1 /* 2 * Copyright (c) 1997, 2015, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25 #include "precompiled.hpp" 26 #include "classfile/javaClasses.hpp" 27 #include "classfile/systemDictionary.hpp" 28 #include "classfile/verifier.hpp" 29 #include "classfile/vmSymbols.hpp" 30 #include "compiler/compileBroker.hpp" 31 #include "gc_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/iterator.inline.hpp" 39 #include "memory/metadataFactory.hpp" 40 #include "memory/oopFactory.hpp" 41 #include "memory/specialized_oop_closures.hpp" 42 #include "oops/fieldStreams.hpp" 43 #include "oops/instanceClassLoaderKlass.hpp" 44 #include "oops/instanceKlass.hpp" 45 #include "oops/instanceMirrorKlass.hpp" 46 #include "oops/instanceOop.hpp" 47 #include "oops/klass.inline.hpp" 48 #include "oops/method.hpp" 49 #include "oops/oop.inline.hpp" 50 #include "oops/symbol.hpp" 51 #include "prims/jvmtiExport.hpp" 52 #include "prims/jvmtiRedefineClassesTrace.hpp" 53 #include "prims/jvmtiRedefineClasses.hpp" 54 #include "prims/jvmtiThreadState.hpp" 55 #include "prims/methodComparator.hpp" 56 #include "runtime/atomic.inline.hpp" 57 #include "runtime/fieldDescriptor.hpp" 58 #include "runtime/handles.inline.hpp" 59 #include "runtime/javaCalls.hpp" 60 #include "runtime/mutexLocker.hpp" 61 #include "runtime/orderAccess.inline.hpp" 62 #include "runtime/thread.inline.hpp" 63 #include "services/classLoadingService.hpp" 64 #include "services/threadService.hpp" 65 #include "utilities/dtrace.hpp" 66 #include "utilities/macros.hpp" 67 #if INCLUDE_ALL_GCS 68 #include "gc_implementation/concurrentMarkSweep/cmsOopClosures.inline.hpp" 69 #include "gc_implementation/g1/g1CollectedHeap.inline.hpp" 70 #include "gc_implementation/g1/g1OopClosures.inline.hpp" 71 #include "gc_implementation/g1/g1RemSet.inline.hpp" 72 #include "gc_implementation/g1/heapRegionManager.inline.hpp" 73 #include "gc_implementation/parNew/parOopClosures.inline.hpp" 74 #include "gc_implementation/parallelScavenge/parallelScavengeHeap.inline.hpp" 75 #include "gc_implementation/parallelScavenge/psPromotionManager.inline.hpp" 76 #include "gc_implementation/parallelScavenge/psScavenge.inline.hpp" 77 #endif // INCLUDE_ALL_GCS 78 #ifdef COMPILER1 79 #include "c1/c1_Compiler.hpp" 80 #endif 81 82 PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC 83 84 #ifdef DTRACE_ENABLED 85 86 87 #define HOTSPOT_CLASS_INITIALIZATION_required HOTSPOT_CLASS_INITIALIZATION_REQUIRED 88 #define HOTSPOT_CLASS_INITIALIZATION_recursive HOTSPOT_CLASS_INITIALIZATION_RECURSIVE 89 #define HOTSPOT_CLASS_INITIALIZATION_concurrent HOTSPOT_CLASS_INITIALIZATION_CONCURRENT 90 #define HOTSPOT_CLASS_INITIALIZATION_erroneous HOTSPOT_CLASS_INITIALIZATION_ERRONEOUS 91 #define HOTSPOT_CLASS_INITIALIZATION_super__failed HOTSPOT_CLASS_INITIALIZATION_SUPER_FAILED 92 #define HOTSPOT_CLASS_INITIALIZATION_clinit HOTSPOT_CLASS_INITIALIZATION_CLINIT 93 #define HOTSPOT_CLASS_INITIALIZATION_error HOTSPOT_CLASS_INITIALIZATION_ERROR 94 #define HOTSPOT_CLASS_INITIALIZATION_end HOTSPOT_CLASS_INITIALIZATION_END 95 #define DTRACE_CLASSINIT_PROBE(type, clss, thread_type) \ 96 { \ 97 char* data = NULL; \ 98 int len = 0; \ 99 Symbol* name = (clss)->name(); \ 100 if (name != NULL) { \ 101 data = (char*)name->bytes(); \ 102 len = name->utf8_length(); \ 103 } \ 104 HOTSPOT_CLASS_INITIALIZATION_##type( \ 105 data, len, (clss)->class_loader(), thread_type); \ 106 } 107 108 #define DTRACE_CLASSINIT_PROBE_WAIT(type, clss, thread_type, wait) \ 109 { \ 110 char* data = NULL; \ 111 int len = 0; \ 112 Symbol* name = (clss)->name(); \ 113 if (name != NULL) { \ 114 data = (char*)name->bytes(); \ 115 len = name->utf8_length(); \ 116 } \ 117 HOTSPOT_CLASS_INITIALIZATION_##type( \ 118 data, len, (clss)->class_loader(), thread_type, wait); \ 119 } 120 121 #else // ndef DTRACE_ENABLED 122 123 #define DTRACE_CLASSINIT_PROBE(type, clss, thread_type) 124 #define DTRACE_CLASSINIT_PROBE_WAIT(type, clss, thread_type, wait) 125 126 #endif // ndef DTRACE_ENABLED 127 128 volatile int InstanceKlass::_total_instanceKlass_count = 0; 129 130 InstanceKlass* InstanceKlass::allocate_instance_klass( 131 ClassLoaderData* loader_data, 132 int vtable_len, 133 int itable_len, 134 int static_field_size, 135 int nonstatic_oop_map_size, 136 ReferenceType rt, 137 AccessFlags access_flags, 138 Symbol* name, 139 Klass* super_klass, 140 bool is_anonymous, 141 TRAPS) { 142 143 int size = InstanceKlass::size(vtable_len, itable_len, nonstatic_oop_map_size, 144 access_flags.is_interface(), is_anonymous); 145 146 // Allocation 147 InstanceKlass* ik; 148 if (rt == REF_NONE) { 149 if (name == vmSymbols::java_lang_Class()) { 150 ik = new (loader_data, size, THREAD) InstanceMirrorKlass( 151 vtable_len, itable_len, static_field_size, nonstatic_oop_map_size, rt, 152 access_flags, is_anonymous); 153 } else if (name == vmSymbols::java_lang_ClassLoader() || 154 (SystemDictionary::ClassLoader_klass_loaded() && 155 super_klass != NULL && 156 super_klass->is_subtype_of(SystemDictionary::ClassLoader_klass()))) { 157 ik = new (loader_data, size, THREAD) InstanceClassLoaderKlass( 158 vtable_len, itable_len, static_field_size, nonstatic_oop_map_size, rt, 159 access_flags, is_anonymous); 160 } else { 161 // normal class 162 ik = new (loader_data, size, THREAD) InstanceKlass( 163 vtable_len, itable_len, static_field_size, nonstatic_oop_map_size, rt, 164 access_flags, is_anonymous); 165 } 166 } else { 167 // reference klass 168 ik = new (loader_data, size, THREAD) InstanceRefKlass( 169 vtable_len, itable_len, static_field_size, nonstatic_oop_map_size, rt, 170 access_flags, is_anonymous); 171 } 172 173 // Check for pending exception before adding to the loader data and incrementing 174 // class count. Can get OOM here. 175 if (HAS_PENDING_EXCEPTION) { 176 return NULL; 177 } 178 179 // Add all classes to our internal class loader list here, 180 // including classes in the bootstrap (NULL) class loader. 181 loader_data->add_class(ik); 182 183 Atomic::inc(&_total_instanceKlass_count); 184 return ik; 185 } 186 187 188 // copy method ordering from resource area to Metaspace 189 void InstanceKlass::copy_method_ordering(intArray* m, TRAPS) { 190 if (m != NULL) { 191 // allocate a new array and copy contents (memcpy?) 192 _method_ordering = MetadataFactory::new_array<int>(class_loader_data(), m->length(), CHECK); 193 for (int i = 0; i < m->length(); i++) { 194 _method_ordering->at_put(i, m->at(i)); 195 } 196 } else { 197 _method_ordering = Universe::the_empty_int_array(); 198 } 199 } 200 201 // create a new array of vtable_indices for default methods 202 Array<int>* InstanceKlass::create_new_default_vtable_indices(int len, TRAPS) { 203 Array<int>* vtable_indices = MetadataFactory::new_array<int>(class_loader_data(), len, CHECK_NULL); 204 assert(default_vtable_indices() == NULL, "only create once"); 205 set_default_vtable_indices(vtable_indices); 206 return vtable_indices; 207 } 208 209 InstanceKlass::InstanceKlass(int vtable_len, 210 int itable_len, 211 int static_field_size, 212 int nonstatic_oop_map_size, 213 ReferenceType rt, 214 AccessFlags access_flags, 215 bool is_anonymous) { 216 No_Safepoint_Verifier no_safepoint; // until k becomes parsable 217 218 int iksize = InstanceKlass::size(vtable_len, itable_len, nonstatic_oop_map_size, 219 access_flags.is_interface(), is_anonymous); 220 221 set_vtable_length(vtable_len); 222 set_itable_length(itable_len); 223 set_static_field_size(static_field_size); 224 set_nonstatic_oop_map_size(nonstatic_oop_map_size); 225 set_access_flags(access_flags); 226 _misc_flags = 0; // initialize to zero 227 set_is_anonymous(is_anonymous); 228 assert(size() == iksize, "wrong size for object"); 229 230 set_array_klasses(NULL); 231 set_methods(NULL); 232 set_method_ordering(NULL); 233 set_default_methods(NULL); 234 set_default_vtable_indices(NULL); 235 set_local_interfaces(NULL); 236 set_transitive_interfaces(NULL); 237 init_implementor(); 238 set_fields(NULL, 0); 239 set_constants(NULL); 240 set_class_loader_data(NULL); 241 set_source_file_name_index(0); 242 set_source_debug_extension(NULL, 0); 243 set_array_name(NULL); 244 set_inner_classes(NULL); 245 set_static_oop_field_count(0); 246 set_nonstatic_field_size(0); 247 set_is_marked_dependent(false); 248 set_has_unloaded_dependent(false); 249 set_init_state(InstanceKlass::allocated); 250 set_init_thread(NULL); 251 set_reference_type(rt); 252 set_oop_map_cache(NULL); 253 set_jni_ids(NULL); 254 set_osr_nmethods_head(NULL); 255 set_breakpoints(NULL); 256 init_previous_versions(); 257 set_generic_signature_index(0); 258 release_set_methods_jmethod_ids(NULL); 259 set_annotations(NULL); 260 set_jvmti_cached_class_field_map(NULL); 261 set_initial_method_idnum(0); 262 _dependencies = NULL; 263 set_jvmti_cached_class_field_map(NULL); 264 set_cached_class_file(NULL); 265 set_initial_method_idnum(0); 266 set_minor_version(0); 267 set_major_version(0); 268 NOT_PRODUCT(_verify_count = 0;) 269 270 // initialize the non-header words to zero 271 intptr_t* p = (intptr_t*)this; 272 for (int index = InstanceKlass::header_size(); index < iksize; index++) { 273 p[index] = NULL_WORD; 274 } 275 276 // Set temporary value until parseClassFile updates it with the real instance 277 // size. 278 set_layout_helper(Klass::instance_layout_helper(0, true)); 279 } 280 281 282 void InstanceKlass::deallocate_methods(ClassLoaderData* loader_data, 283 Array<Method*>* methods) { 284 if (methods != NULL && methods != Universe::the_empty_method_array() && 285 !methods->is_shared()) { 286 for (int i = 0; i < methods->length(); i++) { 287 Method* method = methods->at(i); 288 if (method == NULL) continue; // maybe null if error processing 289 // Only want to delete methods that are not executing for RedefineClasses. 290 // The previous version will point to them so they're not totally dangling 291 assert (!method->on_stack(), "shouldn't be called with methods on stack"); 292 MetadataFactory::free_metadata(loader_data, method); 293 } 294 MetadataFactory::free_array<Method*>(loader_data, methods); 295 } 296 } 297 298 void InstanceKlass::deallocate_interfaces(ClassLoaderData* loader_data, 299 Klass* super_klass, 300 Array<Klass*>* local_interfaces, 301 Array<Klass*>* transitive_interfaces) { 302 // Only deallocate transitive interfaces if not empty, same as super class 303 // or same as local interfaces. See code in parseClassFile. 304 Array<Klass*>* ti = transitive_interfaces; 305 if (ti != Universe::the_empty_klass_array() && ti != local_interfaces) { 306 // check that the interfaces don't come from super class 307 Array<Klass*>* sti = (super_klass == NULL) ? NULL : 308 InstanceKlass::cast(super_klass)->transitive_interfaces(); 309 if (ti != sti && ti != NULL && !ti->is_shared()) { 310 MetadataFactory::free_array<Klass*>(loader_data, ti); 311 } 312 } 313 314 // local interfaces can be empty 315 if (local_interfaces != Universe::the_empty_klass_array() && 316 local_interfaces != NULL && !local_interfaces->is_shared()) { 317 MetadataFactory::free_array<Klass*>(loader_data, local_interfaces); 318 } 319 } 320 321 // This function deallocates the metadata and C heap pointers that the 322 // InstanceKlass points to. 323 void InstanceKlass::deallocate_contents(ClassLoaderData* loader_data) { 324 325 // Orphan the mirror first, CMS thinks it's still live. 326 if (java_mirror() != NULL) { 327 java_lang_Class::set_klass(java_mirror(), NULL); 328 } 329 330 // Need to take this class off the class loader data list. 331 loader_data->remove_class(this); 332 333 // The array_klass for this class is created later, after error handling. 334 // For class redefinition, we keep the original class so this scratch class 335 // doesn't have an array class. Either way, assert that there is nothing 336 // to deallocate. 337 assert(array_klasses() == NULL, "array classes shouldn't be created for this class yet"); 338 339 // Release C heap allocated data that this might point to, which includes 340 // reference counting symbol names. 341 release_C_heap_structures(); 342 343 deallocate_methods(loader_data, methods()); 344 set_methods(NULL); 345 346 if (method_ordering() != NULL && 347 method_ordering() != Universe::the_empty_int_array() && 348 !method_ordering()->is_shared()) { 349 MetadataFactory::free_array<int>(loader_data, method_ordering()); 350 } 351 set_method_ordering(NULL); 352 353 // default methods can be empty 354 if (default_methods() != NULL && 355 default_methods() != Universe::the_empty_method_array() && 356 !default_methods()->is_shared()) { 357 MetadataFactory::free_array<Method*>(loader_data, default_methods()); 358 } 359 // Do NOT deallocate the default methods, they are owned by superinterfaces. 360 set_default_methods(NULL); 361 362 // default methods vtable indices can be empty 363 if (default_vtable_indices() != NULL && 364 !default_vtable_indices()->is_shared()) { 365 MetadataFactory::free_array<int>(loader_data, default_vtable_indices()); 366 } 367 set_default_vtable_indices(NULL); 368 369 370 // This array is in Klass, but remove it with the InstanceKlass since 371 // this place would be the only caller and it can share memory with transitive 372 // interfaces. 373 if (secondary_supers() != NULL && 374 secondary_supers() != Universe::the_empty_klass_array() && 375 secondary_supers() != transitive_interfaces() && 376 !secondary_supers()->is_shared()) { 377 MetadataFactory::free_array<Klass*>(loader_data, secondary_supers()); 378 } 379 set_secondary_supers(NULL); 380 381 deallocate_interfaces(loader_data, super(), local_interfaces(), transitive_interfaces()); 382 set_transitive_interfaces(NULL); 383 set_local_interfaces(NULL); 384 385 if (fields() != NULL && !fields()->is_shared()) { 386 MetadataFactory::free_array<jushort>(loader_data, fields()); 387 } 388 set_fields(NULL, 0); 389 390 // If a method from a redefined class is using this constant pool, don't 391 // delete it, yet. The new class's previous version will point to this. 392 if (constants() != NULL) { 393 assert (!constants()->on_stack(), "shouldn't be called if anything is onstack"); 394 if (!constants()->is_shared()) { 395 MetadataFactory::free_metadata(loader_data, constants()); 396 } 397 set_constants(NULL); 398 } 399 400 if (inner_classes() != NULL && 401 inner_classes() != Universe::the_empty_short_array() && 402 !inner_classes()->is_shared()) { 403 MetadataFactory::free_array<jushort>(loader_data, inner_classes()); 404 } 405 set_inner_classes(NULL); 406 407 // We should deallocate the Annotations instance if it's not in shared spaces. 408 if (annotations() != NULL && !annotations()->is_shared()) { 409 MetadataFactory::free_metadata(loader_data, annotations()); 410 } 411 set_annotations(NULL); 412 } 413 414 bool InstanceKlass::should_be_initialized() const { 415 return !is_initialized(); 416 } 417 418 klassVtable* InstanceKlass::vtable() const { 419 return new klassVtable(this, start_of_vtable(), vtable_length() / vtableEntry::size()); 420 } 421 422 klassItable* InstanceKlass::itable() const { 423 return new klassItable(instanceKlassHandle(this)); 424 } 425 426 void InstanceKlass::eager_initialize(Thread *thread) { 427 if (!EagerInitialization) return; 428 429 if (this->is_not_initialized()) { 430 // abort if the the class has a class initializer 431 if (this->class_initializer() != NULL) return; 432 433 // abort if it is java.lang.Object (initialization is handled in genesis) 434 Klass* super = this->super(); 435 if (super == NULL) return; 436 437 // abort if the super class should be initialized 438 if (!InstanceKlass::cast(super)->is_initialized()) return; 439 440 // call body to expose the this pointer 441 instanceKlassHandle this_k(thread, this); 442 eager_initialize_impl(this_k); 443 } 444 } 445 446 // JVMTI spec thinks there are signers and protection domain in the 447 // instanceKlass. These accessors pretend these fields are there. 448 // The hprof specification also thinks these fields are in InstanceKlass. 449 oop InstanceKlass::protection_domain() const { 450 // return the protection_domain from the mirror 451 return java_lang_Class::protection_domain(java_mirror()); 452 } 453 454 // To remove these from requires an incompatible change and CCC request. 455 objArrayOop InstanceKlass::signers() const { 456 // return the signers from the mirror 457 return java_lang_Class::signers(java_mirror()); 458 } 459 460 oop InstanceKlass::init_lock() const { 461 // return the init lock from the mirror 462 oop lock = java_lang_Class::init_lock(java_mirror()); 463 // Prevent reordering with any access of initialization state 464 OrderAccess::loadload(); 465 assert((oop)lock != NULL || !is_not_initialized(), // initialized or in_error state 466 "only fully initialized state can have a null lock"); 467 return lock; 468 } 469 470 // Set the initialization lock to null so the object can be GC'ed. Any racing 471 // threads to get this lock will see a null lock and will not lock. 472 // That's okay because they all check for initialized state after getting 473 // the lock and return. 