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