1 /*
   2  * Copyright (c) 1997, 2016, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #include "precompiled.hpp"
  26 #include "classfile/classFileParser.hpp"
  27 #include "classfile/classFileStream.hpp"
  28 #include "classfile/javaClasses.hpp"
  29 #include "classfile/systemDictionary.hpp"
  30 #include "classfile/verifier.hpp"
  31 #include "classfile/vmSymbols.hpp"
  32 #include "code/dependencyContext.hpp"
  33 #include "compiler/compileBroker.hpp"
  34 #include "gc/shared/collectedHeap.inline.hpp"
  35 #include "gc/shared/specialized_oop_closures.hpp"
  36 #include "interpreter/oopMapCache.hpp"
  37 #include "interpreter/rewriter.hpp"
  38 #include "jvmtifiles/jvmti.h"
  39 #include "logging/log.hpp"
  40 #include "memory/heapInspection.hpp"
  41 #include "memory/iterator.inline.hpp"
  42 #include "memory/metadataFactory.hpp"
  43 #include "memory/oopFactory.hpp"
  44 #include "oops/fieldStreams.hpp"
  45 #include "oops/instanceClassLoaderKlass.hpp"
  46 #include "oops/instanceKlass.inline.hpp"
  47 #include "oops/instanceMirrorKlass.hpp"
  48 #include "oops/instanceOop.hpp"
  49 #include "oops/klass.inline.hpp"
  50 #include "oops/method.hpp"
  51 #include "oops/oop.inline.hpp"
  52 #include "oops/symbol.hpp"
  53 #include "oops/valueKlass.hpp"
  54 #include "prims/jvmtiExport.hpp"
  55 #include "prims/jvmtiRedefineClasses.hpp"
  56 #include "prims/jvmtiRedefineClassesTrace.hpp"
  57 #include "prims/jvmtiThreadState.hpp"
  58 #include "prims/methodComparator.hpp"
  59 #include "runtime/atomic.inline.hpp"
  60 #include "runtime/fieldDescriptor.hpp"
  61 #include "runtime/handles.inline.hpp"
  62 #include "runtime/javaCalls.hpp"
  63 #include "runtime/mutexLocker.hpp"
  64 #include "runtime/orderAccess.inline.hpp"
  65 #include "runtime/thread.inline.hpp"
  66 #include "services/classLoadingService.hpp"
  67 #include "services/threadService.hpp"
  68 #include "utilities/dtrace.hpp"
  69 #include "utilities/macros.hpp"
  70 #include "logging/log.hpp"
  71 #ifdef COMPILER1
  72 #include "c1/c1_Compiler.hpp"
  73 #endif
  74 
  75 #ifdef DTRACE_ENABLED
  76 
  77 
  78 #define HOTSPOT_CLASS_INITIALIZATION_required HOTSPOT_CLASS_INITIALIZATION_REQUIRED
  79 #define HOTSPOT_CLASS_INITIALIZATION_recursive HOTSPOT_CLASS_INITIALIZATION_RECURSIVE
  80 #define HOTSPOT_CLASS_INITIALIZATION_concurrent HOTSPOT_CLASS_INITIALIZATION_CONCURRENT
  81 #define HOTSPOT_CLASS_INITIALIZATION_erroneous HOTSPOT_CLASS_INITIALIZATION_ERRONEOUS
  82 #define HOTSPOT_CLASS_INITIALIZATION_super__failed HOTSPOT_CLASS_INITIALIZATION_SUPER_FAILED
  83 #define HOTSPOT_CLASS_INITIALIZATION_clinit HOTSPOT_CLASS_INITIALIZATION_CLINIT
  84 #define HOTSPOT_CLASS_INITIALIZATION_error HOTSPOT_CLASS_INITIALIZATION_ERROR
  85 #define HOTSPOT_CLASS_INITIALIZATION_end HOTSPOT_CLASS_INITIALIZATION_END
  86 #define DTRACE_CLASSINIT_PROBE(type, clss, thread_type)          \
  87   {                                                              \
  88     char* data = NULL;                                           \
  89     int len = 0;                                                 \
  90     Symbol* name = (clss)->name();                               \
  91     if (name != NULL) {                                          \
  92       data = (char*)name->bytes();                               \
  93       len = name->utf8_length();                                 \
  94     }                                                            \
  95     HOTSPOT_CLASS_INITIALIZATION_##type(                         \
  96       data, len, (clss)->class_loader(), thread_type);           \
  97   }
  98 
  99 #define DTRACE_CLASSINIT_PROBE_WAIT(type, clss, thread_type, wait) \
 100   {                                                              \
 101     char* data = NULL;                                           \
 102     int len = 0;                                                 \
 103     Symbol* name = (clss)->name();                               \
 104     if (name != NULL) {                                          \
 105       data = (char*)name->bytes();                               \
 106       len = name->utf8_length();                                 \
 107     }                                                            \
 108     HOTSPOT_CLASS_INITIALIZATION_##type(                         \
 109       data, len, (clss)->class_loader(), thread_type, wait);     \
 110   }
 111 
 112 #else //  ndef DTRACE_ENABLED
 113 
 114 #define DTRACE_CLASSINIT_PROBE(type, clss, thread_type)
 115 #define DTRACE_CLASSINIT_PROBE_WAIT(type, clss, thread_type, wait)
 116 
 117 #endif //  ndef DTRACE_ENABLED
 118 
 119 volatile int InstanceKlass::_total_instanceKlass_count = 0;
 120 
 121 static inline bool is_class_loader(const Symbol* class_name,
 122                                    const ClassFileParser& parser) {
 123   assert(class_name != NULL, "invariant");
 124 
 125   if (class_name == vmSymbols::java_lang_ClassLoader()) {
 126     return true;
 127   }
 128 
 129   if (SystemDictionary::ClassLoader_klass_loaded()) {
 130     const Klass* const super_klass = parser.super_klass();
 131     if (super_klass != NULL) {
 132       if (super_klass->is_subtype_of(SystemDictionary::ClassLoader_klass())) {
 133         return true;
 134       }
 135     }
 136   }
 137   return false;
 138 }
 139 
 140 InstanceKlass* InstanceKlass::allocate_instance_klass(const ClassFileParser& parser, TRAPS) {
 141   const int size = InstanceKlass::size(parser.vtable_size(),
 142                                        parser.itable_size(),
 143                                        nonstatic_oop_map_size(parser.total_oop_map_count()),
 144                                        parser.is_interface(),
 145                                        parser.is_anonymous());
 146 
 147   const Symbol* const class_name = parser.class_name();
 148   assert(class_name != NULL, "invariant");
 149   ClassLoaderData* loader_data = parser.loader_data();
 150   assert(loader_data != NULL, "invariant");
 151 
 152   InstanceKlass* ik;
 153 
 154   // Allocation
 155   if (REF_NONE == parser.reference_type()) {
 156     if (class_name == vmSymbols::java_lang_Class()) {
 157       // mirror
 158       ik = new (loader_data, size, THREAD) InstanceMirrorKlass(parser);
 159     }
 160     else if (is_class_loader(class_name, parser)) {
 161       // class loader
 162       ik = new (loader_data, size, THREAD) InstanceClassLoaderKlass(parser);
 163     }
 164     else if (parser.is_value_type()) {
 165       // value type
 166       ik = new (loader_data, size, THREAD) ValueKlass(parser);
 167     }
 168     else {
 169       // normal
 170       ik = new (loader_data, size, THREAD) InstanceKlass(parser, InstanceKlass::_misc_kind_other);
 171     }
 172   }
 173   else {
 174     // reference
 175     ik = new (loader_data, size, THREAD) InstanceRefKlass(parser);
 176   }
 177 
 178   // Check for pending exception before adding to the loader data and incrementing
 179   // class count.  Can get OOM here.
 180   if (HAS_PENDING_EXCEPTION) {
 181     return NULL;
 182   }
 183   assert(ik != NULL, "invariant");
 184 
 185   const bool publicize = !parser.is_internal();
 186 #ifdef ASSERT
 187   assert(ik->size() == size, "");
 188   ik->bounds_check((address) ik->start_of_vtable(), false, size);
 189   ik->bounds_check((address) ik->start_of_itable(), false, size);
 190   ik->bounds_check((address) ik->end_of_itable(), true, size);
 191   ik->bounds_check((address) ik->end_of_nonstatic_oop_maps(), true, size);
 192 #endif //ASSERT
 193 
 194   // Add all classes to our internal class loader list here,
 195   // including classes in the bootstrap (NULL) class loader.
 196   loader_data->add_class(ik, publicize);
 197   Atomic::inc(&_total_instanceKlass_count);
 198 
 199   return ik;
 200 }
 201 
 202 #ifndef PRODUCT
 203 bool InstanceKlass::bounds_check(address addr, bool edge_ok, intptr_t size_in_bytes) const {
 204   const char* bad = NULL;
 205   address end = NULL;
 206   if (addr < (address)this) {
 207     bad = "before";
 208   } else if (addr == (address)this) {
 209     if (edge_ok)  return true;
 210     bad = "just before";
 211   } else if (addr == (end = (address)this + sizeof(intptr_t) * (size_in_bytes < 0 ? size() : size_in_bytes))) {
 212     if (edge_ok)  return true;
 213     bad = "just after";
 214   } else if (addr > end) {
 215     bad = "after";
 216   } else {
 217     return true;
 218   }
 219   tty->print_cr("%s object bounds: " INTPTR_FORMAT " [" INTPTR_FORMAT ".." INTPTR_FORMAT "]",
 220                 bad, (intptr_t)addr, (intptr_t)this, (intptr_t)end);
 221   Verbose = WizardMode = true; this->print(); //@@
 222   return false;
 223 }
 224 #endif //PRODUCT
 225 
 226 // copy method ordering from resource area to Metaspace
 227 void InstanceKlass::copy_method_ordering(const intArray* m, TRAPS) {
 228   if (m != NULL) {
 229     // allocate a new array and copy contents (memcpy?)
 230     _method_ordering = MetadataFactory::new_array<int>(class_loader_data(), m->length(), CHECK);
 231     for (int i = 0; i < m->length(); i++) {
 232       _method_ordering->at_put(i, m->at(i));
 233     }
 234   } else {
 235     _method_ordering = Universe::the_empty_int_array();
 236   }
 237 }
 238 
 239 // create a new array of vtable_indices for default methods
 240 Array<int>* InstanceKlass::create_new_default_vtable_indices(int len, TRAPS) {
 241   Array<int>* vtable_indices = MetadataFactory::new_array<int>(class_loader_data(), len, CHECK_NULL);
 242   assert(default_vtable_indices() == NULL, "only create once");
 243   set_default_vtable_indices(vtable_indices);
 244   return vtable_indices;
 245 }
 246 
 247 InstanceKlass::InstanceKlass(const ClassFileParser& parser, unsigned kind) :
 248   _static_field_size(parser.static_field_size()),
 249   _nonstatic_oop_map_size(nonstatic_oop_map_size(parser.total_oop_map_count())),
 250   _itable_len(parser.itable_size()),
 251   _reference_type(parser.reference_type()) {
 252     set_vtable_length(parser.vtable_size());
 253     set_kind(kind);
 254     set_access_flags(parser.access_flags());
 255     set_is_anonymous(parser.is_anonymous());
 256     set_layout_helper(Klass::instance_layout_helper(parser.layout_size(),
 257                                                     false));
 258 
 259     assert(NULL == _methods, "underlying memory not zeroed?");
 260     assert(is_instance_klass(), "is layout incorrect?");
 261     assert(size_helper() == parser.layout_size(), "incorrect size_helper?");
 262 }
 263 
 264 void InstanceKlass::deallocate_methods(ClassLoaderData* loader_data,
 265                                        Array<Method*>* methods) {
 266   if (methods != NULL && methods != Universe::the_empty_method_array() &&
 267       !methods->is_shared()) {
 268     for (int i = 0; i < methods->length(); i++) {
 269       Method* method = methods->at(i);
 270       if (method == NULL) continue;  // maybe null if error processing
 271       // Only want to delete methods that are not executing for RedefineClasses.
 272       // The previous version will point to them so they're not totally dangling
 273       assert (!method->on_stack(), "shouldn't be called with methods on stack");
 274       MetadataFactory::free_metadata(loader_data, method);
 275     }
 276     MetadataFactory::free_array<Method*>(loader_data, methods);
 277   }
 278 }
 279 
 280 void InstanceKlass::deallocate_interfaces(ClassLoaderData* loader_data,
 281                                           const Klass* super_klass,
 282                                           Array<Klass*>* local_interfaces,
 283                                           Array<Klass*>* transitive_interfaces) {
 284   // Only deallocate transitive interfaces if not empty, same as super class
 285   // or same as local interfaces.  See code in parseClassFile.