474 void InstanceKlass::fence_and_clear_init_lock() { 475 // make sure previous stores are all done, notably the init_state. 476 OrderAccess::storestore(); 477 java_lang_Class::set_init_lock(java_mirror(), NULL); 478 assert(!is_not_initialized(), "class must be initialized now"); 479 } 480 481 void InstanceKlass::eager_initialize_impl(instanceKlassHandle this_k) { 482 EXCEPTION_MARK; 483 oop init_lock = this_k->init_lock(); 484 ObjectLocker ol(init_lock, THREAD, init_lock != NULL); 485 486 // abort if someone beat us to the initialization 487 if (!this_k->is_not_initialized()) return; // note: not equivalent to is_initialized() 488 489 ClassState old_state = this_k->init_state(); 490 link_class_impl(this_k, true, THREAD); 491 if (HAS_PENDING_EXCEPTION) { 492 CLEAR_PENDING_EXCEPTION; 493 // Abort if linking the class throws an exception. 494 495 // Use a test to avoid redundantly resetting the state if there's 496 // no change. Set_init_state() asserts that state changes make 497 // progress, whereas here we might just be spinning in place. 498 if( old_state != this_k->_init_state ) 499 this_k->set_init_state (old_state); 500 } else { 501 // linking successfull, mark class as initialized 502 this_k->set_init_state (fully_initialized); 503 this_k->fence_and_clear_init_lock(); 504 // trace 505 if (TraceClassInitialization) { 506 ResourceMark rm(THREAD); 507 tty->print_cr("[Initialized %s without side effects]", this_k->external_name()); 508 } 509 } 510 } 511 512 513 // See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization 514 // process. The step comments refers to the procedure described in that section. 515 // Note: implementation moved to static method to expose the this pointer. 516 void InstanceKlass::initialize(TRAPS) { 517 if (this->should_be_initialized()) { 518 HandleMark hm(THREAD); 519 instanceKlassHandle this_k(THREAD, this); 520 initialize_impl(this_k, CHECK); 521 // Note: at this point the class may be initialized 522 // OR it may be in the state of being initialized 523 // in case of recursive initialization! 524 } else { 525 assert(is_initialized(), "sanity check"); 526 } 527 } 528 529 530 bool InstanceKlass::verify_code( 531 instanceKlassHandle this_k, bool throw_verifyerror, TRAPS) { 532 // 1) Verify the bytecodes 533 Verifier::Mode mode = 534 throw_verifyerror ? Verifier::ThrowException : Verifier::NoException; 535 return Verifier::verify(this_k, mode, this_k->should_verify_class(), THREAD); 536 } 537 538 539 // Used exclusively by the shared spaces dump mechanism to prevent 540 // classes mapped into the shared regions in new VMs from appearing linked. 541 542 void InstanceKlass::unlink_class() { 543 assert(is_linked(), "must be linked"); 544 _init_state = loaded; 545 } 546 547 void InstanceKlass::link_class(TRAPS) { 548 assert(is_loaded(), "must be loaded"); 549 if (!is_linked()) { 550 HandleMark hm(THREAD); 551 instanceKlassHandle this_k(THREAD, this); 552 link_class_impl(this_k, true, CHECK); 553 } 554 } 555 556 // Called to verify that a class can link during initialization, without 557 // throwing a VerifyError. 558 bool InstanceKlass::link_class_or_fail(TRAPS) { 559 assert(is_loaded(), "must be loaded"); 560 if (!is_linked()) { 561 HandleMark hm(THREAD); 562 instanceKlassHandle this_k(THREAD, this); 563 link_class_impl(this_k, false, CHECK_false); 564 } 565 return is_linked(); 566 } 567 568 bool InstanceKlass::link_class_impl( 569 instanceKlassHandle this_k, bool throw_verifyerror, TRAPS) { 570 // check for error state 571 if (this_k->is_in_error_state()) { 572 ResourceMark rm(THREAD); 573 THROW_MSG_(vmSymbols::java_lang_NoClassDefFoundError(), 574 this_k->external_name(), false); 575 } 576 // return if already verified 577 if (this_k->is_linked()) { 578 return true; 579 } 580 581 // Timing 582 // timer handles recursion 583 assert(THREAD->is_Java_thread(), "non-JavaThread in link_class_impl"); 584 JavaThread* jt = (JavaThread*)THREAD; 585 586 // link super class before linking this class 587 instanceKlassHandle super(THREAD, this_k->super()); 588 if (super.not_null()) { 589 if (super->is_interface()) { // check if super class is an interface 590 ResourceMark rm(THREAD); 591 Exceptions::fthrow( 592 THREAD_AND_LOCATION, 593 vmSymbols::java_lang_IncompatibleClassChangeError(), 594 "class %s has interface %s as super class", 595 this_k->external_name(), 596 super->external_name() 597 ); 598 return false; 599 } 600 601 link_class_impl(super, throw_verifyerror, CHECK_false); 602 } 603 604 // link all interfaces implemented by this class before linking this class 605 Array<Klass*>* interfaces = this_k->local_interfaces(); 606 int num_interfaces = interfaces->length(); 607 for (int index = 0; index < num_interfaces; index++) { 608 HandleMark hm(THREAD); 609 instanceKlassHandle ih(THREAD, interfaces->at(index)); 610 link_class_impl(ih, throw_verifyerror, CHECK_false); 611 } 612 613 // in case the class is linked in the process of linking its superclasses 614 if (this_k->is_linked()) { 615 return true; 616 } 617 618 // trace only the link time for this klass that includes 619 // the verification time 620 PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(), 621 ClassLoader::perf_class_link_selftime(), 622 ClassLoader::perf_classes_linked(), 623 jt->get_thread_stat()->perf_recursion_counts_addr(), 624 jt->get_thread_stat()->perf_timers_addr(), 625 PerfClassTraceTime::CLASS_LINK); 626 627 // verification & rewriting 628 { 629 oop init_lock = this_k->init_lock(); 630 ObjectLocker ol(init_lock, THREAD, init_lock != NULL); 631 // rewritten will have been set if loader constraint error found 632 // on an earlier link attempt 633 // don't verify or rewrite if already rewritten 634 635 if (!this_k->is_linked()) { 636 if (!this_k->is_rewritten()) { 637 { 638 // Timer includes any side effects of class verification (resolution, 639 // etc), but not recursive entry into verify_code(). 640 PerfClassTraceTime timer(ClassLoader::perf_class_verify_time(), 641 ClassLoader::perf_class_verify_selftime(), 642 ClassLoader::perf_classes_verified(), 643 jt->get_thread_stat()->perf_recursion_counts_addr(), 644 jt->get_thread_stat()->perf_timers_addr(), 645 PerfClassTraceTime::CLASS_VERIFY); 646 bool verify_ok = verify_code(this_k, throw_verifyerror, THREAD); 647 if (!verify_ok) { 648 return false; 649 } 650 } 651 652 // Just in case a side-effect of verify linked this class already 653 // (which can sometimes happen since the verifier loads classes 654 // using custom class loaders, which are free to initialize things) 655 if (this_k->is_linked()) { 656 return true; 657 } 658 659 // also sets rewritten 660 this_k->rewrite_class(CHECK_false); 661 } 662 663 // relocate jsrs and link methods after they are all rewritten 664 this_k->link_methods(CHECK_false); 665 666 // Initialize the vtable and interface table after 667 // methods have been rewritten since rewrite may 668 // fabricate new Method*s. 669 // also does loader constraint checking 670 if (!this_k()->is_shared()) { 671 ResourceMark rm(THREAD); 672 this_k->vtable()->initialize_vtable(true, CHECK_false); 673 this_k->itable()->initialize_itable(true, CHECK_false); 674 } 675 #ifdef ASSERT 676 else { 677 ResourceMark rm(THREAD); 678 this_k->vtable()->verify(tty, true); 679 // In case itable verification is ever added. 680 // this_k->itable()->verify(tty, true); 681 } 682 #endif 683 this_k->set_init_state(linked); 684 if (JvmtiExport::should_post_class_prepare()) { 685 Thread *thread = THREAD; 686 assert(thread->is_Java_thread(), "thread->is_Java_thread()"); 687 JvmtiExport::post_class_prepare((JavaThread *) thread, this_k()); 688 } 689 } 690 } 691 return true; 692 } 693 694 695 // Rewrite the byte codes of all of the methods of a class. 696 // The rewriter must be called exactly once. Rewriting must happen after 697 // verification but before the first method of the class is executed. 698 void InstanceKlass::rewrite_class(TRAPS) { 699 assert(is_loaded(), "must be loaded"); 700 instanceKlassHandle this_k(THREAD, this); 701 if (this_k->is_rewritten()) { 702 assert(this_k()->is_shared(), "rewriting an unshared class?"); 703 return; 704 } 705 Rewriter::rewrite(this_k, CHECK); 706 this_k->set_rewritten(); 707 } 708 709 // Now relocate and link method entry points after class is rewritten. 710 // This is outside is_rewritten flag. In case of an exception, it can be 711 // executed more than once. 712 void InstanceKlass::link_methods(TRAPS) { 713 int len = methods()->length(); 714 for (int i = len-1; i >= 0; i--) { 715 methodHandle m(THREAD, methods()->at(i)); 716 717 // Set up method entry points for compiler and interpreter . 718 m->link_method(m, CHECK); 719 720 // This is for JVMTI and unrelated to relocator but the last thing we do 721 #ifdef ASSERT 722 if (StressMethodComparator) { 723 ResourceMark rm(THREAD); 724 static int nmc = 0; 725 for (int j = i; j >= 0 && j >= i-4; j--) { 726 if ((++nmc % 1000) == 0) tty->print_cr("Have run MethodComparator %d times...", nmc); 727 bool z = MethodComparator::methods_EMCP(m(), 728 methods()->at(j)); 729 if (j == i && !z) { 730 tty->print("MethodComparator FAIL: "); m->print(); m->print_codes(); 731 assert(z, "method must compare equal to itself"); 732 } 733 } 734 } 735 #endif //ASSERT 736 } 737 } 738 739 // Eagerly initialize superinterfaces that declare default methods (concrete instance: any access) 740 void InstanceKlass::initialize_super_interfaces(instanceKlassHandle this_k, TRAPS) { 741 if (this_k->has_default_methods()) { 742 for (int i = 0; i < this_k->local_interfaces()->length(); ++i) { 743 Klass* iface = this_k->local_interfaces()->at(i); 744 InstanceKlass* ik = InstanceKlass::cast(iface); 745 if (ik->should_be_initialized()) { 746 if (ik->has_default_methods()) { 747 ik->initialize_super_interfaces(ik, THREAD); 748 } 749 // Only initialize() interfaces that "declare" concrete methods. 750 // has_default_methods drives searching superinterfaces since it 751 // means has_default_methods in its superinterface hierarchy 752 if (!HAS_PENDING_EXCEPTION && ik->declares_default_methods()) { 753 ik->initialize(THREAD); 754 } 755 if (HAS_PENDING_EXCEPTION) { 756 Handle e(THREAD, PENDING_EXCEPTION); 757 CLEAR_PENDING_EXCEPTION; 758 { 759 EXCEPTION_MARK; 760 // Locks object, set state, and notify all waiting threads 761 this_k->set_initialization_state_and_notify( 762 initialization_error, THREAD); 763 764 // ignore any exception thrown, superclass initialization error is 765 // thrown below 766 CLEAR_PENDING_EXCEPTION; 767 } 768 THROW_OOP(e()); 769 } 770 } 771 } 772 } 773 } 774 775 void InstanceKlass::initialize_impl(instanceKlassHandle this_k, TRAPS) { 776 // Make sure klass is linked (verified) before initialization 777 // A class could already be verified, since it has been reflected upon. 778 this_k->link_class(CHECK); 779 780 DTRACE_CLASSINIT_PROBE(required, InstanceKlass::cast(this_k()), -1); 781 782 bool wait = false; 783 784 // refer to the JVM book page 47 for description of steps 785 // Step 1 786 { 787 oop init_lock = this_k->init_lock(); 788 ObjectLocker ol(init_lock, THREAD, init_lock != NULL); 789 790 Thread *self = THREAD; // it's passed the current thread 791 792 // Step 2 793 // If we were to use wait() instead of waitInterruptibly() then 794 // we might end up throwing IE from link/symbol resolution sites 795 // that aren't expected to throw. This would wreak havoc. See 6320309. 796 while(this_k->is_being_initialized() && !this_k->is_reentrant_initialization(self)) { 797 wait = true; 798 ol.waitUninterruptibly(CHECK); 799 } 800 801 // Step 3 802 if (this_k->is_being_initialized() && this_k->is_reentrant_initialization(self)) { 803 DTRACE_CLASSINIT_PROBE_WAIT(recursive, InstanceKlass::cast(this_k()), -1,wait); 804 return; 805 } 806 807 // Step 4 808 if (this_k->is_initialized()) { 809 DTRACE_CLASSINIT_PROBE_WAIT(concurrent, InstanceKlass::cast(this_k()), -1,wait); 810 return; 811 } 812 813 // Step 5 814 if (this_k->is_in_error_state()) { 815 DTRACE_CLASSINIT_PROBE_WAIT(erroneous, InstanceKlass::cast(this_k()), -1,wait); 816 ResourceMark rm(THREAD); 817 const char* desc = "Could not initialize class "; 818 const char* className = this_k->external_name(); 819 size_t msglen = strlen(desc) + strlen(className) + 1; 820 char* message = NEW_RESOURCE_ARRAY(char, msglen); 821 if (NULL == message) { 822 // Out of memory: can't create detailed error message 823 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), className); 824 } else { 825 jio_snprintf(message, msglen, "%s%s", desc, className); 826 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), message); 827 } 828 } 829 830 // Step 6 831 this_k->set_init_state(being_initialized); 832 this_k->set_init_thread(self); 833 } 834 835 // Step 7 836 Klass* super_klass = this_k->super(); 837 if (super_klass != NULL && !this_k->is_interface() && super_klass->should_be_initialized()) { 838 super_klass->initialize(THREAD); 839 840 if (HAS_PENDING_EXCEPTION) { 841 Handle e(THREAD, PENDING_EXCEPTION); 842 CLEAR_PENDING_EXCEPTION; 843 { 844 EXCEPTION_MARK; 845 this_k->set_initialization_state_and_notify(initialization_error, THREAD); // Locks object, set state, and notify all waiting threads 846 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, superclass initialization error is thrown below 847 } 848 DTRACE_CLASSINIT_PROBE_WAIT(super__failed, InstanceKlass::cast(this_k()), -1,wait); 849 THROW_OOP(e()); 850 } 851 } 852 853 // Recursively initialize any superinterfaces that declare default methods 854 // Only need to recurse if has_default_methods which includes declaring and 855 // inheriting default methods 856 if (this_k->has_default_methods()) { 857 this_k->initialize_super_interfaces(this_k, CHECK); 858 } 859 860 // Step 8 861 { 862 assert(THREAD->is_Java_thread(), "non-JavaThread in initialize_impl"); 863 JavaThread* jt = (JavaThread*)THREAD; 864 DTRACE_CLASSINIT_PROBE_WAIT(clinit, InstanceKlass::cast(this_k()), -1,wait); 865 // Timer includes any side effects of class initialization (resolution, 866 // etc), but not recursive entry into call_class_initializer(). 867 PerfClassTraceTime timer(ClassLoader::perf_class_init_time(), 868 ClassLoader::perf_class_init_selftime(), 869 ClassLoader::perf_classes_inited(), 870 jt->get_thread_stat()->perf_recursion_counts_addr(), 871 jt->get_thread_stat()->perf_timers_addr(), 872 PerfClassTraceTime::CLASS_CLINIT); 873 this_k->call_class_initializer(THREAD); 874 } 875 876 // Step 9 877 if (!HAS_PENDING_EXCEPTION) { 878 this_k->set_initialization_state_and_notify(fully_initialized, CHECK); 879 { ResourceMark rm(THREAD); 880 debug_only(this_k->vtable()->verify(tty, true);) 881 } 882 } 883 else { 884 // Step 10 and 11 885 Handle e(THREAD, PENDING_EXCEPTION); 886 CLEAR_PENDING_EXCEPTION; 887 // JVMTI has already reported the pending exception 888 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError 889 JvmtiExport::clear_detected_exception((JavaThread*)THREAD); 890 { 891 EXCEPTION_MARK; 892 this_k->set_initialization_state_and_notify(initialization_error, THREAD); 893 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, class initialization error is thrown below 894 // JVMTI has already reported the pending exception 895 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError 896 JvmtiExport::clear_detected_exception((JavaThread*)THREAD); 897 } 898 DTRACE_CLASSINIT_PROBE_WAIT(error, InstanceKlass::cast(this_k()), -1,wait); 899 if (e->is_a(SystemDictionary::Error_klass())) { 900 THROW_OOP(e()); 901 } else { 902 JavaCallArguments args(e); 903 THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(), 904 vmSymbols::throwable_void_signature(), 905 &args); 906 } 907 } 908 DTRACE_CLASSINIT_PROBE_WAIT(end, InstanceKlass::cast(this_k()), -1,wait); 909 } 910 911 912 // Note: implementation moved to static method to expose the this pointer. 913 void InstanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) { 914 instanceKlassHandle kh(THREAD, this); 915 set_initialization_state_and_notify_impl(kh, state, CHECK); 916 } 917 918 void InstanceKlass::set_initialization_state_and_notify_impl(instanceKlassHandle this_k, ClassState state, TRAPS) { 919 oop init_lock = this_k->init_lock(); 920 ObjectLocker ol(init_lock, THREAD, init_lock != NULL); 921 this_k->set_init_state(state); 922 this_k->fence_and_clear_init_lock(); 923 ol.notify_all(CHECK); 924 } 925 926 // The embedded _implementor field can only record one implementor. 927 // When there are more than one implementors, the _implementor field 928 // is set to the interface Klass* itself. Following are the possible 929 // values for the _implementor field: 930 // NULL - no implementor 931 // implementor Klass* - one implementor 932 // self - more than one implementor 933 // 934 // The _implementor field only exists for interfaces. 