1 /*
   2  * Copyright (c) 1997, 2015, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #include "precompiled.hpp"
  26 #include "classfile/classFileParser.hpp"
  27 #include "classfile/javaClasses.hpp"
  28 #include "classfile/systemDictionary.hpp"
  29 #include "classfile/verifier.hpp"
  30 #include "classfile/vmSymbols.hpp"
  31 #include "code/dependencyContext.hpp"
  32 #include "compiler/compileBroker.hpp"
  33 #include "gc/shared/collectedHeap.inline.hpp"
  34 #include "gc/shared/specialized_oop_closures.hpp"
  35 #include "interpreter/oopMapCache.hpp"
  36 #include "interpreter/rewriter.hpp"
  37 #include "jvmtifiles/jvmti.h"
  38 #include "memory/heapInspection.hpp"
  39 #include "memory/iterator.inline.hpp"
  40 #include "memory/metadataFactory.hpp"
  41 #include "memory/oopFactory.hpp"
  42 #include "oops/fieldStreams.hpp"
  43 #include "oops/instanceClassLoaderKlass.hpp"
  44 #include "oops/instanceKlass.inline.hpp"
  45 #include "oops/instanceMirrorKlass.hpp"
  46 #include "oops/instanceOop.hpp"
  47 #include "oops/klass.inline.hpp"
  48 #include "oops/method.hpp"
  49 #include "oops/oop.inline.hpp"
  50 #include "oops/symbol.hpp"
  51 #include "prims/jvmtiExport.hpp"
  52 #include "prims/jvmtiRedefineClasses.hpp"
  53 #include "prims/jvmtiRedefineClassesTrace.hpp"
  54 #include "prims/jvmtiThreadState.hpp"
  55 #include "prims/methodComparator.hpp"
  56 #include "runtime/atomic.inline.hpp"
  57 #include "runtime/fieldDescriptor.hpp"
  58 #include "runtime/handles.inline.hpp"
  59 #include "runtime/javaCalls.hpp"
  60 #include "runtime/mutexLocker.hpp"
  61 #include "runtime/orderAccess.inline.hpp"
  62 #include "runtime/thread.inline.hpp"
  63 #include "services/classLoadingService.hpp"
  64 #include "services/threadService.hpp"
  65 #include "utilities/dtrace.hpp"
  66 #include "utilities/macros.hpp"
  67 #include "logging/log.hpp"
  68 #ifdef COMPILER1
  69 #include "c1/c1_Compiler.hpp"
  70 #endif
  71 
  72 #ifdef DTRACE_ENABLED
  73 
  74 
  75 #define HOTSPOT_CLASS_INITIALIZATION_required HOTSPOT_CLASS_INITIALIZATION_REQUIRED
  76 #define HOTSPOT_CLASS_INITIALIZATION_recursive HOTSPOT_CLASS_INITIALIZATION_RECURSIVE
  77 #define HOTSPOT_CLASS_INITIALIZATION_concurrent HOTSPOT_CLASS_INITIALIZATION_CONCURRENT
  78 #define HOTSPOT_CLASS_INITIALIZATION_erroneous HOTSPOT_CLASS_INITIALIZATION_ERRONEOUS
  79 #define HOTSPOT_CLASS_INITIALIZATION_super__failed HOTSPOT_CLASS_INITIALIZATION_SUPER_FAILED
  80 #define HOTSPOT_CLASS_INITIALIZATION_clinit HOTSPOT_CLASS_INITIALIZATION_CLINIT
  81 #define HOTSPOT_CLASS_INITIALIZATION_error HOTSPOT_CLASS_INITIALIZATION_ERROR
  82 #define HOTSPOT_CLASS_INITIALIZATION_end HOTSPOT_CLASS_INITIALIZATION_END
  83 #define DTRACE_CLASSINIT_PROBE(type, clss, thread_type)          \
  84   {                                                              \
  85     char* data = NULL;                                           \
  86     int len = 0;                                                 \
  87     Symbol* name = (clss)->name();                               \
  88     if (name != NULL) {                                          \
  89       data = (char*)name->bytes();                               \
  90       len = name->utf8_length();                                 \
  91     }                                                            \
  92     HOTSPOT_CLASS_INITIALIZATION_##type(                         \
  93       data, len, (clss)->class_loader(), thread_type);           \
  94   }
  95 
  96 #define DTRACE_CLASSINIT_PROBE_WAIT(type, clss, thread_type, wait) \
  97   {                                                              \
  98     char* data = NULL;                                           \
  99     int len = 0;                                                 \
 100     Symbol* name = (clss)->name();                               \
 101     if (name != NULL) {                                          \
 102       data = (char*)name->bytes();                               \
 103       len = name->utf8_length();                                 \
 104     }                                                            \
 105     HOTSPOT_CLASS_INITIALIZATION_##type(                         \
 106       data, len, (clss)->class_loader(), thread_type, wait);     \
 107   }
 108 
 109 #else //  ndef DTRACE_ENABLED
 110 
 111 #define DTRACE_CLASSINIT_PROBE(type, clss, thread_type)
 112 #define DTRACE_CLASSINIT_PROBE_WAIT(type, clss, thread_type, wait)
 113 
 114 #endif //  ndef DTRACE_ENABLED
 115 
 116 volatile int InstanceKlass::_total_instanceKlass_count = 0;
 117 
 118 static inline bool is_class_loader(const Symbol* class_name,
 119                                    const ClassFileParser& parser) {
 120   assert(class_name != NULL, "invariant");
 121 
 122   if (class_name == vmSymbols::java_lang_ClassLoader()) {
 123     return true;
 124   }
 125 
 126   if (SystemDictionary::ClassLoader_klass_loaded()) {
 127     const Klass* const super_klass = parser.super_klass();
 128     if (super_klass != NULL) {
 129       if (super_klass->is_subtype_of(SystemDictionary::ClassLoader_klass())) {
 130         return true;
 131       }
 132     }
 133   }
 134   return false;
 135 }
 136 
 137 InstanceKlass* InstanceKlass::allocate_instance_klass(const ClassFileParser& parser, TRAPS) {
 138   const int size = InstanceKlass::size(parser.vtable_size(),
 139                                        parser.itable_size(),
 140                                        nonstatic_oop_map_size(parser.total_oop_map_count()),
 141                                        parser.is_interface(),
 142                                        parser.is_anonymous());
 143 
 144   const Symbol* const class_name = parser.class_name();
 145   assert(class_name != NULL, "invariant");
 146   ClassLoaderData* loader_data = parser.loader_data();
 147   assert(loader_data != NULL, "invariant");
 148 
 149   InstanceKlass* ik;
 150 
 151   // Allocation
 152   if (REF_NONE == parser.reference_type()) {
 153     if (class_name == vmSymbols::java_lang_Class()) {
 154       // mirror
 155       ik = new (loader_data, size, THREAD) InstanceMirrorKlass(parser);
 156     }
 157     else if (is_class_loader(class_name, parser)) {
 158       // class loader
 159       ik = new (loader_data, size, THREAD) InstanceClassLoaderKlass(parser);
 160     }
 161     else {
 162       // normal
 163       ik = new (loader_data, size, THREAD) InstanceKlass(parser, InstanceKlass::_misc_kind_other);
 164     }
 165   }
 166   else {
 167     // reference
 168     ik = new (loader_data, size, THREAD) InstanceRefKlass(parser);
 169   }
 170 
 171   // Check for pending exception before adding to the loader data and incrementing
 172   // class count.  Can get OOM here.
 173   if (HAS_PENDING_EXCEPTION) {
 174     return NULL;
 175   }
 176 
 177   assert(ik != NULL, "invariant");
 178 
 179   const bool publicize = !parser.is_internal();
 180 
 181   // Add all classes to our internal class loader list here,
 182   // including classes in the bootstrap (NULL) class loader.
 183   loader_data->add_class(ik, publicize);
 184   Atomic::inc(&_total_instanceKlass_count);
 185 
 186   return ik;
 187 }
 188 
 189 
 190 // copy method ordering from resource area to Metaspace
 191 void InstanceKlass::copy_method_ordering(const intArray* m, TRAPS) {
 192   if (m != NULL) {
 193     // allocate a new array and copy contents (memcpy?)
 194     _method_ordering = MetadataFactory::new_array<int>(class_loader_data(), m->length(), CHECK);
 195     for (int i = 0; i < m->length(); i++) {
 196       _method_ordering->at_put(i, m->at(i));
 197     }
 198   } else {
 199     _method_ordering = Universe::the_empty_int_array();
 200   }
 201 }
 202 
 203 // create a new array of vtable_indices for default methods
 204 Array<int>* InstanceKlass::create_new_default_vtable_indices(int len, TRAPS) {
 205   Array<int>* vtable_indices = MetadataFactory::new_array<int>(class_loader_data(), len, CHECK_NULL);
 206   assert(default_vtable_indices() == NULL, "only create once");
 207   set_default_vtable_indices(vtable_indices);
 208   return vtable_indices;
 209 }
 210 
 211 InstanceKlass::InstanceKlass(const ClassFileParser& parser, unsigned kind) :
 212   _static_field_size(parser.static_field_size()),
 213   _nonstatic_oop_map_size(nonstatic_oop_map_size(parser.total_oop_map_count())),
 214   _vtable_len(parser.vtable_size()),
 215   _itable_len(parser.itable_size()),
 216   _reference_type(parser.reference_type()) {
 217     set_kind(kind);
 218     set_access_flags(parser.access_flags());
 219     set_is_anonymous(parser.is_anonymous());
 220     set_layout_helper(Klass::instance_layout_helper(parser.layout_size(),
 221                                                     false));
 222 
 223     assert(NULL == _methods, "underlying memory not zeroed?");
 224     assert(is_instance_klass(), "is layout incorrect?");
 225     assert(size_helper() == parser.layout_size(), "incorrect size_helper?");
 226 }
 227 
 228 void InstanceKlass::deallocate_methods(ClassLoaderData* loader_data,
 229                                        Array<Method*>* methods) {
 230   if (methods != NULL && methods != Universe::the_empty_method_array() &&
 231       !methods->is_shared()) {
 232     for (int i = 0; i < methods->length(); i++) {
 233       Method* method = methods->at(i);
 234       if (method == NULL) continue;  // maybe null if error processing
 235       // Only want to delete methods that are not executing for RedefineClasses.
 236       // The previous version will point to them so they're not totally dangling
 237       assert (!method->on_stack(), "shouldn't be called with methods on stack");
 238       MetadataFactory::free_metadata(loader_data, method);
 239     }
 240     MetadataFactory::free_array<Method*>(loader_data, methods);
 241   }
 242 }
 243 
 244 void InstanceKlass::deallocate_interfaces(ClassLoaderData* loader_data,
 245                                           const Klass* super_klass,
 246                                           Array<Klass*>* local_interfaces,
 247                                           Array<Klass*>* transitive_interfaces) {
 248   // Only deallocate transitive interfaces if not empty, same as super class
 249   // or same as local interfaces.  See code in parseClassFile.
 250   Array<Klass*>* ti = transitive_interfaces;
 251   if (ti != Universe::the_empty_klass_array() && ti != local_interfaces) {
 252     // check that the interfaces don't come from super class
 253     Array<Klass*>* sti = (super_klass == NULL) ? NULL :
 254                     InstanceKlass::cast(super_klass)->transitive_interfaces();
 255     if (ti != sti && ti != NULL && !ti->is_shared()) {
 256       MetadataFactory::free_array<Klass*>(loader_data, ti);
 257     }
 258   }
 259 
 260   // local interfaces can be empty
 261   if (local_interfaces != Universe::the_empty_klass_array() &&
 262       local_interfaces != NULL && !local_interfaces->is_shared()) {
 263     MetadataFactory::free_array<Klass*>(loader_data, local_interfaces);
 264   }
 265 }
 266 
 267 // This function deallocates the metadata and C heap pointers that the
 268 // InstanceKlass points to.
 269 void InstanceKlass::deallocate_contents(ClassLoaderData* loader_data) {
 270 
 271   // Orphan the mirror first, CMS thinks it's still live.
 272   if (java_mirror() != NULL) {
 273     java_lang_Class::set_klass(java_mirror(), NULL);
 274   }
 275 
 276   // Need to take this class off the class loader data list.
 277   loader_data->remove_class(this);
 278 
 279   // The array_klass for this class is created later, after error handling.
 280   // For class redefinition, we keep the original class so this scratch class
 281   // doesn't have an array class.  Either way, assert that there is nothing
 282   // to deallocate.
 283   assert(array_klasses() == NULL, "array classes shouldn't be created for this class yet");
 284 
 285   // Release C heap allocated data that this might point to, which includes
 286   // reference counting symbol names.
 287   release_C_heap_structures();
 288 
 289   deallocate_methods(loader_data, methods());
 290   set_methods(NULL);
 291 
 292   if (method_ordering() != NULL &&
 293       method_ordering() != Universe::the_empty_int_array() &&
 294       !method_ordering()->is_shared()) {
 295     MetadataFactory::free_array<int>(loader_data, method_ordering());
 296   }
 297   set_method_ordering(NULL);
 298 
 299   // default methods can be empty
 300   if (default_methods() != NULL &&
 301       default_methods() != Universe::the_empty_method_array() &&
 302       !default_methods()->is_shared()) {
 303     MetadataFactory::free_array<Method*>(loader_data, default_methods());
 304   }
 305   // Do NOT deallocate the default methods, they are owned by superinterfaces.
 306   set_default_methods(NULL);
 307 
 308   // default methods vtable indices can be empty
 309   if (default_vtable_indices() != NULL &&
 310       !default_vtable_indices()->is_shared()) {
 311     MetadataFactory::free_array<int>(loader_data, default_vtable_indices());
 312   }
 313   set_default_vtable_indices(NULL);
 314 
 315 
 316   // This array is in Klass, but remove it with the InstanceKlass since
 317   // this place would be the only caller and it can share memory with transitive
 318   // interfaces.
 319   if (secondary_supers() != NULL &&
 320       secondary_supers() != Universe::the_empty_klass_array() &&
 321       secondary_supers() != transitive_interfaces() &&
 322       !secondary_supers()->is_shared()) {
 323     MetadataFactory::free_array<Klass*>(loader_data, secondary_supers());
 324   }
 325   set_secondary_supers(NULL);
 326 
 327   deallocate_interfaces(loader_data, super(), local_interfaces(), transitive_interfaces());
 328   set_transitive_interfaces(NULL);
 329   set_local_interfaces(NULL);
 330 
 331   if (fields() != NULL && !fields()->is_shared()) {
 332     MetadataFactory::free_array<jushort>(loader_data, fields());
 333   }
 334   set_fields(NULL, 0);
 335 
 336   // If a method from a redefined class is using this constant pool, don't
 337   // delete it, yet.  The new class's previous version will point to this.
 338   if (constants() != NULL) {
 339     assert (!constants()->on_stack(), "shouldn't be called if anything is onstack");
 340     if (!constants()->is_shared()) {
 341       MetadataFactory::free_metadata(loader_data, constants());
 342     }
 343     // Delete any cached resolution errors for the constant pool
 344     SystemDictionary::delete_resolution_error(constants());
 345 
 346     set_constants(NULL);
 347   }
 348 
 349   if (inner_classes() != NULL &&
 350       inner_classes() != Universe::the_empty_short_array() &&
 351       !inner_classes()->is_shared()) {
 352     MetadataFactory::free_array<jushort>(loader_data, inner_classes());
 353   }
 354   set_inner_classes(NULL);
 355 
 356   // We should deallocate the Annotations instance if it's not in shared spaces.
 357   if (annotations() != NULL && !annotations()->is_shared()) {
 358     MetadataFactory::free_metadata(loader_data, annotations());
 359   }
 360   set_annotations(NULL);
 361 }
 362 
 363 bool InstanceKlass::should_be_initialized() const {
 364   return !is_initialized();
 365 }
 366 
 367 klassVtable* InstanceKlass::vtable() const {
 368   return new klassVtable(this, start_of_vtable(), vtable_length() / vtableEntry::size());
 369 }
 370 
 371 klassItable* InstanceKlass::itable() const {
 372   return new klassItable(instanceKlassHandle(this));
 373 }
 374 
 375 void InstanceKlass::eager_initialize(Thread *thread) {
 376   if (!EagerInitialization) return;
 377 
 378   if (this->is_not_initialized()) {
 379     // abort if the the class has a class initializer
 380     if (this->class_initializer() != NULL) return;
 381 
 382     // abort if it is java.lang.Object (initialization is handled in genesis)
 383     Klass* super = this->super();
 384     if (super == NULL) return;
 385 
 386     // abort if the super class should be initialized
 387     if (!InstanceKlass::cast(super)->is_initialized()) return;
 388 
 389     // call body to expose the this pointer
 390     instanceKlassHandle this_k(thread, this);
 391     eager_initialize_impl(this_k);
 392   }
 393 }
 394 
 395 // JVMTI spec thinks there are signers and protection domain in the
 396 // instanceKlass.  These accessors pretend these fields are there.
 397 // The hprof specification also thinks these fields are in InstanceKlass.
 398 oop InstanceKlass::protection_domain() const {
 399   // return the protection_domain from the mirror
 400   return java_lang_Class::protection_domain(java_mirror());
 401 }
 402 
 403 // To remove these from requires an incompatible change and CCC request.
