1 /* 2 * Copyright (c) 1997, 2018, 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 "jvm.h" 27 #include "aot/aotLoader.hpp" 28 #include "classfile/classFileParser.hpp" 29 #include "classfile/classFileStream.hpp" 30 #include "classfile/classLoader.hpp" 31 #include "classfile/classLoaderData.inline.hpp" 32 #include "classfile/javaClasses.hpp" 33 #include "classfile/moduleEntry.hpp" 34 #include "classfile/systemDictionary.hpp" 35 #include "classfile/systemDictionaryShared.hpp" 36 #include "classfile/verifier.hpp" 37 #include "classfile/vmSymbols.hpp" 38 #include "code/dependencyContext.hpp" 39 #include "compiler/compileBroker.hpp" 40 #include "gc/shared/collectedHeap.inline.hpp" 41 #include "gc/shared/specialized_oop_closures.hpp" 42 #include "interpreter/oopMapCache.hpp" 43 #include "interpreter/rewriter.hpp" 44 #include "jvmtifiles/jvmti.h" 45 #include "logging/log.hpp" 46 #include "logging/logMessage.hpp" 47 #include "logging/logStream.hpp" 48 #include "memory/allocation.inline.hpp" 49 #include "memory/heapInspection.hpp" 50 #include "memory/iterator.inline.hpp" 51 #include "memory/metadataFactory.hpp" 52 #include "memory/metaspaceClosure.hpp" 53 #include "memory/metaspaceShared.hpp" 54 #include "memory/oopFactory.hpp" 55 #include "memory/resourceArea.hpp" 56 #include "oops/fieldStreams.hpp" 57 #include "oops/instanceClassLoaderKlass.hpp" 58 #include "oops/instanceKlass.inline.hpp" 59 #include "oops/instanceMirrorKlass.hpp" 60 #include "oops/instanceOop.hpp" 61 #include "oops/klass.inline.hpp" 62 #include "oops/method.hpp" 63 #include "oops/oop.inline.hpp" 64 #include "oops/symbol.hpp" 65 #include "prims/jvmtiExport.hpp" 66 #include "prims/jvmtiRedefineClasses.hpp" 67 #include "prims/jvmtiThreadState.hpp" 68 #include "prims/methodComparator.hpp" 69 #include "runtime/atomic.hpp" 70 #include "runtime/fieldDescriptor.hpp" 71 #include "runtime/handles.inline.hpp" 72 #include "runtime/javaCalls.hpp" 73 #include "runtime/mutexLocker.hpp" 74 #include "runtime/orderAccess.hpp" 75 #include "runtime/thread.inline.hpp" 76 #include "services/classLoadingService.hpp" 77 #include "services/threadService.hpp" 78 #include "utilities/dtrace.hpp" 79 #include "utilities/macros.hpp" 80 #include "utilities/stringUtils.hpp" 81 #ifdef COMPILER1 82 #include "c1/c1_Compiler.hpp" 83 #endif 84 85 #ifdef DTRACE_ENABLED 86 87 88 #define HOTSPOT_CLASS_INITIALIZATION_required HOTSPOT_CLASS_INITIALIZATION_REQUIRED 89 #define HOTSPOT_CLASS_INITIALIZATION_recursive HOTSPOT_CLASS_INITIALIZATION_RECURSIVE 90 #define HOTSPOT_CLASS_INITIALIZATION_concurrent HOTSPOT_CLASS_INITIALIZATION_CONCURRENT 91 #define HOTSPOT_CLASS_INITIALIZATION_erroneous HOTSPOT_CLASS_INITIALIZATION_ERRONEOUS 92 #define HOTSPOT_CLASS_INITIALIZATION_super__failed HOTSPOT_CLASS_INITIALIZATION_SUPER_FAILED 93 #define HOTSPOT_CLASS_INITIALIZATION_clinit HOTSPOT_CLASS_INITIALIZATION_CLINIT 94 #define HOTSPOT_CLASS_INITIALIZATION_error HOTSPOT_CLASS_INITIALIZATION_ERROR 95 #define HOTSPOT_CLASS_INITIALIZATION_end HOTSPOT_CLASS_INITIALIZATION_END 96 #define DTRACE_CLASSINIT_PROBE(type, thread_type) \ 97 { \ 98 char* data = NULL; \ 99 int len = 0; \ 100 Symbol* clss_name = name(); \ 101 if (clss_name != NULL) { \ 102 data = (char*)clss_name->bytes(); \ 103 len = clss_name->utf8_length(); \ 104 } \ 105 HOTSPOT_CLASS_INITIALIZATION_##type( \ 106 data, len, (void*)class_loader(), thread_type); \ 107 } 108 109 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait) \ 110 { \ 111 char* data = NULL; \ 112 int len = 0; \ 113 Symbol* clss_name = name(); \ 114 if (clss_name != NULL) { \ 115 data = (char*)clss_name->bytes(); \ 116 len = clss_name->utf8_length(); \ 117 } \ 118 HOTSPOT_CLASS_INITIALIZATION_##type( \ 119 data, len, (void*)class_loader(), thread_type, wait); \ 120 } 121 122 #else // ndef DTRACE_ENABLED 123 124 #define DTRACE_CLASSINIT_PROBE(type, thread_type) 125 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait) 126 127 #endif // ndef DTRACE_ENABLED 128 129 static inline bool is_class_loader(const Symbol* class_name, 130 const ClassFileParser& parser) { 131 assert(class_name != NULL, "invariant"); 132 133 if (class_name == vmSymbols::java_lang_ClassLoader()) { 134 return true; 135 } 136 137 if (SystemDictionary::ClassLoader_klass_loaded()) { 138 const Klass* const super_klass = parser.super_klass(); 139 if (super_klass != NULL) { 140 if (super_klass->is_subtype_of(SystemDictionary::ClassLoader_klass())) { 141 return true; 142 } 143 } 144 } 145 return false; 146 } 147 148 // called to verify that k is a member of this nest 149 bool InstanceKlass::has_nest_member(InstanceKlass* k, TRAPS) const { 150 if (_nest_members == NULL || _nest_members == Universe::the_empty_short_array()) { 151 if (log_is_enabled(Trace, class, nestmates)) { 152 ResourceMark rm(THREAD); 153 log_trace(class, nestmates)("Checked nest membership of %s in non-nest-host class %s", 154 k->external_name(), this->external_name()); 155 } 156 return false; 157 } 158 159 if (log_is_enabled(Trace, class, nestmates)) { 160 ResourceMark rm(THREAD); 161 log_trace(class, nestmates)("Checking nest membership of %s in %s", 162 k->external_name(), this->external_name()); 163 } 164 165 // Check names first and if they match then check actual klass. This avoids 166 // resolving anything unnecessarily. 167 for (int i = 0; i < _nest_members->length(); i++) { 168 int cp_index = _nest_members->at(i); 169 Symbol* name = _constants->klass_name_at(cp_index); 170 if (name == k->name()) { 171 log_trace(class, nestmates)("- Found it at nest_members[%d] => cp[%d]", i, cp_index); 172 173 // names match so check actual klass - this may trigger class loading if 174 // it doesn't match (but that should be impossible) 175 Klass* k2 = _constants->klass_at(cp_index, CHECK_false); 176 if (k2 == k) { 177 log_trace(class, nestmates)("- class is listed as a nest member"); 178 return true; 179 } else { 180 // same name but different klass! 181 log_trace(class, nestmates)(" - klass comparison failed!"); 182 // can't have different classes for the same name, so we're done 183 return false; 184 } 185 } 186 } 187 log_trace(class, nestmates)("- class is NOT a nest member!"); 188 return false; 189 } 190 191 // Return nest-host class, resolving, validating and saving it if needed. 192 // In cases where this is called from a thread that can not do classloading 193 // (such as a native JIT thread) then we simply return NULL, which in turn 194 // causes the access check to return false. Such code will retry the access 195 // from a more suitable environment later. 196 InstanceKlass* InstanceKlass::nest_host(Symbol* validationException, TRAPS) { 197 InstanceKlass* nest_host_k = _nest_host; 198 if (nest_host_k == NULL) { 199 // need to resolve and save our nest-host class. This could be attempted 200 // concurrently but as the result is idempotent and we don't use the class 201 // then we do not need any synchronization beyond what is implicitly used 202 // during class loading. 203 if (_nest_host_index != 0) { // we have a real nest_host 204 // Before trying to resolve check if we're in a suitable context 205 if (!THREAD->can_call_java() && !_constants->tag_at(_nest_host_index).is_klass()) { 206 if (log_is_enabled(Trace, class, nestmates)) { 207 ResourceMark rm(THREAD); 208 log_trace(class, nestmates)("Rejected resolution of nest-host of %s in unsuitable thread", 209 this->external_name()); 210 } 211 return NULL; 212 } 213 214 if (log_is_enabled(Trace, class, nestmates)) { 215 ResourceMark rm(THREAD); 216 log_trace(class, nestmates)("Resolving nest-host of %s using cp entry for %s", 217 this->external_name(), 218 _constants->klass_name_at(_nest_host_index)->as_C_string()); 219 } 220 221 Klass* k = _constants->klass_at(_nest_host_index, THREAD); 222 if (HAS_PENDING_EXCEPTION) { 223 Handle exc_h = Handle(THREAD, PENDING_EXCEPTION); 224 if (exc_h->is_a(SystemDictionary::NoClassDefFoundError_klass())) { 225 // throw a new CDNFE with the original as its cause, and a clear msg 226 ResourceMark rm(THREAD); 227 char buf[200]; 228 CLEAR_PENDING_EXCEPTION; 229 jio_snprintf(buf, sizeof(buf), 230 "Unable to load nest-host class (%s) of %s", 231 _constants->klass_name_at(_nest_host_index)->as_C_string(), 232 this->external_name()); 233 log_trace(class, nestmates)("%s - NoClassDefFoundError", buf); 234 THROW_MSG_CAUSE_NULL(vmSymbols::java_lang_NoClassDefFoundError(), buf, exc_h); 235 } 236 // All other exceptions pass through (OOME, StackOverflowError, LinkageErrors etc). 237 return NULL; 238 } 239 240 // A valid nest-host is an instance class in the current package that lists this 241 // class as a nest member. If any of these conditions are not met we post the 242 // requested exception type (if any) and return NULL 243 244 const char* error = NULL; 245 246 // JVMS 5.4.4 indicates package check comes first 247 if (is_same_class_package(k)) { 248 249 // Now check actual membership. We can't be a member if our "host" is 250 // not an instance class. 251 if (k->is_instance_klass()) { 252 nest_host_k = InstanceKlass::cast(k); 253 254 bool is_member = nest_host_k->has_nest_member(this, CHECK_NULL); 255 if (is_member) { 256 // save resolved nest-host value 257 _nest_host = nest_host_k; 258 259 if (log_is_enabled(Trace, class, nestmates)) { 260 ResourceMark rm(THREAD); 261 log_trace(class, nestmates)("Resolved nest-host of %s to %s", 262 this->external_name(), k->external_name()); 263 } 264 return nest_host_k; 265 } 266 } 267 error = "current type is not listed as a nest member"; 268 } else { 269 error = "types are in different packages"; 270 } 271 272 if (log_is_enabled(Trace, class, nestmates)) { 273 ResourceMark rm(THREAD); 274 log_trace(class, nestmates)("Type %s is not a nest member of resolved type %s: %s", 275 this->external_name(), 276 k->external_name(), 277 error); 278 } 279 280 if (validationException != NULL) { 281 ResourceMark rm(THREAD); 282 Exceptions::fthrow(THREAD_AND_LOCATION, 283 validationException, 284 "Type %s is not a nest member of %s: %s", 285 this->external_name(), 286 k->external_name(), 287 error 288 ); 289 } 290 return NULL; 291 } else { 292 if (log_is_enabled(Trace, class, nestmates)) { 293 ResourceMark rm(THREAD); 294 log_trace(class, nestmates)("Type %s is not part of a nest: setting nest-host to self", 295 this->external_name()); 296 } 297 // save resolved nest-host value 298 return (_nest_host = this); 299 } 300 } 301 return nest_host_k; 302 } 303 304 // check if 'this' and k are nestmates (same nest_host), or k is our nest_host, 305 // or we are k's nest_host - all of which is covered by comparing the two 306 // resolved_nest_hosts 307 bool InstanceKlass::has_nestmate_access_to(InstanceKlass* k, TRAPS) { 308 309 assert(this != k, "this should be handled by higher-level code"); 310 311 // Per JVMS 5.4.4 we first resolve and validate the current class, then 312 // the target class k. Resolution exceptions will be passed on by upper 313 // layers. IncompatibleClassChangeErrors from membership validation failures 314 // will also be passed through. 315 316 Symbol* icce = vmSymbols::java_lang_IncompatibleClassChangeError(); 317 InstanceKlass* cur_host = nest_host(icce, CHECK_false); 318 if (cur_host == NULL) { 319 return false; 320 } 321 322 Klass* k_nest_host = k->nest_host(icce, CHECK_false); 323 if (k_nest_host == NULL) { 324 return false; 325 } 326 327 bool access = (cur_host == k_nest_host); 328 329 if (log_is_enabled(Trace, class, nestmates)) { 330 ResourceMark rm(THREAD); 331 log_trace(class, nestmates)("Class %s does %shave nestmate access to %s", 332 this->external_name(), 333 access ? "" : "NOT ", 334 k->external_name()); 335 } 336 337 return access; 338 } 339 340 InstanceKlass* InstanceKlass::allocate_instance_klass(const ClassFileParser& parser, TRAPS) { 341 const int size = InstanceKlass::size(parser.vtable_size(), 342 parser.itable_size(), 343 nonstatic_oop_map_size(parser.total_oop_map_count()), 344 parser.is_interface(), 345 parser.is_anonymous(), 346 should_store_fingerprint(parser.is_anonymous())); 347 348 const Symbol* const class_name = parser.class_name(); 349 assert(class_name != NULL, "invariant"); 350 ClassLoaderData* loader_data = parser.loader_data(); 351 assert(loader_data != NULL, "invariant"); 352 353 InstanceKlass* ik; 354 355 // Allocation 356 if (REF_NONE == parser.reference_type()) { 357 if (class_name == vmSymbols::java_lang_Class()) { 358 // mirror 359 ik = new (loader_data, size, THREAD) InstanceMirrorKlass(parser); 360 } 361 else if (is_class_loader(class_name, parser)) { 362 // class loader 363 ik = new (loader_data, size, THREAD) InstanceClassLoaderKlass(parser); 364 } else { 365 // normal 366 ik = new (loader_data, size, THREAD) InstanceKlass(parser, InstanceKlass::_misc_kind_other); 367 } 368 } else { 369 // reference 370 ik = new (loader_data, size, THREAD) InstanceRefKlass(parser); 371 } 372 373 // Check for pending exception before adding to the loader data and incrementing 374 // class count. Can get OOM here. 375 if (HAS_PENDING_EXCEPTION) { 376 return NULL; 377 } 378 379 return ik; 380 } 381 382 383 // copy method ordering from resource area to Metaspace 384 void InstanceKlass::copy_method_ordering(const intArray* m, TRAPS) { 385 if (m != NULL) { 386 // allocate a new array and copy contents (memcpy?) 387 _method_ordering = MetadataFactory::new_array<int>(class_loader_data(), m->length(), CHECK); 388 for (int i = 0; i < m->length(); i++) { 389 _method_ordering->at_put(i, m->at(i)); 390 } 391 } else { 392 _method_ordering = Universe::the_empty_int_array(); 393 } 394 } 395 396 // create a new array of vtable_indices for default methods 397 Array<int>* InstanceKlass::create_new_default_vtable_indices(int len, TRAPS) { 398 Array<int>* vtable_indices = MetadataFactory::new_array<int>(class_loader_data(), len, CHECK_NULL); 399 assert(default_vtable_indices() == NULL, "only create once"); 400 set_default_vtable_indices(vtable_indices); 401 return vtable_indices; 402 } 403 404 InstanceKlass::InstanceKlass(const ClassFileParser& parser, unsigned kind) : 405 _static_field_size(parser.static_field_size()), 406 _nonstatic_oop_map_size(nonstatic_oop_map_size(parser.total_oop_map_count())), 407 _itable_len(parser.itable_size()), 408 _reference_type(parser.reference_type()), 409 _nest_members(NULL), 410 _nest_host_index(0), 411 _nest_host(NULL) { 412 set_vtable_length(parser.vtable_size()); 413 set_kind(kind); 414 set_access_flags(parser.access_flags()); 415 set_is_anonymous(parser.is_anonymous()); 416 set_layout_helper(Klass::instance_layout_helper(parser.layout_size(), 417 false)); 418 419 assert(NULL == _methods, "underlying memory not zeroed?"); 420 assert(is_instance_klass(), "is layout incorrect?"); 421 assert(size_helper() == parser.layout_size(), "incorrect size_helper?"); 422 } 423 424 void InstanceKlass::deallocate_methods(ClassLoaderData* loader_data, 425 Array<Method*>* methods) { 426 if (methods != NULL && methods != Universe::the_empty_method_array() && 427 !methods->is_shared()) { 428 for (int i = 0; i < methods->length(); i++) { 429 Method* method = methods->at(i); 430 if (method == NULL) continue; // maybe null if error processing 431 // Only want to delete methods that are not executing for RedefineClasses. 432 // The previous version will point to them so they're not totally dangling 433 assert (!method->on_stack(), "shouldn't be called with methods on stack"); 434 MetadataFactory::free_metadata(loader_data, method); 435 } 436 MetadataFactory::free_array<Method*>(loader_data, methods); 437 } 438 } 439 440 void InstanceKlass::deallocate_interfaces(ClassLoaderData* loader_data, 441 const Klass* super_klass, 442 Array<Klass*>* local_interfaces, 443 Array<Klass*>* transitive_interfaces) { 444 // Only deallocate transitive interfaces if not empty, same as super class 445 // or same as local interfaces. See code in parseClassFile. 446 Array<Klass*>* ti = transitive_interfaces; 447 if (ti != Universe::the_empty_klass_array() && ti != local_interfaces) { 448 // check that the interfaces don't come from super class 449 Array<Klass*>* sti = (super_klass == NULL) ? NULL : 450 InstanceKlass::cast(super_klass)->transitive_interfaces(); 451 if (ti != sti && ti != NULL && !ti->is_shared()) { 452 MetadataFactory::free_array<Klass*>(loader_data, ti); 453 } 454 } 455 456 // local interfaces can be empty 457 if (local_interfaces != Universe::the_empty_klass_array() && 458 local_interfaces != NULL && !local_interfaces->is_shared()) { 459 MetadataFactory::free_array<Klass*>(loader_data, local_interfaces); 460 } 461 } 462 463 // This function deallocates the metadata and C heap pointers that the 464 // InstanceKlass points to. 465 void InstanceKlass::deallocate_contents(ClassLoaderData* loader_data) { 466 467 // Orphan the mirror first, CMS thinks it's still live. 468 if (java_mirror() != NULL) { 469 java_lang_Class::set_klass(java_mirror(), NULL); 470 } 471 472 // Also remove mirror from handles 473 loader_data->remove_handle(_java_mirror); 474 475 // Need to take this class off the class loader data list. 476 loader_data->remove_class(this); 477 478 // The array_klass for this class is created later, after error handling. 479 // For class redefinition, we keep the original class so this scratch class 480 // doesn't have an array class. Either way, assert that there is nothing 481 // to deallocate. 482 assert(array_klasses() == NULL, "array classes shouldn't be created for this class yet"); 483 484 // Release C heap allocated data that this might point to, which includes 485 // reference counting symbol names. 486 release_C_heap_structures(); 487 488 deallocate_methods(loader_data, methods()); 489 set_methods(NULL); 490 491 if (method_ordering() != NULL && 492 method_ordering() != Universe::the_empty_int_array() && 493 !method_ordering()->is_shared()) { 494 MetadataFactory::free_array<int>(loader_data, method_ordering()); 495 } 496 set_method_ordering(NULL); 497 498 // default methods can be empty 499 if (default_methods() != NULL && 500 default_methods() != Universe::the_empty_method_array() && 501 !default_methods()->is_shared()) { 502 MetadataFactory::free_array<Method*>(loader_data, default_methods()); 503 } 504 // Do NOT deallocate the default methods, they are owned by superinterfaces. 