935 void InstanceKlass::add_implementor(Klass* k) { 936 assert(Compile_lock->owned_by_self(), ""); 937 assert(is_interface(), "not interface"); 938 // Filter out my subinterfaces. 939 // (Note: Interfaces are never on the subklass list.) 940 if (InstanceKlass::cast(k)->is_interface()) return; 941 942 // Filter out subclasses whose supers already implement me. 943 // (Note: CHA must walk subclasses of direct implementors 944 // in order to locate indirect implementors.) 945 Klass* sk = InstanceKlass::cast(k)->super(); 946 if (sk != NULL && InstanceKlass::cast(sk)->implements_interface(this)) 947 // We only need to check one immediate superclass, since the 948 // implements_interface query looks at transitive_interfaces. 949 // Any supers of the super have the same (or fewer) transitive_interfaces. 950 return; 951 952 Klass* ik = implementor(); 953 if (ik == NULL) { 954 set_implementor(k); 955 } else if (ik != this) { 956 // There is already an implementor. Use itself as an indicator of 957 // more than one implementors. 958 set_implementor(this); 959 } 960 961 // The implementor also implements the transitive_interfaces 962 for (int index = 0; index < local_interfaces()->length(); index++) { 963 InstanceKlass::cast(local_interfaces()->at(index))->add_implementor(k); 964 } 965 } 966 967 void InstanceKlass::init_implementor() { 968 if (is_interface()) { 969 set_implementor(NULL); 970 } 971 } 972 973 974 void InstanceKlass::process_interfaces(Thread *thread) { 975 // link this class into the implementors list of every interface it implements 976 for (int i = local_interfaces()->length() - 1; i >= 0; i--) { 977 assert(local_interfaces()->at(i)->is_klass(), "must be a klass"); 978 InstanceKlass* interf = InstanceKlass::cast(local_interfaces()->at(i)); 979 assert(interf->is_interface(), "expected interface"); 980 interf->add_implementor(this); 981 } 982 } 983 984 bool InstanceKlass::can_be_primary_super_slow() const { 985 if (is_interface()) 986 return false; 987 else 988 return Klass::can_be_primary_super_slow(); 989 } 990 991 GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots) { 992 // The secondaries are the implemented interfaces. 993 InstanceKlass* ik = InstanceKlass::cast(this); 994 Array<Klass*>* interfaces = ik->transitive_interfaces(); 995 int num_secondaries = num_extra_slots + interfaces->length(); 996 if (num_secondaries == 0) { 997 // Must share this for correct bootstrapping! 998 set_secondary_supers(Universe::the_empty_klass_array()); 999 return NULL; 1000 } else if (num_extra_slots == 0) { 1001 // The secondary super list is exactly the same as the transitive interfaces. 1002 // Redefine classes has to be careful not to delete this! 1003 set_secondary_supers(interfaces); 1004 return NULL; 1005 } else { 1006 // Copy transitive interfaces to a temporary growable array to be constructed 1007 // into the secondary super list with extra slots. 1008 GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length()); 1009 for (int i = 0; i < interfaces->length(); i++) { 1010 secondaries->push(interfaces->at(i)); 1011 } 1012 return secondaries; 1013 } 1014 } 1015 1016 bool InstanceKlass::compute_is_subtype_of(Klass* k) { 1017 if (k->is_interface()) { 1018 return implements_interface(k); 1019 } else { 1020 return Klass::compute_is_subtype_of(k); 1021 } 1022 } 1023 1024 bool InstanceKlass::implements_interface(Klass* k) const { 1025 if (this == k) return true; 1026 assert(k->is_interface(), "should be an interface class"); 1027 for (int i = 0; i < transitive_interfaces()->length(); i++) { 1028 if (transitive_interfaces()->at(i) == k) { 1029 return true; 1030 } 1031 } 1032 return false; 1033 } 1034 1035 bool InstanceKlass::is_same_or_direct_interface(Klass *k) const { 1036 // Verify direct super interface 1037 if (this == k) return true; 1038 assert(k->is_interface(), "should be an interface class"); 1039 for (int i = 0; i < local_interfaces()->length(); i++) { 1040 if (local_interfaces()->at(i) == k) { 1041 return true; 1042 } 1043 } 1044 return false; 1045 } 1046 1047 objArrayOop InstanceKlass::allocate_objArray(int n, int length, TRAPS) { 1048 if (length < 0) THROW_0(vmSymbols::java_lang_NegativeArraySizeException()); 1049 if (length > arrayOopDesc::max_array_length(T_OBJECT)) { 1050 report_java_out_of_memory("Requested array size exceeds VM limit"); 1051 JvmtiExport::post_array_size_exhausted(); 1052 THROW_OOP_0(Universe::out_of_memory_error_array_size()); 1053 } 1054 int size = objArrayOopDesc::object_size(length); 1055 Klass* ak = array_klass(n, CHECK_NULL); 1056 KlassHandle h_ak (THREAD, ak); 1057 objArrayOop o = 1058 (objArrayOop)CollectedHeap::array_allocate(h_ak, size, length, CHECK_NULL); 1059 return o; 1060 } 1061 1062 instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) { 1063 if (TraceFinalizerRegistration) { 1064 tty->print("Registered "); 1065 i->print_value_on(tty); 1066 tty->print_cr(" (" INTPTR_FORMAT ") as finalizable", (address)i); 1067 } 1068 instanceHandle h_i(THREAD, i); 1069 // Pass the handle as argument, JavaCalls::call expects oop as jobjects 1070 JavaValue result(T_VOID); 1071 JavaCallArguments args(h_i); 1072 methodHandle mh (THREAD, Universe::finalizer_register_method()); 1073 JavaCalls::call(&result, mh, &args, CHECK_NULL); 1074 return h_i(); 1075 } 1076 1077 instanceOop InstanceKlass::allocate_instance(TRAPS) { 1078 bool has_finalizer_flag = has_finalizer(); // Query before possible GC 1079 int size = size_helper(); // Query before forming handle. 1080 1081 KlassHandle h_k(THREAD, this); 1082 1083 instanceOop i; 1084 1085 i = (instanceOop)CollectedHeap::obj_allocate(h_k, size, CHECK_NULL); 1086 if (has_finalizer_flag && !RegisterFinalizersAtInit) { 1087 i = register_finalizer(i, CHECK_NULL); 1088 } 1089 return i; 1090 } 1091 1092 void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) { 1093 if (is_interface() || is_abstract()) { 1094 ResourceMark rm(THREAD); 1095 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError() 1096 : vmSymbols::java_lang_InstantiationException(), external_name()); 1097 } 1098 if (this == SystemDictionary::Class_klass()) { 1099 ResourceMark rm(THREAD); 1100 THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError() 1101 : vmSymbols::java_lang_IllegalAccessException(), external_name()); 1102 } 1103 } 1104 1105 Klass* InstanceKlass::array_klass_impl(bool or_null, int n, TRAPS) { 1106 instanceKlassHandle this_k(THREAD, this); 1107 return array_klass_impl(this_k, or_null, n, THREAD); 1108 } 1109 1110 Klass* InstanceKlass::array_klass_impl(instanceKlassHandle this_k, bool or_null, int n, TRAPS) { 1111 if (this_k->array_klasses() == NULL) { 1112 if (or_null) return NULL; 1113 1114 ResourceMark rm; 1115 JavaThread *jt = (JavaThread *)THREAD; 1116 { 1117 // Atomic creation of array_klasses 1118 MutexLocker mc(Compile_lock, THREAD); // for vtables 1119 MutexLocker ma(MultiArray_lock, THREAD); 1120 1121 // Check if update has already taken place 1122 if (this_k->array_klasses() == NULL) { 1123 Klass* k = ObjArrayKlass::allocate_objArray_klass(this_k->class_loader_data(), 1, this_k, CHECK_NULL); 1124 this_k->set_array_klasses(k); 1125 } 1126 } 1127 } 1128 // _this will always be set at this point 1129 ObjArrayKlass* oak = (ObjArrayKlass*)this_k->array_klasses(); 1130 if (or_null) { 1131 return oak->array_klass_or_null(n); 1132 } 1133 return oak->array_klass(n, THREAD); 1134 } 1135 1136 Klass* InstanceKlass::array_klass_impl(bool or_null, TRAPS) { 1137 return array_klass_impl(or_null, 1, THREAD); 1138 } 1139 1140 void InstanceKlass::call_class_initializer(TRAPS) { 1141 instanceKlassHandle ik (THREAD, this); 1142 call_class_initializer_impl(ik, THREAD); 1143 } 1144 1145 static int call_class_initializer_impl_counter = 0; // for debugging 1146 1147 Method* InstanceKlass::class_initializer() { 1148 Method* clinit = find_method( 1149 vmSymbols::class_initializer_name(), vmSymbols::void_method_signature()); 1150 if (clinit != NULL && clinit->has_valid_initializer_flags()) { 1151 return clinit; 1152 } 1153 return NULL; 1154 } 1155 1156 void InstanceKlass::call_class_initializer_impl(instanceKlassHandle this_k, TRAPS) { 1157 if (ReplayCompiles && 1158 (ReplaySuppressInitializers == 1 || 1159 ReplaySuppressInitializers >= 2 && this_k->class_loader() != NULL)) { 1160 // Hide the existence of the initializer for the purpose of replaying the compile 1161 return; 1162 } 1163 1164 methodHandle h_method(THREAD, this_k->class_initializer()); 1165 assert(!this_k->is_initialized(), "we cannot initialize twice"); 1166 if (TraceClassInitialization) { 1167 tty->print("%d Initializing ", call_class_initializer_impl_counter++); 1168 this_k->name()->print_value(); 1169 tty->print_cr("%s (" INTPTR_FORMAT ")", h_method() == NULL ? "(no method)" : "", (address)this_k()); 1170 } 1171 if (h_method() != NULL) { 1172 JavaCallArguments args; // No arguments 1173 JavaValue result(T_VOID); 1174 JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args) 1175 } 1176 } 1177 1178 1179 void InstanceKlass::mask_for(methodHandle method, int bci, 1180 InterpreterOopMap* entry_for) { 1181 // Dirty read, then double-check under a lock. 1182 if (_oop_map_cache == NULL) { 1183 // Otherwise, allocate a new one. 1184 MutexLocker x(OopMapCacheAlloc_lock); 1185 // First time use. Allocate a cache in C heap 1186 if (_oop_map_cache == NULL) { 1187 // Release stores from OopMapCache constructor before assignment 1188 // to _oop_map_cache. C++ compilers on ppc do not emit the 1189 // required memory barrier only because of the volatile 1190 // qualifier of _oop_map_cache. 1191 OrderAccess::release_store_ptr(&_oop_map_cache, new OopMapCache()); 1192 } 1193 } 1194 // _oop_map_cache is constant after init; lookup below does is own locking. 1195 _oop_map_cache->lookup(method, bci, entry_for); 1196 } 1197 1198 1199 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const { 1200 for (JavaFieldStream fs(this); !fs.done(); fs.next()) { 1201 Symbol* f_name = fs.name(); 1202 Symbol* f_sig = fs.signature(); 1203 if (f_name == name && f_sig == sig) { 1204 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index()); 1205 return true; 1206 } 1207 } 1208 return false; 1209 } 1210 1211 1212 Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const { 1213 const int n = local_interfaces()->length(); 1214 for (int i = 0; i < n; i++) { 1215 Klass* intf1 = local_interfaces()->at(i); 1216 assert(intf1->is_interface(), "just checking type"); 1217 // search for field in current interface 1218 if (InstanceKlass::cast(intf1)->find_local_field(name, sig, fd)) { 1219 assert(fd->is_static(), "interface field must be static"); 1220 return intf1; 1221 } 1222 // search for field in direct superinterfaces 1223 Klass* intf2 = InstanceKlass::cast(intf1)->find_interface_field(name, sig, fd); 1224 if (intf2 != NULL) return intf2; 1225 } 1226 // otherwise field lookup fails 1227 return NULL; 1228 } 1229 1230 1231 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const { 1232 // search order according to newest JVM spec (5.4.3.2, p.167). 1233 // 1) search for field in current klass 1234 if (find_local_field(name, sig, fd)) { 1235 return const_cast<InstanceKlass*>(this); 1236 } 1237 // 2) search for field recursively in direct superinterfaces 1238 { Klass* intf = find_interface_field(name, sig, fd); 1239 if (intf != NULL) return intf; 1240 } 1241 // 3) apply field lookup recursively if superclass exists 1242 { Klass* supr = super(); 1243 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, fd); 1244 } 1245 // 4) otherwise field lookup fails 1246 return NULL; 1247 } 1248 1249 1250 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const { 1251 // search order according to newest JVM spec (5.4.3.2, p.167). 1252 // 1) search for field in current klass 1253 if (find_local_field(name, sig, fd)) { 1254 if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this); 1255 } 1256 // 2) search for field recursively in direct superinterfaces 1257 if (is_static) { 1258 Klass* intf = find_interface_field(name, sig, fd); 1259 if (intf != NULL) return intf; 1260 } 1261 // 3) apply field lookup recursively if superclass exists 1262 { Klass* supr = super(); 1263 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, is_static, fd); 1264 } 1265 // 4) otherwise field lookup fails 1266 return NULL; 1267 } 1268 1269 1270 bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const { 1271 for (JavaFieldStream fs(this); !fs.done(); fs.next()) { 1272 if (fs.offset() == offset) { 1273 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index()); 1274 if (fd->is_static() == is_static) return true; 1275 } 1276 } 1277 return false; 1278 } 1279 1280 1281 bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const { 1282 Klass* klass = const_cast<InstanceKlass*>(this); 1283 while (klass != NULL) { 1284 if (InstanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) { 1285 return true; 1286 } 1287 klass = klass->super(); 1288 } 1289 return false; 1290 } 1291 1292 1293 void InstanceKlass::methods_do(void f(Method* method)) { 1294 // Methods aren't stable until they are loaded. This can be read outside 1295 // a lock through the ClassLoaderData for profiling 1296 if (!is_loaded()) { 1297 return; 1298 } 1299 1300 int len = methods()->length(); 1301 for (int index = 0; index < len; index++) { 1302 Method* m = methods()->at(index); 1303 assert(m->is_method(), "must be method"); 1304 f(m); 1305 } 1306 } 1307 1308 1309 void InstanceKlass::do_local_static_fields(FieldClosure* cl) { 1310 for (JavaFieldStream fs(this); !fs.done(); fs.next()) { 1311 if (fs.access_flags().is_static()) { 1312 fieldDescriptor& fd = fs.field_descriptor(); 1313 cl->do_field(&fd); 1314 } 1315 } 1316 } 1317 1318 1319 void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle mirror, TRAPS) { 1320 instanceKlassHandle h_this(THREAD, this); 1321 do_local_static_fields_impl(h_this, f, mirror, CHECK); 1322 } 1323 1324 1325 void InstanceKlass::do_local_static_fields_impl(instanceKlassHandle this_k, 1326 void f(fieldDescriptor* fd, Handle, TRAPS), Handle mirror, TRAPS) { 1327 for (JavaFieldStream fs(this_k()); !fs.done(); fs.next()) { 1328 if (fs.access_flags().is_static()) { 1329 fieldDescriptor& fd = fs.field_descriptor(); 1330 f(&fd, mirror, CHECK); 1331 } 1332 } 1333 } 1334 1335 1336 static int compare_fields_by_offset(int* a, int* b) { 1337 return a[0] - b[0]; 1338 } 1339 1340 void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) { 1341 InstanceKlass* super = superklass(); 1342 if (super != NULL) { 1343 super->do_nonstatic_fields(cl); 1344 } 1345 fieldDescriptor fd; 1346 int length = java_fields_count(); 1347 // In DebugInfo nonstatic fields are sorted by offset. 