 404 objArrayOop InstanceKlass::signers() const {
 405   // return the signers from the mirror
 406   return java_lang_Class::signers(java_mirror());
 407 }
 408 
 409 oop InstanceKlass::init_lock() const {
 410   // return the init lock from the mirror
 411   oop lock = java_lang_Class::init_lock(java_mirror());
 412   // Prevent reordering with any access of initialization state
 413   OrderAccess::loadload();
 414   assert((oop)lock != NULL || !is_not_initialized(), // initialized or in_error state
 415          "only fully initialized state can have a null lock");
 416   return lock;
 417 }
 418 
 419 // Set the initialization lock to null so the object can be GC'ed.  Any racing
 420 // threads to get this lock will see a null lock and will not lock.
 421 // That's okay because they all check for initialized state after getting
 422 // the lock and return.
 423 void InstanceKlass::fence_and_clear_init_lock() {
 424   // make sure previous stores are all done, notably the init_state.
 425   OrderAccess::storestore();
 426   java_lang_Class::set_init_lock(java_mirror(), NULL);
 427   assert(!is_not_initialized(), "class must be initialized now");
 428 }
 429 
 430 void InstanceKlass::eager_initialize_impl(instanceKlassHandle this_k) {
 431   EXCEPTION_MARK;
 432   oop init_lock = this_k->init_lock();
 433   ObjectLocker ol(init_lock, THREAD, init_lock != NULL);
 434 
 435   // abort if someone beat us to the initialization
 436   if (!this_k->is_not_initialized()) return;  // note: not equivalent to is_initialized()
 437 
 438   ClassState old_state = this_k->init_state();
 439   link_class_impl(this_k, true, THREAD);
 440   if (HAS_PENDING_EXCEPTION) {
 441     CLEAR_PENDING_EXCEPTION;
 442     // Abort if linking the class throws an exception.
 443 
 444     // Use a test to avoid redundantly resetting the state if there's
 445     // no change.  Set_init_state() asserts that state changes make
 446     // progress, whereas here we might just be spinning in place.
 447     if( old_state != this_k->_init_state )
 448       this_k->set_init_state (old_state);
 449   } else {
 450     // linking successfull, mark class as initialized
 451     this_k->set_init_state (fully_initialized);
 452     this_k->fence_and_clear_init_lock();
 453     // trace
 454     if (log_is_enabled(Info, classinit)) {
 455       ResourceMark rm(THREAD);
 456       log_info(classinit)("[Initialized %s without side effects]", this_k->external_name());
 457     }
 458   }
 459 }
 460 
 461 
 462 // See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization
 463 // process. The step comments refers to the procedure described in that section.
 464 // Note: implementation moved to static method to expose the this pointer.
 465 void InstanceKlass::initialize(TRAPS) {
 466   if (this->should_be_initialized()) {
 467     HandleMark hm(THREAD);
 468     instanceKlassHandle this_k(THREAD, this);
 469     initialize_impl(this_k, CHECK);
 470     // Note: at this point the class may be initialized
 471     //       OR it may be in the state of being initialized
 472     //       in case of recursive initialization!
 473   } else {
 474     assert(is_initialized(), "sanity check");
 475   }
 476 }
 477 
 478 
 479 bool InstanceKlass::verify_code(
 480     instanceKlassHandle this_k, bool throw_verifyerror, TRAPS) {
 481   // 1) Verify the bytecodes
 482   Verifier::Mode mode =
 483     throw_verifyerror ? Verifier::ThrowException : Verifier::NoException;
 484   return Verifier::verify(this_k, mode, this_k->should_verify_class(), THREAD);
 485 }
 486 
 487 
 488 // Used exclusively by the shared spaces dump mechanism to prevent
 489 // classes mapped into the shared regions in new VMs from appearing linked.
 490 
 491 void InstanceKlass::unlink_class() {
 492   assert(is_linked(), "must be linked");
 493   _init_state = loaded;
 494 }
 495 
 496 void InstanceKlass::link_class(TRAPS) {
 497   assert(is_loaded(), "must be loaded");
 498   if (!is_linked()) {
 499     HandleMark hm(THREAD);
 500     instanceKlassHandle this_k(THREAD, this);
 501     link_class_impl(this_k, true, CHECK);
 502   }
 503 }
 504 
 505 // Called to verify that a class can link during initialization, without
 506 // throwing a VerifyError.
 507 bool InstanceKlass::link_class_or_fail(TRAPS) {
 508   assert(is_loaded(), "must be loaded");
 509   if (!is_linked()) {
 510     HandleMark hm(THREAD);
 511     instanceKlassHandle this_k(THREAD, this);
 512     link_class_impl(this_k, false, CHECK_false);
 513   }
 514   return is_linked();
 515 }
 516 
 517 bool InstanceKlass::link_class_impl(
 518     instanceKlassHandle this_k, bool throw_verifyerror, TRAPS) {
 519   // check for error state
 520   if (this_k->is_in_error_state()) {
 521     ResourceMark rm(THREAD);
 522     THROW_MSG_(vmSymbols::java_lang_NoClassDefFoundError(),
 523                this_k->external_name(), false);
 524   }
 525   // return if already verified
 526   if (this_k->is_linked()) {
 527     return true;
 528   }
 529 
 530   // Timing
 531   // timer handles recursion
 532   assert(THREAD->is_Java_thread(), "non-JavaThread in link_class_impl");
 533   JavaThread* jt = (JavaThread*)THREAD;
 534 
 535   // link super class before linking this class
 536   instanceKlassHandle super(THREAD, this_k->super());
 537   if (super.not_null()) {
 538     if (super->is_interface()) {  // check if super class is an interface
 539       ResourceMark rm(THREAD);
 540       Exceptions::fthrow(
 541         THREAD_AND_LOCATION,
 542         vmSymbols::java_lang_IncompatibleClassChangeError(),
 543         "class %s has interface %s as super class",
 544         this_k->external_name(),
 545         super->external_name()
 546       );
 547       return false;
 548     }
 549 
 550     link_class_impl(super, throw_verifyerror, CHECK_false);
 551   }
 552 
 553   // link all interfaces implemented by this class before linking this class
 554   Array<Klass*>* interfaces = this_k->local_interfaces();
 555   int num_interfaces = interfaces->length();
 556   for (int index = 0; index < num_interfaces; index++) {
 557     HandleMark hm(THREAD);
 558     instanceKlassHandle ih(THREAD, interfaces->at(index));
 559     link_class_impl(ih, throw_verifyerror, CHECK_false);
 560   }
 561 
 562   // in case the class is linked in the process of linking its superclasses
 563   if (this_k->is_linked()) {
 564     return true;
 565   }
 566 
 567   // trace only the link time for this klass that includes
 568   // the verification time
 569   PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(),
 570                              ClassLoader::perf_class_link_selftime(),
 571                              ClassLoader::perf_classes_linked(),
 572                              jt->get_thread_stat()->perf_recursion_counts_addr(),
 573                              jt->get_thread_stat()->perf_timers_addr(),
 574                              PerfClassTraceTime::CLASS_LINK);
 575 
 576   // verification & rewriting
 577   {
 578     oop init_lock = this_k->init_lock();
 579     ObjectLocker ol(init_lock, THREAD, init_lock != NULL);
 580     // rewritten will have been set if loader constraint error found
 581     // on an earlier link attempt
 582     // don't verify or rewrite if already rewritten
 583 
 584     if (!this_k->is_linked()) {
 585       if (!this_k->is_rewritten()) {
 586         {
 587           bool verify_ok = verify_code(this_k, throw_verifyerror, THREAD);
 588           if (!verify_ok) {
 589             return false;
 590           }
 591         }
 592 
 593         // Just in case a side-effect of verify linked this class already
 594         // (which can sometimes happen since the verifier loads classes
 595         // using custom class loaders, which are free to initialize things)
 596         if (this_k->is_linked()) {
 597           return true;
 598         }
 599 
 600         // also sets rewritten
 601         this_k->rewrite_class(CHECK_false);
 602       }
 603 
 604       // relocate jsrs and link methods after they are all rewritten
 605       this_k->link_methods(CHECK_false);
 606 
 607       // Initialize the vtable and interface table after
 608       // methods have been rewritten since rewrite may
 609       // fabricate new Method*s.
 610       // also does loader constraint checking
 611       if (!this_k()->is_shared()) {
 612         ResourceMark rm(THREAD);
 613         this_k->vtable()->initialize_vtable(true, CHECK_false);
 614         this_k->itable()->initialize_itable(true, CHECK_false);
 615       }
 616 #ifdef ASSERT
 617       else {
 618         ResourceMark rm(THREAD);
 619         this_k->vtable()->verify(tty, true);
 620         // In case itable verification is ever added.
 621         // this_k->itable()->verify(tty, true);
 622       }
 623 #endif
 624       this_k->set_init_state(linked);
 625       if (JvmtiExport::should_post_class_prepare()) {
 626         Thread *thread = THREAD;
 627         assert(thread->is_Java_thread(), "thread->is_Java_thread()");
 628         JvmtiExport::post_class_prepare((JavaThread *) thread, this_k());
 629       }
 630     }
 631   }
 632   return true;
 633 }
 634 
 635 
 636 // Rewrite the byte codes of all of the methods of a class.
 637 // The rewriter must be called exactly once. Rewriting must happen after
 638 // verification but before the first method of the class is executed.
 639 void InstanceKlass::rewrite_class(TRAPS) {
 640   assert(is_loaded(), "must be loaded");
 641   instanceKlassHandle this_k(THREAD, this);
 642   if (this_k->is_rewritten()) {
 643     assert(this_k()->is_shared(), "rewriting an unshared class?");
 644     return;
 645   }
 646   Rewriter::rewrite(this_k, CHECK);
 647   this_k->set_rewritten();
 648 }
 649 
 650 // Now relocate and link method entry points after class is rewritten.
 651 // This is outside is_rewritten flag. In case of an exception, it can be
 652 // executed more than once.
 653 void InstanceKlass::link_methods(TRAPS) {
 654   int len = methods()->length();
 655   for (int i = len-1; i >= 0; i--) {
 656     methodHandle m(THREAD, methods()->at(i));
 657 
 658     // Set up method entry points for compiler and interpreter    .
 659     m->link_method(m, CHECK);
 660   }
 661 }
 662 
 663 // Eagerly initialize superinterfaces that declare default methods (concrete instance: any access)
 664 void InstanceKlass::initialize_super_interfaces(instanceKlassHandle this_k, TRAPS) {
 665   if (this_k->has_default_methods()) {
 666     for (int i = 0; i < this_k->local_interfaces()->length(); ++i) {
 667       Klass* iface = this_k->local_interfaces()->at(i);
 668       InstanceKlass* ik = InstanceKlass::cast(iface);
 669       if (ik->should_be_initialized()) {
 670         if (ik->has_default_methods()) {
 671           ik->initialize_super_interfaces(ik, THREAD);
 672         }
 673         // Only initialize() interfaces that "declare" concrete methods.
 674         // has_default_methods drives searching superinterfaces since it
 675         // means has_default_methods in its superinterface hierarchy
 676         if (!HAS_PENDING_EXCEPTION && ik->declares_default_methods()) {
 677           ik->initialize(THREAD);
 678         }
 679         if (HAS_PENDING_EXCEPTION) {
 680           Handle e(THREAD, PENDING_EXCEPTION);
 681           CLEAR_PENDING_EXCEPTION;
 682           {
 683             EXCEPTION_MARK;
 684             // Locks object, set state, and notify all waiting threads
 685             this_k->set_initialization_state_and_notify(
 686                 initialization_error, THREAD);
 687 
 688             // ignore any exception thrown, superclass initialization error is
 689             // thrown below
 690             CLEAR_PENDING_EXCEPTION;
 691           }
 692           THROW_OOP(e());
 693         }
 694       }
 695     }
 696   }
 697 }
 698 
 699 void InstanceKlass::initialize_impl(instanceKlassHandle this_k, TRAPS) {
 700   // Make sure klass is linked (verified) before initialization
 701   // A class could already be verified, since it has been reflected upon.
 702   this_k->link_class(CHECK);
 703 
 704   DTRACE_CLASSINIT_PROBE(required, this_k(), -1);
 705 
 706   bool wait = false;
 707 
 708   // refer to the JVM book page 47 for description of steps
 709   // Step 1
 710   {
 711     oop init_lock = this_k->init_lock();
 712     ObjectLocker ol(init_lock, THREAD, init_lock != NULL);
 713 
 714     Thread *self = THREAD; // it's passed the current thread
 715 
 716     // Step 2
 717     // If we were to use wait() instead of waitInterruptibly() then
 718     // we might end up throwing IE from link/symbol resolution sites
 719     // that aren't expected to throw.  This would wreak havoc.  See 6320309.
 720     while(this_k->is_being_initialized() && !this_k->is_reentrant_initialization(self)) {
 721         wait = true;
 722       ol.waitUninterruptibly(CHECK);
 723     }
 724 
 725     // Step 3
 726     if (this_k->is_being_initialized() && this_k->is_reentrant_initialization(self)) {
 727       DTRACE_CLASSINIT_PROBE_WAIT(recursive, this_k(), -1,wait);
 728       return;
 729     }
 730 
 731     // Step 4
 732     if (this_k->is_initialized()) {
 733       DTRACE_CLASSINIT_PROBE_WAIT(concurrent, this_k(), -1,wait);
 734       return;
 735     }
 736 
 737     // Step 5
 738     if (this_k->is_in_error_state()) {
 739       DTRACE_CLASSINIT_PROBE_WAIT(erroneous, this_k(), -1,wait);
 740       ResourceMark rm(THREAD);
 741       const char* desc = "Could not initialize class ";
 742       const char* className = this_k->external_name();
 743       size_t msglen = strlen(desc) + strlen(className) + 1;
 744       char* message = NEW_RESOURCE_ARRAY(char, msglen);
 745       if (NULL == message) {
 746         // Out of memory: can't create detailed error message
 747         THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), className);
 748       } else {
 749         jio_snprintf(message, msglen, "%s%s", desc, className);
 750         THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), message);
 751       }
 752     }
 753 
 754     // Step 6
 755     this_k->set_init_state(being_initialized);
 756     this_k->set_init_thread(self);
 757   }
 758 
 759   // Step 7
 760   Klass* super_klass = this_k->super();
 761   if (super_klass != NULL && !this_k->is_interface() && super_klass->should_be_initialized()) {
 762     super_klass->initialize(THREAD);
 763 
 764     if (HAS_PENDING_EXCEPTION) {
 765       Handle e(THREAD, PENDING_EXCEPTION);
 766       CLEAR_PENDING_EXCEPTION;
 767       {
 768         EXCEPTION_MARK;
 769         this_k->set_initialization_state_and_notify(initialization_error, THREAD); // Locks object, set state, and notify all waiting threads
 770         CLEAR_PENDING_EXCEPTION;   // ignore any exception thrown, superclass initialization error is thrown below
 771       }
 772       DTRACE_CLASSINIT_PROBE_WAIT(super__failed, this_k(), -1,wait);
 773       THROW_OOP(e());
 774     }
 775   }
 776 
 777   // If C is an interface that declares a non-abstract, non-static method,
 778   // the initialization of a class (not an interface) that implements C directly or
 779   // indirectly.
 780   // Recursively initialize any superinterfaces that declare default methods
 781   // Only need to recurse if has_default_methods which includes declaring and
 782   // inheriting default methods
 783   if (!this_k->is_interface() && this_k->has_default_methods()) {
 784     this_k->initialize_super_interfaces(this_k, CHECK);
 785   }
 786 
 787   // Step 8
 788   {
 789     assert(THREAD->is_Java_thread(), "non-JavaThread in initialize_impl");
 790     JavaThread* jt = (JavaThread*)THREAD;
 791     DTRACE_CLASSINIT_PROBE_WAIT(clinit, this_k(), -1,wait);
 792     // Timer includes any side effects of class initialization (resolution,
 793     // etc), but not recursive entry into call_class_initializer().
 794     PerfClassTraceTime timer(ClassLoader::perf_class_init_time(),
 795                              ClassLoader::perf_class_init_selftime(),
 796                              ClassLoader::perf_classes_inited(),
 797                              jt->get_thread_stat()->perf_recursion_counts_addr(),
 798                              jt->get_thread_stat()->perf_timers_addr(),
 799                              PerfClassTraceTime::CLASS_CLINIT);
 800     this_k->call_class_initializer(THREAD);
 801   }
 802 
 803   // Step 9
 804   if (!HAS_PENDING_EXCEPTION) {
 805     this_k->set_initialization_state_and_notify(fully_initialized, CHECK);
 806     { ResourceMark rm(THREAD);
 807       debug_only(this_k->vtable()->verify(tty, true);)
 808     }
 809   }
 810   else {
 811     // Step 10 and 11
 812     Handle e(THREAD, PENDING_EXCEPTION);
 813     CLEAR_PENDING_EXCEPTION;
 814     // JVMTI has already reported the pending exception
 815     // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
 816     JvmtiExport::clear_detected_exception((JavaThread*)THREAD);
 817     {
 818       EXCEPTION_MARK;
 819       this_k->set_initialization_state_and_notify(initialization_error, THREAD);
 820       CLEAR_PENDING_EXCEPTION;   // ignore any exception thrown, class initialization error is thrown below
 821       // JVMTI has already reported the pending exception
 822       // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
 823       JvmtiExport::clear_detected_exception((JavaThread*)THREAD);
 824     }
 825     DTRACE_CLASSINIT_PROBE_WAIT(error, this_k(), -1,wait);
 826     if (e->is_a(SystemDictionary::Error_klass())) {
 827       THROW_OOP(e());
 828     } else {
 829       JavaCallArguments args(e);
 830       THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(),
 831                 vmSymbols::throwable_void_signature(),
 832                 &args);
 833     }
 834   }
 835   DTRACE_CLASSINIT_PROBE_WAIT(end, this_k(), -1,wait);
 836 }
 837 
 838 
 839 // Note: implementation moved to static method to expose the this pointer.