505 set_default_methods(NULL); 506 507 // default methods vtable indices can be empty 508 if (default_vtable_indices() != NULL && 509 !default_vtable_indices()->is_shared()) { 510 MetadataFactory::free_array<int>(loader_data, default_vtable_indices()); 511 } 512 set_default_vtable_indices(NULL); 513 514 515 // This array is in Klass, but remove it with the InstanceKlass since 516 // this place would be the only caller and it can share memory with transitive 517 // interfaces. 518 if (secondary_supers() != NULL && 519 secondary_supers() != Universe::the_empty_klass_array() && 520 secondary_supers() != transitive_interfaces() && 521 !secondary_supers()->is_shared()) { 522 MetadataFactory::free_array<Klass*>(loader_data, secondary_supers()); 523 } 524 set_secondary_supers(NULL); 525 526 deallocate_interfaces(loader_data, super(), local_interfaces(), transitive_interfaces()); 527 set_transitive_interfaces(NULL); 528 set_local_interfaces(NULL); 529 530 if (fields() != NULL && !fields()->is_shared()) { 531 MetadataFactory::free_array<jushort>(loader_data, fields()); 532 } 533 set_fields(NULL, 0); 534 535 // If a method from a redefined class is using this constant pool, don't 536 // delete it, yet. The new class's previous version will point to this. 537 if (constants() != NULL) { 538 assert (!constants()->on_stack(), "shouldn't be called if anything is onstack"); 539 if (!constants()->is_shared()) { 540 MetadataFactory::free_metadata(loader_data, constants()); 541 } 542 // Delete any cached resolution errors for the constant pool 543 SystemDictionary::delete_resolution_error(constants()); 544 545 set_constants(NULL); 546 } 547 548 if (inner_classes() != NULL && 549 inner_classes() != Universe::the_empty_short_array() && 550 !inner_classes()->is_shared()) { 551 MetadataFactory::free_array<jushort>(loader_data, inner_classes()); 552 } 553 set_inner_classes(NULL); 554 555 if (nest_members() != NULL && 556 nest_members() != Universe::the_empty_short_array() && 557 !nest_members()->is_shared()) { 558 MetadataFactory::free_array<jushort>(loader_data, nest_members()); 559 } 560 set_nest_members(NULL); 561 562 // We should deallocate the Annotations instance if it's not in shared spaces. 563 if (annotations() != NULL && !annotations()->is_shared()) { 564 MetadataFactory::free_metadata(loader_data, annotations()); 565 } 566 set_annotations(NULL); 567 } 568 569 bool InstanceKlass::should_be_initialized() const { 570 return !is_initialized(); 571 } 572 573 klassItable InstanceKlass::itable() const { 574 return klassItable(const_cast<InstanceKlass*>(this)); 575 } 576 577 void InstanceKlass::eager_initialize(Thread *thread) { 578 if (!EagerInitialization) return; 579 580 if (this->is_not_initialized()) { 581 // abort if the the class has a class initializer 582 if (this->class_initializer() != NULL) return; 583 584 // abort if it is java.lang.Object (initialization is handled in genesis) 585 Klass* super_klass = super(); 586 if (super_klass == NULL) return; 587 588 // abort if the super class should be initialized 589 if (!InstanceKlass::cast(super_klass)->is_initialized()) return; 590 591 // call body to expose the this pointer 592 eager_initialize_impl(); 593 } 594 } 595 596 // JVMTI spec thinks there are signers and protection domain in the 597 // instanceKlass. These accessors pretend these fields are there. 598 // The hprof specification also thinks these fields are in InstanceKlass. 599 oop InstanceKlass::protection_domain() const { 600 // return the protection_domain from the mirror 601 return java_lang_Class::protection_domain(java_mirror()); 602 } 603 604 // To remove these from requires an incompatible change and CCC request. 605 objArrayOop InstanceKlass::signers() const { 606 // return the signers from the mirror 607 return java_lang_Class::signers(java_mirror()); 608 } 609 610 oop InstanceKlass::init_lock() const { 611 // return the init lock from the mirror 612 oop lock = java_lang_Class::init_lock(java_mirror()); 613 // Prevent reordering with any access of initialization state 614 OrderAccess::loadload(); 615 assert((oop)lock != NULL || !is_not_initialized(), // initialized or in_error state 616 "only fully initialized state can have a null lock"); 617 return lock; 618 } 619 620 // Set the initialization lock to null so the object can be GC'ed. Any racing 621 // threads to get this lock will see a null lock and will not lock. 622 // That's okay because they all check for initialized state after getting 623 // the lock and return. 624 void InstanceKlass::fence_and_clear_init_lock() { 625 // make sure previous stores are all done, notably the init_state. 626 OrderAccess::storestore(); 627 java_lang_Class::set_init_lock(java_mirror(), NULL); 628 assert(!is_not_initialized(), "class must be initialized now"); 629 } 630 631 void InstanceKlass::eager_initialize_impl() { 632 EXCEPTION_MARK; 633 HandleMark hm(THREAD); 634 Handle h_init_lock(THREAD, init_lock()); 635 ObjectLocker ol(h_init_lock, THREAD, h_init_lock() != NULL); 636 637 // abort if someone beat us to the initialization 638 if (!is_not_initialized()) return; // note: not equivalent to is_initialized() 639 640 ClassState old_state = init_state(); 641 link_class_impl(true, THREAD); 642 if (HAS_PENDING_EXCEPTION) { 643 CLEAR_PENDING_EXCEPTION; 644 // Abort if linking the class throws an exception. 645 646 // Use a test to avoid redundantly resetting the state if there's 647 // no change. Set_init_state() asserts that state changes make 648 // progress, whereas here we might just be spinning in place. 649 if (old_state != _init_state) 650 set_init_state(old_state); 651 } else { 652 // linking successfull, mark class as initialized 653 set_init_state(fully_initialized); 654 fence_and_clear_init_lock(); 655 // trace 656 if (log_is_enabled(Info, class, init)) { 657 ResourceMark rm(THREAD); 658 log_info(class, init)("[Initialized %s without side effects]", external_name()); 659 } 660 } 661 } 662 663 664 // See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization 665 // process. The step comments refers to the procedure described in that section. 666 // Note: implementation moved to static method to expose the this pointer. 667 void InstanceKlass::initialize(TRAPS) { 668 if (this->should_be_initialized()) { 669 initialize_impl(CHECK); 670 // Note: at this point the class may be initialized 671 // OR it may be in the state of being initialized 672 // in case of recursive initialization! 673 } else { 674 assert(is_initialized(), "sanity check"); 675 } 676 } 677 678 679 bool InstanceKlass::verify_code(bool throw_verifyerror, TRAPS) { 680 // 1) Verify the bytecodes 681 Verifier::Mode mode = 682 throw_verifyerror ? Verifier::ThrowException : Verifier::NoException; 683 return Verifier::verify(this, mode, should_verify_class(), THREAD); 684 } 685 686 687 // Used exclusively by the shared spaces dump mechanism to prevent 688 // classes mapped into the shared regions in new VMs from appearing linked. 689 690 void InstanceKlass::unlink_class() { 691 assert(is_linked(), "must be linked"); 692 _init_state = loaded; 693 } 694 695 void InstanceKlass::link_class(TRAPS) { 696 assert(is_loaded(), "must be loaded"); 697 if (!is_linked()) { 698 link_class_impl(true, CHECK); 699 } 700 } 701 702 // Called to verify that a class can link during initialization, without 703 // throwing a VerifyError. 704 bool InstanceKlass::link_class_or_fail(TRAPS) { 705 assert(is_loaded(), "must be loaded"); 706 if (!is_linked()) { 707 link_class_impl(false, CHECK_false); 708 } 709 return is_linked(); 710 } 711 712 bool InstanceKlass::link_class_impl(bool throw_verifyerror, TRAPS) { 713 if (DumpSharedSpaces && is_in_error_state()) { 714 // This is for CDS dumping phase only -- we use the in_error_state to indicate that 715 // the class has failed verification. Throwing the NoClassDefFoundError here is just 716 // a convenient way to stop repeat attempts to verify the same (bad) class. 717 // 718 // Note that the NoClassDefFoundError is not part of the JLS, and should not be thrown 719 // if we are executing Java code. This is not a problem for CDS dumping phase since 720 // it doesn't execute any Java code. 721 ResourceMark rm(THREAD); 722 Exceptions::fthrow(THREAD_AND_LOCATION, 723 vmSymbols::java_lang_NoClassDefFoundError(), 724 "Class %s, or one of its supertypes, failed class initialization", 725 external_name()); 726 return false; 727 } 728 // return if already verified 729 if (is_linked()) { 730 return true; 731 } 732 733 // Timing 734 // timer handles recursion 735 assert(THREAD->is_Java_thread(), "non-JavaThread in link_class_impl"); 736 JavaThread* jt = (JavaThread*)THREAD; 737 738 // link super class before linking this class 739 Klass* super_klass = super(); 740 if (super_klass != NULL) { 741 if (super_klass->is_interface()) { // check if super class is an interface 742 ResourceMark rm(THREAD); 743 Exceptions::fthrow( 744 THREAD_AND_LOCATION, 745 vmSymbols::java_lang_IncompatibleClassChangeError(), 746 "class %s has interface %s as super class", 747 external_name(), 748 super_klass->external_name() 749 ); 750 return false; 751 } 752 753 InstanceKlass* ik_super = InstanceKlass::cast(super_klass); 754 ik_super->link_class_impl(throw_verifyerror, CHECK_false); 755 } 756 757 // link all interfaces implemented by this class before linking this class 758 Array<Klass*>* interfaces = local_interfaces(); 759 int num_interfaces = interfaces->length(); 760 for (int index = 0; index < num_interfaces; index++) { 761 InstanceKlass* interk = InstanceKlass::cast(interfaces->at(index)); 762 interk->link_class_impl(throw_verifyerror, CHECK_false); 763 } 764 765 // in case the class is linked in the process of linking its superclasses 766 if (is_linked()) { 767 return true; 768 } 769 770 // trace only the link time for this klass that includes 771 // the verification time 772 PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(), 773 ClassLoader::perf_class_link_selftime(), 774 ClassLoader::perf_classes_linked(), 775 jt->get_thread_stat()->perf_recursion_counts_addr(), 776 jt->get_thread_stat()->perf_timers_addr(), 777 PerfClassTraceTime::CLASS_LINK); 778 779 // verification & rewriting 780 { 781 HandleMark hm(THREAD); 782 Handle h_init_lock(THREAD, init_lock()); 783 ObjectLocker ol(h_init_lock, THREAD, h_init_lock() != NULL); 784 // rewritten will have been set if loader constraint error found 785 // on an earlier link attempt 786 // don't verify or rewrite if already rewritten 787 // 788 789 if (!is_linked()) { 790 if (!is_rewritten()) { 791 { 792 bool verify_ok = verify_code(throw_verifyerror, THREAD); 793 if (!verify_ok) { 794 return false; 795 } 796 } 797 798 // Just in case a side-effect of verify linked this class already 799 // (which can sometimes happen since the verifier loads classes 800 // using custom class loaders, which are free to initialize things) 801 if (is_linked()) { 802 return true; 803 } 804 805 // also sets rewritten 806 rewrite_class(CHECK_false); 807 } else if (is_shared()) { 808 SystemDictionaryShared::check_verification_constraints(this, CHECK_false); 809 } 810 811 // relocate jsrs and link methods after they are all rewritten 812 link_methods(CHECK_false); 813 814 // Initialize the vtable and interface table after 815 // methods have been rewritten since rewrite may 816 // fabricate new Method*s. 817 // also does loader constraint checking 818 // 819 // initialize_vtable and initialize_itable need to be rerun for 820 // a shared class if the class is not loaded by the NULL classloader. 821 ClassLoaderData * loader_data = class_loader_data(); 822 if (!(is_shared() && 823 loader_data->is_the_null_class_loader_data())) { 824 ResourceMark rm(THREAD); 825 vtable().initialize_vtable(true, CHECK_false); 826 itable().initialize_itable(true, CHECK_false); 827 } 828 #ifdef ASSERT 829 else { 830 vtable().verify(tty, true); 831 // In case itable verification is ever added. 832 // itable().verify(tty, true); 833 } 834 #endif 835 set_init_state(linked); 836 if (JvmtiExport::should_post_class_prepare()) { 837 Thread *thread = THREAD; 838 assert(thread->is_Java_thread(), "thread->is_Java_thread()"); 839 JvmtiExport::post_class_prepare((JavaThread *) thread, this); 840 } 841 } 842 } 843 return true; 844 } 845 846 // Rewrite the byte codes of all of the methods of a class. 847 // The rewriter must be called exactly once. Rewriting must happen after 848 // verification but before the first method of the class is executed. 849 void InstanceKlass::rewrite_class(TRAPS) { 850 assert(is_loaded(), "must be loaded"); 851 if (is_rewritten()) { 852 assert(is_shared(), "rewriting an unshared class?"); 853 return; 854 } 855 Rewriter::rewrite(this, CHECK); 856 set_rewritten(); 857 } 858 859 // Now relocate and link method entry points after class is rewritten. 860 // This is outside is_rewritten flag. In case of an exception, it can be 861 // executed more than once. 862 void InstanceKlass::link_methods(TRAPS) { 863 int len = methods()->length(); 864 for (int i = len-1; i >= 0; i--) { 865 methodHandle m(THREAD, methods()->at(i)); 866 867 // Set up method entry points for compiler and interpreter . 868 m->link_method(m, CHECK); 869 } 870 } 871 872 // Eagerly initialize superinterfaces that declare default methods (concrete instance: any access) 873 void InstanceKlass::initialize_super_interfaces(TRAPS) { 874 assert (has_nonstatic_concrete_methods(), "caller should have checked this"); 875 for (int i = 0; i < local_interfaces()->length(); ++i) { 876 Klass* iface = local_interfaces()->at(i); 877 InstanceKlass* ik = InstanceKlass::cast(iface); 878 879 // Initialization is depth first search ie. we start with top of the inheritance tree 880 // has_nonstatic_concrete_methods drives searching superinterfaces since it 881 // means has_nonstatic_concrete_methods in its superinterface hierarchy 882 if (ik->has_nonstatic_concrete_methods()) { 883 ik->initialize_super_interfaces(CHECK); 884 } 885 886 // Only initialize() interfaces that "declare" concrete methods. 887 if (ik->should_be_initialized() && ik->declares_nonstatic_concrete_methods()) { 888 ik->initialize(CHECK); 889 } 890 } 891 } 892 893 void InstanceKlass::initialize_impl(TRAPS) { 894 HandleMark hm(THREAD); 895 896 // Make sure klass is linked (verified) before initialization 897 // A class could already be verified, since it has been reflected upon. 898 link_class(CHECK); 899 900 DTRACE_CLASSINIT_PROBE(required, -1); 901 902 bool wait = false; 903 904 // refer to the JVM book page 47 for description of steps 905 // Step 1 906 { 907 Handle h_init_lock(THREAD, init_lock()); 908 ObjectLocker ol(h_init_lock, THREAD, h_init_lock() != NULL); 909 910 Thread *self = THREAD; // it's passed the current thread 911 912 // Step 2 913 // If we were to use wait() instead of waitInterruptibly() then 914 // we might end up throwing IE from link/symbol resolution sites 915 // that aren't expected to throw. This would wreak havoc. See 6320309. 916 while(is_being_initialized() && !is_reentrant_initialization(self)) { 917 wait = true; 918 ol.waitUninterruptibly(CHECK); 919 } 920 921 // Step 3 922 if (is_being_initialized() && is_reentrant_initialization(self)) { 923 DTRACE_CLASSINIT_PROBE_WAIT(recursive, -1, wait); 924 return; 925 } 926 927 // Step 4 928 if (is_initialized()) { 929 DTRACE_CLASSINIT_PROBE_WAIT(concurrent, -1, wait); 930 return; 931 } 932 933 // Step 5 934 if (is_in_error_state()) { 935 DTRACE_CLASSINIT_PROBE_WAIT(erroneous, -1, wait); 936 ResourceMark rm(THREAD); 937 const char* desc = "Could not initialize class "; 938 const char* className = external_name(); 939 size_t msglen = strlen(desc) + strlen(className) + 1; 940 char* message = NEW_RESOURCE_ARRAY(char, msglen); 941 if (NULL == message) { 942 // Out of memory: can't create detailed error message 943 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), className); 944 } else { 945 jio_snprintf(message, msglen, "%s%s", desc, className); 946 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), message); 947 } 948 } 949 950 // Step 6 951 set_init_state(being_initialized); 952 set_init_thread(self); 953 } 954 955 // Step 7 956 // Next, if C is a class rather than an interface, initialize it's super class and super 957 // interfaces. 958 if (!is_interface()) { 959 Klass* super_klass = super(); 960 if (super_klass != NULL && super_klass->should_be_initialized()) { 961 super_klass->initialize(THREAD); 962 } 963 // If C implements any interface that declares a non-static, concrete method, 964 // the initialization of C triggers initialization of its super interfaces. 965 // Only need to recurse if has_nonstatic_concrete_methods which includes declaring and 966 // having a superinterface that declares, non-static, concrete methods 967 if (!HAS_PENDING_EXCEPTION && has_nonstatic_concrete_methods()) { 968 initialize_super_interfaces(THREAD); 969 } 970 971 // If any exceptions, complete abruptly, throwing the same exception as above. 972 if (HAS_PENDING_EXCEPTION) { 973 Handle e(THREAD, PENDING_EXCEPTION); 974 CLEAR_PENDING_EXCEPTION; 975 { 976 EXCEPTION_MARK; 977 // Locks object, set state, and notify all waiting threads 978 set_initialization_state_and_notify(initialization_error, THREAD); 979 CLEAR_PENDING_EXCEPTION; 980 } 981 DTRACE_CLASSINIT_PROBE_WAIT(super__failed, -1, wait); 982 THROW_OOP(e()); 983 } 984 } 985 986 987 // Look for aot compiled methods for this klass, including class initializer. 988 AOTLoader::load_for_klass(this, THREAD); 989 990 // Step 8 991 { 992 assert(THREAD->is_Java_thread(), "non-JavaThread in initialize_impl"); 993 JavaThread* jt = (JavaThread*)THREAD; 994 DTRACE_CLASSINIT_PROBE_WAIT(clinit, -1, wait); 995 // Timer includes any side effects of class initialization (resolution, 996 // etc), but not recursive entry into call_class_initializer(). 