1348 int* fields_sorted = NEW_C_HEAP_ARRAY(int, 2*(length+1), mtClass); 1349 int j = 0; 1350 for (int i = 0; i < length; i += 1) { 1351 fd.reinitialize(this, i); 1352 if (!fd.is_static()) { 1353 fields_sorted[j + 0] = fd.offset(); 1354 fields_sorted[j + 1] = i; 1355 j += 2; 1356 } 1357 } 1358 if (j > 0) { 1359 length = j; 1360 // _sort_Fn is defined in growableArray.hpp. 1361 qsort(fields_sorted, length/2, 2*sizeof(int), (_sort_Fn)compare_fields_by_offset); 1362 for (int i = 0; i < length; i += 2) { 1363 fd.reinitialize(this, fields_sorted[i + 1]); 1364 assert(!fd.is_static() && fd.offset() == fields_sorted[i], "only nonstatic fields"); 1365 cl->do_field(&fd); 1366 } 1367 } 1368 FREE_C_HEAP_ARRAY(int, fields_sorted); 1369 } 1370 1371 1372 void InstanceKlass::array_klasses_do(void f(Klass* k, TRAPS), TRAPS) { 1373 if (array_klasses() != NULL) 1374 ArrayKlass::cast(array_klasses())->array_klasses_do(f, THREAD); 1375 } 1376 1377 void InstanceKlass::array_klasses_do(void f(Klass* k)) { 1378 if (array_klasses() != NULL) 1379 ArrayKlass::cast(array_klasses())->array_klasses_do(f); 1380 } 1381 1382 #ifdef ASSERT 1383 static int linear_search(Array<Method*>* methods, Symbol* name, Symbol* signature) { 1384 int len = methods->length(); 1385 for (int index = 0; index < len; index++) { 1386 Method* m = methods->at(index); 1387 assert(m->is_method(), "must be method"); 1388 if (m->signature() == signature && m->name() == name) { 1389 return index; 1390 } 1391 } 1392 return -1; 1393 } 1394 #endif 1395 1396 static int binary_search(Array<Method*>* methods, Symbol* name) { 1397 int len = methods->length(); 1398 // methods are sorted, so do binary search 1399 int l = 0; 1400 int h = len - 1; 1401 while (l <= h) { 1402 int mid = (l + h) >> 1; 1403 Method* m = methods->at(mid); 1404 assert(m->is_method(), "must be method"); 1405 int res = m->name()->fast_compare(name); 1406 if (res == 0) { 1407 return mid; 1408 } else if (res < 0) { 1409 l = mid + 1; 1410 } else { 1411 h = mid - 1; 1412 } 1413 } 1414 return -1; 1415 } 1416 1417 // find_method looks up the name/signature in the local methods array 1418 Method* InstanceKlass::find_method(Symbol* name, Symbol* signature) const { 1419 return find_method_impl(name, signature, find_overpass, find_static); 1420 } 1421 1422 Method* InstanceKlass::find_method_impl(Symbol* name, Symbol* signature, 1423 OverpassLookupMode overpass_mode, StaticLookupMode static_mode) const { 1424 return InstanceKlass::find_method_impl(methods(), name, signature, overpass_mode, static_mode); 1425 } 1426 1427 // find_instance_method looks up the name/signature in the local methods array 1428 // and skips over static methods 1429 Method* InstanceKlass::find_instance_method( 1430 Array<Method*>* methods, Symbol* name, Symbol* signature) { 1431 Method* meth = InstanceKlass::find_method_impl(methods, name, signature, 1432 find_overpass, skip_static); 1433 assert(((meth == NULL) || !meth->is_static()), "find_instance_method should have skipped statics"); 1434 return meth; 1435 } 1436 1437 // find_instance_method looks up the name/signature in the local methods array 1438 // and skips over static methods 1439 Method* InstanceKlass::find_instance_method(Symbol* name, Symbol* signature) { 1440 return InstanceKlass::find_instance_method(methods(), name, signature); 1441 } 1442 1443 // find_method looks up the name/signature in the local methods array 1444 Method* InstanceKlass::find_method( 1445 Array<Method*>* methods, Symbol* name, Symbol* signature) { 1446 return InstanceKlass::find_method_impl(methods, name, signature, find_overpass, find_static); 1447 } 1448 1449 Method* InstanceKlass::find_method_impl( 1450 Array<Method*>* methods, Symbol* name, Symbol* signature, OverpassLookupMode overpass_mode, StaticLookupMode static_mode) { 1451 int hit = find_method_index(methods, name, signature, overpass_mode, static_mode); 1452 return hit >= 0 ? methods->at(hit): NULL; 1453 } 1454 1455 bool InstanceKlass::method_matches(Method* m, Symbol* signature, bool skipping_overpass, bool skipping_static) { 1456 return (m->signature() == signature) && 1457 (!skipping_overpass || !m->is_overpass()) && 1458 (!skipping_static || !m->is_static()); 1459 } 1460 1461 // Used directly for default_methods to find the index into the 1462 // default_vtable_indices, and indirectly by find_method 1463 // find_method_index looks in the local methods array to return the index 1464 // of the matching name/signature. If, overpass methods are being ignored, 1465 // the search continues to find a potential non-overpass match. This capability 1466 // is important during method resolution to prefer a static method, for example, 1467 // over an overpass method. 1468 int InstanceKlass::find_method_index( 1469 Array<Method*>* methods, Symbol* name, Symbol* signature, OverpassLookupMode overpass_mode, StaticLookupMode static_mode) { 1470 bool skipping_overpass = (overpass_mode == skip_overpass); 1471 bool skipping_static = (static_mode == skip_static); 1472 int hit = binary_search(methods, name); 1473 if (hit != -1) { 1474 Method* m = methods->at(hit); 1475 1476 // Do linear search to find matching signature. First, quick check 1477 // for common case, ignoring overpasses if requested. 1478 if (method_matches(m, signature, skipping_overpass, skipping_static)) return hit; 1479 1480 // search downwards through overloaded methods 1481 int i; 1482 for (i = hit - 1; i >= 0; --i) { 1483 Method* m = methods->at(i); 1484 assert(m->is_method(), "must be method"); 1485 if (m->name() != name) break; 1486 if (method_matches(m, signature, skipping_overpass, skipping_static)) return i; 1487 } 1488 // search upwards 1489 for (i = hit + 1; i < methods->length(); ++i) { 1490 Method* m = methods->at(i); 1491 assert(m->is_method(), "must be method"); 1492 if (m->name() != name) break; 1493 if (method_matches(m, signature, skipping_overpass, skipping_static)) return i; 1494 } 1495 // not found 1496 #ifdef ASSERT 1497 int index = (skipping_overpass || skipping_static) ? -1 : linear_search(methods, name, signature); 1498 assert(index == -1, err_msg("binary search should have found entry %d", index)); 1499 #endif 1500 } 1501 return -1; 1502 } 1503 int InstanceKlass::find_method_by_name(Symbol* name, int* end) { 1504 return find_method_by_name(methods(), name, end); 1505 } 1506 1507 int InstanceKlass::find_method_by_name( 1508 Array<Method*>* methods, Symbol* name, int* end_ptr) { 1509 assert(end_ptr != NULL, "just checking"); 1510 int start = binary_search(methods, name); 1511 int end = start + 1; 1512 if (start != -1) { 1513 while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start; 1514 while (end < methods->length() && (methods->at(end))->name() == name) ++end; 1515 *end_ptr = end; 1516 return start; 1517 } 1518 return -1; 1519 } 1520 1521 // uncached_lookup_method searches both the local class methods array and all 1522 // superclasses methods arrays, skipping any overpass methods in superclasses. 1523 Method* InstanceKlass::uncached_lookup_method(Symbol* name, Symbol* signature, OverpassLookupMode overpass_mode) const { 1524 OverpassLookupMode overpass_local_mode = overpass_mode; 1525 Klass* klass = const_cast<InstanceKlass*>(this); 1526 while (klass != NULL) { 1527 Method* method = InstanceKlass::cast(klass)->find_method_impl(name, signature, overpass_local_mode, find_static); 1528 if (method != NULL) { 1529 return method; 1530 } 1531 klass = InstanceKlass::cast(klass)->super(); 1532 overpass_local_mode = skip_overpass; // Always ignore overpass methods in superclasses 1533 } 1534 return NULL; 1535 } 1536 1537 #ifdef ASSERT 1538 // search through class hierarchy and return true if this class or 1539 // one of the superclasses was redefined 1540 bool InstanceKlass::has_redefined_this_or_super() const { 1541 const InstanceKlass* klass = this; 1542 while (klass != NULL) { 1543 if (klass->has_been_redefined()) { 1544 return true; 1545 } 1546 klass = InstanceKlass::cast(klass->super()); 1547 } 1548 return false; 1549 } 1550 #endif 1551 1552 // lookup a method in the default methods list then in all transitive interfaces 1553 // Do NOT return private or static methods 1554 Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name, 1555 Symbol* signature) const { 1556 Method* m = NULL; 1557 if (default_methods() != NULL) { 1558 m = find_method(default_methods(), name, signature); 1559 } 1560 // Look up interfaces 1561 if (m == NULL) { 1562 m = lookup_method_in_all_interfaces(name, signature, find_defaults); 1563 } 1564 return m; 1565 } 1566 1567 // lookup a method in all the interfaces that this class implements 1568 // Do NOT return private or static methods, new in JDK8 which are not externally visible 1569 // They should only be found in the initial InterfaceMethodRef 1570 Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name, 1571 Symbol* signature, 1572 DefaultsLookupMode defaults_mode) const { 1573 Array<Klass*>* all_ifs = transitive_interfaces(); 1574 int num_ifs = all_ifs->length(); 1575 InstanceKlass *ik = NULL; 1576 for (int i = 0; i < num_ifs; i++) { 1577 ik = InstanceKlass::cast(all_ifs->at(i)); 1578 Method* m = ik->lookup_method(name, signature); 1579 if (m != NULL && m->is_public() && !m->is_static() && 1580 ((defaults_mode != skip_defaults) || !m->is_default_method())) { 1581 return m; 1582 } 1583 } 1584 return NULL; 1585 } 1586 1587 /* jni_id_for_impl for jfieldIds only */ 1588 JNIid* InstanceKlass::jni_id_for_impl(instanceKlassHandle this_k, int offset) { 1589 MutexLocker ml(JfieldIdCreation_lock); 1590 // Retry lookup after we got the lock 1591 JNIid* probe = this_k->jni_ids() == NULL ? NULL : this_k->jni_ids()->find(offset); 1592 if (probe == NULL) { 1593 // Slow case, allocate new static field identifier 1594 probe = new JNIid(this_k(), offset, this_k->jni_ids()); 1595 this_k->set_jni_ids(probe); 1596 } 1597 return probe; 1598 } 1599 1600 1601 /* jni_id_for for jfieldIds only */ 1602 JNIid* InstanceKlass::jni_id_for(int offset) { 1603 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset); 1604 if (probe == NULL) { 1605 probe = jni_id_for_impl(this, offset); 1606 } 1607 return probe; 1608 } 1609 1610 u2 InstanceKlass::enclosing_method_data(int offset) { 1611 Array<jushort>* inner_class_list = inner_classes(); 1612 if (inner_class_list == NULL) { 1613 return 0; 1614 } 1615 int length = inner_class_list->length(); 1616 if (length % inner_class_next_offset == 0) { 1617 return 0; 1618 } else { 1619 int index = length - enclosing_method_attribute_size; 1620 assert(offset < enclosing_method_attribute_size, "invalid offset"); 1621 return inner_class_list->at(index + offset); 1622 } 1623 } 1624 1625 void InstanceKlass::set_enclosing_method_indices(u2 class_index, 1626 u2 method_index) { 1627 Array<jushort>* inner_class_list = inner_classes(); 1628 assert (inner_class_list != NULL, "_inner_classes list is not set up"); 1629 int length = inner_class_list->length(); 1630 if (length % inner_class_next_offset == enclosing_method_attribute_size) { 1631 int index = length - enclosing_method_attribute_size; 1632 inner_class_list->at_put( 1633 index + enclosing_method_class_index_offset, class_index); 1634 inner_class_list->at_put( 1635 index + enclosing_method_method_index_offset, method_index); 1636 } 1637 } 1638 1639 // Lookup or create a jmethodID. 1640 // This code is called by the VMThread and JavaThreads so the 1641 // locking has to be done very carefully to avoid deadlocks 1642 // and/or other cache consistency problems. 1643 // 1644 jmethodID InstanceKlass::get_jmethod_id(instanceKlassHandle ik_h, methodHandle method_h) { 1645 size_t idnum = (size_t)method_h->method_idnum(); 1646 jmethodID* jmeths = ik_h->methods_jmethod_ids_acquire(); 1647 size_t length = 0; 1648 jmethodID id = NULL; 1649 1650 // We use a double-check locking idiom here because this cache is 1651 // performance sensitive. In the normal system, this cache only 1652 // transitions from NULL to non-NULL which is safe because we use 1653 // release_set_methods_jmethod_ids() to advertise the new cache. 1654 // A partially constructed cache should never be seen by a racing 1655 // thread. We also use release_store_ptr() to save a new jmethodID 1656 // in the cache so a partially constructed jmethodID should never be 1657 // seen either. Cache reads of existing jmethodIDs proceed without a 1658 // lock, but cache writes of a new jmethodID requires uniqueness and 1659 // creation of the cache itself requires no leaks so a lock is 1660 // generally acquired in those two cases. 1661 // 1662 // If the RedefineClasses() API has been used, then this cache can 1663 // grow and we'll have transitions from non-NULL to bigger non-NULL. 1664 // Cache creation requires no leaks and we require safety between all 1665 // cache accesses and freeing of the old cache so a lock is generally 1666 // acquired when the RedefineClasses() API has been used. 1667 1668 if (jmeths != NULL) { 1669 // the cache already exists 1670 if (!ik_h->idnum_can_increment()) { 1671 // the cache can't grow so we can just get the current values 1672 get_jmethod_id_length_value(jmeths, idnum, &length, &id); 1673 } else { 1674 // cache can grow so we have to be more careful 1675 if (Threads::number_of_threads() == 0 || 1676 SafepointSynchronize::is_at_safepoint()) { 1677 // we're single threaded or at a safepoint - no locking needed 1678 get_jmethod_id_length_value(jmeths, idnum, &length, &id); 1679 } else { 1680 MutexLocker ml(JmethodIdCreation_lock); 1681 get_jmethod_id_length_value(jmeths, idnum, &length, &id); 1682 } 1683 } 1684 } 1685 // implied else: 1686 // we need to allocate a cache so default length and id values are good 1687 1688 if (jmeths == NULL || // no cache yet 1689 length <= idnum || // cache is too short 1690 id == NULL) { // cache doesn't contain entry 1691 1692 // This function can be called by the VMThread so we have to do all 1693 // things that might block on a safepoint before grabbing the lock. 1694 // Otherwise, we can deadlock with the VMThread or have a cache 1695 // consistency issue. These vars keep track of what we might have 1696 // to free after the lock is dropped. 1697 jmethodID to_dealloc_id = NULL; 1698 jmethodID* to_dealloc_jmeths = NULL; 1699 1700 // may not allocate new_jmeths or use it if we allocate it 1701 jmethodID* new_jmeths = NULL; 1702 if (length <= idnum) { 1703 // allocate a new cache that might be used 1704 size_t size = MAX2(idnum+1, (size_t)ik_h->idnum_allocated_count()); 1705 new_jmeths = NEW_C_HEAP_ARRAY(jmethodID, size+1, mtClass); 1706 memset(new_jmeths, 0, (size+1)*sizeof(jmethodID)); 1707 // cache size is stored in element[0], other elements offset by one 1708 new_jmeths[0] = (jmethodID)size; 1709 } 1710 1711 // allocate a new jmethodID that might be used 1712 jmethodID new_id = NULL; 1713 if (method_h->is_old() && !method_h->is_obsolete()) { 1714 // The method passed in is old (but not obsolete), we need to use the current version 1715 Method* current_method = ik_h->method_with_idnum((int)idnum); 1716 assert(current_method != NULL, "old and but not obsolete, so should exist"); 1717 new_id = Method::make_jmethod_id(ik_h->class_loader_data(), current_method); 1718 } else { 1719 // It is the current version of the method or an obsolete method, 1720 // use the version passed in 1721 new_id = Method::make_jmethod_id(ik_h->class_loader_data(), method_h()); 1722 } 1723 1724 if (Threads::number_of_threads() == 0 || 1725 SafepointSynchronize::is_at_safepoint()) { 1726 // we're single threaded or at a safepoint - no locking needed 1727 id = get_jmethod_id_fetch_or_update(ik_h, idnum, new_id, new_jmeths, 1728 &to_dealloc_id, &to_dealloc_jmeths); 1729 } else { 1730 MutexLocker ml(JmethodIdCreation_lock); 1731 id = get_jmethod_id_fetch_or_update(ik_h, idnum, new_id, new_jmeths, 1732 &to_dealloc_id, &to_dealloc_jmeths); 1733 } 1734 1735 // The lock has been dropped so we can free resources. 1736 // Free up either the old cache or the new cache if we allocated one. 1737 if (to_dealloc_jmeths != NULL) { 1738 FreeHeap(to_dealloc_jmeths); 1739 } 1740 // free up the new ID since it wasn't needed 1741 if (to_dealloc_id != NULL) { 1742 Method::destroy_jmethod_id(ik_h->class_loader_data(), to_dealloc_id); 1743 } 1744 } 1745 return id; 1746 } 1747 1748 // Figure out how many jmethodIDs haven't been allocated, and make 1749 // sure space for them is pre-allocated. This makes getting all 1750 // method ids much, much faster with classes with more than 8 1751 // methods, and has a *substantial* effect on performance with jvmti 1752 // code that loads all jmethodIDs for all classes. 1753 void InstanceKlass::ensure_space_for_methodids(int start_offset) { 1754 int new_jmeths = 0; 1755 int length = methods()->length(); 1756 for (int index = start_offset; index < length; index++) { 1757 Method* m = methods()->at(index); 1758 jmethodID id = m->find_jmethod_id_or_null(); 1759 if (id == NULL) { 1760 new_jmeths++; 1761 } 1762 } 1763 if (new_jmeths != 0) { 1764 Method::ensure_jmethod_ids(class_loader_data(), new_jmeths); 1765 } 1766 } 1767 1768 // Common code to fetch the jmethodID from the cache or update the 1769 // cache with the new jmethodID. This function should never do anything 1770 // that causes the caller to go to a safepoint or we can deadlock with 1771 // the VMThread or have cache consistency issues. 1772 // 1773 jmethodID InstanceKlass::get_jmethod_id_fetch_or_update( 1774 instanceKlassHandle ik_h, size_t idnum, jmethodID new_id, 1775 jmethodID* new_jmeths, jmethodID* to_dealloc_id_p, 1776 jmethodID** to_dealloc_jmeths_p) { 1777 assert(new_id != NULL, "sanity check"); 1778 assert(to_dealloc_id_p != NULL, "sanity check"); 1779 assert(to_dealloc_jmeths_p != NULL, "sanity check"); 1780 assert(Threads::number_of_threads() == 0 || 1781 SafepointSynchronize::is_at_safepoint() || 1782 JmethodIdCreation_lock->owned_by_self(), "sanity check"); 1783 1784 // reacquire the cache - we are locked, single threaded or at a safepoint 1785 jmethodID* jmeths = ik_h->methods_jmethod_ids_acquire(); 1786 jmethodID id = NULL; 1787 size_t length = 0; 1788 1789 if (jmeths == NULL || // no cache yet 1790 (length = (size_t)jmeths[0]) <= idnum) { // cache is too short 1791 if (jmeths != NULL) { 1792 // copy any existing entries from the old cache 1793 for (size_t index = 0; index < length; index++) { 1794 new_jmeths[index+1] = jmeths[index+1]; 1795 } 1796 *to_dealloc_jmeths_p = jmeths; // save old cache for later delete 1797 } 1798 ik_h->release_set_methods_jmethod_ids(jmeths = new_jmeths); 1799 } else { 1800 // fetch jmethodID (if any) from the existing cache 1801 id = jmeths[idnum+1]; 1802 *to_dealloc_jmeths_p = new_jmeths; // save new cache for later delete 1803 } 1804 if (id == NULL) { 1805 // No matching jmethodID in the existing cache or we have a new 1806 // cache or we just grew the cache. This cache write is done here 1807 // by the first thread to win the foot race because a jmethodID 1808 // needs to be unique once it is generally available. 