 840 void InstanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) {
 841   instanceKlassHandle kh(THREAD, this);
 842   set_initialization_state_and_notify_impl(kh, state, CHECK);
 843 }
 844 
 845 void InstanceKlass::set_initialization_state_and_notify_impl(instanceKlassHandle this_k, ClassState state, TRAPS) {
 846   oop init_lock = this_k->init_lock();
 847   ObjectLocker ol(init_lock, THREAD, init_lock != NULL);
 848   this_k->set_init_state(state);
 849   this_k->fence_and_clear_init_lock();
 850   ol.notify_all(CHECK);
 851 }
 852 
 853 // The embedded _implementor field can only record one implementor.
 854 // When there are more than one implementors, the _implementor field
 855 // is set to the interface Klass* itself. Following are the possible
 856 // values for the _implementor field:
 857 //   NULL                  - no implementor
 858 //   implementor Klass*    - one implementor
 859 //   self                  - more than one implementor
 860 //
 861 // The _implementor field only exists for interfaces.
 862 void InstanceKlass::add_implementor(Klass* k) {
 863   assert(Compile_lock->owned_by_self(), "");
 864   assert(is_interface(), "not interface");
 865   // Filter out my subinterfaces.
 866   // (Note: Interfaces are never on the subklass list.)
 867   if (InstanceKlass::cast(k)->is_interface()) return;
 868 
 869   // Filter out subclasses whose supers already implement me.
 870   // (Note: CHA must walk subclasses of direct implementors
 871   // in order to locate indirect implementors.)
 872   Klass* sk = k->super();
 873   if (sk != NULL && InstanceKlass::cast(sk)->implements_interface(this))
 874     // We only need to check one immediate superclass, since the
 875     // implements_interface query looks at transitive_interfaces.
 876     // Any supers of the super have the same (or fewer) transitive_interfaces.
 877     return;
 878 
 879   Klass* ik = implementor();
 880   if (ik == NULL) {
 881     set_implementor(k);
 882   } else if (ik != this) {
 883     // There is already an implementor. Use itself as an indicator of
 884     // more than one implementors.
 885     set_implementor(this);
 886   }
 887 
 888   // The implementor also implements the transitive_interfaces
 889   for (int index = 0; index < local_interfaces()->length(); index++) {
 890     InstanceKlass::cast(local_interfaces()->at(index))->add_implementor(k);
 891   }
 892 }
 893 
 894 void InstanceKlass::init_implementor() {
 895   if (is_interface()) {
 896     set_implementor(NULL);
 897   }
 898 }
 899 
 900 
 901 void InstanceKlass::process_interfaces(Thread *thread) {
 902   // link this class into the implementors list of every interface it implements
 903   for (int i = local_interfaces()->length() - 1; i >= 0; i--) {
 904     assert(local_interfaces()->at(i)->is_klass(), "must be a klass");
 905     InstanceKlass* interf = InstanceKlass::cast(local_interfaces()->at(i));
 906     assert(interf->is_interface(), "expected interface");
 907     interf->add_implementor(this);
 908   }
 909 }
 910 
 911 bool InstanceKlass::can_be_primary_super_slow() const {
 912   if (is_interface())
 913     return false;
 914   else
 915     return Klass::can_be_primary_super_slow();
 916 }
 917 
 918 GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots) {
 919   // The secondaries are the implemented interfaces.
 920   Array<Klass*>* interfaces = transitive_interfaces();
 921   int num_secondaries = num_extra_slots + interfaces->length();
 922   if (num_secondaries == 0) {
 923     // Must share this for correct bootstrapping!
 924     set_secondary_supers(Universe::the_empty_klass_array());
 925     return NULL;
 926   } else if (num_extra_slots == 0) {
 927     // The secondary super list is exactly the same as the transitive interfaces.
 928     // Redefine classes has to be careful not to delete this!
 929     set_secondary_supers(interfaces);
 930     return NULL;
 931   } else {
 932     // Copy transitive interfaces to a temporary growable array to be constructed
 933     // into the secondary super list with extra slots.
 934     GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length());
 935     for (int i = 0; i < interfaces->length(); i++) {
 936       secondaries->push(interfaces->at(i));
 937     }
 938     return secondaries;
 939   }
 940 }
 941 
 942 bool InstanceKlass::compute_is_subtype_of(Klass* k) {
 943   if (k->is_interface()) {
 944     return implements_interface(k);
 945   } else {
 946     return Klass::compute_is_subtype_of(k);
 947   }
 948 }
 949 
 950 bool InstanceKlass::implements_interface(Klass* k) const {
 951   if (this == k) return true;
 952   assert(k->is_interface(), "should be an interface class");
 953   for (int i = 0; i < transitive_interfaces()->length(); i++) {
 954     if (transitive_interfaces()->at(i) == k) {
 955       return true;
 956     }
 957   }
 958   return false;
 959 }
 960 
 961 bool InstanceKlass::is_same_or_direct_interface(Klass *k) const {
 962   // Verify direct super interface
 963   if (this == k) return true;
 964   assert(k->is_interface(), "should be an interface class");
 965   for (int i = 0; i < local_interfaces()->length(); i++) {
 966     if (local_interfaces()->at(i) == k) {
 967       return true;
 968     }
 969   }
 970   return false;
 971 }
 972 
 973 objArrayOop InstanceKlass::allocate_objArray(int n, int length, TRAPS) {
 974   if (length < 0) THROW_0(vmSymbols::java_lang_NegativeArraySizeException());
 975   if (length > arrayOopDesc::max_array_length(T_OBJECT)) {
 976     report_java_out_of_memory("Requested array size exceeds VM limit");
 977     JvmtiExport::post_array_size_exhausted();
 978     THROW_OOP_0(Universe::out_of_memory_error_array_size());
 979   }
 980   int size = objArrayOopDesc::object_size(length);
 981   Klass* ak = array_klass(n, CHECK_NULL);
 982   KlassHandle h_ak (THREAD, ak);
 983   objArrayOop o =
 984     (objArrayOop)CollectedHeap::array_allocate(h_ak, size, length, CHECK_NULL);
 985   return o;
 986 }
 987 
 988 instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) {
 989   if (TraceFinalizerRegistration) {
 990     tty->print("Registered ");
 991     i->print_value_on(tty);
 992     tty->print_cr(" (" INTPTR_FORMAT ") as finalizable", p2i(i));
 993   }
 994   instanceHandle h_i(THREAD, i);
 995   // Pass the handle as argument, JavaCalls::call expects oop as jobjects
 996   JavaValue result(T_VOID);
 997   JavaCallArguments args(h_i);
 998   methodHandle mh (THREAD, Universe::finalizer_register_method());
 999   JavaCalls::call(&result, mh, &args, CHECK_NULL);
1000   return h_i();
1001 }
1002 
1003 instanceOop InstanceKlass::allocate_instance(TRAPS) {
1004   bool has_finalizer_flag = has_finalizer(); // Query before possible GC
1005   int size = size_helper();  // Query before forming handle.
1006 
1007   KlassHandle h_k(THREAD, this);
1008 
1009   instanceOop i;
1010 
1011   i = (instanceOop)CollectedHeap::obj_allocate(h_k, size, CHECK_NULL);
1012   if (has_finalizer_flag && !RegisterFinalizersAtInit) {
1013     i = register_finalizer(i, CHECK_NULL);
1014   }
1015   return i;
1016 }
1017 
1018 void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) {
1019   if (is_interface() || is_abstract()) {
1020     ResourceMark rm(THREAD);
1021     THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
1022               : vmSymbols::java_lang_InstantiationException(), external_name());
1023   }
1024   if (this == SystemDictionary::Class_klass()) {
1025     ResourceMark rm(THREAD);
1026     THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError()
1027               : vmSymbols::java_lang_IllegalAccessException(), external_name());
1028   }
1029 }
1030 
1031 Klass* InstanceKlass::array_klass_impl(bool or_null, int n, TRAPS) {
1032   instanceKlassHandle this_k(THREAD, this);
1033   return array_klass_impl(this_k, or_null, n, THREAD);
1034 }
1035 
1036 Klass* InstanceKlass::array_klass_impl(instanceKlassHandle this_k, bool or_null, int n, TRAPS) {
1037   if (this_k->array_klasses() == NULL) {
1038     if (or_null) return NULL;
1039 
1040     ResourceMark rm;
1041     JavaThread *jt = (JavaThread *)THREAD;
1042     {
1043       // Atomic creation of array_klasses
1044       MutexLocker mc(Compile_lock, THREAD);   // for vtables
1045       MutexLocker ma(MultiArray_lock, THREAD);
1046 
1047       // Check if update has already taken place
1048       if (this_k->array_klasses() == NULL) {
1049         Klass*    k = ObjArrayKlass::allocate_objArray_klass(this_k->class_loader_data(), 1, this_k, CHECK_NULL);
1050         this_k->set_array_klasses(k);
1051       }
1052     }
1053   }
1054   // _this will always be set at this point
1055   ObjArrayKlass* oak = (ObjArrayKlass*)this_k->array_klasses();
1056   if (or_null) {
1057     return oak->array_klass_or_null(n);
1058   }
1059   return oak->array_klass(n, THREAD);
1060 }
1061 
1062 Klass* InstanceKlass::array_klass_impl(bool or_null, TRAPS) {
1063   return array_klass_impl(or_null, 1, THREAD);
1064 }
1065 
1066 void InstanceKlass::call_class_initializer(TRAPS) {
1067   instanceKlassHandle ik (THREAD, this);
1068   call_class_initializer_impl(ik, THREAD);
1069 }
1070 
1071 static int call_class_initializer_impl_counter = 0;   // for debugging
1072 
1073 Method* InstanceKlass::class_initializer() {
1074   Method* clinit = find_method(
1075       vmSymbols::class_initializer_name(), vmSymbols::void_method_signature());
1076   if (clinit != NULL && clinit->has_valid_initializer_flags()) {
1077     return clinit;
1078   }
1079   return NULL;
1080 }
1081 
1082 void InstanceKlass::call_class_initializer_impl(instanceKlassHandle this_k, TRAPS) {
1083   if (ReplayCompiles &&
1084       (ReplaySuppressInitializers == 1 ||
1085        ReplaySuppressInitializers >= 2 && this_k->class_loader() != NULL)) {
1086     // Hide the existence of the initializer for the purpose of replaying the compile
1087     return;
1088   }
1089 
1090   methodHandle h_method(THREAD, this_k->class_initializer());
1091   assert(!this_k->is_initialized(), "we cannot initialize twice");
1092   if (log_is_enabled(Info, classinit)) {
1093     ResourceMark rm;
1094     outputStream* log = LogHandle(classinit)::info_stream();
1095     log->print("%d Initializing ", call_class_initializer_impl_counter++);
1096     this_k->name()->print_value_on(log);
1097     log->print_cr("%s (" INTPTR_FORMAT ")", h_method() == NULL ? "(no method)" : "", p2i(this_k()));
1098   }
1099   if (h_method() != NULL) {
1100     JavaCallArguments args; // No arguments
1101     JavaValue result(T_VOID);
1102     JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args)
1103   }
1104 }
1105 
1106 
1107 void InstanceKlass::mask_for(const methodHandle& method, int bci,
1108   InterpreterOopMap* entry_for) {
1109   // Dirty read, then double-check under a lock.
1110   if (_oop_map_cache == NULL) {
1111     // Otherwise, allocate a new one.
1112     MutexLocker x(OopMapCacheAlloc_lock);
1113     // First time use. Allocate a cache in C heap
1114     if (_oop_map_cache == NULL) {
1115       // Release stores from OopMapCache constructor before assignment
1116       // to _oop_map_cache. C++ compilers on ppc do not emit the
1117       // required memory barrier only because of the volatile
1118       // qualifier of _oop_map_cache.
1119       OrderAccess::release_store_ptr(&_oop_map_cache, new OopMapCache());
1120     }
1121   }
1122   // _oop_map_cache is constant after init; lookup below does is own locking.
1123   _oop_map_cache->lookup(method, bci, entry_for);
1124 }
1125 
1126 
1127 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1128   for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1129     Symbol* f_name = fs.name();
1130     Symbol* f_sig  = fs.signature();
1131     if (f_name == name && f_sig == sig) {
1132       fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1133       return true;
1134     }
1135   }
1136   return false;
1137 }
1138 
1139 
1140 Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1141   const int n = local_interfaces()->length();
1142   for (int i = 0; i < n; i++) {
1143     Klass* intf1 = local_interfaces()->at(i);
1144     assert(intf1->is_interface(), "just checking type");
1145     // search for field in current interface
1146     if (InstanceKlass::cast(intf1)->find_local_field(name, sig, fd)) {
1147       assert(fd->is_static(), "interface field must be static");
1148       return intf1;
1149     }
1150     // search for field in direct superinterfaces
1151     Klass* intf2 = InstanceKlass::cast(intf1)->find_interface_field(name, sig, fd);
1152     if (intf2 != NULL) return intf2;
1153   }
1154   // otherwise field lookup fails
1155   return NULL;
1156 }
1157 
1158 
1159 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1160   // search order according to newest JVM spec (5.4.3.2, p.167).
1161   // 1) search for field in current klass
1162   if (find_local_field(name, sig, fd)) {
1163     return const_cast<InstanceKlass*>(this);
1164   }
1165   // 2) search for field recursively in direct superinterfaces
1166   { Klass* intf = find_interface_field(name, sig, fd);
1167     if (intf != NULL) return intf;
1168   }
1169   // 3) apply field lookup recursively if superclass exists
1170   { Klass* supr = super();
1171     if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, fd);
1172   }
1173   // 4) otherwise field lookup fails
1174   return NULL;
1175 }
1176 
1177 
1178 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const {
1179   // search order according to newest JVM spec (5.4.3.2, p.167).
1180   // 1) search for field in current klass
1181   if (find_local_field(name, sig, fd)) {
1182     if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this);
1183   }
1184   // 2) search for field recursively in direct superinterfaces
1185   if (is_static) {
1186     Klass* intf = find_interface_field(name, sig, fd);
1187     if (intf != NULL) return intf;
1188   }
1189   // 3) apply field lookup recursively if superclass exists
1190   { Klass* supr = super();
1191     if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, is_static, fd);
1192   }
1193   // 4) otherwise field lookup fails
1194   return NULL;
1195 }
1196 
1197 
1198 bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1199   for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1200     if (fs.offset() == offset) {
1201       fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1202       if (fd->is_static() == is_static) return true;
1203     }
1204   }
1205   return false;
1206 }
1207 
1208 
1209 bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1210   Klass* klass = const_cast<InstanceKlass*>(this);
1211   while (klass != NULL) {
1212     if (InstanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) {
1213       return true;
1214     }
1215     klass = klass->super();
1216   }
1217   return false;
1218 }
1219 
1220 
1221 void InstanceKlass::methods_do(void f(Method* method)) {
1222   // Methods aren't stable until they are loaded.  This can be read outside
1223   // a lock through the ClassLoaderData for profiling
1224   if (!is_loaded()) {
1225     return;
1226   }
1227 
1228   int len = methods()->length();
1229   for (int index = 0; index < len; index++) {
1230     Method* m = methods()->at(index);
1231     assert(m->is_method(), "must be method");
1232     f(m);
1233   }
1234 }
1235 
1236 
1237 void InstanceKlass::do_local_static_fields(FieldClosure* cl) {
1238   for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1239     if (fs.access_flags().is_static()) {
1240       fieldDescriptor& fd = fs.field_descriptor();
1241       cl->do_field(&fd);
1242     }
1243   }
1244 }
1245 
1246 
1247 void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle mirror, TRAPS) {
1248   instanceKlassHandle h_this(THREAD, this);
1249   do_local_static_fields_impl(h_this, f, mirror, CHECK);
1250 }
1251 
1252 
1253 void InstanceKlass::do_local_static_fields_impl(instanceKlassHandle this_k,
1254                              void f(fieldDescriptor* fd, Handle, TRAPS), Handle mirror, TRAPS) {
1255   for (JavaFieldStream fs(this_k()); !fs.done(); fs.next()) {
1256     if (fs.access_flags().is_static()) {
1257       fieldDescriptor& fd = fs.field_descriptor();
1258       f(&fd, mirror, CHECK);
1259     }
1260   }
1261 }
1262 
1263 
1264 static int compare_fields_by_offset(int* a, int* b) {
1265   return a[0] - b[0];
1266 }
1267 
1268 void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) {
1269   InstanceKlass* super = superklass();
1270   if (super != NULL) {
1271     super->do_nonstatic_fields(cl);
1272   }
1273   fieldDescriptor fd;
1274   int length = java_fields_count();
1275   // In DebugInfo nonstatic fields are sorted by offset.
1276   int* fields_sorted = NEW_C_HEAP_ARRAY(int, 2*(length+1), mtClass);
1277   int j = 0;
1278   for (int i = 0; i < length; i += 1) {
1279     fd.reinitialize(this, i);
1280     if (!fd.is_static()) {
1281       fields_sorted[j + 0] = fd.offset();
1282       fields_sorted[j + 1] = i;
1283       j += 2;
1284     }
1285   }
1286   if (j > 0) {
1287     length = j;
1288     // _sort_Fn is defined in growableArray.hpp.