997 PerfClassTraceTime timer(ClassLoader::perf_class_init_time(), 998 ClassLoader::perf_class_init_selftime(), 999 ClassLoader::perf_classes_inited(), 1000 jt->get_thread_stat()->perf_recursion_counts_addr(), 1001 jt->get_thread_stat()->perf_timers_addr(), 1002 PerfClassTraceTime::CLASS_CLINIT); 1003 call_class_initializer(THREAD); 1004 } 1005 1006 // Step 9 1007 if (!HAS_PENDING_EXCEPTION) { 1008 set_initialization_state_and_notify(fully_initialized, CHECK); 1009 { 1010 debug_only(vtable().verify(tty, true);) 1011 } 1012 } 1013 else { 1014 // Step 10 and 11 1015 Handle e(THREAD, PENDING_EXCEPTION); 1016 CLEAR_PENDING_EXCEPTION; 1017 // JVMTI has already reported the pending exception 1018 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError 1019 JvmtiExport::clear_detected_exception((JavaThread*)THREAD); 1020 { 1021 EXCEPTION_MARK; 1022 set_initialization_state_and_notify(initialization_error, THREAD); 1023 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, class initialization error is thrown below 1024 // JVMTI has already reported the pending exception 1025 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError 1026 JvmtiExport::clear_detected_exception((JavaThread*)THREAD); 1027 } 1028 DTRACE_CLASSINIT_PROBE_WAIT(error, -1, wait); 1029 if (e->is_a(SystemDictionary::Error_klass())) { 1030 THROW_OOP(e()); 1031 } else { 1032 JavaCallArguments args(e); 1033 THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(), 1034 vmSymbols::throwable_void_signature(), 1035 &args); 1036 } 1037 } 1038 DTRACE_CLASSINIT_PROBE_WAIT(end, -1, wait); 1039 } 1040 1041 1042 void InstanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) { 1043 Handle h_init_lock(THREAD, init_lock()); 1044 if (h_init_lock() != NULL) { 1045 ObjectLocker ol(h_init_lock, THREAD); 1046 set_init_state(state); 1047 fence_and_clear_init_lock(); 1048 ol.notify_all(CHECK); 1049 } else { 1050 assert(h_init_lock() != NULL, "The initialization state should never be set twice"); 1051 set_init_state(state); 1052 } 1053 } 1054 1055 // The embedded _implementor field can only record one implementor. 1056 // When there are more than one implementors, the _implementor field 1057 // is set to the interface Klass* itself. Following are the possible 1058 // values for the _implementor field: 1059 // NULL - no implementor 1060 // implementor Klass* - one implementor 1061 // self - more than one implementor 1062 // 1063 // The _implementor field only exists for interfaces. 1064 void InstanceKlass::add_implementor(Klass* k) { 1065 assert(Compile_lock->owned_by_self(), ""); 1066 assert(is_interface(), "not interface"); 1067 // Filter out my subinterfaces. 1068 // (Note: Interfaces are never on the subklass list.) 1069 if (InstanceKlass::cast(k)->is_interface()) return; 1070 1071 // Filter out subclasses whose supers already implement me. 1072 // (Note: CHA must walk subclasses of direct implementors 1073 // in order to locate indirect implementors.) 1074 Klass* sk = k->super(); 1075 if (sk != NULL && InstanceKlass::cast(sk)->implements_interface(this)) 1076 // We only need to check one immediate superclass, since the 1077 // implements_interface query looks at transitive_interfaces. 1078 // Any supers of the super have the same (or fewer) transitive_interfaces. 1079 return; 1080 1081 Klass* ik = implementor(); 1082 if (ik == NULL) { 1083 set_implementor(k); 1084 } else if (ik != this) { 1085 // There is already an implementor. Use itself as an indicator of 1086 // more than one implementors. 1087 set_implementor(this); 1088 } 1089 1090 // The implementor also implements the transitive_interfaces 1091 for (int index = 0; index < local_interfaces()->length(); index++) { 1092 InstanceKlass::cast(local_interfaces()->at(index))->add_implementor(k); 1093 } 1094 } 1095 1096 void InstanceKlass::init_implementor() { 1097 if (is_interface()) { 1098 set_implementor(NULL); 1099 } 1100 } 1101 1102 1103 void InstanceKlass::process_interfaces(Thread *thread) { 1104 // link this class into the implementors list of every interface it implements 1105 for (int i = local_interfaces()->length() - 1; i >= 0; i--) { 1106 assert(local_interfaces()->at(i)->is_klass(), "must be a klass"); 1107 InstanceKlass* interf = InstanceKlass::cast(local_interfaces()->at(i)); 1108 assert(interf->is_interface(), "expected interface"); 1109 interf->add_implementor(this); 1110 } 1111 } 1112 1113 bool InstanceKlass::can_be_primary_super_slow() const { 1114 if (is_interface()) 1115 return false; 1116 else 1117 return Klass::can_be_primary_super_slow(); 1118 } 1119 1120 GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots, 1121 Array<Klass*>* transitive_interfaces) { 1122 // The secondaries are the implemented interfaces. 1123 Array<Klass*>* interfaces = transitive_interfaces; 1124 int num_secondaries = num_extra_slots + interfaces->length(); 1125 if (num_secondaries == 0) { 1126 // Must share this for correct bootstrapping! 1127 set_secondary_supers(Universe::the_empty_klass_array()); 1128 return NULL; 1129 } else if (num_extra_slots == 0) { 1130 // The secondary super list is exactly the same as the transitive interfaces. 1131 // Redefine classes has to be careful not to delete this! 1132 set_secondary_supers(interfaces); 1133 return NULL; 1134 } else { 1135 // Copy transitive interfaces to a temporary growable array to be constructed 1136 // into the secondary super list with extra slots. 1137 GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length()); 1138 for (int i = 0; i < interfaces->length(); i++) { 1139 secondaries->push(interfaces->at(i)); 1140 } 1141 return secondaries; 1142 } 1143 } 1144 1145 bool InstanceKlass::compute_is_subtype_of(Klass* k) { 1146 if (k->is_interface()) { 1147 return implements_interface(k); 1148 } else { 1149 return Klass::compute_is_subtype_of(k); 1150 } 1151 } 1152 1153 bool InstanceKlass::implements_interface(Klass* k) const { 1154 if (this == k) return true; 1155 assert(k->is_interface(), "should be an interface class"); 1156 for (int i = 0; i < transitive_interfaces()->length(); i++) { 1157 if (transitive_interfaces()->at(i) == k) { 1158 return true; 1159 } 1160 } 1161 return false; 1162 } 1163 1164 bool InstanceKlass::is_same_or_direct_interface(Klass *k) const { 1165 // Verify direct super interface 1166 if (this == k) return true; 1167 assert(k->is_interface(), "should be an interface class"); 1168 for (int i = 0; i < local_interfaces()->length(); i++) { 1169 if (local_interfaces()->at(i) == k) { 1170 return true; 1171 } 1172 } 1173 return false; 1174 } 1175 1176 objArrayOop InstanceKlass::allocate_objArray(int n, int length, TRAPS) { 1177 if (length < 0) { 1178 THROW_MSG_0(vmSymbols::java_lang_NegativeArraySizeException(), err_msg("%d", length)); 1179 } 1180 if (length > arrayOopDesc::max_array_length(T_OBJECT)) { 1181 report_java_out_of_memory("Requested array size exceeds VM limit"); 1182 JvmtiExport::post_array_size_exhausted(); 1183 THROW_OOP_0(Universe::out_of_memory_error_array_size()); 1184 } 1185 int size = objArrayOopDesc::object_size(length); 1186 Klass* ak = array_klass(n, CHECK_NULL); 1187 objArrayOop o = 1188 (objArrayOop)CollectedHeap::array_allocate(ak, size, length, CHECK_NULL); 1189 return o; 1190 } 1191 1192 instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) { 1193 if (TraceFinalizerRegistration) { 1194 tty->print("Registered "); 1195 i->print_value_on(tty); 1196 tty->print_cr(" (" INTPTR_FORMAT ") as finalizable", p2i(i)); 1197 } 1198 instanceHandle h_i(THREAD, i); 1199 // Pass the handle as argument, JavaCalls::call expects oop as jobjects 1200 JavaValue result(T_VOID); 1201 JavaCallArguments args(h_i); 1202 methodHandle mh (THREAD, Universe::finalizer_register_method()); 1203 JavaCalls::call(&result, mh, &args, CHECK_NULL); 1204 return h_i(); 1205 } 1206 1207 instanceOop InstanceKlass::allocate_instance(TRAPS) { 1208 bool has_finalizer_flag = has_finalizer(); // Query before possible GC 1209 int size = size_helper(); // Query before forming handle. 1210 1211 instanceOop i; 1212 1213 i = (instanceOop)CollectedHeap::obj_allocate(this, size, CHECK_NULL); 1214 if (has_finalizer_flag && !RegisterFinalizersAtInit) { 1215 i = register_finalizer(i, CHECK_NULL); 1216 } 1217 return i; 1218 } 1219 1220 instanceHandle InstanceKlass::allocate_instance_handle(TRAPS) { 1221 return instanceHandle(THREAD, allocate_instance(THREAD)); 1222 } 1223 1224 void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) { 1225 if (is_interface() || is_abstract()) { 1226 ResourceMark rm(THREAD); 1227 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError() 1228 : vmSymbols::java_lang_InstantiationException(), external_name()); 1229 } 1230 if (this == SystemDictionary::Class_klass()) { 1231 ResourceMark rm(THREAD); 1232 THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError() 1233 : vmSymbols::java_lang_IllegalAccessException(), external_name()); 1234 } 1235 } 1236 1237 Klass* InstanceKlass::array_klass_impl(bool or_null, int n, TRAPS) { 1238 // Need load-acquire for lock-free read 1239 if (array_klasses_acquire() == NULL) { 1240 if (or_null) return NULL; 1241 1242 ResourceMark rm; 1243 JavaThread *jt = (JavaThread *)THREAD; 1244 { 1245 // Atomic creation of array_klasses 1246 MutexLocker mc(Compile_lock, THREAD); // for vtables 1247 MutexLocker ma(MultiArray_lock, THREAD); 1248 1249 // Check if update has already taken place 1250 if (array_klasses() == NULL) { 1251 Klass* k = ObjArrayKlass::allocate_objArray_klass(class_loader_data(), 1, this, CHECK_NULL); 1252 // use 'release' to pair with lock-free load 1253 release_set_array_klasses(k); 1254 } 1255 } 1256 } 1257 // _this will always be set at this point 1258 ObjArrayKlass* oak = (ObjArrayKlass*)array_klasses(); 1259 if (or_null) { 1260 return oak->array_klass_or_null(n); 1261 } 1262 return oak->array_klass(n, THREAD); 1263 } 1264 1265 Klass* InstanceKlass::array_klass_impl(bool or_null, TRAPS) { 1266 return array_klass_impl(or_null, 1, THREAD); 1267 } 1268 1269 static int call_class_initializer_counter = 0; // for debugging 1270 1271 Method* InstanceKlass::class_initializer() const { 1272 Method* clinit = find_method( 1273 vmSymbols::class_initializer_name(), vmSymbols::void_method_signature()); 1274 if (clinit != NULL && clinit->has_valid_initializer_flags()) { 1275 return clinit; 1276 } 1277 return NULL; 1278 } 1279 1280 void InstanceKlass::call_class_initializer(TRAPS) { 1281 if (ReplayCompiles && 1282 (ReplaySuppressInitializers == 1 || 1283 (ReplaySuppressInitializers >= 2 && class_loader() != NULL))) { 1284 // Hide the existence of the initializer for the purpose of replaying the compile 1285 return; 1286 } 1287 1288 methodHandle h_method(THREAD, class_initializer()); 1289 assert(!is_initialized(), "we cannot initialize twice"); 1290 LogTarget(Info, class, init) lt; 1291 if (lt.is_enabled()) { 1292 ResourceMark rm; 1293 LogStream ls(lt); 1294 ls.print("%d Initializing ", call_class_initializer_counter++); 1295 name()->print_value_on(&ls); 1296 ls.print_cr("%s (" INTPTR_FORMAT ")", h_method() == NULL ? "(no method)" : "", p2i(this)); 1297 } 1298 if (h_method() != NULL) { 1299 JavaCallArguments args; // No arguments 1300 JavaValue result(T_VOID); 1301 JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args) 1302 } 1303 } 1304 1305 1306 void InstanceKlass::mask_for(const methodHandle& method, int bci, 1307 InterpreterOopMap* entry_for) { 1308 // Lazily create the _oop_map_cache at first request 1309 // Lock-free access requires load_acquire. 1310 OopMapCache* oop_map_cache = OrderAccess::load_acquire(&_oop_map_cache); 1311 if (oop_map_cache == NULL) { 1312 MutexLocker x(OopMapCacheAlloc_lock); 1313 // Check if _oop_map_cache was allocated while we were waiting for this lock 1314 if ((oop_map_cache = _oop_map_cache) == NULL) { 1315 oop_map_cache = new OopMapCache(); 1316 // Ensure _oop_map_cache is stable, since it is examined without a lock 1317 OrderAccess::release_store(&_oop_map_cache, oop_map_cache); 1318 } 1319 } 1320 // _oop_map_cache is constant after init; lookup below does its own locking. 1321 oop_map_cache->lookup(method, bci, entry_for); 1322 } 1323 1324 1325 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const { 1326 for (JavaFieldStream fs(this); !fs.done(); fs.next()) { 1327 Symbol* f_name = fs.name(); 1328 Symbol* f_sig = fs.signature(); 1329 if (f_name == name && f_sig == sig) { 1330 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index()); 1331 return true; 1332 } 1333 } 1334 return false; 1335 } 1336 1337 1338 Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const { 1339 const int n = local_interfaces()->length(); 1340 for (int i = 0; i < n; i++) { 1341 Klass* intf1 = local_interfaces()->at(i); 1342 assert(intf1->is_interface(), "just checking type"); 1343 // search for field in current interface 1344 if (InstanceKlass::cast(intf1)->find_local_field(name, sig, fd)) { 1345 assert(fd->is_static(), "interface field must be static"); 1346 return intf1; 1347 } 1348 // search for field in direct superinterfaces 1349 Klass* intf2 = InstanceKlass::cast(intf1)->find_interface_field(name, sig, fd); 1350 if (intf2 != NULL) return intf2; 1351 } 1352 // otherwise field lookup fails 1353 return NULL; 1354 } 1355 1356 1357 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const { 1358 // search order according to newest JVM spec (5.4.3.2, p.167). 1359 // 1) search for field in current klass 1360 if (find_local_field(name, sig, fd)) { 1361 return const_cast<InstanceKlass*>(this); 1362 } 1363 // 2) search for field recursively in direct superinterfaces 1364 { Klass* intf = find_interface_field(name, sig, fd); 1365 if (intf != NULL) return intf; 1366 } 1367 // 3) apply field lookup recursively if superclass exists 1368 { Klass* supr = super(); 1369 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, fd); 1370 } 1371 // 4) otherwise field lookup fails 1372 return NULL; 1373 } 1374 1375 1376 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const { 1377 // search order according to newest JVM spec (5.4.3.2, p.167). 1378 // 1) search for field in current klass 1379 if (find_local_field(name, sig, fd)) { 1380 if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this); 1381 } 1382 // 2) search for field recursively in direct superinterfaces 1383 if (is_static) { 1384 Klass* intf = find_interface_field(name, sig, fd); 1385 if (intf != NULL) return intf; 1386 } 1387 // 3) apply field lookup recursively if superclass exists 1388 { Klass* supr = super(); 1389 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, is_static, fd); 1390 } 1391 // 4) otherwise field lookup fails 1392 return NULL; 1393 } 1394 1395 1396 bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const { 1397 for (JavaFieldStream fs(this); !fs.done(); fs.next()) { 1398 if (fs.offset() == offset) { 1399 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index()); 1400 if (fd->is_static() == is_static) return true; 1401 } 1402 } 1403 return false; 1404 } 1405 1406 1407 bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const { 1408 Klass* klass = const_cast<InstanceKlass*>(this); 1409 while (klass != NULL) { 1410 if (InstanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) { 1411 return true; 1412 } 1413 klass = klass->super(); 1414 } 1415 return false; 1416 } 1417 1418 1419 void InstanceKlass::methods_do(void f(Method* method)) { 1420 // Methods aren't stable until they are loaded. This can be read outside 1421 // a lock through the ClassLoaderData for profiling 1422 if (!is_loaded()) { 1423 return; 1424 } 1425 1426 int len = methods()->length(); 1427 for (int index = 0; index < len; index++) { 1428 Method* m = methods()->at(index); 1429 assert(m->is_method(), "must be method"); 1430 f(m); 1431 } 1432 } 1433 1434 1435 void InstanceKlass::do_local_static_fields(FieldClosure* cl) { 1436 for (JavaFieldStream fs(this); !fs.done(); fs.next()) { 1437 if (fs.access_flags().is_static()) { 1438 fieldDescriptor& fd = fs.field_descriptor(); 1439 cl->do_field(&fd); 1440 } 1441 } 1442 } 1443 1444 1445 void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle mirror, TRAPS) { 1446 for (JavaFieldStream fs(this); !fs.done(); fs.next()) { 1447 if (fs.access_flags().is_static()) { 1448 fieldDescriptor& fd = fs.field_descriptor(); 1449 f(&fd, mirror, CHECK); 1450 } 1451 } 1452 } 1453 1454 1455 static int compare_fields_by_offset(int* a, int* b) { 1456 return a[0] - b[0]; 1457 } 1458 1459 void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) { 1460 InstanceKlass* super = superklass(); 1461 if (super != NULL) { 1462 super->do_nonstatic_fields(cl); 1463 } 1464 fieldDescriptor fd; 1465 int length = java_fields_count(); 1466 // In DebugInfo nonstatic fields are sorted by offset. 