 286   Array<Klass*>* ti = transitive_interfaces;
 287   if (ti != Universe::the_empty_klass_array() && ti != local_interfaces) {
 288     // check that the interfaces don't come from super class
 289     Array<Klass*>* sti = (super_klass == NULL) ? NULL :
 290                     InstanceKlass::cast(super_klass)->transitive_interfaces();
 291     if (ti != sti && ti != NULL && !ti->is_shared()) {
 292       MetadataFactory::free_array<Klass*>(loader_data, ti);
 293     }
 294   }
 295 
 296   // local interfaces can be empty
 297   if (local_interfaces != Universe::the_empty_klass_array() &&
 298       local_interfaces != NULL && !local_interfaces->is_shared()) {
 299     MetadataFactory::free_array<Klass*>(loader_data, local_interfaces);
 300   }
 301 }
 302 
 303 // This function deallocates the metadata and C heap pointers that the
 304 // InstanceKlass points to.
 305 void InstanceKlass::deallocate_contents(ClassLoaderData* loader_data) {
 306 
 307   // Orphan the mirror first, CMS thinks it's still live.
 308   if (java_mirror() != NULL) {
 309     java_lang_Class::set_klass(java_mirror(), NULL);
 310   }
 311 
 312   // Need to take this class off the class loader data list.
 313   loader_data->remove_class(this);
 314 
 315   // The array_klass for this class is created later, after error handling.
 316   // For class redefinition, we keep the original class so this scratch class
 317   // doesn't have an array class.  Either way, assert that there is nothing
 318   // to deallocate.
 319   assert(array_klasses() == NULL, "array classes shouldn't be created for this class yet");
 320 
 321   // Release C heap allocated data that this might point to, which includes
 322   // reference counting symbol names.
 323   release_C_heap_structures();
 324 
 325   deallocate_methods(loader_data, methods());
 326   set_methods(NULL);
 327 
 328   if (method_ordering() != NULL &&
 329       method_ordering() != Universe::the_empty_int_array() &&
 330       !method_ordering()->is_shared()) {
 331     MetadataFactory::free_array<int>(loader_data, method_ordering());
 332   }
 333   set_method_ordering(NULL);
 334 
 335   // default methods can be empty
 336   if (default_methods() != NULL &&
 337       default_methods() != Universe::the_empty_method_array() &&
 338       !default_methods()->is_shared()) {
 339     MetadataFactory::free_array<Method*>(loader_data, default_methods());
 340   }
 341   // Do NOT deallocate the default methods, they are owned by superinterfaces.
 342   set_default_methods(NULL);
 343 
 344   // default methods vtable indices can be empty
 345   if (default_vtable_indices() != NULL &&
 346       !default_vtable_indices()->is_shared()) {
 347     MetadataFactory::free_array<int>(loader_data, default_vtable_indices());
 348   }
 349   set_default_vtable_indices(NULL);
 350 
 351 
 352   // This array is in Klass, but remove it with the InstanceKlass since
 353   // this place would be the only caller and it can share memory with transitive
 354   // interfaces.
 355   if (secondary_supers() != NULL &&
 356       secondary_supers() != Universe::the_empty_klass_array() &&
 357       secondary_supers() != transitive_interfaces() &&
 358       !secondary_supers()->is_shared()) {
 359     MetadataFactory::free_array<Klass*>(loader_data, secondary_supers());
 360   }
 361   set_secondary_supers(NULL);
 362 
 363   deallocate_interfaces(loader_data, super(), local_interfaces(), transitive_interfaces());
 364   set_transitive_interfaces(NULL);
 365   set_local_interfaces(NULL);
 366 
 367   if (fields() != NULL && !fields()->is_shared()) {
 368     MetadataFactory::free_array<jushort>(loader_data, fields());
 369   }
 370   set_fields(NULL, 0);
 371 
 372   // If a method from a redefined class is using this constant pool, don't
 373   // delete it, yet.  The new class's previous version will point to this.
 374   if (constants() != NULL) {
 375     assert (!constants()->on_stack(), "shouldn't be called if anything is onstack");
 376     if (!constants()->is_shared()) {
 377       MetadataFactory::free_metadata(loader_data, constants());
 378     }
 379     // Delete any cached resolution errors for the constant pool
 380     SystemDictionary::delete_resolution_error(constants());
 381 
 382     set_constants(NULL);
 383   }
 384 
 385   if (inner_classes() != NULL &&
 386       inner_classes() != Universe::the_empty_short_array() &&
 387       !inner_classes()->is_shared()) {
 388     MetadataFactory::free_array<jushort>(loader_data, inner_classes());
 389   }
 390   set_inner_classes(NULL);
 391 
 392   // We should deallocate the Annotations instance if it's not in shared spaces.
 393   if (annotations() != NULL && !annotations()->is_shared()) {
 394     MetadataFactory::free_metadata(loader_data, annotations());
 395   }
 396   set_annotations(NULL);
 397 }
 398 
 399 bool InstanceKlass::should_be_initialized() const {
 400   return !is_initialized();
 401 }
 402 
 403 klassItable* InstanceKlass::itable() const {
 404   return new klassItable(instanceKlassHandle(this));
 405 }
 406 
 407 void InstanceKlass::eager_initialize(Thread *thread) {
 408   if (!EagerInitialization) return;
 409 
 410   if (this->is_not_initialized()) {
 411     // abort if the the class has a class initializer
 412     if (this->class_initializer() != NULL) return;
 413 
 414     // abort if it is java.lang.Object (initialization is handled in genesis)
 415     Klass* super = this->super();
 416     if (super == NULL) return;
 417 
 418     // abort if the super class should be initialized
 419     if (!InstanceKlass::cast(super)->is_initialized()) return;
 420 
 421     // call body to expose the this pointer
 422     instanceKlassHandle this_k(thread, this);
 423     eager_initialize_impl(this_k);
 424   }
 425 }
 426 
 427 // JVMTI spec thinks there are signers and protection domain in the
 428 // instanceKlass.  These accessors pretend these fields are there.
 429 // The hprof specification also thinks these fields are in InstanceKlass.
 430 oop InstanceKlass::protection_domain() const {
 431   // return the protection_domain from the mirror
 432   return java_lang_Class::protection_domain(java_mirror());
 433 }
 434 
 435 // To remove these from requires an incompatible change and CCC request.
 436 objArrayOop InstanceKlass::signers() const {
 437   // return the signers from the mirror
 438   return java_lang_Class::signers(java_mirror());
 439 }
 440 
 441 oop InstanceKlass::init_lock() const {
 442   // return the init lock from the mirror
 443   oop lock = java_lang_Class::init_lock(java_mirror());
 444   // Prevent reordering with any access of initialization state
 445   OrderAccess::loadload();
 446   assert((oop)lock != NULL || !is_not_initialized(), // initialized or in_error state
 447          "only fully initialized state can have a null lock");
 448   return lock;
 449 }
 450 
 451 // Set the initialization lock to null so the object can be GC'ed.  Any racing
 452 // threads to get this lock will see a null lock and will not lock.
 453 // That's okay because they all check for initialized state after getting
 454 // the lock and return.
 455 void InstanceKlass::fence_and_clear_init_lock() {
 456   // make sure previous stores are all done, notably the init_state.
 457   OrderAccess::storestore();
 458   java_lang_Class::set_init_lock(java_mirror(), NULL);
 459   assert(!is_not_initialized(), "class must be initialized now");
 460 }
 461 
 462 void InstanceKlass::eager_initialize_impl(instanceKlassHandle this_k) {
 463   EXCEPTION_MARK;
 464   oop init_lock = this_k->init_lock();
 465   ObjectLocker ol(init_lock, THREAD, init_lock != NULL);
 466 
 467   // abort if someone beat us to the initialization
 468   if (!this_k->is_not_initialized()) return;  // note: not equivalent to is_initialized()
 469 
 470   ClassState old_state = this_k->init_state();
 471   link_class_impl(this_k, true, THREAD);
 472   if (HAS_PENDING_EXCEPTION) {
 473     CLEAR_PENDING_EXCEPTION;
 474     // Abort if linking the class throws an exception.
 475 
 476     // Use a test to avoid redundantly resetting the state if there's
 477     // no change.  Set_init_state() asserts that state changes make
 478     // progress, whereas here we might just be spinning in place.
 479     if( old_state != this_k->_init_state )
 480       this_k->set_init_state (old_state);
 481   } else {
 482     // linking successfull, mark class as initialized
 483     this_k->set_init_state (fully_initialized);
 484     this_k->fence_and_clear_init_lock();
 485     // trace
 486     if (log_is_enabled(Info, classinit)) {
 487       ResourceMark rm(THREAD);
 488       log_info(classinit)("[Initialized %s without side effects]", this_k->external_name());
 489     }
 490   }
 491 }
 492 
 493 
 494 // See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization
 495 // process. The step comments refers to the procedure described in that section.
 496 // Note: implementation moved to static method to expose the this pointer.
 497 void InstanceKlass::initialize(TRAPS) {
 498   if (this->should_be_initialized()) {
 499     HandleMark hm(THREAD);
 500     instanceKlassHandle this_k(THREAD, this);
 501     initialize_impl(this_k, CHECK);
 502     // Note: at this point the class may be initialized
 503     //       OR it may be in the state of being initialized
 504     //       in case of recursive initialization!
 505   } else {
 506     assert(is_initialized(), "sanity check");
 507   }
 508 }
 509 
 510 
 511 bool InstanceKlass::verify_code(
 512     instanceKlassHandle this_k, bool throw_verifyerror, TRAPS) {
 513   // 1) Verify the bytecodes
 514   Verifier::Mode mode =
 515     throw_verifyerror ? Verifier::ThrowException : Verifier::NoException;
 516   return Verifier::verify(this_k, mode, this_k->should_verify_class(), THREAD);
 517 }
 518 
 519 
 520 // Used exclusively by the shared spaces dump mechanism to prevent
 521 // classes mapped into the shared regions in new VMs from appearing linked.
 522 
 523 void InstanceKlass::unlink_class() {
 524   assert(is_linked(), "must be linked");
 525   _init_state = loaded;
 526 }
 527 
 528 void InstanceKlass::link_class(TRAPS) {
 529   assert(is_loaded(), "must be loaded");
 530   if (!is_linked()) {
 531     HandleMark hm(THREAD);
 532     instanceKlassHandle this_k(THREAD, this);
 533     link_class_impl(this_k, true, CHECK);
 534   }
 535 }
 536 
 537 // Called to verify that a class can link during initialization, without
 538 // throwing a VerifyError.
 539 bool InstanceKlass::link_class_or_fail(TRAPS) {
 540   assert(is_loaded(), "must be loaded");
 541   if (!is_linked()) {
 542     HandleMark hm(THREAD);
 543     instanceKlassHandle this_k(THREAD, this);
 544     link_class_impl(this_k, false, CHECK_false);
 545   }
 546   return is_linked();
 547 }
 548 
 549 bool InstanceKlass::link_class_impl(
 550     instanceKlassHandle this_k, bool throw_verifyerror, TRAPS) {
 551   // check for error state
 552   if (this_k->is_in_error_state()) {
 553     ResourceMark rm(THREAD);
 554     THROW_MSG_(vmSymbols::java_lang_NoClassDefFoundError(),
 555                this_k->external_name(), false);
 556   }
 557   // return if already verified
 558   if (this_k->is_linked()) {
 559     return true;
 560   }
 561 
 562   // Timing
 563   // timer handles recursion
 564   assert(THREAD->is_Java_thread(), "non-JavaThread in link_class_impl");
 565   JavaThread* jt = (JavaThread*)THREAD;
 566 
 567   // link super class before linking this class
 568   instanceKlassHandle super(THREAD, this_k->super());
 569   if (super.not_null()) {
 570     if (super->is_interface()) {  // check if super class is an interface
 571       ResourceMark rm(THREAD);
 572       Exceptions::fthrow(
 573         THREAD_AND_LOCATION,
 574         vmSymbols::java_lang_IncompatibleClassChangeError(),
 575         "class %s has interface %s as super class",
 576         this_k->external_name(),
 577         super->external_name()
 578       );
 579       return false;
 580     }
 581 
 582     link_class_impl(super, throw_verifyerror, CHECK_false);
 583   }
 584 
 585   // link all interfaces implemented by this class before linking this class
 586   Array<Klass*>* interfaces = this_k->local_interfaces();
 587   int num_interfaces = interfaces->length();
 588   for (int index = 0; index < num_interfaces; index++) {
 589     HandleMark hm(THREAD);
 590     instanceKlassHandle ih(THREAD, interfaces->at(index));
 591     link_class_impl(ih, throw_verifyerror, CHECK_false);
 592   }
 593 
 594   // If a value type is referenced by a class (either as a field type or a
 595   // method argument or return type) this value type must be loaded during
 596   // the linking of this class because size and properties of the value type
 597   // must be known in order to be able to perform value type optimizations
 598 
 599   // Note: circular dependencies between value types are not handled yet
 600 
 601   // Note: one case is not handled yet: arrays of value types => FixMe
 602 
 603   // Note: the current implementation is not optimized because the search for
 604   // value types is performed on all classes. It would be more efficient to
 605   // detect value types during verification and 'tag' the classes for which
 606   // value type loading is required. However, this optimization won't be
 607   // applicable to classes that are not verified
 608 
 609   // First step: fields
 610   for (JavaFieldStream fs(this_k); !fs.done(); fs.next()) {
 611     ResourceMark rm(THREAD);
 612     if (fs.field_descriptor().field_type() == T_VALUETYPE) {
 613       Symbol* signature = fs.field_descriptor().signature();
 614       // Get current loader and protection domain first.