1289     qsort(fields_sorted, length/2, 2*sizeof(int), (_sort_Fn)compare_fields_by_offset);
1290     for (int i = 0; i < length; i += 2) {
1291       fd.reinitialize(this, fields_sorted[i + 1]);
1292       assert(!fd.is_static() && fd.offset() == fields_sorted[i], "only nonstatic fields");
1293       cl->do_field(&fd);
1294     }
1295   }
1296   FREE_C_HEAP_ARRAY(int, fields_sorted);
1297 }
1298 
1299 
1300 void InstanceKlass::array_klasses_do(void f(Klass* k, TRAPS), TRAPS) {
1301   if (array_klasses() != NULL)
1302     ArrayKlass::cast(array_klasses())->array_klasses_do(f, THREAD);
1303 }
1304 
1305 void InstanceKlass::array_klasses_do(void f(Klass* k)) {
1306   if (array_klasses() != NULL)
1307     ArrayKlass::cast(array_klasses())->array_klasses_do(f);
1308 }
1309 
1310 #ifdef ASSERT
1311 static int linear_search(const Array<Method*>* methods,
1312                          const Symbol* name,
1313                          const Symbol* signature) {
1314   const int len = methods->length();
1315   for (int index = 0; index < len; index++) {
1316     const Method* const m = methods->at(index);
1317     assert(m->is_method(), "must be method");
1318     if (m->signature() == signature && m->name() == name) {
1319        return index;
1320     }
1321   }
1322   return -1;
1323 }
1324 #endif
1325 
1326 static int binary_search(const Array<Method*>* methods, const Symbol* name) {
1327   int len = methods->length();
1328   // methods are sorted, so do binary search
1329   int l = 0;
1330   int h = len - 1;
1331   while (l <= h) {
1332     int mid = (l + h) >> 1;
1333     Method* m = methods->at(mid);
1334     assert(m->is_method(), "must be method");
1335     int res = m->name()->fast_compare(name);
1336     if (res == 0) {
1337       return mid;
1338     } else if (res < 0) {
1339       l = mid + 1;
1340     } else {
1341       h = mid - 1;
1342     }
1343   }
1344   return -1;
1345 }
1346 
1347 // find_method looks up the name/signature in the local methods array
1348 Method* InstanceKlass::find_method(const Symbol* name,
1349                                    const Symbol* signature) const {
1350   return find_method_impl(name, signature, find_overpass, find_static, find_private);
1351 }
1352 
1353 Method* InstanceKlass::find_method_impl(const Symbol* name,
1354                                         const Symbol* signature,
1355                                         OverpassLookupMode overpass_mode,
1356                                         StaticLookupMode static_mode,
1357                                         PrivateLookupMode private_mode) const {
1358   return InstanceKlass::find_method_impl(methods(),
1359                                          name,
1360                                          signature,
1361                                          overpass_mode,
1362                                          static_mode,
1363                                          private_mode);
1364 }
1365 
1366 // find_instance_method looks up the name/signature in the local methods array
1367 // and skips over static methods
1368 Method* InstanceKlass::find_instance_method(const Array<Method*>* methods,
1369                                             const Symbol* name,
1370                                             const Symbol* signature) {
1371   Method* const meth = InstanceKlass::find_method_impl(methods,
1372                                                  name,
1373                                                  signature,
1374                                                  find_overpass,
1375                                                  skip_static,
1376                                                  find_private);
1377   assert(((meth == NULL) || !meth->is_static()),
1378     "find_instance_method should have skipped statics");
1379   return meth;
1380 }
1381 
1382 // find_instance_method looks up the name/signature in the local methods array
1383 // and skips over static methods
1384 Method* InstanceKlass::find_instance_method(const Symbol* name, const Symbol* signature) const {
1385   return InstanceKlass::find_instance_method(methods(), name, signature);
1386 }
1387 
1388 // Find looks up the name/signature in the local methods array
1389 // and filters on the overpass, static and private flags
1390 // This returns the first one found
1391 // note that the local methods array can have up to one overpass, one static
1392 // and one instance (private or not) with the same name/signature
1393 Method* InstanceKlass::find_local_method(const Symbol* name,
1394                                          const Symbol* signature,
1395                                          OverpassLookupMode overpass_mode,
1396                                          StaticLookupMode static_mode,
1397                                          PrivateLookupMode private_mode) const {
1398   return InstanceKlass::find_method_impl(methods(),
1399                                          name,
1400                                          signature,
1401                                          overpass_mode,
1402                                          static_mode,
1403                                          private_mode);
1404 }
1405 
1406 // Find looks up the name/signature in the local methods array
1407 // and filters on the overpass, static and private flags
1408 // This returns the first one found
1409 // note that the local methods array can have up to one overpass, one static
1410 // and one instance (private or not) with the same name/signature
1411 Method* InstanceKlass::find_local_method(const Array<Method*>* methods,
1412                                          const Symbol* name,
1413                                          const Symbol* signature,
1414                                          OverpassLookupMode overpass_mode,
1415                                          StaticLookupMode static_mode,
1416                                          PrivateLookupMode private_mode) {
1417   return InstanceKlass::find_method_impl(methods,
1418                                          name,
1419                                          signature,
1420                                          overpass_mode,
1421                                          static_mode,
1422                                          private_mode);
1423 }
1424 
1425 Method* InstanceKlass::find_method(const Array<Method*>* methods,
1426                                    const Symbol* name,
1427                                    const Symbol* signature) {
1428   return InstanceKlass::find_method_impl(methods,
1429                                          name,
1430                                          signature,
1431                                          find_overpass,
1432                                          find_static,
1433                                          find_private);
1434 }
1435 
1436 Method* InstanceKlass::find_method_impl(const Array<Method*>* methods,
1437                                         const Symbol* name,
1438                                         const Symbol* signature,
1439                                         OverpassLookupMode overpass_mode,
1440                                         StaticLookupMode static_mode,
1441                                         PrivateLookupMode private_mode) {
1442   int hit = find_method_index(methods, name, signature, overpass_mode, static_mode, private_mode);
1443   return hit >= 0 ? methods->at(hit): NULL;
1444 }
1445 
1446 // true if method matches signature and conforms to skipping_X conditions.
1447 static bool method_matches(const Method* m,
1448                            const Symbol* signature,
1449                            bool skipping_overpass,
1450                            bool skipping_static,
1451                            bool skipping_private) {
1452   return ((m->signature() == signature) &&
1453     (!skipping_overpass || !m->is_overpass()) &&
1454     (!skipping_static || !m->is_static()) &&
1455     (!skipping_private || !m->is_private()));
1456 }
1457 
1458 // Used directly for default_methods to find the index into the
1459 // default_vtable_indices, and indirectly by find_method
1460 // find_method_index looks in the local methods array to return the index
1461 // of the matching name/signature. If, overpass methods are being ignored,
1462 // the search continues to find a potential non-overpass match.  This capability
1463 // is important during method resolution to prefer a static method, for example,
1464 // over an overpass method.
1465 // There is the possibility in any _method's array to have the same name/signature
1466 // for a static method, an overpass method and a local instance method
1467 // To correctly catch a given method, the search criteria may need
1468 // to explicitly skip the other two. For local instance methods, it
1469 // is often necessary to skip private methods
1470 int InstanceKlass::find_method_index(const Array<Method*>* methods,
1471                                      const Symbol* name,
1472                                      const Symbol* signature,
1473                                      OverpassLookupMode overpass_mode,
1474                                      StaticLookupMode static_mode,
1475                                      PrivateLookupMode private_mode) {
1476   const bool skipping_overpass = (overpass_mode == skip_overpass);
1477   const bool skipping_static = (static_mode == skip_static);
1478   const bool skipping_private = (private_mode == skip_private);
1479   const int hit = binary_search(methods, name);
1480   if (hit != -1) {
1481     const Method* const m = methods->at(hit);
1482 
1483     // Do linear search to find matching signature.  First, quick check
1484     // for common case, ignoring overpasses if requested.
1485     if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1486           return hit;
1487     }
1488 
1489     // search downwards through overloaded methods
1490     int i;
1491     for (i = hit - 1; i >= 0; --i) {
1492         const Method* const m = methods->at(i);
1493         assert(m->is_method(), "must be method");
1494         if (m->name() != name) {
1495           break;
1496         }
1497         if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1498           return i;
1499         }
1500     }
1501     // search upwards
1502     for (i = hit + 1; i < methods->length(); ++i) {
1503         const Method* const m = methods->at(i);
1504         assert(m->is_method(), "must be method");
1505         if (m->name() != name) {
1506           break;
1507         }
1508         if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1509           return i;
1510         }
1511     }
1512     // not found
1513 #ifdef ASSERT
1514     const int index = (skipping_overpass || skipping_static || skipping_private) ? -1 :
1515       linear_search(methods, name, signature);
1516     assert(-1 == index, "binary search should have found entry %d", index);
1517 #endif
1518   }
1519   return -1;
1520 }
1521 
1522 int InstanceKlass::find_method_by_name(const Symbol* name, int* end) const {
1523   return find_method_by_name(methods(), name, end);
1524 }
1525 
1526 int InstanceKlass::find_method_by_name(const Array<Method*>* methods,
1527                                        const Symbol* name,
1528                                        int* end_ptr) {
1529   assert(end_ptr != NULL, "just checking");
1530   int start = binary_search(methods, name);
1531   int end = start + 1;
1532   if (start != -1) {
1533     while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start;
1534     while (end < methods->length() && (methods->at(end))->name() == name) ++end;
1535     *end_ptr = end;
1536     return start;
1537   }
1538   return -1;
1539 }
1540 
1541 // uncached_lookup_method searches both the local class methods array and all
1542 // superclasses methods arrays, skipping any overpass methods in superclasses.
1543 Method* InstanceKlass::uncached_lookup_method(const Symbol* name,
1544                                               const Symbol* signature,
1545                                               OverpassLookupMode overpass_mode) const {
1546   OverpassLookupMode overpass_local_mode = overpass_mode;
1547   const Klass* klass = this;
1548   while (klass != NULL) {
1549     Method* const method = InstanceKlass::cast(klass)->find_method_impl(name,
1550                                                                         signature,
1551                                                                         overpass_local_mode,
1552                                                                         find_static,
1553                                                                         find_private);
1554     if (method != NULL) {
1555       return method;
1556     }
1557     klass = klass->super();
1558     overpass_local_mode = skip_overpass;   // Always ignore overpass methods in superclasses
1559   }
1560   return NULL;
1561 }
1562 
1563 #ifdef ASSERT
1564 // search through class hierarchy and return true if this class or
1565 // one of the superclasses was redefined
1566 bool InstanceKlass::has_redefined_this_or_super() const {
1567   const Klass* klass = this;
1568   while (klass != NULL) {
1569     if (InstanceKlass::cast(klass)->has_been_redefined()) {
1570       return true;
1571     }
1572     klass = klass->super();
1573   }
1574   return false;
1575 }
1576 #endif
1577 
1578 // lookup a method in the default methods list then in all transitive interfaces
1579 // Do NOT return private or static methods
1580 Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name,
1581                                                          Symbol* signature) const {
1582   Method* m = NULL;
1583   if (default_methods() != NULL) {
1584     m = find_method(default_methods(), name, signature);
1585   }
1586   // Look up interfaces
1587   if (m == NULL) {
1588     m = lookup_method_in_all_interfaces(name, signature, find_defaults);
1589   }
1590   return m;
1591 }
1592 
1593 // lookup a method in all the interfaces that this class implements
1594 // Do NOT return private or static methods, new in JDK8 which are not externally visible
1595 // They should only be found in the initial InterfaceMethodRef
1596 Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name,
1597                                                        Symbol* signature,
1598                                                        DefaultsLookupMode defaults_mode) const {
1599   Array<Klass*>* all_ifs = transitive_interfaces();
1600   int num_ifs = all_ifs->length();
1601   InstanceKlass *ik = NULL;
1602   for (int i = 0; i < num_ifs; i++) {
1603     ik = InstanceKlass::cast(all_ifs->at(i));
1604     Method* m = ik->lookup_method(name, signature);
1605     if (m != NULL && m->is_public() && !m->is_static() &&
1606         ((defaults_mode != skip_defaults) || !m->is_default_method())) {
1607       return m;
1608     }
1609   }
1610   return NULL;
1611 }
1612 
1613 /* jni_id_for_impl for jfieldIds only */
1614 JNIid* InstanceKlass::jni_id_for_impl(instanceKlassHandle this_k, int offset) {
1615   MutexLocker ml(JfieldIdCreation_lock);
1616   // Retry lookup after we got the lock
1617   JNIid* probe = this_k->jni_ids() == NULL ? NULL : this_k->jni_ids()->find(offset);
1618   if (probe == NULL) {
1619     // Slow case, allocate new static field identifier
1620     probe = new JNIid(this_k(), offset, this_k->jni_ids());
1621     this_k->set_jni_ids(probe);
1622   }
1623   return probe;
1624 }
1625 
1626 
1627 /* jni_id_for for jfieldIds only */
1628 JNIid* InstanceKlass::jni_id_for(int offset) {
1629   JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset);
1630   if (probe == NULL) {
1631     probe = jni_id_for_impl(this, offset);
1632   }
1633   return probe;
1634 }
1635 
1636 u2 InstanceKlass::enclosing_method_data(int offset) const {
1637   const Array<jushort>* const inner_class_list = inner_classes();
1638   if (inner_class_list == NULL) {
1639     return 0;
1640   }
1641   const int length = inner_class_list->length();
1642   if (length % inner_class_next_offset == 0) {
1643     return 0;
1644   }
1645   const int index = length - enclosing_method_attribute_size;
1646   assert(offset < enclosing_method_attribute_size, "invalid offset");
1647   return inner_class_list->at(index + offset);
1648 }
1649 
1650 void InstanceKlass::set_enclosing_method_indices(u2 class_index,
1651                                                  u2 method_index) {
1652   Array<jushort>* inner_class_list = inner_classes();
1653   assert (inner_class_list != NULL, "_inner_classes list is not set up");
1654   int length = inner_class_list->length();
1655   if (length % inner_class_next_offset == enclosing_method_attribute_size) {
1656     int index = length - enclosing_method_attribute_size;
1657     inner_class_list->at_put(
1658       index + enclosing_method_class_index_offset, class_index);
1659     inner_class_list->at_put(
1660       index + enclosing_method_method_index_offset, method_index);
1661   }
1662 }
1663 
1664 // Lookup or create a jmethodID.
1665 // This code is called by the VMThread and JavaThreads so the
1666 // locking has to be done very carefully to avoid deadlocks
1667 // and/or other cache consistency problems.
1668 //
1669 jmethodID InstanceKlass::get_jmethod_id(instanceKlassHandle ik_h, const methodHandle& method_h) {
1670   size_t idnum = (size_t)method_h->method_idnum();
1671   jmethodID* jmeths = ik_h->methods_jmethod_ids_acquire();
1672   size_t length = 0;
1673   jmethodID id = NULL;
1674 
1675   // We use a double-check locking idiom here because this cache is
1676   // performance sensitive. In the normal system, this cache only
1677   // transitions from NULL to non-NULL which is safe because we use
1678   // release_set_methods_jmethod_ids() to advertise the new cache.
1679   // A partially constructed cache should never be seen by a racing
1680   // thread. We also use release_store_ptr() to save a new jmethodID
1681   // in the cache so a partially constructed jmethodID should never be
1682   // seen either. Cache reads of existing jmethodIDs proceed without a
1683   // lock, but cache writes of a new jmethodID requires uniqueness and
1684   // creation of the cache itself requires no leaks so a lock is
1685   // generally acquired in those two cases.
1686   //
1687   // If the RedefineClasses() API has been used, then this cache can
1688   // grow and we'll have transitions from non-NULL to bigger non-NULL.
1689   // Cache creation requires no leaks and we require safety between all
1690   // cache accesses and freeing of the old cache so a lock is generally
1691   // acquired when the RedefineClasses() API has been used.
1692 
1693   if (jmeths != NULL) {
1694     // the cache already exists
1695     if (!ik_h->idnum_can_increment()) {
1696       // the cache can't grow so we can just get the current values
1697       get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1698     } else {
1699       // cache can grow so we have to be more careful
1700       if (Threads::number_of_threads() == 0 ||
1701           SafepointSynchronize::is_at_safepoint()) {
1702         // we're single threaded or at a safepoint - no locking needed
1703         get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1704       } else {
1705         MutexLocker ml(JmethodIdCreation_lock);
1706         get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1707       }
1708     }
1709   }
1710   // implied else:
1711   // we need to allocate a cache so default length and id values are good
1712 
1713   if (jmeths == NULL ||   // no cache yet
1714       length <= idnum ||  // cache is too short
1715       id == NULL) {       // cache doesn't contain entry
1716 
1717     // This function can be called by the VMThread so we have to do all
1718     // things that might block on a safepoint before grabbing the lock.
1719     // Otherwise, we can deadlock with the VMThread or have a cache
1720     // consistency issue. These vars keep track of what we might have
1721     // to free after the lock is dropped.