1467 int* fields_sorted = NEW_C_HEAP_ARRAY(int, 2*(length+1), mtClass); 1468 int j = 0; 1469 for (int i = 0; i < length; i += 1) { 1470 fd.reinitialize(this, i); 1471 if (!fd.is_static()) { 1472 fields_sorted[j + 0] = fd.offset(); 1473 fields_sorted[j + 1] = i; 1474 j += 2; 1475 } 1476 } 1477 if (j > 0) { 1478 length = j; 1479 // _sort_Fn is defined in growableArray.hpp. 1480 qsort(fields_sorted, length/2, 2*sizeof(int), (_sort_Fn)compare_fields_by_offset); 1481 for (int i = 0; i < length; i += 2) { 1482 fd.reinitialize(this, fields_sorted[i + 1]); 1483 assert(!fd.is_static() && fd.offset() == fields_sorted[i], "only nonstatic fields"); 1484 cl->do_field(&fd); 1485 } 1486 } 1487 FREE_C_HEAP_ARRAY(int, fields_sorted); 1488 } 1489 1490 1491 void InstanceKlass::array_klasses_do(void f(Klass* k, TRAPS), TRAPS) { 1492 if (array_klasses() != NULL) 1493 ArrayKlass::cast(array_klasses())->array_klasses_do(f, THREAD); 1494 } 1495 1496 void InstanceKlass::array_klasses_do(void f(Klass* k)) { 1497 if (array_klasses() != NULL) 1498 ArrayKlass::cast(array_klasses())->array_klasses_do(f); 1499 } 1500 1501 #ifdef ASSERT 1502 static int linear_search(const Array<Method*>* methods, 1503 const Symbol* name, 1504 const Symbol* signature) { 1505 const int len = methods->length(); 1506 for (int index = 0; index < len; index++) { 1507 const Method* const m = methods->at(index); 1508 assert(m->is_method(), "must be method"); 1509 if (m->signature() == signature && m->name() == name) { 1510 return index; 1511 } 1512 } 1513 return -1; 1514 } 1515 #endif 1516 1517 static int binary_search(const Array<Method*>* methods, const Symbol* name) { 1518 int len = methods->length(); 1519 // methods are sorted, so do binary search 1520 int l = 0; 1521 int h = len - 1; 1522 while (l <= h) { 1523 int mid = (l + h) >> 1; 1524 Method* m = methods->at(mid); 1525 assert(m->is_method(), "must be method"); 1526 int res = m->name()->fast_compare(name); 1527 if (res == 0) { 1528 return mid; 1529 } else if (res < 0) { 1530 l = mid + 1; 1531 } else { 1532 h = mid - 1; 1533 } 1534 } 1535 return -1; 1536 } 1537 1538 // find_method looks up the name/signature in the local methods array 1539 Method* InstanceKlass::find_method(const Symbol* name, 1540 const Symbol* signature) const { 1541 return find_method_impl(name, signature, find_overpass, find_static, find_private); 1542 } 1543 1544 Method* InstanceKlass::find_method_impl(const Symbol* name, 1545 const Symbol* signature, 1546 OverpassLookupMode overpass_mode, 1547 StaticLookupMode static_mode, 1548 PrivateLookupMode private_mode) const { 1549 return InstanceKlass::find_method_impl(methods(), 1550 name, 1551 signature, 1552 overpass_mode, 1553 static_mode, 1554 private_mode); 1555 } 1556 1557 // find_instance_method looks up the name/signature in the local methods array 1558 // and skips over static methods 1559 Method* InstanceKlass::find_instance_method(const Array<Method*>* methods, 1560 const Symbol* name, 1561 const Symbol* signature, 1562 PrivateLookupMode private_mode) { 1563 Method* const meth = InstanceKlass::find_method_impl(methods, 1564 name, 1565 signature, 1566 find_overpass, 1567 skip_static, 1568 private_mode); 1569 assert(((meth == NULL) || !meth->is_static()), 1570 "find_instance_method should have skipped statics"); 1571 return meth; 1572 } 1573 1574 // find_instance_method looks up the name/signature in the local methods array 1575 // and skips over static methods 1576 Method* InstanceKlass::find_instance_method(const Symbol* name, 1577 const Symbol* signature, 1578 PrivateLookupMode private_mode) const { 1579 return InstanceKlass::find_instance_method(methods(), name, signature, private_mode); 1580 } 1581 1582 // Find looks up the name/signature in the local methods array 1583 // and filters on the overpass, static and private flags 1584 // This returns the first one found 1585 // note that the local methods array can have up to one overpass, one static 1586 // and one instance (private or not) with the same name/signature 1587 Method* InstanceKlass::find_local_method(const Symbol* name, 1588 const Symbol* signature, 1589 OverpassLookupMode overpass_mode, 1590 StaticLookupMode static_mode, 1591 PrivateLookupMode private_mode) const { 1592 return InstanceKlass::find_method_impl(methods(), 1593 name, 1594 signature, 1595 overpass_mode, 1596 static_mode, 1597 private_mode); 1598 } 1599 1600 // Find looks up the name/signature in the local methods array 1601 // and filters on the overpass, static and private flags 1602 // This returns the first one found 1603 // note that the local methods array can have up to one overpass, one static 1604 // and one instance (private or not) with the same name/signature 1605 Method* InstanceKlass::find_local_method(const Array<Method*>* methods, 1606 const Symbol* name, 1607 const Symbol* signature, 1608 OverpassLookupMode overpass_mode, 1609 StaticLookupMode static_mode, 1610 PrivateLookupMode private_mode) { 1611 return InstanceKlass::find_method_impl(methods, 1612 name, 1613 signature, 1614 overpass_mode, 1615 static_mode, 1616 private_mode); 1617 } 1618 1619 Method* InstanceKlass::find_method(const Array<Method*>* methods, 1620 const Symbol* name, 1621 const Symbol* signature) { 1622 return InstanceKlass::find_method_impl(methods, 1623 name, 1624 signature, 1625 find_overpass, 1626 find_static, 1627 find_private); 1628 } 1629 1630 Method* InstanceKlass::find_method_impl(const Array<Method*>* methods, 1631 const Symbol* name, 1632 const Symbol* signature, 1633 OverpassLookupMode overpass_mode, 1634 StaticLookupMode static_mode, 1635 PrivateLookupMode private_mode) { 1636 int hit = find_method_index(methods, name, signature, overpass_mode, static_mode, private_mode); 1637 return hit >= 0 ? methods->at(hit): NULL; 1638 } 1639 1640 // true if method matches signature and conforms to skipping_X conditions. 1641 static bool method_matches(const Method* m, 1642 const Symbol* signature, 1643 bool skipping_overpass, 1644 bool skipping_static, 1645 bool skipping_private) { 1646 return ((m->signature() == signature) && 1647 (!skipping_overpass || !m->is_overpass()) && 1648 (!skipping_static || !m->is_static()) && 1649 (!skipping_private || !m->is_private())); 1650 } 1651 1652 // Used directly for default_methods to find the index into the 1653 // default_vtable_indices, and indirectly by find_method 1654 // find_method_index looks in the local methods array to return the index 1655 // of the matching name/signature. If, overpass methods are being ignored, 1656 // the search continues to find a potential non-overpass match. This capability 1657 // is important during method resolution to prefer a static method, for example, 1658 // over an overpass method. 1659 // There is the possibility in any _method's array to have the same name/signature 1660 // for a static method, an overpass method and a local instance method 1661 // To correctly catch a given method, the search criteria may need 1662 // to explicitly skip the other two. For local instance methods, it 1663 // is often necessary to skip private methods 1664 int InstanceKlass::find_method_index(const Array<Method*>* methods, 1665 const Symbol* name, 1666 const Symbol* signature, 1667 OverpassLookupMode overpass_mode, 1668 StaticLookupMode static_mode, 1669 PrivateLookupMode private_mode) { 1670 const bool skipping_overpass = (overpass_mode == skip_overpass); 1671 const bool skipping_static = (static_mode == skip_static); 1672 const bool skipping_private = (private_mode == skip_private); 1673 const int hit = binary_search(methods, name); 1674 if (hit != -1) { 1675 const Method* const m = methods->at(hit); 1676 1677 // Do linear search to find matching signature. First, quick check 1678 // for common case, ignoring overpasses if requested. 1679 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) { 1680 return hit; 1681 } 1682 1683 // search downwards through overloaded methods 1684 int i; 1685 for (i = hit - 1; i >= 0; --i) { 1686 const Method* const m = methods->at(i); 1687 assert(m->is_method(), "must be method"); 1688 if (m->name() != name) { 1689 break; 1690 } 1691 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) { 1692 return i; 1693 } 1694 } 1695 // search upwards 1696 for (i = hit + 1; i < methods->length(); ++i) { 1697 const Method* const m = methods->at(i); 1698 assert(m->is_method(), "must be method"); 1699 if (m->name() != name) { 1700 break; 1701 } 1702 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) { 1703 return i; 1704 } 1705 } 1706 // not found 1707 #ifdef ASSERT 1708 const int index = (skipping_overpass || skipping_static || skipping_private) ? -1 : 1709 linear_search(methods, name, signature); 1710 assert(-1 == index, "binary search should have found entry %d", index); 1711 #endif 1712 } 1713 return -1; 1714 } 1715 1716 int InstanceKlass::find_method_by_name(const Symbol* name, int* end) const { 1717 return find_method_by_name(methods(), name, end); 1718 } 1719 1720 int InstanceKlass::find_method_by_name(const Array<Method*>* methods, 1721 const Symbol* name, 1722 int* end_ptr) { 1723 assert(end_ptr != NULL, "just checking"); 1724 int start = binary_search(methods, name); 1725 int end = start + 1; 1726 if (start != -1) { 1727 while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start; 1728 while (end < methods->length() && (methods->at(end))->name() == name) ++end; 1729 *end_ptr = end; 1730 return start; 1731 } 1732 return -1; 1733 } 1734 1735 // uncached_lookup_method searches both the local class methods array and all 1736 // superclasses methods arrays, skipping any overpass methods in superclasses, 1737 // and possibly skipping private methods. 1738 Method* InstanceKlass::uncached_lookup_method(const Symbol* name, 1739 const Symbol* signature, 1740 OverpassLookupMode overpass_mode, 1741 PrivateLookupMode private_mode) const { 1742 OverpassLookupMode overpass_local_mode = overpass_mode; 1743 const Klass* klass = this; 1744 while (klass != NULL) { 1745 Method* const method = InstanceKlass::cast(klass)->find_method_impl(name, 1746 signature, 1747 overpass_local_mode, 1748 find_static, 1749 private_mode); 1750 if (method != NULL) { 1751 return method; 1752 } 1753 klass = klass->super(); 1754 overpass_local_mode = skip_overpass; // Always ignore overpass methods in superclasses 1755 } 1756 return NULL; 1757 } 1758 1759 #ifdef ASSERT 1760 // search through class hierarchy and return true if this class or 1761 // one of the superclasses was redefined 1762 bool InstanceKlass::has_redefined_this_or_super() const { 1763 const Klass* klass = this; 1764 while (klass != NULL) { 1765 if (InstanceKlass::cast(klass)->has_been_redefined()) { 1766 return true; 1767 } 1768 klass = klass->super(); 1769 } 1770 return false; 1771 } 1772 #endif 1773 1774 // lookup a method in the default methods list then in all transitive interfaces 1775 // Do NOT return private or static methods 1776 Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name, 1777 Symbol* signature) const { 1778 Method* m = NULL; 1779 if (default_methods() != NULL) { 1780 m = find_method(default_methods(), name, signature); 1781 } 1782 // Look up interfaces 1783 if (m == NULL) { 1784 m = lookup_method_in_all_interfaces(name, signature, find_defaults); 1785 } 1786 return m; 1787 } 1788 1789 // lookup a method in all the interfaces that this class implements 1790 // Do NOT return private or static methods, new in JDK8 which are not externally visible 1791 // They should only be found in the initial InterfaceMethodRef 1792 Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name, 1793 Symbol* signature, 1794 DefaultsLookupMode defaults_mode) const { 1795 Array<Klass*>* all_ifs = transitive_interfaces(); 1796 int num_ifs = all_ifs->length(); 1797 InstanceKlass *ik = NULL; 1798 for (int i = 0; i < num_ifs; i++) { 1799 ik = InstanceKlass::cast(all_ifs->at(i)); 1800 Method* m = ik->lookup_method(name, signature); 1801 if (m != NULL && m->is_public() && !m->is_static() && 1802 ((defaults_mode != skip_defaults) || !m->is_default_method())) { 1803 return m; 1804 } 1805 } 1806 return NULL; 1807 } 1808 1809 /* jni_id_for_impl for jfieldIds only */ 1810 JNIid* InstanceKlass::jni_id_for_impl(int offset) { 1811 MutexLocker ml(JfieldIdCreation_lock); 1812 // Retry lookup after we got the lock 1813 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset); 1814 if (probe == NULL) { 1815 // Slow case, allocate new static field identifier 1816 probe = new JNIid(this, offset, jni_ids()); 1817 set_jni_ids(probe); 1818 } 1819 return probe; 1820 } 1821 1822 1823 /* jni_id_for for jfieldIds only */ 1824 JNIid* InstanceKlass::jni_id_for(int offset) { 1825 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset); 1826 if (probe == NULL) { 1827 probe = jni_id_for_impl(offset); 1828 } 1829 return probe; 1830 } 1831 1832 u2 InstanceKlass::enclosing_method_data(int offset) const { 1833 const Array<jushort>* const inner_class_list = inner_classes(); 1834 if (inner_class_list == NULL) { 1835 return 0; 1836 } 1837 const int length = inner_class_list->length(); 1838 if (length % inner_class_next_offset == 0) { 1839 return 0; 1840 } 1841 const int index = length - enclosing_method_attribute_size; 1842 assert(offset < enclosing_method_attribute_size, "invalid offset"); 1843 return inner_class_list->at(index + offset); 1844 } 1845 1846 void InstanceKlass::set_enclosing_method_indices(u2 class_index, 1847 u2 method_index) { 1848 Array<jushort>* inner_class_list = inner_classes(); 1849 assert (inner_class_list != NULL, "_inner_classes list is not set up"); 1850 int length = inner_class_list->length(); 1851 if (length % inner_class_next_offset == enclosing_method_attribute_size) { 1852 int index = length - enclosing_method_attribute_size; 1853 inner_class_list->at_put( 1854 index + enclosing_method_class_index_offset, class_index); 1855 inner_class_list->at_put( 1856 index + enclosing_method_method_index_offset, method_index); 1857 } 1858 } 1859 1860 // Lookup or create a jmethodID. 1861 // This code is called by the VMThread and JavaThreads so the 1862 // locking has to be done very carefully to avoid deadlocks 1863 // and/or other cache consistency problems. 1864 // 1865 jmethodID InstanceKlass::get_jmethod_id(const methodHandle& method_h) { 1866 size_t idnum = (size_t)method_h->method_idnum(); 1867 jmethodID* jmeths = methods_jmethod_ids_acquire(); 1868 size_t length = 0; 1869 jmethodID id = NULL; 1870 1871 // We use a double-check locking idiom here because this cache is 1872 // performance sensitive. In the normal system, this cache only 1873 // transitions from NULL to non-NULL which is safe because we use 1874 // release_set_methods_jmethod_ids() to advertise the new cache. 1875 // A partially constructed cache should never be seen by a racing 1876 // thread. We also use release_store() to save a new jmethodID 1877 // in the cache so a partially constructed jmethodID should never be 1878 // seen either. Cache reads of existing jmethodIDs proceed without a 1879 // lock, but cache writes of a new jmethodID requires uniqueness and 1880 // creation of the cache itself requires no leaks so a lock is 1881 // generally acquired in those two cases. 1882 // 1883 // If the RedefineClasses() API has been used, then this cache can 1884 // grow and we'll have transitions from non-NULL to bigger non-NULL. 1885 // Cache creation requires no leaks and we require safety between all 1886 // cache accesses and freeing of the old cache so a lock is generally 1887 // acquired when the RedefineClasses() API has been used. 1888 1889 if (jmeths != NULL) { 1890 // the cache already exists 1891 if (!idnum_can_increment()) { 1892 // the cache can't grow so we can just get the current values 1893 get_jmethod_id_length_value(jmeths, idnum, &length, &id); 1894 } else { 1895 // cache can grow so we have to be more careful 1896 if (Threads::number_of_threads() == 0 || 1897 SafepointSynchronize::is_at_safepoint()) { 1898 // we're single threaded or at a safepoint - no locking needed 1899 get_jmethod_id_length_value(jmeths, idnum, &length, &id); 1900 } else { 1901 MutexLocker ml(JmethodIdCreation_lock); 1902 get_jmethod_id_length_value(jmeths, idnum, &length, &id); 1903 } 1904 } 1905 } 1906 // implied else: 1907 // we need to allocate a cache so default length and id values are good 1908 1909 if (jmeths == NULL || // no cache yet 1910 length <= idnum || // cache is too short 1911 id == NULL) { // cache doesn't contain entry 1912 1913 // This function can be called by the VMThread so we have to do all 1914 // things that might block on a safepoint before grabbing the lock. 1915 // Otherwise, we can deadlock with the VMThread or have a cache 1916 // consistency issue. These vars keep track of what we might have 1917 // to free after the lock is dropped. 1918 jmethodID to_dealloc_id = NULL; 1919 jmethodID* to_dealloc_jmeths = NULL; 1920 1921 // may not allocate new_jmeths or use it if we allocate it 1922 jmethodID* new_jmeths = NULL; 1923 if (length <= idnum) { 1924 // allocate a new cache that might be used 1925 size_t size = MAX2(idnum+1, (size_t)idnum_allocated_count()); 1926 new_jmeths = NEW_C_HEAP_ARRAY(jmethodID, size+1, mtClass); 1927 memset(new_jmeths, 0, (size+1)*sizeof(jmethodID)); 1928 // cache size is stored in element[0], other elements offset by one 1929 new_jmeths[0] = (jmethodID)size; 1930 } 1931 1932 // allocate a new jmethodID that might be used 1933 jmethodID new_id = NULL; 1934 if (method_h->is_old() && !method_h->is_obsolete()) { 1935 // The method passed in is old (but not obsolete), we need to use the current version 1936 Method* current_method = method_with_idnum((int)idnum); 1937 assert(current_method != NULL, "old and but not obsolete, so should exist"); 1938 new_id = Method::make_jmethod_id(class_loader_data(), current_method); 1939 } else { 1940 // It is the current version of the method or an obsolete method, 1941 // use the version passed in 1942 new_id = Method::make_jmethod_id(class_loader_data(), method_h()); 1943 } 1944 1945 if (Threads::number_of_threads() == 0 || 1946 SafepointSynchronize::is_at_safepoint()) { 1947 // we're single threaded or at a safepoint - no locking needed 1948 id = get_jmethod_id_fetch_or_update(idnum, new_id, new_jmeths, 1949 &to_dealloc_id, &to_dealloc_jmeths); 1950 } else { 1951 MutexLocker ml(JmethodIdCreation_lock); 1952 id = get_jmethod_id_fetch_or_update(idnum, new_id, new_jmeths, 1953 &to_dealloc_id, &to_dealloc_jmeths); 1954 } 1955 1956 // The lock has been dropped so we can free resources. 1957 // Free up either the old cache or the new cache if we allocated one. 1958 if (to_dealloc_jmeths != NULL) { 1959 FreeHeap(to_dealloc_jmeths); 1960 } 1961 // free up the new ID since it wasn't needed 1962 if (to_dealloc_id != NULL) { 1963 Method::destroy_jmethod_id(class_loader_data(), to_dealloc_id); 1964 } 1965 } 1966 return id; 1967 } 1968 1969 // Figure out how many jmethodIDs haven't been allocated, and make 1970 // sure space for them is pre-allocated. This makes getting all 1971 // method ids much, much faster with classes with more than 8 1972 // methods, and has a *substantial* effect on performance with jvmti 1973 // code that loads all jmethodIDs for all classes. 