 615       oop loader = this_k->class_loader();
 616       oop protection_domain = this_k->protection_domain();
 617       bool ok = SystemDictionary::resolve_or_fail(signature,
 618           Handle(THREAD, loader), Handle(THREAD, protection_domain), true,
 619           THREAD);
 620       if (!ok) {
 621         THROW_(vmSymbols::java_lang_LinkageError(), false);
 622       }
 623     }
 624   }
 625 
 626   // Second step: methods arguments and return types
 627 //  for (int i = 0; i < this_k->constants()->length(); i++) {
 628 //    if (this_k->constants()->tag_at(i).is_method()) {
 629 //      Symbol* signature = this_k->constants()->signature_ref_at(i);
 630 //      ResourceMark rm(THREAD);
 631 //      for (SignatureStream ss(signature); !ss.is_done(); ss.next()) {
 632 //        if (ss.type() == T_VALUETYPE) {
 633 //          Symbol* sig = ss.as_symbol(THREAD);
 634 //          // Get current loader and protection domain first.
 635 //          oop loader = this_k->class_loader();
 636 //          oop protection_domain = this_k->protection_domain();
 637 //
 638 //          bool ok = SystemDictionary::resolve_or_fail(sig,
 639 //              Handle(THREAD, loader), Handle(THREAD, protection_domain), true,
 640 //              THREAD);
 641 //          if (!ok) {
 642 //            THROW_(vmSymbols::java_lang_LinkageError(), false);
 643 //          }
 644 //        }
 645 //      }
 646 //    }
 647 //  }
 648 
 649   // in case the class is linked in the process of linking its superclasses
 650   if (this_k->is_linked()) {
 651     return true;
 652   }
 653   // trace only the link time for this klass that includes
 654   // the verification time
 655   PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(),
 656                              ClassLoader::perf_class_link_selftime(),
 657                              ClassLoader::perf_classes_linked(),
 658                              jt->get_thread_stat()->perf_recursion_counts_addr(),
 659                              jt->get_thread_stat()->perf_timers_addr(),
 660                              PerfClassTraceTime::CLASS_LINK);
 661 
 662   // verification & rewriting
 663   {
 664     oop init_lock = this_k->init_lock();
 665     ObjectLocker ol(init_lock, THREAD, init_lock != NULL);
 666     // rewritten will have been set if loader constraint error found
 667     // on an earlier link attempt
 668     // don't verify or rewrite if already rewritten
 669 
 670     if (!this_k->is_linked()) {
 671       if (!this_k->is_rewritten()) {
 672         {
 673           bool verify_ok = verify_code(this_k, throw_verifyerror, THREAD);
 674           if (!verify_ok) {
 675             return false;
 676           }
 677         }
 678 
 679         // Just in case a side-effect of verify linked this class already
 680         // (which can sometimes happen since the verifier loads classes
 681         // using custom class loaders, which are free to initialize things)
 682         if (this_k->is_linked()) {
 683           return true;
 684         }
 685 
 686         // also sets rewritten
 687         this_k->rewrite_class(CHECK_false);
 688       }
 689 
 690       // relocate jsrs and link methods after they are all rewritten
 691       this_k->link_methods(CHECK_false);
 692 
 693       // Initialize the vtable and interface table after
 694       // methods have been rewritten since rewrite may
 695       // fabricate new Method*s.
 696       // also does loader constraint checking
 697       if (!this_k()->is_shared()) {
 698         ResourceMark rm(THREAD);
 699         this_k->vtable()->initialize_vtable(true, CHECK_false);
 700         this_k->itable()->initialize_itable(true, CHECK_false);
 701       }
 702 #ifdef ASSERT
 703       else {
 704         ResourceMark rm(THREAD);
 705         this_k->vtable()->verify(tty, true);
 706         // In case itable verification is ever added.
 707         // this_k->itable()->verify(tty, true);
 708       }
 709 #endif
 710       // DVT/VCC linking implies linking it's partner
 711       if (this_k->is_derive_value_type()) {
 712         // Simple state check to prevent infinite link calls
 713         if (!this_k->derive_value_type_klass()->is_rewritten()) {
 714           this_k->derive_value_type_klass()->link_class(CHECK_false);
 715         }
 716       }
 717       this_k->set_init_state(linked);
 718       if (JvmtiExport::should_post_class_prepare()) {
 719         Thread *thread = THREAD;
 720         assert(thread->is_Java_thread(), "thread->is_Java_thread()");
 721         JvmtiExport::post_class_prepare((JavaThread *) thread, this_k());
 722       }
 723     }
 724   }
 725   return true;
 726 }
 727 
 728 
 729 // Rewrite the byte codes of all of the methods of a class.
 730 // The rewriter must be called exactly once. Rewriting must happen after
 731 // verification but before the first method of the class is executed.
 732 void InstanceKlass::rewrite_class(TRAPS) {
 733   assert(is_loaded(), "must be loaded");
 734   instanceKlassHandle this_k(THREAD, this);
 735   if (this_k->is_rewritten()) {
 736     assert(this_k()->is_shared(), "rewriting an unshared class?");
 737     return;
 738   }
 739   Rewriter::rewrite(this_k, CHECK);
 740   this_k->set_rewritten();
 741 }
 742 
 743 // Now relocate and link method entry points after class is rewritten.
 744 // This is outside is_rewritten flag. In case of an exception, it can be
 745 // executed more than once.
 746 void InstanceKlass::link_methods(TRAPS) {
 747   int len = methods()->length();
 748   for (int i = len-1; i >= 0; i--) {
 749     methodHandle m(THREAD, methods()->at(i));
 750 
 751     // Set up method entry points for compiler and interpreter    .
 752     m->link_method(m, CHECK);
 753   }
 754 }
 755 
 756 // Eagerly initialize superinterfaces that declare default methods (concrete instance: any access)
 757 void InstanceKlass::initialize_super_interfaces(instanceKlassHandle this_k, TRAPS) {
 758   if (this_k->has_default_methods()) {
 759     for (int i = 0; i < this_k->local_interfaces()->length(); ++i) {
 760       Klass* iface = this_k->local_interfaces()->at(i);
 761       InstanceKlass* ik = InstanceKlass::cast(iface);
 762       if (ik->should_be_initialized()) {
 763         if (ik->has_default_methods()) {
 764           ik->initialize_super_interfaces(ik, THREAD);
 765         }
 766         // Only initialize() interfaces that "declare" concrete methods.
 767         // has_default_methods drives searching superinterfaces since it
 768         // means has_default_methods in its superinterface hierarchy
 769         if (!HAS_PENDING_EXCEPTION && ik->declares_default_methods()) {
 770           ik->initialize(THREAD);
 771         }
 772         if (HAS_PENDING_EXCEPTION) {
 773           Handle e(THREAD, PENDING_EXCEPTION);
 774           CLEAR_PENDING_EXCEPTION;
 775           {
 776             EXCEPTION_MARK;
 777             // Locks object, set state, and notify all waiting threads
 778             this_k->set_initialization_state_and_notify(
 779                 initialization_error, THREAD);
 780 
 781             // ignore any exception thrown, superclass initialization error is
 782             // thrown below
 783             CLEAR_PENDING_EXCEPTION;
 784           }
 785           THROW_OOP(e());
 786         }
 787       }
 788     }
 789   }
 790 }
 791 
 792 void InstanceKlass::initialize_impl(instanceKlassHandle this_k, TRAPS) {
 793   // ensure outer VCC is initialized, possible some crafty code referred to VT 1st
 794   if (this_k->is_derive_value_type() && this_k->is_value()) {
 795     this_k->derive_value_type_klass()->initialize(CHECK);
 796   }
 797   // Make sure klass is linked (verified) before initialization
 798   // A class could already be verified, since it has been reflected upon.
 799   this_k->link_class(CHECK);
 800 
 801 //  DTRACE_CLASSINIT_PROBE(required, this_k(), -1);
 802 
 803   bool wait = false;
 804 
 805   // refer to the JVM book page 47 for description of steps
 806   // Step 1
 807   {
 808     oop init_lock = this_k->init_lock();
 809     ObjectLocker ol(init_lock, THREAD, init_lock != NULL);
 810 
 811     Thread *self = THREAD; // it's passed the current thread
 812 
 813     // Step 2
 814     // If we were to use wait() instead of waitInterruptibly() then
 815     // we might end up throwing IE from link/symbol resolution sites
 816     // that aren't expected to throw.  This would wreak havoc.  See 6320309.
 817     while(this_k->is_being_initialized() && !this_k->is_reentrant_initialization(self)) {
 818         wait = true;
 819       ol.waitUninterruptibly(CHECK);
 820     }
 821 
 822     // Step 3
 823     if (this_k->is_being_initialized() && this_k->is_reentrant_initialization(self)) {
 824 //      DTRACE_CLASSINIT_PROBE_WAIT(recursive, this_k(), -1,wait);
 825       return;
 826     }
 827 
 828     // Step 4
 829     if (this_k->is_initialized()) {
 830 //      DTRACE_CLASSINIT_PROBE_WAIT(concurrent, this_k(), -1,wait);
 831       return;
 832     }
 833 
 834     // Step 5
 835     if (this_k->is_in_error_state()) {
 836 //      DTRACE_CLASSINIT_PROBE_WAIT(erroneous, this_k(), -1,wait);
 837       ResourceMark rm(THREAD);
 838       const char* desc = "Could not initialize class ";
 839       const char* className = this_k->external_name();
 840       size_t msglen = strlen(desc) + strlen(className) + 1;
 841       char* message = NEW_RESOURCE_ARRAY(char, msglen);
 842       if (NULL == message) {
 843         // Out of memory: can't create detailed error message
 844         THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), className);
 845       } else {
 846         jio_snprintf(message, msglen, "%s%s", desc, className);
 847         THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), message);
 848       }
 849     }
 850 
 851     // Step 6
 852     this_k->set_init_state(being_initialized);
 853     this_k->set_init_thread(self);
 854   }
 855 
 856   // Step 7
 857   Klass* super_klass = this_k->super();
 858   if (super_klass != NULL && !this_k->is_interface() && super_klass->should_be_initialized()) {
 859     super_klass->initialize(THREAD);
 860 
 861     if (HAS_PENDING_EXCEPTION) {
 862       Handle e(THREAD, PENDING_EXCEPTION);
 863       CLEAR_PENDING_EXCEPTION;
 864       {
 865         EXCEPTION_MARK;
 866         this_k->set_initialization_state_and_notify(initialization_error, THREAD); // Locks object, set state, and notify all waiting threads
 867         CLEAR_PENDING_EXCEPTION;   // ignore any exception thrown, superclass initialization error is thrown below
 868       }
 869 //      DTRACE_CLASSINIT_PROBE_WAIT(super__failed, this_k(), -1,wait);
 870       THROW_OOP(e());
 871     }
 872   }
 873 
 874   // If C is an interface that declares a non-abstract, non-static method,
 875   // the initialization of a class (not an interface) that implements C directly or
 876   // indirectly.
 877   // Recursively initialize any superinterfaces that declare default methods
 878   // Only need to recurse if has_default_methods which includes declaring and
 879   // inheriting default methods
 880   if (!this_k->is_interface() && this_k->has_default_methods()) {
 881     this_k->initialize_super_interfaces(this_k, CHECK);
 882   }
 883 
 884   // Step 8
 885   {
 886     assert(THREAD->is_Java_thread(), "non-JavaThread in initialize_impl");
 887     JavaThread* jt = (JavaThread*)THREAD;
 888 //    DTRACE_CLASSINIT_PROBE_WAIT(clinit, this_k(), -1,wait);
 889     // Timer includes any side effects of class initialization (resolution,
 890     // etc), but not recursive entry into call_class_initializer().