1722     jmethodID  to_dealloc_id     = NULL;
1723     jmethodID* to_dealloc_jmeths = NULL;
1724 
1725     // may not allocate new_jmeths or use it if we allocate it
1726     jmethodID* new_jmeths = NULL;
1727     if (length <= idnum) {
1728       // allocate a new cache that might be used
1729       size_t size = MAX2(idnum+1, (size_t)ik_h->idnum_allocated_count());
1730       new_jmeths = NEW_C_HEAP_ARRAY(jmethodID, size+1, mtClass);
1731       memset(new_jmeths, 0, (size+1)*sizeof(jmethodID));
1732       // cache size is stored in element[0], other elements offset by one
1733       new_jmeths[0] = (jmethodID)size;
1734     }
1735 
1736     // allocate a new jmethodID that might be used
1737     jmethodID new_id = NULL;
1738     if (method_h->is_old() && !method_h->is_obsolete()) {
1739       // The method passed in is old (but not obsolete), we need to use the current version
1740       Method* current_method = ik_h->method_with_idnum((int)idnum);
1741       assert(current_method != NULL, "old and but not obsolete, so should exist");
1742       new_id = Method::make_jmethod_id(ik_h->class_loader_data(), current_method);
1743     } else {
1744       // It is the current version of the method or an obsolete method,
1745       // use the version passed in
1746       new_id = Method::make_jmethod_id(ik_h->class_loader_data(), method_h());
1747     }
1748 
1749     if (Threads::number_of_threads() == 0 ||
1750         SafepointSynchronize::is_at_safepoint()) {
1751       // we're single threaded or at a safepoint - no locking needed
1752       id = get_jmethod_id_fetch_or_update(ik_h, idnum, new_id, new_jmeths,
1753                                           &to_dealloc_id, &to_dealloc_jmeths);
1754     } else {
1755       MutexLocker ml(JmethodIdCreation_lock);
1756       id = get_jmethod_id_fetch_or_update(ik_h, idnum, new_id, new_jmeths,
1757                                           &to_dealloc_id, &to_dealloc_jmeths);
1758     }
1759 
1760     // The lock has been dropped so we can free resources.
1761     // Free up either the old cache or the new cache if we allocated one.
1762     if (to_dealloc_jmeths != NULL) {
1763       FreeHeap(to_dealloc_jmeths);
1764     }
1765     // free up the new ID since it wasn't needed
1766     if (to_dealloc_id != NULL) {
1767       Method::destroy_jmethod_id(ik_h->class_loader_data(), to_dealloc_id);
1768     }
1769   }
1770   return id;
1771 }
1772 
1773 // Figure out how many jmethodIDs haven't been allocated, and make
1774 // sure space for them is pre-allocated.  This makes getting all
1775 // method ids much, much faster with classes with more than 8
1776 // methods, and has a *substantial* effect on performance with jvmti
1777 // code that loads all jmethodIDs for all classes.
1778 void InstanceKlass::ensure_space_for_methodids(int start_offset) {
1779   int new_jmeths = 0;
1780   int length = methods()->length();
1781   for (int index = start_offset; index < length; index++) {
1782     Method* m = methods()->at(index);
1783     jmethodID id = m->find_jmethod_id_or_null();
1784     if (id == NULL) {
1785       new_jmeths++;
1786     }
1787   }
1788   if (new_jmeths != 0) {
1789     Method::ensure_jmethod_ids(class_loader_data(), new_jmeths);
1790   }
1791 }
1792 
1793 // Common code to fetch the jmethodID from the cache or update the
1794 // cache with the new jmethodID. This function should never do anything
1795 // that causes the caller to go to a safepoint or we can deadlock with
1796 // the VMThread or have cache consistency issues.
1797 //
1798 jmethodID InstanceKlass::get_jmethod_id_fetch_or_update(
1799             instanceKlassHandle ik_h, size_t idnum, jmethodID new_id,
1800             jmethodID* new_jmeths, jmethodID* to_dealloc_id_p,
1801             jmethodID** to_dealloc_jmeths_p) {
1802   assert(new_id != NULL, "sanity check");
1803   assert(to_dealloc_id_p != NULL, "sanity check");
1804   assert(to_dealloc_jmeths_p != NULL, "sanity check");
1805   assert(Threads::number_of_threads() == 0 ||
1806          SafepointSynchronize::is_at_safepoint() ||
1807          JmethodIdCreation_lock->owned_by_self(), "sanity check");
1808 
1809   // reacquire the cache - we are locked, single threaded or at a safepoint
1810   jmethodID* jmeths = ik_h->methods_jmethod_ids_acquire();
1811   jmethodID  id     = NULL;
1812   size_t     length = 0;
1813 
1814   if (jmeths == NULL ||                         // no cache yet
1815       (length = (size_t)jmeths[0]) <= idnum) {  // cache is too short
1816     if (jmeths != NULL) {
1817       // copy any existing entries from the old cache
1818       for (size_t index = 0; index < length; index++) {
1819         new_jmeths[index+1] = jmeths[index+1];
1820       }
1821       *to_dealloc_jmeths_p = jmeths;  // save old cache for later delete
1822     }
1823     ik_h->release_set_methods_jmethod_ids(jmeths = new_jmeths);
1824   } else {
1825     // fetch jmethodID (if any) from the existing cache
1826     id = jmeths[idnum+1];
1827     *to_dealloc_jmeths_p = new_jmeths;  // save new cache for later delete
1828   }
1829   if (id == NULL) {
1830     // No matching jmethodID in the existing cache or we have a new
1831     // cache or we just grew the cache. This cache write is done here
1832     // by the first thread to win the foot race because a jmethodID
1833     // needs to be unique once it is generally available.
1834     id = new_id;
1835 
1836     // The jmethodID cache can be read while unlocked so we have to
1837     // make sure the new jmethodID is complete before installing it
1838     // in the cache.
1839     OrderAccess::release_store_ptr(&jmeths[idnum+1], id);
1840   } else {
1841     *to_dealloc_id_p = new_id; // save new id for later delete
1842   }
1843   return id;
1844 }
1845 
1846 
1847 // Common code to get the jmethodID cache length and the jmethodID
1848 // value at index idnum if there is one.
1849 //
1850 void InstanceKlass::get_jmethod_id_length_value(jmethodID* cache,
1851        size_t idnum, size_t *length_p, jmethodID* id_p) {
1852   assert(cache != NULL, "sanity check");
1853   assert(length_p != NULL, "sanity check");
1854   assert(id_p != NULL, "sanity check");
1855 
1856   // cache size is stored in element[0], other elements offset by one
1857   *length_p = (size_t)cache[0];
1858   if (*length_p <= idnum) {  // cache is too short
1859     *id_p = NULL;
1860   } else {
1861     *id_p = cache[idnum+1];  // fetch jmethodID (if any)
1862   }
1863 }
1864 
1865 
1866 // Lookup a jmethodID, NULL if not found.  Do no blocking, no allocations, no handles
1867 jmethodID InstanceKlass::jmethod_id_or_null(Method* method) {
1868   size_t idnum = (size_t)method->method_idnum();
1869   jmethodID* jmeths = methods_jmethod_ids_acquire();
1870   size_t length;                                // length assigned as debugging crumb
1871   jmethodID id = NULL;
1872   if (jmeths != NULL &&                         // If there is a cache
1873       (length = (size_t)jmeths[0]) > idnum) {   // and if it is long enough,
1874     id = jmeths[idnum+1];                       // Look up the id (may be NULL)
1875   }
1876   return id;
1877 }
1878 
1879 inline DependencyContext InstanceKlass::dependencies() {
1880   DependencyContext dep_context(&_dep_context);
1881   return dep_context;
1882 }
1883 
1884 int InstanceKlass::mark_dependent_nmethods(DepChange& changes) {
1885   return dependencies().mark_dependent_nmethods(changes);
1886 }
1887 
1888 void InstanceKlass::add_dependent_nmethod(nmethod* nm) {
1889   dependencies().add_dependent_nmethod(nm);
1890 }
1891 
1892 void InstanceKlass::remove_dependent_nmethod(nmethod* nm, bool delete_immediately) {
1893   dependencies().remove_dependent_nmethod(nm, delete_immediately);
1894 }
1895 
1896 #ifndef PRODUCT
1897 void InstanceKlass::print_dependent_nmethods(bool verbose) {
1898   dependencies().print_dependent_nmethods(verbose);
1899 }
1900 
1901 bool InstanceKlass::is_dependent_nmethod(nmethod* nm) {
1902   return dependencies().is_dependent_nmethod(nm);
1903 }
1904 #endif //PRODUCT
1905 
1906 void InstanceKlass::clean_weak_instanceklass_links(BoolObjectClosure* is_alive) {
1907   clean_implementors_list(is_alive);
1908   clean_method_data(is_alive);
1909 
1910   // Since GC iterates InstanceKlasses sequentially, it is safe to remove stale entries here.
1911   DependencyContext dep_context(&_dep_context);
1912   dep_context.expunge_stale_entries();
1913 }
1914 
1915 void InstanceKlass::clean_implementors_list(BoolObjectClosure* is_alive) {
1916   assert(class_loader_data()->is_alive(is_alive), "this klass should be live");
1917   if (is_interface()) {
1918     if (ClassUnloading) {
1919       Klass* impl = implementor();
1920       if (impl != NULL) {
1921         if (!impl->is_loader_alive(is_alive)) {
1922           // remove this guy
1923           Klass** klass = adr_implementor();
1924           assert(klass != NULL, "null klass");
1925           if (klass != NULL) {
1926             *klass = NULL;
1927           }
1928         }
1929       }
1930     }
1931   }
1932 }
1933 
1934 void InstanceKlass::clean_method_data(BoolObjectClosure* is_alive) {
1935   for (int m = 0; m < methods()->length(); m++) {
1936     MethodData* mdo = methods()->at(m)->method_data();
1937     if (mdo != NULL) {
1938       mdo->clean_method_data(is_alive);
1939     }
1940   }
1941 }
1942 
1943 
1944 static void remove_unshareable_in_class(Klass* k) {
1945   // remove klass's unshareable info
1946   k->remove_unshareable_info();
1947 }
1948 
1949 void InstanceKlass::remove_unshareable_info() {
1950   Klass::remove_unshareable_info();
1951   // Unlink the class
1952   if (is_linked()) {
1953     unlink_class();
1954   }
1955   init_implementor();
1956 
1957   constants()->remove_unshareable_info();
1958 
1959   assert(_dep_context == DependencyContext::EMPTY, "dependency context is not shareable");
1960 
1961   for (int i = 0; i < methods()->length(); i++) {
1962     Method* m = methods()->at(i);
1963     m->remove_unshareable_info();
1964   }
1965 
1966   // do array classes also.
1967   array_klasses_do(remove_unshareable_in_class);
1968 }
1969 
1970 static void restore_unshareable_in_class(Klass* k, TRAPS) {
1971   // Array classes have null protection domain.
1972   // --> see ArrayKlass::complete_create_array_klass()
1973   k->restore_unshareable_info(ClassLoaderData::the_null_class_loader_data(), Handle(), CHECK);
1974 }
1975 
1976 void InstanceKlass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain, TRAPS) {
1977   Klass::restore_unshareable_info(loader_data, protection_domain, CHECK);
1978   instanceKlassHandle ik(THREAD, this);
1979 
1980   Array<Method*>* methods = ik->methods();
1981   int num_methods = methods->length();
1982   for (int index2 = 0; index2 < num_methods; ++index2) {
1983     methodHandle m(THREAD, methods->at(index2));
1984     m->restore_unshareable_info(CHECK);
1985   }
1986   if (JvmtiExport::has_redefined_a_class()) {
1987     // Reinitialize vtable because RedefineClasses may have changed some
1988     // entries in this vtable for super classes so the CDS vtable might
1989     // point to old or obsolete entries.  RedefineClasses doesn't fix up
1990     // vtables in the shared system dictionary, only the main one.
1991     // It also redefines the itable too so fix that too.
1992     ResourceMark rm(THREAD);
1993     ik->vtable()->initialize_vtable(false, CHECK);
1994     ik->itable()->initialize_itable(false, CHECK);
1995   }
1996 
1997   // restore constant pool resolved references
1998   ik->constants()->restore_unshareable_info(CHECK);
1999 
2000   ik->array_klasses_do(restore_unshareable_in_class, CHECK);
2001 }
2002 
2003 // returns true IFF is_in_error_state() has been changed as a result of this call.
2004 bool InstanceKlass::check_sharing_error_state() {
2005   assert(DumpSharedSpaces, "should only be called during dumping");
2006   bool old_state = is_in_error_state();
2007 
2008   if (!is_in_error_state()) {
2009     bool bad = false;
2010     for (InstanceKlass* sup = java_super(); sup; sup = sup->java_super()) {
2011       if (sup->is_in_error_state()) {
2012         bad = true;
2013         break;
2014       }
2015     }
2016     if (!bad) {
2017       Array<Klass*>* interfaces = transitive_interfaces();
2018       for (int i = 0; i < interfaces->length(); i++) {
2019         Klass* iface = interfaces->at(i);
2020         if (InstanceKlass::cast(iface)->is_in_error_state()) {
2021           bad = true;
2022           break;
2023         }
2024       }
2025     }
2026 
2027     if (bad) {
2028       set_in_error_state();
2029     }
2030   }
2031 
2032   return (old_state != is_in_error_state());
2033 }
2034 
2035 static void clear_all_breakpoints(Method* m) {
2036   m->clear_all_breakpoints();
2037 }
2038 
2039 
2040 void InstanceKlass::notify_unload_class(InstanceKlass* ik) {
2041   // notify the debugger
2042   if (JvmtiExport::should_post_class_unload()) {
2043     JvmtiExport::post_class_unload(ik);
2044   }
2045 
2046   // notify ClassLoadingService of class unload
2047   ClassLoadingService::notify_class_unloaded(ik);
2048 }
2049 
2050 void InstanceKlass::release_C_heap_structures(InstanceKlass* ik) {
2051   // Clean up C heap
2052   ik->release_C_heap_structures();
2053   ik->constants()->release_C_heap_structures();
2054 }
2055 
2056 void InstanceKlass::release_C_heap_structures() {
2057 
2058   // Can't release the constant pool here because the constant pool can be
2059   // deallocated separately from the InstanceKlass for default methods and
2060   // redefine classes.
2061 
2062   // Deallocate oop map cache
2063   if (_oop_map_cache != NULL) {
2064     delete _oop_map_cache;
2065     _oop_map_cache = NULL;
2066   }
2067 
2068   // Deallocate JNI identifiers for jfieldIDs
2069   JNIid::deallocate(jni_ids());
2070   set_jni_ids(NULL);
2071 
2072   jmethodID* jmeths = methods_jmethod_ids_acquire();
2073   if (jmeths != (jmethodID*)NULL) {
2074     release_set_methods_jmethod_ids(NULL);
2075     FreeHeap(jmeths);
2076   }
2077 
2078   // Deallocate MemberNameTable
2079   {
2080     Mutex* lock_or_null = SafepointSynchronize::is_at_safepoint() ? NULL : MemberNameTable_lock;
2081     MutexLockerEx ml(lock_or_null, Mutex::_no_safepoint_check_flag);
2082     MemberNameTable* mnt = member_names();
2083     if (mnt != NULL) {
2084       delete mnt;
2085       set_member_names(NULL);
2086     }
2087   }
2088 
2089   // Release dependencies.
2090   // It is desirable to use DC::remove_all_dependents() here, but, unfortunately,
2091   // it is not safe (see JDK-8143408). The problem is that the klass dependency
2092   // context can contain live dependencies, since there's a race between nmethod &
2093   // klass unloading. If the klass is dead when nmethod unloading happens, relevant
2094   // dependencies aren't removed from the context associated with the class (see
2095   // nmethod::flush_dependencies). It ends up during klass unloading as seemingly
2096   // live dependencies pointing to unloaded nmethods and causes a crash in
2097   // DC::remove_all_dependents() when it touches unloaded nmethod.
2098   dependencies().wipe();
2099 
2100   // Deallocate breakpoint records
2101   if (breakpoints() != 0x0) {
2102     methods_do(clear_all_breakpoints);
2103     assert(breakpoints() == 0x0, "should have cleared breakpoints");
2104   }
2105 
2106   // deallocate the cached class file
2107   if (_cached_class_file != NULL) {
2108     os::free(_cached_class_file);
2109     _cached_class_file = NULL;
2110   }
2111 
2112   // Decrement symbol reference counts associated with the unloaded class.
2113   if (_name != NULL) _name->decrement_refcount();
2114   // unreference array name derived from this class name (arrays of an unloaded
2115   // class can't be referenced anymore).
2116   if (_array_name != NULL)  _array_name->decrement_refcount();
2117   if (_source_debug_extension != NULL) FREE_C_HEAP_ARRAY(char, _source_debug_extension);
2118 
2119   assert(_total_instanceKlass_count >= 1, "Sanity check");
2120   Atomic::dec(&_total_instanceKlass_count);
2121 }
2122 
2123 void InstanceKlass::set_source_debug_extension(const char* array, int length) {
2124   if (array == NULL) {
2125     _source_debug_extension = NULL;
2126   } else {
2127     // Adding one to the attribute length in order to store a null terminator
2128     // character could cause an overflow because the attribute length is
2129     // already coded with an u4 in the classfile, but in practice, it's
2130     // unlikely to happen.