1974 void InstanceKlass::ensure_space_for_methodids(int start_offset) { 1975 int new_jmeths = 0; 1976 int length = methods()->length(); 1977 for (int index = start_offset; index < length; index++) { 1978 Method* m = methods()->at(index); 1979 jmethodID id = m->find_jmethod_id_or_null(); 1980 if (id == NULL) { 1981 new_jmeths++; 1982 } 1983 } 1984 if (new_jmeths != 0) { 1985 Method::ensure_jmethod_ids(class_loader_data(), new_jmeths); 1986 } 1987 } 1988 1989 // Common code to fetch the jmethodID from the cache or update the 1990 // cache with the new jmethodID. This function should never do anything 1991 // that causes the caller to go to a safepoint or we can deadlock with 1992 // the VMThread or have cache consistency issues. 1993 // 1994 jmethodID InstanceKlass::get_jmethod_id_fetch_or_update( 1995 size_t idnum, jmethodID new_id, 1996 jmethodID* new_jmeths, jmethodID* to_dealloc_id_p, 1997 jmethodID** to_dealloc_jmeths_p) { 1998 assert(new_id != NULL, "sanity check"); 1999 assert(to_dealloc_id_p != NULL, "sanity check"); 2000 assert(to_dealloc_jmeths_p != NULL, "sanity check"); 2001 assert(Threads::number_of_threads() == 0 || 2002 SafepointSynchronize::is_at_safepoint() || 2003 JmethodIdCreation_lock->owned_by_self(), "sanity check"); 2004 2005 // reacquire the cache - we are locked, single threaded or at a safepoint 2006 jmethodID* jmeths = methods_jmethod_ids_acquire(); 2007 jmethodID id = NULL; 2008 size_t length = 0; 2009 2010 if (jmeths == NULL || // no cache yet 2011 (length = (size_t)jmeths[0]) <= idnum) { // cache is too short 2012 if (jmeths != NULL) { 2013 // copy any existing entries from the old cache 2014 for (size_t index = 0; index < length; index++) { 2015 new_jmeths[index+1] = jmeths[index+1]; 2016 } 2017 *to_dealloc_jmeths_p = jmeths; // save old cache for later delete 2018 } 2019 release_set_methods_jmethod_ids(jmeths = new_jmeths); 2020 } else { 2021 // fetch jmethodID (if any) from the existing cache 2022 id = jmeths[idnum+1]; 2023 *to_dealloc_jmeths_p = new_jmeths; // save new cache for later delete 2024 } 2025 if (id == NULL) { 2026 // No matching jmethodID in the existing cache or we have a new 2027 // cache or we just grew the cache. This cache write is done here 2028 // by the first thread to win the foot race because a jmethodID 2029 // needs to be unique once it is generally available. 2030 id = new_id; 2031 2032 // The jmethodID cache can be read while unlocked so we have to 2033 // make sure the new jmethodID is complete before installing it 2034 // in the cache. 2035 OrderAccess::release_store(&jmeths[idnum+1], id); 2036 } else { 2037 *to_dealloc_id_p = new_id; // save new id for later delete 2038 } 2039 return id; 2040 } 2041 2042 2043 // Common code to get the jmethodID cache length and the jmethodID 2044 // value at index idnum if there is one. 2045 // 2046 void InstanceKlass::get_jmethod_id_length_value(jmethodID* cache, 2047 size_t idnum, size_t *length_p, jmethodID* id_p) { 2048 assert(cache != NULL, "sanity check"); 2049 assert(length_p != NULL, "sanity check"); 2050 assert(id_p != NULL, "sanity check"); 2051 2052 // cache size is stored in element[0], other elements offset by one 2053 *length_p = (size_t)cache[0]; 2054 if (*length_p <= idnum) { // cache is too short 2055 *id_p = NULL; 2056 } else { 2057 *id_p = cache[idnum+1]; // fetch jmethodID (if any) 2058 } 2059 } 2060 2061 2062 // Lookup a jmethodID, NULL if not found. Do no blocking, no allocations, no handles 2063 jmethodID InstanceKlass::jmethod_id_or_null(Method* method) { 2064 size_t idnum = (size_t)method->method_idnum(); 2065 jmethodID* jmeths = methods_jmethod_ids_acquire(); 2066 size_t length; // length assigned as debugging crumb 2067 jmethodID id = NULL; 2068 if (jmeths != NULL && // If there is a cache 2069 (length = (size_t)jmeths[0]) > idnum) { // and if it is long enough, 2070 id = jmeths[idnum+1]; // Look up the id (may be NULL) 2071 } 2072 return id; 2073 } 2074 2075 inline DependencyContext InstanceKlass::dependencies() { 2076 DependencyContext dep_context(&_dep_context); 2077 return dep_context; 2078 } 2079 2080 int InstanceKlass::mark_dependent_nmethods(KlassDepChange& changes) { 2081 return dependencies().mark_dependent_nmethods(changes); 2082 } 2083 2084 void InstanceKlass::add_dependent_nmethod(nmethod* nm) { 2085 dependencies().add_dependent_nmethod(nm); 2086 } 2087 2088 void InstanceKlass::remove_dependent_nmethod(nmethod* nm, bool delete_immediately) { 2089 dependencies().remove_dependent_nmethod(nm, delete_immediately); 2090 } 2091 2092 #ifndef PRODUCT 2093 void InstanceKlass::print_dependent_nmethods(bool verbose) { 2094 dependencies().print_dependent_nmethods(verbose); 2095 } 2096 2097 bool InstanceKlass::is_dependent_nmethod(nmethod* nm) { 2098 return dependencies().is_dependent_nmethod(nm); 2099 } 2100 #endif //PRODUCT 2101 2102 void InstanceKlass::clean_weak_instanceklass_links() { 2103 clean_implementors_list(); 2104 clean_method_data(); 2105 2106 // Since GC iterates InstanceKlasses sequentially, it is safe to remove stale entries here. 2107 DependencyContext dep_context(&_dep_context); 2108 dep_context.expunge_stale_entries(); 2109 } 2110 2111 void InstanceKlass::clean_implementors_list() { 2112 assert(is_loader_alive(), "this klass should be live"); 2113 if (is_interface()) { 2114 if (ClassUnloading) { 2115 Klass* impl = implementor(); 2116 if (impl != NULL) { 2117 if (!impl->is_loader_alive()) { 2118 // remove this guy 2119 Klass** klass = adr_implementor(); 2120 assert(klass != NULL, "null klass"); 2121 if (klass != NULL) { 2122 *klass = NULL; 2123 } 2124 } 2125 } 2126 } 2127 } 2128 } 2129 2130 void InstanceKlass::clean_method_data() { 2131 for (int m = 0; m < methods()->length(); m++) { 2132 MethodData* mdo = methods()->at(m)->method_data(); 2133 if (mdo != NULL) { 2134 mdo->clean_method_data(/*always_clean*/false); 2135 } 2136 } 2137 } 2138 2139 bool InstanceKlass::supers_have_passed_fingerprint_checks() { 2140 if (java_super() != NULL && !java_super()->has_passed_fingerprint_check()) { 2141 ResourceMark rm; 2142 log_trace(class, fingerprint)("%s : super %s not fingerprinted", external_name(), java_super()->external_name()); 2143 return false; 2144 } 2145 2146 Array<Klass*>* local_interfaces = this->local_interfaces(); 2147 if (local_interfaces != NULL) { 2148 int length = local_interfaces->length(); 2149 for (int i = 0; i < length; i++) { 2150 InstanceKlass* intf = InstanceKlass::cast(local_interfaces->at(i)); 2151 if (!intf->has_passed_fingerprint_check()) { 2152 ResourceMark rm; 2153 log_trace(class, fingerprint)("%s : interface %s not fingerprinted", external_name(), intf->external_name()); 2154 return false; 2155 } 2156 } 2157 } 2158 2159 return true; 2160 } 2161 2162 bool InstanceKlass::should_store_fingerprint(bool is_anonymous) { 2163 #if INCLUDE_AOT 2164 // We store the fingerprint into the InstanceKlass only in the following 2 cases: 2165 if (CalculateClassFingerprint) { 2166 // (1) We are running AOT to generate a shared library. 2167 return true; 2168 } 2169 if (DumpSharedSpaces) { 2170 // (2) We are running -Xshare:dump to create a shared archive 2171 return true; 2172 } 2173 if (UseAOT && is_anonymous) { 2174 // (3) We are using AOT code from a shared library and see an anonymous class 2175 return true; 2176 } 2177 #endif 2178 2179 // In all other cases we might set the _misc_has_passed_fingerprint_check bit, 2180 // but do not store the 64-bit fingerprint to save space. 2181 return false; 2182 } 2183 2184 bool InstanceKlass::has_stored_fingerprint() const { 2185 #if INCLUDE_AOT 2186 return should_store_fingerprint() || is_shared(); 2187 #else 2188 return false; 2189 #endif 2190 } 2191 2192 uint64_t InstanceKlass::get_stored_fingerprint() const { 2193 address adr = adr_fingerprint(); 2194 if (adr != NULL) { 2195 return (uint64_t)Bytes::get_native_u8(adr); // adr may not be 64-bit aligned 2196 } 2197 return 0; 2198 } 2199 2200 void InstanceKlass::store_fingerprint(uint64_t fingerprint) { 2201 address adr = adr_fingerprint(); 2202 if (adr != NULL) { 2203 Bytes::put_native_u8(adr, (u8)fingerprint); // adr may not be 64-bit aligned 2204 2205 ResourceMark rm; 2206 log_trace(class, fingerprint)("stored as " PTR64_FORMAT " for class %s", fingerprint, external_name()); 2207 } 2208 } 2209 2210 void InstanceKlass::metaspace_pointers_do(MetaspaceClosure* it) { 2211 Klass::metaspace_pointers_do(it); 2212 2213 if (log_is_enabled(Trace, cds)) { 2214 ResourceMark rm; 2215 log_trace(cds)("Iter(InstanceKlass): %p (%s)", this, external_name()); 2216 } 2217 2218 it->push(&_annotations); 2219 it->push((Klass**)&_array_klasses); 2220 it->push(&_constants); 2221 it->push(&_inner_classes); 2222 it->push(&_array_name); 2223 #if INCLUDE_JVMTI 2224 it->push(&_previous_versions); 2225 #endif 2226 it->push(&_methods); 2227 it->push(&_default_methods); 2228 it->push(&_local_interfaces); 2229 it->push(&_transitive_interfaces); 2230 it->push(&_method_ordering); 2231 it->push(&_default_vtable_indices); 2232 it->push(&_fields); 2233 2234 if (itable_length() > 0) { 2235 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable(); 2236 int method_table_offset_in_words = ioe->offset()/wordSize; 2237 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words()) 2238 / itableOffsetEntry::size(); 2239 2240 for (int i = 0; i < nof_interfaces; i ++, ioe ++) { 2241 if (ioe->interface_klass() != NULL) { 2242 it->push(ioe->interface_klass_addr()); 2243 itableMethodEntry* ime = ioe->first_method_entry(this); 2244 int n = klassItable::method_count_for_interface(ioe->interface_klass()); 2245 for (int index = 0; index < n; index ++) { 2246 it->push(ime[index].method_addr()); 2247 } 2248 } 2249 } 2250 } 2251 2252 it->push(&_nest_members); 2253 } 2254 2255 void InstanceKlass::remove_unshareable_info() { 2256 Klass::remove_unshareable_info(); 2257 2258 if (is_in_error_state()) { 2259 // Classes are attempted to link during dumping and may fail, 2260 // but these classes are still in the dictionary and class list in CLD. 2261 // Check in_error state first because in_error is > linked state, so 2262 // is_linked() is true. 2263 // If there's a linking error, there is nothing else to remove. 2264 return; 2265 } 2266 2267 // Unlink the class 2268 if (is_linked()) { 2269 unlink_class(); 2270 } 2271 init_implementor(); 2272 2273 constants()->remove_unshareable_info(); 2274 2275 for (int i = 0; i < methods()->length(); i++) { 2276 Method* m = methods()->at(i); 2277 m->remove_unshareable_info(); 2278 } 2279 2280 // do array classes also. 2281 if (array_klasses() != NULL) { 2282 array_klasses()->remove_unshareable_info(); 2283 } 2284 2285 // These are not allocated from metaspace, but they should should all be empty 2286 // during dump time, so we don't need to worry about them in InstanceKlass::iterate(). 2287 guarantee(_source_debug_extension == NULL, "must be"); 2288 guarantee(_dep_context == DependencyContext::EMPTY, "must be"); 2289 guarantee(_osr_nmethods_head == NULL, "must be"); 2290 2291 #if INCLUDE_JVMTI 2292 guarantee(_breakpoints == NULL, "must be"); 2293 guarantee(_previous_versions == NULL, "must be"); 2294 #endif 2295 2296 _init_thread = NULL; 2297 _methods_jmethod_ids = NULL; 2298 _jni_ids = NULL; 2299 _oop_map_cache = NULL; 2300 // clear _nest_host to ensure re-load at runtime 2301 _nest_host = NULL; 2302 } 2303 2304 void InstanceKlass::remove_java_mirror() { 2305 Klass::remove_java_mirror(); 2306 2307 // do array classes also. 2308 if (array_klasses() != NULL) { 2309 array_klasses()->remove_java_mirror(); 2310 } 2311 } 2312 2313 void InstanceKlass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain, TRAPS) { 2314 set_package(loader_data, CHECK); 2315 Klass::restore_unshareable_info(loader_data, protection_domain, CHECK); 2316 2317 Array<Method*>* methods = this->methods(); 2318 int num_methods = methods->length(); 2319 for (int index2 = 0; index2 < num_methods; ++index2) { 2320 methodHandle m(THREAD, methods->at(index2)); 2321 m->restore_unshareable_info(CHECK); 2322 } 2323 if (JvmtiExport::has_redefined_a_class()) { 2324 // Reinitialize vtable because RedefineClasses may have changed some 2325 // entries in this vtable for super classes so the CDS vtable might 2326 // point to old or obsolete entries. RedefineClasses doesn't fix up 2327 // vtables in the shared system dictionary, only the main one. 2328 // It also redefines the itable too so fix that too. 2329 ResourceMark rm(THREAD); 2330 vtable().initialize_vtable(false, CHECK); 2331 itable().initialize_itable(false, CHECK); 2332 } 2333 2334 // restore constant pool resolved references 2335 constants()->restore_unshareable_info(CHECK); 2336 2337 if (array_klasses() != NULL) { 2338 // Array classes have null protection domain. 2339 // --> see ArrayKlass::complete_create_array_klass() 2340 array_klasses()->restore_unshareable_info(ClassLoaderData::the_null_class_loader_data(), Handle(), CHECK); 2341 } 2342 } 2343 2344 // returns true IFF is_in_error_state() has been changed as a result of this call. 2345 bool InstanceKlass::check_sharing_error_state() { 2346 assert(DumpSharedSpaces, "should only be called during dumping"); 2347 bool old_state = is_in_error_state(); 2348 2349 if (!is_in_error_state()) { 2350 bool bad = false; 2351 for (InstanceKlass* sup = java_super(); sup; sup = sup->java_super()) { 2352 if (sup->is_in_error_state()) { 2353 bad = true; 2354 break; 2355 } 2356 } 2357 if (!bad) { 2358 Array<Klass*>* interfaces = transitive_interfaces(); 2359 for (int i = 0; i < interfaces->length(); i++) { 2360 Klass* iface = interfaces->at(i); 2361 if (InstanceKlass::cast(iface)->is_in_error_state()) { 2362 bad = true; 2363 break; 2364 } 2365 } 2366 } 2367 2368 if (bad) { 2369 set_in_error_state(); 2370 } 2371 } 2372 2373 return (old_state != is_in_error_state()); 2374 } 2375 2376 #if INCLUDE_JVMTI 2377 static void clear_all_breakpoints(Method* m) { 2378 m->clear_all_breakpoints(); 2379 } 2380 #endif 2381 2382 void InstanceKlass::notify_unload_class(InstanceKlass* ik) { 2383 // notify the debugger 2384 if (JvmtiExport::should_post_class_unload()) { 2385 JvmtiExport::post_class_unload(ik); 2386 } 2387 2388 // notify ClassLoadingService of class unload 2389 ClassLoadingService::notify_class_unloaded(ik); 2390 } 2391 2392 void InstanceKlass::release_C_heap_structures(InstanceKlass* ik) { 2393 // Clean up C heap 2394 ik->release_C_heap_structures(); 2395 ik->constants()->release_C_heap_structures(); 2396 } 2397 2398 void InstanceKlass::release_C_heap_structures() { 2399 // Can't release the constant pool here because the constant pool can be 2400 // deallocated separately from the InstanceKlass for default methods and 2401 // redefine classes. 2402 2403 // Deallocate oop map cache 2404 if (_oop_map_cache != NULL) { 2405 delete _oop_map_cache; 2406 _oop_map_cache = NULL; 2407 } 2408 2409 // Deallocate JNI identifiers for jfieldIDs 2410 JNIid::deallocate(jni_ids()); 2411 set_jni_ids(NULL); 2412 2413 jmethodID* jmeths = methods_jmethod_ids_acquire(); 2414 if (jmeths != (jmethodID*)NULL) { 2415 release_set_methods_jmethod_ids(NULL); 2416 FreeHeap(jmeths); 2417 } 2418 2419 // Release dependencies. 2420 // It is desirable to use DC::remove_all_dependents() here, but, unfortunately, 2421 // it is not safe (see JDK-8143408). The problem is that the klass dependency 2422 // context can contain live dependencies, since there's a race between nmethod & 2423 // klass unloading. If the klass is dead when nmethod unloading happens, relevant 2424 // dependencies aren't removed from the context associated with the class (see 2425 // nmethod::flush_dependencies). It ends up during klass unloading as seemingly 2426 // live dependencies pointing to unloaded nmethods and causes a crash in 2427 // DC::remove_all_dependents() when it touches unloaded nmethod. 2428 dependencies().wipe(); 2429 2430 #if INCLUDE_JVMTI 2431 // Deallocate breakpoint records 2432 if (breakpoints() != 0x0) { 2433 methods_do(clear_all_breakpoints); 2434 assert(breakpoints() == 0x0, "should have cleared breakpoints"); 2435 } 2436 2437 // deallocate the cached class file 2438 if (_cached_class_file != NULL && !MetaspaceShared::is_in_shared_metaspace(_cached_class_file)) { 2439 os::free(_cached_class_file); 2440 _cached_class_file = NULL; 2441 } 2442 #endif 2443 2444 // Decrement symbol reference counts associated with the unloaded class. 2445 if (_name != NULL) _name->decrement_refcount(); 2446 // unreference array name derived from this class name (arrays of an unloaded 2447 // class can't be referenced anymore). 2448 if (_array_name != NULL) _array_name->decrement_refcount(); 2449 if (_source_debug_extension != NULL) FREE_C_HEAP_ARRAY(char, _source_debug_extension); 2450 } 2451 2452 void InstanceKlass::set_source_debug_extension(const char* array, int length) { 2453 if (array == NULL) { 2454 _source_debug_extension = NULL; 2455 } else { 2456 // Adding one to the attribute length in order to store a null terminator 2457 // character could cause an overflow because the attribute length is 2458 // already coded with an u4 in the classfile, but in practice, it's 2459 // unlikely to happen. 