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/shared/collectedHeap.inline.hpp"
  32 #include "gc/shared/specialized_oop_closures.hpp"
  33 #include "interpreter/oopMapCache.hpp"
  34 #include "interpreter/rewriter.hpp"
  35 #include "jvmtifiles/jvmti.h"
  36 #include "memory/heapInspection.hpp"
  37 #include "memory/iterator.inline.hpp"
  38 #include "memory/metadataFactory.hpp"
  39 #include "memory/oopFactory.hpp"
  40 #include "oops/fieldStreams.hpp"
  41 #include "oops/instanceClassLoaderKlass.hpp"
  42 #include "oops/instanceKlass.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/jvmtiRedefineClasses.hpp"
  51 #include "prims/jvmtiRedefineClassesTrace.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 #ifdef DTRACE_ENABLED
  70 
  71 
  72 #define HOTSPOT_CLASS_INITIALIZATION_required HOTSPOT_CLASS_INITIALIZATION_REQUIRED
  73 #define HOTSPOT_CLASS_INITIALIZATION_recursive HOTSPOT_CLASS_INITIALIZATION_RECURSIVE
  74 #define HOTSPOT_CLASS_INITIALIZATION_concurrent HOTSPOT_CLASS_INITIALIZATION_CONCURRENT
  75 #define HOTSPOT_CLASS_INITIALIZATION_erroneous HOTSPOT_CLASS_INITIALIZATION_ERRONEOUS
  76 #define HOTSPOT_CLASS_INITIALIZATION_super__failed HOTSPOT_CLASS_INITIALIZATION_SUPER_FAILED
  77 #define HOTSPOT_CLASS_INITIALIZATION_clinit HOTSPOT_CLASS_INITIALIZATION_CLINIT
  78 #define HOTSPOT_CLASS_INITIALIZATION_error HOTSPOT_CLASS_INITIALIZATION_ERROR
  79 #define HOTSPOT_CLASS_INITIALIZATION_end HOTSPOT_CLASS_INITIALIZATION_END
  80 #define DTRACE_CLASSINIT_PROBE(type, clss, thread_type)          \
  81   {                                                              \
  82     char* data = NULL;                                           \
  83     int len = 0;                                                 \
  84     Symbol* name = (clss)->name();                               \
  85     if (name != NULL) {                                          \
  86       data = (char*)name->bytes();                               \
  87       len = name->utf8_length();                                 \
  88     }                                                            \
  89     HOTSPOT_CLASS_INITIALIZATION_##type(                         \
  90       data, len, (clss)->class_loader(), thread_type);           \
  91   }
  92 
  93 #define DTRACE_CLASSINIT_PROBE_WAIT(type, clss, thread_type, wait) \
  94   {                                                              \
  95     char* data = NULL;                                           \
  96     int len = 0;                                                 \
  97     Symbol* name = (clss)->name();                               \
  98     if (name != NULL) {                                          \
  99       data = (char*)name->bytes();                               \
 100       len = name->utf8_length();                                 \
 101     }                                                            \
 102     HOTSPOT_CLASS_INITIALIZATION_##type(                         \
 103       data, len, (clss)->class_loader(), thread_type, wait);     \
 104   }
 105 
 106 #else //  ndef DTRACE_ENABLED
 107 
 108 #define DTRACE_CLASSINIT_PROBE(type, clss, thread_type)
 109 #define DTRACE_CLASSINIT_PROBE_WAIT(type, clss, thread_type, wait)
 110 
 111 #endif //  ndef DTRACE_ENABLED
 112 
 113 volatile int InstanceKlass::_total_instanceKlass_count = 0;
 114 
 115 InstanceKlass* InstanceKlass::allocate_instance_klass(
 116                                               ClassLoaderData* loader_data,
 117                                               int vtable_len,
 118                                               int itable_len,
 119                                               int static_field_size,
 120                                               int nonstatic_oop_map_size,
 121                                               ReferenceType rt,
 122                                               AccessFlags access_flags,
 123                                               Symbol* name,
 124                                               Klass* super_klass,
 125                                               bool is_anonymous,
 126                                               TRAPS) {
 127 
 128   int size = InstanceKlass::size(vtable_len, itable_len, nonstatic_oop_map_size,
 129                                  access_flags.is_interface(), is_anonymous);
 130 
 131   // Allocation
 132   InstanceKlass* ik;
 133   if (rt == REF_NONE) {
 134     if (name == vmSymbols::java_lang_Class()) {
 135       ik = new (loader_data, size, THREAD) InstanceMirrorKlass(
 136         vtable_len, itable_len, static_field_size, nonstatic_oop_map_size, rt,
 137         access_flags, is_anonymous);
 138     } else if (name == vmSymbols::java_lang_ClassLoader() ||
 139           (SystemDictionary::ClassLoader_klass_loaded() &&
 140           super_klass != NULL &&
 141           super_klass->is_subtype_of(SystemDictionary::ClassLoader_klass()))) {
 142       ik = new (loader_data, size, THREAD) InstanceClassLoaderKlass(
 143         vtable_len, itable_len, static_field_size, nonstatic_oop_map_size, rt,
 144         access_flags, is_anonymous);
 145     } else {
 146       // normal class
 147       ik = new (loader_data, size, THREAD) InstanceKlass(
 148         vtable_len, itable_len, static_field_size, nonstatic_oop_map_size,
 149         InstanceKlass::_misc_kind_other, rt, access_flags, is_anonymous);
 150     }
 151   } else {
 152     // reference klass
 153     ik = new (loader_data, size, THREAD) InstanceRefKlass(
 154         vtable_len, itable_len, static_field_size, nonstatic_oop_map_size, rt,
 155         access_flags, is_anonymous);
 156   }
 157 
 158   // Check for pending exception before adding to the loader data and incrementing
 159   // class count.  Can get OOM here.
 160   if (HAS_PENDING_EXCEPTION) {
 161     return NULL;
 162   }
 163 
 164   // Add all classes to our internal class loader list here,
 165   // including classes in the bootstrap (NULL) class loader.
 166   loader_data->add_class(ik);
 167 
 168   Atomic::inc(&_total_instanceKlass_count);
 169   return ik;
 170 }
 171 
 172 
 173 // copy method ordering from resource area to Metaspace
 174 void InstanceKlass::copy_method_ordering(intArray* m, TRAPS) {
 175   if (m != NULL) {
 176     // allocate a new array and copy contents (memcpy?)
 177     _method_ordering = MetadataFactory::new_array<int>(class_loader_data(), m->length(), CHECK);
 178     for (int i = 0; i < m->length(); i++) {
 179       _method_ordering->at_put(i, m->at(i));
 180     }
 181   } else {
 182     _method_ordering = Universe::the_empty_int_array();
 183   }
 184 }
 185 
 186 // create a new array of vtable_indices for default methods
 187 Array<int>* InstanceKlass::create_new_default_vtable_indices(int len, TRAPS) {
 188   Array<int>* vtable_indices = MetadataFactory::new_array<int>(class_loader_data(), len, CHECK_NULL);
 189   assert(default_vtable_indices() == NULL, "only create once");
 190   set_default_vtable_indices(vtable_indices);
 191   return vtable_indices;
 192 }
 193 
 194 InstanceKlass::InstanceKlass(int vtable_len,
 195                              int itable_len,
 196                              int static_field_size,
 197                              int nonstatic_oop_map_size,
 198                              unsigned kind,
 199                              ReferenceType rt,
 200                              AccessFlags access_flags,
 201                              bool is_anonymous) {
 202   No_Safepoint_Verifier no_safepoint; // until k becomes parsable
 203 
 204   int iksize = InstanceKlass::size(vtable_len, itable_len, nonstatic_oop_map_size,
 205                                    access_flags.is_interface(), is_anonymous);
 206 
 207   set_vtable_length(vtable_len);
 208   set_itable_length(itable_len);
 209   set_static_field_size(static_field_size);
 210   set_nonstatic_oop_map_size(nonstatic_oop_map_size);
 211   set_access_flags(access_flags);
 212   _misc_flags = 0;  // initialize to zero
 213   set_kind(kind);
 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     // Delete any cached resolution errors for the constant pool
 385     SystemDictionary::delete_resolution_error(constants());
 386 
 387     set_constants(NULL);
 388   }
 389 
 390   if (inner_classes() != NULL &&
 391       inner_classes() != Universe::the_empty_short_array() &&
 392       !inner_classes()->is_shared()) {
 393     MetadataFactory::free_array<jushort>(loader_data, inner_classes());
 394   }
 395   set_inner_classes(NULL);
 396 
 397   // We should deallocate the Annotations instance if it's not in shared spaces.
 398   if (annotations() != NULL && !annotations()->is_shared()) {
 399     MetadataFactory::free_metadata(loader_data, annotations());
 400   }
 401   set_annotations(NULL);
 402 }
 403 
 404 bool InstanceKlass::should_be_initialized() const {
 405   return !is_initialized();
 406 }
 407 
 408 klassVtable* InstanceKlass::vtable() const {
 409   return new klassVtable(this, start_of_vtable(), vtable_length() / vtableEntry::size());
 410 }
 411 
 412 klassItable* InstanceKlass::itable() const {
 413   return new klassItable(instanceKlassHandle(this));
 414 }
 415 
 416 void InstanceKlass::eager_initialize(Thread *thread) {
 417   if (!EagerInitialization) return;
 418 
 419   if (this->is_not_initialized()) {
 420     // abort if the the class has a class initializer
 421     if (this->class_initializer() != NULL) return;
 422 
 423     // abort if it is java.lang.Object (initialization is handled in genesis)
 424     Klass* super = this->super();
 425     if (super == NULL) return;
 426 
 427     // abort if the super class should be initialized
 428     if (!InstanceKlass::cast(super)->is_initialized()) return;
 429 
 430     // call body to expose the this pointer
 431     instanceKlassHandle this_k(thread, this);
 432     eager_initialize_impl(this_k);
 433   }
 434 }
 435 
 436 // JVMTI spec thinks there are signers and protection domain in the
 437 // instanceKlass.  These accessors pretend these fields are there.
 438 // The hprof specification also thinks these fields are in InstanceKlass.
 439 oop InstanceKlass::protection_domain() const {
 440   // return the protection_domain from the mirror
 441   return java_lang_Class::protection_domain(java_mirror());
 442 }
 443 
 444 // To remove these from requires an incompatible change and CCC request.
 445 objArrayOop InstanceKlass::signers() const {
 446   // return the signers from the mirror
 447   return java_lang_Class::signers(java_mirror());
 448 }
 449 
 450 oop InstanceKlass::init_lock() const {
 451   // return the init lock from the mirror
 452   oop lock = java_lang_Class::init_lock(java_mirror());
 453   // Prevent reordering with any access of initialization state
 454   OrderAccess::loadload();
 455   assert((oop)lock != NULL || !is_not_initialized(), // initialized or in_error state
 456          "only fully initialized state can have a null lock");
 457   return lock;
 458 }
 459 
 460 // Set the initialization lock to null so the object can be GC'ed.  Any racing
 461 // threads to get this lock will see a null lock and will not lock.
 462 // That's okay because they all check for initialized state after getting
 463 // the lock and return.
 464 void InstanceKlass::fence_and_clear_init_lock() {
 465   // make sure previous stores are all done, notably the init_state.
 466   OrderAccess::storestore();
 467   java_lang_Class::set_init_lock(java_mirror(), NULL);
 468   assert(!is_not_initialized(), "class must be initialized now");
 469 }
 470 
 471 void InstanceKlass::eager_initialize_impl(instanceKlassHandle this_k) {
 472   EXCEPTION_MARK;
 473   oop init_lock = this_k->init_lock();
 474   ObjectLocker ol(init_lock, THREAD, init_lock != NULL);
 475 
 476   // abort if someone beat us to the initialization
 477   if (!this_k->is_not_initialized()) return;  // note: not equivalent to is_initialized()
 478 
 479   ClassState old_state = this_k->init_state();
 480   link_class_impl(this_k, true, THREAD);
 481   if (HAS_PENDING_EXCEPTION) {
 482     CLEAR_PENDING_EXCEPTION;
 483     // Abort if linking the class throws an exception.
 484 
 485     // Use a test to avoid redundantly resetting the state if there's
 486     // no change.  Set_init_state() asserts that state changes make
 487     // progress, whereas here we might just be spinning in place.
 488     if( old_state != this_k->_init_state )
 489       this_k->set_init_state (old_state);
 490   } else {
 491     // linking successfull, mark class as initialized
 492     this_k->set_init_state (fully_initialized);
 493     this_k->fence_and_clear_init_lock();
 494     // trace
 495     if (TraceClassInitialization) {
 496       ResourceMark rm(THREAD);
 497       tty->print_cr("[Initialized %s without side effects]", this_k->external_name());
 498     }
 499   }
 500 }
 501 
 502 
 503 // See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization
 504 // process. The step comments refers to the procedure described in that section.
 505 // Note: implementation moved to static method to expose the this pointer.
 506 void InstanceKlass::initialize(TRAPS) {
 507   if (this->should_be_initialized()) {
 508     HandleMark hm(THREAD);
 509     instanceKlassHandle this_k(THREAD, this);
 510     initialize_impl(this_k, CHECK);
 511     // Note: at this point the class may be initialized
 512     //       OR it may be in the state of being initialized
 513     //       in case of recursive initialization!
 514   } else {
 515     assert(is_initialized(), "sanity check");
 516   }
 517 }
 518 
 519 
 520 bool InstanceKlass::verify_code(
 521     instanceKlassHandle this_k, bool throw_verifyerror, TRAPS) {
 522   // 1) Verify the bytecodes
 523   Verifier::Mode mode =
 524     throw_verifyerror ? Verifier::ThrowException : Verifier::NoException;
 525   return Verifier::verify(this_k, mode, this_k->should_verify_class(), THREAD);
 526 }
 527 
 528 
 529 // Used exclusively by the shared spaces dump mechanism to prevent
 530 // classes mapped into the shared regions in new VMs from appearing linked.
 531 
 532 void InstanceKlass::unlink_class() {
 533   assert(is_linked(), "must be linked");
 534   _init_state = loaded;
 535 }
 536 
 537 void InstanceKlass::link_class(TRAPS) {
 538   assert(is_loaded(), "must be loaded");
 539   if (!is_linked()) {
 540     HandleMark hm(THREAD);
 541     instanceKlassHandle this_k(THREAD, this);
 542     link_class_impl(this_k, true, CHECK);
 543   }
 544 }
 545 
 546 // Called to verify that a class can link during initialization, without
 547 // throwing a VerifyError.
 548 bool InstanceKlass::link_class_or_fail(TRAPS) {
 549   assert(is_loaded(), "must be loaded");
 550   if (!is_linked()) {
 551     HandleMark hm(THREAD);
 552     instanceKlassHandle this_k(THREAD, this);
 553     link_class_impl(this_k, false, CHECK_false);
 554   }
 555   return is_linked();
 556 }
 557 
 558 bool InstanceKlass::link_class_impl(
 559     instanceKlassHandle this_k, bool throw_verifyerror, TRAPS) {
 560   // check for error state
 561   if (this_k->is_in_error_state()) {
 562     ResourceMark rm(THREAD);
 563     THROW_MSG_(vmSymbols::java_lang_NoClassDefFoundError(),
 564                this_k->external_name(), false);
 565   }
 566   // return if already verified
 567   if (this_k->is_linked()) {
 568     return true;
 569   }
 570 
 571   // Timing
 572   // timer handles recursion
 573   assert(THREAD->is_Java_thread(), "non-JavaThread in link_class_impl");
 574   JavaThread* jt = (JavaThread*)THREAD;
 575 
 576   // link super class before linking this class
 577   instanceKlassHandle super(THREAD, this_k->super());
 578   if (super.not_null()) {
 579     if (super->is_interface()) {  // check if super class is an interface
 580       ResourceMark rm(THREAD);
 581       Exceptions::fthrow(
 582         THREAD_AND_LOCATION,
 583         vmSymbols::java_lang_IncompatibleClassChangeError(),
 584         "class %s has interface %s as super class",
 585         this_k->external_name(),
 586         super->external_name()
 587       );
 588       return false;
 589     }
 590 
 591     link_class_impl(super, throw_verifyerror, CHECK_false);
 592   }
 593 
 594   // link all interfaces implemented by this class before linking this class
 595   Array<Klass*>* interfaces = this_k->local_interfaces();
 596   int num_interfaces = interfaces->length();
 597   for (int index = 0; index < num_interfaces; index++) {
 598     HandleMark hm(THREAD);
 599     instanceKlassHandle ih(THREAD, interfaces->at(index));
 600     link_class_impl(ih, throw_verifyerror, CHECK_false);
 601   }
 602 
 603   // in case the class is linked in the process of linking its superclasses
 604   if (this_k->is_linked()) {
 605     return true;
 606   }
 607 
 608   // trace only the link time for this klass that includes
 609   // the verification time
 610   PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(),
 611                              ClassLoader::perf_class_link_selftime(),
 612                              ClassLoader::perf_classes_linked(),
 613                              jt->get_thread_stat()->perf_recursion_counts_addr(),
 614                              jt->get_thread_stat()->perf_timers_addr(),
 615                              PerfClassTraceTime::CLASS_LINK);
 616 
 617   // verification & rewriting
 618   {
 619     oop init_lock = this_k->init_lock();
 620     ObjectLocker ol(init_lock, THREAD, init_lock != NULL);
 621     // rewritten will have been set if loader constraint error found
 622     // on an earlier link attempt
 623     // don't verify or rewrite if already rewritten
 624 
 625     if (!this_k->is_linked()) {
 626       if (!this_k->is_rewritten()) {
 627         {
 628           bool verify_ok = verify_code(this_k, throw_verifyerror, THREAD);
 629           if (!verify_ok) {
 630             return false;
 631           }
 632         }
 633 
 634         // Just in case a side-effect of verify linked this class already
 635         // (which can sometimes happen since the verifier loads classes
 636         // using custom class loaders, which are free to initialize things)
 637         if (this_k->is_linked()) {
 638           return true;
 639         }
 640 
 641         // also sets rewritten
 642         this_k->rewrite_class(CHECK_false);
 643       }
 644 
 645       // relocate jsrs and link methods after they are all rewritten
 646       this_k->link_methods(CHECK_false);
 647 
 648       // Initialize the vtable and interface table after
 649       // methods have been rewritten since rewrite may
 650       // fabricate new Method*s.