2131     assert((length+1) > length, "Overflow checking");
2132     char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass);
2133     for (int i = 0; i < length; i++) {
2134       sde[i] = array[i];
2135     }
2136     sde[length] = '\0';
2137     _source_debug_extension = sde;
2138   }
2139 }
2140 
2141 address InstanceKlass::static_field_addr(int offset) {
2142   return (address)(offset + InstanceMirrorKlass::offset_of_static_fields() + cast_from_oop<intptr_t>(java_mirror()));
2143 }
2144 
2145 
2146 const char* InstanceKlass::signature_name() const {
2147   int hash_len = 0;
2148   char hash_buf[40];
2149 
2150   // If this is an anonymous class, append a hash to make the name unique
2151   if (is_anonymous()) {
2152     intptr_t hash = (java_mirror() != NULL) ? java_mirror()->identity_hash() : 0;
2153     jio_snprintf(hash_buf, sizeof(hash_buf), "/" UINTX_FORMAT, (uintx)hash);
2154     hash_len = (int)strlen(hash_buf);
2155   }
2156 
2157   // Get the internal name as a c string
2158   const char* src = (const char*) (name()->as_C_string());
2159   const int src_length = (int)strlen(src);
2160 
2161   char* dest = NEW_RESOURCE_ARRAY(char, src_length + hash_len + 3);
2162 
2163   // Add L as type indicator
2164   int dest_index = 0;
2165   dest[dest_index++] = 'L';
2166 
2167   // Add the actual class name
2168   for (int src_index = 0; src_index < src_length; ) {
2169     dest[dest_index++] = src[src_index++];
2170   }
2171 
2172   // If we have a hash, append it
2173   for (int hash_index = 0; hash_index < hash_len; ) {
2174     dest[dest_index++] = hash_buf[hash_index++];
2175   }
2176 
2177   // Add the semicolon and the NULL
2178   dest[dest_index++] = ';';
2179   dest[dest_index] = '\0';
2180   return dest;
2181 }
2182 
2183 // different verisons of is_same_class_package
2184 bool InstanceKlass::is_same_class_package(const Klass* class2) const {
2185   const Klass* const class1 = (const Klass* const)this;
2186   oop classloader1 = InstanceKlass::cast(class1)->class_loader();
2187   const Symbol* const classname1 = class1->name();
2188 
2189   if (class2->is_objArray_klass()) {
2190     class2 = ObjArrayKlass::cast(class2)->bottom_klass();
2191   }
2192   oop classloader2;
2193   if (class2->is_instance_klass()) {
2194     classloader2 = InstanceKlass::cast(class2)->class_loader();
2195   } else {
2196     assert(class2->is_typeArray_klass(), "should be type array");
2197     classloader2 = NULL;
2198   }
2199   const Symbol* classname2 = class2->name();
2200 
2201   return InstanceKlass::is_same_class_package(classloader1, classname1,
2202                                               classloader2, classname2);
2203 }
2204 
2205 bool InstanceKlass::is_same_class_package(oop other_class_loader,
2206                                           const Symbol* other_class_name) const {
2207   oop this_class_loader = class_loader();
2208   const Symbol* const this_class_name = name();
2209 
2210   return InstanceKlass::is_same_class_package(this_class_loader,
2211                                              this_class_name,
2212                                              other_class_loader,
2213                                              other_class_name);
2214 }
2215 
2216 // return true if two classes are in the same package, classloader
2217 // and classname information is enough to determine a class's package
2218 bool InstanceKlass::is_same_class_package(oop class_loader1, const Symbol* class_name1,
2219                                           oop class_loader2, const Symbol* class_name2) {
2220   if (class_loader1 != class_loader2) {
2221     return false;
2222   } else if (class_name1 == class_name2) {
2223     return true;                // skip painful bytewise comparison
2224   } else {
2225     ResourceMark rm;
2226 
2227     // The Symbol*'s are in UTF8 encoding. Since we only need to check explicitly
2228     // for ASCII characters ('/', 'L', '['), we can keep them in UTF8 encoding.
2229     // Otherwise, we just compare jbyte values between the strings.
2230     const jbyte *name1 = class_name1->base();
2231     const jbyte *name2 = class_name2->base();
2232 
2233     const jbyte *last_slash1 = UTF8::strrchr(name1, class_name1->utf8_length(), '/');
2234     const jbyte *last_slash2 = UTF8::strrchr(name2, class_name2->utf8_length(), '/');
2235 
2236     if ((last_slash1 == NULL) || (last_slash2 == NULL)) {
2237       // One of the two doesn't have a package.  Only return true
2238       // if the other one also doesn't have a package.
2239       return last_slash1 == last_slash2;
2240     } else {
2241       // Skip over '['s
2242       if (*name1 == '[') {
2243         do {
2244           name1++;
2245         } while (*name1 == '[');
2246         if (*name1 != 'L') {
2247           // Something is terribly wrong.  Shouldn't be here.
2248           return false;
2249         }
2250       }
2251       if (*name2 == '[') {
2252         do {
2253           name2++;
2254         } while (*name2 == '[');
2255         if (*name2 != 'L') {
2256           // Something is terribly wrong.  Shouldn't be here.
2257           return false;
2258         }
2259       }
2260 
2261       // Check that package part is identical
2262       int length1 = last_slash1 - name1;
2263       int length2 = last_slash2 - name2;
2264 
2265       return UTF8::equal(name1, length1, name2, length2);
2266     }
2267   }
2268 }
2269 
2270 // Returns true iff super_method can be overridden by a method in targetclassname
2271 // See JSL 3rd edition 8.4.6.1
2272 // Assumes name-signature match
2273 // "this" is InstanceKlass of super_method which must exist
2274 // note that the InstanceKlass of the method in the targetclassname has not always been created yet
2275 bool InstanceKlass::is_override(const methodHandle& super_method, Handle targetclassloader, Symbol* targetclassname, TRAPS) {
2276    // Private methods can not be overridden
2277    if (super_method->is_private()) {
2278      return false;
2279    }
2280    // If super method is accessible, then override
2281    if ((super_method->is_protected()) ||
2282        (super_method->is_public())) {
2283      return true;
2284    }
2285    // Package-private methods are not inherited outside of package
2286    assert(super_method->is_package_private(), "must be package private");
2287    return(is_same_class_package(targetclassloader(), targetclassname));
2288 }
2289 
2290 /* defined for now in jvm.cpp, for historical reasons *--
2291 Klass* InstanceKlass::compute_enclosing_class_impl(instanceKlassHandle self,
2292                                                      Symbol*& simple_name_result, TRAPS) {
2293   ...
2294 }
2295 */
2296 
2297 // tell if two classes have the same enclosing class (at package level)
2298 bool InstanceKlass::is_same_package_member_impl(const InstanceKlass* class1,
2299                                                 const Klass* class2,
2300                                                 TRAPS) {
2301   if (class2 == class1) return true;
2302   if (!class2->is_instance_klass())  return false;
2303 
2304   // must be in same package before we try anything else
2305   if (!class1->is_same_class_package(class2->class_loader(), class2->name()))
2306     return false;
2307 
2308   // As long as there is an outer1.getEnclosingClass,
2309   // shift the search outward.
2310   const InstanceKlass* outer1 = class1;
2311   for (;;) {
2312     // As we walk along, look for equalities between outer1 and class2.
2313     // Eventually, the walks will terminate as outer1 stops
2314     // at the top-level class around the original class.
2315     bool ignore_inner_is_member;
2316     const Klass* next = outer1->compute_enclosing_class(&ignore_inner_is_member,
2317                                                   CHECK_false);
2318     if (next == NULL)  break;
2319     if (next == class2)  return true;
2320     outer1 = InstanceKlass::cast(next);
2321   }
2322 
2323   // Now do the same for class2.
2324   const InstanceKlass* outer2 = InstanceKlass::cast(class2);
2325   for (;;) {
2326     bool ignore_inner_is_member;
2327     Klass* next = outer2->compute_enclosing_class(&ignore_inner_is_member,
2328                                                     CHECK_false);
2329     if (next == NULL)  break;
2330     // Might as well check the new outer against all available values.
2331     if (next == class1)  return true;
2332     if (next == outer1)  return true;
2333     outer2 = InstanceKlass::cast(next);
2334   }
2335 
2336   // If by this point we have not found an equality between the
2337   // two classes, we know they are in separate package members.
2338   return false;
2339 }
2340 
2341 bool InstanceKlass::find_inner_classes_attr(instanceKlassHandle k, int* ooff, int* noff, TRAPS) {
2342   constantPoolHandle i_cp(THREAD, k->constants());
2343   for (InnerClassesIterator iter(k); !iter.done(); iter.next()) {
2344     int ioff = iter.inner_class_info_index();
2345     if (ioff != 0) {
2346       // Check to see if the name matches the class we're looking for
2347       // before attempting to find the class.
2348       if (i_cp->klass_name_at_matches(k, ioff)) {
2349         Klass* inner_klass = i_cp->klass_at(ioff, CHECK_false);
2350         if (k() == inner_klass) {
2351           *ooff = iter.outer_class_info_index();
2352           *noff = iter.inner_name_index();
2353           return true;
2354         }
2355       }
2356     }
2357   }
2358   return false;
2359 }
2360 
2361 InstanceKlass* InstanceKlass::compute_enclosing_class_impl(const InstanceKlass* k,
2362                                                            bool* inner_is_member,
2363                                                            TRAPS) {
2364   InstanceKlass* outer_klass = NULL;
2365   *inner_is_member = false;
2366   int ooff = 0, noff = 0;
2367   if (find_inner_classes_attr(k, &ooff, &noff, THREAD)) {
2368     constantPoolHandle i_cp(THREAD, k->constants());
2369     if (ooff != 0) {
2370       Klass* ok = i_cp->klass_at(ooff, CHECK_NULL);
2371       outer_klass = InstanceKlass::cast(ok);
2372       *inner_is_member = true;
2373     }
2374     if (NULL == outer_klass) {
2375       // It may be anonymous; try for that.
2376       int encl_method_class_idx = k->enclosing_method_class_index();
2377       if (encl_method_class_idx != 0) {
2378         Klass* ok = i_cp->klass_at(encl_method_class_idx, CHECK_NULL);
2379         outer_klass = InstanceKlass::cast(ok);
2380         *inner_is_member = false;
2381       }
2382     }
2383   }
2384 
2385   // If no inner class attribute found for this class.
2386   if (NULL == outer_klass) return NULL;
2387 
2388   // Throws an exception if outer klass has not declared k as an inner klass
2389   // We need evidence that each klass knows about the other, or else
2390   // the system could allow a spoof of an inner class to gain access rights.
2391   Reflection::check_for_inner_class(outer_klass, k, *inner_is_member, CHECK_NULL);
2392   return outer_klass;
2393 }
2394 
2395 jint InstanceKlass::compute_modifier_flags(TRAPS) const {
2396   jint access = access_flags().as_int();
2397 
2398   // But check if it happens to be member class.
2399   instanceKlassHandle ik(THREAD, this);
2400   InnerClassesIterator iter(ik);
2401   for (; !iter.done(); iter.next()) {
2402     int ioff = iter.inner_class_info_index();
2403     // Inner class attribute can be zero, skip it.
2404     // Strange but true:  JVM spec. allows null inner class refs.
2405     if (ioff == 0) continue;
2406 
2407     // only look at classes that are already loaded
2408     // since we are looking for the flags for our self.
2409     Symbol* inner_name = ik->constants()->klass_name_at(ioff);
2410     if ((ik->name() == inner_name)) {
2411       // This is really a member class.
2412       access = iter.inner_access_flags();
2413       break;
2414     }
2415   }
2416   // Remember to strip ACC_SUPER bit
2417   return (access & (~JVM_ACC_SUPER)) & JVM_ACC_WRITTEN_FLAGS;
2418 }
2419 
2420 jint InstanceKlass::jvmti_class_status() const {
2421   jint result = 0;
2422 
2423   if (is_linked()) {
2424     result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED;
2425   }
2426 
2427   if (is_initialized()) {
2428     assert(is_linked(), "Class status is not consistent");
2429     result |= JVMTI_CLASS_STATUS_INITIALIZED;
2430   }
2431   if (is_in_error_state()) {
2432     result |= JVMTI_CLASS_STATUS_ERROR;
2433   }
2434   return result;
2435 }
2436 
2437 Method* InstanceKlass::method_at_itable(Klass* holder, int index, TRAPS) {
2438   itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2439   int method_table_offset_in_words = ioe->offset()/wordSize;
2440   int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words())
2441                        / itableOffsetEntry::size();
2442 
2443   for (int cnt = 0 ; ; cnt ++, ioe ++) {
2444     // If the interface isn't implemented by the receiver class,
2445     // the VM should throw IncompatibleClassChangeError.
2446     if (cnt >= nof_interfaces) {
2447       THROW_NULL(vmSymbols::java_lang_IncompatibleClassChangeError());
2448     }
2449 
2450     Klass* ik = ioe->interface_klass();
2451     if (ik == holder) break;
2452   }
2453 
2454   itableMethodEntry* ime = ioe->first_method_entry(this);
2455   Method* m = ime[index].method();
2456   if (m == NULL) {
2457     THROW_NULL(vmSymbols::java_lang_AbstractMethodError());
2458   }
2459   return m;
2460 }
2461 
2462 
2463 #if INCLUDE_JVMTI
2464 // update default_methods for redefineclasses for methods that are
2465 // not yet in the vtable due to concurrent subclass define and superinterface
2466 // redefinition
2467 // Note: those in the vtable, should have been updated via adjust_method_entries
2468 void InstanceKlass::adjust_default_methods(InstanceKlass* holder, bool* trace_name_printed) {
2469   // search the default_methods for uses of either obsolete or EMCP methods
2470   if (default_methods() != NULL) {
2471     for (int index = 0; index < default_methods()->length(); index ++) {
2472       Method* old_method = default_methods()->at(index);
2473       if (old_method == NULL || old_method->method_holder() != holder || !old_method->is_old()) {
2474         continue; // skip uninteresting entries
2475       }
2476       assert(!old_method->is_deleted(), "default methods may not be deleted");
2477 
2478       Method* new_method = holder->method_with_idnum(old_method->orig_method_idnum());
2479 
2480       assert(new_method != NULL, "method_with_idnum() should not be NULL");
2481       assert(old_method != new_method, "sanity check");
2482 
2483       default_methods()->at_put(index, new_method);
2484       if (RC_TRACE_IN_RANGE(0x00100000, 0x00400000)) {
2485         if (!(*trace_name_printed)) {
2486           // RC_TRACE_MESG macro has an embedded ResourceMark
2487           RC_TRACE_MESG(("adjust: klassname=%s default methods from name=%s",
2488                          external_name(),
2489                          old_method->method_holder()->external_name()));
2490           *trace_name_printed = true;
2491         }
2492         RC_TRACE(0x00100000, ("default method update: %s(%s) ",
2493                               new_method->name()->as_C_string(),
2494                               new_method->signature()->as_C_string()));
2495       }
2496     }
2497   }
2498 }
2499 #endif // INCLUDE_JVMTI
2500 
2501 // On-stack replacement stuff
2502 void InstanceKlass::add_osr_nmethod(nmethod* n) {
2503   // only one compilation can be active
2504   {
2505     // This is a short non-blocking critical region, so the no safepoint check is ok.
2506     MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2507     assert(n->is_osr_method(), "wrong kind of nmethod");
2508     n->set_osr_link(osr_nmethods_head());
2509     set_osr_nmethods_head(n);
2510     // Raise the highest osr level if necessary
2511     if (TieredCompilation) {
2512       Method* m = n->method();
2513       m->set_highest_osr_comp_level(MAX2(m->highest_osr_comp_level(), n->comp_level()));
2514     }
2515   }
2516 
2517   // Get rid of the osr methods for the same bci that have lower levels.
2518   if (TieredCompilation) {
2519     for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) {
2520       nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true);
2521       if (inv != NULL && inv->is_in_use()) {
2522         inv->make_not_entrant();
2523       }
2524     }
2525   }
2526 }
2527 
2528 
2529 void InstanceKlass::remove_osr_nmethod(nmethod* n) {
2530   // This is a short non-blocking critical region, so the no safepoint check is ok.
2531   MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2532   assert(n->is_osr_method(), "wrong kind of nmethod");
2533   nmethod* last = NULL;
2534   nmethod* cur  = osr_nmethods_head();
2535   int max_level = CompLevel_none;  // Find the max comp level excluding n
2536   Method* m = n->method();
2537   // Search for match
2538   while(cur != NULL && cur != n) {
2539     if (TieredCompilation && m == cur->method()) {
2540       // Find max level before n
2541       max_level = MAX2(max_level, cur->comp_level());
2542     }
2543     last = cur;
2544     cur = cur->osr_link();
2545   }
2546   nmethod* next = NULL;
2547   if (cur == n) {
2548     next = cur->osr_link();
2549     if (last == NULL) {
2550       // Remove first element
2551       set_osr_nmethods_head(next);
2552     } else {
2553       last->set_osr_link(next);
2554     }
2555   }
2556   n->set_osr_link(NULL);
2557   if (TieredCompilation) {
2558     cur = next;
2559     while (cur != NULL) {
2560       // Find max level after n
2561       if (m == cur->method()) {
2562         max_level = MAX2(max_level, cur->comp_level());
2563       }
2564       cur = cur->osr_link();
2565     }
2566     m->set_highest_osr_comp_level(max_level);
2567   }
2568 }
2569 
2570 int InstanceKlass::mark_osr_nmethods(const Method* m) {
2571   // This is a short non-blocking critical region, so the no safepoint check is ok.
2572   MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2573   nmethod* osr = osr_nmethods_head();
2574   int found = 0;
2575   while (osr != NULL) {
2576     assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
2577     if (osr->method() == m) {
2578       osr->mark_for_deoptimization();
2579       found++;
2580     }
2581     osr = osr->osr_link();
2582   }
2583   return found;
2584 }
2585 
2586 nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const {
2587   // This is a short non-blocking critical region, so the no safepoint check is ok.