 891     PerfClassTraceTime timer(ClassLoader::perf_class_init_time(),
 892                              ClassLoader::perf_class_init_selftime(),
 893                              ClassLoader::perf_classes_inited(),
 894                              jt->get_thread_stat()->perf_recursion_counts_addr(),
 895                              jt->get_thread_stat()->perf_timers_addr(),
 896                              PerfClassTraceTime::CLASS_CLINIT);
 897     this_k->call_class_initializer(THREAD);
 898   }
 899 
 900   // Step 9
 901   if (!HAS_PENDING_EXCEPTION) {
 902     this_k->set_initialization_state_and_notify(fully_initialized, CHECK);
 903     { ResourceMark rm(THREAD);
 904       debug_only(this_k->vtable()->verify(tty, true);)
 905     }
 906   }
 907   else {
 908     // Step 10 and 11
 909     Handle e(THREAD, PENDING_EXCEPTION);
 910     CLEAR_PENDING_EXCEPTION;
 911     // JVMTI has already reported the pending exception
 912     // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
 913     JvmtiExport::clear_detected_exception((JavaThread*)THREAD);
 914     {
 915       EXCEPTION_MARK;
 916       this_k->set_initialization_state_and_notify(initialization_error, THREAD);
 917       CLEAR_PENDING_EXCEPTION;   // ignore any exception thrown, class initialization error is thrown below
 918       // JVMTI has already reported the pending exception
 919       // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
 920       JvmtiExport::clear_detected_exception((JavaThread*)THREAD);
 921     }
 922 //    DTRACE_CLASSINIT_PROBE_WAIT(error, this_k(), -1,wait);
 923     if (e->is_a(SystemDictionary::Error_klass())) {
 924       THROW_OOP(e());
 925     } else {
 926       JavaCallArguments args(e);
 927       THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(),
 928                 vmSymbols::throwable_void_signature(),
 929                 &args);
 930     }
 931   }
 932 //  DTRACE_CLASSINIT_PROBE_WAIT(end, this_k(), -1,wait);
 933 }
 934 
 935 
 936 // Note: implementation moved to static method to expose the this pointer.
 937 void InstanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) {
 938   instanceKlassHandle kh(THREAD, this);
 939   set_initialization_state_and_notify_impl(kh, state, CHECK);
 940 }
 941 
 942 void InstanceKlass::set_initialization_state_and_notify_impl(instanceKlassHandle this_k, ClassState state, TRAPS) {
 943   oop init_lock = this_k->init_lock();
 944   ObjectLocker ol(init_lock, THREAD, init_lock != NULL);
 945   this_k->set_init_state(state);
 946   this_k->fence_and_clear_init_lock();
 947   ol.notify_all(CHECK);
 948 }
 949 
 950 // The embedded _implementor field can only record one implementor.
 951 // When there are more than one implementors, the _implementor field
 952 // is set to the interface Klass* itself. Following are the possible
 953 // values for the _implementor field:
 954 //   NULL                  - no implementor
 955 //   implementor Klass*    - one implementor
 956 //   self                  - more than one implementor
 957 //
 958 // The _implementor field only exists for interfaces.
 959 void InstanceKlass::add_implementor(Klass* k) {
 960   assert(Compile_lock->owned_by_self(), "");
 961   assert(is_interface(), "not interface");
 962   // Filter out my subinterfaces.
 963   // (Note: Interfaces are never on the subklass list.)
 964   if (InstanceKlass::cast(k)->is_interface()) return;
 965 
 966   // Filter out subclasses whose supers already implement me.
 967   // (Note: CHA must walk subclasses of direct implementors
 968   // in order to locate indirect implementors.)
 969   Klass* sk = k->super();
 970   if (sk != NULL && InstanceKlass::cast(sk)->implements_interface(this, false))
 971     // We only need to check one immediate superclass, since the
 972     // implements_interface query looks at transitive_interfaces.
 973     // Any supers of the super have the same (or fewer) transitive_interfaces.
 974     return;
 975 
 976   Klass* ik = implementor();
 977   if (ik == NULL) {
 978     set_implementor(k);
 979   } else if (ik != this) {
 980     // There is already an implementor. Use itself as an indicator of
 981     // more than one implementors.
 982     set_implementor(this);
 983   }
 984 
 985   // The implementor also implements the transitive_interfaces
 986   for (int index = 0; index < local_interfaces()->length(); index++) {
 987     InstanceKlass::cast(local_interfaces()->at(index))->add_implementor(k);
 988   }
 989 }
 990 
 991 void InstanceKlass::init_implementor() {
 992   if (is_interface()) {
 993     set_implementor(NULL);
 994   }
 995 }
 996 
 997 
 998 void InstanceKlass::process_interfaces(Thread *thread) {
 999   // link this class into the implementors list of every interface it implements
1000   for (int i = local_interfaces()->length() - 1; i >= 0; i--) {
1001     assert(local_interfaces()->at(i)->is_klass(), "must be a klass");
1002     InstanceKlass* interf = InstanceKlass::cast(local_interfaces()->at(i));
1003     assert(interf->is_interface(), "expected interface");
1004     interf->add_implementor(this);
1005   }
1006 }
1007 
1008 bool InstanceKlass::can_be_primary_super_slow() const {
1009   if (is_interface())
1010     return false;
1011   else
1012     return Klass::can_be_primary_super_slow();
1013 }
1014 
1015 GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots) {
1016   // The secondaries are the implemented interfaces.
1017   Array<Klass*>* interfaces = transitive_interfaces();
1018   int num_secondaries = num_extra_slots + interfaces->length();
1019   if (num_secondaries == 0) {
1020     // Must share this for correct bootstrapping!
1021     set_secondary_supers(Universe::the_empty_klass_array());
1022     return NULL;
1023   } else if (num_extra_slots == 0) {
1024     // The secondary super list is exactly the same as the transitive interfaces.
1025     // Redefine classes has to be careful not to delete this!
1026     set_secondary_supers(interfaces);
1027     return NULL;
1028   } else {
1029     // Copy transitive interfaces to a temporary growable array to be constructed
1030     // into the secondary super list with extra slots.
1031     GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length());
1032     for (int i = 0; i < interfaces->length(); i++) {
1033       secondaries->push(interfaces->at(i));
1034     }
1035     return secondaries;
1036   }
1037 }
1038 
1039 bool InstanceKlass::compute_is_subtype_of(Klass* k) {
1040   if (k->is_interface()) {
1041     return implements_interface(k, true);
1042   } else {
1043     return Klass::compute_is_subtype_of(k);
1044   }
1045 }
1046 
1047 bool InstanceKlass::implements_interface(Klass* k, bool search_extras) const {
1048   if (this == k) return true;
1049   assert(k->is_interface(), "should be an interface class");
1050   for (int i = 0; i < transitive_interfaces()->length(); i++) {
1051     if (transitive_interfaces()->at(i) == k) {
1052       return true;
1053     }
1054   }
1055   if (!(search_extras && EnableExtraSuper))
1056     return false;
1057 
1058   for (InstanceKlass* exs = extra_super(); exs != NULL; exs = exs->extra_super()) {
1059     if (exs->implements_interface(k, false))
1060       return true;
1061   }
1062   return false;
1063 }
1064 
1065 bool InstanceKlass::is_same_or_direct_interface(Klass *k) const {
1066   // Verify direct super interface
1067   if (this == k) return true;
1068   assert(k->is_interface(), "should be an interface class");
1069   for (int i = 0; i < local_interfaces()->length(); i++) {
1070     if (local_interfaces()->at(i) == k) {
1071       return true;
1072     }
1073   }
1074   return false;
1075 }
1076 
1077 bool InstanceKlass::can_be_used_as_extra_super(AccessFlags access_flags,
1078                                                Array<Method*>* methods,
1079                                                bool has_default_methods,
1080                                                Array<Klass*>* transitive_interfaces) {
1081   if (!EnableExtraSuper)  return false;
1082   if (!access_flags.is_interface())  return false;
1083   bool force_itable = false;
1084   // Look for any implementation methods anywhere in this interface.
1085   if (!has_default_methods) {
1086     for (int i = 0, len = transitive_interfaces->length(); i < len; i++) {
1087       if (InstanceKlass::cast(transitive_interfaces->at(i))->has_default_methods()) {
1088         has_default_methods = true;
1089         break;
1090       }
1091     }
1092   }
1093   if (has_default_methods)
1094     force_itable = true;
1095   // We could make this logic more selective if we want.
1096   return force_itable;
1097 }
1098 
1099 objArrayOop InstanceKlass::allocate_objArray(int n, int length, TRAPS) {
1100   if (length < 0) THROW_0(vmSymbols::java_lang_NegativeArraySizeException());
1101   if (length > arrayOopDesc::max_array_length(T_OBJECT)) {
1102     report_java_out_of_memory("Requested array size exceeds VM limit");
1103     JvmtiExport::post_array_size_exhausted();
1104     THROW_OOP_0(Universe::out_of_memory_error_array_size());
1105   }
1106   int size = objArrayOopDesc::object_size(length);
1107   Klass* ak = array_klass(n, CHECK_NULL);
1108   KlassHandle h_ak (THREAD, ak);
1109   objArrayOop o =
1110     (objArrayOop)CollectedHeap::array_allocate(h_ak, size, length, CHECK_NULL);
1111   return o;
1112 }
1113 
1114 instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) {
1115   if (TraceFinalizerRegistration) {
1116     tty->print("Registered ");
1117     i->print_value_on(tty);
1118     tty->print_cr(" (" INTPTR_FORMAT ") as finalizable", p2i(i));
1119   }
1120   instanceHandle h_i(THREAD, i);
1121   // Pass the handle as argument, JavaCalls::call expects oop as jobjects
1122   JavaValue result(T_VOID);
1123   JavaCallArguments args(h_i);
1124   methodHandle mh (THREAD, Universe::finalizer_register_method());
1125   JavaCalls::call(&result, mh, &args, CHECK_NULL);
1126   return h_i();
1127 }
1128 
1129 instanceOop InstanceKlass::allocate_instance(TRAPS) {
1130   bool has_finalizer_flag = has_finalizer(); // Query before possible GC
1131   int size = size_helper();  // Query before forming handle.
1132 
1133   KlassHandle h_k(THREAD, this);
1134 
1135   instanceOop i;
1136 
1137   i = (instanceOop)CollectedHeap::obj_allocate(h_k, size, CHECK_NULL);
1138   if (has_finalizer_flag && !RegisterFinalizersAtInit) {
1139     i = register_finalizer(i, CHECK_NULL);
1140   }
1141   return i;
1142 }
1143 
1144 void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) {
1145   if (is_interface() || is_abstract()) {
1146     ResourceMark rm(THREAD);
1147     THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
1148               : vmSymbols::java_lang_InstantiationException(), external_name());
1149   }
1150   if (this == SystemDictionary::Class_klass()) {
1151     ResourceMark rm(THREAD);
1152     THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError()
1153               : vmSymbols::java_lang_IllegalAccessException(), external_name());
1154   }
1155 }
1156 
1157 Klass* InstanceKlass::array_klass_impl(bool or_null, int n, TRAPS) {
1158   instanceKlassHandle this_k(THREAD, this);
1159   return array_klass_impl(this_k, or_null, n, THREAD);
1160 }
1161 
1162 Klass* InstanceKlass::array_klass_impl(instanceKlassHandle this_k, bool or_null, int n, TRAPS) {
1163   if (this_k->array_klasses() == NULL) {
1164     if (or_null) return NULL;
1165 
1166     ResourceMark rm;
1167     JavaThread *jt = (JavaThread *)THREAD;
1168     {
1169       // Atomic creation of array_klasses
1170       MutexLocker mc(Compile_lock, THREAD);   // for vtables
1171       MutexLocker ma(MultiArray_lock, THREAD);
1172 
1173       // Check if update has already taken place
1174       if (this_k->array_klasses() == NULL) {
1175         Klass*    k = ObjArrayKlass::allocate_objArray_klass(this_k->class_loader_data(), 1, this_k, CHECK_NULL);
1176         this_k->set_array_klasses(k);
1177       }
1178     }
1179   }
1180   // _this will always be set at this point
1181   ObjArrayKlass* oak = (ObjArrayKlass*)this_k->array_klasses();
1182   if (or_null) {
1183     return oak->array_klass_or_null(n);
1184   }
1185   return oak->array_klass(n, THREAD);
1186 }
1187 
1188 Klass* InstanceKlass::array_klass_impl(bool or_null, TRAPS) {
1189   return array_klass_impl(or_null, 1, THREAD);
1190 }
1191 
1192 void InstanceKlass::call_class_initializer(TRAPS) {
1193   instanceKlassHandle ik (THREAD, this);
1194   call_class_initializer_impl(ik, THREAD);
1195 }
1196 
1197 static int call_class_initializer_impl_counter = 0;   // for debugging
1198 
1199 Method* InstanceKlass::class_initializer() {
1200   Method* clinit = find_method(
1201       vmSymbols::class_initializer_name(), vmSymbols::void_method_signature());
1202   if (clinit != NULL && clinit->has_valid_initializer_flags()) {
1203     return clinit;
1204   }
1205   return NULL;
1206 }
1207 
1208 void InstanceKlass::call_class_initializer_impl(instanceKlassHandle this_k, TRAPS) {
1209   if (ReplayCompiles &&
1210       (ReplaySuppressInitializers == 1 ||
1211        ReplaySuppressInitializers >= 2 && this_k->class_loader() != NULL)) {
1212     // Hide the existence of the initializer for the purpose of replaying the compile
1213     return;
1214   }
1215 
1216   methodHandle h_method(THREAD, this_k->class_initializer());
1217   assert(!this_k->is_initialized(), "we cannot initialize twice");
1218   if (log_is_enabled(Info, classinit)) {
1219     ResourceMark rm;
1220     outputStream* log = LogHandle(classinit)::info_stream();
1221     log->print("%d Initializing ", call_class_initializer_impl_counter++);
1222     this_k->name()->print_value_on(log);
1223     log->print_cr("%s (" INTPTR_FORMAT ")", h_method() == NULL ? "(no method)" : "", p2i(this_k()));
1224   }
1225   if (h_method() != NULL) {
1226     JavaCallArguments args; // No arguments
1227     JavaValue result(T_VOID);
1228     JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args)
1229   }
1230 }
1231 
1232 
1233 void InstanceKlass::mask_for(const methodHandle& method, int bci,
1234   InterpreterOopMap* entry_for) {
1235   // Dirty read, then double-check under a lock.