 651       // also does loader constraint checking
 652       if (!this_k()->is_shared()) {
 653         ResourceMark rm(THREAD);
 654         this_k->vtable()->initialize_vtable(true, CHECK_false);
 655         this_k->itable()->initialize_itable(true, CHECK_false);
 656       }
 657 #ifdef ASSERT
 658       else {
 659         ResourceMark rm(THREAD);
 660         this_k->vtable()->verify(tty, true);
 661         // In case itable verification is ever added.
 662         // this_k->itable()->verify(tty, true);
 663       }
 664 #endif
 665       this_k->set_init_state(linked);
 666       if (JvmtiExport::should_post_class_prepare()) {
 667         Thread *thread = THREAD;
 668         assert(thread->is_Java_thread(), "thread->is_Java_thread()");
 669         JvmtiExport::post_class_prepare((JavaThread *) thread, this_k());
 670       }
 671     }
 672   }
 673   return true;
 674 }
 675 
 676 
 677 // Rewrite the byte codes of all of the methods of a class.
 678 // The rewriter must be called exactly once. Rewriting must happen after
 679 // verification but before the first method of the class is executed.
 680 void InstanceKlass::rewrite_class(TRAPS) {
 681   assert(is_loaded(), "must be loaded");
 682   instanceKlassHandle this_k(THREAD, this);
 683   if (this_k->is_rewritten()) {
 684     assert(this_k()->is_shared(), "rewriting an unshared class?");
 685     return;
 686   }
 687   Rewriter::rewrite(this_k, CHECK);
 688   this_k->set_rewritten();
 689 }
 690 
 691 // Now relocate and link method entry points after class is rewritten.
 692 // This is outside is_rewritten flag. In case of an exception, it can be
 693 // executed more than once.
 694 void InstanceKlass::link_methods(TRAPS) {
 695   int len = methods()->length();
 696   for (int i = len-1; i >= 0; i--) {
 697     methodHandle m(THREAD, methods()->at(i));
 698 
 699     // Set up method entry points for compiler and interpreter    .
 700     m->link_method(m, CHECK);
 701   }
 702 }
 703 
 704 // Eagerly initialize superinterfaces that declare default methods (concrete instance: any access)
 705 void InstanceKlass::initialize_super_interfaces(instanceKlassHandle this_k, TRAPS) {
 706   if (this_k->has_default_methods()) {
 707     for (int i = 0; i < this_k->local_interfaces()->length(); ++i) {
 708       Klass* iface = this_k->local_interfaces()->at(i);
 709       InstanceKlass* ik = InstanceKlass::cast(iface);
 710       if (ik->should_be_initialized()) {
 711         if (ik->has_default_methods()) {
 712           ik->initialize_super_interfaces(ik, THREAD);
 713         }
 714         // Only initialize() interfaces that "declare" concrete methods.
 715         // has_default_methods drives searching superinterfaces since it
 716         // means has_default_methods in its superinterface hierarchy
 717         if (!HAS_PENDING_EXCEPTION && ik->declares_default_methods()) {
 718           ik->initialize(THREAD);
 719         }
 720         if (HAS_PENDING_EXCEPTION) {
 721           Handle e(THREAD, PENDING_EXCEPTION);
 722           CLEAR_PENDING_EXCEPTION;
 723           {
 724             EXCEPTION_MARK;
 725             // Locks object, set state, and notify all waiting threads
 726             this_k->set_initialization_state_and_notify(
 727                 initialization_error, THREAD);
 728 
 729             // ignore any exception thrown, superclass initialization error is
 730             // thrown below
 731             CLEAR_PENDING_EXCEPTION;
 732           }
 733           THROW_OOP(e());
 734         }
 735       }
 736     }
 737   }
 738 }
 739 
 740 void InstanceKlass::initialize_impl(instanceKlassHandle this_k, TRAPS) {
 741   // Make sure klass is linked (verified) before initialization
 742   // A class could already be verified, since it has been reflected upon.
 743   this_k->link_class(CHECK);
 744 
 745   DTRACE_CLASSINIT_PROBE(required, this_k(), -1);
 746 
 747   bool wait = false;
 748 
 749   // refer to the JVM book page 47 for description of steps
 750   // Step 1
 751   {
 752     oop init_lock = this_k->init_lock();
 753     ObjectLocker ol(init_lock, THREAD, init_lock != NULL);
 754 
 755     Thread *self = THREAD; // it's passed the current thread
 756 
 757     // Step 2
 758     // If we were to use wait() instead of waitInterruptibly() then
 759     // we might end up throwing IE from link/symbol resolution sites
 760     // that aren't expected to throw.  This would wreak havoc.  See 6320309.
 761     while(this_k->is_being_initialized() && !this_k->is_reentrant_initialization(self)) {
 762         wait = true;
 763       ol.waitUninterruptibly(CHECK);
 764     }
 765 
 766     // Step 3
 767     if (this_k->is_being_initialized() && this_k->is_reentrant_initialization(self)) {
 768       DTRACE_CLASSINIT_PROBE_WAIT(recursive, this_k(), -1,wait);
 769       return;
 770     }
 771 
 772     // Step 4
 773     if (this_k->is_initialized()) {
 774       DTRACE_CLASSINIT_PROBE_WAIT(concurrent, this_k(), -1,wait);
 775       return;
 776     }
 777 
 778     // Step 5
 779     if (this_k->is_in_error_state()) {
 780       DTRACE_CLASSINIT_PROBE_WAIT(erroneous, this_k(), -1,wait);
 781       ResourceMark rm(THREAD);
 782       const char* desc = "Could not initialize class ";
 783       const char* className = this_k->external_name();
 784       size_t msglen = strlen(desc) + strlen(className) + 1;
 785       char* message = NEW_RESOURCE_ARRAY(char, msglen);
 786       if (NULL == message) {
 787         // Out of memory: can't create detailed error message
 788         THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), className);
 789       } else {
 790         jio_snprintf(message, msglen, "%s%s", desc, className);
 791         THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), message);
 792       }
 793     }
 794 
 795     // Step 6
 796     this_k->set_init_state(being_initialized);
 797     this_k->set_init_thread(self);
 798   }
 799 
 800   // Step 7
 801   Klass* super_klass = this_k->super();
 802   if (super_klass != NULL && !this_k->is_interface() && super_klass->should_be_initialized()) {
 803     super_klass->initialize(THREAD);
 804 
 805     if (HAS_PENDING_EXCEPTION) {
 806       Handle e(THREAD, PENDING_EXCEPTION);
 807       CLEAR_PENDING_EXCEPTION;
 808       {
 809         EXCEPTION_MARK;
 810         this_k->set_initialization_state_and_notify(initialization_error, THREAD); // Locks object, set state, and notify all waiting threads
 811         CLEAR_PENDING_EXCEPTION;   // ignore any exception thrown, superclass initialization error is thrown below
 812       }
 813       DTRACE_CLASSINIT_PROBE_WAIT(super__failed, this_k(), -1,wait);
 814       THROW_OOP(e());
 815     }
 816   }
 817 
 818   // Recursively initialize any superinterfaces that declare default methods
 819   // Only need to recurse if has_default_methods which includes declaring and
 820   // inheriting default methods
 821   if (this_k->has_default_methods()) {
 822     this_k->initialize_super_interfaces(this_k, CHECK);
 823   }
 824 
 825   // Step 8
 826   {
 827     assert(THREAD->is_Java_thread(), "non-JavaThread in initialize_impl");
 828     JavaThread* jt = (JavaThread*)THREAD;
 829     DTRACE_CLASSINIT_PROBE_WAIT(clinit, this_k(), -1,wait);
 830     // Timer includes any side effects of class initialization (resolution,
 831     // etc), but not recursive entry into call_class_initializer().
 832     PerfClassTraceTime timer(ClassLoader::perf_class_init_time(),
 833                              ClassLoader::perf_class_init_selftime(),
 834                              ClassLoader::perf_classes_inited(),
 835                              jt->get_thread_stat()->perf_recursion_counts_addr(),
 836                              jt->get_thread_stat()->perf_timers_addr(),
 837                              PerfClassTraceTime::CLASS_CLINIT);
 838     this_k->call_class_initializer(THREAD);
 839   }
 840 
 841   // Step 9
 842   if (!HAS_PENDING_EXCEPTION) {
 843     this_k->set_initialization_state_and_notify(fully_initialized, CHECK);
 844     { ResourceMark rm(THREAD);
 845       debug_only(this_k->vtable()->verify(tty, true);)
 846     }
 847   }
 848   else {
 849     // Step 10 and 11
 850     Handle e(THREAD, PENDING_EXCEPTION);
 851     CLEAR_PENDING_EXCEPTION;
 852     // JVMTI has already reported the pending exception
 853     // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
 854     JvmtiExport::clear_detected_exception((JavaThread*)THREAD);
 855     {
 856       EXCEPTION_MARK;
 857       this_k->set_initialization_state_and_notify(initialization_error, THREAD);
 858       CLEAR_PENDING_EXCEPTION;   // ignore any exception thrown, class initialization error is thrown below
 859       // JVMTI has already reported the pending exception
 860       // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
 861       JvmtiExport::clear_detected_exception((JavaThread*)THREAD);
 862     }
 863     DTRACE_CLASSINIT_PROBE_WAIT(error, this_k(), -1,wait);
 864     if (e->is_a(SystemDictionary::Error_klass())) {
 865       THROW_OOP(e());
 866     } else {
 867       JavaCallArguments args(e);
 868       THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(),
 869                 vmSymbols::throwable_void_signature(),
 870                 &args);
 871     }
 872   }
 873   DTRACE_CLASSINIT_PROBE_WAIT(end, this_k(), -1,wait);
 874 }
 875 
 876 
 877 // Note: implementation moved to static method to expose the this pointer.
 878 void InstanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) {
 879   instanceKlassHandle kh(THREAD, this);
 880   set_initialization_state_and_notify_impl(kh, state, CHECK);
 881 }
 882 
 883 void InstanceKlass::set_initialization_state_and_notify_impl(instanceKlassHandle this_k, ClassState state, TRAPS) {
 884   oop init_lock = this_k->init_lock();
 885   ObjectLocker ol(init_lock, THREAD, init_lock != NULL);
 886   this_k->set_init_state(state);
 887   this_k->fence_and_clear_init_lock();
 888   ol.notify_all(CHECK);
 889 }
 890 
 891 // The embedded _implementor field can only record one implementor.
 892 // When there are more than one implementors, the _implementor field
 893 // is set to the interface Klass* itself. Following are the possible
 894 // values for the _implementor field:
 895 //   NULL                  - no implementor
 896 //   implementor Klass*    - one implementor
 897 //   self                  - more than one implementor
 898 //
 899 // The _implementor field only exists for interfaces.
 900 void InstanceKlass::add_implementor(Klass* k) {
 901   assert(Compile_lock->owned_by_self(), "");
 902   assert(is_interface(), "not interface");
 903   // Filter out my subinterfaces.
 904   // (Note: Interfaces are never on the subklass list.)
 905   if (InstanceKlass::cast(k)->is_interface()) return;
 906 
 907   // Filter out subclasses whose supers already implement me.
 908   // (Note: CHA must walk subclasses of direct implementors
 909   // in order to locate indirect implementors.)
 910   Klass* sk = k->super();
 911   if (sk != NULL && InstanceKlass::cast(sk)->implements_interface(this))
 912     // We only need to check one immediate superclass, since the
 913     // implements_interface query looks at transitive_interfaces.
 914     // Any supers of the super have the same (or fewer) transitive_interfaces.
 915     return;
 916 
 917   Klass* ik = implementor();
 918   if (ik == NULL) {
 919     set_implementor(k);
 920   } else if (ik != this) {
 921     // There is already an implementor. Use itself as an indicator of
 922     // more than one implementors.
 923     set_implementor(this);
 924   }
 925 
 926   // The implementor also implements the transitive_interfaces
 927   for (int index = 0; index < local_interfaces()->length(); index++) {
 928     InstanceKlass::cast(local_interfaces()->at(index))->add_implementor(k);
 929   }
 930 }
 931 
 932 void InstanceKlass::init_implementor() {
 933   if (is_interface()) {
 934     set_implementor(NULL);
 935   }
 936 }
 937 
 938 
 939 void InstanceKlass::process_interfaces(Thread *thread) {
 940   // link this class into the implementors list of every interface it implements
 941   for (int i = local_interfaces()->length() - 1; i >= 0; i--) {
 942     assert(local_interfaces()->at(i)->is_klass(), "must be a klass");
 943     InstanceKlass* interf = InstanceKlass::cast(local_interfaces()->at(i));
 944     assert(interf->is_interface(), "expected interface");
 945     interf->add_implementor(this);
 946   }
 947 }
 948 
 949 bool InstanceKlass::can_be_primary_super_slow() const {
 950   if (is_interface())
 951     return false;
 952   else
 953     return Klass::can_be_primary_super_slow();
 954 }
 955 
 956 GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots) {
 957   // The secondaries are the implemented interfaces.
 958   Array<Klass*>* interfaces = transitive_interfaces();
 959   int num_secondaries = num_extra_slots + interfaces->length();
 960   if (num_secondaries == 0) {
 961     // Must share this for correct bootstrapping!
 962     set_secondary_supers(Universe::the_empty_klass_array());
 963     return NULL;
 964   } else if (num_extra_slots == 0) {
 965     // The secondary super list is exactly the same as the transitive interfaces.
 966     // Redefine classes has to be careful not to delete this!
 967     set_secondary_supers(interfaces);
 968     return NULL;
 969   } else {
 970     // Copy transitive interfaces to a temporary growable array to be constructed
 971     // into the secondary super list with extra slots.
 972     GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length());
 973     for (int i = 0; i < interfaces->length(); i++) {
 974       secondaries->push(interfaces->at(i));
 975     }
 976     return secondaries;
 977   }
 978 }
 979 
 980 bool InstanceKlass::compute_is_subtype_of(Klass* k) {
 981   if (k->is_interface()) {
 982     return implements_interface(k);
 983   } else {
 984     return Klass::compute_is_subtype_of(k);
 985   }
 986 }
 987 
 988 bool InstanceKlass::implements_interface(Klass* k) const {
 989   if (this == k) return true;
 990   assert(k->is_interface(), "should be an interface class");
 991   for (int i = 0; i < transitive_interfaces()->length(); i++) {
 992     if (transitive_interfaces()->at(i) == k) {
 993       return true;
 994     }
 995   }
 996   return false;
 997 }
 998 
 999 bool InstanceKlass::is_same_or_direct_interface(Klass *k) const {
1000   // Verify direct super interface
1001   if (this == k) return true;
1002   assert(k->is_interface(), "should be an interface class");
1003   for (int i = 0; i < local_interfaces()->length(); i++) {
1004     if (local_interfaces()->at(i) == k) {
1005       return true;
1006     }
1007   }
1008   return false;
1009 }
1010 
1011 objArrayOop InstanceKlass::allocate_objArray(int n, int length, TRAPS) {
1012   if (length < 0) THROW_0(vmSymbols::java_lang_NegativeArraySizeException());
1013   if (length > arrayOopDesc::max_array_length(T_OBJECT)) {
1014     report_java_out_of_memory("Requested array size exceeds VM limit");
1015     JvmtiExport::post_array_size_exhausted();
1016     THROW_OOP_0(Universe::out_of_memory_error_array_size());
1017   }
1018   int size = objArrayOopDesc::object_size(length);
1019   Klass* ak = array_klass(n, CHECK_NULL);
1020   KlassHandle h_ak (THREAD, ak);
1021   objArrayOop o =
1022     (objArrayOop)CollectedHeap::array_allocate(h_ak, size, length, CHECK_NULL);
1023   return o;
1024 }
1025 
1026 instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) {
1027   if (TraceFinalizerRegistration) {
1028     tty->print("Registered ");
1029     i->print_value_on(tty);
1030     tty->print_cr(" (" INTPTR_FORMAT ") as finalizable", p2i(i));
1031   }
1032   instanceHandle h_i(THREAD, i);
1033   // Pass the handle as argument, JavaCalls::call expects oop as jobjects
1034   JavaValue result(T_VOID);
1035   JavaCallArguments args(h_i);
1036   methodHandle mh (THREAD, Universe::finalizer_register_method());
1037   JavaCalls::call(&result, mh, &args, CHECK_NULL);
1038   return h_i();
1039 }
1040 
1041 instanceOop InstanceKlass::allocate_instance(TRAPS) {
1042   bool has_finalizer_flag = has_finalizer(); // Query before possible GC
1043   int size = size_helper();  // Query before forming handle.
