375// Purge previous versions 3376static void purge_previous_versions_internal(InstanceKlass* ik, int emcp_method_count) { 3377 if (ik->previous_versions() != NULL) { 3378 // This klass has previous versions so see what we can cleanup 3379 // while it is safe to do so. 3380 3381 int deleted_count = 0; // leave debugging breadcrumbs 3382 int live_count = 0; 3383 ClassLoaderData* loader_data = ik->class_loader_data() == NULL ? 3384 ClassLoaderData::the_null_class_loader_data() : 3385 ik->class_loader_data(); 3386 3387 // RC_TRACE macro has an embedded ResourceMark 3388 RC_TRACE(0x00000200, ("purge: %s: previous version length=%d", 3389 ik->external_name(), ik->previous_versions()->length())); 3390 3391 for (int i = ik->previous_versions()->length() - 1; i >= 0; i--) { 3392 // check the previous versions array 3393 PreviousVersionNode * pv_node = ik->previous_versions()->at(i); 3394 ConstantPool* cp_ref = pv_node->prev_constant_pool(); 3395 assert(cp_ref != NULL, "cp ref was unexpectedly cleared"); 3396 3397 ConstantPool* pvcp = cp_ref; 3398 if (!pvcp->on_stack()) { 3399 // If the constant pool isn't on stack, none of the methods 3400 // are executing. Delete all the methods, the constant pool and 3401 // and this previous version node. 3402 GrowableArray<Method*>* method_refs = pv_node->prev_EMCP_methods(); 3403 if (method_refs != NULL) { 3404 for (int j = method_refs->length() - 1; j >= 0; j--) { 3405 Method* method = method_refs->at(j); 3406 assert(method != NULL, "method ref was unexpectedly cleared"); 3407 method_refs->remove_at(j); 3408 // method will be freed with associated class. 3409 } 3410 } 3411 // Remove the constant pool 3412 delete pv_node; 3413 // Since we are traversing the array backwards, we don't have to 3414 // do anything special with the index. 3415 ik->previous_versions()->remove_at(i); 3416 deleted_count++; 3417 continue; 3418 } else { 3419 RC_TRACE(0x00000200, ("purge: previous version @%d is alive", i)); 3420 assert(pvcp->pool_holder() != NULL, "Constant pool with no holder"); 3421 guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack"); 3422 live_count++; 3423 } 3424 3425 // At least one method is live in this previous version, clean out 3426 // the others or mark them as obsolete. 3427 GrowableArray<Method*>* method_refs = pv_node->prev_EMCP_methods(); 3428 if (method_refs != NULL) { 3429 RC_TRACE(0x00000200, ("purge: previous methods length=%d", 3430 method_refs->length())); 3431 for (int j = method_refs->length() - 1; j >= 0; j--) { 3432 Method* method = method_refs->at(j); 3433 assert(method != NULL, "method ref was unexpectedly cleared"); 3434 3435 // Remove the emcp method if it's not executing 3436 // If it's been made obsolete by a redefinition of a non-emcp 3437 // method, mark it as obsolete but leave it to clean up later. 3438 if (!method->on_stack()) { 3439 method_refs->remove_at(j); 3440 } else if (emcp_method_count == 0) { 3441 method->set_is_obsolete(); 3442 } else { 3443 // RC_TRACE macro has an embedded ResourceMark 3444 RC_TRACE(0x00000200, 3445 ("purge: %s(%s): prev method @%d in version @%d is alive", 3446 method->name()->as_C_string(), 3447 method->signature()->as_C_string(), j, i)); 3448 if (method->method_data() != NULL) { 3449 // Clean out any weak method links 3450 method->method_data()->clean_weak_method_links(); 3451 } 3452 } 3453 } 3454 } 3455 } 3456 assert(ik->previous_versions()->length() == live_count, "sanity check"); 3457 RC_TRACE(0x00000200, 3458 ("purge: previous version stats: live=%d, deleted=%d", live_count, 3459 deleted_count)); 3460 } 3461 3462 Array<Method*>* methods = ik->methods(); 3463 int num_methods = methods->length(); 3464 for (int index2 = 0; index2 < num_methods; ++index2) { 3465 if (methods->at(index2)->method_data() != NULL) { 3466 methods->at(index2)->method_data()->clean_weak_method_links(); 3467 } 3468 } 3469} 3470 3471// External interface for use during class unloading. 3472void InstanceKlass::purge_previous_versions(InstanceKlass* ik) { 3473 // Call with >0 emcp methods since they are not currently being redefined. 3474 purge_previous_versions_internal(ik, 1); 3475} 3476 3477 3478// Potentially add an information node that contains pointers to the 3479// interesting parts of the previous version of the_class. 