1236   if (_oop_map_cache == NULL) {
1237     // Otherwise, allocate a new one.
1238     MutexLocker x(OopMapCacheAlloc_lock);
1239     // First time use. Allocate a cache in C heap
1240     if (_oop_map_cache == NULL) {
1241       // Release stores from OopMapCache constructor before assignment
1242       // to _oop_map_cache. C++ compilers on ppc do not emit the
1243       // required memory barrier only because of the volatile
1244       // qualifier of _oop_map_cache.
1245       OrderAccess::release_store_ptr(&_oop_map_cache, new OopMapCache());
1246     }
1247   }
1248   // _oop_map_cache is constant after init; lookup below does is own locking.
1249   _oop_map_cache->lookup(method, bci, entry_for);
1250 }
1251 
1252 
1253 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1254   for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1255     Symbol* f_name = fs.name();
1256     Symbol* f_sig  = fs.signature();
1257     if (f_name == name && f_sig == sig) {
1258       fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1259       return true;
1260     }
1261   }
1262   return false;
1263 }
1264 
1265 
1266 Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1267   const int n = local_interfaces()->length();
1268   for (int i = 0; i < n; i++) {
1269     Klass* intf1 = local_interfaces()->at(i);
1270     assert(intf1->is_interface(), "just checking type");
1271     // search for field in current interface
1272     if (InstanceKlass::cast(intf1)->find_local_field(name, sig, fd)) {
1273       assert(fd->is_static(), "interface field must be static");
1274       return intf1;
1275     }
1276     // search for field in direct superinterfaces
1277     Klass* intf2 = InstanceKlass::cast(intf1)->find_interface_field(name, sig, fd);
1278     if (intf2 != NULL) return intf2;
1279   }
1280   // otherwise field lookup fails
1281   return NULL;
1282 }
1283 
1284 
1285 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1286   // search order according to newest JVM spec (5.4.3.2, p.167).
1287   // 1) search for field in current klass
1288   if (find_local_field(name, sig, fd)) {
1289     return const_cast<InstanceKlass*>(this);
1290   }
1291   // 2) search for field recursively in direct superinterfaces
1292   { Klass* intf = find_interface_field(name, sig, fd);
1293     if (intf != NULL) return intf;
1294   }
1295   // 3) apply field lookup recursively if superclass exists
1296   { Klass* supr = super();
1297     if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, fd);
1298   }
1299   // 4) otherwise field lookup fails
1300   return NULL;
1301 }
1302 
1303 
1304 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const {
1305   // search order according to newest JVM spec (5.4.3.2, p.167).
1306   // 1) search for field in current klass
1307   if (find_local_field(name, sig, fd)) {
1308     if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this);
1309   }
1310   // 2) search for field recursively in direct superinterfaces
1311   if (is_static) {
1312     Klass* intf = find_interface_field(name, sig, fd);
1313     if (intf != NULL) return intf;
1314   }
1315   // 3) apply field lookup recursively if superclass exists
1316   { Klass* supr = super();
1317     if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, is_static, fd);
1318   }
1319   // 4) otherwise field lookup fails
1320   return NULL;
1321 }
1322 
1323 
1324 bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1325   for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1326     if (fs.offset() == offset) {
1327       fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1328       if (fd->is_static() == is_static) return true;
1329     }
1330   }
1331   return false;
1332 }
1333 
1334 
1335 bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1336   Klass* klass = const_cast<InstanceKlass*>(this);
1337   while (klass != NULL) {
1338     if (InstanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) {
1339       return true;
1340     }
1341     klass = klass->super();
1342   }
1343   return false;
1344 }
1345 
1346 
1347 void InstanceKlass::methods_do(void f(Method* method)) {
1348   // Methods aren't stable until they are loaded.  This can be read outside
1349   // a lock through the ClassLoaderData for profiling
1350   if (!is_loaded()) {
1351     return;
1352   }
1353 
1354   int len = methods()->length();
1355   for (int index = 0; index < len; index++) {
1356     Method* m = methods()->at(index);
1357     assert(m->is_method(), "must be method");
1358     f(m);
1359   }
1360 }
1361 
1362 
1363 void InstanceKlass::do_local_static_fields(FieldClosure* cl) {
1364   for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1365     if (fs.access_flags().is_static()) {
1366       fieldDescriptor& fd = fs.field_descriptor();
1367       cl->do_field(&fd);
1368     }
1369   }
1370 }
1371 
1372 
1373 void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle mirror, TRAPS) {
1374   instanceKlassHandle h_this(THREAD, this);
1375   do_local_static_fields_impl(h_this, f, mirror, CHECK);
1376 }
1377 
1378 
1379 void InstanceKlass::do_local_static_fields_impl(instanceKlassHandle this_k,
1380                              void f(fieldDescriptor* fd, Handle, TRAPS), Handle mirror, TRAPS) {
1381   for (JavaFieldStream fs(this_k()); !fs.done(); fs.next()) {
1382     if (fs.access_flags().is_static()) {
1383       fieldDescriptor& fd = fs.field_descriptor();
1384       f(&fd, mirror, CHECK);
1385     }
1386   }
1387 }
1388 
1389 
1390 static int compare_fields_by_offset(int* a, int* b) {
1391   return a[0] - b[0];
1392 }
1393 
1394 void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) {
1395   InstanceKlass* super = superklass();
1396   if (super != NULL) {
1397     super->do_nonstatic_fields(cl);
1398   }
1399   fieldDescriptor fd;
1400   int length = java_fields_count();
1401   // In DebugInfo nonstatic fields are sorted by offset.
1402   int* fields_sorted = NEW_C_HEAP_ARRAY(int, 2*(length+1), mtClass);
1403   int j = 0;
1404   for (int i = 0; i < length; i += 1) {
1405     fd.reinitialize(this, i);
1406     if (!fd.is_static()) {
1407       fields_sorted[j + 0] = fd.offset();
1408       fields_sorted[j + 1] = i;
1409       j += 2;
1410     }
1411   }
1412   if (j > 0) {
1413     length = j;
1414     // _sort_Fn is defined in growableArray.hpp.
1415     qsort(fields_sorted, length/2, 2*sizeof(int), (_sort_Fn)compare_fields_by_offset);
1416     for (int i = 0; i < length; i += 2) {
1417       fd.reinitialize(this, fields_sorted[i + 1]);
1418       assert(!fd.is_static() && fd.offset() == fields_sorted[i], "only nonstatic fields");
1419       cl->do_field(&fd);
1420     }
1421   }
1422   FREE_C_HEAP_ARRAY(int, fields_sorted);
1423 }
1424 
1425 
1426 void InstanceKlass::array_klasses_do(void f(Klass* k, TRAPS), TRAPS) {
1427   if (array_klasses() != NULL)
1428     ArrayKlass::cast(array_klasses())->array_klasses_do(f, THREAD);
1429 }
1430 
1431 void InstanceKlass::array_klasses_do(void f(Klass* k)) {
1432   if (array_klasses() != NULL)
1433     ArrayKlass::cast(array_klasses())->array_klasses_do(f);
1434 }
1435 
1436 #ifdef ASSERT
1437 static int linear_search(const Array<Method*>* methods,
1438                          const Symbol* name,
1439                          const Symbol* signature) {
1440   const int len = methods->length();
1441   for (int index = 0; index < len; index++) {
1442     const Method* const m = methods->at(index);
1443     assert(m->is_method(), "must be method");
1444     if (m->signature() == signature && m->name() == name) {
1445        return index;
1446     }
1447   }
1448   return -1;
1449 }
1450 #endif
1451 
1452 static int binary_search(const Array<Method*>* methods, const Symbol* name) {
1453   int len = methods->length();
1454   // methods are sorted, so do binary search
1455   int l = 0;
1456   int h = len - 1;
1457   while (l <= h) {
1458     int mid = (l + h) >> 1;
1459     Method* m = methods->at(mid);
1460     assert(m->is_method(), "must be method");
1461     int res = m->name()->fast_compare(name);
1462     if (res == 0) {
1463       return mid;
1464     } else if (res < 0) {
1465       l = mid + 1;
1466     } else {
1467       h = mid - 1;
1468     }
1469   }
1470   return -1;
1471 }
1472 
1473 // find_method looks up the name/signature in the local methods array
1474 Method* InstanceKlass::find_method(const Symbol* name,
1475                                    const Symbol* signature) const {
1476   return find_method_impl(name, signature, find_overpass, find_static, find_private);
1477 }
1478 
1479 Method* InstanceKlass::find_method_impl(const Symbol* name,
1480                                         const Symbol* signature,
1481                                         OverpassLookupMode overpass_mode,
1482                                         StaticLookupMode static_mode,
1483                                         PrivateLookupMode private_mode) const {
1484   return InstanceKlass::find_method_impl(methods(),
1485                                          name,
1486                                          signature,
1487                                          overpass_mode,
1488                                          static_mode,
1489                                          private_mode);
1490 }
1491 
1492 // find_instance_method looks up the name/signature in the local methods array
1493 // and skips over static methods
1494 Method* InstanceKlass::find_instance_method(const Array<Method*>* methods,
1495                                             const Symbol* name,
1496                                             const Symbol* signature) {
1497   Method* const meth = InstanceKlass::find_method_impl(methods,
1498                                                  name,
1499                                                  signature,
1500                                                  find_overpass,
1501                                                  skip_static,
1502                                                  find_private);
1503   assert(((meth == NULL) || !meth->is_static()),
1504     "find_instance_method should have skipped statics");
1505   return meth;
1506 }
1507 
1508 // find_instance_method looks up the name/signature in the local methods array
1509 // and skips over static methods
1510 Method* InstanceKlass::find_instance_method(const Symbol* name, const Symbol* signature) const {
1511   return InstanceKlass::find_instance_method(methods(), name, signature);
1512 }
1513 
1514 // Find looks up the name/signature in the local methods array
1515 // and filters on the overpass, static and private flags
1516 // This returns the first one found
1517 // note that the local methods array can have up to one overpass, one static
1518 // and one instance (private or not) with the same name/signature
1519 Method* InstanceKlass::find_local_method(const Symbol* name,
1520                                          const Symbol* signature,
1521                                          OverpassLookupMode overpass_mode,
1522                                          StaticLookupMode static_mode,
1523                                          PrivateLookupMode private_mode) const {
1524   return InstanceKlass::find_method_impl(methods(),
1525                                          name,
1526                                          signature,
1527                                          overpass_mode,
1528                                          static_mode,
1529                                          private_mode);
1530 }
1531 
1532 // Find looks up the name/signature in the local methods array
1533 // and filters on the overpass, static and private flags
1534 // This returns the first one found
1535 // note that the local methods array can have up to one overpass, one static
1536 // and one instance (private or not) with the same name/signature
1537 Method* InstanceKlass::find_local_method(const Array<Method*>* methods,
1538                                          const Symbol* name,
1539                                          const Symbol* signature,
1540                                          OverpassLookupMode overpass_mode,
1541                                          StaticLookupMode static_mode,
1542                                          PrivateLookupMode private_mode) {
1543   return InstanceKlass::find_method_impl(methods,
1544                                          name,
1545                                          signature,
1546                                          overpass_mode,
1547                                          static_mode,
1548                                          private_mode);
1549 }
1550 
1551 Method* InstanceKlass::find_method(const Array<Method*>* methods,
1552                                    const Symbol* name,
1553                                    const Symbol* signature) {
1554   return InstanceKlass::find_method_impl(methods,
1555                                          name,
1556                                          signature,
1557                                          find_overpass,
1558                                          find_static,
1559                                          find_private);
1560 }
1561 
1562 Method* InstanceKlass::find_method_impl(const Array<Method*>* methods,
1563                                         const Symbol* name,
1564                                         const Symbol* signature,
1565                                         OverpassLookupMode overpass_mode,
1566                                         StaticLookupMode static_mode,
1567                                         PrivateLookupMode private_mode) {
1568   int hit = find_method_index(methods, name, signature, overpass_mode, static_mode, private_mode);
1569   return hit >= 0 ? methods->at(hit): NULL;
1570 }
1571 
1572 // true if method matches signature and conforms to skipping_X conditions.