1044 
1045   KlassHandle h_k(THREAD, this);
1046 
1047   instanceOop i;
1048 
1049   i = (instanceOop)CollectedHeap::obj_allocate(h_k, size, CHECK_NULL);
1050   if (has_finalizer_flag && !RegisterFinalizersAtInit) {
1051     i = register_finalizer(i, CHECK_NULL);
1052   }
1053   return i;
1054 }
1055 
1056 void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) {
1057   if (is_interface() || is_abstract()) {
1058     ResourceMark rm(THREAD);
1059     THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
1060               : vmSymbols::java_lang_InstantiationException(), external_name());
1061   }
1062   if (this == SystemDictionary::Class_klass()) {
1063     ResourceMark rm(THREAD);
1064     THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError()
1065               : vmSymbols::java_lang_IllegalAccessException(), external_name());
1066   }
1067 }
1068 
1069 Klass* InstanceKlass::array_klass_impl(bool or_null, int n, TRAPS) {
1070   instanceKlassHandle this_k(THREAD, this);
1071   return array_klass_impl(this_k, or_null, n, THREAD);
1072 }
1073 
1074 Klass* InstanceKlass::array_klass_impl(instanceKlassHandle this_k, bool or_null, int n, TRAPS) {
1075   if (this_k->array_klasses() == NULL) {
1076     if (or_null) return NULL;
1077 
1078     ResourceMark rm;
1079     JavaThread *jt = (JavaThread *)THREAD;
1080     {
1081       // Atomic creation of array_klasses
1082       MutexLocker mc(Compile_lock, THREAD);   // for vtables
1083       MutexLocker ma(MultiArray_lock, THREAD);
1084 
1085       // Check if update has already taken place
1086       if (this_k->array_klasses() == NULL) {
1087         Klass*    k = ObjArrayKlass::allocate_objArray_klass(this_k->class_loader_data(), 1, this_k, CHECK_NULL);
1088         this_k->set_array_klasses(k);
1089       }
1090     }
1091   }
1092   // _this will always be set at this point
1093   ObjArrayKlass* oak = (ObjArrayKlass*)this_k->array_klasses();
1094   if (or_null) {
1095     return oak->array_klass_or_null(n);
1096   }
1097   return oak->array_klass(n, THREAD);
1098 }
1099 
1100 Klass* InstanceKlass::array_klass_impl(bool or_null, TRAPS) {
1101   return array_klass_impl(or_null, 1, THREAD);
1102 }
1103 
1104 void InstanceKlass::call_class_initializer(TRAPS) {
1105   instanceKlassHandle ik (THREAD, this);
1106   call_class_initializer_impl(ik, THREAD);
1107 }
1108 
1109 static int call_class_initializer_impl_counter = 0;   // for debugging
1110 
1111 Method* InstanceKlass::class_initializer() {
1112   Method* clinit = find_method(
1113       vmSymbols::class_initializer_name(), vmSymbols::void_method_signature());
1114   if (clinit != NULL && clinit->has_valid_initializer_flags()) {
1115     return clinit;
1116   }
1117   return NULL;
1118 }
1119 
1120 void InstanceKlass::call_class_initializer_impl(instanceKlassHandle this_k, TRAPS) {
1121   if (ReplayCompiles &&
1122       (ReplaySuppressInitializers == 1 ||
1123        ReplaySuppressInitializers >= 2 && this_k->class_loader() != NULL)) {
1124     // Hide the existence of the initializer for the purpose of replaying the compile
1125     return;
1126   }
1127 
1128   methodHandle h_method(THREAD, this_k->class_initializer());
1129   assert(!this_k->is_initialized(), "we cannot initialize twice");
1130   if (TraceClassInitialization) {
1131     tty->print("%d Initializing ", call_class_initializer_impl_counter++);
1132     this_k->name()->print_value();
1133     tty->print_cr("%s (" INTPTR_FORMAT ")", h_method() == NULL ? "(no method)" : "", p2i(this_k()));
1134   }
1135   if (h_method() != NULL) {
1136     JavaCallArguments args; // No arguments
1137     JavaValue result(T_VOID);
1138     JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args)
1139   }
1140 }
1141 
1142 
1143 void InstanceKlass::mask_for(const methodHandle& method, int bci,
1144   InterpreterOopMap* entry_for) {
1145   // Dirty read, then double-check under a lock.
1146   if (_oop_map_cache == NULL) {
1147     // Otherwise, allocate a new one.
1148     MutexLocker x(OopMapCacheAlloc_lock);
1149     // First time use. Allocate a cache in C heap
1150     if (_oop_map_cache == NULL) {
1151       // Release stores from OopMapCache constructor before assignment
1152       // to _oop_map_cache. C++ compilers on ppc do not emit the
1153       // required memory barrier only because of the volatile
1154       // qualifier of _oop_map_cache.
1155       OrderAccess::release_store_ptr(&_oop_map_cache, new OopMapCache());
1156     }
1157   }
1158   // _oop_map_cache is constant after init; lookup below does is own locking.
1159   _oop_map_cache->lookup(method, bci, entry_for);
1160 }
1161 
1162 
1163 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1164   for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1165     Symbol* f_name = fs.name();
1166     Symbol* f_sig  = fs.signature();
1167     if (f_name == name && f_sig == sig) {
1168       fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1169       return true;
1170     }
1171   }
1172   return false;
1173 }
1174 
1175 
1176 Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1177   const int n = local_interfaces()->length();
1178   for (int i = 0; i < n; i++) {
1179     Klass* intf1 = local_interfaces()->at(i);
1180     assert(intf1->is_interface(), "just checking type");
1181     // search for field in current interface
1182     if (InstanceKlass::cast(intf1)->find_local_field(name, sig, fd)) {
1183       assert(fd->is_static(), "interface field must be static");
1184       return intf1;
1185     }
1186     // search for field in direct superinterfaces
1187     Klass* intf2 = InstanceKlass::cast(intf1)->find_interface_field(name, sig, fd);
1188     if (intf2 != NULL) return intf2;
1189   }
1190   // otherwise field lookup fails
1191   return NULL;
1192 }
1193 
1194 
1195 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1196   // search order according to newest JVM spec (5.4.3.2, p.167).
1197   // 1) search for field in current klass
1198   if (find_local_field(name, sig, fd)) {
1199     return const_cast<InstanceKlass*>(this);
1200   }
1201   // 2) search for field recursively in direct superinterfaces
1202   { Klass* intf = find_interface_field(name, sig, fd);
1203     if (intf != NULL) return intf;
1204   }
1205   // 3) apply field lookup recursively if superclass exists
1206   { Klass* supr = super();
1207     if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, fd);
1208   }
1209   // 4) otherwise field lookup fails
1210   return NULL;
1211 }
1212 
1213 
1214 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const {
1215   // search order according to newest JVM spec (5.4.3.2, p.167).
1216   // 1) search for field in current klass
1217   if (find_local_field(name, sig, fd)) {
1218     if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this);
1219   }
1220   // 2) search for field recursively in direct superinterfaces
1221   if (is_static) {
1222     Klass* intf = find_interface_field(name, sig, fd);
1223     if (intf != NULL) return intf;
1224   }
1225   // 3) apply field lookup recursively if superclass exists
1226   { Klass* supr = super();
1227     if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, is_static, fd);
1228   }
1229   // 4) otherwise field lookup fails
1230   return NULL;
1231 }
1232 
1233 
1234 bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1235   for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1236     if (fs.offset() == offset) {
1237       fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1238       if (fd->is_static() == is_static) return true;
1239     }
1240   }
1241   return false;
1242 }
1243 
1244 
1245 bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1246   Klass* klass = const_cast<InstanceKlass*>(this);
1247   while (klass != NULL) {
1248     if (InstanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) {
1249       return true;
1250     }
1251     klass = klass->super();
1252   }
1253   return false;
1254 }
1255 
1256 
1257 void InstanceKlass::methods_do(void f(Method* method)) {
1258   // Methods aren't stable until they are loaded.  This can be read outside
1259   // a lock through the ClassLoaderData for profiling
1260   if (!is_loaded()) {
1261     return;
1262   }
1263 
1264   int len = methods()->length();
1265   for (int index = 0; index < len; index++) {
1266     Method* m = methods()->at(index);
1267     assert(m->is_method(), "must be method");
1268     f(m);
1269   }
1270 }
1271 
1272 
1273 void InstanceKlass::do_local_static_fields(FieldClosure* cl) {
1274   for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1275     if (fs.access_flags().is_static()) {
1276       fieldDescriptor& fd = fs.field_descriptor();
1277       cl->do_field(&fd);
1278     }
1279   }
1280 }
1281 
1282 
1283 void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle mirror, TRAPS) {
1284   instanceKlassHandle h_this(THREAD, this);
1285   do_local_static_fields_impl(h_this, f, mirror, CHECK);
1286 }
1287 
1288 
1289 void InstanceKlass::do_local_static_fields_impl(instanceKlassHandle this_k,
1290                              void f(fieldDescriptor* fd, Handle, TRAPS), Handle mirror, TRAPS) {
1291   for (JavaFieldStream fs(this_k()); !fs.done(); fs.next()) {
1292     if (fs.access_flags().is_static()) {
1293       fieldDescriptor& fd = fs.field_descriptor();
1294       f(&fd, mirror, CHECK);
1295     }
1296   }
1297 }
1298 
1299 
1300 static int compare_fields_by_offset(int* a, int* b) {
1301   return a[0] - b[0];
1302 }
1303 
1304 void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) {
1305   InstanceKlass* super = superklass();
1306   if (super != NULL) {
1307     super->do_nonstatic_fields(cl);
1308   }
1309   fieldDescriptor fd;
1310   int length = java_fields_count();
1311   // In DebugInfo nonstatic fields are sorted by offset.
1312   int* fields_sorted = NEW_C_HEAP_ARRAY(int, 2*(length+1), mtClass);
1313   int j = 0;
1314   for (int i = 0; i < length; i += 1) {
1315     fd.reinitialize(this, i);
1316     if (!fd.is_static()) {
1317       fields_sorted[j + 0] = fd.offset();
1318       fields_sorted[j + 1] = i;
1319       j += 2;
1320     }
1321   }
1322   if (j > 0) {
1323     length = j;
1324     // _sort_Fn is defined in growableArray.hpp.
1325     qsort(fields_sorted, length/2, 2*sizeof(int), (_sort_Fn)compare_fields_by_offset);
1326     for (int i = 0; i < length; i += 2) {
1327       fd.reinitialize(this, fields_sorted[i + 1]);
1328       assert(!fd.is_static() && fd.offset() == fields_sorted[i], "only nonstatic fields");
1329       cl->do_field(&fd);
1330     }
1331   }
1332   FREE_C_HEAP_ARRAY(int, fields_sorted);
1333 }
1334 
1335 
1336 void InstanceKlass::array_klasses_do(void f(Klass* k, TRAPS), TRAPS) {
1337   if (array_klasses() != NULL)
1338     ArrayKlass::cast(array_klasses())->array_klasses_do(f, THREAD);
1339 }
1340 
1341 void InstanceKlass::array_klasses_do(void f(Klass* k)) {
1342   if (array_klasses() != NULL)
1343     ArrayKlass::cast(array_klasses())->array_klasses_do(f);
1344 }
1345 
1346 #ifdef ASSERT
1347 static int linear_search(Array<Method*>* methods, Symbol* name, Symbol* signature) {
1348   int len = methods->length();
1349   for (int index = 0; index < len; index++) {
1350     Method* m = methods->at(index);
1351     assert(m->is_method(), "must be method");
1352     if (m->signature() == signature && m->name() == name) {
1353        return index;
1354     }
1355   }
1356   return -1;
1357 }
1358 #endif
1359 
1360 static int binary_search(Array<Method*>* methods, Symbol* name) {
1361   int len = methods->length();
1362   // methods are sorted, so do binary search
1363   int l = 0;
1364   int h = len - 1;
1365   while (l <= h) {
1366     int mid = (l + h) >> 1;
1367     Method* m = methods->at(mid);
1368     assert(m->is_method(), "must be method");
1369     int res = m->name()->fast_compare(name);
1370     if (res == 0) {
1371       return mid;
1372     } else if (res < 0) {
1373       l = mid + 1;
1374     } else {
1375       h = mid - 1;
1376     }
1377   }
1378   return -1;
1379 }
1380 
1381 // find_method looks up the name/signature in the local methods array
1382 Method* InstanceKlass::find_method(Symbol* name, Symbol* signature) const {
1383   return find_method_impl(name, signature, find_overpass, find_static, find_private);
1384 }
1385 
1386 Method* InstanceKlass::find_method_impl(Symbol* name, Symbol* signature,
1387                                         OverpassLookupMode overpass_mode,
1388                                         StaticLookupMode static_mode,
1389                                         PrivateLookupMode private_mode) const {
1390   return InstanceKlass::find_method_impl(methods(), name, signature, overpass_mode, static_mode, private_mode);
1391 }
1392 
1393 // find_instance_method looks up the name/signature in the local methods array
1394 // and skips over static methods
1395 Method* InstanceKlass::find_instance_method(
1396     Array<Method*>* methods, Symbol* name, Symbol* signature) {
1397   Method* meth = InstanceKlass::find_method_impl(methods, name, signature,
1398                                                  find_overpass, skip_static, find_private);
1399   assert(((meth == NULL) || !meth->is_static()), "find_instance_method should have skipped statics");
1400   return meth;
1401 }
1402 
1403 // find_instance_method looks up the name/signature in the local methods array
1404 // and skips over static methods
1405 Method* InstanceKlass::find_instance_method(Symbol* name, Symbol* signature) {
1406     return InstanceKlass::find_instance_method(methods(), name, signature);
1407 }
1408 
1409 // Find looks up the name/signature in the local methods array
1410 // and filters on the overpass, static and private flags
1411 // This returns the first one found
1412 // note that the local methods array can have up to one overpass, one static
1413 // and one instance (private or not) with the same name/signature
1414 Method* InstanceKlass::find_local_method(Symbol* name, Symbol* signature,
1415                                         OverpassLookupMode overpass_mode,
1416                                         StaticLookupMode static_mode,
1417                                         PrivateLookupMode private_mode) const {
1418   return InstanceKlass::find_method_impl(methods(), name, signature, overpass_mode, static_mode, private_mode);
1419 }
1420 
1421 // Find looks up the name/signature in the local methods array
1422 // and filters on the overpass, static and private flags
1423 // This returns the first one found
1424 // note that the local methods array can have up to one overpass, one static
1425 // and one instance (private or not) with the same name/signature
1426 Method* InstanceKlass::find_local_method(Array<Method*>* methods,
1427                                         Symbol* name, Symbol* signature,
1428                                         OverpassLookupMode overpass_mode,
1429                                         StaticLookupMode static_mode,
1430                                         PrivateLookupMode private_mode) {
1431   return InstanceKlass::find_method_impl(methods, name, signature, overpass_mode, static_mode, private_mode);
1432 }
1433 
1434 
1435 // find_method looks up the name/signature in the local methods array
1436 Method* InstanceKlass::find_method(
1437     Array<Method*>* methods, Symbol* name, Symbol* signature) {
1438   return InstanceKlass::find_method_impl(methods, name, signature, find_overpass, find_static, find_private);
1439 }
1440 
1441 Method* InstanceKlass::find_method_impl(
1442     Array<Method*>* methods, Symbol* name, Symbol* signature,
1443     OverpassLookupMode overpass_mode, StaticLookupMode static_mode,
1444     PrivateLookupMode private_mode) {
1445   int hit = find_method_index(methods, name, signature, overpass_mode, static_mode, private_mode);
1446   return hit >= 0 ? methods->at(hit): NULL;
1447 }
1448 
1449 bool InstanceKlass::method_matches(Method* m, Symbol* signature, bool skipping_overpass, bool skipping_static, bool skipping_private) {
1450     return  ((m->signature() == signature) &&
1451             (!skipping_overpass || !m->is_overpass()) &&
1452             (!skipping_static || !m->is_static()) &&
1453             (!skipping_private || !m->is_private()));
1454 }
1455 
1456 // Used directly for default_methods to find the index into the
1457 // default_vtable_indices, and indirectly by find_method
1458 // find_method_index looks in the local methods array to return the index
1459 // of the matching name/signature. If, overpass methods are being ignored,
1460 // the search continues to find a potential non-overpass match.  This capability
1461 // is important during method resolution to prefer a static method, for example,
1462 // over an overpass method.
1463 // There is the possibility in any _method's array to have the same name/signature
1464 // for a static method, an overpass method and a local instance method
1465 // To correctly catch a given method, the search criteria may need
1466 // to explicitly skip the other two. For local instance methods, it
1467 // is often necessary to skip private methods
1468 int InstanceKlass::find_method_index(
1469     Array<Method*>* methods, Symbol* name, Symbol* signature,
1470     OverpassLookupMode overpass_mode, StaticLookupMode static_mode,
1471     PrivateLookupMode private_mode) {
1472   bool skipping_overpass = (overpass_mode == skip_overpass);
1473   bool skipping_static = (static_mode == skip_static);
1474   bool skipping_private = (private_mode == skip_private);
1475   int hit = binary_search(methods, name);
1476   if (hit != -1) {
1477     Method* m = methods->at(hit);
1478 
1479     // Do linear search to find matching signature.  First, quick check
1480     // for common case, ignoring overpasses if requested.
1481     if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) return hit;
1482 
1483     // search downwards through overloaded methods
1484     int i;
1485     for (i = hit - 1; i >= 0; --i) {
1486         Method* m = methods->at(i);
1487         assert(m->is_method(), "must be method");
1488         if (m->name() != name) break;
1489         if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) return i;
1490     }
1491     // search upwards
1492     for (i = hit + 1; i < methods->length(); ++i) {
1493         Method* m = methods->at(i);
1494         assert(m->is_method(), "must be method");
1495         if (m->name() != name) break;
1496         if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) return i;
1497     }
1498     // not found
1499 #ifdef ASSERT
1500     int index = (skipping_overpass || skipping_static || skipping_private) ? -1 : linear_search(methods, name, signature);
1501     assert(index == -1, "binary search should have found entry %d", index);
1502 #endif
1503   }
1504   return -1;
1505 }
1506 int InstanceKlass::find_method_by_name(Symbol* name, int* end) {
1507   return find_method_by_name(methods(), name, end);
1508 }
1509 
1510 int InstanceKlass::find_method_by_name(
1511     Array<Method*>* methods, Symbol* name, int* end_ptr) {
1512   assert(end_ptr != NULL, "just checking");
1513   int start = binary_search(methods, name);
1514   int end = start + 1;
1515   if (start != -1) {
1516     while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start;
1517     while (end < methods->length() && (methods->at(end))->name() == name) ++end;
1518     *end_ptr = end;
1519     return start;
1520   }
1521   return -1;
1522 }
1523 
1524 // uncached_lookup_method searches both the local class methods array and all
1525 // superclasses methods arrays, skipping any overpass methods in superclasses.