1809 id = new_id; 1810 1811 // The jmethodID cache can be read while unlocked so we have to 1812 // make sure the new jmethodID is complete before installing it 1813 // in the cache. 1814 OrderAccess::release_store_ptr(&jmeths[idnum+1], id); 1815 } else { 1816 *to_dealloc_id_p = new_id; // save new id for later delete 1817 } 1818 return id; 1819 } 1820 1821 1822 // Common code to get the jmethodID cache length and the jmethodID 1823 // value at index idnum if there is one. 1824 // 1825 void InstanceKlass::get_jmethod_id_length_value(jmethodID* cache, 1826 size_t idnum, size_t *length_p, jmethodID* id_p) { 1827 assert(cache != NULL, "sanity check"); 1828 assert(length_p != NULL, "sanity check"); 1829 assert(id_p != NULL, "sanity check"); 1830 1831 // cache size is stored in element[0], other elements offset by one 1832 *length_p = (size_t)cache[0]; 1833 if (*length_p <= idnum) { // cache is too short 1834 *id_p = NULL; 1835 } else { 1836 *id_p = cache[idnum+1]; // fetch jmethodID (if any) 1837 } 1838 } 1839 1840 1841 // Lookup a jmethodID, NULL if not found. Do no blocking, no allocations, no handles 1842 jmethodID InstanceKlass::jmethod_id_or_null(Method* method) { 1843 size_t idnum = (size_t)method->method_idnum(); 1844 jmethodID* jmeths = methods_jmethod_ids_acquire(); 1845 size_t length; // length assigned as debugging crumb 1846 jmethodID id = NULL; 1847 if (jmeths != NULL && // If there is a cache 1848 (length = (size_t)jmeths[0]) > idnum) { // and if it is long enough, 1849 id = jmeths[idnum+1]; // Look up the id (may be NULL) 1850 } 1851 return id; 1852 } 1853 1854 int nmethodBucket::decrement() { 1855 return Atomic::add(-1, (volatile int *)&_count); 1856 } 1857 1858 // 1859 // Walk the list of dependent nmethods searching for nmethods which 1860 // are dependent on the changes that were passed in and mark them for 1861 // deoptimization. Returns the number of nmethods found. 1862 // 1863 int InstanceKlass::mark_dependent_nmethods(DepChange& changes) { 1864 assert_locked_or_safepoint(CodeCache_lock); 1865 int found = 0; 1866 nmethodBucket* b = _dependencies; 1867 while (b != NULL) { 1868 nmethod* nm = b->get_nmethod(); 1869 // since dependencies aren't removed until an nmethod becomes a zombie, 1870 // the dependency list may contain nmethods which aren't alive. 1871 if (b->count() > 0 && nm->is_alive() && !nm->is_marked_for_deoptimization() && nm->check_dependency_on(changes)) { 1872 if (TraceDependencies) { 1873 ResourceMark rm; 1874 tty->print_cr("Marked for deoptimization"); 1875 tty->print_cr(" context = %s", this->external_name()); 1876 changes.print(); 1877 nm->print(); 1878 nm->print_dependencies(); 1879 } 1880 nm->mark_for_deoptimization(); 1881 found++; 1882 } 1883 b = b->next(); 1884 } 1885 return found; 1886 } 1887 1888 void InstanceKlass::clean_dependent_nmethods() { 1889 assert_locked_or_safepoint(CodeCache_lock); 1890 1891 if (has_unloaded_dependent()) { 1892 nmethodBucket* b = _dependencies; 1893 nmethodBucket* last = NULL; 1894 while (b != NULL) { 1895 assert(b->count() >= 0, err_msg("bucket count: %d", b->count())); 1896 1897 nmethodBucket* next = b->next(); 1898 1899 if (b->count() == 0) { 1900 if (last == NULL) { 1901 _dependencies = next; 1902 } else { 1903 last->set_next(next); 1904 } 1905 delete b; 1906 // last stays the same. 1907 } else { 1908 last = b; 1909 } 1910 1911 b = next; 1912 } 1913 set_has_unloaded_dependent(false); 1914 } 1915 #ifdef ASSERT 1916 else { 1917 // Verification 1918 for (nmethodBucket* b = _dependencies; b != NULL; b = b->next()) { 1919 assert(b->count() >= 0, err_msg("bucket count: %d", b->count())); 1920 assert(b->count() != 0, "empty buckets need to be cleaned"); 1921 } 1922 } 1923 #endif 1924 } 1925 1926 // 1927 // Add an nmethodBucket to the list of dependencies for this nmethod. 1928 // It's possible that an nmethod has multiple dependencies on this klass 1929 // so a count is kept for each bucket to guarantee that creation and 1930 // deletion of dependencies is consistent. 1931 // 1932 void InstanceKlass::add_dependent_nmethod(nmethod* nm) { 1933 assert_locked_or_safepoint(CodeCache_lock); 1934 nmethodBucket* b = _dependencies; 1935 nmethodBucket* last = NULL; 1936 while (b != NULL) { 1937 if (nm == b->get_nmethod()) { 1938 b->increment(); 1939 return; 1940 } 1941 b = b->next(); 1942 } 1943 _dependencies = new nmethodBucket(nm, _dependencies); 1944 } 1945 1946 1947 // 1948 // Decrement count of the nmethod in the dependency list and remove 1949 // the bucket competely when the count goes to 0. This method must 1950 // find a corresponding bucket otherwise there's a bug in the 1951 // recording of dependecies. 1952 // 1953 void InstanceKlass::remove_dependent_nmethod(nmethod* nm) { 1954 assert_locked_or_safepoint(CodeCache_lock); 1955 nmethodBucket* b = _dependencies; 1956 nmethodBucket* last = NULL; 1957 while (b != NULL) { 1958 if (nm == b->get_nmethod()) { 1959 int val = b->decrement(); 1960 guarantee(val >= 0, err_msg("Underflow: %d", val)); 1961 if (val == 0) { 1962 set_has_unloaded_dependent(true); 1963 } 1964 return; 1965 } 1966 last = b; 1967 b = b->next(); 1968 } 1969 #ifdef ASSERT 1970 tty->print_cr("### %s can't find dependent nmethod:", this->external_name()); 1971 nm->print(); 1972 #endif // ASSERT 1973 ShouldNotReachHere(); 1974 } 1975 1976 1977 #ifndef PRODUCT 1978 void InstanceKlass::print_dependent_nmethods(bool verbose) { 1979 nmethodBucket* b = _dependencies; 1980 int idx = 0; 1981 while (b != NULL) { 1982 nmethod* nm = b->get_nmethod(); 1983 tty->print("[%d] count=%d { ", idx++, b->count()); 1984 if (!verbose) { 1985 nm->print_on(tty, "nmethod"); 1986 tty->print_cr(" } "); 1987 } else { 1988 nm->print(); 1989 nm->print_dependencies(); 1990 tty->print_cr("--- } "); 1991 } 1992 b = b->next(); 1993 } 1994 } 1995 1996 1997 bool InstanceKlass::is_dependent_nmethod(nmethod* nm) { 1998 nmethodBucket* b = _dependencies; 1999 while (b != NULL) { 2000 if (nm == b->get_nmethod()) { 2001 #ifdef ASSERT 2002 int count = b->count(); 2003 assert(count >= 0, err_msg("count shouldn't be negative: %d", count)); 2004 #endif 2005 return true; 2006 } 2007 b = b->next(); 2008 } 2009 return false; 2010 } 2011 #endif //PRODUCT 2012 2013 2014 // Garbage collection 2015 2016 #ifdef ASSERT 2017 template <class T> void assert_is_in(T *p) { 2018 T heap_oop = oopDesc::load_heap_oop(p); 2019 if (!oopDesc::is_null(heap_oop)) { 2020 oop o = oopDesc::decode_heap_oop_not_null(heap_oop); 2021 assert(Universe::heap()->is_in(o), "should be in heap"); 2022 } 2023 } 2024 template <class T> void assert_is_in_closed_subset(T *p) { 2025 T heap_oop = oopDesc::load_heap_oop(p); 2026 if (!oopDesc::is_null(heap_oop)) { 2027 oop o = oopDesc::decode_heap_oop_not_null(heap_oop); 2028 assert(Universe::heap()->is_in_closed_subset(o), 2029 err_msg("should be in closed *p " INTPTR_FORMAT " " INTPTR_FORMAT, (address)p, (address)o)); 2030 } 2031 } 2032 template <class T> void assert_is_in_reserved(T *p) { 2033 T heap_oop = oopDesc::load_heap_oop(p); 2034 if (!oopDesc::is_null(heap_oop)) { 2035 oop o = oopDesc::decode_heap_oop_not_null(heap_oop); 2036 assert(Universe::heap()->is_in_reserved(o), "should be in reserved"); 2037 } 2038 } 2039 template <class T> void assert_nothing(T *p) {} 2040 2041 #else 2042 template <class T> void assert_is_in(T *p) {} 2043 template <class T> void assert_is_in_closed_subset(T *p) {} 2044 template <class T> void assert_is_in_reserved(T *p) {} 2045 template <class T> void assert_nothing(T *p) {} 2046 #endif // ASSERT 2047 2048 // 2049 // Macros that iterate over areas of oops which are specialized on type of 2050 // oop pointer either narrow or wide, depending on UseCompressedOops 2051 // 2052 // Parameters are: 2053 // T - type of oop to point to (either oop or narrowOop) 2054 // start_p - starting pointer for region to iterate over 2055 // count - number of oops or narrowOops to iterate over 2056 // do_oop - action to perform on each oop (it's arbitrary C code which 2057 // makes it more efficient to put in a macro rather than making 2058 // it a template function) 2059 // assert_fn - assert function which is template function because performance 2060 // doesn't matter when enabled. 2061 #define InstanceKlass_SPECIALIZED_OOP_ITERATE( \ 2062 T, start_p, count, do_oop, \ 2063 assert_fn) \ 2064 { \ 2065 T* p = (T*)(start_p); \ 2066 T* const end = p + (count); \ 2067 while (p < end) { \ 2068 (assert_fn)(p); \ 2069 do_oop; \ 2070 ++p; \ 2071 } \ 2072 } 2073 2074 #define InstanceKlass_SPECIALIZED_OOP_REVERSE_ITERATE( \ 2075 T, start_p, count, do_oop, \ 2076 assert_fn) \ 2077 { \ 2078 T* const start = (T*)(start_p); \ 2079 T* p = start + (count); \ 2080 while (start < p) { \ 2081 --p; \ 2082 (assert_fn)(p); \ 2083 do_oop; \ 2084 } \ 2085 } 2086 2087 #define InstanceKlass_SPECIALIZED_BOUNDED_OOP_ITERATE( \ 2088 T, start_p, count, low, high, \ 2089 do_oop, assert_fn) \ 2090 { \ 2091 T* const l = (T*)(low); \ 2092 T* const h = (T*)(high); \ 2093 assert(mask_bits((intptr_t)l, sizeof(T)-1) == 0 && \ 2094 mask_bits((intptr_t)h, sizeof(T)-1) == 0, \ 2095 "bounded region must be properly aligned"); \ 2096 T* p = (T*)(start_p); \ 2097 T* end = p + (count); \ 2098 if (p < l) p = l; \ 2099 if (end > h) end = h; \ 2100 while (p < end) { \ 2101 (assert_fn)(p); \ 2102 do_oop; \ 2103 ++p; \ 2104 } \ 2105 } 2106 2107 2108 // The following macros call specialized macros, passing either oop or 2109 // narrowOop as the specialization type. These test the UseCompressedOops 2110 // flag. 2111 #define InstanceKlass_OOP_MAP_ITERATE(obj, do_oop, assert_fn) \ 2112 { \ 2113 /* Compute oopmap block range. The common case \ 2114 is nonstatic_oop_map_size == 1. */ \ 2115 OopMapBlock* map = start_of_nonstatic_oop_maps(); \ 2116 OopMapBlock* const end_map = map + nonstatic_oop_map_count(); \ 2117 if (UseCompressedOops) { \ 2118 while (map < end_map) { \ 2119 InstanceKlass_SPECIALIZED_OOP_ITERATE(narrowOop, \ 2120 obj->obj_field_addr<narrowOop>(map->offset()), map->count(), \ 2121 do_oop, assert_fn) \ 2122 ++map; \ 2123 } \ 2124 } else { \ 2125 while (map < end_map) { \ 2126 InstanceKlass_SPECIALIZED_OOP_ITERATE(oop, \ 2127 obj->obj_field_addr<oop>(map->offset()), map->count(), \ 2128 do_oop, assert_fn) \ 2129 ++map; \ 2130 } \ 2131 } \ 2132 } 2133 2134 #define InstanceKlass_OOP_MAP_REVERSE_ITERATE(obj, do_oop, assert_fn) \ 2135 { \ 2136 OopMapBlock* const start_map = start_of_nonstatic_oop_maps(); \ 2137 OopMapBlock* map = start_map + nonstatic_oop_map_count(); \ 2138 if (UseCompressedOops) { \ 2139 while (start_map < map) { \ 2140 --map; \ 2141 InstanceKlass_SPECIALIZED_OOP_REVERSE_ITERATE(narrowOop, \ 2142 obj->obj_field_addr<narrowOop>(map->offset()), map->count(), \ 2143 do_oop, assert_fn) \ 2144 } \ 2145 } else { \ 2146 while (start_map < map) { \ 2147 --map; \ 2148 InstanceKlass_SPECIALIZED_OOP_REVERSE_ITERATE(oop, \ 2149 obj->obj_field_addr<oop>(map->offset()), map->count(), \ 2150 do_oop, assert_fn) \ 2151 } \ 2152 } \ 2153 } 2154 2155 #define InstanceKlass_BOUNDED_OOP_MAP_ITERATE(obj, low, high, do_oop, \ 2156 assert_fn) \ 2157 { \ 2158 /* Compute oopmap block range. The common case is \ 2159 nonstatic_oop_map_size == 1, so we accept the \ 2160 usually non-existent extra overhead of examining \ 2161 all the maps. */ \ 2162 OopMapBlock* map = start_of_nonstatic_oop_maps(); \ 2163 OopMapBlock* const end_map = map + nonstatic_oop_map_count(); \ 2164 if (UseCompressedOops) { \ 2165 while (map < end_map) { \ 2166 InstanceKlass_SPECIALIZED_BOUNDED_OOP_ITERATE(narrowOop, \ 2167 obj->obj_field_addr<narrowOop>(map->offset()), map->count(), \ 2168 low, high, \ 2169 do_oop, assert_fn) \ 2170 ++map; \ 2171 } \ 2172 } else { \ 2173 while (map < end_map) { \ 2174 InstanceKlass_SPECIALIZED_BOUNDED_OOP_ITERATE(oop, \ 2175 obj->obj_field_addr<oop>(map->offset()), map->count(), \ 2176 low, high, \ 2177 do_oop, assert_fn) \ 2178 ++map; \ 2179 } \ 2180 } \ 2181 } 2182 2183 void InstanceKlass::oop_follow_contents(oop obj) { 2184 assert(obj != NULL, "can't follow the content of NULL object"); 2185 MarkSweep::follow_klass(obj->klass()); 2186 InstanceKlass_OOP_MAP_ITERATE( \ 2187 obj, \ 2188 MarkSweep::mark_and_push(p), \ 2189 assert_is_in_closed_subset) 2190 } 2191 2192 #if INCLUDE_ALL_GCS 2193 void InstanceKlass::oop_follow_contents(ParCompactionManager* cm, 2194 oop obj) { 2195 assert(obj != NULL, "can't follow the content of NULL object"); 2196 PSParallelCompact::follow_klass(cm, obj->klass()); 2197 // Only mark the header and let the scan of the meta-data mark 2198 // everything else. 2199 InstanceKlass_OOP_MAP_ITERATE( \ 2200 obj, \ 2201 PSParallelCompact::mark_and_push(cm, p), \ 2202 assert_is_in) 2203 } 2204 #endif // INCLUDE_ALL_GCS 2205 2206 // closure's do_metadata() method dictates whether the given closure should be 2207 // applied to the klass ptr in the object header. 2208 2209 #define InstanceKlass_OOP_OOP_ITERATE_DEFN(OopClosureType, nv_suffix) \ 2210 \ 2211 int InstanceKlass::oop_oop_iterate##nv_suffix(oop obj, OopClosureType* closure) { \ 2212 /* header */ \ 2213 if_do_metadata_checked(closure, nv_suffix) { \ 2214 closure->do_klass##nv_suffix(obj->klass()); \ 2215 } \ 2216 InstanceKlass_OOP_MAP_ITERATE( \ 2217 obj, \ 2218 (closure)->do_oop##nv_suffix(p), \ 2219 assert_is_in_closed_subset) \ 2220 return size_helper(); \ 2221 } 2222 2223 #if INCLUDE_ALL_GCS 2224 #define InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DEFN(OopClosureType, nv_suffix) \ 2225 \ 2226 int InstanceKlass::oop_oop_iterate_backwards##nv_suffix(oop obj, \ 2227 OopClosureType* closure) { \ 2228 assert_should_ignore_metadata(closure, nv_suffix); \ 2229 \ 2230 /* instance variables */ \ 2231 InstanceKlass_OOP_MAP_REVERSE_ITERATE( \ 2232 obj, \ 2233 (closure)->do_oop##nv_suffix(p), \ 2234 assert_is_in_closed_subset) \ 2235 return size_helper(); \ 2236 } 2237 #endif // INCLUDE_ALL_GCS 2238 2239 #define InstanceKlass_OOP_OOP_ITERATE_DEFN_m(OopClosureType, nv_suffix) \ 2240 \ 2241 int InstanceKlass::oop_oop_iterate##nv_suffix##_m(oop obj, \ 2242 OopClosureType* closure, \ 2243 MemRegion mr) { \ 2244 if_do_metadata_checked(closure, nv_suffix) { \ 2245 if (mr.contains(obj)) { \ 2246 closure->do_klass##nv_suffix(obj->klass()); \ 2247 } \ 2248 } \ 2249 InstanceKlass_BOUNDED_OOP_MAP_ITERATE( \ 2250 obj, mr.start(), mr.end(), \ 2251 (closure)->do_oop##nv_suffix(p), \ 2252 assert_is_in_closed_subset) \ 2253 return size_helper(); \ 2254 } 2255 2256 ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_DEFN) 2257 ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceKlass_OOP_OOP_ITERATE_DEFN) 2258 ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_DEFN_m) 2259 ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceKlass_OOP_OOP_ITERATE_DEFN_m) 2260 #if INCLUDE_ALL_GCS 2261 ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DEFN) 2262 ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DEFN) 2263 #endif // INCLUDE_ALL_GCS 2264 2265 int InstanceKlass::oop_adjust_pointers(oop obj) { 2266 int size = size_helper(); 2267 InstanceKlass_OOP_MAP_ITERATE( \ 2268 obj, \ 2269 MarkSweep::adjust_pointer(p), \ 2270 assert_is_in) 2271 return size; 2272 } 2273 2274 #if INCLUDE_ALL_GCS 2275 void InstanceKlass::oop_push_contents(PSPromotionManager* pm, oop obj) { 2276 InstanceKlass_OOP_MAP_REVERSE_ITERATE( \ 2277 obj, \ 2278 if (PSScavenge::should_scavenge(p)) { \ 2279 pm->claim_or_forward_depth(p); \ 2280 }, \ 2281 assert_nothing ) 2282 } 2283 2284 int InstanceKlass::oop_update_pointers(ParCompactionManager* cm, oop obj) { 2285 int size = size_helper(); 2286 InstanceKlass_OOP_MAP_ITERATE( \ 2287 obj, \ 2288 PSParallelCompact::adjust_pointer(p), \ 2289 assert_is_in) 2290 return size; 2291 } 2292 2293 #endif // INCLUDE_ALL_GCS 2294 2295 void InstanceKlass::clean_implementors_list(BoolObjectClosure* is_alive) { 2296 assert(class_loader_data()->is_alive(is_alive), "this klass should be live"); 2297 if (is_interface()) { 2298 if (ClassUnloading) { 2299 Klass* impl = implementor(); 2300 if (impl != NULL) { 2301 if (!impl->is_loader_alive(is_alive)) { 2302 // remove this guy 2303 Klass** klass = adr_implementor(); 2304 assert(klass != NULL, "null klass"); 2305 if (klass != NULL) { 2306 *klass = NULL; 2307 } 2308 } 2309 } 2310 } 2311 } 2312 } 2313 2314 void InstanceKlass::clean_method_data(BoolObjectClosure* is_alive) { 2315 for (int m = 0; m < methods()->length(); m++) { 2316 MethodData* mdo = methods()->at(m)->method_data(); 2317 if (mdo != NULL) { 2318 mdo->clean_method_data(is_alive); 2319 } 2320 } 2321 } 2322 2323 2324 static void remove_unshareable_in_class(Klass* k) { 2325 // remove klass's unshareable info 2326 k->remove_unshareable_info(); 2327 } 2328 2329 void InstanceKlass::remove_unshareable_info() { 2330 Klass::remove_unshareable_info(); 2331 // Unlink the class 2332 if (is_linked()) { 2333 unlink_class(); 2334 } 2335 init_implementor(); 2336 2337 constants()->remove_unshareable_info(); 2338 2339 for (int i = 0; i < methods()->length(); i++) { 2340 Method* m = methods()->at(i); 2341 m->remove_unshareable_info(); 2342 } 2343 2344 // do array classes also. 2345 array_klasses_do(remove_unshareable_in_class); 2346 } 2347 2348 static void restore_unshareable_in_class(Klass* k, TRAPS) { 2349 // Array classes have null protection domain. 