1573 static bool method_matches(const Method* m,
1574                            const Symbol* signature,
1575                            bool skipping_overpass,
1576                            bool skipping_static,
1577                            bool skipping_private) {
1578   return ((m->signature() == signature) &&
1579     (!skipping_overpass || !m->is_overpass()) &&
1580     (!skipping_static || !m->is_static()) &&
1581     (!skipping_private || !m->is_private()));
1582 }
1583 
1584 // Used directly for default_methods to find the index into the
1585 // default_vtable_indices, and indirectly by find_method
1586 // find_method_index looks in the local methods array to return the index
1587 // of the matching name/signature. If, overpass methods are being ignored,
1588 // the search continues to find a potential non-overpass match.  This capability
1589 // is important during method resolution to prefer a static method, for example,
1590 // over an overpass method.
1591 // There is the possibility in any _method's array to have the same name/signature
1592 // for a static method, an overpass method and a local instance method
1593 // To correctly catch a given method, the search criteria may need
1594 // to explicitly skip the other two. For local instance methods, it
1595 // is often necessary to skip private methods
1596 int InstanceKlass::find_method_index(const Array<Method*>* methods,
1597                                      const Symbol* name,
1598                                      const Symbol* signature,
1599                                      OverpassLookupMode overpass_mode,
1600                                      StaticLookupMode static_mode,
1601                                      PrivateLookupMode private_mode) {
1602   const bool skipping_overpass = (overpass_mode == skip_overpass);
1603   const bool skipping_static = (static_mode == skip_static);
1604   const bool skipping_private = (private_mode == skip_private);
1605   const int hit = binary_search(methods, name);
1606   if (hit != -1) {
1607     const Method* const m = methods->at(hit);
1608 
1609     // Do linear search to find matching signature.  First, quick check
1610     // for common case, ignoring overpasses if requested.
1611     if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1612           return hit;
1613     }
1614 
1615     // search downwards through overloaded methods
1616     int i;
1617     for (i = hit - 1; i >= 0; --i) {
1618         const Method* const m = methods->at(i);
1619         assert(m->is_method(), "must be method");
1620         if (m->name() != name) {
1621           break;
1622         }
1623         if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1624           return i;
1625         }
1626     }
1627     // search upwards
1628     for (i = hit + 1; i < methods->length(); ++i) {
1629         const Method* const m = methods->at(i);
1630         assert(m->is_method(), "must be method");
1631         if (m->name() != name) {
1632           break;
1633         }
1634         if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1635           return i;
1636         }
1637     }
1638     // not found
1639 #ifdef ASSERT
1640     const int index = (skipping_overpass || skipping_static || skipping_private) ? -1 :
1641       linear_search(methods, name, signature);
1642     assert(-1 == index, "binary search should have found entry %d", index);
1643 #endif
1644   }
1645   return -1;
1646 }
1647 
1648 int InstanceKlass::find_method_by_name(const Symbol* name, int* end) const {
1649   return find_method_by_name(methods(), name, end);
1650 }
1651 
1652 int InstanceKlass::find_method_by_name(const Array<Method*>* methods,
1653                                        const Symbol* name,
1654                                        int* end_ptr) {
1655   assert(end_ptr != NULL, "just checking");
1656   int start = binary_search(methods, name);
1657   int end = start + 1;
1658   if (start != -1) {
1659     while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start;
1660     while (end < methods->length() && (methods->at(end))->name() == name) ++end;
1661     *end_ptr = end;
1662     return start;
1663   }
1664   return -1;
1665 }
1666 
1667 // uncached_lookup_method searches both the local class methods array and all
1668 // superclasses methods arrays, skipping any overpass methods in superclasses.
1669 Method* InstanceKlass::uncached_lookup_method(const Symbol* name,
1670                                               const Symbol* signature,
1671                                               OverpassLookupMode overpass_mode) const {
1672   OverpassLookupMode overpass_local_mode = overpass_mode;
1673   const Klass* klass = this;
1674   while (klass != NULL) {
1675     Method* const method = InstanceKlass::cast(klass)->find_method_impl(name,
1676                                                                         signature,
1677                                                                         overpass_local_mode,
1678                                                                         find_static,
1679                                                                         find_private);
1680     if (method != NULL) {
1681       return method;
1682     }
1683     klass = klass->super();
1684     overpass_local_mode = skip_overpass;   // Always ignore overpass methods in superclasses
1685   }
1686   return NULL;
1687 }
1688 
1689 #ifdef ASSERT
1690 // search through class hierarchy and return true if this class or
1691 // one of the superclasses was redefined
1692 bool InstanceKlass::has_redefined_this_or_super() const {
1693   const Klass* klass = this;
1694   while (klass != NULL) {
1695     if (InstanceKlass::cast(klass)->has_been_redefined()) {
1696       return true;
1697     }
1698     klass = klass->super();
1699   }
1700   return false;
1701 }
1702 #endif
1703 
1704 // lookup a method in the default methods list then in all transitive interfaces
1705 // Do NOT return private or static methods
1706 Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name,
1707                                                          Symbol* signature) const {
1708   Method* m = NULL;
1709   if (default_methods() != NULL) {
1710     m = find_method(default_methods(), name, signature);
1711   }
1712   // Look up interfaces
1713   if (m == NULL) {
1714     m = lookup_method_in_all_interfaces(name, signature, find_defaults);
1715   }
1716   return m;
1717 }
1718 
1719 // lookup a method in all the interfaces that this class implements
1720 // Do NOT return private or static methods, new in JDK8 which are not externally visible
1721 // They should only be found in the initial InterfaceMethodRef
1722 Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name,
1723                                                        Symbol* signature,
1724                                                        DefaultsLookupMode defaults_mode) const {
1725   Array<Klass*>* all_ifs = transitive_interfaces();
1726   int num_ifs = all_ifs->length();
1727   InstanceKlass *ik = NULL;
1728   for (int i = 0; i < num_ifs; i++) {
1729     ik = InstanceKlass::cast(all_ifs->at(i));
1730     Method* m = ik->lookup_method(name, signature);
1731     if (m != NULL && m->is_public() && !m->is_static() &&
1732         ((defaults_mode != skip_defaults) || !m->is_default_method())) {
1733       return m;
1734     }
1735   }
1736   return NULL;
1737 }
1738 
1739 /* jni_id_for_impl for jfieldIds only */
1740 JNIid* InstanceKlass::jni_id_for_impl(instanceKlassHandle this_k, int offset) {
1741   MutexLocker ml(JfieldIdCreation_lock);
1742   // Retry lookup after we got the lock
1743   JNIid* probe = this_k->jni_ids() == NULL ? NULL : this_k->jni_ids()->find(offset);
1744   if (probe == NULL) {
1745     // Slow case, allocate new static field identifier
1746     probe = new JNIid(this_k(), offset, this_k->jni_ids());
1747     this_k->set_jni_ids(probe);
1748   }
1749   return probe;
1750 }
1751 
1752 
1753 /* jni_id_for for jfieldIds only */
1754 JNIid* InstanceKlass::jni_id_for(int offset) {
1755   JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset);
1756   if (probe == NULL) {
1757     probe = jni_id_for_impl(this, offset);
1758   }
1759   return probe;
1760 }
1761 
1762 u2 InstanceKlass::enclosing_method_data(int offset) const {
1763   const Array<jushort>* const inner_class_list = inner_classes();
1764   if (inner_class_list == NULL) {
1765     return 0;
1766   }
1767   const int length = inner_class_list->length();
1768   if (length % inner_class_next_offset == 0) {
1769     return 0;
1770   }
1771   const int index = length - enclosing_method_attribute_size;
1772   assert(offset < enclosing_method_attribute_size, "invalid offset");
1773   return inner_class_list->at(index + offset);
1774 }
1775 
1776 void InstanceKlass::set_enclosing_method_indices(u2 class_index,
1777                                                  u2 method_index) {
1778   Array<jushort>* inner_class_list = inner_classes();
1779   assert (inner_class_list != NULL, "_inner_classes list is not set up");
1780   int length = inner_class_list->length();
1781   if (length % inner_class_next_offset == enclosing_method_attribute_size) {
1782     int index = length - enclosing_method_attribute_size;
1783     inner_class_list->at_put(
1784       index + enclosing_method_class_index_offset, class_index);
1785     inner_class_list->at_put(
1786       index + enclosing_method_method_index_offset, method_index);
1787   }
1788 }
1789 
1790 // Lookup or create a jmethodID.
1791 // This code is called by the VMThread and JavaThreads so the
1792 // locking has to be done very carefully to avoid deadlocks
1793 // and/or other cache consistency problems.
1794 //
1795 jmethodID InstanceKlass::get_jmethod_id(instanceKlassHandle ik_h, const methodHandle& method_h) {
1796   size_t idnum = (size_t)method_h->method_idnum();
1797   jmethodID* jmeths = ik_h->methods_jmethod_ids_acquire();
1798   size_t length = 0;
1799   jmethodID id = NULL;
1800 
1801   // We use a double-check locking idiom here because this cache is
1802   // performance sensitive. In the normal system, this cache only
1803   // transitions from NULL to non-NULL which is safe because we use
1804   // release_set_methods_jmethod_ids() to advertise the new cache.
1805   // A partially constructed cache should never be seen by a racing
1806   // thread. We also use release_store_ptr() to save a new jmethodID
1807   // in the cache so a partially constructed jmethodID should never be
1808   // seen either. Cache reads of existing jmethodIDs proceed without a
1809   // lock, but cache writes of a new jmethodID requires uniqueness and
1810   // creation of the cache itself requires no leaks so a lock is
1811   // generally acquired in those two cases.
1812   //
1813   // If the RedefineClasses() API has been used, then this cache can
1814   // grow and we'll have transitions from non-NULL to bigger non-NULL.
1815   // Cache creation requires no leaks and we require safety between all
1816   // cache accesses and freeing of the old cache so a lock is generally
1817   // acquired when the RedefineClasses() API has been used.
1818 
1819   if (jmeths != NULL) {
1820     // the cache already exists
1821     if (!ik_h->idnum_can_increment()) {
1822       // the cache can't grow so we can just get the current values
1823       get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1824     } else {
1825       // cache can grow so we have to be more careful
1826       if (Threads::number_of_threads() == 0 ||
1827           SafepointSynchronize::is_at_safepoint()) {
1828         // we're single threaded or at a safepoint - no locking needed
1829         get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1830       } else {
1831         MutexLocker ml(JmethodIdCreation_lock);
1832         get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1833       }
1834     }
1835   }
1836   // implied else:
1837   // we need to allocate a cache so default length and id values are good
1838 
1839   if (jmeths == NULL ||   // no cache yet
1840       length <= idnum ||  // cache is too short
1841       id == NULL) {       // cache doesn't contain entry
1842 
1843     // This function can be called by the VMThread so we have to do all
1844     // things that might block on a safepoint before grabbing the lock.
1845     // Otherwise, we can deadlock with the VMThread or have a cache
1846     // consistency issue. These vars keep track of what we might have
1847     // to free after the lock is dropped.
1848     jmethodID  to_dealloc_id     = NULL;
1849     jmethodID* to_dealloc_jmeths = NULL;
1850 
1851     // may not allocate new_jmeths or use it if we allocate it
1852     jmethodID* new_jmeths = NULL;
1853     if (length <= idnum) {
1854       // allocate a new cache that might be used
1855       size_t size = MAX2(idnum+1, (size_t)ik_h->idnum_allocated_count());
1856       new_jmeths = NEW_C_HEAP_ARRAY(jmethodID, size+1, mtClass);
1857       memset(new_jmeths, 0, (size+1)*sizeof(jmethodID));
1858       // cache size is stored in element[0], other elements offset by one
1859       new_jmeths[0] = (jmethodID)size;
1860     }
1861 
1862     // allocate a new jmethodID that might be used
1863     jmethodID new_id = NULL;
1864     if (method_h->is_old() && !method_h->is_obsolete()) {
1865       // The method passed in is old (but not obsolete), we need to use the current version
1866       Method* current_method = ik_h->method_with_idnum((int)idnum);
1867       assert(current_method != NULL, "old and but not obsolete, so should exist");
1868       new_id = Method::make_jmethod_id(ik_h->class_loader_data(), current_method);
1869     } else {
1870       // It is the current version of the method or an obsolete method,
1871       // use the version passed in
1872       new_id = Method::make_jmethod_id(ik_h->class_loader_data(), method_h());
1873     }
1874 
1875     if (Threads::number_of_threads() == 0 ||
1876         SafepointSynchronize::is_at_safepoint()) {
1877       // we're single threaded or at a safepoint - no locking needed
1878       id = get_jmethod_id_fetch_or_update(ik_h, idnum, new_id, new_jmeths,
1879                                           &to_dealloc_id, &to_dealloc_jmeths);
1880     } else {
1881       MutexLocker ml(JmethodIdCreation_lock);
1882       id = get_jmethod_id_fetch_or_update(ik_h, idnum, new_id, new_jmeths,
1883                                           &to_dealloc_id, &to_dealloc_jmeths);
1884     }
1885 
1886     // The lock has been dropped so we can free resources.