1526 Method* InstanceKlass::uncached_lookup_method(Symbol* name, Symbol* signature, OverpassLookupMode overpass_mode) const {
1527   OverpassLookupMode overpass_local_mode = overpass_mode;
1528   Klass* klass = const_cast<InstanceKlass*>(this);
1529   while (klass != NULL) {
1530     Method* method = InstanceKlass::cast(klass)->find_method_impl(name, signature, overpass_local_mode, find_static, find_private);
1531     if (method != NULL) {
1532       return method;
1533     }
1534     klass = klass->super();
1535     overpass_local_mode = skip_overpass;   // Always ignore overpass methods in superclasses
1536   }
1537   return NULL;
1538 }
1539 
1540 #ifdef ASSERT
1541 // search through class hierarchy and return true if this class or
1542 // one of the superclasses was redefined
1543 bool InstanceKlass::has_redefined_this_or_super() {
1544   Klass* klass = this;
1545   while (klass != NULL) {
1546     if (InstanceKlass::cast(klass)->has_been_redefined()) {
1547       return true;
1548     }
1549     klass = klass->super();
1550   }
1551   return false;
1552 }
1553 #endif
1554 
1555 // lookup a method in the default methods list then in all transitive interfaces
1556 // Do NOT return private or static methods
1557 Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name,
1558                                                          Symbol* signature) const {
1559   Method* m = NULL;
1560   if (default_methods() != NULL) {
1561     m = find_method(default_methods(), name, signature);
1562   }
1563   // Look up interfaces
1564   if (m == NULL) {
1565     m = lookup_method_in_all_interfaces(name, signature, find_defaults);
1566   }
1567   return m;
1568 }
1569 
1570 // lookup a method in all the interfaces that this class implements
1571 // Do NOT return private or static methods, new in JDK8 which are not externally visible
1572 // They should only be found in the initial InterfaceMethodRef
1573 Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name,
1574                                                        Symbol* signature,
1575                                                        DefaultsLookupMode defaults_mode) const {
1576   Array<Klass*>* all_ifs = transitive_interfaces();
1577   int num_ifs = all_ifs->length();
1578   InstanceKlass *ik = NULL;
1579   for (int i = 0; i < num_ifs; i++) {
1580     ik = InstanceKlass::cast(all_ifs->at(i));
1581     Method* m = ik->lookup_method(name, signature);
1582     if (m != NULL && m->is_public() && !m->is_static() &&
1583         ((defaults_mode != skip_defaults) || !m->is_default_method())) {
1584       return m;
1585     }
1586   }
1587   return NULL;
1588 }
1589 
1590 /* jni_id_for_impl for jfieldIds only */
1591 JNIid* InstanceKlass::jni_id_for_impl(instanceKlassHandle this_k, int offset) {
1592   MutexLocker ml(JfieldIdCreation_lock);
1593   // Retry lookup after we got the lock
1594   JNIid* probe = this_k->jni_ids() == NULL ? NULL : this_k->jni_ids()->find(offset);
1595   if (probe == NULL) {
1596     // Slow case, allocate new static field identifier
1597     probe = new JNIid(this_k(), offset, this_k->jni_ids());
1598     this_k->set_jni_ids(probe);
1599   }
1600   return probe;
1601 }
1602 
1603 
1604 /* jni_id_for for jfieldIds only */
1605 JNIid* InstanceKlass::jni_id_for(int offset) {
1606   JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset);
1607   if (probe == NULL) {
1608     probe = jni_id_for_impl(this, offset);
1609   }
1610   return probe;
1611 }
1612 
1613 u2 InstanceKlass::enclosing_method_data(int offset) {
1614   Array<jushort>* inner_class_list = inner_classes();
1615   if (inner_class_list == NULL) {
1616     return 0;
1617   }
1618   int length = inner_class_list->length();
1619   if (length % inner_class_next_offset == 0) {
1620     return 0;
1621   } else {
1622     int index = length - enclosing_method_attribute_size;
1623     assert(offset < enclosing_method_attribute_size, "invalid offset");
1624     return inner_class_list->at(index + offset);
1625   }
1626 }
1627 
1628 void InstanceKlass::set_enclosing_method_indices(u2 class_index,
1629                                                  u2 method_index) {
1630   Array<jushort>* inner_class_list = inner_classes();
1631   assert (inner_class_list != NULL, "_inner_classes list is not set up");
1632   int length = inner_class_list->length();
1633   if (length % inner_class_next_offset == enclosing_method_attribute_size) {
1634     int index = length - enclosing_method_attribute_size;
1635     inner_class_list->at_put(
1636       index + enclosing_method_class_index_offset, class_index);
1637     inner_class_list->at_put(
1638       index + enclosing_method_method_index_offset, method_index);
1639   }
1640 }
1641 
1642 // Lookup or create a jmethodID.
1643 // This code is called by the VMThread and JavaThreads so the
1644 // locking has to be done very carefully to avoid deadlocks
1645 // and/or other cache consistency problems.
1646 //
1647 jmethodID InstanceKlass::get_jmethod_id(instanceKlassHandle ik_h, const methodHandle& method_h) {
1648   size_t idnum = (size_t)method_h->method_idnum();
1649   jmethodID* jmeths = ik_h->methods_jmethod_ids_acquire();
1650   size_t length = 0;
1651   jmethodID id = NULL;
1652 
1653   // We use a double-check locking idiom here because this cache is
1654   // performance sensitive. In the normal system, this cache only
1655   // transitions from NULL to non-NULL which is safe because we use
1656   // release_set_methods_jmethod_ids() to advertise the new cache.
1657   // A partially constructed cache should never be seen by a racing
1658   // thread. We also use release_store_ptr() to save a new jmethodID
1659   // in the cache so a partially constructed jmethodID should never be
1660   // seen either. Cache reads of existing jmethodIDs proceed without a
1661   // lock, but cache writes of a new jmethodID requires uniqueness and
1662   // creation of the cache itself requires no leaks so a lock is
1663   // generally acquired in those two cases.
1664   //
1665   // If the RedefineClasses() API has been used, then this cache can
1666   // grow and we'll have transitions from non-NULL to bigger non-NULL.
1667   // Cache creation requires no leaks and we require safety between all
1668   // cache accesses and freeing of the old cache so a lock is generally
1669   // acquired when the RedefineClasses() API has been used.
1670 
1671   if (jmeths != NULL) {
1672     // the cache already exists
1673     if (!ik_h->idnum_can_increment()) {
1674       // the cache can't grow so we can just get the current values
1675       get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1676     } else {
1677       // cache can grow so we have to be more careful
1678       if (Threads::number_of_threads() == 0 ||
1679           SafepointSynchronize::is_at_safepoint()) {
1680         // we're single threaded or at a safepoint - no locking needed
1681         get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1682       } else {
1683         MutexLocker ml(JmethodIdCreation_lock);
1684         get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1685       }
1686     }
1687   }
1688   // implied else:
1689   // we need to allocate a cache so default length and id values are good
1690 
1691   if (jmeths == NULL ||   // no cache yet
1692       length <= idnum ||  // cache is too short
1693       id == NULL) {       // cache doesn't contain entry
1694 
1695     // This function can be called by the VMThread so we have to do all
1696     // things that might block on a safepoint before grabbing the lock.
1697     // Otherwise, we can deadlock with the VMThread or have a cache
1698     // consistency issue. These vars keep track of what we might have
1699     // to free after the lock is dropped.
1700     jmethodID  to_dealloc_id     = NULL;
1701     jmethodID* to_dealloc_jmeths = NULL;
1702 
1703     // may not allocate new_jmeths or use it if we allocate it
1704     jmethodID* new_jmeths = NULL;
1705     if (length <= idnum) {
1706       // allocate a new cache that might be used
1707       size_t size = MAX2(idnum+1, (size_t)ik_h->idnum_allocated_count());
1708       new_jmeths = NEW_C_HEAP_ARRAY(jmethodID, size+1, mtClass);
1709       memset(new_jmeths, 0, (size+1)*sizeof(jmethodID));
1710       // cache size is stored in element[0], other elements offset by one
1711       new_jmeths[0] = (jmethodID)size;
1712     }
1713 
1714     // allocate a new jmethodID that might be used
1715     jmethodID new_id = NULL;
1716     if (method_h->is_old() && !method_h->is_obsolete()) {
1717       // The method passed in is old (but not obsolete), we need to use the current version
1718       Method* current_method = ik_h->method_with_idnum((int)idnum);
1719       assert(current_method != NULL, "old and but not obsolete, so should exist");
1720       new_id = Method::make_jmethod_id(ik_h->class_loader_data(), current_method);
1721     } else {
1722       // It is the current version of the method or an obsolete method,
1723       // use the version passed in
1724       new_id = Method::make_jmethod_id(ik_h->class_loader_data(), method_h());
1725     }
1726 
1727     if (Threads::number_of_threads() == 0 ||
1728         SafepointSynchronize::is_at_safepoint()) {
1729       // we're single threaded or at a safepoint - no locking needed
1730       id = get_jmethod_id_fetch_or_update(ik_h, idnum, new_id, new_jmeths,
1731                                           &to_dealloc_id, &to_dealloc_jmeths);
1732     } else {
1733       MutexLocker ml(JmethodIdCreation_lock);
1734       id = get_jmethod_id_fetch_or_update(ik_h, idnum, new_id, new_jmeths,
1735                                           &to_dealloc_id, &to_dealloc_jmeths);
1736     }
1737 
1738     // The lock has been dropped so we can free resources.
1739     // Free up either the old cache or the new cache if we allocated one.
1740     if (to_dealloc_jmeths != NULL) {
1741       FreeHeap(to_dealloc_jmeths);
1742     }
1743     // free up the new ID since it wasn't needed
1744     if (to_dealloc_id != NULL) {
1745       Method::destroy_jmethod_id(ik_h->class_loader_data(), to_dealloc_id);
1746     }
1747   }
1748   return id;
1749 }
1750 
1751 // Figure out how many jmethodIDs haven't been allocated, and make
1752 // sure space for them is pre-allocated.  This makes getting all
1753 // method ids much, much faster with classes with more than 8
1754 // methods, and has a *substantial* effect on performance with jvmti
1755 // code that loads all jmethodIDs for all classes.
1756 void InstanceKlass::ensure_space_for_methodids(int start_offset) {
1757   int new_jmeths = 0;
1758   int length = methods()->length();
1759   for (int index = start_offset; index < length; index++) {
1760     Method* m = methods()->at(index);
1761     jmethodID id = m->find_jmethod_id_or_null();
1762     if (id == NULL) {
1763       new_jmeths++;
1764     }
1765   }
1766   if (new_jmeths != 0) {
1767     Method::ensure_jmethod_ids(class_loader_data(), new_jmeths);
1768   }
1769 }
1770 
1771 // Common code to fetch the jmethodID from the cache or update the
1772 // cache with the new jmethodID. This function should never do anything
1773 // that causes the caller to go to a safepoint or we can deadlock with
1774 // the VMThread or have cache consistency issues.
1775 //
1776 jmethodID InstanceKlass::get_jmethod_id_fetch_or_update(
1777             instanceKlassHandle ik_h, size_t idnum, jmethodID new_id,
1778             jmethodID* new_jmeths, jmethodID* to_dealloc_id_p,
1779             jmethodID** to_dealloc_jmeths_p) {
1780   assert(new_id != NULL, "sanity check");
1781   assert(to_dealloc_id_p != NULL, "sanity check");
1782   assert(to_dealloc_jmeths_p != NULL, "sanity check");
1783   assert(Threads::number_of_threads() == 0 ||
1784          SafepointSynchronize::is_at_safepoint() ||
1785          JmethodIdCreation_lock->owned_by_self(), "sanity check");
1786 
1787   // reacquire the cache - we are locked, single threaded or at a safepoint
1788   jmethodID* jmeths = ik_h->methods_jmethod_ids_acquire();
1789   jmethodID  id     = NULL;
1790   size_t     length = 0;
1791 
1792   if (jmeths == NULL ||                         // no cache yet
1793       (length = (size_t)jmeths[0]) <= idnum) {  // cache is too short
1794     if (jmeths != NULL) {
1795       // copy any existing entries from the old cache
1796       for (size_t index = 0; index < length; index++) {
1797         new_jmeths[index+1] = jmeths[index+1];
1798       }
1799       *to_dealloc_jmeths_p = jmeths;  // save old cache for later delete
1800     }
1801     ik_h->release_set_methods_jmethod_ids(jmeths = new_jmeths);
1802   } else {
1803     // fetch jmethodID (if any) from the existing cache
1804     id = jmeths[idnum+1];
1805     *to_dealloc_jmeths_p = new_jmeths;  // save new cache for later delete
1806   }
1807   if (id == NULL) {
1808     // No matching jmethodID in the existing cache or we have a new
1809     // cache or we just grew the cache. This cache write is done here
1810     // by the first thread to win the foot race because a jmethodID
1811     // needs to be unique once it is generally available.
1812     id = new_id;
1813 
1814     // The jmethodID cache can be read while unlocked so we have to
1815     // make sure the new jmethodID is complete before installing it
1816     // in the cache.
1817     OrderAccess::release_store_ptr(&jmeths[idnum+1], id);
1818   } else {
1819     *to_dealloc_id_p = new_id; // save new id for later delete
1820   }
1821   return id;
1822 }
1823 
1824 
1825 // Common code to get the jmethodID cache length and the jmethodID
1826 // value at index idnum if there is one.
1827 //
1828 void InstanceKlass::get_jmethod_id_length_value(jmethodID* cache,
1829        size_t idnum, size_t *length_p, jmethodID* id_p) {
1830   assert(cache != NULL, "sanity check");
1831   assert(length_p != NULL, "sanity check");
1832   assert(id_p != NULL, "sanity check");
1833 
1834   // cache size is stored in element[0], other elements offset by one
1835   *length_p = (size_t)cache[0];
1836   if (*length_p <= idnum) {  // cache is too short
1837     *id_p = NULL;
1838   } else {
1839     *id_p = cache[idnum+1];  // fetch jmethodID (if any)
1840   }
1841 }
1842 
1843 
1844 // Lookup a jmethodID, NULL if not found.  Do no blocking, no allocations, no handles
1845 jmethodID InstanceKlass::jmethod_id_or_null(Method* method) {
1846   size_t idnum = (size_t)method->method_idnum();
1847   jmethodID* jmeths = methods_jmethod_ids_acquire();
1848   size_t length;                                // length assigned as debugging crumb
1849   jmethodID id = NULL;
1850   if (jmeths != NULL &&                         // If there is a cache
1851       (length = (size_t)jmeths[0]) > idnum) {   // and if it is long enough,
1852     id = jmeths[idnum+1];                       // Look up the id (may be NULL)
1853   }
1854   return id;
1855 }
1856 
1857 int nmethodBucket::decrement() {
1858   return Atomic::add(-1, (volatile int *)&_count);
1859 }
1860 
1861 //
1862 // Walk the list of dependent nmethods searching for nmethods which
1863 // are dependent on the changes that were passed in and mark them for
1864 // deoptimization.  Returns the number of nmethods found.
1865 //
1866 int nmethodBucket::mark_dependent_nmethods(nmethodBucket* deps, DepChange& changes) {
1867   assert_locked_or_safepoint(CodeCache_lock);
1868   int found = 0;
1869   for (nmethodBucket* b = deps; b != NULL; b = b->next()) {
1870     nmethod* nm = b->get_nmethod();
1871     // since dependencies aren't removed until an nmethod becomes a zombie,
1872     // the dependency list may contain nmethods which aren't alive.
1873     if (b->count() > 0 && nm->is_alive() && !nm->is_marked_for_deoptimization() && nm->check_dependency_on(changes)) {
1874       if (TraceDependencies) {
1875         ResourceMark rm;
1876         tty->print_cr("Marked for deoptimization");
1877         changes.print();
1878         nm->print();
1879         nm->print_dependencies();
1880       }
1881       nm->mark_for_deoptimization();
1882       found++;
1883     }
1884   }
1885   return found;
1886 }
1887 
1888 //
1889 // Add an nmethodBucket to the list of dependencies for this nmethod.
1890 // It's possible that an nmethod has multiple dependencies on this klass
1891 // so a count is kept for each bucket to guarantee that creation and
1892 // deletion of dependencies is consistent. Returns new head of the list.
1893 //
1894 nmethodBucket* nmethodBucket::add_dependent_nmethod(nmethodBucket* deps, nmethod* nm) {
1895   assert_locked_or_safepoint(CodeCache_lock);
1896   for (nmethodBucket* b = deps; b != NULL; b = b->next()) {
1897     if (nm == b->get_nmethod()) {
1898       b->increment();
1899       return deps;
1900     }
1901   }
1902   return new nmethodBucket(nm, deps);
1903 }
1904 
1905 //
1906 // Decrement count of the nmethod in the dependency list and remove
1907 // the bucket completely when the count goes to 0.  This method must
1908 // find a corresponding bucket otherwise there's a bug in the
1909 // recording of dependencies. Returns true if the bucket was deleted,
1910 // or marked ready for reclaimation.
1911 bool nmethodBucket::remove_dependent_nmethod(nmethodBucket** deps, nmethod* nm, bool delete_immediately) {
1912   assert_locked_or_safepoint(CodeCache_lock);
1913 
1914   nmethodBucket* first = *deps;
1915   nmethodBucket* last = NULL;
1916 
1917   for (nmethodBucket* b = first; b != NULL; b = b->next()) {
1918     if (nm == b->get_nmethod()) {
1919       int val = b->decrement();
1920       guarantee(val >= 0, "Underflow: %d", val);
1921       if (val == 0) {
1922         if (delete_immediately) {
1923           if (last == NULL) {
1924             *deps = b->next();
1925           } else {
1926             last->set_next(b->next());
1927           }
1928           delete b;
1929         }
1930       }
1931       return true;
1932     }
1933     last = b;
1934   }
1935 
1936 #ifdef ASSERT
1937   tty->print_raw_cr("### can't find dependent nmethod");
1938   nm->print();
1939 #endif // ASSERT
1940   ShouldNotReachHere();
1941   return false;
1942 }
1943 
1944 // Convenience overload, for callers that don't want to delete the nmethodBucket entry.
1945 bool nmethodBucket::remove_dependent_nmethod(nmethodBucket* deps, nmethod* nm) {
1946   nmethodBucket** deps_addr = &deps;
1947   return remove_dependent_nmethod(deps_addr, nm, false /* Don't delete */);
1948 }
1949 
1950 //
1951 // Reclaim all unused buckets. Returns new head of the list.
1952 //
1953 nmethodBucket* nmethodBucket::clean_dependent_nmethods(nmethodBucket* deps) {
1954   nmethodBucket* first = deps;
1955   nmethodBucket* last = NULL;
1956   nmethodBucket* b = first;
1957 
1958   while (b != NULL) {
1959     assert(b->count() >= 0, "bucket count: %d", b->count());
1960     nmethodBucket* next = b->next();
1961     if (b->count() == 0) {
1962       if (last == NULL) {
1963         first = next;
1964       } else {
1965         last->set_next(next);
1966       }
1967       delete b;
1968       // last stays the same.