2350 // --> see ArrayKlass::complete_create_array_klass() 2351 k->restore_unshareable_info(ClassLoaderData::the_null_class_loader_data(), Handle(), CHECK); 2352 } 2353 2354 void InstanceKlass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain, TRAPS) { 2355 Klass::restore_unshareable_info(loader_data, protection_domain, CHECK); 2356 instanceKlassHandle ik(THREAD, this); 2357 2358 Array<Method*>* methods = ik->methods(); 2359 int num_methods = methods->length(); 2360 for (int index2 = 0; index2 < num_methods; ++index2) { 2361 methodHandle m(THREAD, methods->at(index2)); 2362 m->restore_unshareable_info(CHECK); 2363 } 2364 if (JvmtiExport::has_redefined_a_class()) { 2365 // Reinitialize vtable because RedefineClasses may have changed some 2366 // entries in this vtable for super classes so the CDS vtable might 2367 // point to old or obsolete entries. RedefineClasses doesn't fix up 2368 // vtables in the shared system dictionary, only the main one. 2369 // It also redefines the itable too so fix that too. 2370 ResourceMark rm(THREAD); 2371 ik->vtable()->initialize_vtable(false, CHECK); 2372 ik->itable()->initialize_itable(false, CHECK); 2373 } 2374 2375 // restore constant pool resolved references 2376 ik->constants()->restore_unshareable_info(CHECK); 2377 2378 ik->array_klasses_do(restore_unshareable_in_class, CHECK); 2379 } 2380 2381 // returns true IFF is_in_error_state() has been changed as a result of this call. 2382 bool InstanceKlass::check_sharing_error_state() { 2383 assert(DumpSharedSpaces, "should only be called during dumping"); 2384 bool old_state = is_in_error_state(); 2385 2386 if (!is_in_error_state()) { 2387 bool bad = false; 2388 for (InstanceKlass* sup = java_super(); sup; sup = sup->java_super()) { 2389 if (sup->is_in_error_state()) { 2390 bad = true; 2391 break; 2392 } 2393 } 2394 if (!bad) { 2395 Array<Klass*>* interfaces = transitive_interfaces(); 2396 for (int i = 0; i < interfaces->length(); i++) { 2397 Klass* iface = interfaces->at(i); 2398 if (InstanceKlass::cast(iface)->is_in_error_state()) { 2399 bad = true; 2400 break; 2401 } 2402 } 2403 } 2404 2405 if (bad) { 2406 set_in_error_state(); 2407 } 2408 } 2409 2410 return (old_state != is_in_error_state()); 2411 } 2412 2413 static void clear_all_breakpoints(Method* m) { 2414 m->clear_all_breakpoints(); 2415 } 2416 2417 2418 void InstanceKlass::notify_unload_class(InstanceKlass* ik) { 2419 // notify the debugger 2420 if (JvmtiExport::should_post_class_unload()) { 2421 JvmtiExport::post_class_unload(ik); 2422 } 2423 2424 // notify ClassLoadingService of class unload 2425 ClassLoadingService::notify_class_unloaded(ik); 2426 } 2427 2428 void InstanceKlass::release_C_heap_structures(InstanceKlass* ik) { 2429 // Clean up C heap 2430 ik->release_C_heap_structures(); 2431 ik->constants()->release_C_heap_structures(); 2432 } 2433 2434 void InstanceKlass::release_C_heap_structures() { 2435 2436 // Can't release the constant pool here because the constant pool can be 2437 // deallocated separately from the InstanceKlass for default methods and 2438 // redefine classes. 2439 2440 // Deallocate oop map cache 2441 if (_oop_map_cache != NULL) { 2442 delete _oop_map_cache; 2443 _oop_map_cache = NULL; 2444 } 2445 2446 // Deallocate JNI identifiers for jfieldIDs 2447 JNIid::deallocate(jni_ids()); 2448 set_jni_ids(NULL); 2449 2450 jmethodID* jmeths = methods_jmethod_ids_acquire(); 2451 if (jmeths != (jmethodID*)NULL) { 2452 release_set_methods_jmethod_ids(NULL); 2453 FreeHeap(jmeths); 2454 } 2455 2456 // Deallocate MemberNameTable 2457 { 2458 Mutex* lock_or_null = SafepointSynchronize::is_at_safepoint() ? NULL : MemberNameTable_lock; 2459 MutexLockerEx ml(lock_or_null, Mutex::_no_safepoint_check_flag); 2460 MemberNameTable* mnt = member_names(); 2461 if (mnt != NULL) { 2462 delete mnt; 2463 set_member_names(NULL); 2464 } 2465 } 2466 2467 // release dependencies 2468 nmethodBucket* b = _dependencies; 2469 _dependencies = NULL; 2470 while (b != NULL) { 2471 nmethodBucket* next = b->next(); 2472 delete b; 2473 b = next; 2474 } 2475 2476 // Deallocate breakpoint records 2477 if (breakpoints() != 0x0) { 2478 methods_do(clear_all_breakpoints); 2479 assert(breakpoints() == 0x0, "should have cleared breakpoints"); 2480 } 2481 2482 // deallocate the cached class file 2483 if (_cached_class_file != NULL) { 2484 os::free(_cached_class_file); 2485 _cached_class_file = NULL; 2486 } 2487 2488 // Decrement symbol reference counts associated with the unloaded class. 2489 if (_name != NULL) _name->decrement_refcount(); 2490 // unreference array name derived from this class name (arrays of an unloaded 2491 // class can't be referenced anymore). 2492 if (_array_name != NULL) _array_name->decrement_refcount(); 2493 if (_source_debug_extension != NULL) FREE_C_HEAP_ARRAY(char, _source_debug_extension); 2494 2495 assert(_total_instanceKlass_count >= 1, "Sanity check"); 2496 Atomic::dec(&_total_instanceKlass_count); 2497 } 2498 2499 void InstanceKlass::set_source_debug_extension(char* array, int length) { 2500 if (array == NULL) { 2501 _source_debug_extension = NULL; 2502 } else { 2503 // Adding one to the attribute length in order to store a null terminator 2504 // character could cause an overflow because the attribute length is 2505 // already coded with an u4 in the classfile, but in practice, it's 2506 // unlikely to happen. 2507 assert((length+1) > length, "Overflow checking"); 2508 char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass); 2509 for (int i = 0; i < length; i++) { 2510 sde[i] = array[i]; 2511 } 2512 sde[length] = '\0'; 2513 _source_debug_extension = sde; 2514 } 2515 } 2516 2517 address InstanceKlass::static_field_addr(int offset) { 2518 return (address)(offset + InstanceMirrorKlass::offset_of_static_fields() + cast_from_oop<intptr_t>(java_mirror())); 2519 } 2520 2521 2522 const char* InstanceKlass::signature_name() const { 2523 int hash_len = 0; 2524 char hash_buf[40]; 2525 2526 // If this is an anonymous class, append a hash to make the name unique 2527 if (is_anonymous()) { 2528 intptr_t hash = (java_mirror() != NULL) ? java_mirror()->identity_hash() : 0; 2529 jio_snprintf(hash_buf, sizeof(hash_buf), "/" UINTX_FORMAT, (uintx)hash); 2530 hash_len = (int)strlen(hash_buf); 2531 } 2532 2533 // Get the internal name as a c string 2534 const char* src = (const char*) (name()->as_C_string()); 2535 const int src_length = (int)strlen(src); 2536 2537 char* dest = NEW_RESOURCE_ARRAY(char, src_length + hash_len + 3); 2538 2539 // Add L as type indicator 2540 int dest_index = 0; 2541 dest[dest_index++] = 'L'; 2542 2543 // Add the actual class name 2544 for (int src_index = 0; src_index < src_length; ) { 2545 dest[dest_index++] = src[src_index++]; 2546 } 2547 2548 // If we have a hash, append it 2549 for (int hash_index = 0; hash_index < hash_len; ) { 2550 dest[dest_index++] = hash_buf[hash_index++]; 2551 } 2552 2553 // Add the semicolon and the NULL 2554 dest[dest_index++] = ';'; 2555 dest[dest_index] = '\0'; 2556 return dest; 2557 } 2558 2559 // different verisons of is_same_class_package 2560 bool InstanceKlass::is_same_class_package(Klass* class2) { 2561 Klass* class1 = this; 2562 oop classloader1 = InstanceKlass::cast(class1)->class_loader(); 2563 Symbol* classname1 = class1->name(); 2564 2565 if (class2->oop_is_objArray()) { 2566 class2 = ObjArrayKlass::cast(class2)->bottom_klass(); 2567 } 2568 oop classloader2; 2569 if (class2->oop_is_instance()) { 2570 classloader2 = InstanceKlass::cast(class2)->class_loader(); 2571 } else { 2572 assert(class2->oop_is_typeArray(), "should be type array"); 2573 classloader2 = NULL; 2574 } 2575 Symbol* classname2 = class2->name(); 2576 2577 return InstanceKlass::is_same_class_package(classloader1, classname1, 2578 classloader2, classname2); 2579 } 2580 2581 bool InstanceKlass::is_same_class_package(oop classloader2, Symbol* classname2) { 2582 Klass* class1 = this; 2583 oop classloader1 = InstanceKlass::cast(class1)->class_loader(); 2584 Symbol* classname1 = class1->name(); 2585 2586 return InstanceKlass::is_same_class_package(classloader1, classname1, 2587 classloader2, classname2); 2588 } 2589 2590 // return true if two classes are in the same package, classloader 2591 // and classname information is enough to determine a class's package 2592 bool InstanceKlass::is_same_class_package(oop class_loader1, Symbol* class_name1, 2593 oop class_loader2, Symbol* class_name2) { 2594 if (class_loader1 != class_loader2) { 2595 return false; 2596 } else if (class_name1 == class_name2) { 2597 return true; // skip painful bytewise comparison 2598 } else { 2599 ResourceMark rm; 2600 2601 // The Symbol*'s are in UTF8 encoding. Since we only need to check explicitly 2602 // for ASCII characters ('/', 'L', '['), we can keep them in UTF8 encoding. 2603 // Otherwise, we just compare jbyte values between the strings. 2604 const jbyte *name1 = class_name1->base(); 2605 const jbyte *name2 = class_name2->base(); 2606 2607 const jbyte *last_slash1 = UTF8::strrchr(name1, class_name1->utf8_length(), '/'); 2608 const jbyte *last_slash2 = UTF8::strrchr(name2, class_name2->utf8_length(), '/'); 2609 2610 if ((last_slash1 == NULL) || (last_slash2 == NULL)) { 2611 // One of the two doesn't have a package. Only return true 2612 // if the other one also doesn't have a package. 2613 return last_slash1 == last_slash2; 2614 } else { 2615 // Skip over '['s 2616 if (*name1 == '[') { 2617 do { 2618 name1++; 2619 } while (*name1 == '['); 2620 if (*name1 != 'L') { 2621 // Something is terribly wrong. Shouldn't be here. 2622 return false; 2623 } 2624 } 2625 if (*name2 == '[') { 2626 do { 2627 name2++; 2628 } while (*name2 == '['); 2629 if (*name2 != 'L') { 2630 // Something is terribly wrong. Shouldn't be here. 2631 return false; 2632 } 2633 } 2634 2635 // Check that package part is identical 2636 int length1 = last_slash1 - name1; 2637 int length2 = last_slash2 - name2; 2638 2639 return UTF8::equal(name1, length1, name2, length2); 2640 } 2641 } 2642 } 2643 2644 // Returns true iff super_method can be overridden by a method in targetclassname 2645 // See JSL 3rd edition 8.4.6.1 2646 // Assumes name-signature match 2647 // "this" is InstanceKlass of super_method which must exist 2648 // note that the InstanceKlass of the method in the targetclassname has not always been created yet 2649 bool InstanceKlass::is_override(methodHandle super_method, Handle targetclassloader, Symbol* targetclassname, TRAPS) { 2650 // Private methods can not be overridden 2651 if (super_method->is_private()) { 2652 return false; 2653 } 2654 // If super method is accessible, then override 2655 if ((super_method->is_protected()) || 2656 (super_method->is_public())) { 2657 return true; 2658 } 2659 // Package-private methods are not inherited outside of package 2660 assert(super_method->is_package_private(), "must be package private"); 2661 return(is_same_class_package(targetclassloader(), targetclassname)); 2662 } 2663 2664 /* defined for now in jvm.cpp, for historical reasons *-- 2665 Klass* InstanceKlass::compute_enclosing_class_impl(instanceKlassHandle self, 2666 Symbol*& simple_name_result, TRAPS) { 2667 ... 2668 } 2669 */ 2670 2671 // tell if two classes have the same enclosing class (at package level) 2672 bool InstanceKlass::is_same_package_member_impl(instanceKlassHandle class1, 2673 Klass* class2_oop, TRAPS) { 2674 if (class2_oop == class1()) return true; 2675 if (!class2_oop->oop_is_instance()) return false; 2676 instanceKlassHandle class2(THREAD, class2_oop); 2677 2678 // must be in same package before we try anything else 2679 if (!class1->is_same_class_package(class2->class_loader(), class2->name())) 2680 return false; 2681 2682 // As long as there is an outer1.getEnclosingClass, 2683 // shift the search outward. 2684 instanceKlassHandle outer1 = class1; 2685 for (;;) { 2686 // As we walk along, look for equalities between outer1 and class2. 2687 // Eventually, the walks will terminate as outer1 stops 2688 // at the top-level class around the original class. 2689 bool ignore_inner_is_member; 2690 Klass* next = outer1->compute_enclosing_class(&ignore_inner_is_member, 2691 CHECK_false); 2692 if (next == NULL) break; 2693 if (next == class2()) return true; 2694 outer1 = instanceKlassHandle(THREAD, next); 2695 } 2696 2697 // Now do the same for class2. 2698 instanceKlassHandle outer2 = class2; 2699 for (;;) { 2700 bool ignore_inner_is_member; 2701 Klass* next = outer2->compute_enclosing_class(&ignore_inner_is_member, 2702 CHECK_false); 2703 if (next == NULL) break; 2704 // Might as well check the new outer against all available values. 2705 if (next == class1()) return true; 2706 if (next == outer1()) return true; 2707 outer2 = instanceKlassHandle(THREAD, next); 2708 } 2709 2710 // If by this point we have not found an equality between the 2711 // two classes, we know they are in separate package members. 2712 return false; 2713 } 2714 2715 2716 jint InstanceKlass::compute_modifier_flags(TRAPS) const { 2717 jint access = access_flags().as_int(); 2718 2719 // But check if it happens to be member class. 2720 instanceKlassHandle ik(THREAD, this); 2721 InnerClassesIterator iter(ik); 2722 for (; !iter.done(); iter.next()) { 2723 int ioff = iter.inner_class_info_index(); 2724 // Inner class attribute can be zero, skip it. 2725 // Strange but true: JVM spec. allows null inner class refs. 2726 if (ioff == 0) continue; 2727 2728 // only look at classes that are already loaded 2729 // since we are looking for the flags for our self. 2730 Symbol* inner_name = ik->constants()->klass_name_at(ioff); 2731 if ((ik->name() == inner_name)) { 2732 // This is really a member class. 2733 access = iter.inner_access_flags(); 2734 break; 2735 } 2736 } 2737 // Remember to strip ACC_SUPER bit 2738 return (access & (~JVM_ACC_SUPER)) & JVM_ACC_WRITTEN_FLAGS; 2739 } 2740 2741 jint InstanceKlass::jvmti_class_status() const { 2742 jint result = 0; 2743 2744 if (is_linked()) { 2745 result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED; 2746 } 2747 2748 if (is_initialized()) { 2749 assert(is_linked(), "Class status is not consistent"); 2750 result |= JVMTI_CLASS_STATUS_INITIALIZED; 2751 } 2752 if (is_in_error_state()) { 2753 result |= JVMTI_CLASS_STATUS_ERROR; 2754 } 2755 return result; 2756 } 2757 2758 Method* InstanceKlass::method_at_itable(Klass* holder, int index, TRAPS) { 2759 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable(); 2760 int method_table_offset_in_words = ioe->offset()/wordSize; 2761 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words()) 2762 / itableOffsetEntry::size(); 2763 2764 for (int cnt = 0 ; ; cnt ++, ioe ++) { 2765 // If the interface isn't implemented by the receiver class, 2766 // the VM should throw IncompatibleClassChangeError. 2767 if (cnt >= nof_interfaces) { 2768 THROW_NULL(vmSymbols::java_lang_IncompatibleClassChangeError()); 2769 } 2770 2771 Klass* ik = ioe->interface_klass(); 2772 if (ik == holder) break; 2773 } 2774 2775 itableMethodEntry* ime = ioe->first_method_entry(this); 2776 Method* m = ime[index].method(); 2777 if (m == NULL) { 2778 THROW_NULL(vmSymbols::java_lang_AbstractMethodError()); 2779 } 2780 return m; 2781 } 2782 2783 2784 #if INCLUDE_JVMTI 2785 // update default_methods for redefineclasses for methods that are 2786 // not yet in the vtable due to concurrent subclass define and superinterface 2787 // redefinition 2788 // Note: those in the vtable, should have been updated via adjust_method_entries 2789 void InstanceKlass::adjust_default_methods(InstanceKlass* holder, bool* trace_name_printed) { 2790 // search the default_methods for uses of either obsolete or EMCP methods 2791 if (default_methods() != NULL) { 2792 for (int index = 0; index < default_methods()->length(); index ++) { 2793 Method* old_method = default_methods()->at(index); 2794 if (old_method == NULL || old_method->method_holder() != holder || !old_method->is_old()) { 2795 continue; // skip uninteresting entries 2796 } 2797 assert(!old_method->is_deleted(), "default methods may not be deleted"); 2798 2799 Method* new_method = holder->method_with_idnum(old_method->orig_method_idnum()); 2800 2801 assert(new_method != NULL, "method_with_idnum() should not be NULL"); 2802 assert(old_method != new_method, "sanity check"); 2803 2804 default_methods()->at_put(index, new_method); 2805 if (RC_TRACE_IN_RANGE(0x00100000, 0x00400000)) { 2806 if (!