2588   MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2589   nmethod* osr = osr_nmethods_head();
2590   nmethod* best = NULL;
2591   while (osr != NULL) {
2592     assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
2593     // There can be a time when a c1 osr method exists but we are waiting
2594     // for a c2 version. When c2 completes its osr nmethod we will trash
2595     // the c1 version and only be able to find the c2 version. However
2596     // while we overflow in the c1 code at back branches we don't want to
2597     // try and switch to the same code as we are already running
2598 
2599     if (osr->method() == m &&
2600         (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) {
2601       if (match_level) {
2602         if (osr->comp_level() == comp_level) {
2603           // Found a match - return it.
2604           return osr;
2605         }
2606       } else {
2607         if (best == NULL || (osr->comp_level() > best->comp_level())) {
2608           if (osr->comp_level() == CompLevel_highest_tier) {
2609             // Found the best possible - return it.
2610             return osr;
2611           }
2612           best = osr;
2613         }
2614       }
2615     }
2616     osr = osr->osr_link();
2617   }
2618   if (best != NULL && best->comp_level() >= comp_level && match_level == false) {
2619     return best;
2620   }
2621   return NULL;
2622 }
2623 
2624 bool InstanceKlass::add_member_name(Handle mem_name) {
2625   jweak mem_name_wref = JNIHandles::make_weak_global(mem_name);
2626   MutexLocker ml(MemberNameTable_lock);
2627   DEBUG_ONLY(No_Safepoint_Verifier nsv);
2628 
2629   // Check if method has been redefined while taking out MemberNameTable_lock, if so
2630   // return false.  We cannot cache obsolete methods. They will crash when the function
2631   // is called!
2632   Method* method = (Method*)java_lang_invoke_MemberName::vmtarget(mem_name());
2633   if (method->is_obsolete()) {
2634     return false;
2635   } else if (method->is_old()) {
2636     // Replace method with redefined version
2637     java_lang_invoke_MemberName::set_vmtarget(mem_name(), method_with_idnum(method->method_idnum()));
2638   }
2639 
2640   if (_member_names == NULL) {
2641     _member_names = new (ResourceObj::C_HEAP, mtClass) MemberNameTable(idnum_allocated_count());
2642   }
2643   _member_names->add_member_name(mem_name_wref);
2644   return true;
2645 }
2646 
2647 // -----------------------------------------------------------------------------------------------------
2648 // Printing
2649 
2650 #ifndef PRODUCT
2651 
2652 #define BULLET  " - "
2653 
2654 static const char* state_names[] = {
2655   "allocated", "loaded", "linked", "being_initialized", "fully_initialized", "initialization_error"
2656 };
2657 
2658 static void print_vtable(intptr_t* start, int len, outputStream* st) {
2659   for (int i = 0; i < len; i++) {
2660     intptr_t e = start[i];
2661     st->print("%d : " INTPTR_FORMAT, i, e);
2662     if (e != 0 && ((Metadata*)e)->is_metaspace_object()) {
2663       st->print(" ");
2664       ((Metadata*)e)->print_value_on(st);
2665     }
2666     st->cr();
2667   }
2668 }
2669 
2670 void InstanceKlass::print_on(outputStream* st) const {
2671   assert(is_klass(), "must be klass");
2672   Klass::print_on(st);
2673 
2674   st->print(BULLET"instance size:     %d", size_helper());                        st->cr();
2675   st->print(BULLET"klass size:        %d", size());                               st->cr();
2676   st->print(BULLET"access:            "); access_flags().print_on(st);            st->cr();
2677   st->print(BULLET"state:             "); st->print_cr("%s", state_names[_init_state]);
2678   st->print(BULLET"name:              "); name()->print_value_on(st);             st->cr();
2679   st->print(BULLET"super:             "); super()->print_value_on_maybe_null(st); st->cr();
2680   st->print(BULLET"sub:               ");
2681   Klass* sub = subklass();
2682   int n;
2683   for (n = 0; sub != NULL; n++, sub = sub->next_sibling()) {
2684     if (n < MaxSubklassPrintSize) {
2685       sub->print_value_on(st);
2686       st->print("   ");
2687     }
2688   }
2689   if (n >= MaxSubklassPrintSize) st->print("(" INTX_FORMAT " more klasses...)", n - MaxSubklassPrintSize);
2690   st->cr();
2691 
2692   if (is_interface()) {
2693     st->print_cr(BULLET"nof implementors:  %d", nof_implementors());
2694     if (nof_implementors() == 1) {
2695       st->print_cr(BULLET"implementor:    ");
2696       st->print("   ");
2697       implementor()->print_value_on(st);
2698       st->cr();
2699     }
2700   }
2701 
2702   st->print(BULLET"arrays:            "); array_klasses()->print_value_on_maybe_null(st); st->cr();
2703   st->print(BULLET"methods:           "); methods()->print_value_on(st);                  st->cr();
2704   if (Verbose || WizardMode) {
2705     Array<Method*>* method_array = methods();
2706     for (int i = 0; i < method_array->length(); i++) {
2707       st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
2708     }
2709   }
2710   st->print(BULLET"method ordering:   "); method_ordering()->print_value_on(st);      st->cr();
2711   st->print(BULLET"default_methods:   "); default_methods()->print_value_on(st);      st->cr();
2712   if (Verbose && default_methods() != NULL) {
2713     Array<Method*>* method_array = default_methods();
2714     for (int i = 0; i < method_array->length(); i++) {
2715       st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
2716     }
2717   }
2718   if (default_vtable_indices() != NULL) {
2719     st->print(BULLET"default vtable indices:   "); default_vtable_indices()->print_value_on(st);       st->cr();
2720   }
2721   st->print(BULLET"local interfaces:  "); local_interfaces()->print_value_on(st);      st->cr();
2722   st->print(BULLET"trans. interfaces: "); transitive_interfaces()->print_value_on(st); st->cr();
2723   st->print(BULLET"constants:         "); constants()->print_value_on(st);         st->cr();
2724   if (class_loader_data() != NULL) {
2725     st->print(BULLET"class loader data:  ");
2726     class_loader_data()->print_value_on(st);
2727     st->cr();
2728   }
2729   st->print(BULLET"host class:        "); host_klass()->print_value_on_maybe_null(st); st->cr();
2730   if (source_file_name() != NULL) {
2731     st->print(BULLET"source file:       ");
2732     source_file_name()->print_value_on(st);
2733     st->cr();
2734   }
2735   if (source_debug_extension() != NULL) {
2736     st->print(BULLET"source debug extension:       ");
2737     st->print("%s", source_debug_extension());
2738     st->cr();
2739   }
2740   st->print(BULLET"class annotations:       "); class_annotations()->print_value_on(st); st->cr();
2741   st->print(BULLET"class type annotations:  "); class_type_annotations()->print_value_on(st); st->cr();
2742   st->print(BULLET"field annotations:       "); fields_annotations()->print_value_on(st); st->cr();
2743   st->print(BULLET"field type annotations:  "); fields_type_annotations()->print_value_on(st); st->cr();
2744   {
2745     bool have_pv = false;
2746     // previous versions are linked together through the InstanceKlass
2747     for (InstanceKlass* pv_node = _previous_versions;
2748          pv_node != NULL;
2749          pv_node = pv_node->previous_versions()) {
2750       if (!have_pv)
2751         st->print(BULLET"previous version:  ");
2752       have_pv = true;
2753       pv_node->constants()->print_value_on(st);
2754     }
2755     if (have_pv) st->cr();
2756   }
2757 
2758   if (generic_signature() != NULL) {
2759     st->print(BULLET"generic signature: ");
2760     generic_signature()->print_value_on(st);
2761     st->cr();
2762   }
2763   st->print(BULLET"inner classes:     "); inner_classes()->print_value_on(st);     st->cr();
2764   st->print(BULLET"java mirror:       "); java_mirror()->print_value_on(st);       st->cr();
2765   st->print(BULLET"vtable length      %d  (start addr: " INTPTR_FORMAT ")", vtable_length(), p2i(start_of_vtable())); st->cr();
2766   if (vtable_length() > 0 && (Verbose || WizardMode))  print_vtable(start_of_vtable(), vtable_length(), st);
2767   st->print(BULLET"itable length      %d (start addr: " INTPTR_FORMAT ")", itable_length(), p2i(start_of_itable())); st->cr();
2768   if (itable_length() > 0 && (Verbose || WizardMode))  print_vtable(start_of_itable(), itable_length(), st);
2769   st->print_cr(BULLET"---- static fields (%d words):", static_field_size());
2770   FieldPrinter print_static_field(st);
2771   ((InstanceKlass*)this)->do_local_static_fields(&print_static_field);
2772   st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size());
2773   FieldPrinter print_nonstatic_field(st);
2774   InstanceKlass* ik = const_cast<InstanceKlass*>(this);
2775   ik->do_nonstatic_fields(&print_nonstatic_field);
2776 
2777   st->print(BULLET"non-static oop maps: ");
2778   OopMapBlock* map     = start_of_nonstatic_oop_maps();
2779   OopMapBlock* end_map = map + nonstatic_oop_map_count();
2780   while (map < end_map) {
2781     st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1));
2782     map++;
2783   }
2784   st->cr();
2785 }
2786 
2787 #endif //PRODUCT
2788 
2789 void InstanceKlass::print_value_on(outputStream* st) const {
2790   assert(is_klass(), "must be klass");
2791   if (Verbose || WizardMode)  access_flags().print_on(st);
2792   name()->print_value_on(st);
2793 }
2794 
2795 #ifndef PRODUCT
2796 
2797 void FieldPrinter::do_field(fieldDescriptor* fd) {
2798   _st->print(BULLET);
2799    if (_obj == NULL) {
2800      fd->print_on(_st);
2801      _st->cr();
2802    } else {
2803      fd->print_on_for(_st, _obj);
2804      _st->cr();
2805    }
2806 }
2807 
2808 
2809 void InstanceKlass::oop_print_on(oop obj, outputStream* st) {
2810   Klass::oop_print_on(obj, st);
2811 
2812   if (this == SystemDictionary::String_klass()) {
2813     typeArrayOop value  = java_lang_String::value(obj);
2814     juint        length = java_lang_String::length(obj);
2815     if (value != NULL &&
2816         value->is_typeArray() &&
2817         length <= (juint) value->length()) {
2818       st->print(BULLET"string: ");
2819       java_lang_String::print(obj, st);
2820       st->cr();
2821       if (!WizardMode)  return;  // that is enough
2822     }
2823   }
2824 
2825   st->print_cr(BULLET"---- fields (total size %d words):", oop_size(obj));
2826   FieldPrinter print_field(st, obj);
2827   do_nonstatic_fields(&print_field);
2828 
2829   if (this == SystemDictionary::Class_klass()) {
2830     st->print(BULLET"signature: ");
2831     java_lang_Class::print_signature(obj, st);
2832     st->cr();
2833     Klass* mirrored_klass = java_lang_Class::as_Klass(obj);
2834     st->print(BULLET"fake entry for mirror: ");
2835     mirrored_klass->print_value_on_maybe_null(st);
2836     st->cr();
2837     Klass* array_klass = java_lang_Class::array_klass(obj);
2838     st->print(BULLET"fake entry for array: ");
2839     array_klass->print_value_on_maybe_null(st);
2840     st->cr();
2841     st->print_cr(BULLET"fake entry for oop_size: %d", java_lang_Class::oop_size(obj));
2842     st->print_cr(BULLET"fake entry for static_oop_field_count: %d", java_lang_Class::static_oop_field_count(obj));
2843     Klass* real_klass = java_lang_Class::as_Klass(obj);
2844     if (real_klass != NULL && real_klass->is_instance_klass()) {
2845       InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field);
2846     }
2847   } else if (this == SystemDictionary::MethodType_klass()) {
2848     st->print(BULLET"signature: ");
2849     java_lang_invoke_MethodType::print_signature(obj, st);
2850     st->cr();
2851   }
2852 }
2853 
2854 #endif //PRODUCT
2855 
2856 void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) {
2857   st->print("a ");
2858   name()->print_value_on(st);
2859   obj->print_address_on(st);
2860   if (this == SystemDictionary::String_klass()
2861       && java_lang_String::value(obj) != NULL) {
2862     ResourceMark rm;
2863     int len = java_lang_String::length(obj);
2864     int plen = (len < 24 ? len : 12);
2865     char* str = java_lang_String::as_utf8_string(obj, 0, plen);
2866     st->print(" = \"%s\"", str);
2867     if (len > plen)
2868       st->print("...[%d]", len);
2869   } else if (this == SystemDictionary::Class_klass()) {
2870     Klass* k = java_lang_Class::as_Klass(obj);
2871     st->print(" = ");
2872     if (k != NULL) {
2873       k->print_value_on(st);
2874     } else {
2875       const char* tname = type2name(java_lang_Class::primitive_type(obj));
2876       st->print("%s", tname ? tname : "type?");
2877     }
2878   } else if (this == SystemDictionary::MethodType_klass()) {
2879     st->print(" = ");
2880     java_lang_invoke_MethodType::print_signature(obj, st);
2881   } else if (java_lang_boxing_object::is_instance(obj)) {
2882     st->print(" = ");
2883     java_lang_boxing_object::print(obj, st);
2884   } else if (this == SystemDictionary::LambdaForm_klass()) {
2885     oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj);
2886     if (vmentry != NULL) {
2887       st->print(" => ");
2888       vmentry->print_value_on(st);
2889     }
2890   } else if (this == SystemDictionary::MemberName_klass()) {
2891     Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj);
2892     if (vmtarget != NULL) {
2893       st->print(" = ");
2894       vmtarget->print_value_on(st);
2895     } else {
2896       java_lang_invoke_MemberName::clazz(obj)->print_value_on(st);
2897       st->print(".");
2898       java_lang_invoke_MemberName::name(obj)->print_value_on(st);
2899     }
2900   }
2901 }
2902 
2903 const char* InstanceKlass::internal_name() const {
2904   return external_name();
2905 }
2906 
2907 #if INCLUDE_SERVICES
2908 // Size Statistics
2909 void InstanceKlass::collect_statistics(KlassSizeStats *sz) const {
2910   Klass::collect_statistics(sz);
2911 
2912   sz->_inst_size  = HeapWordSize * size_helper();
2913   sz->_vtab_bytes = HeapWordSize * align_object_offset(vtable_length());
2914   sz->_itab_bytes = HeapWordSize * align_object_offset(itable_length());
2915   sz->_nonstatic_oopmap_bytes = HeapWordSize *
2916         ((is_interface() || is_anonymous()) ?
2917          align_object_offset(nonstatic_oop_map_size()) :
2918          nonstatic_oop_map_size());
2919 
2920   int n = 0;
2921   n += (sz->_methods_array_bytes         = sz->count_array(methods()));
2922   n += (sz->_method_ordering_bytes       = sz->count_array(method_ordering()));
2923   n += (sz->_local_interfaces_bytes      = sz->count_array(local_interfaces()));
2924   n += (sz->_transitive_interfaces_bytes = sz->count_array(transitive_interfaces()));
2925   n += (sz->_fields_bytes                = sz->count_array(fields()));
2926   n += (sz->_inner_classes_bytes         = sz->count_array(inner_classes()));
2927   sz->_ro_bytes += n;
2928 
2929   const ConstantPool* cp = constants();
2930   if (cp) {
2931     cp->collect_statistics(sz);
2932   }
2933 
2934   const Annotations* anno = annotations();
2935   if (anno) {
2936     anno->collect_statistics(sz);
2937   }
2938 
2939   const Array<Method*>* methods_array = methods();
2940   if (methods()) {
2941     for (int i = 0; i < methods_array->length(); i++) {
2942       Method* method = methods_array->at(i);
2943       if (method) {
2944         sz->_method_count ++;
2945         method->collect_statistics(sz);
2946       }
2947     }
2948   }
2949 }
2950 #endif // INCLUDE_SERVICES
2951 
2952 // Verification
2953 
2954 class VerifyFieldClosure: public OopClosure {
2955  protected:
2956   template <class T> void do_oop_work(T* p) {
2957     oop obj = oopDesc::load_decode_heap_oop(p);
2958     if (!obj->is_oop_or_null()) {
2959       tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p2i(p), p2i(obj));
2960       Universe::print();
2961       guarantee(false, "boom");
2962     }
2963   }
2964  public:
2965   virtual void do_oop(oop* p)       { VerifyFieldClosure::do_oop_work(p); }
2966   virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); }
2967 };
2968 
2969 void InstanceKlass::verify_on(outputStream* st) {
2970 #ifndef PRODUCT
2971   // Avoid redundant verifies, this really should be in product.