3480// This is also where we clean out any unused references. 3481// Note that while we delete nodes from the _previous_versions 3482// array, we never delete the array itself until the klass is 3483// unloaded. The has_been_redefined() query depends on that fact. 3484// 3485void InstanceKlass::add_previous_version(instanceKlassHandle ikh, 3486 BitMap* emcp_methods, int emcp_method_count) { 3487 assert(Thread::current()->is_VM_thread(), 3488 "only VMThread can add previous versions"); 3489 3490 if (_previous_versions == NULL) { 3491 // This is the first previous version so make some space. 3492 // Start with 2 elements under the assumption that the class 3493 // won't be redefined much. 3494 _previous_versions = new (ResourceObj::C_HEAP, mtClass) 3495 GrowableArray<PreviousVersionNode *>(2, true); 3496 } 3497 3498 ConstantPool* cp_ref = ikh->constants(); 3499 3500 // RC_TRACE macro has an embedded ResourceMark 3501 RC_TRACE(0x00000400, ("adding previous version ref for %s @%d, EMCP_cnt=%d " 3502 "on_stack=%d", 3503 ikh->external_name(), _previous_versions->length(), emcp_method_count, 3504 cp_ref->on_stack())); 3505 3506 // If the constant pool for this previous version of the class 3507 // is not marked as being on the stack, then none of the methods 3508 // in this previous version of the class are on the stack so 3509 // we don't need to create a new PreviousVersionNode. However, 3510 // we still need to examine older previous versions below. 3511 Array<Method*>* old_methods = ikh->methods(); 3512 3513 if (cp_ref->on_stack()) { 3514 PreviousVersionNode * pv_node = NULL; 3515 if (emcp_method_count == 0) { 3516 // non-shared ConstantPool gets a reference 3517 pv_node = new PreviousVersionNode(cp_ref, NULL); 3518 RC_TRACE(0x00000400, 3519 ("add: all methods are obsolete; flushing any EMCP refs")); 3520 } else { 3521 int local_count = 0; 3522 GrowableArray<Method*>* method_refs = new (ResourceObj::C_HEAP, mtClass) 3523 GrowableArray<Method*>(emcp_method_count, true); 3524 for (int i = 0; i < old_methods->length(); i++) { 3525 if (emcp_methods->at(i)) { 3526 // this old method is EMCP. Save it only if it's on the stack 3527 Method* old_method = old_methods->at(i); 3528 if (old_method->on_stack()) { 3529 method_refs->append(old_method); 3530 } 3531 if (++local_count >= emcp_method_count) { 3532 // no more EMCP methods so bail out now 3533 break; 3534 } 3535 } 3536 } 3537 // non-shared ConstantPool gets a reference 3538 pv_node = new PreviousVersionNode(cp_ref, method_refs); 3539 } 3540 // append new previous version. 3541 _previous_versions->append(pv_node); 3542 } 3543 3544 // Since the caller is the VMThread and we are at a safepoint, this 3545 // is a good time to clear out unused references. 3546 3547 RC_TRACE(0x00000400, ("add: previous version length=%d", 3548 _previous_versions->length())); 3549 3550 // Purge previous versions not executing on the stack 3551 purge_previous_versions_internal(this, emcp_method_count); 3552 3553 int obsolete_method_count = old_methods->length() - emcp_method_count; 3554 3555 if (emcp_method_count != 0 && obsolete_method_count != 0 && 3556 _previous_versions->length() > 0) { 3557 // We have a mix of obsolete and EMCP methods so we have to 3558 // clear out any matching EMCP method entries the hard way. 3559 int local_count = 0; 3560 for (int i = 0; i < old_methods->length(); i++) { 3561 if (!emcp_methods->at(i)) { 3562 // only obsolete methods are interesting 3563 Method* old_method = old_methods->at(i); 3564 Symbol* m_name = old_method->name(); 3565 Symbol* m_signature = old_method->signature(); 3566 3567 // we might not have added the last entry 3568 for (int j = _previous_versions->length() - 1; j >= 0; j--) { 3569 // check the previous versions array for non executing obsolete methods 3570 PreviousVersionNode * pv_node = _previous_versions->at(j); 3571 3572 GrowableArray<Method*>* method_refs = pv_node->prev_EMCP_methods(); 3573 if (method_refs == NULL) { 3574 // We have run into a PreviousVersion generation where 3575 // all methods were made obsolete during that generation's 3576 // RedefineClasses() operation. At the time of that 3577 // operation, all EMCP methods were flushed so we don't 3578 // have to go back any further. 