(*trace_name_printed)) { 2807 // RC_TRACE_MESG macro has an embedded ResourceMark 2808 RC_TRACE_MESG(("adjust: klassname=%s default methods from name=%s", 2809 external_name(), 2810 old_method->method_holder()->external_name())); 2811 *trace_name_printed = true; 2812 } 2813 RC_TRACE(0x00100000, ("default method update: %s(%s) ", 2814 new_method->name()->as_C_string(), 2815 new_method->signature()->as_C_string())); 2816 } 2817 } 2818 } 2819 } 2820 #endif // INCLUDE_JVMTI 2821 2822 // On-stack replacement stuff 2823 void InstanceKlass::add_osr_nmethod(nmethod* n) { 2824 // only one compilation can be active 2825 { 2826 // This is a short non-blocking critical region, so the no safepoint check is ok. 2827 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag); 2828 assert(n->is_osr_method(), "wrong kind of nmethod"); 2829 n->set_osr_link(osr_nmethods_head()); 2830 set_osr_nmethods_head(n); 2831 // Raise the highest osr level if necessary 2832 if (TieredCompilation) { 2833 Method* m = n->method(); 2834 m->set_highest_osr_comp_level(MAX2(m->highest_osr_comp_level(), n->comp_level())); 2835 } 2836 } 2837 2838 // Get rid of the osr methods for the same bci that have lower levels. 2839 if (TieredCompilation) { 2840 for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) { 2841 nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true); 2842 if (inv != NULL && inv->is_in_use()) { 2843 inv->make_not_entrant(); 2844 } 2845 } 2846 } 2847 } 2848 2849 2850 void InstanceKlass::remove_osr_nmethod(nmethod* n) { 2851 // This is a short non-blocking critical region, so the no safepoint check is ok. 2852 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag); 2853 assert(n->is_osr_method(), "wrong kind of nmethod"); 2854 nmethod* last = NULL; 2855 nmethod* cur = osr_nmethods_head(); 2856 int max_level = CompLevel_none; // Find the max comp level excluding n 2857 Method* m = n->method(); 2858 // Search for match 2859 while(cur != NULL && cur != n) { 2860 if (TieredCompilation && m == cur->method()) { 2861 // Find max level before n 2862 max_level = MAX2(max_level, cur->comp_level()); 2863 } 2864 last = cur; 2865 cur = cur->osr_link(); 2866 } 2867 nmethod* next = NULL; 2868 if (cur == n) { 2869 next = cur->osr_link(); 2870 if (last == NULL) { 2871 // Remove first element 2872 set_osr_nmethods_head(next); 2873 } else { 2874 last->set_osr_link(next); 2875 } 2876 } 2877 n->set_osr_link(NULL); 2878 if (TieredCompilation) { 2879 cur = next; 2880 while (cur != NULL) { 2881 // Find max level after n 2882 if (m == cur->method()) { 2883 max_level = MAX2(max_level, cur->comp_level()); 2884 } 2885 cur = cur->osr_link(); 2886 } 2887 m->set_highest_osr_comp_level(max_level); 2888 } 2889 } 2890 2891 int InstanceKlass::mark_osr_nmethods(const Method* m) { 2892 // This is a short non-blocking critical region, so the no safepoint check is ok. 2893 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag); 2894 nmethod* osr = osr_nmethods_head(); 2895 int found = 0; 2896 while (osr != NULL) { 2897 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain"); 2898 if (osr->method() == m) { 2899 osr->mark_for_deoptimization(); 2900 found++; 2901 } 2902 osr = osr->osr_link(); 2903 } 2904 return found; 2905 } 2906 2907 nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const { 2908 // This is a short non-blocking critical region, so the no safepoint check is ok. 2909 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag); 2910 nmethod* osr = osr_nmethods_head(); 2911 nmethod* best = NULL; 2912 while (osr != NULL) { 2913 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain"); 2914 // There can be a time when a c1 osr method exists but we are waiting 2915 // for a c2 version. When c2 completes its osr nmethod we will trash 2916 // the c1 version and only be able to find the c2 version. However 2917 // while we overflow in the c1 code at back branches we don't want to 2918 // try and switch to the same code as we are already running 2919 2920 if (osr->method() == m && 2921 (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) { 2922 if (match_level) { 2923 if (osr->comp_level() == comp_level) { 2924 // Found a match - return it. 2925 return osr; 2926 } 2927 } else { 2928 if (best == NULL || (osr->comp_level() > best->comp_level())) { 2929 if (osr->comp_level() == CompLevel_highest_tier) { 2930 // Found the best possible - return it. 2931 return osr; 2932 } 2933 best = osr; 2934 } 2935 } 2936 } 2937 osr = osr->osr_link(); 2938 } 2939 if (best != NULL && best->comp_level() >= comp_level && match_level == false) { 2940 return best; 2941 } 2942 return NULL; 2943 } 2944 2945 bool InstanceKlass::add_member_name(Handle mem_name) { 2946 jweak mem_name_wref = JNIHandles::make_weak_global(mem_name); 2947 MutexLocker ml(MemberNameTable_lock); 2948 DEBUG_ONLY(No_Safepoint_Verifier nsv); 2949 2950 // Check if method has been redefined while taking out MemberNameTable_lock, if so 2951 // return false. We cannot cache obsolete methods. They will crash when the function 2952 // is called! 2953 Method* method = (Method*)java_lang_invoke_MemberName::vmtarget(mem_name()); 2954 if (method->is_obsolete()) { 2955 return false; 2956 } else if (method->is_old()) { 2957 // Replace method with redefined version 2958 java_lang_invoke_MemberName::set_vmtarget(mem_name(), method_with_idnum(method->method_idnum())); 2959 } 2960 2961 if (_member_names == NULL) { 2962 _member_names = new (ResourceObj::C_HEAP, mtClass) MemberNameTable(idnum_allocated_count()); 2963 } 2964 _member_names->add_member_name(mem_name_wref); 2965 return true; 2966 } 2967 2968 // ----------------------------------------------------------------------------------------------------- 2969 // Printing 2970 2971 #ifndef PRODUCT 2972 2973 #define BULLET " - " 2974 2975 static const char* state_names[] = { 2976 "allocated", "loaded", "linked", "being_initialized", "fully_initialized", "initialization_error" 2977 }; 2978 2979 static void print_vtable(intptr_t* start, int len, outputStream* st) { 2980 for (int i = 0; i < len; i++) { 2981 intptr_t e = start[i]; 2982 st->print("%d : " INTPTR_FORMAT, i, e); 2983 if (e != 0 && ((Metadata*)e)->is_metaspace_object()) { 2984 st->print(" "); 2985 ((Metadata*)e)->print_value_on(st); 2986 } 2987 st->cr(); 2988 } 2989 } 2990 2991 void InstanceKlass::print_on(outputStream* st) const { 2992 assert(is_klass(), "must be klass"); 2993 Klass::print_on(st); 2994 2995 st->print(BULLET"instance size: %d", size_helper()); st->cr(); 2996 st->print(BULLET"klass size: %d", size()); st->cr(); 2997 st->print(BULLET"access: "); access_flags().print_on(st); st->cr(); 2998 st->print(BULLET"state: "); st->print_cr("%s", state_names[_init_state]); 2999 st->print(BULLET"name: "); name()->print_value_on(st); st->cr(); 3000 st->print(BULLET"super: "); super()->print_value_on_maybe_null(st); st->cr(); 3001 st->print(BULLET"sub: "); 3002 Klass* sub = subklass(); 3003 int n; 3004 for (n = 0; sub != NULL; n++, sub = sub->next_sibling()) { 3005 if (n < MaxSubklassPrintSize) { 3006 sub->print_value_on(st); 3007 st->print(" "); 3008 } 3009 } 3010 if (n >= MaxSubklassPrintSize) st->print("(%d more klasses...)", n - MaxSubklassPrintSize); 3011 st->cr(); 3012 3013 if (is_interface()) { 3014 st->print_cr(BULLET"nof implementors: %d", nof_implementors()); 3015 if (nof_implementors() == 1) { 3016 st->print_cr(BULLET"implementor: "); 3017 st->print(" "); 3018 implementor()->print_value_on(st); 3019 st->cr(); 3020 } 3021 } 3022 3023 st->print(BULLET"arrays: "); array_klasses()->print_value_on_maybe_null(st); st->cr(); 3024 st->print(BULLET"methods: "); methods()->print_value_on(st); st->cr(); 3025 if (Verbose || WizardMode) { 3026 Array<Method*>* method_array = methods(); 3027 for (int i = 0; i < method_array->length(); i++) { 3028 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr(); 3029 } 3030 } 3031 st->print(BULLET"method ordering: "); method_ordering()->print_value_on(st); st->cr(); 3032 st->print(BULLET"default_methods: "); default_methods()->print_value_on(st); st->cr(); 3033 if (Verbose && default_methods() != NULL) { 3034 Array<Method*>* method_array = default_methods(); 3035 for (int i = 0; i < method_array->length(); i++) { 3036 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr(); 3037 } 3038 } 3039 if (default_vtable_indices() != NULL) { 3040 st->print(BULLET"default vtable indices: "); default_vtable_indices()->print_value_on(st); st->cr(); 3041 } 3042 st->print(BULLET"local interfaces: "); local_interfaces()->print_value_on(st); st->cr(); 3043 st->print(BULLET"trans. interfaces: "); transitive_interfaces()->print_value_on(st); st->cr(); 3044 st->print(BULLET"constants: "); constants()->print_value_on(st); st->cr(); 3045 if (class_loader_data() != NULL) { 3046 st->print(BULLET"class loader data: "); 3047 class_loader_data()->print_value_on(st); 3048 st->cr(); 3049 } 3050 st->print(BULLET"host class: "); host_klass()->print_value_on_maybe_null(st); st->cr(); 3051 if (source_file_name() != NULL) { 3052 st->print(BULLET"source file: "); 3053 source_file_name()->print_value_on(st); 3054 st->cr(); 3055 } 3056 if (source_debug_extension() != NULL) { 3057 st->print(BULLET"source debug extension: "); 3058 st->print("%s", source_debug_extension()); 3059 st->cr(); 3060 } 3061 st->print(BULLET"class annotations: "); class_annotations()->print_value_on(st); st->cr(); 3062 st->print(BULLET"class type annotations: "); class_type_annotations()->print_value_on(st); st->cr(); 3063 st->print(BULLET"field annotations: "); fields_annotations()->print_value_on(st); st->cr(); 3064 st->print(BULLET"field type annotations: "); fields_type_annotations()->print_value_on(st); st->cr(); 3065 { 3066 bool have_pv = false; 3067 // previous versions are linked together through the InstanceKlass 3068 for (InstanceKlass* pv_node = _previous_versions; 3069 pv_node != NULL; 3070 pv_node = pv_node->previous_versions()) { 3071 if (!have_pv) 3072 st->print(BULLET"previous version: "); 3073 have_pv = true; 3074 pv_node->constants()->print_value_on(st); 3075 } 3076 if (have_pv) st->cr(); 3077 } 3078 3079 if (generic_signature() != NULL) { 3080 st->print(BULLET"generic signature: "); 3081 generic_signature()->print_value_on(st); 3082 st->cr(); 3083 } 3084 st->print(BULLET"inner classes: "); inner_classes()->print_value_on(st); st->cr(); 3085 st->print(BULLET"java mirror: "); java_mirror()->print_value_on(st); st->cr(); 3086 st->print(BULLET"vtable length %d (start addr: " INTPTR_FORMAT ")", vtable_length(), start_of_vtable()); st->cr(); 3087 if (vtable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_vtable(), vtable_length(), st); 3088 st->print(BULLET"itable length %d (start addr: " INTPTR_FORMAT ")", itable_length(), start_of_itable()); st->cr(); 3089 if (itable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_itable(), itable_length(), st); 3090 st->print_cr(BULLET"---- static fields (%d words):", static_field_size()); 3091 FieldPrinter print_static_field(st); 3092 ((InstanceKlass*)this)->do_local_static_fields(&print_static_field); 3093 st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size()); 3094 FieldPrinter print_nonstatic_field(st); 3095 ((InstanceKlass*)this)->do_nonstatic_fields(&print_nonstatic_field); 3096 3097 st->print(BULLET"non-static oop maps: "); 3098 OopMapBlock* map = start_of_nonstatic_oop_maps(); 3099 OopMapBlock* end_map = map + nonstatic_oop_map_count(); 3100 while (map < end_map) { 3101 st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1)); 3102 map++; 3103 } 3104 st->cr(); 3105 } 3106 3107 #endif //PRODUCT 3108 3109 void InstanceKlass::print_value_on(outputStream* st) const { 3110 assert(is_klass(), "must be klass"); 3111 if (Verbose || WizardMode) access_flags().print_on(st); 3112 name()->print_value_on(st); 3113 } 3114 3115 #ifndef PRODUCT 3116 3117 void FieldPrinter::do_field(fieldDescriptor* fd) { 3118 _st->print(BULLET); 3119 if (_obj == NULL) { 3120 fd->print_on(_st); 3121 _st->cr(); 3122 } else { 3123 fd->print_on_for(_st, _obj); 3124 _st->cr(); 3125 } 3126 } 3127 3128 3129 void InstanceKlass::oop_print_on(oop obj, outputStream* st) { 3130 Klass::oop_print_on(obj, st); 3131 3132 if (this == SystemDictionary::String_klass()) { 3133 typeArrayOop value = java_lang_String::value(obj); 3134 juint offset = java_lang_String::offset(obj); 3135 juint length = java_lang_String::length(obj); 3136 if (value != NULL && 3137 value->is_typeArray() && 3138 offset <= (juint) value->length() && 3139 offset + length <= (juint) value->length()) { 3140 st->print(BULLET"string: "); 3141 java_lang_String::print(obj, st); 3142 st->cr(); 3143 if (!WizardMode) return; // that is enough 3144 } 3145 } 3146 3147 st->print_cr(BULLET"---- fields (total size %d words):", oop_size(obj)); 3148 FieldPrinter print_field(st, obj); 3149 do_nonstatic_fields(&print_field); 3150 3151 if (this == SystemDictionary::Class_klass()) { 3152 st->print(BULLET"signature: "); 3153 java_lang_Class::print_signature(obj, st); 3154 st->cr(); 3155 Klass* mirrored_klass = java_lang_Class::as_Klass(obj); 3156 st->print(BULLET"fake entry for mirror: "); 3157 mirrored_klass->print_value_on_maybe_null(st); 3158 st->cr(); 3159 Klass* array_klass = java_lang_Class::array_klass(obj); 3160 st->print(BULLET"fake entry for array: "); 3161 array_klass->print_value_on_maybe_null(st); 3162 st->cr(); 3163 st->print_cr(BULLET"fake entry for oop_size: %d", java_lang_Class::oop_size(obj)); 3164 st->print_cr(BULLET"fake entry for static_oop_field_count: %d", java_lang_Class::static_oop_field_count(obj)); 3165 Klass* real_klass = java_lang_Class::as_Klass(obj); 3166 if (real_klass != NULL && real_klass->oop_is_instance()) { 3167 InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field); 3168 } 3169 } else if (this == SystemDictionary::MethodType_klass()) { 3170 st->print(BULLET"signature: "); 3171 java_lang_invoke_MethodType::print_signature(obj, st); 3172 st->cr(); 3173 } 3174 } 3175 3176 #endif //PRODUCT 3177 3178 void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) { 3179 st->print("a "); 3180 name()->print_value_on(st); 3181 obj->print_address_on(st); 3182 if (this == SystemDictionary::String_klass() 3183 && java_lang_String::value(obj) != NULL) { 3184 ResourceMark rm; 3185 int len = java_lang_String::length(obj); 3186 int plen = (len < 24 ? len : 12); 3187 char* str = java_lang_String::as_utf8_string(obj, 0, plen); 3188 st->print(" = \"%s\"", str); 3189 if (len > plen) 3190 st->print("...[%d]", len); 3191 } else if (this == SystemDictionary::Class_klass()) { 3192 Klass* k = java_lang_Class::as_Klass(obj); 3193 st->print(" = "); 3194 if (k != NULL) { 3195 k->print_value_on(st); 3196 } else { 3197 const char* tname = type2name(java_lang_Class::primitive_type(obj)); 3198 st->print("%s", tname ? tname : "type?"); 3199 } 3200 } else if (this == SystemDictionary::MethodType_klass()) { 3201 st->print(" = "); 3202 java_lang_invoke_MethodType::print_signature(obj, st); 3203 } else if (java_lang_boxing_object::is_instance(obj)) { 3204 st->print(" = "); 3205 java_lang_boxing_object::print(obj, st); 3206 } else if (this == SystemDictionary::LambdaForm_klass()) { 3207 oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj); 3208 if (vmentry != NULL) { 3209 st->print(" => "); 3210 vmentry->print_value_on(st); 3211 } 3212 } else if (this == SystemDictionary::MemberName_klass()) { 3213 Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj); 3214 if (vmtarget != NULL) { 3215 st->print(" = "); 3216 vmtarget->print_value_on(st); 3217 } else { 3218 java_lang_invoke_MemberName::clazz(obj)->print_value_on(st); 3219 st->print("."); 3220 java_lang_invoke_MemberName::name(obj)->print_value_on(st); 3221 } 3222 } 3223 } 3224 3225 const char* InstanceKlass::internal_name() const { 3226 return external_name(); 3227 } 3228 3229 #if INCLUDE_SERVICES 3230 // Size Statistics 3231 void InstanceKlass::collect_statistics(KlassSizeStats *sz) const { 3232 Klass::collect_statistics(sz); 3233 3234 sz->_inst_size = HeapWordSize * size_helper(); 3235 sz->_vtab_bytes = HeapWordSize * align_object_offset(vtable_length()); 3236 sz->_itab_bytes = HeapWordSize * align_object_offset(itable_length()); 3237 sz->_nonstatic_oopmap_bytes = HeapWordSize * 3238 ((is_interface() || is_anonymous()) ? 