1887     // Free up either the old cache or the new cache if we allocated one.
1888     if (to_dealloc_jmeths != NULL) {
1889       FreeHeap(to_dealloc_jmeths);
1890     }
1891     // free up the new ID since it wasn't needed
1892     if (to_dealloc_id != NULL) {
1893       Method::destroy_jmethod_id(ik_h->class_loader_data(), to_dealloc_id);
1894     }
1895   }
1896   return id;
1897 }
1898 
1899 // Figure out how many jmethodIDs haven't been allocated, and make
1900 // sure space for them is pre-allocated.  This makes getting all
1901 // method ids much, much faster with classes with more than 8
1902 // methods, and has a *substantial* effect on performance with jvmti
1903 // code that loads all jmethodIDs for all classes.
1904 void InstanceKlass::ensure_space_for_methodids(int start_offset) {
1905   int new_jmeths = 0;
1906   int length = methods()->length();
1907   for (int index = start_offset; index < length; index++) {
1908     Method* m = methods()->at(index);
1909     jmethodID id = m->find_jmethod_id_or_null();
1910     if (id == NULL) {
1911       new_jmeths++;
1912     }
1913   }
1914   if (new_jmeths != 0) {
1915     Method::ensure_jmethod_ids(class_loader_data(), new_jmeths);
1916   }
1917 }
1918 
1919 // Common code to fetch the jmethodID from the cache or update the
1920 // cache with the new jmethodID. This function should never do anything
1921 // that causes the caller to go to a safepoint or we can deadlock with
1922 // the VMThread or have cache consistency issues.
1923 //
1924 jmethodID InstanceKlass::get_jmethod_id_fetch_or_update(
1925             instanceKlassHandle ik_h, size_t idnum, jmethodID new_id,
1926             jmethodID* new_jmeths, jmethodID* to_dealloc_id_p,
1927             jmethodID** to_dealloc_jmeths_p) {
1928   assert(new_id != NULL, "sanity check");
1929   assert(to_dealloc_id_p != NULL, "sanity check");
1930   assert(to_dealloc_jmeths_p != NULL, "sanity check");
1931   assert(Threads::number_of_threads() == 0 ||
1932          SafepointSynchronize::is_at_safepoint() ||
1933          JmethodIdCreation_lock->owned_by_self(), "sanity check");
1934 
1935   // reacquire the cache - we are locked, single threaded or at a safepoint
1936   jmethodID* jmeths = ik_h->methods_jmethod_ids_acquire();
1937   jmethodID  id     = NULL;
1938   size_t     length = 0;
1939 
1940   if (jmeths == NULL ||                         // no cache yet
1941       (length = (size_t)jmeths[0]) <= idnum) {  // cache is too short
1942     if (jmeths != NULL) {
1943       // copy any existing entries from the old cache
1944       for (size_t index = 0; index < length; index++) {
1945         new_jmeths[index+1] = jmeths[index+1];
1946       }
1947       *to_dealloc_jmeths_p = jmeths;  // save old cache for later delete
1948     }
1949     ik_h->release_set_methods_jmethod_ids(jmeths = new_jmeths);
1950   } else {
1951     // fetch jmethodID (if any) from the existing cache
1952     id = jmeths[idnum+1];
1953     *to_dealloc_jmeths_p = new_jmeths;  // save new cache for later delete
1954   }
1955   if (id == NULL) {
1956     // No matching jmethodID in the existing cache or we have a new
1957     // cache or we just grew the cache. This cache write is done here
1958     // by the first thread to win the foot race because a jmethodID
1959     // needs to be unique once it is generally available.
1960     id = new_id;
1961 
1962     // The jmethodID cache can be read while unlocked so we have to
1963     // make sure the new jmethodID is complete before installing it
1964     // in the cache.
1965     OrderAccess::release_store_ptr(&jmeths[idnum+1], id);
1966   } else {
1967     *to_dealloc_id_p = new_id; // save new id for later delete
1968   }
1969   return id;
1970 }
1971 
1972 
1973 // Common code to get the jmethodID cache length and the jmethodID
1974 // value at index idnum if there is one.
1975 //
1976 void InstanceKlass::get_jmethod_id_length_value(jmethodID* cache,
1977        size_t idnum, size_t *length_p, jmethodID* id_p) {
1978   assert(cache != NULL, "sanity check");
1979   assert(length_p != NULL, "sanity check");
1980   assert(id_p != NULL, "sanity check");
1981 
1982   // cache size is stored in element[0], other elements offset by one
1983   *length_p = (size_t)cache[0];
1984   if (*length_p <= idnum) {  // cache is too short
1985     *id_p = NULL;
1986   } else {
1987     *id_p = cache[idnum+1];  // fetch jmethodID (if any)
1988   }
1989 }
1990 
1991 
1992 // Lookup a jmethodID, NULL if not found.  Do no blocking, no allocations, no handles
1993 jmethodID InstanceKlass::jmethod_id_or_null(Method* method) {
1994   size_t idnum = (size_t)method->method_idnum();
1995   jmethodID* jmeths = methods_jmethod_ids_acquire();
1996   size_t length;                                // length assigned as debugging crumb
1997   jmethodID id = NULL;
1998   if (jmeths != NULL &&                         // If there is a cache
1999       (length = (size_t)jmeths[0]) > idnum) {   // and if it is long enough,
2000     id = jmeths[idnum+1];                       // Look up the id (may be NULL)
2001   }
2002   return id;
2003 }
2004 
2005 inline DependencyContext InstanceKlass::dependencies() {
2006   DependencyContext dep_context(&_dep_context);
2007   return dep_context;
2008 }
2009 
2010 int InstanceKlass::mark_dependent_nmethods(KlassDepChange& changes) {
2011   return dependencies().mark_dependent_nmethods(changes);
2012 }
2013 
2014 void InstanceKlass::add_dependent_nmethod(nmethod* nm) {
2015   dependencies().add_dependent_nmethod(nm);
2016 }
2017 
2018 void InstanceKlass::remove_dependent_nmethod(nmethod* nm, bool delete_immediately) {
2019   dependencies().remove_dependent_nmethod(nm, delete_immediately);
2020 }
2021 
2022 #ifndef PRODUCT
2023 void InstanceKlass::print_dependent_nmethods(bool verbose) {
2024   dependencies().print_dependent_nmethods(verbose);
2025 }
2026 
2027 bool InstanceKlass::is_dependent_nmethod(nmethod* nm) {
2028   return dependencies().is_dependent_nmethod(nm);
2029 }
2030 #endif //PRODUCT
2031 
2032 void InstanceKlass::clean_weak_instanceklass_links(BoolObjectClosure* is_alive) {
2033   clean_implementors_list(is_alive);
2034   clean_method_data(is_alive);
2035 
2036   // Since GC iterates InstanceKlasses sequentially, it is safe to remove stale entries here.
2037   DependencyContext dep_context(&_dep_context);
2038   dep_context.expunge_stale_entries();
2039 }
2040 
2041 void InstanceKlass::clean_implementors_list(BoolObjectClosure* is_alive) {
2042   assert(class_loader_data()->is_alive(is_alive), "this klass should be live");
2043   if (is_interface()) {
2044     if (ClassUnloading) {
2045       Klass* impl = implementor();
2046       if (impl != NULL) {
2047         if (!impl->is_loader_alive(is_alive)) {
2048           // remove this guy
2049           Klass** klass = adr_implementor();
2050           assert(klass != NULL, "null klass");
2051           if (klass != NULL) {
2052             *klass = NULL;
2053           }
2054         }
2055       }
2056     }
2057   }
2058 }
2059 
2060 void InstanceKlass::clean_method_data(BoolObjectClosure* is_alive) {
2061   for (int m = 0; m < methods()->length(); m++) {
2062     MethodData* mdo = methods()->at(m)->method_data();
2063     if (mdo != NULL) {
2064       mdo->clean_method_data(is_alive);
2065     }
2066   }
2067 }
2068 
2069 
2070 static void remove_unshareable_in_class(Klass* k) {
2071   // remove klass's unshareable info
2072   k->remove_unshareable_info();
2073 }
2074 
2075 void InstanceKlass::remove_unshareable_info() {
2076   Klass::remove_unshareable_info();
2077   // Unlink the class
2078   if (is_linked()) {
2079     unlink_class();
2080   }
2081   init_implementor();
2082 
2083   constants()->remove_unshareable_info();
2084 
2085   assert(_dep_context == DependencyContext::EMPTY, "dependency context is not shareable");
2086 
2087   for (int i = 0; i < methods()->length(); i++) {
2088     Method* m = methods()->at(i);
2089     m->remove_unshareable_info();
2090   }
2091 
2092   // do array classes also.
2093   array_klasses_do(remove_unshareable_in_class);
2094 }
2095 
2096 static void restore_unshareable_in_class(Klass* k, TRAPS) {
2097   // Array classes have null protection domain.
2098   // --> see ArrayKlass::complete_create_array_klass()
2099   k->restore_unshareable_info(ClassLoaderData::the_null_class_loader_data(), Handle(), CHECK);
2100 }
2101 
2102 void InstanceKlass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain, TRAPS) {
2103   Klass::restore_unshareable_info(loader_data, protection_domain, CHECK);
2104   instanceKlassHandle ik(THREAD, this);
2105 
2106   Array<Method*>* methods = ik->methods();
2107   int num_methods = methods->length();
2108   for (int index2 = 0; index2 < num_methods; ++index2) {
2109     methodHandle m(THREAD, methods->at(index2));
2110     m->restore_unshareable_info(CHECK);
2111   }
2112   if (JvmtiExport::has_redefined_a_class()) {
2113     // Reinitialize vtable because RedefineClasses may have changed some
2114     // entries in this vtable for super classes so the CDS vtable might
2115     // point to old or obsolete entries.  RedefineClasses doesn't fix up
2116     // vtables in the shared system dictionary, only the main one.
2117     // It also redefines the itable too so fix that too.
2118     ResourceMark rm(THREAD);
2119     ik->vtable()->initialize_vtable(false, CHECK);
2120     ik->itable()->initialize_itable(false, CHECK);
2121   }
2122 
2123   // restore constant pool resolved references
2124   ik->constants()->restore_unshareable_info(CHECK);
2125 
2126   ik->array_klasses_do(restore_unshareable_in_class, CHECK);
2127 }
2128 
2129 // returns true IFF is_in_error_state() has been changed as a result of this call.
2130 bool InstanceKlass::check_sharing_error_state() {
2131   assert(DumpSharedSpaces, "should only be called during dumping");
2132   bool old_state = is_in_error_state();
2133 
2134   if (!is_in_error_state()) {
2135     bool bad = false;
2136     for (InstanceKlass* sup = java_super(); sup; sup = sup->java_super()) {
2137       if (sup->is_in_error_state()) {
2138         bad = true;
2139         break;
2140       }
2141     }
2142     if (!bad) {
2143       Array<Klass*>* interfaces = transitive_interfaces();
2144       for (int i = 0; i < interfaces->length(); i++) {
2145         Klass* iface = interfaces->at(i);
2146         if (InstanceKlass::cast(iface)->is_in_error_state()) {
2147           bad = true;
2148           break;
2149         }
2150       }
2151     }
2152 
2153     if (bad) {
2154       set_in_error_state();
2155     }
2156   }
2157 
2158   return (old_state != is_in_error_state());
2159 }
2160 
2161 static void clear_all_breakpoints(Method* m) {
2162   m->clear_all_breakpoints();
2163 }
2164 
2165 
2166 void InstanceKlass::notify_unload_class(InstanceKlass* ik) {
2167   // notify the debugger
2168   if (JvmtiExport::should_post_class_unload()) {
2169     JvmtiExport::post_class_unload(ik);
2170   }
2171 
2172   // notify ClassLoadingService of class unload
2173   ClassLoadingService::notify_class_unloaded(ik);
2174 }
2175 
2176 void InstanceKlass::release_C_heap_structures(InstanceKlass* ik) {
2177   // Clean up C heap
2178   ik->release_C_heap_structures();
2179   ik->constants()->release_C_heap_structures();
2180 }
2181 
2182 void InstanceKlass::release_C_heap_structures() {
2183 
2184   // Can't release the constant pool here because the constant pool can be
2185   // deallocated separately from the InstanceKlass for default methods and
2186   // redefine classes.