2460 assert((length+1) > length, "Overflow checking"); 2461 char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass); 2462 for (int i = 0; i < length; i++) { 2463 sde[i] = array[i]; 2464 } 2465 sde[length] = '\0'; 2466 _source_debug_extension = sde; 2467 } 2468 } 2469 2470 const char* InstanceKlass::signature_name() const { 2471 int hash_len = 0; 2472 char hash_buf[40]; 2473 2474 // If this is an anonymous class, append a hash to make the name unique 2475 if (is_anonymous()) { 2476 intptr_t hash = (java_mirror() != NULL) ? java_mirror()->identity_hash() : 0; 2477 jio_snprintf(hash_buf, sizeof(hash_buf), "/" UINTX_FORMAT, (uintx)hash); 2478 hash_len = (int)strlen(hash_buf); 2479 } 2480 2481 // Get the internal name as a c string 2482 const char* src = (const char*) (name()->as_C_string()); 2483 const int src_length = (int)strlen(src); 2484 2485 char* dest = NEW_RESOURCE_ARRAY(char, src_length + hash_len + 3); 2486 2487 // Add L as type indicator 2488 int dest_index = 0; 2489 dest[dest_index++] = 'L'; 2490 2491 // Add the actual class name 2492 for (int src_index = 0; src_index < src_length; ) { 2493 dest[dest_index++] = src[src_index++]; 2494 } 2495 2496 // If we have a hash, append it 2497 for (int hash_index = 0; hash_index < hash_len; ) { 2498 dest[dest_index++] = hash_buf[hash_index++]; 2499 } 2500 2501 // Add the semicolon and the NULL 2502 dest[dest_index++] = ';'; 2503 dest[dest_index] = '\0'; 2504 return dest; 2505 } 2506 2507 // Used to obtain the package name from a fully qualified class name. 2508 Symbol* InstanceKlass::package_from_name(const Symbol* name, TRAPS) { 2509 if (name == NULL) { 2510 return NULL; 2511 } else { 2512 if (name->utf8_length() <= 0) { 2513 return NULL; 2514 } 2515 ResourceMark rm; 2516 const char* package_name = ClassLoader::package_from_name((const char*) name->as_C_string()); 2517 if (package_name == NULL) { 2518 return NULL; 2519 } 2520 Symbol* pkg_name = SymbolTable::new_symbol(package_name, THREAD); 2521 return pkg_name; 2522 } 2523 } 2524 2525 ModuleEntry* InstanceKlass::module() const { 2526 if (!in_unnamed_package()) { 2527 return _package_entry->module(); 2528 } 2529 const Klass* host = host_klass(); 2530 if (host == NULL) { 2531 return class_loader_data()->unnamed_module(); 2532 } 2533 return host->class_loader_data()->unnamed_module(); 2534 } 2535 2536 void InstanceKlass::set_package(ClassLoaderData* loader_data, TRAPS) { 2537 2538 // ensure java/ packages only loaded by boot or platform builtin loaders 2539 Handle class_loader(THREAD, loader_data->class_loader()); 2540 check_prohibited_package(name(), class_loader, CHECK); 2541 2542 TempNewSymbol pkg_name = package_from_name(name(), CHECK); 2543 2544 if (pkg_name != NULL && loader_data != NULL) { 2545 2546 // Find in class loader's package entry table. 2547 _package_entry = loader_data->packages()->lookup_only(pkg_name); 2548 2549 // If the package name is not found in the loader's package 2550 // entry table, it is an indication that the package has not 2551 // been defined. Consider it defined within the unnamed module. 2552 if (_package_entry == NULL) { 2553 ResourceMark rm; 2554 2555 if (!ModuleEntryTable::javabase_defined()) { 2556 // Before java.base is defined during bootstrapping, define all packages in 2557 // the java.base module. If a non-java.base package is erroneously placed 2558 // in the java.base module it will be caught later when java.base 2559 // is defined by ModuleEntryTable::verify_javabase_packages check. 2560 assert(ModuleEntryTable::javabase_moduleEntry() != NULL, JAVA_BASE_NAME " module is NULL"); 2561 _package_entry = loader_data->packages()->lookup(pkg_name, ModuleEntryTable::javabase_moduleEntry()); 2562 } else { 2563 assert(loader_data->unnamed_module() != NULL, "unnamed module is NULL"); 2564 _package_entry = loader_data->packages()->lookup(pkg_name, 2565 loader_data->unnamed_module()); 2566 } 2567 2568 // A package should have been successfully created 2569 assert(_package_entry != NULL, "Package entry for class %s not found, loader %s", 2570 name()->as_C_string(), loader_data->loader_name()); 2571 } 2572 2573 if (log_is_enabled(Debug, module)) { 2574 ResourceMark rm; 2575 ModuleEntry* m = _package_entry->module(); 2576 log_trace(module)("Setting package: class: %s, package: %s, loader: %s, module: %s", 2577 external_name(), 2578 pkg_name->as_C_string(), 2579 loader_data->loader_name(), 2580 (m->is_named() ? m->name()->as_C_string() : UNNAMED_MODULE)); 2581 } 2582 } else { 2583 ResourceMark rm; 2584 log_trace(module)("Setting package: class: %s, package: unnamed, loader: %s, module: %s", 2585 external_name(), 2586 (loader_data != NULL) ? loader_data->loader_name() : "NULL", 2587 UNNAMED_MODULE); 2588 } 2589 } 2590 2591 2592 // different versions of is_same_class_package 2593 2594 bool InstanceKlass::is_same_class_package(const Klass* class2) const { 2595 oop classloader1 = this->class_loader(); 2596 PackageEntry* classpkg1 = this->package(); 2597 if (class2->is_objArray_klass()) { 2598 class2 = ObjArrayKlass::cast(class2)->bottom_klass(); 2599 } 2600 2601 oop classloader2; 2602 PackageEntry* classpkg2; 2603 if (class2->is_instance_klass()) { 2604 classloader2 = class2->class_loader(); 2605 classpkg2 = class2->package(); 2606 } else { 2607 assert(class2->is_typeArray_klass(), "should be type array"); 2608 classloader2 = NULL; 2609 classpkg2 = NULL; 2610 } 2611 2612 // Same package is determined by comparing class loader 2613 // and package entries. Both must be the same. This rule 2614 // applies even to classes that are defined in the unnamed 2615 // package, they still must have the same class loader. 2616 if (oopDesc::equals(classloader1, classloader2) && (classpkg1 == classpkg2)) { 2617 return true; 2618 } 2619 2620 return false; 2621 } 2622 2623 // return true if this class and other_class are in the same package. Classloader 2624 // and classname information is enough to determine a class's package 2625 bool InstanceKlass::is_same_class_package(oop other_class_loader, 2626 const Symbol* other_class_name) const { 2627 if (!oopDesc::equals(class_loader(), other_class_loader)) { 2628 return false; 2629 } 2630 if (name()->fast_compare(other_class_name) == 0) { 2631 return true; 2632 } 2633 2634 { 2635 ResourceMark rm; 2636 2637 bool bad_class_name = false; 2638 const char* other_pkg = 2639 ClassLoader::package_from_name((const char*) other_class_name->as_C_string(), &bad_class_name); 2640 if (bad_class_name) { 2641 return false; 2642 } 2643 // Check that package_from_name() returns NULL, not "", if there is no package. 2644 assert(other_pkg == NULL || strlen(other_pkg) > 0, "package name is empty string"); 2645 2646 const Symbol* const this_package_name = 2647 this->package() != NULL ? this->package()->name() : NULL; 2648 2649 if (this_package_name == NULL || other_pkg == NULL) { 2650 // One of the two doesn't have a package. Only return true if the other 2651 // one also doesn't have a package. 2652 return (const char*)this_package_name == other_pkg; 2653 } 2654 2655 // Check if package is identical 2656 return this_package_name->equals(other_pkg); 2657 } 2658 } 2659 2660 // Returns true iff super_method can be overridden by a method in targetclassname 2661 // See JLS 3rd edition 8.4.6.1 2662 // Assumes name-signature match 2663 // "this" is InstanceKlass of super_method which must exist 2664 // note that the InstanceKlass of the method in the targetclassname has not always been created yet 2665 bool InstanceKlass::is_override(const methodHandle& super_method, Handle targetclassloader, Symbol* targetclassname, TRAPS) { 2666 // Private methods can not be overridden 2667 if (super_method->is_private()) { 2668 return false; 2669 } 2670 // If super method is accessible, then override 2671 if ((super_method->is_protected()) || 2672 (super_method->is_public())) { 2673 return true; 2674 } 2675 // Package-private methods are not inherited outside of package 2676 assert(super_method->is_package_private(), "must be package private"); 2677 return(is_same_class_package(targetclassloader(), targetclassname)); 2678 } 2679 2680 // Only boot and platform class loaders can define classes in "java/" packages. 2681 void InstanceKlass::check_prohibited_package(Symbol* class_name, 2682 Handle class_loader, 2683 TRAPS) { 2684 if (!class_loader.is_null() && 2685 !SystemDictionary::is_platform_class_loader(class_loader()) && 2686 class_name != NULL) { 2687 ResourceMark rm(THREAD); 2688 char* name = class_name->as_C_string(); 2689 if (strncmp(name, JAVAPKG, JAVAPKG_LEN) == 0 && name[JAVAPKG_LEN] == '/') { 2690 TempNewSymbol pkg_name = InstanceKlass::package_from_name(class_name, CHECK); 2691 assert(pkg_name != NULL, "Error in parsing package name starting with 'java/'"); 2692 name = pkg_name->as_C_string(); 2693 const char* class_loader_name = SystemDictionary::loader_name(class_loader()); 2694 StringUtils::replace_no_expand(name, "/", "."); 2695 const char* msg_text1 = "Class loader (instance of): "; 2696 const char* msg_text2 = " tried to load prohibited package name: "; 2697 size_t len = strlen(msg_text1) + strlen(class_loader_name) + strlen(msg_text2) + strlen(name) + 1; 2698 char* message = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, len); 2699 jio_snprintf(message, len, "%s%s%s%s", msg_text1, class_loader_name, msg_text2, name); 2700 THROW_MSG(vmSymbols::java_lang_SecurityException(), message); 2701 } 2702 } 2703 return; 2704 } 2705 2706 // tell if two classes have the same enclosing class (at package level) 2707 bool InstanceKlass::is_same_package_member(const Klass* class2, TRAPS) const { 2708 if (class2 == this) return true; 2709 if (!class2->is_instance_klass()) return false; 2710 2711 // must be in same package before we try anything else 2712 if (!is_same_class_package(class2)) 2713 return false; 2714 2715 // As long as there is an outer_this.getEnclosingClass, 2716 // shift the search outward. 2717 const InstanceKlass* outer_this = this; 2718 for (;;) { 2719 // As we walk along, look for equalities between outer_this and class2. 2720 // Eventually, the walks will terminate as outer_this stops 2721 // at the top-level class around the original class. 2722 bool ignore_inner_is_member; 2723 const Klass* next = outer_this->compute_enclosing_class(&ignore_inner_is_member, 2724 CHECK_false); 2725 if (next == NULL) break; 2726 if (next == class2) return true; 2727 outer_this = InstanceKlass::cast(next); 2728 } 2729 2730 // Now do the same for class2. 2731 const InstanceKlass* outer2 = InstanceKlass::cast(class2); 2732 for (;;) { 2733 bool ignore_inner_is_member; 2734 Klass* next = outer2->compute_enclosing_class(&ignore_inner_is_member, 2735 CHECK_false); 2736 if (next == NULL) break; 2737 // Might as well check the new outer against all available values. 2738 if (next == this) return true; 2739 if (next == outer_this) return true; 2740 outer2 = InstanceKlass::cast(next); 2741 } 2742 2743 // If by this point we have not found an equality between the 2744 // two classes, we know they are in separate package members. 2745 return false; 2746 } 2747 2748 bool InstanceKlass::find_inner_classes_attr(int* ooff, int* noff, TRAPS) const { 2749 constantPoolHandle i_cp(THREAD, constants()); 2750 for (InnerClassesIterator iter(this); !iter.done(); iter.next()) { 2751 int ioff = iter.inner_class_info_index(); 2752 if (ioff != 0) { 2753 // Check to see if the name matches the class we're looking for 2754 // before attempting to find the class. 2755 if (i_cp->klass_name_at_matches(this, ioff)) { 2756 Klass* inner_klass = i_cp->klass_at(ioff, CHECK_false); 2757 if (this == inner_klass) { 2758 *ooff = iter.outer_class_info_index(); 2759 *noff = iter.inner_name_index(); 2760 return true; 2761 } 2762 } 2763 } 2764 } 2765 return false; 2766 } 2767 2768 InstanceKlass* InstanceKlass::compute_enclosing_class(bool* inner_is_member, TRAPS) const { 2769 InstanceKlass* outer_klass = NULL; 2770 *inner_is_member = false; 2771 int ooff = 0, noff = 0; 2772 bool has_inner_classes_attr = find_inner_classes_attr(&ooff, &noff, THREAD); 2773 if (has_inner_classes_attr) { 2774 constantPoolHandle i_cp(THREAD, constants()); 2775 if (ooff != 0) { 2776 Klass* ok = i_cp->klass_at(ooff, CHECK_NULL); 2777 outer_klass = InstanceKlass::cast(ok); 2778 *inner_is_member = true; 2779 } 2780 if (NULL == outer_klass) { 2781 // It may be anonymous; try for that. 2782 int encl_method_class_idx = enclosing_method_class_index(); 2783 if (encl_method_class_idx != 0) { 2784 Klass* ok = i_cp->klass_at(encl_method_class_idx, CHECK_NULL); 2785 outer_klass = InstanceKlass::cast(ok); 2786 *inner_is_member = false; 2787 } 2788 } 2789 } 2790 2791 // If no inner class attribute found for this class. 2792 if (NULL == outer_klass) return NULL; 2793 2794 // Throws an exception if outer klass has not declared k as an inner klass 2795 // We need evidence that each klass knows about the other, or else 2796 // the system could allow a spoof of an inner class to gain access rights. 2797 Reflection::check_for_inner_class(outer_klass, this, *inner_is_member, CHECK_NULL); 2798 return outer_klass; 2799 } 2800 2801 jint InstanceKlass::compute_modifier_flags(TRAPS) const { 2802 jint access = access_flags().as_int(); 2803 2804 // But check if it happens to be member class. 2805 InnerClassesIterator iter(this); 2806 for (; !iter.done(); iter.next()) { 2807 int ioff = iter.inner_class_info_index(); 2808 // Inner class attribute can be zero, skip it. 2809 // Strange but true: JVM spec. allows null inner class refs. 2810 if (ioff == 0) continue; 2811 2812 // only look at classes that are already loaded 2813 // since we are looking for the flags for our self. 2814 Symbol* inner_name = constants()->klass_name_at(ioff); 2815 if (name() == inner_name) { 2816 // This is really a member class. 2817 access = iter.inner_access_flags(); 2818 break; 2819 } 2820 } 2821 // Remember to strip ACC_SUPER bit 2822 return (access & (~JVM_ACC_SUPER)) & JVM_ACC_WRITTEN_FLAGS; 2823 } 2824 2825 jint InstanceKlass::jvmti_class_status() const { 2826 jint result = 0; 2827 2828 if (is_linked()) { 2829 result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED; 2830 } 2831 2832 if (is_initialized()) { 2833 assert(is_linked(), "Class status is not consistent"); 2834 result |= JVMTI_CLASS_STATUS_INITIALIZED; 2835 } 2836 if (is_in_error_state()) { 2837 result |= JVMTI_CLASS_STATUS_ERROR; 2838 } 2839 return result; 2840 } 2841 2842 Method* InstanceKlass::method_at_itable(Klass* holder, int index, TRAPS) { 2843 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable(); 2844 int method_table_offset_in_words = ioe->offset()/wordSize; 2845 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words()) 2846 / itableOffsetEntry::size(); 2847 2848 for (int cnt = 0 ; ; cnt ++, ioe ++) { 2849 // If the interface isn't implemented by the receiver class, 2850 // the VM should throw IncompatibleClassChangeError. 2851 if (cnt >= nof_interfaces) { 2852 THROW_NULL(vmSymbols::java_lang_IncompatibleClassChangeError()); 2853 } 2854 2855 Klass* ik = ioe->interface_klass(); 2856 if (ik == holder) break; 2857 } 2858 2859 itableMethodEntry* ime = ioe->first_method_entry(this); 2860 Method* m = ime[index].method(); 2861 if (m == NULL) { 2862 THROW_NULL(vmSymbols::java_lang_AbstractMethodError()); 2863 } 2864 return m; 2865 } 2866 2867 2868 #if INCLUDE_JVMTI 2869 // update default_methods for redefineclasses for methods that are 2870 // not yet in the vtable due to concurrent subclass define and superinterface 2871 // redefinition 2872 // Note: those in the vtable, should have been updated via adjust_method_entries 2873 void InstanceKlass::adjust_default_methods(InstanceKlass* holder, bool* trace_name_printed) { 2874 // search the default_methods for uses of either obsolete or EMCP methods 2875 if (default_methods() != NULL) { 2876 for (int index = 0; index < default_methods()->length(); index ++) { 2877 Method* old_method = default_methods()->at(index); 2878 if (old_method == NULL || old_method->method_holder() != holder || !old_method->is_old()) { 2879 continue; // skip uninteresting entries 2880 } 2881 assert(!old_method->is_deleted(), "default methods may not be deleted"); 2882 2883 Method* new_method = holder->method_with_idnum(old_method->orig_method_idnum()); 2884 2885 assert(new_method != NULL, "method_with_idnum() should not be NULL"); 2886 assert(old_method != new_method, "sanity check"); 2887 2888 default_methods()->at_put(index, new_method); 2889 if (log_is_enabled(Info, redefine, class, update)) { 2890 ResourceMark rm; 2891 if (!(*trace_name_printed)) { 2892 log_info(redefine, class, update) 2893 ("adjust: klassname=%s default methods from name=%s", 2894 external_name(), old_method->method_holder()->external_name()); 2895 *trace_name_printed = true; 2896 } 2897 log_debug(redefine, class, update, vtables) 2898 ("default method update: %s(%s) ", 2899 new_method->name()->as_C_string(), new_method->signature()->as_C_string()); 2900 } 2901 } 2902 } 2903 } 2904 #endif // INCLUDE_JVMTI 2905 2906 // On-stack replacement stuff 2907 void InstanceKlass::add_osr_nmethod(nmethod* n) { 2908 // only one compilation can be active 2909 { 2910 // This is a short non-blocking critical region, so the no safepoint check is ok. 2911 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag); 2912 assert(n->is_osr_method(), "wrong kind of nmethod"); 2913 n->set_osr_link(osr_nmethods_head()); 2914 set_osr_nmethods_head(n); 2915 // Raise the highest osr level if necessary 2916 if (TieredCompilation) { 2917 Method* m = n->method(); 2918 m->set_highest_osr_comp_level(MAX2(m->highest_osr_comp_level(), n->comp_level())); 2919 } 2920 } 2921 2922 // Get rid of the osr methods for the same bci that have lower levels. 2923 if (TieredCompilation) { 2924 for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) { 2925 nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true); 2926 if (inv != NULL && inv->is_in_use()) { 2927 inv->make_not_entrant(); 2928 } 2929 } 2930 } 2931 } 2932 2933 // Remove osr nmethod from the list. Return true if found and removed. 