1969     } else {
1970       last = b;
1971     }
1972     b = next;
1973   }
1974   return first;
1975 }
1976 
1977 #ifndef PRODUCT
1978 void nmethodBucket::print_dependent_nmethods(nmethodBucket* deps, bool verbose) {
1979   int idx = 0;
1980   for (nmethodBucket* b = deps; b != NULL; b = b->next()) {
1981     nmethod* nm = b->get_nmethod();
1982     tty->print("[%d] count=%d { ", idx++, b->count());
1983     if (!verbose) {
1984       nm->print_on(tty, "nmethod");
1985       tty->print_cr(" } ");
1986     } else {
1987       nm->print();
1988       nm->print_dependencies();
1989       tty->print_cr("--- } ");
1990     }
1991   }
1992 }
1993 
1994 bool nmethodBucket::is_dependent_nmethod(nmethodBucket* deps, nmethod* nm) {
1995   for (nmethodBucket* b = deps; b != NULL; b = b->next()) {
1996     if (nm == b->get_nmethod()) {
1997 #ifdef ASSERT
1998       int count = b->count();
1999       assert(count >= 0, "count shouldn't be negative: %d", count);
2000 #endif
2001       return true;
2002     }
2003   }
2004   return false;
2005 }
2006 #endif //PRODUCT
2007 
2008 int InstanceKlass::mark_dependent_nmethods(DepChange& changes) {
2009   assert_locked_or_safepoint(CodeCache_lock);
2010   return nmethodBucket::mark_dependent_nmethods(_dependencies, changes);
2011 }
2012 
2013 void InstanceKlass::clean_dependent_nmethods() {
2014   assert_locked_or_safepoint(CodeCache_lock);
2015 
2016   if (has_unloaded_dependent()) {
2017     _dependencies = nmethodBucket::clean_dependent_nmethods(_dependencies);
2018     set_has_unloaded_dependent(false);
2019   }
2020 #ifdef ASSERT
2021   else {
2022     // Verification
2023     for (nmethodBucket* b = _dependencies; b != NULL; b = b->next()) {
2024       assert(b->count() >= 0, "bucket count: %d", b->count());
2025       assert(b->count() != 0, "empty buckets need to be cleaned");
2026     }
2027   }
2028 #endif
2029 }
2030 
2031 void InstanceKlass::add_dependent_nmethod(nmethod* nm) {
2032   assert_locked_or_safepoint(CodeCache_lock);
2033   _dependencies = nmethodBucket::add_dependent_nmethod(_dependencies, nm);
2034 }
2035 
2036 void InstanceKlass::remove_dependent_nmethod(nmethod* nm, bool delete_immediately) {
2037   assert_locked_or_safepoint(CodeCache_lock);
2038 
2039   if (nmethodBucket::remove_dependent_nmethod(&_dependencies, nm, delete_immediately)) {
2040     set_has_unloaded_dependent(true);
2041   }
2042 }
2043 
2044 #ifndef PRODUCT
2045 void InstanceKlass::print_dependent_nmethods(bool verbose) {
2046   nmethodBucket::print_dependent_nmethods(_dependencies, verbose);
2047 }
2048 
2049 bool InstanceKlass::is_dependent_nmethod(nmethod* nm) {
2050   return nmethodBucket::is_dependent_nmethod(_dependencies, nm);
2051 }
2052 #endif //PRODUCT
2053 
2054 void InstanceKlass::clean_weak_instanceklass_links(BoolObjectClosure* is_alive) {
2055   clean_implementors_list(is_alive);
2056   clean_method_data(is_alive);
2057 
2058   clean_dependent_nmethods();
2059 }
2060 
2061 void InstanceKlass::clean_implementors_list(BoolObjectClosure* is_alive) {
2062   assert(class_loader_data()->is_alive(is_alive), "this klass should be live");
2063   if (is_interface()) {
2064     if (ClassUnloading) {
2065       Klass* impl = implementor();
2066       if (impl != NULL) {
2067         if (!impl->is_loader_alive(is_alive)) {
2068           // remove this guy
2069           Klass** klass = adr_implementor();
2070           assert(klass != NULL, "null klass");
2071           if (klass != NULL) {
2072             *klass = NULL;
2073           }
2074         }
2075       }
2076     }
2077   }
2078 }
2079 
2080 void InstanceKlass::clean_method_data(BoolObjectClosure* is_alive) {
2081   for (int m = 0; m < methods()->length(); m++) {
2082     MethodData* mdo = methods()->at(m)->method_data();
2083     if (mdo != NULL) {
2084       mdo->clean_method_data(is_alive);
2085     }
2086   }
2087 }
2088 
2089 
2090 static void remove_unshareable_in_class(Klass* k) {
2091   // remove klass's unshareable info
2092   k->remove_unshareable_info();
2093 }
2094 
2095 void InstanceKlass::remove_unshareable_info() {
2096   Klass::remove_unshareable_info();
2097   // Unlink the class
2098   if (is_linked()) {
2099     unlink_class();
2100   }
2101   init_implementor();
2102 
2103   constants()->remove_unshareable_info();
2104 
2105   for (int i = 0; i < methods()->length(); i++) {
2106     Method* m = methods()->at(i);
2107     m->remove_unshareable_info();
2108   }
2109 
2110   // do array classes also.
2111   array_klasses_do(remove_unshareable_in_class);
2112 }
2113 
2114 static void restore_unshareable_in_class(Klass* k, TRAPS) {
2115   // Array classes have null protection domain.
2116   // --> see ArrayKlass::complete_create_array_klass()
2117   k->restore_unshareable_info(ClassLoaderData::the_null_class_loader_data(), Handle(), CHECK);
2118 }
2119 
2120 void InstanceKlass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain, TRAPS) {
2121   Klass::restore_unshareable_info(loader_data, protection_domain, CHECK);
2122   instanceKlassHandle ik(THREAD, this);
2123 
2124   Array<Method*>* methods = ik->methods();
2125   int num_methods = methods->length();
2126   for (int index2 = 0; index2 < num_methods; ++index2) {
2127     methodHandle m(THREAD, methods->at(index2));
2128     m->restore_unshareable_info(CHECK);
2129   }
2130   if (JvmtiExport::has_redefined_a_class()) {
2131     // Reinitialize vtable because RedefineClasses may have changed some
2132     // entries in this vtable for super classes so the CDS vtable might
2133     // point to old or obsolete entries.  RedefineClasses doesn't fix up
2134     // vtables in the shared system dictionary, only the main one.
2135     // It also redefines the itable too so fix that too.
2136     ResourceMark rm(THREAD);
2137     ik->vtable()->initialize_vtable(false, CHECK);
2138     ik->itable()->initialize_itable(false, CHECK);
2139   }
2140 
2141   // restore constant pool resolved references
2142   ik->constants()->restore_unshareable_info(CHECK);
2143 
2144   ik->array_klasses_do(restore_unshareable_in_class, CHECK);
2145 }
2146 
2147 // returns true IFF is_in_error_state() has been changed as a result of this call.
2148 bool InstanceKlass::check_sharing_error_state() {
2149   assert(DumpSharedSpaces, "should only be called during dumping");
2150   bool old_state = is_in_error_state();
2151 
2152   if (!is_in_error_state()) {
2153     bool bad = false;
2154     for (InstanceKlass* sup = java_super(); sup; sup = sup->java_super()) {
2155       if (sup->is_in_error_state()) {
2156         bad = true;
2157         break;
2158       }
2159     }
2160     if (!bad) {
2161       Array<Klass*>* interfaces = transitive_interfaces();
2162       for (int i = 0; i < interfaces->length(); i++) {
2163         Klass* iface = interfaces->at(i);
2164         if (InstanceKlass::cast(iface)->is_in_error_state()) {
2165           bad = true;
2166           break;
2167         }
2168       }
2169     }
2170 
2171     if (bad) {
2172       set_in_error_state();
2173     }
2174   }
2175 
2176   return (old_state != is_in_error_state());
2177 }
2178 
2179 static void clear_all_breakpoints(Method* m) {
2180   m->clear_all_breakpoints();
2181 }
2182 
2183 
2184 void InstanceKlass::notify_unload_class(InstanceKlass* ik) {
2185   // notify the debugger
2186   if (JvmtiExport::should_post_class_unload()) {
2187     JvmtiExport::post_class_unload(ik);
2188   }
2189 
2190   // notify ClassLoadingService of class unload
2191   ClassLoadingService::notify_class_unloaded(ik);
2192 }
2193 
2194 void InstanceKlass::release_C_heap_structures(InstanceKlass* ik) {
2195   // Clean up C heap
2196   ik->release_C_heap_structures();
2197   ik->constants()->release_C_heap_structures();
2198 }
2199 
2200 void InstanceKlass::release_C_heap_structures() {
2201 
2202   // Can't release the constant pool here because the constant pool can be
2203   // deallocated separately from the InstanceKlass for default methods and
2204   // redefine classes.
2205 
2206   // Deallocate oop map cache
2207   if (_oop_map_cache != NULL) {
2208     delete _oop_map_cache;
2209     _oop_map_cache = NULL;
2210   }
2211 
2212   // Deallocate JNI identifiers for jfieldIDs
2213   JNIid::deallocate(jni_ids());
2214   set_jni_ids(NULL);
2215 
2216   jmethodID* jmeths = methods_jmethod_ids_acquire();
2217   if (jmeths != (jmethodID*)NULL) {
2218     release_set_methods_jmethod_ids(NULL);
2219     FreeHeap(jmeths);
2220   }
2221 
2222   // Deallocate MemberNameTable
2223   {
2224     Mutex* lock_or_null = SafepointSynchronize::is_at_safepoint() ? NULL : MemberNameTable_lock;
2225     MutexLockerEx ml(lock_or_null, Mutex::_no_safepoint_check_flag);
2226     MemberNameTable* mnt = member_names();
2227     if (mnt != NULL) {
2228       delete mnt;
2229       set_member_names(NULL);
2230     }
2231   }
2232 
2233   // release dependencies
2234   nmethodBucket* b = _dependencies;
2235   _dependencies = NULL;
2236   while (b != NULL) {
2237     nmethodBucket* next = b->next();
2238     delete b;
2239     b = next;
2240   }
2241 
2242   // Deallocate breakpoint records
2243   if (breakpoints() != 0x0) {
2244     methods_do(clear_all_breakpoints);
2245     assert(breakpoints() == 0x0, "should have cleared breakpoints");
2246   }
2247 
2248   // deallocate the cached class file
2249   if (_cached_class_file != NULL) {
2250     os::free(_cached_class_file);
2251     _cached_class_file = NULL;
2252   }
2253 
2254   // Decrement symbol reference counts associated with the unloaded class.
2255   if (_name != NULL) _name->decrement_refcount();
2256   // unreference array name derived from this class name (arrays of an unloaded
2257   // class can't be referenced anymore).
2258   if (_array_name != NULL)  _array_name->decrement_refcount();
2259   if (_source_debug_extension != NULL) FREE_C_HEAP_ARRAY(char, _source_debug_extension);
2260 
2261   assert(_total_instanceKlass_count >= 1, "Sanity check");
2262   Atomic::dec(&_total_instanceKlass_count);
2263 }
2264 
2265 void InstanceKlass::set_source_debug_extension(char* array, int length) {
2266   if (array == NULL) {
2267     _source_debug_extension = NULL;
2268   } else {
2269     // Adding one to the attribute length in order to store a null terminator
2270     // character could cause an overflow because the attribute length is
2271     // already coded with an u4 in the classfile, but in practice, it's
2272     // unlikely to happen.
2273     assert((length+1) > length, "Overflow checking");
2274     char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass);
2275     for (int i = 0; i < length; i++) {
2276       sde[i] = array[i];
2277     }
2278     sde[length] = '\0';
2279     _source_debug_extension = sde;
2280   }
2281 }
2282 
2283 address InstanceKlass::static_field_addr(int offset) {
2284   return (address)(offset + InstanceMirrorKlass::offset_of_static_fields() + cast_from_oop<intptr_t>(java_mirror()));
2285 }
2286 
2287 
2288 const char* InstanceKlass::signature_name() const {
2289   int hash_len = 0;
2290   char hash_buf[40];
2291 
2292   // If this is an anonymous class, append a hash to make the name unique
2293   if (is_anonymous()) {
2294     intptr_t hash = (java_mirror() != NULL) ? java_mirror()->identity_hash() : 0;
2295     jio_snprintf(hash_buf, sizeof(hash_buf), "/" UINTX_FORMAT, (uintx)hash);
2296     hash_len = (int)strlen(hash_buf);
2297   }
2298 
2299   // Get the internal name as a c string
2300   const char* src = (const char*) (name()->as_C_string());
2301   const int src_length = (int)strlen(src);
2302 
2303   char* dest = NEW_RESOURCE_ARRAY(char, src_length + hash_len + 3);
2304 
2305   // Add L as type indicator
2306   int dest_index = 0;
2307   dest[dest_index++] = 'L';
2308 
2309   // Add the actual class name
2310   for (int src_index = 0; src_index < src_length; ) {
2311     dest[dest_index++] = src[src_index++];
2312   }
2313 
2314   // If we have a hash, append it
2315   for (int hash_index = 0; hash_index < hash_len; ) {
2316     dest[dest_index++] = hash_buf[hash_index++];
2317   }
2318 
2319   // Add the semicolon and the NULL
2320   dest[dest_index++] = ';';
2321   dest[dest_index] = '\0';
2322   return dest;
2323 }
2324 
2325 // different verisons of is_same_class_package
2326 bool InstanceKlass::is_same_class_package(Klass* class2) {
2327   if (class2->is_objArray_klass()) {
2328     class2 = ObjArrayKlass::cast(class2)->bottom_klass();
2329   }
2330   oop classloader2 = class2->class_loader();
2331   Symbol* classname2 = class2->name();
2332 
2333   return InstanceKlass::is_same_class_package(class_loader(), name(),
2334                                               classloader2, classname2);
2335 }
2336 
2337 bool InstanceKlass::is_same_class_package(oop classloader2, Symbol* classname2) {
2338   return InstanceKlass::is_same_class_package(class_loader(), name(),
2339                                               classloader2, classname2);
2340 }
2341 
2342 // return true if two classes are in the same package, classloader
2343 // and classname information is enough to determine a class's package
2344 bool InstanceKlass::is_same_class_package(oop class_loader1, Symbol* class_name1,
2345                                           oop class_loader2, Symbol* class_name2) {
2346   if (class_loader1 != class_loader2) {
2347     return false;
2348   } else if (class_name1 == class_name2) {
2349     return true;                // skip painful bytewise comparison
2350   } else {
2351     ResourceMark rm;
2352 
2353     // The Symbol*'s are in UTF8 encoding. Since we only need to check explicitly
2354     // for ASCII characters ('/', 'L', '['), we can keep them in UTF8 encoding.
2355     // Otherwise, we just compare jbyte values between the strings.
2356     const jbyte *name1 = class_name1->base();
2357     const jbyte *name2 = class_name2->base();
2358 
2359     const jbyte *last_slash1 = UTF8::strrchr(name1, class_name1->utf8_length(), '/');
2360     const jbyte *last_slash2 = UTF8::strrchr(name2, class_name2->utf8_length(), '/');
2361 
2362     if ((last_slash1 == NULL) || (last_slash2 == NULL)) {
2363       // One of the two doesn't have a package.  Only return true
2364       // if the other one also doesn't have a package.
2365       return last_slash1 == last_slash2;
2366     } else {
2367       // Skip over '['s
2368       if (*name1 == '[') {
2369         do {
2370           name1++;
2371         } while (*name1 == '[');
2372         if (*name1 != 'L') {
2373           // Something is terribly wrong.  Shouldn't be here.
2374           return false;
2375         }
2376       }
2377       if (*name2 == '[') {
2378         do {
2379           name2++;
2380         } while (*name2 == '[');
2381         if (*name2 != 'L') {
2382           // Something is terribly wrong.  Shouldn't be here.
2383           return false;
2384         }
2385       }
2386 
2387       // Check that package part is identical
2388       int length1 = last_slash1 - name1;
2389       int length2 = last_slash2 - name2;
2390 
2391       return UTF8::equal(name1, length1, name2, length2);
2392     }
2393   }
2394 }
2395 
2396 // Returns true iff super_method can be overridden by a method in targetclassname
2397 // See JSL 3rd edition 8.4.6.1
2398 // Assumes name-signature match
2399 // "this" is InstanceKlass of super_method which must exist
2400 // note that the InstanceKlass of the method in the targetclassname has not always been created yet
2401 bool InstanceKlass::is_override(const methodHandle& super_method, Handle targetclassloader, Symbol* targetclassname, TRAPS) {
2402    // Private methods can not be overridden
2403    if (super_method->is_private()) {
2404      return false;
2405    }
2406    // If super method is accessible, then override
2407    if ((super_method->is_protected()) ||
2408        (super_method->is_public())) {
2409      return true;
2410    }
2411    // Package-private methods are not inherited outside of package
2412    assert(super_method->is_package_private(), "must be package private");
2413    return(is_same_class_package(targetclassloader(), targetclassname));
2414 }
2415 
2416 /* defined for now in jvm.cpp, for historical reasons *--
2417 Klass* InstanceKlass::compute_enclosing_class_impl(instanceKlassHandle self,
2418                                                      Symbol*& simple_name_result, TRAPS) {
2419   ...
2420 }
2421 */
2422 
2423 // tell if two classes have the same enclosing class (at package level)
2424 bool InstanceKlass::is_same_package_member_impl(instanceKlassHandle class1,
2425                                                 Klass* class2_oop, TRAPS) {
2426   if (class2_oop == class1())                       return true;
2427   if (!class2_oop->is_instance_klass())  return false;
2428   instanceKlassHandle class2(THREAD, class2_oop);
2429 
2430   // must be in same package before we try anything else
2431   if (!class1->is_same_class_package(class2->class_loader(), class2->name()))
2432     return false;
2433 
2434   // As long as there is an outer1.getEnclosingClass,
2435   // shift the search outward.