2972   if (_verify_count == Universe::verify_count()) return;
2973   _verify_count = Universe::verify_count();
2974 #endif
2975 
2976   // Verify Klass
2977   Klass::verify_on(st);
2978 
2979   // Verify that klass is present in ClassLoaderData
2980   guarantee(class_loader_data()->contains_klass(this),
2981             "this class isn't found in class loader data");
2982 
2983   // Verify vtables
2984   if (is_linked()) {
2985     ResourceMark rm;
2986     // $$$ This used to be done only for m/s collections.  Doing it
2987     // always seemed a valid generalization.  (DLD -- 6/00)
2988     vtable()->verify(st);
2989   }
2990 
2991   // Verify first subklass
2992   if (subklass() != NULL) {
2993     guarantee(subklass()->is_klass(), "should be klass");
2994   }
2995 
2996   // Verify siblings
2997   Klass* super = this->super();
2998   Klass* sib = next_sibling();
2999   if (sib != NULL) {
3000     if (sib == this) {
3001       fatal("subclass points to itself " PTR_FORMAT, p2i(sib));
3002     }
3003 
3004     guarantee(sib->is_klass(), "should be klass");
3005     guarantee(sib->super() == super, "siblings should have same superklass");
3006   }
3007 
3008   // Verify implementor fields
3009   Klass* im = implementor();
3010   if (im != NULL) {
3011     guarantee(is_interface(), "only interfaces should have implementor set");
3012     guarantee(im->is_klass(), "should be klass");
3013     guarantee(!im->is_interface() || im == this,
3014       "implementors cannot be interfaces");
3015   }
3016 
3017   // Verify local interfaces
3018   if (local_interfaces()) {
3019     Array<Klass*>* local_interfaces = this->local_interfaces();
3020     for (int j = 0; j < local_interfaces->length(); j++) {
3021       Klass* e = local_interfaces->at(j);
3022       guarantee(e->is_klass() && e->is_interface(), "invalid local interface");
3023     }
3024   }
3025 
3026   // Verify transitive interfaces
3027   if (transitive_interfaces() != NULL) {
3028     Array<Klass*>* transitive_interfaces = this->transitive_interfaces();
3029     for (int j = 0; j < transitive_interfaces->length(); j++) {
3030       Klass* e = transitive_interfaces->at(j);
3031       guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface");
3032     }
3033   }
3034 
3035   // Verify methods
3036   if (methods() != NULL) {
3037     Array<Method*>* methods = this->methods();
3038     for (int j = 0; j < methods->length(); j++) {
3039       guarantee(methods->at(j)->is_method(), "non-method in methods array");
3040     }
3041     for (int j = 0; j < methods->length() - 1; j++) {
3042       Method* m1 = methods->at(j);
3043       Method* m2 = methods->at(j + 1);
3044       guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3045     }
3046   }
3047 
3048   // Verify method ordering
3049   if (method_ordering() != NULL) {
3050     Array<int>* method_ordering = this->method_ordering();
3051     int length = method_ordering->length();
3052     if (JvmtiExport::can_maintain_original_method_order() ||
3053         ((UseSharedSpaces || DumpSharedSpaces) && length != 0)) {
3054       guarantee(length == methods()->length(), "invalid method ordering length");
3055       jlong sum = 0;
3056       for (int j = 0; j < length; j++) {
3057         int original_index = method_ordering->at(j);
3058         guarantee(original_index >= 0, "invalid method ordering index");
3059         guarantee(original_index < length, "invalid method ordering index");
3060         sum += original_index;
3061       }
3062       // Verify sum of indices 0,1,...,length-1
3063       guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum");
3064     } else {
3065       guarantee(length == 0, "invalid method ordering length");
3066     }
3067   }
3068 
3069   // Verify default methods
3070   if (default_methods() != NULL) {
3071     Array<Method*>* methods = this->default_methods();
3072     for (int j = 0; j < methods->length(); j++) {
3073       guarantee(methods->at(j)->is_method(), "non-method in methods array");
3074     }
3075     for (int j = 0; j < methods->length() - 1; j++) {
3076       Method* m1 = methods->at(j);
3077       Method* m2 = methods->at(j + 1);
3078       guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3079     }
3080   }
3081 
3082   // Verify JNI static field identifiers
3083   if (jni_ids() != NULL) {
3084     jni_ids()->verify(this);
3085   }
3086 
3087   // Verify other fields
3088   if (array_klasses() != NULL) {
3089     guarantee(array_klasses()->is_klass(), "should be klass");
3090   }
3091   if (constants() != NULL) {
3092     guarantee(constants()->is_constantPool(), "should be constant pool");
3093   }
3094   const Klass* host = host_klass();
3095   if (host != NULL) {
3096     guarantee(host->is_klass(), "should be klass");
3097   }
3098 }
3099 
3100 void InstanceKlass::oop_verify_on(oop obj, outputStream* st) {
3101   Klass::oop_verify_on(obj, st);
3102   VerifyFieldClosure blk;
3103   obj->oop_iterate_no_header(&blk);
3104 }
3105 
3106 
3107 // JNIid class for jfieldIDs only
3108 // Note to reviewers:
3109 // These JNI functions are just moved over to column 1 and not changed
3110 // in the compressed oops workspace.
3111 JNIid::JNIid(Klass* holder, int offset, JNIid* next) {
3112   _holder = holder;
3113   _offset = offset;
3114   _next = next;
3115   debug_only(_is_static_field_id = false;)
3116 }
3117 
3118 
3119 JNIid* JNIid::find(int offset) {
3120   JNIid* current = this;
3121   while (current != NULL) {
3122     if (current->offset() == offset) return current;
3123     current = current->next();
3124   }
3125   return NULL;
3126 }
3127 
3128 void JNIid::deallocate(JNIid* current) {
3129   while (current != NULL) {
3130     JNIid* next = current->next();
3131     delete current;
3132     current = next;
3133   }
3134 }
3135 
3136 
3137 void JNIid::verify(Klass* holder) {
3138   int first_field_offset  = InstanceMirrorKlass::offset_of_static_fields();
3139   int end_field_offset;
3140   end_field_offset = first_field_offset + (InstanceKlass::cast(holder)->static_field_size() * wordSize);
3141 
3142   JNIid* current = this;
3143   while (current != NULL) {
3144     guarantee(current->holder() == holder, "Invalid klass in JNIid");
3145 #ifdef ASSERT
3146     int o = current->offset();
3147     if (current->is_static_field_id()) {
3148       guarantee(o >= first_field_offset  && o < end_field_offset,  "Invalid static field offset in JNIid");
3149     }
3150 #endif
3151     current = current->next();
3152   }
3153 }
3154 
3155 
3156 #ifdef ASSERT
3157 void InstanceKlass::set_init_state(ClassState state) {
3158   bool good_state = is_shared() ? (_init_state <= state)
3159                                                : (_init_state < state);
3160   assert(good_state || state == allocated, "illegal state transition");
3161   _init_state = (u1)state;
3162 }
3163 #endif
3164 
3165 
3166 
3167 // RedefineClasses() support for previous versions:
3168 int InstanceKlass::_previous_version_count = 0;
3169 
3170 // Purge previous versions before adding new previous versions of the class.
3171 void InstanceKlass::purge_previous_versions(InstanceKlass* ik) {
3172   if (ik->previous_versions() != NULL) {
3173     // This klass has previous versions so see what we can cleanup
3174     // while it is safe to do so.
3175 
3176     int deleted_count = 0;    // leave debugging breadcrumbs
3177     int live_count = 0;
3178     ClassLoaderData* loader_data = ik->class_loader_data();
3179     assert(loader_data != NULL, "should never be null");
3180 
3181     // RC_TRACE macro has an embedded ResourceMark
3182     RC_TRACE(0x00000200, ("purge: %s: previous versions", ik->external_name()));
3183 
3184     // previous versions are linked together through the InstanceKlass
3185     InstanceKlass* pv_node = ik->previous_versions();
3186     InstanceKlass* last = ik;
3187     int version = 0;
3188 
3189     // check the previous versions list
3190     for (; pv_node != NULL; ) {
3191 
3192       ConstantPool* pvcp = pv_node->constants();
3193       assert(pvcp != NULL, "cp ref was unexpectedly cleared");
3194 
3195       if (!pvcp->on_stack()) {
3196         // If the constant pool isn't on stack, none of the methods
3197         // are executing.  Unlink this previous_version.
3198         // The previous version InstanceKlass is on the ClassLoaderData deallocate list
3199         // so will be deallocated during the next phase of class unloading.
3200         RC_TRACE(0x00000200, ("purge: previous version " INTPTR_FORMAT " is dead",
3201                               p2i(pv_node)));
3202         // For debugging purposes.
3203         pv_node->set_is_scratch_class();
3204         pv_node->class_loader_data()->add_to_deallocate_list(pv_node);
3205         pv_node = pv_node->previous_versions();
3206         last->link_previous_versions(pv_node);
3207         deleted_count++;
3208         version++;
3209         continue;
3210       } else {
3211         RC_TRACE(0x00000200, ("purge: previous version " INTPTR_FORMAT " is alive",
3212                               p2i(pv_node)));
3213         assert(pvcp->pool_holder() != NULL, "Constant pool with no holder");
3214         guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack");
3215         live_count++;
3216       }
3217 
3218       // At least one method is live in this previous version.
3219       // Reset dead EMCP methods not to get breakpoints.
3220       // All methods are deallocated when all of the methods for this class are no
3221       // longer running.
3222       Array<Method*>* method_refs = pv_node->methods();
3223       if (method_refs != NULL) {
3224         RC_TRACE(0x00000200, ("purge: previous methods length=%d",
3225           method_refs->length()));
3226         for (int j = 0; j < method_refs->length(); j++) {
3227           Method* method = method_refs->at(j);
3228 
3229           if (!method->on_stack()) {
3230             // no breakpoints for non-running methods
3231             if (method->is_running_emcp()) {
3232               method->set_running_emcp(false);
3233             }
3234           } else {
3235             assert (method->is_obsolete() || method->is_running_emcp(),
3236                     "emcp method cannot run after emcp bit is cleared");
3237             // RC_TRACE macro has an embedded ResourceMark
3238             RC_TRACE(0x00000200,
3239               ("purge: %s(%s): prev method @%d in version @%d is alive",
3240               method->name()->as_C_string(),
3241               method->signature()->as_C_string(), j, version));
3242           }
3243         }
3244       }
3245       // next previous version
3246       last = pv_node;
3247       pv_node = pv_node->previous_versions();
3248       version++;
3249     }
3250     RC_TRACE(0x00000200,
3251       ("purge: previous version stats: live=%d, deleted=%d", live_count,
3252       deleted_count));
3253   }
3254 }
3255 
3256 void InstanceKlass::mark_newly_obsolete_methods(Array<Method*>* old_methods,
3257                                                 int emcp_method_count) {
3258   int obsolete_method_count = old_methods->length() - emcp_method_count;
3259 
3260   if (emcp_method_count != 0 && obsolete_method_count != 0 &&
3261       _previous_versions != NULL) {
3262     // We have a mix of obsolete and EMCP methods so we have to
3263     // clear out any matching EMCP method entries the hard way.
3264     int local_count = 0;
3265     for (int i = 0; i < old_methods->length(); i++) {
3266       Method* old_method = old_methods->at(i);
3267       if (old_method->is_obsolete()) {
3268         // only obsolete methods are interesting
3269         Symbol* m_name = old_method->name();
3270         Symbol* m_signature = old_method->signature();
3271 
3272         // previous versions are linked together through the InstanceKlass
3273         int j = 0;
3274         for (InstanceKlass* prev_version = _previous_versions;
3275              prev_version != NULL;
3276              prev_version = prev_version->previous_versions(), j++) {
3277 
3278           Array<Method*>* method_refs = prev_version->methods();
3279           for (int k = 0; k < method_refs->length(); k++) {
3280             Method* method = method_refs->at(k);
3281 
3282             if (!method->is_obsolete() &&
3283                 method->name() == m_name &&
3284                 method->signature() == m_signature) {
3285               // The current RedefineClasses() call has made all EMCP
3286               // versions of this method obsolete so mark it as obsolete
3287               RC_TRACE(0x00000400,
3288                 ("add: %s(%s): flush obsolete method @%d in version @%d",
3289                 m_name->as_C_string(), m_signature->as_C_string(), k, j));
3290 
3291               method->set_is_obsolete();
3292               break;
3293             }
3294           }
3295 
3296           // The previous loop may not find a matching EMCP method, but
3297           // that doesn't mean that we can optimize and not go any
3298           // further back in the PreviousVersion generations. The EMCP
3299           // method for this generation could have already been made obsolete,
3300           // but there still may be an older EMCP method that has not
3301           // been made obsolete.
3302         }
3303 
3304         if (++local_count >= obsolete_method_count) {
3305           // no more obsolete methods so bail out now
3306           break;
3307         }
3308       }
3309     }
3310   }
3311 }
3312 
3313 // Save the scratch_class as the previous version if any of the methods are running.
3314 // The previous_versions are used to set breakpoints in EMCP methods and they are
3315 // also used to clean MethodData links to redefined methods that are no longer running.
3316 void InstanceKlass::add_previous_version(instanceKlassHandle scratch_class,
3317                                          int emcp_method_count) {
3318   assert(Thread::current()->is_VM_thread(),
3319          "only VMThread can add previous versions");
3320 
3321   // RC_TRACE macro has an embedded ResourceMark
3322   RC_TRACE(0x00000400, ("adding previous version ref for %s, EMCP_cnt=%d",
3323     scratch_class->external_name(), emcp_method_count));
3324 
3325   // Clean out old previous versions
3326   purge_previous_versions(this);
3327 
3328   // Mark newly obsolete methods in remaining previous versions.  An EMCP method from
3329   // a previous redefinition may be made obsolete by this redefinition.
3330   Array<Method*>* old_methods = scratch_class->methods();
3331   mark_newly_obsolete_methods(old_methods, emcp_method_count);
3332 
3333   // If the constant pool for this previous version of the class
3334   // is not marked as being on the stack, then none of the methods
3335   // in this previous version of the class are on the stack so
3336   // we don't need to add this as a previous version.
3337   ConstantPool* cp_ref = scratch_class->constants();
3338   if (!cp_ref->on_stack()) {
3339     RC_TRACE(0x00000400, ("add: scratch class not added; no methods are running"));
3340     // For debugging purposes.
3341     scratch_class->set_is_scratch_class();
3342     scratch_class->class_loader_data()->add_to_deallocate_list(scratch_class());
3343     // Update count for class unloading.
3344     _previous_version_count--;
3345     return;
3346   }
3347 
3348   if (emcp_method_count != 0) {
3349     // At least one method is still running, check for EMCP methods
3350     for (int i = 0; i < old_methods->length(); i++) {
3351       Method* old_method = old_methods->at(i);
3352       if (!old_method->is_obsolete() && old_method->on_stack()) {
3353         // if EMCP method (not obsolete) is on the stack, mark as EMCP so that
3354         // we can add breakpoints for it.
3355 
3356         // We set the method->on_stack bit during safepoints for class redefinition
3357         // and use this bit to set the is_running_emcp bit.
3358         // After the safepoint, the on_stack bit is cleared and the running emcp
3359         // method may exit.   If so, we would set a breakpoint in a method that
3360         // is never reached, but this won't be noticeable to the programmer.
3361         old_method->set_running_emcp(true);
3362         RC_TRACE(0x00000400, ("add: EMCP method %s is on_stack " INTPTR_FORMAT,
3363                               old_method->name_and_sig_as_C_string(), p2i(old_method)));
3364       } else if (!old_method->is_obsolete()) {
3365         RC_TRACE(0x00000400, ("add: EMCP method %s is NOT on_stack " INTPTR_FORMAT,
3366                               old_method->name_and_sig_as_C_string(), p2i(old_method)));
3367       }
3368     }
3369   }
3370 
3371   // Add previous version if any methods are still running.
3372   RC_TRACE(0x00000400, ("add: scratch class added; one of its methods is on_stack"));
3373   assert(scratch_class->previous_versions() == NULL, "shouldn't have a previous version");
3374   scratch_class->link_previous_versions(previous_versions());
3375   link_previous_versions(scratch_class());
3376   // Update count for class unloading.
3377   _previous_version_count++;
3378 } // end add_previous_version()
3379 
3380 
3381 Method* InstanceKlass::method_with_idnum(int idnum) {
3382   Method* m = NULL;
3383   if (idnum < methods()->length()) {
3384     m = methods()->at(idnum);
3385   }
3386   if (m == NULL || m->method_idnum() != idnum) {
3387     for (int index = 0; index < methods()->length(); ++index) {
3388       m = methods()->at(index);
3389       if (m->method_idnum() == idnum) {
3390         return m;
3391       }
3392     }
3393     // None found, return null for the caller to handle.
3394     return NULL;
3395   }
3396   return m;
3397 }
3398 
3399 
3400 Method* InstanceKlass::method_with_orig_idnum(int idnum) {
3401   if (idnum >= methods()->length()) {
3402     return NULL;
3403   }
3404   Method* m = methods()->at(idnum);
3405   if (m != NULL && m->orig_method_idnum() == idnum) {
3406     return m;
3407   }
3408   // Obsolete method idnum does not match the original idnum
3409   for (int index = 0; index < methods()->length(); ++index) {
3410     m = methods()->at(index);
3411     if (m->orig_method_idnum() == idnum) {
3412       return m;
3413     }
3414   }
3415   // None found, return null for the caller to handle.
3416   return NULL;
3417 }
3418 
3419 
3420 Method* InstanceKlass::method_with_orig_idnum(int idnum, int version) {
3421   InstanceKlass* holder = get_klass_version(version);
3422   if (holder == NULL) {
3423     return NULL; // The version of klass is gone, no method is found
3424   }
3425   Method* method = holder->method_with_orig_idnum(idnum);
3426   return method;
3427 }
3428 
3429 
3430 jint InstanceKlass::get_cached_class_file_len() {
3431   return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file);
3432 }
3433 
3434 unsigned char * InstanceKlass::get_cached_class_file_bytes() {
3435   return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file);
3436 }