3579 // 3580 // A NULL method_refs is different than an empty method_refs. 3581 // We cannot infer any optimizations about older generations 3582 // from an empty method_refs for the current generation. 3583 break; 3584 } 3585 3586 for (int k = method_refs->length() - 1; k >= 0; k--) { 3587 Method* method = method_refs->at(k); 3588 3589 if (!method->is_obsolete() && 3590 method->name() == m_name && 3591 method->signature() == m_signature) { 3592 // The current RedefineClasses() call has made all EMCP 3593 // versions of this method obsolete so mark it as obsolete 3594 // and remove the reference. 3595 RC_TRACE(0x00000400, 3596 ("add: %s(%s): flush obsolete method @%d in version @%d", 3597 m_name->as_C_string(), m_signature->as_C_string(), k, j)); 3598 3599 method->set_is_obsolete(); 3600 // Leave obsolete methods on the previous version list to 3601 // clean up later. 3602 break; 3603 } 3604 } 3605 3606 // The previous loop may not find a matching EMCP method, but 3607 // that doesn't mean that we can optimize and not go any 3608 // further back in the PreviousVersion generations. The EMCP 3609 // method for this generation could have already been deleted, 3610 // but there still may be an older EMCP method that has not 3611 // been deleted. 3612 } 3613 3614 if (++local_count >= obsolete_method_count) { 3615 // no more obsolete methods so bail out now 3616 break; 3617 } 3618 } 3619 } 3620 } 3621} // end add_previous_version() 3622 3623 3624// Determine if InstanceKlass has a previous version. 3625bool InstanceKlass::has_previous_version() const { 3626 return (_previous_versions != NULL && _previous_versions->length() > 0); 3627} // end has_previous_version() 3628 3629 3630Method* InstanceKlass::method_with_idnum(int idnum) { 3631 Method* m = NULL; 3632 if (idnum < methods()->length()) { 3633 m = methods()->at(idnum); 3634 } 3635 if (m == NULL || m->method_idnum() != idnum) { 3636 for (int index = 0; index < methods()->length(); ++index) { 3637 m = methods()->at(index); 3638 if (m->method_idnum() == idnum) { 3639 return m; 3640 } 3641 } 3642 // None found, return null for the caller to handle. 3643 return NULL; 3644 } 3645 return m; 3646} 3647 3648jint InstanceKlass::get_cached_class_file_len() { 3649 return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file); 3650} 3651 3652unsigned char * InstanceKlass::get_cached_class_file_bytes() { 3653 return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file); 3654} 3655 3656 3657// Construct a PreviousVersionNode entry for the array hung off 3658// the InstanceKlass. 3659PreviousVersionNode::PreviousVersionNode(ConstantPool* prev_constant_pool, 3660 GrowableArray<Method*>* prev_EMCP_methods) { 3661 3662 _prev_constant_pool = prev_constant_pool; 3663 _prev_EMCP_methods = prev_EMCP_methods; 3664} 3665 3666 3667// Destroy a PreviousVersionNode 3668PreviousVersionNode::~PreviousVersionNode() { 3669 if (_prev_constant_pool != NULL) { 3670 _prev_constant_pool = NULL; 3671 } 3672 3673 if (_prev_EMCP_methods != NULL) { 3674 delete _prev_EMCP_methods; 3675 } 3676} 3677 3678// Construct a helper for walking the previous versions array 3679PreviousVersionWalker::PreviousVersionWalker(Thread* thread, InstanceKlass *ik) { 3680 _thread = thread; 3681 _previous_versions = ik->previous_versions(); 3682 _current_index = 0; 3683 _current_p = NULL; 3684 _current_constant_pool_handle = constantPoolHandle(thread, ik->constants()); 3685} 3686 3687 3688// Return the interesting information for the next previous version 3689// of the klass. Returns NULL if there are no more previous versions. 3690PreviousVersionNode* PreviousVersionWalker::next_previous_version() { 3691 if (_previous_versions == NULL) { 3692 // no previous versions so nothing to return 3693 return NULL; 3694 } 3695 3696 _current_p = NULL; // reset to NULL 3697 _current_constant_pool_handle = NULL; 3698 3699 int length = _previous_versions->length(); 3700 3701 while (_current_index < length) { 3702 PreviousVersionNode * pv_node = _previous_versions->at(_current_index++); 3703 3704 // Save a handle to the constant pool for this previous version, 3705 // which keeps all the methods from being deallocated. 3706 _current_constant_pool_handle = constantPoolHandle(_thread, pv_node->prev_constant_pool()); 3707 _current_p = pv_node; 3708 return pv_node; 3709 } 3710 3711 return NULL; 3712} // end next_previous_version() 3713