2436   instanceKlassHandle outer1 = class1;
2437   for (;;) {
2438     // As we walk along, look for equalities between outer1 and class2.
2439     // Eventually, the walks will terminate as outer1 stops
2440     // at the top-level class around the original class.
2441     bool ignore_inner_is_member;
2442     Klass* next = outer1->compute_enclosing_class(&ignore_inner_is_member,
2443                                                     CHECK_false);
2444     if (next == NULL)  break;
2445     if (next == class2())  return true;
2446     outer1 = instanceKlassHandle(THREAD, next);
2447   }
2448 
2449   // Now do the same for class2.
2450   instanceKlassHandle outer2 = class2;
2451   for (;;) {
2452     bool ignore_inner_is_member;
2453     Klass* next = outer2->compute_enclosing_class(&ignore_inner_is_member,
2454                                                     CHECK_false);
2455     if (next == NULL)  break;
2456     // Might as well check the new outer against all available values.
2457     if (next == class1())  return true;
2458     if (next == outer1())  return true;
2459     outer2 = instanceKlassHandle(THREAD, next);
2460   }
2461 
2462   // If by this point we have not found an equality between the
2463   // two classes, we know they are in separate package members.
2464   return false;
2465 }
2466 
2467 bool InstanceKlass::find_inner_classes_attr(instanceKlassHandle k, int* ooff, int* noff, TRAPS) {
2468   constantPoolHandle i_cp(THREAD, k->constants());
2469   for (InnerClassesIterator iter(k); !iter.done(); iter.next()) {
2470     int ioff = iter.inner_class_info_index();
2471     if (ioff != 0) {
2472       // Check to see if the name matches the class we're looking for
2473       // before attempting to find the class.
2474       if (i_cp->klass_name_at_matches(k, ioff)) {
2475         Klass* inner_klass = i_cp->klass_at(ioff, CHECK_false);
2476         if (k() == inner_klass) {
2477           *ooff = iter.outer_class_info_index();
2478           *noff = iter.inner_name_index();
2479           return true;
2480         }
2481       }
2482     }
2483   }
2484   return false;
2485 }
2486 
2487 Klass* InstanceKlass::compute_enclosing_class_impl(instanceKlassHandle k, bool* inner_is_member, TRAPS) {
2488   instanceKlassHandle outer_klass;
2489   *inner_is_member = false;
2490   int ooff = 0, noff = 0;
2491   if (find_inner_classes_attr(k, &ooff, &noff, THREAD)) {
2492     constantPoolHandle i_cp(THREAD, k->constants());
2493     if (ooff != 0) {
2494       Klass* ok = i_cp->klass_at(ooff, CHECK_NULL);
2495       outer_klass = instanceKlassHandle(THREAD, ok);
2496       *inner_is_member = true;
2497     }
2498     if (outer_klass.is_null()) {
2499       // It may be anonymous; try for that.
2500       int encl_method_class_idx = k->enclosing_method_class_index();
2501       if (encl_method_class_idx != 0) {
2502         Klass* ok = i_cp->klass_at(encl_method_class_idx, CHECK_NULL);
2503         outer_klass = instanceKlassHandle(THREAD, ok);
2504         *inner_is_member = false;
2505       }
2506     }
2507   }
2508 
2509   // If no inner class attribute found for this class.
2510   if (outer_klass.is_null())  return NULL;
2511 
2512   // Throws an exception if outer klass has not declared k as an inner klass
2513   // We need evidence that each klass knows about the other, or else
2514   // the system could allow a spoof of an inner class to gain access rights.
2515   Reflection::check_for_inner_class(outer_klass, k, *inner_is_member, CHECK_NULL);
2516   return outer_klass();
2517 }
2518 
2519 jint InstanceKlass::compute_modifier_flags(TRAPS) const {
2520   jint access = access_flags().as_int();
2521 
2522   // But check if it happens to be member class.
2523   instanceKlassHandle ik(THREAD, this);
2524   InnerClassesIterator iter(ik);
2525   for (; !iter.done(); iter.next()) {
2526     int ioff = iter.inner_class_info_index();
2527     // Inner class attribute can be zero, skip it.
2528     // Strange but true:  JVM spec. allows null inner class refs.
2529     if (ioff == 0) continue;
2530 
2531     // only look at classes that are already loaded
2532     // since we are looking for the flags for our self.
2533     Symbol* inner_name = ik->constants()->klass_name_at(ioff);
2534     if ((ik->name() == inner_name)) {
2535       // This is really a member class.
2536       access = iter.inner_access_flags();
2537       break;
2538     }
2539   }
2540   // Remember to strip ACC_SUPER bit
2541   return (access & (~JVM_ACC_SUPER)) & JVM_ACC_WRITTEN_FLAGS;
2542 }
2543 
2544 jint InstanceKlass::jvmti_class_status() const {
2545   jint result = 0;
2546 
2547   if (is_linked()) {
2548     result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED;
2549   }
2550 
2551   if (is_initialized()) {
2552     assert(is_linked(), "Class status is not consistent");
2553     result |= JVMTI_CLASS_STATUS_INITIALIZED;
2554   }
2555   if (is_in_error_state()) {
2556     result |= JVMTI_CLASS_STATUS_ERROR;
2557   }
2558   return result;
2559 }
2560 
2561 Method* InstanceKlass::method_at_itable(Klass* holder, int index, TRAPS) {
2562   itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2563   int method_table_offset_in_words = ioe->offset()/wordSize;
2564   int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words())
2565                        / itableOffsetEntry::size();
2566 
2567   for (int cnt = 0 ; ; cnt ++, ioe ++) {
2568     // If the interface isn't implemented by the receiver class,
2569     // the VM should throw IncompatibleClassChangeError.
2570     if (cnt >= nof_interfaces) {
2571       THROW_NULL(vmSymbols::java_lang_IncompatibleClassChangeError());
2572     }
2573 
2574     Klass* ik = ioe->interface_klass();
2575     if (ik == holder) break;
2576   }
2577 
2578   itableMethodEntry* ime = ioe->first_method_entry(this);
2579   Method* m = ime[index].method();
2580   if (m == NULL) {
2581     THROW_NULL(vmSymbols::java_lang_AbstractMethodError());
2582   }
2583   return m;
2584 }
2585 
2586 
2587 #if INCLUDE_JVMTI
2588 // update default_methods for redefineclasses for methods that are
2589 // not yet in the vtable due to concurrent subclass define and superinterface
2590 // redefinition
2591 // Note: those in the vtable, should have been updated via adjust_method_entries
2592 void InstanceKlass::adjust_default_methods(InstanceKlass* holder, bool* trace_name_printed) {
2593   // search the default_methods for uses of either obsolete or EMCP methods
2594   if (default_methods() != NULL) {
2595     for (int index = 0; index < default_methods()->length(); index ++) {
2596       Method* old_method = default_methods()->at(index);
2597       if (old_method == NULL || old_method->method_holder() != holder || !old_method->is_old()) {
2598         continue; // skip uninteresting entries
2599       }
2600       assert(!old_method->is_deleted(), "default methods may not be deleted");
2601 
2602       Method* new_method = holder->method_with_idnum(old_method->orig_method_idnum());
2603 
2604       assert(new_method != NULL, "method_with_idnum() should not be NULL");
2605       assert(old_method != new_method, "sanity check");
2606 
2607       default_methods()->at_put(index, new_method);
2608       if (RC_TRACE_IN_RANGE(0x00100000, 0x00400000)) {
2609         if (!(*trace_name_printed)) {
2610           // RC_TRACE_MESG macro has an embedded ResourceMark
2611           RC_TRACE_MESG(("adjust: klassname=%s default methods from name=%s",
2612                          external_name(),
2613                          old_method->method_holder()->external_name()));
2614           *trace_name_printed = true;
2615         }
2616         RC_TRACE(0x00100000, ("default method update: %s(%s) ",
2617                               new_method->name()->as_C_string(),
2618                               new_method->signature()->as_C_string()));
2619       }
2620     }
2621   }
2622 }
2623 #endif // INCLUDE_JVMTI
2624 
2625 // On-stack replacement stuff
2626 void InstanceKlass::add_osr_nmethod(nmethod* n) {
2627   // only one compilation can be active
2628   {
2629     // This is a short non-blocking critical region, so the no safepoint check is ok.
2630     MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2631     assert(n->is_osr_method(), "wrong kind of nmethod");
2632     n->set_osr_link(osr_nmethods_head());
2633     set_osr_nmethods_head(n);
2634     // Raise the highest osr level if necessary
2635     if (TieredCompilation) {
2636       Method* m = n->method();
2637       m->set_highest_osr_comp_level(MAX2(m->highest_osr_comp_level(), n->comp_level()));
2638     }
2639   }
2640 
2641   // Get rid of the osr methods for the same bci that have lower levels.
2642   if (TieredCompilation) {
2643     for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) {
2644       nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true);
2645       if (inv != NULL && inv->is_in_use()) {
2646         inv->make_not_entrant();
2647       }
2648     }
2649   }
2650 }
2651 
2652 
2653 void InstanceKlass::remove_osr_nmethod(nmethod* n) {
2654   // This is a short non-blocking critical region, so the no safepoint check is ok.
2655   MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2656   assert(n->is_osr_method(), "wrong kind of nmethod");
2657   nmethod* last = NULL;
2658   nmethod* cur  = osr_nmethods_head();
2659   int max_level = CompLevel_none;  // Find the max comp level excluding n
2660   Method* m = n->method();
2661   // Search for match
2662   while(cur != NULL && cur != n) {
2663     if (TieredCompilation && m == cur->method()) {
2664       // Find max level before n
2665       max_level = MAX2(max_level, cur->comp_level());
2666     }
2667     last = cur;
2668     cur = cur->osr_link();
2669   }
2670   nmethod* next = NULL;
2671   if (cur == n) {
2672     next = cur->osr_link();
2673     if (last == NULL) {
2674       // Remove first element
2675       set_osr_nmethods_head(next);
2676     } else {
2677       last->set_osr_link(next);
2678     }
2679   }
2680   n->set_osr_link(NULL);
2681   if (TieredCompilation) {
2682     cur = next;
2683     while (cur != NULL) {
2684       // Find max level after n
2685       if (m == cur->method()) {
2686         max_level = MAX2(max_level, cur->comp_level());
2687       }
2688       cur = cur->osr_link();
2689     }
2690     m->set_highest_osr_comp_level(max_level);
2691   }
2692 }
2693 
2694 int InstanceKlass::mark_osr_nmethods(const Method* m) {
2695   // This is a short non-blocking critical region, so the no safepoint check is ok.
2696   MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2697   nmethod* osr = osr_nmethods_head();
2698   int found = 0;
2699   while (osr != NULL) {
2700     assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
2701     if (osr->method() == m) {
2702       osr->mark_for_deoptimization();
2703       found++;
2704     }
2705     osr = osr->osr_link();
2706   }
2707   return found;
2708 }
2709 
2710 nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const {
2711   // This is a short non-blocking critical region, so the no safepoint check is ok.
2712   MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2713   nmethod* osr = osr_nmethods_head();
2714   nmethod* best = NULL;
2715   while (osr != NULL) {
2716     assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
2717     // There can be a time when a c1 osr method exists but we are waiting
2718     // for a c2 version. When c2 completes its osr nmethod we will trash
2719     // the c1 version and only be able to find the c2 version. However
2720     // while we overflow in the c1 code at back branches we don't want to
2721     // try and switch to the same code as we are already running
2722 
2723     if (osr->method() == m &&
2724         (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) {
2725       if (match_level) {
2726         if (osr->comp_level() == comp_level) {
2727           // Found a match - return it.
2728           return osr;
2729         }
2730       } else {
2731         if (best == NULL || (osr->comp_level() > best->comp_level())) {
2732           if (osr->comp_level() == CompLevel_highest_tier) {
2733             // Found the best possible - return it.
2734             return osr;
2735           }
2736           best = osr;
2737         }
2738       }
2739     }
2740     osr = osr->osr_link();
2741   }
2742   if (best != NULL && best->comp_level() >= comp_level && match_level == false) {
2743     return best;
2744   }
2745   return NULL;
2746 }
2747 
2748 bool InstanceKlass::add_member_name(Handle mem_name) {
2749   jweak mem_name_wref = JNIHandles::make_weak_global(mem_name);
2750   MutexLocker ml(MemberNameTable_lock);
2751   DEBUG_ONLY(No_Safepoint_Verifier nsv);
2752 
2753   // Check if method has been redefined while taking out MemberNameTable_lock, if so
2754   // return false.  We cannot cache obsolete methods. They will crash when the function
2755   // is called!
2756   Method* method = (Method*)java_lang_invoke_MemberName::vmtarget(mem_name());
2757   if (method->is_obsolete()) {
2758     return false;
2759   } else if (method->is_old()) {
2760     // Replace method with redefined version
2761     java_lang_invoke_MemberName::set_vmtarget(mem_name(), method_with_idnum(method->method_idnum()));
2762   }
2763 
2764   if (_member_names == NULL) {
2765     _member_names = new (ResourceObj::C_HEAP, mtClass) MemberNameTable(idnum_allocated_count());
2766   }
2767   _member_names->add_member_name(mem_name_wref);
2768   return true;
2769 }
2770 
2771 // -----------------------------------------------------------------------------------------------------
2772 // Printing
2773 
2774 #ifndef PRODUCT
2775 
2776 #define BULLET  " - "
2777 
2778 static const char* state_names[] = {
2779   "allocated", "loaded", "linked", "being_initialized", "fully_initialized", "initialization_error"
2780 };
2781 
2782 static void print_vtable(intptr_t* start, int len, outputStream* st) {
2783   for (int i = 0; i < len; i++) {
2784     intptr_t e = start[i];
2785     st->print("%d : " INTPTR_FORMAT, i, e);
2786     if (e != 0 && ((Metadata*)e)->is_metaspace_object()) {
2787       st->print(" ");
2788       ((Metadata*)e)->print_value_on(st);
2789     }
2790     st->cr();
2791   }
2792 }
2793 
2794 void InstanceKlass::print_on(outputStream* st) const {
2795   assert(is_klass(), "must be klass");
2796   Klass::print_on(st);
2797 
2798   st->print(BULLET"instance size:     %d", size_helper());                        st->cr();
2799   st->print(BULLET"klass size:        %d", size());                               st->cr();
2800   st->print(BULLET"access:            "); access_flags().print_on(st);            st->cr();
2801   st->print(BULLET"state:             "); st->print_cr("%s", state_names[_init_state]);
2802   st->print(BULLET"name:              "); name()->print_value_on(st);             st->cr();
2803   st->print(BULLET"super:             "); super()->print_value_on_maybe_null(st); st->cr();
2804   st->print(BULLET"sub:               ");
2805   Klass* sub = subklass();
2806   int n;
2807   for (n = 0; sub != NULL; n++, sub = sub->next_sibling()) {
2808     if (n < MaxSubklassPrintSize) {
2809       sub->print_value_on(st);
2810       st->print("   ");
2811     }
2812   }
2813   if (n >= MaxSubklassPrintSize) st->print("(" INTX_FORMAT " more klasses...)", n - MaxSubklassPrintSize);
2814   st->cr();
2815 
2816   if (is_interface()) {
2817     st->print_cr(BULLET"nof implementors:  %d", nof_implementors());
2818     if (nof_implementors() == 1) {
2819       st->print_cr(BULLET"implementor:    ");
2820       st->print("   ");
2821       implementor()->print_value_on(st);
2822       st->cr();
2823     }
2824   }
2825 
2826   st->print(BULLET"arrays:            "); array_klasses()->print_value_on_maybe_null(st); st->cr();
2827   st->print(BULLET"methods:           "); methods()->print_value_on(st);                  st->cr();
2828   if (Verbose || WizardMode) {
2829     Array<Method*>* method_array = methods();
2830     for (int i = 0; i < method_array->length(); i++) {
2831       st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
2832     }
2833   }
2834   st->print(BULLET"method ordering:   "); method_ordering()->print_value_on(st);      st->cr();
2835   st->print(BULLET"default_methods:   "); default_methods()->print_value_on(st);      st->cr();
2836   if (Verbose && default_methods() != NULL) {
2837     Array<Method*>* method_array = default_methods();
2838     for (int i = 0; i < method_array->length(); i++) {
2839       st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
2840     }
2841   }
2842   if (default_vtable_indices() != NULL) {
2843     st->print(BULLET"default vtable indices:   "); default_vtable_indices()->print_value_on(st);       st->cr();
2844   }
2845   st->print(BULLET"local interfaces:  "); local_interfaces()->print_value_on(st);      st->cr();
2846   st->print(BULLET"trans. interfaces: "); transitive_interfaces()->print_value_on(st); st->cr();
2847   st->print(BULLET"constants:         "); constants()->print_value_on(st);         st->cr();
2848   if (class_loader_data() != NULL) {
2849     st->print(BULLET"class loader data:  ");
2850     class_loader_data()->print_value_on(st);
2851     st->cr();
2852   }
2853   st->print(BULLET"host class:        "); host_klass()->print_value_on_maybe_null(st); st->cr();
2854   if (source_file_name() != NULL) {
2855     st->print(BULLET"source file:       ");
2856     source_file_name()->print_value_on(st);
2857     st->cr();
2858   }
2859   if (source_debug_extension() != NULL) {
2860     st->print(BULLET"source debug extension:       ");
2861     st->print("%s", source_debug_extension());
2862     st->cr();
2863   }
2864   st->print(BULLET"class annotations:       "); class_annotations()->print_value_on(st); st->cr();
2865   st->print(BULLET"class type annotations:  "); class_type_annotations()->print_value_on(st); st->cr();
2866   st->print(BULLET"field annotations:       "); fields_annotations()->print_value_on(st); st->cr();