2934 bool InstanceKlass::remove_osr_nmethod(nmethod* n) { 2935 // This is a short non-blocking critical region, so the no safepoint check is ok. 2936 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag); 2937 assert(n->is_osr_method(), "wrong kind of nmethod"); 2938 nmethod* last = NULL; 2939 nmethod* cur = osr_nmethods_head(); 2940 int max_level = CompLevel_none; // Find the max comp level excluding n 2941 Method* m = n->method(); 2942 // Search for match 2943 bool found = false; 2944 while(cur != NULL && cur != n) { 2945 if (TieredCompilation && m == cur->method()) { 2946 // Find max level before n 2947 max_level = MAX2(max_level, cur->comp_level()); 2948 } 2949 last = cur; 2950 cur = cur->osr_link(); 2951 } 2952 nmethod* next = NULL; 2953 if (cur == n) { 2954 found = true; 2955 next = cur->osr_link(); 2956 if (last == NULL) { 2957 // Remove first element 2958 set_osr_nmethods_head(next); 2959 } else { 2960 last->set_osr_link(next); 2961 } 2962 } 2963 n->set_osr_link(NULL); 2964 if (TieredCompilation) { 2965 cur = next; 2966 while (cur != NULL) { 2967 // Find max level after n 2968 if (m == cur->method()) { 2969 max_level = MAX2(max_level, cur->comp_level()); 2970 } 2971 cur = cur->osr_link(); 2972 } 2973 m->set_highest_osr_comp_level(max_level); 2974 } 2975 return found; 2976 } 2977 2978 int InstanceKlass::mark_osr_nmethods(const Method* m) { 2979 // This is a short non-blocking critical region, so the no safepoint check is ok. 2980 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag); 2981 nmethod* osr = osr_nmethods_head(); 2982 int found = 0; 2983 while (osr != NULL) { 2984 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain"); 2985 if (osr->method() == m) { 2986 osr->mark_for_deoptimization(); 2987 found++; 2988 } 2989 osr = osr->osr_link(); 2990 } 2991 return found; 2992 } 2993 2994 nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const { 2995 // This is a short non-blocking critical region, so the no safepoint check is ok. 2996 MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag); 2997 nmethod* osr = osr_nmethods_head(); 2998 nmethod* best = NULL; 2999 while (osr != NULL) { 3000 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain"); 3001 // There can be a time when a c1 osr method exists but we are waiting 3002 // for a c2 version. When c2 completes its osr nmethod we will trash 3003 // the c1 version and only be able to find the c2 version. However 3004 // while we overflow in the c1 code at back branches we don't want to 3005 // try and switch to the same code as we are already running 3006 3007 if (osr->method() == m && 3008 (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) { 3009 if (match_level) { 3010 if (osr->comp_level() == comp_level) { 3011 // Found a match - return it. 3012 return osr; 3013 } 3014 } else { 3015 if (best == NULL || (osr->comp_level() > best->comp_level())) { 3016 if (osr->comp_level() == CompLevel_highest_tier) { 3017 // Found the best possible - return it. 3018 return osr; 3019 } 3020 best = osr; 3021 } 3022 } 3023 } 3024 osr = osr->osr_link(); 3025 } 3026 if (best != NULL && best->comp_level() >= comp_level && match_level == false) { 3027 return best; 3028 } 3029 return NULL; 3030 } 3031 3032 // ----------------------------------------------------------------------------------------------------- 3033 // Printing 3034 3035 #ifndef PRODUCT 3036 3037 #define BULLET " - " 3038 3039 static const char* state_names[] = { 3040 "allocated", "loaded", "linked", "being_initialized", "fully_initialized", "initialization_error" 3041 }; 3042 3043 static void print_vtable(intptr_t* start, int len, outputStream* st) { 3044 for (int i = 0; i < len; i++) { 3045 intptr_t e = start[i]; 3046 st->print("%d : " INTPTR_FORMAT, i, e); 3047 if (e != 0 && ((Metadata*)e)->is_metaspace_object()) { 3048 st->print(" "); 3049 ((Metadata*)e)->print_value_on(st); 3050 } 3051 st->cr(); 3052 } 3053 } 3054 3055 static void print_vtable(vtableEntry* start, int len, outputStream* st) { 3056 return print_vtable(reinterpret_cast<intptr_t*>(start), len, st); 3057 } 3058 3059 void InstanceKlass::print_on(outputStream* st) const { 3060 assert(is_klass(), "must be klass"); 3061 Klass::print_on(st); 3062 3063 st->print(BULLET"instance size: %d", size_helper()); st->cr(); 3064 st->print(BULLET"klass size: %d", size()); st->cr(); 3065 st->print(BULLET"access: "); access_flags().print_on(st); st->cr(); 3066 st->print(BULLET"state: "); st->print_cr("%s", state_names[_init_state]); 3067 st->print(BULLET"name: "); name()->print_value_on(st); st->cr(); 3068 st->print(BULLET"super: "); super()->print_value_on_maybe_null(st); st->cr(); 3069 st->print(BULLET"sub: "); 3070 Klass* sub = subklass(); 3071 int n; 3072 for (n = 0; sub != NULL; n++, sub = sub->next_sibling()) { 3073 if (n < MaxSubklassPrintSize) { 3074 sub->print_value_on(st); 3075 st->print(" "); 3076 } 3077 } 3078 if (n >= MaxSubklassPrintSize) st->print("(" INTX_FORMAT " more klasses...)", n - MaxSubklassPrintSize); 3079 st->cr(); 3080 3081 if (is_interface()) { 3082 st->print_cr(BULLET"nof implementors: %d", nof_implementors()); 3083 if (nof_implementors() == 1) { 3084 st->print_cr(BULLET"implementor: "); 3085 st->print(" "); 3086 implementor()->print_value_on(st); 3087 st->cr(); 3088 } 3089 } 3090 3091 st->print(BULLET"arrays: "); array_klasses()->print_value_on_maybe_null(st); st->cr(); 3092 st->print(BULLET"methods: "); methods()->print_value_on(st); st->cr(); 3093 if (Verbose || WizardMode) { 3094 Array<Method*>* method_array = methods(); 3095 for (int i = 0; i < method_array->length(); i++) { 3096 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr(); 3097 } 3098 } 3099 st->print(BULLET"method ordering: "); method_ordering()->print_value_on(st); st->cr(); 3100 st->print(BULLET"default_methods: "); default_methods()->print_value_on(st); st->cr(); 3101 if (Verbose && default_methods() != NULL) { 3102 Array<Method*>* method_array = default_methods(); 3103 for (int i = 0; i < method_array->length(); i++) { 3104 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr(); 3105 } 3106 } 3107 if (default_vtable_indices() != NULL) { 3108 st->print(BULLET"default vtable indices: "); default_vtable_indices()->print_value_on(st); st->cr(); 3109 } 3110 st->print(BULLET"local interfaces: "); local_interfaces()->print_value_on(st); st->cr(); 3111 st->print(BULLET"trans. interfaces: "); transitive_interfaces()->print_value_on(st); st->cr(); 3112 st->print(BULLET"constants: "); constants()->print_value_on(st); st->cr(); 3113 if (class_loader_data() != NULL) { 3114 st->print(BULLET"class loader data: "); 3115 class_loader_data()->print_value_on(st); 3116 st->cr(); 3117 } 3118 st->print(BULLET"host class: "); host_klass()->print_value_on_maybe_null(st); st->cr(); 3119 if (source_file_name() != NULL) { 3120 st->print(BULLET"source file: "); 3121 source_file_name()->print_value_on(st); 3122 st->cr(); 3123 } 3124 if (source_debug_extension() != NULL) { 3125 st->print(BULLET"source debug extension: "); 3126 st->print("%s", source_debug_extension()); 3127 st->cr(); 3128 } 3129 st->print(BULLET"class annotations: "); class_annotations()->print_value_on(st); st->cr(); 3130 st->print(BULLET"class type annotations: "); class_type_annotations()->print_value_on(st); st->cr(); 3131 st->print(BULLET"field annotations: "); fields_annotations()->print_value_on(st); st->cr(); 3132 st->print(BULLET"field type annotations: "); fields_type_annotations()->print_value_on(st); st->cr(); 3133 { 3134 bool have_pv = false; 3135 // previous versions are linked together through the InstanceKlass 3136 for (InstanceKlass* pv_node = previous_versions(); 3137 pv_node != NULL; 3138 pv_node = pv_node->previous_versions()) { 3139 if (!have_pv) 3140 st->print(BULLET"previous version: "); 3141 have_pv = true; 3142 pv_node->constants()->print_value_on(st); 3143 } 3144 if (have_pv) st->cr(); 3145 } 3146 3147 if (generic_signature() != NULL) { 3148 st->print(BULLET"generic signature: "); 3149 generic_signature()->print_value_on(st); 3150 st->cr(); 3151 } 3152 st->print(BULLET"inner classes: "); inner_classes()->print_value_on(st); st->cr(); 3153 st->print(BULLET"nest members: "); nest_members()->print_value_on(st); st->cr(); 3154 st->print(BULLET"java mirror: "); java_mirror()->print_value_on(st); st->cr(); 3155 st->print(BULLET"vtable length %d (start addr: " INTPTR_FORMAT ")", vtable_length(), p2i(start_of_vtable())); st->cr(); 3156 if (vtable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_vtable(), vtable_length(), st); 3157 st->print(BULLET"itable length %d (start addr: " INTPTR_FORMAT ")", itable_length(), p2i(start_of_itable())); st->cr(); 3158 if (itable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_itable(), itable_length(), st); 3159 st->print_cr(BULLET"---- static fields (%d words):", static_field_size()); 3160 FieldPrinter print_static_field(st); 3161 ((InstanceKlass*)this)->do_local_static_fields(&print_static_field); 3162 st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size()); 3163 FieldPrinter print_nonstatic_field(st); 3164 InstanceKlass* ik = const_cast<InstanceKlass*>(this); 3165 ik->do_nonstatic_fields(&print_nonstatic_field); 3166 3167 st->print(BULLET"non-static oop maps: "); 3168 OopMapBlock* map = start_of_nonstatic_oop_maps(); 3169 OopMapBlock* end_map = map + nonstatic_oop_map_count(); 3170 while (map < end_map) { 3171 st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1)); 3172 map++; 3173 } 3174 st->cr(); 3175 } 3176 3177 #endif //PRODUCT 3178 3179 void InstanceKlass::print_value_on(outputStream* st) const { 3180 assert(is_klass(), "must be klass"); 3181 if (Verbose || WizardMode) access_flags().print_on(st); 3182 name()->print_value_on(st); 3183 } 3184 3185 #ifndef PRODUCT 3186 3187 void FieldPrinter::do_field(fieldDescriptor* fd) { 3188 _st->print(BULLET); 3189 if (_obj == NULL) { 3190 fd->print_on(_st); 3191 _st->cr(); 3192 } else { 3193 fd->print_on_for(_st, _obj); 3194 _st->cr(); 3195 } 3196 } 3197 3198 3199 void InstanceKlass::oop_print_on(oop obj, outputStream* st) { 3200 Klass::oop_print_on(obj, st); 3201 3202 if (this == SystemDictionary::String_klass()) { 3203 typeArrayOop value = java_lang_String::value(obj); 3204 juint length = java_lang_String::length(obj); 3205 if (value != NULL && 3206 value->is_typeArray() && 3207 length <= (juint) value->length()) { 3208 st->print(BULLET"string: "); 3209 java_lang_String::print(obj, st); 3210 st->cr(); 3211 if (!WizardMode) return; // that is enough 3212 } 3213 } 3214 3215 st->print_cr(BULLET"---- fields (total size %d words):", oop_size(obj)); 3216 FieldPrinter print_field(st, obj); 3217 do_nonstatic_fields(&print_field); 3218 3219 if (this == SystemDictionary::Class_klass()) { 3220 st->print(BULLET"signature: "); 3221 java_lang_Class::print_signature(obj, st); 3222 st->cr(); 3223 Klass* mirrored_klass = java_lang_Class::as_Klass(obj); 3224 st->print(BULLET"fake entry for mirror: "); 3225 mirrored_klass->print_value_on_maybe_null(st); 3226 st->cr(); 3227 Klass* array_klass = java_lang_Class::array_klass_acquire(obj); 3228 st->print(BULLET"fake entry for array: "); 3229 array_klass->print_value_on_maybe_null(st); 3230 st->cr(); 3231 st->print_cr(BULLET"fake entry for oop_size: %d", java_lang_Class::oop_size(obj)); 3232 st->print_cr(BULLET"fake entry for static_oop_field_count: %d", java_lang_Class::static_oop_field_count(obj)); 3233 Klass* real_klass = java_lang_Class::as_Klass(obj); 3234 if (real_klass != NULL && real_klass->is_instance_klass()) { 3235 InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field); 3236 } 3237 } else if (this == SystemDictionary::MethodType_klass()) { 3238 st->print(BULLET"signature: "); 3239 java_lang_invoke_MethodType::print_signature(obj, st); 3240 st->cr(); 3241 } 3242 } 3243 3244 #endif //PRODUCT 3245 3246 void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) { 3247 st->print("a "); 3248 name()->print_value_on(st); 3249 obj->print_address_on(st); 3250 if (this == SystemDictionary::String_klass() 3251 && java_lang_String::value(obj) != NULL) { 3252 ResourceMark rm; 3253 int len = java_lang_String::length(obj); 3254 int plen = (len < 24 ? len : 12); 3255 char* str = java_lang_String::as_utf8_string(obj, 0, plen); 3256 st->print(" = \"%s\"", str); 3257 if (len > plen) 3258 st->print("...[%d]", len); 3259 } else if (this == SystemDictionary::Class_klass()) { 3260 Klass* k = java_lang_Class::as_Klass(obj); 3261 st->print(" = "); 3262 if (k != NULL) { 3263 k->print_value_on(st); 3264 } else { 3265 const char* tname = type2name(java_lang_Class::primitive_type(obj)); 3266 st->print("%s", tname ? tname : "type?"); 3267 } 3268 } else if (this == SystemDictionary::MethodType_klass()) { 3269 st->print(" = "); 3270 java_lang_invoke_MethodType::print_signature(obj, st); 3271 } else if (java_lang_boxing_object::is_instance(obj)) { 3272 st->print(" = "); 3273 java_lang_boxing_object::print(obj, st); 3274 } else if (this == SystemDictionary::LambdaForm_klass()) { 3275 oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj); 3276 if (vmentry != NULL) { 3277 st->print(" => "); 3278 vmentry->print_value_on(st); 3279 } 3280 } else if (this == SystemDictionary::MemberName_klass()) { 3281 Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj); 3282 if (vmtarget != NULL) { 3283 st->print(" = "); 3284 vmtarget->print_value_on(st); 3285 } else { 3286 java_lang_invoke_MemberName::clazz(obj)->print_value_on(st); 3287 st->print("."); 3288 java_lang_invoke_MemberName::name(obj)->print_value_on(st); 3289 } 3290 } 3291 } 3292 3293 const char* InstanceKlass::internal_name() const { 3294 return external_name(); 3295 } 3296 3297 void InstanceKlass::print_class_load_logging(ClassLoaderData* loader_data, 3298 const char* module_name, 3299 const ClassFileStream* cfs) const { 3300 if (!log_is_enabled(Info, class, load)) { 3301 return; 3302 } 3303 3304 ResourceMark rm; 3305 LogMessage(class, load) msg; 3306 stringStream info_stream; 3307 3308 // Name and class hierarchy info 3309 info_stream.print("%s", external_name()); 3310 3311 // Source 3312 if (cfs != NULL) { 3313 if (cfs->source() != NULL) { 3314 if (module_name != NULL) { 3315 if (ClassLoader::is_modules_image(cfs->source())) { 3316 info_stream.print(" source: jrt:/%s", module_name); 3317 } else { 3318 info_stream.print(" source: %s", cfs->source()); 3319 } 3320 } else { 3321 info_stream.print(" source: %s", cfs->source()); 3322 } 3323 } else if (loader_data == ClassLoaderData::the_null_class_loader_data()) { 3324 Thread* THREAD = Thread::current(); 3325 Klass* caller = 3326 THREAD->is_Java_thread() 3327 ? ((JavaThread*)THREAD)->security_get_caller_class(1) 3328 : NULL; 3329 // caller can be NULL, for example, during a JVMTI VM_Init hook 3330 if (caller != NULL) { 3331 info_stream.print(" source: instance of %s", caller->external_name()); 3332 } else { 3333 // source is unknown 3334 } 3335 } else { 3336 oop class_loader = loader_data->class_loader(); 3337 info_stream.print(" source: %s", class_loader->klass()->external_name()); 3338 } 3339 } else { 3340 info_stream.print(" source: shared objects file"); 3341 } 3342 3343 msg.info("%s", info_stream.as_string()); 3344 3345 if (log_is_enabled(Debug, class, load)) { 3346 stringStream debug_stream; 3347 3348 // Class hierarchy info 3349 debug_stream.print(" klass: " INTPTR_FORMAT " super: " INTPTR_FORMAT, 3350 p2i(this), p2i(superklass())); 3351 3352 // Interfaces 3353 if (local_interfaces() != NULL && local_interfaces()->length() > 0) { 3354 debug_stream.print(" interfaces:"); 3355 int length = local_interfaces()->length(); 3356 for (int i = 0; i < length; i++) { 3357 debug_stream.print(" " INTPTR_FORMAT, 3358 p2i(InstanceKlass::cast(local_interfaces()->at(i)))); 3359 } 3360 } 3361 3362 // Class loader 3363 debug_stream.print(" loader: ["); 3364 loader_data->print_value_on(&debug_stream); 3365 debug_stream.print("]"); 3366 3367 // Classfile checksum 3368 if (cfs) { 3369 debug_stream.print(" bytes: %d checksum: %08x", 3370 cfs->length(), 3371 ClassLoader::crc32(0, (const char*)cfs->buffer(), 3372 cfs->length())); 3373 } 3374 3375 msg.debug("%s", debug_stream.as_string()); 3376 } 3377 } 3378 3379 #if INCLUDE_SERVICES 3380 // Size Statistics 3381 void InstanceKlass::collect_statistics(KlassSizeStats *sz) const { 3382 Klass::collect_statistics(sz); 3383 3384 sz->_inst_size = wordSize * size_helper(); 3385 sz->_vtab_bytes = wordSize * vtable_length(); 3386 sz->_itab_bytes = wordSize * itable_length(); 3387 sz->_nonstatic_oopmap_bytes = wordSize * nonstatic_oop_map_size(); 3388 3389 int n = 0; 3390 n += (sz->_methods_array_bytes = sz->count_array(methods())); 3391 n += (sz->_method_ordering_bytes = sz->count_array(method_ordering())); 3392 n += (sz->_local_interfaces_bytes = sz->count_array(local_interfaces())); 3393 n += (sz->_transitive_interfaces_bytes = sz->count_array(transitive_interfaces())); 3394 n += (sz->_fields_bytes = sz->count_array(fields())); 3395 n += (sz->_inner_classes_bytes = sz->count_array(inner_classes())); 3396 n += (sz->_nest_members_bytes = sz->count_array(nest_members())); 3397 sz->_ro_bytes += n; 3398 3399 const ConstantPool* cp = constants(); 3400 if (cp) { 3401 cp->collect_statistics(sz); 3402 } 3403 3404 const Annotations* anno = annotations(); 3405 if (anno) { 3406 anno->collect_statistics(sz); 3407 } 3408 3409 const Array<Method*>* methods_array = methods(); 3410 if (methods()) { 3411 for (int i = 0; i < methods_array->length(); i++) { 3412 Method* method = methods_array->at(i); 3413 if (method) { 3414 sz->_method_count ++; 3415 method->collect_statistics(sz); 3416 } 3417 } 3418 } 3419 } 3420 #endif // INCLUDE_SERVICES 3421 3422 // Verification 3423 3424 class VerifyFieldClosure: public OopClosure { 3425 protected: 3426 template <class T> void do_oop_work(T* p) { 3427 oop obj = RawAccess<>::oop_load(p); 3428 if (!oopDesc::is_oop_or_null(obj)) { 3429 tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p2i(p), p2i(obj)); 3430 Universe::print_on(tty); 3431 guarantee(false, "boom"); 3432 } 3433 } 3434 public: 3435 virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); } 3436 virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); } 3437 }; 3438 3439 void InstanceKlass::verify_on(outputStream* st) { 3440 #ifndef PRODUCT 3441 // Avoid redundant verifies, this really should be in product. 