3239 align_object_offset(nonstatic_oop_map_size()) : 3240 nonstatic_oop_map_size()); 3241 3242 int n = 0; 3243 n += (sz->_methods_array_bytes = sz->count_array(methods())); 3244 n += (sz->_method_ordering_bytes = sz->count_array(method_ordering())); 3245 n += (sz->_local_interfaces_bytes = sz->count_array(local_interfaces())); 3246 n += (sz->_transitive_interfaces_bytes = sz->count_array(transitive_interfaces())); 3247 n += (sz->_fields_bytes = sz->count_array(fields())); 3248 n += (sz->_inner_classes_bytes = sz->count_array(inner_classes())); 3249 sz->_ro_bytes += n; 3250 3251 const ConstantPool* cp = constants(); 3252 if (cp) { 3253 cp->collect_statistics(sz); 3254 } 3255 3256 const Annotations* anno = annotations(); 3257 if (anno) { 3258 anno->collect_statistics(sz); 3259 } 3260 3261 const Array<Method*>* methods_array = methods(); 3262 if (methods()) { 3263 for (int i = 0; i < methods_array->length(); i++) { 3264 Method* method = methods_array->at(i); 3265 if (method) { 3266 sz->_method_count ++; 3267 method->collect_statistics(sz); 3268 } 3269 } 3270 } 3271 } 3272 #endif // INCLUDE_SERVICES 3273 3274 // Verification 3275 3276 class VerifyFieldClosure: public OopClosure { 3277 protected: 3278 template <class T> void do_oop_work(T* p) { 3279 oop obj = oopDesc::load_decode_heap_oop(p); 3280 if (!obj->is_oop_or_null()) { 3281 tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p, (address)obj); 3282 Universe::print(); 3283 guarantee(false, "boom"); 3284 } 3285 } 3286 public: 3287 virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); } 3288 virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); } 3289 }; 3290 3291 void InstanceKlass::verify_on(outputStream* st) { 3292 #ifndef PRODUCT 3293 // Avoid redundant verifies, this really should be in product. 3294 if (_verify_count == Universe::verify_count()) return; 3295 _verify_count = Universe::verify_count(); 3296 #endif 3297 3298 // Verify Klass 3299 Klass::verify_on(st); 3300 3301 // Verify that klass is present in ClassLoaderData 3302 guarantee(class_loader_data()->contains_klass(this), 3303 "this class isn't found in class loader data"); 3304 3305 // Verify vtables 3306 if (is_linked()) { 3307 ResourceMark rm; 3308 // $$$ This used to be done only for m/s collections. Doing it 3309 // always seemed a valid generalization. (DLD -- 6/00) 3310 vtable()->verify(st); 3311 } 3312 3313 // Verify first subklass 3314 if (subklass() != NULL) { 3315 guarantee(subklass()->is_klass(), "should be klass"); 3316 } 3317 3318 // Verify siblings 3319 Klass* super = this->super(); 3320 Klass* sib = next_sibling(); 3321 if (sib != NULL) { 3322 if (sib == this) { 3323 fatal(err_msg("subclass points to itself " PTR_FORMAT, sib)); 3324 } 3325 3326 guarantee(sib->is_klass(), "should be klass"); 3327 guarantee(sib->super() == super, "siblings should have same superklass"); 3328 } 3329 3330 // Verify implementor fields 3331 Klass* im = implementor(); 3332 if (im != NULL) { 3333 guarantee(is_interface(), "only interfaces should have implementor set"); 3334 guarantee(im->is_klass(), "should be klass"); 3335 guarantee(!im->is_interface() || im == this, 3336 "implementors cannot be interfaces"); 3337 } 3338 3339 // Verify local interfaces 3340 if (local_interfaces()) { 3341 Array<Klass*>* local_interfaces = this->local_interfaces(); 3342 for (int j = 0; j < local_interfaces->length(); j++) { 3343 Klass* e = local_interfaces->at(j); 3344 guarantee(e->is_klass() && e->is_interface(), "invalid local interface"); 3345 } 3346 } 3347 3348 // Verify transitive interfaces 3349 if (transitive_interfaces() != NULL) { 3350 Array<Klass*>* transitive_interfaces = this->transitive_interfaces(); 3351 for (int j = 0; j < transitive_interfaces->length(); j++) { 3352 Klass* e = transitive_interfaces->at(j); 3353 guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface"); 3354 } 3355 } 3356 3357 // Verify methods 3358 if (methods() != NULL) { 3359 Array<Method*>* methods = this->methods(); 3360 for (int j = 0; j < methods->length(); j++) { 3361 guarantee(methods->at(j)->is_method(), "non-method in methods array"); 3362 } 3363 for (int j = 0; j < methods->length() - 1; j++) { 3364 Method* m1 = methods->at(j); 3365 Method* m2 = methods->at(j + 1); 3366 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly"); 3367 } 3368 } 3369 3370 // Verify method ordering 3371 if (method_ordering() != NULL) { 3372 Array<int>* method_ordering = this->method_ordering(); 3373 int length = method_ordering->length(); 3374 if (JvmtiExport::can_maintain_original_method_order() || 3375 ((UseSharedSpaces || DumpSharedSpaces) && length != 0)) { 3376 guarantee(length == methods()->length(), "invalid method ordering length"); 3377 jlong sum = 0; 3378 for (int j = 0; j < length; j++) { 3379 int original_index = method_ordering->at(j); 3380 guarantee(original_index >= 0, "invalid method ordering index"); 3381 guarantee(original_index < length, "invalid method ordering index"); 3382 sum += original_index; 3383 } 3384 // Verify sum of indices 0,1,...,length-1 3385 guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum"); 3386 } else { 3387 guarantee(length == 0, "invalid method ordering length"); 3388 } 3389 } 3390 3391 // Verify default methods 3392 if (default_methods() != NULL) { 3393 Array<Method*>* methods = this->default_methods(); 3394 for (int j = 0; j < methods->length(); j++) { 3395 guarantee(methods->at(j)->is_method(), "non-method in methods array"); 3396 } 3397 for (int j = 0; j < methods->length() - 1; j++) { 3398 Method* m1 = methods->at(j); 3399 Method* m2 = methods->at(j + 1); 3400 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly"); 3401 } 3402 } 3403 3404 // Verify JNI static field identifiers 3405 if (jni_ids() != NULL) { 3406 jni_ids()->verify(this); 3407 } 3408 3409 // Verify other fields 3410 if (array_klasses() != NULL) { 3411 guarantee(array_klasses()->is_klass(), "should be klass"); 3412 } 3413 if (constants() != NULL) { 3414 guarantee(constants()->is_constantPool(), "should be constant pool"); 3415 } 3416 const Klass* host = host_klass(); 3417 if (host != NULL) { 3418 guarantee(host->is_klass(), "should be klass"); 3419 } 3420 } 3421 3422 void InstanceKlass::oop_verify_on(oop obj, outputStream* st) { 3423 Klass::oop_verify_on(obj, st); 3424 VerifyFieldClosure blk; 3425 obj->oop_iterate_no_header(&blk); 3426 } 3427 3428 3429 // JNIid class for jfieldIDs only 3430 // Note to reviewers: 3431 // These JNI functions are just moved over to column 1 and not changed 3432 // in the compressed oops workspace. 3433 JNIid::JNIid(Klass* holder, int offset, JNIid* next) { 3434 _holder = holder; 3435 _offset = offset; 3436 _next = next; 3437 debug_only(_is_static_field_id = false;) 3438 } 3439 3440 3441 JNIid* JNIid::find(int offset) { 3442 JNIid* current = this; 3443 while (current != NULL) { 3444 if (current->offset() == offset) return current; 3445 current = current->next(); 3446 } 3447 return NULL; 3448 } 3449 3450 void JNIid::deallocate(JNIid* current) { 3451 while (current != NULL) { 3452 JNIid* next = current->next(); 3453 delete current; 3454 current = next; 3455 } 3456 } 3457 3458 3459 void JNIid::verify(Klass* holder) { 3460 int first_field_offset = InstanceMirrorKlass::offset_of_static_fields(); 3461 int end_field_offset; 3462 end_field_offset = first_field_offset + (InstanceKlass::cast(holder)->static_field_size() * wordSize); 3463 3464 JNIid* current = this; 3465 while (current != NULL) { 3466 guarantee(current->holder() == holder, "Invalid klass in JNIid"); 3467 #ifdef ASSERT 3468 int o = current->offset(); 3469 if (current->is_static_field_id()) { 3470 guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid"); 3471 } 3472 #endif 3473 current = current->next(); 3474 } 3475 } 3476 3477 3478 #ifdef ASSERT 3479 void InstanceKlass::set_init_state(ClassState state) { 3480 bool good_state = is_shared() ? (_init_state <= state) 3481 : (_init_state < state); 3482 assert(good_state || state == allocated, "illegal state transition"); 3483 _init_state = (u1)state; 3484 } 3485 #endif 3486 3487 3488 3489 // RedefineClasses() support for previous versions: 3490 int InstanceKlass::_previous_version_count = 0; 3491 3492 // Purge previous versions before adding new previous versions of the class. 3493 void InstanceKlass::purge_previous_versions(InstanceKlass* ik) { 3494 if (ik->previous_versions() != NULL) { 3495 // This klass has previous versions so see what we can cleanup 3496 // while it is safe to do so. 3497 3498 int deleted_count = 0; // leave debugging breadcrumbs 3499 int live_count = 0; 3500 ClassLoaderData* loader_data = ik->class_loader_data(); 3501 assert(loader_data != NULL, "should never be null"); 3502 3503 // RC_TRACE macro has an embedded ResourceMark 3504 RC_TRACE(0x00000200, ("purge: %s: previous versions", ik->external_name())); 3505 3506 // previous versions are linked together through the InstanceKlass 3507 InstanceKlass* pv_node = ik->previous_versions(); 3508 InstanceKlass* last = ik; 3509 int version = 0; 3510 3511 // check the previous versions list 3512 for (; pv_node != NULL; ) { 3513 3514 ConstantPool* pvcp = pv_node->constants(); 3515 assert(pvcp != NULL, "cp ref was unexpectedly cleared"); 3516 3517 if (!pvcp->on_stack()) { 3518 // If the constant pool isn't on stack, none of the methods 3519 // are executing. Unlink this previous_version. 3520 // The previous version InstanceKlass is on the ClassLoaderData deallocate list 3521 // so will be deallocated during the next phase of class unloading. 3522 RC_TRACE(0x00000200, ("purge: previous version " INTPTR_FORMAT " is dead", 3523 pv_node)); 3524 // For debugging purposes. 3525 pv_node->set_is_scratch_class(); 3526 pv_node->class_loader_data()->add_to_deallocate_list(pv_node); 3527 pv_node = pv_node->previous_versions(); 3528 last->link_previous_versions(pv_node); 3529 deleted_count++; 3530 version++; 3531 continue; 3532 } else { 3533 RC_TRACE(0x00000200, ("purge: previous version " INTPTR_FORMAT " is alive", 3534 pv_node)); 3535 assert(pvcp->pool_holder() != NULL, "Constant pool with no holder"); 3536 guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack"); 3537 live_count++; 3538 } 3539 3540 // At least one method is live in this previous version. 3541 // Reset dead EMCP methods not to get breakpoints. 3542 // All methods are deallocated when all of the methods for this class are no 3543 // longer running. 3544 Array<Method*>* method_refs = pv_node->methods(); 3545 if (method_refs != NULL) { 3546 RC_TRACE(0x00000200, ("purge: previous methods length=%d", 3547 method_refs->length())); 3548 for (int j = 0; j < method_refs->length(); j++) { 3549 Method* method = method_refs->at(j); 3550 3551 if (!method->on_stack()) { 3552 // no breakpoints for non-running methods 3553 if (method->is_running_emcp()) { 3554 method->set_running_emcp(false); 3555 } 3556 } else { 3557 assert (method->is_obsolete() || method->is_running_emcp(), 3558 "emcp method cannot run after emcp bit is cleared"); 3559 // RC_TRACE macro has an embedded ResourceMark 3560 RC_TRACE(0x00000200, 3561 ("purge: %s(%s): prev method @%d in version @%d is alive", 3562 method->name()->as_C_string(), 3563 method->signature()->as_C_string(), j, version)); 3564 } 3565 } 3566 } 3567 // next previous version 3568 last = pv_node; 3569 pv_node = pv_node->previous_versions(); 3570 version++; 3571 } 3572 RC_TRACE(0x00000200, 3573 ("purge: previous version stats: live=%d, deleted=%d", live_count, 3574 deleted_count)); 3575 } 3576 } 3577 3578 void InstanceKlass::mark_newly_obsolete_methods(Array<Method*>* old_methods, 3579 int emcp_method_count) { 3580 int obsolete_method_count = old_methods->length() - emcp_method_count; 3581 3582 if (emcp_method_count != 0 && obsolete_method_count != 0 && 3583 _previous_versions != NULL) { 3584 // We have a mix of obsolete and EMCP methods so we have to 3585 // clear out any matching EMCP method entries the hard way. 3586 int local_count = 0; 3587 for (int i = 0; i < old_methods->length(); i++) { 3588 Method* old_method = old_methods->at(i); 3589 if (old_method->is_obsolete()) { 3590 // only obsolete methods are interesting 3591 Symbol* m_name = old_method->name(); 3592 Symbol* m_signature = old_method->signature(); 3593 3594 // previous versions are linked together through the InstanceKlass 3595 int j = 0; 3596 for (InstanceKlass* prev_version = _previous_versions; 3597 prev_version != NULL; 3598 prev_version = prev_version->previous_versions(), j++) { 3599 3600 Array<Method*>* method_refs = prev_version->methods(); 3601 for (int k = 0; k < method_refs->length(); k++) { 3602 Method* method = method_refs->at(k); 3603 3604 if (!method->is_obsolete() && 3605 method->name() == m_name && 3606 method->signature() == m_signature) { 3607 // The current RedefineClasses() call has made all EMCP 3608 // versions of this method obsolete so mark it as obsolete 3609 RC_TRACE(0x00000400, 3610 ("add: %s(%s): flush obsolete method @%d in version @%d", 3611 m_name->as_C_string(), m_signature->as_C_string(), k, j)); 3612 3613 method->set_is_obsolete(); 3614 break; 3615 } 3616 } 3617 3618 // The previous loop may not find a matching EMCP method, but 3619 // that doesn't mean that we can optimize and not go any 3620 // further back in the PreviousVersion generations. The EMCP 3621 // method for this generation could have already been made obsolete, 3622 // but there still may be an older EMCP method that has not 3623 // been made obsolete. 3624 } 3625 3626 if (++local_count >= obsolete_method_count) { 3627 // no more obsolete methods so bail out now 3628 break; 3629 } 3630 } 3631 } 3632 } 3633 } 3634 3635 // Save the scratch_class as the previous version if any of the methods are running. 3636 // The previous_versions are used to set breakpoints in EMCP methods and they are 3637 // also used to clean MethodData links to redefined methods that are no longer running. 3638 void InstanceKlass::add_previous_version(instanceKlassHandle scratch_class, 3639 int emcp_method_count) { 3640 assert(Thread::current()->is_VM_thread(), 3641 "only VMThread can add previous versions"); 3642 3643 // RC_TRACE macro has an embedded ResourceMark 3644 RC_TRACE(0x00000400, ("adding previous version ref for %s, EMCP_cnt=%d", 3645 scratch_class->external_name(), emcp_method_count)); 3646 3647 // Clean out old previous versions 3648 purge_previous_versions(this); 3649 3650 // Mark newly obsolete methods in remaining previous versions. An EMCP method from 3651 // a previous redefinition may be made obsolete by this redefinition. 3652 Array<Method*>* old_methods = scratch_class->methods(); 3653 mark_newly_obsolete_methods(old_methods, emcp_method_count); 3654 3655 // If the constant pool for this previous version of the class 3656 // is not marked as being on the stack, then none of the methods 3657 // in this previous version of the class are on the stack so 3658 // we don't need to add this as a previous version. 3659 ConstantPool* cp_ref = scratch_class->constants(); 3660 if (!cp_ref->on_stack()) { 3661 RC_TRACE(0x00000400, ("add: scratch class not added; no methods are running")); 3662 // For debugging purposes. 3663 scratch_class->set_is_scratch_class(); 3664 scratch_class->class_loader_data()->add_to_deallocate_list(scratch_class()); 3665 // Update count for class unloading. 3666 _previous_version_count--; 3667 return; 3668 } 3669 3670 if (emcp_method_count != 0) { 3671 // At least one method is still running, check for EMCP methods 3672 for (int i = 0; i < old_methods->length(); i++) { 3673 Method* old_method = old_methods->at(i); 3674 if (!old_method->is_obsolete() && old_method->on_stack()) { 3675 // if EMCP method (not obsolete) is on the stack, mark as EMCP so that 3676 // we can add breakpoints for it. 3677 3678 // We set the method->on_stack bit during safepoints for class redefinition 3679 // and use this bit to set the is_running_emcp bit. 3680 // After the safepoint, the on_stack bit is cleared and the running emcp 3681 // method may exit. If so, we would set a breakpoint in a method that 3682 // is never reached, but this won't be noticeable to the programmer. 3683 old_method->set_running_emcp(true); 3684 RC_TRACE(0x00000400, ("add: EMCP method %s is on_stack " INTPTR_FORMAT, 3685 old_method->name_and_sig_as_C_string(), old_method)); 3686 } else if (!old_method->is_obsolete()) { 3687 RC_TRACE(0x00000400, ("add: EMCP method %s is NOT on_stack " INTPTR_FORMAT, 3688 old_method->name_and_sig_as_C_string(), old_method)); 3689 } 3690 } 3691 } 3692 3693 // Add previous version if any methods are still running. 3694 RC_TRACE(0x00000400, ("add: scratch class added; one of its methods is on_stack")); 3695 assert(scratch_class->previous_versions() == NULL, "shouldn't have a previous version"); 3696 scratch_class->link_previous_versions(previous_versions()); 3697 link_previous_versions(scratch_class()); 3698 // Update count for class unloading. 3699 _previous_version_count++; 3700 } // end add_previous_version() 3701 3702 3703 Method* InstanceKlass::method_with_idnum(int idnum) { 3704 Method* m = NULL; 3705 if (idnum < methods()->length()) { 3706 m = methods()->at(idnum); 3707 } 3708 if (m == NULL || m->method_idnum() != idnum) { 3709 for (int index = 0; index < methods()->length(); ++index) { 3710 m = methods()->at(index); 3711 if (m->method_idnum() == idnum) { 3712 return m; 3713 } 3714 } 3715 // None found, return null for the caller to handle. 3716 return NULL; 3717 } 3718 return m; 3719 } 3720 3721 jint InstanceKlass::get_cached_class_file_len() { 3722 return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file); 3723 } 3724 3725 unsigned char * InstanceKlass::get_cached_class_file_bytes() { 3726 return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file); 3727 }