2867   st->print(BULLET"field type annotations:  "); fields_type_annotations()->print_value_on(st); st->cr();
2868   {
2869     bool have_pv = false;
2870     // previous versions are linked together through the InstanceKlass
2871     for (InstanceKlass* pv_node = _previous_versions;
2872          pv_node != NULL;
2873          pv_node = pv_node->previous_versions()) {
2874       if (!have_pv)
2875         st->print(BULLET"previous version:  ");
2876       have_pv = true;
2877       pv_node->constants()->print_value_on(st);
2878     }
2879     if (have_pv) st->cr();
2880   }
2881 
2882   if (generic_signature() != NULL) {
2883     st->print(BULLET"generic signature: ");
2884     generic_signature()->print_value_on(st);
2885     st->cr();
2886   }
2887   st->print(BULLET"inner classes:     "); inner_classes()->print_value_on(st);     st->cr();
2888   st->print(BULLET"java mirror:       "); java_mirror()->print_value_on(st);       st->cr();
2889   st->print(BULLET"vtable length      %d  (start addr: " INTPTR_FORMAT ")", vtable_length(), p2i(start_of_vtable())); st->cr();
2890   if (vtable_length() > 0 && (Verbose || WizardMode))  print_vtable(start_of_vtable(), vtable_length(), st);
2891   st->print(BULLET"itable length      %d (start addr: " INTPTR_FORMAT ")", itable_length(), p2i(start_of_itable())); st->cr();
2892   if (itable_length() > 0 && (Verbose || WizardMode))  print_vtable(start_of_itable(), itable_length(), st);
2893   st->print_cr(BULLET"---- static fields (%d words):", static_field_size());
2894   FieldPrinter print_static_field(st);
2895   ((InstanceKlass*)this)->do_local_static_fields(&print_static_field);
2896   st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size());
2897   FieldPrinter print_nonstatic_field(st);
2898   InstanceKlass* ik = const_cast<InstanceKlass*>(this);
2899   ik->do_nonstatic_fields(&print_nonstatic_field);
2900 
2901   st->print(BULLET"non-static oop maps: ");
2902   OopMapBlock* map     = start_of_nonstatic_oop_maps();
2903   OopMapBlock* end_map = map + nonstatic_oop_map_count();
2904   while (map < end_map) {
2905     st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1));
2906     map++;
2907   }
2908   st->cr();
2909 }
2910 
2911 #endif //PRODUCT
2912 
2913 void InstanceKlass::print_value_on(outputStream* st) const {
2914   assert(is_klass(), "must be klass");
2915   if (Verbose || WizardMode)  access_flags().print_on(st);
2916   name()->print_value_on(st);
2917 }
2918 
2919 #ifndef PRODUCT
2920 
2921 void FieldPrinter::do_field(fieldDescriptor* fd) {
2922   _st->print(BULLET);
2923    if (_obj == NULL) {
2924      fd->print_on(_st);
2925      _st->cr();
2926    } else {
2927      fd->print_on_for(_st, _obj);
2928      _st->cr();
2929    }
2930 }
2931 
2932 
2933 void InstanceKlass::oop_print_on(oop obj, outputStream* st) {
2934   Klass::oop_print_on(obj, st);
2935 
2936   if (this == SystemDictionary::String_klass()) {
2937     typeArrayOop value  = java_lang_String::value(obj);
2938     juint        offset = java_lang_String::offset(obj);
2939     juint        length = java_lang_String::length(obj);
2940     if (value != NULL &&
2941         value->is_typeArray() &&
2942         offset          <= (juint) value->length() &&
2943         offset + length <= (juint) value->length()) {
2944       st->print(BULLET"string: ");
2945       java_lang_String::print(obj, st);
2946       st->cr();
2947       if (!WizardMode)  return;  // that is enough
2948     }
2949   }
2950 
2951   st->print_cr(BULLET"---- fields (total size %d words):", oop_size(obj));
2952   FieldPrinter print_field(st, obj);
2953   do_nonstatic_fields(&print_field);
2954 
2955   if (this == SystemDictionary::Class_klass()) {
2956     st->print(BULLET"signature: ");
2957     java_lang_Class::print_signature(obj, st);
2958     st->cr();
2959     Klass* mirrored_klass = java_lang_Class::as_Klass(obj);
2960     st->print(BULLET"fake entry for mirror: ");
2961     mirrored_klass->print_value_on_maybe_null(st);
2962     st->cr();
2963     Klass* array_klass = java_lang_Class::array_klass(obj);
2964     st->print(BULLET"fake entry for array: ");
2965     array_klass->print_value_on_maybe_null(st);
2966     st->cr();
2967     st->print_cr(BULLET"fake entry for oop_size: %d", java_lang_Class::oop_size(obj));
2968     st->print_cr(BULLET"fake entry for static_oop_field_count: %d", java_lang_Class::static_oop_field_count(obj));
2969     Klass* real_klass = java_lang_Class::as_Klass(obj);
2970     if (real_klass != NULL && real_klass->is_instance_klass()) {
2971       InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field);
2972     }
2973   } else if (this == SystemDictionary::MethodType_klass()) {
2974     st->print(BULLET"signature: ");
2975     java_lang_invoke_MethodType::print_signature(obj, st);
2976     st->cr();
2977   }
2978 }
2979 
2980 #endif //PRODUCT
2981 
2982 void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) {
2983   st->print("a ");
2984   name()->print_value_on(st);
2985   obj->print_address_on(st);
2986   if (this == SystemDictionary::String_klass()
2987       && java_lang_String::value(obj) != NULL) {
2988     ResourceMark rm;
2989     int len = java_lang_String::length(obj);
2990     int plen = (len < 24 ? len : 12);
2991     char* str = java_lang_String::as_utf8_string(obj, 0, plen);
2992     st->print(" = \"%s\"", str);
2993     if (len > plen)
2994       st->print("...[%d]", len);
2995   } else if (this == SystemDictionary::Class_klass()) {
2996     Klass* k = java_lang_Class::as_Klass(obj);
2997     st->print(" = ");
2998     if (k != NULL) {
2999       k->print_value_on(st);
3000     } else {
3001       const char* tname = type2name(java_lang_Class::primitive_type(obj));
3002       st->print("%s", tname ? tname : "type?");
3003     }
3004   } else if (this == SystemDictionary::MethodType_klass()) {
3005     st->print(" = ");
3006     java_lang_invoke_MethodType::print_signature(obj, st);
3007   } else if (java_lang_boxing_object::is_instance(obj)) {
3008     st->print(" = ");
3009     java_lang_boxing_object::print(obj, st);
3010   } else if (this == SystemDictionary::LambdaForm_klass()) {
3011     oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj);
3012     if (vmentry != NULL) {
3013       st->print(" => ");
3014       vmentry->print_value_on(st);
3015     }
3016   } else if (this == SystemDictionary::MemberName_klass()) {
3017     Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj);
3018     if (vmtarget != NULL) {
3019       st->print(" = ");
3020       vmtarget->print_value_on(st);
3021     } else {
3022       java_lang_invoke_MemberName::clazz(obj)->print_value_on(st);
3023       st->print(".");
3024       java_lang_invoke_MemberName::name(obj)->print_value_on(st);
3025     }
3026   }
3027 }
3028 
3029 const char* InstanceKlass::internal_name() const {
3030   return external_name();
3031 }
3032 
3033 #if INCLUDE_SERVICES
3034 // Size Statistics
3035 void InstanceKlass::collect_statistics(KlassSizeStats *sz) const {
3036   Klass::collect_statistics(sz);
3037 
3038   sz->_inst_size  = HeapWordSize * size_helper();
3039   sz->_vtab_bytes = HeapWordSize * align_object_offset(vtable_length());
3040   sz->_itab_bytes = HeapWordSize * align_object_offset(itable_length());
3041   sz->_nonstatic_oopmap_bytes = HeapWordSize *
3042         ((is_interface() || is_anonymous()) ?
3043          align_object_offset(nonstatic_oop_map_size()) :
3044          nonstatic_oop_map_size());
3045 
3046   int n = 0;
3047   n += (sz->_methods_array_bytes         = sz->count_array(methods()));
3048   n += (sz->_method_ordering_bytes       = sz->count_array(method_ordering()));
3049   n += (sz->_local_interfaces_bytes      = sz->count_array(local_interfaces()));
3050   n += (sz->_transitive_interfaces_bytes = sz->count_array(transitive_interfaces()));
3051   n += (sz->_fields_bytes                = sz->count_array(fields()));
3052   n += (sz->_inner_classes_bytes         = sz->count_array(inner_classes()));
3053   sz->_ro_bytes += n;
3054 
3055   const ConstantPool* cp = constants();
3056   if (cp) {
3057     cp->collect_statistics(sz);
3058   }
3059 
3060   const Annotations* anno = annotations();
3061   if (anno) {
3062     anno->collect_statistics(sz);
3063   }
3064 
3065   const Array<Method*>* methods_array = methods();
3066   if (methods()) {
3067     for (int i = 0; i < methods_array->length(); i++) {
3068       Method* method = methods_array->at(i);
3069       if (method) {
3070         sz->_method_count ++;
3071         method->collect_statistics(sz);
3072       }
3073     }
3074   }
3075 }
3076 #endif // INCLUDE_SERVICES
3077 
3078 // Verification
3079 
3080 class VerifyFieldClosure: public OopClosure {
3081  protected:
3082   template <class T> void do_oop_work(T* p) {
3083     oop obj = oopDesc::load_decode_heap_oop(p);
3084     if (!obj->is_oop_or_null()) {
3085       tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p2i(p), p2i(obj));
3086       Universe::print();
3087       guarantee(false, "boom");
3088     }
3089   }
3090  public:
3091   virtual void do_oop(oop* p)       { VerifyFieldClosure::do_oop_work(p); }
3092   virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); }
3093 };
3094 
3095 void InstanceKlass::verify_on(outputStream* st) {
3096 #ifndef PRODUCT
3097   // Avoid redundant verifies, this really should be in product.
3098   if (_verify_count == Universe::verify_count()) return;
3099   _verify_count = Universe::verify_count();
3100 #endif
3101 
3102   // Verify Klass
3103   Klass::verify_on(st);
3104 
3105   // Verify that klass is present in ClassLoaderData
3106   guarantee(class_loader_data()->contains_klass(this),
3107             "this class isn't found in class loader data");
3108 
3109   // Verify vtables
3110   if (is_linked()) {
3111     ResourceMark rm;
3112     // $$$ This used to be done only for m/s collections.  Doing it
3113     // always seemed a valid generalization.  (DLD -- 6/00)
3114     vtable()->verify(st);
3115   }
3116 
3117   // Verify first subklass
3118   if (subklass() != NULL) {
3119     guarantee(subklass()->is_klass(), "should be klass");
3120   }
3121 
3122   // Verify siblings
3123   Klass* super = this->super();
3124   Klass* sib = next_sibling();
3125   if (sib != NULL) {
3126     if (sib == this) {
3127       fatal("subclass points to itself " PTR_FORMAT, p2i(sib));
3128     }
3129 
3130     guarantee(sib->is_klass(), "should be klass");
3131     guarantee(sib->super() == super, "siblings should have same superklass");
3132   }
3133 
3134   // Verify implementor fields
3135   Klass* im = implementor();
3136   if (im != NULL) {
3137     guarantee(is_interface(), "only interfaces should have implementor set");
3138     guarantee(im->is_klass(), "should be klass");
3139     guarantee(!im->is_interface() || im == this,
3140       "implementors cannot be interfaces");
3141   }
3142 
3143   // Verify local interfaces
3144   if (local_interfaces()) {
3145     Array<Klass*>* local_interfaces = this->local_interfaces();
3146     for (int j = 0; j < local_interfaces->length(); j++) {
3147       Klass* e = local_interfaces->at(j);
3148       guarantee(e->is_klass() && e->is_interface(), "invalid local interface");
3149     }
3150   }
3151 
3152   // Verify transitive interfaces
3153   if (transitive_interfaces() != NULL) {
3154     Array<Klass*>* transitive_interfaces = this->transitive_interfaces();
3155     for (int j = 0; j < transitive_interfaces->length(); j++) {
3156       Klass* e = transitive_interfaces->at(j);
3157       guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface");
3158     }
3159   }
3160 
3161   // Verify methods
3162   if (methods() != NULL) {
3163     Array<Method*>* methods = this->methods();
3164     for (int j = 0; j < methods->length(); j++) {
3165       guarantee(methods->at(j)->is_method(), "non-method in methods array");
3166     }
3167     for (int j = 0; j < methods->length() - 1; j++) {
3168       Method* m1 = methods->at(j);
3169       Method* m2 = methods->at(j + 1);
3170       guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3171     }
3172   }
3173 
3174   // Verify method ordering
3175   if (method_ordering() != NULL) {
3176     Array<int>* method_ordering = this->method_ordering();
3177     int length = method_ordering->length();
3178     if (JvmtiExport::can_maintain_original_method_order() ||
3179         ((UseSharedSpaces || DumpSharedSpaces) && length != 0)) {
3180       guarantee(length == methods()->length(), "invalid method ordering length");
3181       jlong sum = 0;
3182       for (int j = 0; j < length; j++) {
3183         int original_index = method_ordering->at(j);
3184         guarantee(original_index >= 0, "invalid method ordering index");
3185         guarantee(original_index < length, "invalid method ordering index");
3186         sum += original_index;
3187       }
3188       // Verify sum of indices 0,1,...,length-1
3189       guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum");
3190     } else {
3191       guarantee(length == 0, "invalid method ordering length");
3192     }
3193   }
3194 
3195   // Verify default methods
3196   if (default_methods() != NULL) {
3197     Array<Method*>* methods = this->default_methods();
3198     for (int j = 0; j < methods->length(); j++) {
3199       guarantee(methods->at(j)->is_method(), "non-method in methods array");
3200     }
3201     for (int j = 0; j < methods->length() - 1; j++) {
3202       Method* m1 = methods->at(j);
3203       Method* m2 = methods->at(j + 1);
3204       guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3205     }
3206   }
3207 
3208   // Verify JNI static field identifiers
3209   if (jni_ids() != NULL) {
3210     jni_ids()->verify(this);
3211   }
3212 
3213   // Verify other fields
3214   if (array_klasses() != NULL) {
3215     guarantee(array_klasses()->is_klass(), "should be klass");
3216   }
3217   if (constants() != NULL) {
3218     guarantee(constants()->is_constantPool(), "should be constant pool");
3219   }
3220   const Klass* host = host_klass();
3221   if (host != NULL) {
3222     guarantee(host->is_klass(), "should be klass");
3223   }
3224 }
3225 
3226 void InstanceKlass::oop_verify_on(oop obj, outputStream* st) {
3227   Klass::oop_verify_on(obj, st);
3228   VerifyFieldClosure blk;
3229   obj->oop_iterate_no_header(&blk);
3230 }
3231 
3232 
3233 // JNIid class for jfieldIDs only
3234 // Note to reviewers:
3235 // These JNI functions are just moved over to column 1 and not changed
3236 // in the compressed oops workspace.
3237 JNIid::JNIid(Klass* holder, int offset, JNIid* next) {
3238   _holder = holder;
3239   _offset = offset;
3240   _next = next;
3241   debug_only(_is_static_field_id = false;)
3242 }
3243 
3244 
3245 JNIid* JNIid::find(int offset) {
3246   JNIid* current = this;
3247   while (current != NULL) {
3248     if (current->offset() == offset) return current;
3249     current = current->next();
3250   }
3251   return NULL;
3252 }
3253 
3254 void JNIid::deallocate(JNIid* current) {
3255   while (current != NULL) {
3256     JNIid* next = current->next();
3257     delete current;
3258     current = next;
3259   }
3260 }
3261 
3262 
3263 void JNIid::verify(Klass* holder) {
3264   int first_field_offset  = InstanceMirrorKlass::offset_of_static_fields();
3265   int end_field_offset;
3266   end_field_offset = first_field_offset + (InstanceKlass::cast(holder)->static_field_size() * wordSize);
3267 
3268   JNIid* current = this;
3269   while (current != NULL) {
3270     guarantee(current->holder() == holder, "Invalid klass in JNIid");
3271 #ifdef ASSERT
3272     int o = current->offset();
3273     if (current->is_static_field_id()) {
3274       guarantee(o >= first_field_offset  && o < end_field_offset,  "Invalid static field offset in JNIid");
3275     }
3276 #endif
3277     current = current->next();
3278   }
3279 }
3280 
3281 
3282 #ifdef ASSERT
3283 void InstanceKlass::set_init_state(ClassState state) {
3284   bool good_state = is_shared() ? (_init_state <= state)
3285                                                : (_init_state < state);
3286   assert(good_state || state == allocated, "illegal state transition");
3287   _init_state = (u1)state;
3288 }
3289 #endif
3290 
3291 
3292 
3293 // RedefineClasses() support for previous versions:
3294 int InstanceKlass::_previous_version_count = 0;
3295 
3296 // Purge previous versions before adding new previous versions of the class.
3297 void InstanceKlass::purge_previous_versions(InstanceKlass* ik) {
3298   if (ik->previous_versions() != NULL) {
3299     // This klass has previous versions so see what we can cleanup
3300     // while it is safe to do so.
3301 
3302     int deleted_count = 0;    // leave debugging breadcrumbs
3303     int live_count = 0;
3304     ClassLoaderData* loader_data = ik->class_loader_data();
3305     assert(loader_data != NULL, "should never be null");
3306 
3307     // RC_TRACE macro has an embedded ResourceMark
3308     RC_TRACE(0x00000200, ("purge: %s: previous versions", ik->external_name()));
3309 
3310     // previous versions are linked together through the InstanceKlass
3311     InstanceKlass* pv_node = ik->previous_versions();
3312     InstanceKlass* last = ik;
3313     int version = 0;
3314 
3315     // check the previous versions list
3316     for (; pv_node != NULL; ) {
3317 
3318       ConstantPool* pvcp = pv_node->constants();
3319       assert(pvcp != NULL, "cp ref was unexpectedly cleared");
3320 
3321       if (!pvcp->on_stack()) {
3322         // If the constant pool isn't on stack, none of the methods
3323         // are executing.  Unlink this previous_version.
3324         // The previous version InstanceKlass is on the ClassLoaderData deallocate list
3325         // so will be deallocated during the next phase of class unloading.
3326         RC_TRACE(0x00000200, ("purge: previous version " INTPTR_FORMAT " is dead",
3327                               p2i(pv_node)));
3328         // For debugging purposes.