3442 if (_verify_count == Universe::verify_count()) return; 3443 _verify_count = Universe::verify_count(); 3444 #endif 3445 3446 // Verify Klass 3447 Klass::verify_on(st); 3448 3449 // Verify that klass is present in ClassLoaderData 3450 guarantee(class_loader_data()->contains_klass(this), 3451 "this class isn't found in class loader data"); 3452 3453 // Verify vtables 3454 if (is_linked()) { 3455 // $$$ This used to be done only for m/s collections. Doing it 3456 // always seemed a valid generalization. (DLD -- 6/00) 3457 vtable().verify(st); 3458 } 3459 3460 // Verify first subklass 3461 if (subklass() != NULL) { 3462 guarantee(subklass()->is_klass(), "should be klass"); 3463 } 3464 3465 // Verify siblings 3466 Klass* super = this->super(); 3467 Klass* sib = next_sibling(); 3468 if (sib != NULL) { 3469 if (sib == this) { 3470 fatal("subclass points to itself " PTR_FORMAT, p2i(sib)); 3471 } 3472 3473 guarantee(sib->is_klass(), "should be klass"); 3474 guarantee(sib->super() == super, "siblings should have same superklass"); 3475 } 3476 3477 // Verify implementor fields 3478 Klass* im = implementor(); 3479 if (im != NULL) { 3480 guarantee(is_interface(), "only interfaces should have implementor set"); 3481 guarantee(im->is_klass(), "should be klass"); 3482 guarantee(!im->is_interface() || im == this, 3483 "implementors cannot be interfaces"); 3484 } 3485 3486 // Verify local interfaces 3487 if (local_interfaces()) { 3488 Array<Klass*>* local_interfaces = this->local_interfaces(); 3489 for (int j = 0; j < local_interfaces->length(); j++) { 3490 Klass* e = local_interfaces->at(j); 3491 guarantee(e->is_klass() && e->is_interface(), "invalid local interface"); 3492 } 3493 } 3494 3495 // Verify transitive interfaces 3496 if (transitive_interfaces() != NULL) { 3497 Array<Klass*>* transitive_interfaces = this->transitive_interfaces(); 3498 for (int j = 0; j < transitive_interfaces->length(); j++) { 3499 Klass* e = transitive_interfaces->at(j); 3500 guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface"); 3501 } 3502 } 3503 3504 // Verify methods 3505 if (methods() != NULL) { 3506 Array<Method*>* methods = this->methods(); 3507 for (int j = 0; j < methods->length(); j++) { 3508 guarantee(methods->at(j)->is_method(), "non-method in methods array"); 3509 } 3510 for (int j = 0; j < methods->length() - 1; j++) { 3511 Method* m1 = methods->at(j); 3512 Method* m2 = methods->at(j + 1); 3513 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly"); 3514 } 3515 } 3516 3517 // Verify method ordering 3518 if (method_ordering() != NULL) { 3519 Array<int>* method_ordering = this->method_ordering(); 3520 int length = method_ordering->length(); 3521 if (JvmtiExport::can_maintain_original_method_order() || 3522 ((UseSharedSpaces || DumpSharedSpaces) && length != 0)) { 3523 guarantee(length == methods()->length(), "invalid method ordering length"); 3524 jlong sum = 0; 3525 for (int j = 0; j < length; j++) { 3526 int original_index = method_ordering->at(j); 3527 guarantee(original_index >= 0, "invalid method ordering index"); 3528 guarantee(original_index < length, "invalid method ordering index"); 3529 sum += original_index; 3530 } 3531 // Verify sum of indices 0,1,...,length-1 3532 guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum"); 3533 } else { 3534 guarantee(length == 0, "invalid method ordering length"); 3535 } 3536 } 3537 3538 // Verify default methods 3539 if (default_methods() != NULL) { 3540 Array<Method*>* methods = this->default_methods(); 3541 for (int j = 0; j < methods->length(); j++) { 3542 guarantee(methods->at(j)->is_method(), "non-method in methods array"); 3543 } 3544 for (int j = 0; j < methods->length() - 1; j++) { 3545 Method* m1 = methods->at(j); 3546 Method* m2 = methods->at(j + 1); 3547 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly"); 3548 } 3549 } 3550 3551 // Verify JNI static field identifiers 3552 if (jni_ids() != NULL) { 3553 jni_ids()->verify(this); 3554 } 3555 3556 // Verify other fields 3557 if (array_klasses() != NULL) { 3558 guarantee(array_klasses()->is_klass(), "should be klass"); 3559 } 3560 if (constants() != NULL) { 3561 guarantee(constants()->is_constantPool(), "should be constant pool"); 3562 } 3563 const Klass* host = host_klass(); 3564 if (host != NULL) { 3565 guarantee(host->is_klass(), "should be klass"); 3566 } 3567 } 3568 3569 void InstanceKlass::oop_verify_on(oop obj, outputStream* st) { 3570 Klass::oop_verify_on(obj, st); 3571 VerifyFieldClosure blk; 3572 obj->oop_iterate_no_header(&blk); 3573 } 3574 3575 3576 // JNIid class for jfieldIDs only 3577 // Note to reviewers: 3578 // These JNI functions are just moved over to column 1 and not changed 3579 // in the compressed oops workspace. 3580 JNIid::JNIid(Klass* holder, int offset, JNIid* next) { 3581 _holder = holder; 3582 _offset = offset; 3583 _next = next; 3584 debug_only(_is_static_field_id = false;) 3585 } 3586 3587 3588 JNIid* JNIid::find(int offset) { 3589 JNIid* current = this; 3590 while (current != NULL) { 3591 if (current->offset() == offset) return current; 3592 current = current->next(); 3593 } 3594 return NULL; 3595 } 3596 3597 void JNIid::deallocate(JNIid* current) { 3598 while (current != NULL) { 3599 JNIid* next = current->next(); 3600 delete current; 3601 current = next; 3602 } 3603 } 3604 3605 3606 void JNIid::verify(Klass* holder) { 3607 int first_field_offset = InstanceMirrorKlass::offset_of_static_fields(); 3608 int end_field_offset; 3609 end_field_offset = first_field_offset + (InstanceKlass::cast(holder)->static_field_size() * wordSize); 3610 3611 JNIid* current = this; 3612 while (current != NULL) { 3613 guarantee(current->holder() == holder, "Invalid klass in JNIid"); 3614 #ifdef ASSERT 3615 int o = current->offset(); 3616 if (current->is_static_field_id()) { 3617 guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid"); 3618 } 3619 #endif 3620 current = current->next(); 3621 } 3622 } 3623 3624 oop InstanceKlass::holder_phantom() const { 3625 return class_loader_data()->holder_phantom(); 3626 } 3627 3628 #ifdef ASSERT 3629 void InstanceKlass::set_init_state(ClassState state) { 3630 bool good_state = is_shared() ? (_init_state <= state) 3631 : (_init_state < state); 3632 assert(good_state || state == allocated, "illegal state transition"); 3633 _init_state = (u1)state; 3634 } 3635 #endif 3636 3637 #if INCLUDE_JVMTI 3638 3639 // RedefineClasses() support for previous versions 3640 3641 // Globally, there is at least one previous version of a class to walk 3642 // during class unloading, which is saved because old methods in the class 3643 // are still running. Otherwise the previous version list is cleaned up. 3644 bool InstanceKlass::_has_previous_versions = false; 3645 3646 // Returns true if there are previous versions of a class for class 3647 // unloading only. Also resets the flag to false. purge_previous_version 3648 // will set the flag to true if there are any left, i.e., if there's any 3649 // work to do for next time. This is to avoid the expensive code cache 3650 // walk in CLDG::do_unloading(). 3651 bool InstanceKlass::has_previous_versions_and_reset() { 3652 bool ret = _has_previous_versions; 3653 log_trace(redefine, class, iklass, purge)("Class unloading: has_previous_versions = %s", 3654 ret ? "true" : "false"); 3655 _has_previous_versions = false; 3656 return ret; 3657 } 3658 3659 // Purge previous versions before adding new previous versions of the class and 3660 // during class unloading. 3661 void InstanceKlass::purge_previous_version_list() { 3662 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint"); 3663 assert(has_been_redefined(), "Should only be called for main class"); 3664 3665 // Quick exit. 3666 if (previous_versions() == NULL) { 3667 return; 3668 } 3669 3670 // This klass has previous versions so see what we can cleanup 3671 // while it is safe to do so. 3672 3673 int deleted_count = 0; // leave debugging breadcrumbs 3674 int live_count = 0; 3675 ClassLoaderData* loader_data = class_loader_data(); 3676 assert(loader_data != NULL, "should never be null"); 3677 3678 ResourceMark rm; 3679 log_trace(redefine, class, iklass, purge)("%s: previous versions", external_name()); 3680 3681 // previous versions are linked together through the InstanceKlass 3682 InstanceKlass* pv_node = previous_versions(); 3683 InstanceKlass* last = this; 3684 int version = 0; 3685 3686 // check the previous versions list 3687 for (; pv_node != NULL; ) { 3688 3689 ConstantPool* pvcp = pv_node->constants(); 3690 assert(pvcp != NULL, "cp ref was unexpectedly cleared"); 3691 3692 if (!pvcp->on_stack()) { 3693 // If the constant pool isn't on stack, none of the methods 3694 // are executing. Unlink this previous_version. 3695 // The previous version InstanceKlass is on the ClassLoaderData deallocate list 3696 // so will be deallocated during the next phase of class unloading. 3697 log_trace(redefine, class, iklass, purge) 3698 ("previous version " INTPTR_FORMAT " is dead.", p2i(pv_node)); 3699 // For debugging purposes. 3700 pv_node->set_is_scratch_class(); 3701 // Unlink from previous version list. 3702 assert(pv_node->class_loader_data() == loader_data, "wrong loader_data"); 3703 InstanceKlass* next = pv_node->previous_versions(); 3704 pv_node->link_previous_versions(NULL); // point next to NULL 3705 last->link_previous_versions(next); 3706 // Add to the deallocate list after unlinking 3707 loader_data->add_to_deallocate_list(pv_node); 3708 pv_node = next; 3709 deleted_count++; 3710 version++; 3711 continue; 3712 } else { 3713 log_trace(redefine, class, iklass, purge)("previous version " INTPTR_FORMAT " is alive", p2i(pv_node)); 3714 assert(pvcp->pool_holder() != NULL, "Constant pool with no holder"); 3715 guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack"); 3716 live_count++; 3717 // found a previous version for next time we do class unloading 3718 _has_previous_versions = true; 3719 } 3720 3721 // At least one method is live in this previous version. 3722 // Reset dead EMCP methods not to get breakpoints. 3723 // All methods are deallocated when all of the methods for this class are no 3724 // longer running. 3725 Array<Method*>* method_refs = pv_node->methods(); 3726 if (method_refs != NULL) { 3727 log_trace(redefine, class, iklass, purge)("previous methods length=%d", method_refs->length()); 3728 for (int j = 0; j < method_refs->length(); j++) { 3729 Method* method = method_refs->at(j); 3730 3731 if (!method->on_stack()) { 3732 // no breakpoints for non-running methods 3733 if (method->is_running_emcp()) { 3734 method->set_running_emcp(false); 3735 } 3736 } else { 3737 assert (method->is_obsolete() || method->is_running_emcp(), 3738 "emcp method cannot run after emcp bit is cleared"); 3739 log_trace(redefine, class, iklass, purge) 3740 ("purge: %s(%s): prev method @%d in version @%d is alive", 3741 method->name()->as_C_string(), method->signature()->as_C_string(), j, version); 3742 } 3743 } 3744 } 3745 // next previous version 3746 last = pv_node; 3747 pv_node = pv_node->previous_versions(); 3748 version++; 3749 } 3750 log_trace(redefine, class, iklass, purge) 3751 ("previous version stats: live=%d, deleted=%d", live_count, deleted_count); 3752 } 3753 3754 void InstanceKlass::mark_newly_obsolete_methods(Array<Method*>* old_methods, 3755 int emcp_method_count) { 3756 int obsolete_method_count = old_methods->length() - emcp_method_count; 3757 3758 if (emcp_method_count != 0 && obsolete_method_count != 0 && 3759 _previous_versions != NULL) { 3760 // We have a mix of obsolete and EMCP methods so we have to 3761 // clear out any matching EMCP method entries the hard way. 3762 int local_count = 0; 3763 for (int i = 0; i < old_methods->length(); i++) { 3764 Method* old_method = old_methods->at(i); 3765 if (old_method->is_obsolete()) { 3766 // only obsolete methods are interesting 3767 Symbol* m_name = old_method->name(); 3768 Symbol* m_signature = old_method->signature(); 3769 3770 // previous versions are linked together through the InstanceKlass 3771 int j = 0; 3772 for (InstanceKlass* prev_version = _previous_versions; 3773 prev_version != NULL; 3774 prev_version = prev_version->previous_versions(), j++) { 3775 3776 Array<Method*>* method_refs = prev_version->methods(); 3777 for (int k = 0; k < method_refs->length(); k++) { 3778 Method* method = method_refs->at(k); 3779 3780 if (!method->is_obsolete() && 3781 method->name() == m_name && 3782 method->signature() == m_signature) { 3783 // The current RedefineClasses() call has made all EMCP 3784 // versions of this method obsolete so mark it as obsolete 3785 log_trace(redefine, class, iklass, add) 3786 ("%s(%s): flush obsolete method @%d in version @%d", 3787 m_name->as_C_string(), m_signature->as_C_string(), k, j); 3788 3789 method->set_is_obsolete(); 3790 break; 3791 } 3792 } 3793 3794 // The previous loop may not find a matching EMCP method, but 3795 // that doesn't mean that we can optimize and not go any 3796 // further back in the PreviousVersion generations. The EMCP 3797 // method for this generation could have already been made obsolete, 3798 // but there still may be an older EMCP method that has not 3799 // been made obsolete. 3800 } 3801 3802 if (++local_count >= obsolete_method_count) { 3803 // no more obsolete methods so bail out now 3804 break; 3805 } 3806 } 3807 } 3808 } 3809 } 3810 3811 // Save the scratch_class as the previous version if any of the methods are running. 3812 // The previous_versions are used to set breakpoints in EMCP methods and they are 3813 // also used to clean MethodData links to redefined methods that are no longer running. 3814 void InstanceKlass::add_previous_version(InstanceKlass* scratch_class, 3815 int emcp_method_count) { 3816 assert(Thread::current()->is_VM_thread(), 3817 "only VMThread can add previous versions"); 3818 3819 ResourceMark rm; 3820 log_trace(redefine, class, iklass, add) 3821 ("adding previous version ref for %s, EMCP_cnt=%d", scratch_class->external_name(), emcp_method_count); 3822 3823 // Clean out old previous versions for this class 3824 purge_previous_version_list(); 3825 3826 // Mark newly obsolete methods in remaining previous versions. An EMCP method from 3827 // a previous redefinition may be made obsolete by this redefinition. 3828 Array<Method*>* old_methods = scratch_class->methods(); 3829 mark_newly_obsolete_methods(old_methods, emcp_method_count); 3830 3831 // If the constant pool for this previous version of the class 3832 // is not marked as being on the stack, then none of the methods 3833 // in this previous version of the class are on the stack so 3834 // we don't need to add this as a previous version. 3835 ConstantPool* cp_ref = scratch_class->constants(); 3836 if (!cp_ref->on_stack()) { 3837 log_trace(redefine, class, iklass, add)("scratch class not added; no methods are running"); 3838 // For debugging purposes. 3839 scratch_class->set_is_scratch_class(); 3840 scratch_class->class_loader_data()->add_to_deallocate_list(scratch_class); 3841 return; 3842 } 3843 3844 if (emcp_method_count != 0) { 3845 // At least one method is still running, check for EMCP methods 3846 for (int i = 0; i < old_methods->length(); i++) { 3847 Method* old_method = old_methods->at(i); 3848 if (!old_method->is_obsolete() && old_method->on_stack()) { 3849 // if EMCP method (not obsolete) is on the stack, mark as EMCP so that 3850 // we can add breakpoints for it. 3851 3852 // We set the method->on_stack bit during safepoints for class redefinition 3853 // and use this bit to set the is_running_emcp bit. 3854 // After the safepoint, the on_stack bit is cleared and the running emcp 3855 // method may exit. If so, we would set a breakpoint in a method that 3856 // is never reached, but this won't be noticeable to the programmer. 3857 old_method->set_running_emcp(true); 3858 log_trace(redefine, class, iklass, add) 3859 ("EMCP method %s is on_stack " INTPTR_FORMAT, old_method->name_and_sig_as_C_string(), p2i(old_method)); 3860 } else if (!old_method->is_obsolete()) { 3861 log_trace(redefine, class, iklass, add) 3862 ("EMCP method %s is NOT on_stack " INTPTR_FORMAT, old_method->name_and_sig_as_C_string(), p2i(old_method)); 3863 } 3864 } 3865 } 3866 3867 // Add previous version if any methods are still running. 3868 // Set has_previous_version flag for processing during class unloading. 3869 _has_previous_versions = true; 3870 log_trace(redefine, class, iklass, add) ("scratch class added; one of its methods is on_stack."); 3871 assert(scratch_class->previous_versions() == NULL, "shouldn't have a previous version"); 3872 scratch_class->link_previous_versions(previous_versions()); 3873 link_previous_versions(scratch_class); 3874 } // end add_previous_version() 3875 3876 #endif // INCLUDE_JVMTI 3877 3878 Method* InstanceKlass::method_with_idnum(int idnum) { 3879 Method* m = NULL; 3880 if (idnum < methods()->length()) { 3881 m = methods()->at(idnum); 3882 } 3883 if (m == NULL || m->method_idnum() != idnum) { 3884 for (int index = 0; index < methods()->length(); ++index) { 3885 m = methods()->at(index); 3886 if (m->method_idnum() == idnum) { 3887 return m; 3888 } 3889 } 3890 // None found, return null for the caller to handle. 3891 return NULL; 3892 } 3893 return m; 3894 } 3895 3896 3897 Method* InstanceKlass::method_with_orig_idnum(int idnum) { 3898 if (idnum >= methods()->length()) { 3899 return NULL; 3900 } 3901 Method* m = methods()->at(idnum); 3902 if (m != NULL && m->orig_method_idnum() == idnum) { 3903 return m; 3904 } 3905 // Obsolete method idnum does not match the original idnum 3906 for (int index = 0; index < methods()->length(); ++index) { 3907 m = methods()->at(index); 3908 if (m->orig_method_idnum() == idnum) { 3909 return m; 3910 } 3911 } 3912 // None found, return null for the caller to handle. 3913 return NULL; 3914 } 3915 3916 3917 Method* InstanceKlass::method_with_orig_idnum(int idnum, int version) { 3918 InstanceKlass* holder = get_klass_version(version); 3919 if (holder == NULL) { 3920 return NULL; // The version of klass is gone, no method is found 3921 } 3922 Method* method = holder->method_with_orig_idnum(idnum); 3923 return method; 3924 } 3925 3926 #if INCLUDE_JVMTI 3927 JvmtiCachedClassFileData* InstanceKlass::get_cached_class_file() { 3928 if (MetaspaceShared::is_in_shared_metaspace(_cached_class_file)) { 3929 // Ignore the archived class stream data 3930 return NULL; 3931 } else { 3932 return _cached_class_file; 3933 } 3934 } 3935 3936 jint InstanceKlass::get_cached_class_file_len() { 3937 return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file); 3938 } 3939 3940 unsigned char * InstanceKlass::get_cached_class_file_bytes() { 3941 return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file); 3942 } 3943 3944 #if INCLUDE_CDS 3945 JvmtiCachedClassFileData* InstanceKlass::get_archived_class_data() { 3946 if (DumpSharedSpaces) { 3947 return _cached_class_file; 3948 } else { 3949 assert(this->is_shared(), "class should be shared"); 3950 if (MetaspaceShared::is_in_shared_metaspace(_cached_class_file)) { 3951 return _cached_class_file; 3952 } else { 3953 return NULL; 3954 } 3955 } 3956 } 3957 #endif 3958 #endif