3329         pv_node->set_is_scratch_class();
3330         pv_node->class_loader_data()->add_to_deallocate_list(pv_node);
3331         pv_node = pv_node->previous_versions();
3332         last->link_previous_versions(pv_node);
3333         deleted_count++;
3334         version++;
3335         continue;
3336       } else {
3337         RC_TRACE(0x00000200, ("purge: previous version " INTPTR_FORMAT " is alive",
3338                               p2i(pv_node)));
3339         assert(pvcp->pool_holder() != NULL, "Constant pool with no holder");
3340         guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack");
3341         live_count++;
3342       }
3343 
3344       // At least one method is live in this previous version.
3345       // Reset dead EMCP methods not to get breakpoints.
3346       // All methods are deallocated when all of the methods for this class are no
3347       // longer running.
3348       Array<Method*>* method_refs = pv_node->methods();
3349       if (method_refs != NULL) {
3350         RC_TRACE(0x00000200, ("purge: previous methods length=%d",
3351           method_refs->length()));
3352         for (int j = 0; j < method_refs->length(); j++) {
3353           Method* method = method_refs->at(j);
3354 
3355           if (!method->on_stack()) {
3356             // no breakpoints for non-running methods
3357             if (method->is_running_emcp()) {
3358               method->set_running_emcp(false);
3359             }
3360           } else {
3361             assert (method->is_obsolete() || method->is_running_emcp(),
3362                     "emcp method cannot run after emcp bit is cleared");
3363             // RC_TRACE macro has an embedded ResourceMark
3364             RC_TRACE(0x00000200,
3365               ("purge: %s(%s): prev method @%d in version @%d is alive",
3366               method->name()->as_C_string(),
3367               method->signature()->as_C_string(), j, version));
3368           }
3369         }
3370       }
3371       // next previous version
3372       last = pv_node;
3373       pv_node = pv_node->previous_versions();
3374       version++;
3375     }
3376     RC_TRACE(0x00000200,
3377       ("purge: previous version stats: live=%d, deleted=%d", live_count,
3378       deleted_count));
3379   }
3380 }
3381 
3382 void InstanceKlass::mark_newly_obsolete_methods(Array<Method*>* old_methods,
3383                                                 int emcp_method_count) {
3384   int obsolete_method_count = old_methods->length() - emcp_method_count;
3385 
3386   if (emcp_method_count != 0 && obsolete_method_count != 0 &&
3387       _previous_versions != NULL) {
3388     // We have a mix of obsolete and EMCP methods so we have to
3389     // clear out any matching EMCP method entries the hard way.
3390     int local_count = 0;
3391     for (int i = 0; i < old_methods->length(); i++) {
3392       Method* old_method = old_methods->at(i);
3393       if (old_method->is_obsolete()) {
3394         // only obsolete methods are interesting
3395         Symbol* m_name = old_method->name();
3396         Symbol* m_signature = old_method->signature();
3397 
3398         // previous versions are linked together through the InstanceKlass
3399         int j = 0;
3400         for (InstanceKlass* prev_version = _previous_versions;
3401              prev_version != NULL;
3402              prev_version = prev_version->previous_versions(), j++) {
3403 
3404           Array<Method*>* method_refs = prev_version->methods();
3405           for (int k = 0; k < method_refs->length(); k++) {
3406             Method* method = method_refs->at(k);
3407 
3408             if (!method->is_obsolete() &&
3409                 method->name() == m_name &&
3410                 method->signature() == m_signature) {
3411               // The current RedefineClasses() call has made all EMCP
3412               // versions of this method obsolete so mark it as obsolete
3413               RC_TRACE(0x00000400,
3414                 ("add: %s(%s): flush obsolete method @%d in version @%d",
3415                 m_name->as_C_string(), m_signature->as_C_string(), k, j));
3416 
3417               method->set_is_obsolete();
3418               break;
3419             }
3420           }
3421 
3422           // The previous loop may not find a matching EMCP method, but
3423           // that doesn't mean that we can optimize and not go any
3424           // further back in the PreviousVersion generations. The EMCP
3425           // method for this generation could have already been made obsolete,
3426           // but there still may be an older EMCP method that has not
3427           // been made obsolete.
3428         }
3429 
3430         if (++local_count >= obsolete_method_count) {
3431           // no more obsolete methods so bail out now
3432           break;
3433         }
3434       }
3435     }
3436   }
3437 }
3438 
3439 // Save the scratch_class as the previous version if any of the methods are running.
3440 // The previous_versions are used to set breakpoints in EMCP methods and they are
3441 // also used to clean MethodData links to redefined methods that are no longer running.
3442 void InstanceKlass::add_previous_version(instanceKlassHandle scratch_class,
3443                                          int emcp_method_count) {
3444   assert(Thread::current()->is_VM_thread(),
3445          "only VMThread can add previous versions");
3446 
3447   // RC_TRACE macro has an embedded ResourceMark
3448   RC_TRACE(0x00000400, ("adding previous version ref for %s, EMCP_cnt=%d",
3449     scratch_class->external_name(), emcp_method_count));
3450 
3451   // Clean out old previous versions
3452   purge_previous_versions(this);
3453 
3454   // Mark newly obsolete methods in remaining previous versions.  An EMCP method from
3455   // a previous redefinition may be made obsolete by this redefinition.
3456   Array<Method*>* old_methods = scratch_class->methods();
3457   mark_newly_obsolete_methods(old_methods, emcp_method_count);
3458 
3459   // If the constant pool for this previous version of the class
3460   // is not marked as being on the stack, then none of the methods
3461   // in this previous version of the class are on the stack so
3462   // we don't need to add this as a previous version.
3463   ConstantPool* cp_ref = scratch_class->constants();
3464   if (!cp_ref->on_stack()) {
3465     RC_TRACE(0x00000400, ("add: scratch class not added; no methods are running"));
3466     // For debugging purposes.
3467     scratch_class->set_is_scratch_class();
3468     scratch_class->class_loader_data()->add_to_deallocate_list(scratch_class());
3469     // Update count for class unloading.
3470     _previous_version_count--;
3471     return;
3472   }
3473 
3474   if (emcp_method_count != 0) {
3475     // At least one method is still running, check for EMCP methods
3476     for (int i = 0; i < old_methods->length(); i++) {
3477       Method* old_method = old_methods->at(i);
3478       if (!old_method->is_obsolete() && old_method->on_stack()) {
3479         // if EMCP method (not obsolete) is on the stack, mark as EMCP so that
3480         // we can add breakpoints for it.
3481 
3482         // We set the method->on_stack bit during safepoints for class redefinition
3483         // and use this bit to set the is_running_emcp bit.
3484         // After the safepoint, the on_stack bit is cleared and the running emcp
3485         // method may exit.   If so, we would set a breakpoint in a method that
3486         // is never reached, but this won't be noticeable to the programmer.
3487         old_method->set_running_emcp(true);
3488         RC_TRACE(0x00000400, ("add: EMCP method %s is on_stack " INTPTR_FORMAT,
3489                               old_method->name_and_sig_as_C_string(), p2i(old_method)));
3490       } else if (!old_method->is_obsolete()) {
3491         RC_TRACE(0x00000400, ("add: EMCP method %s is NOT on_stack " INTPTR_FORMAT,
3492                               old_method->name_and_sig_as_C_string(), p2i(old_method)));
3493       }
3494     }
3495   }
3496 
3497   // Add previous version if any methods are still running.
3498   RC_TRACE(0x00000400, ("add: scratch class added; one of its methods is on_stack"));
3499   assert(scratch_class->previous_versions() == NULL, "shouldn't have a previous version");
3500   scratch_class->link_previous_versions(previous_versions());
3501   link_previous_versions(scratch_class());
3502   // Update count for class unloading.
3503   _previous_version_count++;
3504 } // end add_previous_version()
3505 
3506 
3507 Method* InstanceKlass::method_with_idnum(int idnum) {
3508   Method* m = NULL;
3509   if (idnum < methods()->length()) {
3510     m = methods()->at(idnum);
3511   }
3512   if (m == NULL || m->method_idnum() != idnum) {
3513     for (int index = 0; index < methods()->length(); ++index) {
3514       m = methods()->at(index);
3515       if (m->method_idnum() == idnum) {
3516         return m;
3517       }
3518     }
3519     // None found, return null for the caller to handle.
3520     return NULL;
3521   }
3522   return m;
3523 }
3524 
3525 
3526 Method* InstanceKlass::method_with_orig_idnum(int idnum) {
3527   if (idnum >= methods()->length()) {
3528     return NULL;
3529   }
3530   Method* m = methods()->at(idnum);
3531   if (m != NULL && m->orig_method_idnum() == idnum) {
3532     return m;
3533   }
3534   // Obsolete method idnum does not match the original idnum
3535   for (int index = 0; index < methods()->length(); ++index) {
3536     m = methods()->at(index);
3537     if (m->orig_method_idnum() == idnum) {
3538       return m;
3539     }
3540   }
3541   // None found, return null for the caller to handle.
3542   return NULL;
3543 }
3544 
3545 
3546 Method* InstanceKlass::method_with_orig_idnum(int idnum, int version) {
3547   InstanceKlass* holder = get_klass_version(version);
3548   if (holder == NULL) {
3549     return NULL; // The version of klass is gone, no method is found
3550   }
3551   Method* method = holder->method_with_orig_idnum(idnum);
3552   return method;
3553 }
3554 
3555 
3556 jint InstanceKlass::get_cached_class_file_len() {
3557   return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file);
3558 }
3559 
3560 unsigned char * InstanceKlass::get_cached_class_file_bytes() {
3561   return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file);
3562 }
3563 
3564 
3565 /////////////// Unit tests ///////////////
3566 
3567 #ifndef PRODUCT
3568 
3569 class TestNmethodBucketContext {
3570  public:
3571   nmethod* _nmethodLast;
3572   nmethod* _nmethodMiddle;
3573   nmethod* _nmethodFirst;
3574 
3575   nmethodBucket* _bucketLast;
3576   nmethodBucket* _bucketMiddle;
3577   nmethodBucket* _bucketFirst;
3578 
3579   nmethodBucket* _bucketList;
3580 
3581   TestNmethodBucketContext() {
3582     CodeCache_lock->lock_without_safepoint_check();
3583 
3584     _nmethodLast   = reinterpret_cast<nmethod*>(0x8 * 0);
3585     _nmethodMiddle = reinterpret_cast<nmethod*>(0x8 * 1);
3586     _nmethodFirst  = reinterpret_cast<nmethod*>(0x8 * 2);
3587 
3588     _bucketLast   = new nmethodBucket(_nmethodLast,   NULL);
3589     _bucketMiddle = new nmethodBucket(_nmethodMiddle, _bucketLast);
3590     _bucketFirst  = new nmethodBucket(_nmethodFirst,   _bucketMiddle);
3591 
3592     _bucketList = _bucketFirst;
3593   }
3594 
3595   ~TestNmethodBucketContext() {
3596     delete _bucketLast;
3597     delete _bucketMiddle;
3598     delete _bucketFirst;
3599 
3600     CodeCache_lock->unlock();
3601   }
3602 };
3603 
3604 class TestNmethodBucket {
3605  public:
3606   static void testRemoveDependentNmethodFirstDeleteImmediately() {
3607     TestNmethodBucketContext c;
3608 
3609     nmethodBucket::remove_dependent_nmethod(&c._bucketList, c._nmethodFirst, true /* delete */);
3610 
3611     assert(c._bucketList == c._bucketMiddle, "check");
3612     assert(c._bucketList->next() == c._bucketLast, "check");
3613     assert(c._bucketList->next()->next() == NULL, "check");
3614 
3615     // Cleanup before context is deleted.
3616     c._bucketFirst = NULL;
3617   }
3618 
3619   static void testRemoveDependentNmethodMiddleDeleteImmediately() {
3620     TestNmethodBucketContext c;
3621 
3622     nmethodBucket::remove_dependent_nmethod(&c._bucketList, c._nmethodMiddle, true /* delete */);
3623 
3624     assert(c._bucketList == c._bucketFirst, "check");
3625     assert(c._bucketList->next() == c._bucketLast, "check");
3626     assert(c._bucketList->next()->next() == NULL, "check");
3627 
3628     // Cleanup before context is deleted.
3629     c._bucketMiddle = NULL;
3630   }
3631 
3632   static void testRemoveDependentNmethodLastDeleteImmediately() {
3633     TestNmethodBucketContext c;
3634 
3635     nmethodBucket::remove_dependent_nmethod(&c._bucketList, c._nmethodLast, true /* delete */);
3636 
3637     assert(c._bucketList == c._bucketFirst, "check");
3638     assert(c._bucketList->next() == c._bucketMiddle, "check");
3639     assert(c._bucketList->next()->next() == NULL, "check");
3640 
3641     // Cleanup before context is deleted.
3642     c._bucketLast = NULL;
3643   }
3644 
3645   static void testRemoveDependentNmethodFirstDeleteDeferred() {
3646     TestNmethodBucketContext c;
3647 
3648     nmethodBucket::remove_dependent_nmethod(&c._bucketList, c._nmethodFirst, false /* delete */);
3649 
3650     assert(c._bucketList                         == c._bucketFirst,  "check");
3651     assert(c._bucketList->next()                 == c._bucketMiddle, "check");
3652     assert(c._bucketList->next()->next()         == c._bucketLast,   "check");
3653     assert(c._bucketList->next()->next()->next() == NULL,            "check");
3654 
3655     assert(c._bucketFirst->count()  == 0, "check");
3656     assert(c._bucketMiddle->count() == 1, "check");
3657     assert(c._bucketLast->count()   == 1, "check");
3658   }
3659 
3660   static void testRemoveDependentNmethodMiddleDeleteDeferred() {
3661     TestNmethodBucketContext c;
3662 
3663     nmethodBucket::remove_dependent_nmethod(&c._bucketList, c._nmethodMiddle, false /* delete */);
3664 
3665     assert(c._bucketList                         == c._bucketFirst,  "check");
3666     assert(c._bucketList->next()                 == c._bucketMiddle, "check");
3667     assert(c._bucketList->next()->next()         == c._bucketLast,   "check");
3668     assert(c._bucketList->next()->next()->next() == NULL,            "check");
3669 
3670     assert(c._bucketFirst->count()  == 1, "check");
3671     assert(c._bucketMiddle->count() == 0, "check");
3672     assert(c._bucketLast->count()   == 1, "check");
3673   }
3674 
3675   static void testRemoveDependentNmethodLastDeleteDeferred() {
3676     TestNmethodBucketContext c;
3677 
3678     nmethodBucket::remove_dependent_nmethod(&c._bucketList, c._nmethodLast, false /* delete */);
3679 
3680     assert(c._bucketList                         == c._bucketFirst,  "check");
3681     assert(c._bucketList->next()                 == c._bucketMiddle, "check");
3682     assert(c._bucketList->next()->next()         == c._bucketLast,   "check");
3683     assert(c._bucketList->next()->next()->next() == NULL,            "check");
3684 
3685     assert(c._bucketFirst->count()  == 1, "check");
3686     assert(c._bucketMiddle->count() == 1, "check");
3687     assert(c._bucketLast->count()   == 0, "check");
3688   }
3689 
3690   static void testRemoveDependentNmethodConvenienceFirst() {
3691     TestNmethodBucketContext c;
3692 
3693     nmethodBucket::remove_dependent_nmethod(c._bucketList, c._nmethodFirst);
3694 
3695     assert(c._bucketList                         == c._bucketFirst,  "check");
3696     assert(c._bucketList->next()                 == c._bucketMiddle, "check");
3697     assert(c._bucketList->next()->next()         == c._bucketLast,   "check");
3698     assert(c._bucketList->next()->next()->next() == NULL,            "check");
3699 
3700     assert(c._bucketFirst->count()  == 0, "check");
3701     assert(c._bucketMiddle->count() == 1, "check");
3702     assert(c._bucketLast->count()   == 1, "check");
3703   }
3704 
3705   static void testRemoveDependentNmethodConvenienceMiddle() {
3706     TestNmethodBucketContext c;
3707 
3708     nmethodBucket::remove_dependent_nmethod(c._bucketList, c._nmethodMiddle);
3709 
3710     assert(c._bucketList                         == c._bucketFirst,  "check");
3711     assert(c._bucketList->next()                 == c._bucketMiddle, "check");
3712     assert(c._bucketList->next()->next()         == c._bucketLast,   "check");
3713     assert(c._bucketList->next()->next()->next() == NULL,            "check");
3714 
3715     assert(c._bucketFirst->count()  == 1, "check");
3716     assert(c._bucketMiddle->count() == 0, "check");
3717     assert(c._bucketLast->count()   == 1, "check");
3718   }
3719 
3720   static void testRemoveDependentNmethodConvenienceLast() {
3721     TestNmethodBucketContext c;
3722 
3723     nmethodBucket::remove_dependent_nmethod(c._bucketList, c._nmethodLast);
3724 
3725     assert(c._bucketList                         == c._bucketFirst,  "check");
3726     assert(c._bucketList->next()                 == c._bucketMiddle, "check");
3727     assert(c._bucketList->next()->next()         == c._bucketLast,   "check");
3728     assert(c._bucketList->next()->next()->next() == NULL,            "check");
3729 
3730     assert(c._bucketFirst->count()  == 1, "check");
3731     assert(c._bucketMiddle->count() == 1, "check");
3732     assert(c._bucketLast->count()   == 0, "check");
3733   }
3734 
3735   static void testRemoveDependentNmethod() {
3736     testRemoveDependentNmethodFirstDeleteImmediately();
3737     testRemoveDependentNmethodMiddleDeleteImmediately();
3738     testRemoveDependentNmethodLastDeleteImmediately();
3739 
3740     testRemoveDependentNmethodFirstDeleteDeferred();
3741     testRemoveDependentNmethodMiddleDeleteDeferred();
3742     testRemoveDependentNmethodLastDeleteDeferred();
3743 
3744     testRemoveDependentNmethodConvenienceFirst();
3745     testRemoveDependentNmethodConvenienceMiddle();
3746     testRemoveDependentNmethodConvenienceLast();
3747   }
3748 
3749   static void test() {
3750     testRemoveDependentNmethod();
3751   }
3752 };
3753 
3754 void TestNmethodBucket_test() {
3755   TestNmethodBucket::test();
3756 }
3757 
3758 #endif