2187 
2188   // Deallocate oop map cache
2189   if (_oop_map_cache != NULL) {
2190     delete _oop_map_cache;
2191     _oop_map_cache = NULL;
2192   }
2193 
2194   // Deallocate JNI identifiers for jfieldIDs
2195   JNIid::deallocate(jni_ids());
2196   set_jni_ids(NULL);
2197 
2198   jmethodID* jmeths = methods_jmethod_ids_acquire();
2199   if (jmeths != (jmethodID*)NULL) {
2200     release_set_methods_jmethod_ids(NULL);
2201     FreeHeap(jmeths);
2202   }
2203 
2204   // Deallocate MemberNameTable
2205   {
2206     Mutex* lock_or_null = SafepointSynchronize::is_at_safepoint() ? NULL : MemberNameTable_lock;
2207     MutexLockerEx ml(lock_or_null, Mutex::_no_safepoint_check_flag);
2208     MemberNameTable* mnt = member_names();
2209     if (mnt != NULL) {
2210       delete mnt;
2211       set_member_names(NULL);
2212     }
2213   }
2214 
2215   // Release dependencies.
2216   // It is desirable to use DC::remove_all_dependents() here, but, unfortunately,
2217   // it is not safe (see JDK-8143408). The problem is that the klass dependency
2218   // context can contain live dependencies, since there's a race between nmethod &
2219   // klass unloading. If the klass is dead when nmethod unloading happens, relevant
2220   // dependencies aren't removed from the context associated with the class (see
2221   // nmethod::flush_dependencies). It ends up during klass unloading as seemingly
2222   // live dependencies pointing to unloaded nmethods and causes a crash in
2223   // DC::remove_all_dependents() when it touches unloaded nmethod.
2224   dependencies().wipe();
2225 
2226   // Deallocate breakpoint records
2227   if (breakpoints() != 0x0) {
2228     methods_do(clear_all_breakpoints);
2229     assert(breakpoints() == 0x0, "should have cleared breakpoints");
2230   }
2231 
2232   // deallocate the cached class file
2233   if (_cached_class_file != NULL) {
2234     os::free(_cached_class_file);
2235     _cached_class_file = NULL;
2236   }
2237 
2238   // Decrement symbol reference counts associated with the unloaded class.
2239   if (_name != NULL) _name->decrement_refcount();
2240   // unreference array name derived from this class name (arrays of an unloaded
2241   // class can't be referenced anymore).
2242   if (_array_name != NULL)  _array_name->decrement_refcount();
2243   if (_source_debug_extension != NULL) FREE_C_HEAP_ARRAY(char, _source_debug_extension);
2244 
2245   assert(_total_instanceKlass_count >= 1, "Sanity check");
2246   Atomic::dec(&_total_instanceKlass_count);
2247 }
2248 
2249 void InstanceKlass::set_source_debug_extension(const char* array, int length) {
2250   if (array == NULL) {
2251     _source_debug_extension = NULL;
2252   } else {
2253     // Adding one to the attribute length in order to store a null terminator
2254     // character could cause an overflow because the attribute length is
2255     // already coded with an u4 in the classfile, but in practice, it's
2256     // unlikely to happen.
2257     assert((length+1) > length, "Overflow checking");
2258     char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass);
2259     for (int i = 0; i < length; i++) {
2260       sde[i] = array[i];
2261     }
2262     sde[length] = '\0';
2263     _source_debug_extension = sde;
2264   }
2265 }
2266 
2267 address InstanceKlass::static_field_addr(int offset) {
2268   return (address)(offset + InstanceMirrorKlass::offset_of_static_fields() + cast_from_oop<intptr_t>(java_mirror()));
2269 }
2270 
2271 
2272 const char* InstanceKlass::signature_name() const {
2273   int hash_len = 0;
2274   char hash_buf[40];
2275 
2276   // If this is an anonymous class, append a hash to make the name unique
2277   if (is_anonymous()) {
2278     intptr_t hash = (java_mirror() != NULL) ? java_mirror()->identity_hash() : 0;
2279     jio_snprintf(hash_buf, sizeof(hash_buf), "/" UINTX_FORMAT, (uintx)hash);
2280     hash_len = (int)strlen(hash_buf);
2281   }
2282 
2283   // Get the internal name as a c string
2284   const char* src = (const char*) (name()->as_C_string());
2285   const int src_length = (int)strlen(src);
2286 
2287   char* dest = NEW_RESOURCE_ARRAY(char, src_length + hash_len + 3);
2288 
2289   // Add L as type indicator
2290   int dest_index = 0;
2291   dest[dest_index++] = is_value_type_klass() ? 'Q' : 'L';
2292 
2293   // Add the actual class name
2294   for (int src_index = 0; src_index < src_length; ) {
2295     dest[dest_index++] = src[src_index++];
2296   }
2297 
2298   // If we have a hash, append it
2299   for (int hash_index = 0; hash_index < hash_len; ) {
2300     dest[dest_index++] = hash_buf[hash_index++];
2301   }
2302 
2303   // Add the semicolon and the NULL
2304   dest[dest_index++] = ';';
2305   dest[dest_index] = '\0';
2306   return dest;
2307 }
2308 
2309 // different verisons of is_same_class_package
2310 bool InstanceKlass::is_same_class_package(const Klass* class2) const {
2311   const Klass* const class1 = (const Klass* const)this;
2312   oop classloader1 = InstanceKlass::cast(class1)->class_loader();
2313   const Symbol* const classname1 = class1->name();
2314 
2315   if (class2->is_objArray_klass()) {
2316     class2 = ObjArrayKlass::cast(class2)->bottom_klass();
2317   }
2318   oop classloader2;
2319   if (class2->is_instance_klass()) {
2320     classloader2 = InstanceKlass::cast(class2)->class_loader();
2321   } else {
2322     assert(class2->is_typeArray_klass(), "should be type array");
2323     classloader2 = NULL;
2324   }
2325   const Symbol* classname2 = class2->name();
2326 
2327   return InstanceKlass::is_same_class_package(classloader1, classname1,
2328                                               classloader2, classname2);
2329 }
2330 
2331 bool InstanceKlass::is_same_class_package(oop other_class_loader,
2332                                           const Symbol* other_class_name) const {
2333   oop this_class_loader = class_loader();
2334   const Symbol* const this_class_name = name();
2335 
2336   return InstanceKlass::is_same_class_package(this_class_loader,
2337                                              this_class_name,
2338                                              other_class_loader,
2339                                              other_class_name);
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, const Symbol* class_name1,
2345                                           oop class_loader2, const 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' || *name1 != 'Q') {
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' || *name2 != 'Q') {
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(const InstanceKlass* class1,
2425                                                 const Klass* class2,
2426                                                 TRAPS) {
2427   if (class2 == class1) return true;
2428   if (!class2->is_instance_klass())  return false;
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   const InstanceKlass* 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     const 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 = InstanceKlass::cast(next);
2447   }
2448 
2449   // Now do the same for class2.
2450   const InstanceKlass* outer2 = InstanceKlass::cast(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 = InstanceKlass::cast(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 InstanceKlass* InstanceKlass::compute_enclosing_class_impl(const InstanceKlass* k,
2488                                                            bool* inner_is_member,
2489                                                            TRAPS) {
2490   InstanceKlass* outer_klass = NULL;
2491   *inner_is_member = false;
2492   int ooff = 0, noff = 0;
2493   if (find_inner_classes_attr(k, &ooff, &noff, THREAD)) {
2494     constantPoolHandle i_cp(THREAD, k->constants());
2495     if (ooff != 0) {
2496       Klass* ok = i_cp->klass_at(ooff, CHECK_NULL);
2497       outer_klass = InstanceKlass::cast(ok);
2498       *inner_is_member = true;
2499     }
2500     if (NULL == outer_klass) {
2501       // It may be anonymous; try for that.
2502       int encl_method_class_idx = k->enclosing_method_class_index();
2503       if (encl_method_class_idx != 0) {
2504         Klass* ok = i_cp->klass_at(encl_method_class_idx, CHECK_NULL);
2505         outer_klass = InstanceKlass::cast(ok);
2506         *inner_is_member = false;
2507       }
2508     }
2509   }
2510 
2511   // If no inner class attribute found for this class.
2512   if (NULL == outer_klass) return NULL;
2513 
2514   // Throws an exception if outer klass has not declared k as an inner klass
2515   // We need evidence that each klass knows about the other, or else
2516   // the system could allow a spoof of an inner class to gain access rights.
2517   Reflection::check_for_inner_class(outer_klass, k, *inner_is_member, CHECK_NULL);
2518   return outer_klass;
2519 }
2520 
2521 jint InstanceKlass::compute_modifier_flags(TRAPS) const {
2522   jint access = access_flags().as_int();
2523 
2524   // But check if it happens to be member class.
2525   instanceKlassHandle ik(THREAD, this);
2526   InnerClassesIterator iter(ik);
2527   for (; !iter.done(); iter.next()) {
2528     int ioff = iter.inner_class_info_index();
2529     // Inner class attribute can be zero, skip it.
2530     // Strange but true:  JVM spec. allows null inner class refs.
2531     if (ioff == 0) continue;
2532 
2533     // only look at classes that are already loaded
2534     // since we are looking for the flags for our self.
2535     Symbol* inner_name = ik->constants()->klass_name_at(ioff);
2536     if ((ik->name() == inner_name)) {
2537       // This is really a member class.
2538       access = iter.inner_access_flags();
2539       break;
2540     }
2541   }
2542   // Remember to strip ACC_SUPER bit
2543   return (access & (~JVM_ACC_SUPER)) & JVM_ACC_WRITTEN_FLAGS;
2544 }
2545 
2546 jint InstanceKlass::jvmti_class_status() const {
2547   jint result = 0;
2548 
2549   if (is_linked()) {
2550     result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED;
2551   }
2552 
2553   if (is_initialized()) {
2554     assert(is_linked(), "Class status is not consistent");
2555     result |= JVMTI_CLASS_STATUS_INITIALIZED;
2556   }
2557   if (is_in_error_state()) {
2558     result |= JVMTI_CLASS_STATUS_ERROR;
2559   }
2560   return result;
2561 }
2562 
2563 Method* InstanceKlass::method_at_itable(Klass* holder, int index, TRAPS) {
2564   itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2565   int method_table_offset_in_words = ioe->offset()/wordSize;
2566   int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words())
2567                        / itableOffsetEntry::size();
2568 
2569   for (int cnt = 0 ; ; cnt ++, ioe ++) {
2570     // If the interface isn't implemented by the receiver class,
2571     // the VM should throw IncompatibleClassChangeError.
2572     if (cnt >= nof_interfaces) {
2573       THROW_NULL(vmSymbols::java_lang_IncompatibleClassChangeError());
2574     }
2575 
2576     Klass* ik = ioe->interface_klass();
2577     if (ik == holder) break;
2578   }
2579 
2580   itableMethodEntry* ime = ioe->first_method_entry(this);
2581   Method* m = ime[index].method();
2582   if (m == NULL) {
2583     THROW_NULL(vmSymbols::java_lang_AbstractMethodError());
2584   }
2585   return m;
2586 }
2587 
2588 
2589 #if INCLUDE_JVMTI
2590 // update default_methods for redefineclasses for methods that are
2591 // not yet in the vtable due to concurrent subclass define and superinterface
2592 // redefinition
2593 // Note: those in the vtable, should have been updated via adjust_method_entries
2594 void InstanceKlass::adjust_default_methods(InstanceKlass* holder, bool* trace_name_printed) {
2595   // search the default_methods for uses of either obsolete or EMCP methods
2596   if (default_methods() != NULL) {
2597     for (int index = 0; index < default_methods()->length(); index ++) {
2598       Method* old_method = default_methods()->at(index);
2599       if (old_method == NULL || old_method->method_holder() != holder || !old_method->is_old()) {
2600         continue; // skip uninteresting entries
2601       }
2602       assert(!old_method->is_deleted(), "default methods may not be deleted");
2603 
2604       Method* new_method = holder->method_with_idnum(old_method->orig_method_idnum());
2605 
2606       assert(new_method != NULL, "method_with_idnum() should not be NULL");
2607       assert(old_method != new_method, "sanity check");
2608 
2609       default_methods()->at_put(index, new_method);
2610       if (RC_TRACE_IN_RANGE(0x00100000, 0x00400000)) {
2611         if (!(*trace_name_printed)) {
2612           // RC_TRACE_MESG macro has an embedded ResourceMark
2613           RC_TRACE_MESG(("adjust: klassname=%s default methods from name=%s",
2614                          external_name(),
2615                          old_method->method_holder()->external_name()));
2616           *trace_name_printed = true;
2617         }
2618         RC_TRACE(0x00100000, ("default method update: %s(%s) ",
2619                               new_method->name()->as_C_string(),
2620                               new_method->signature()->as_C_string()));
2621       }
2622     }
2623   }
2624 }
2625 #endif // INCLUDE_JVMTI
2626 
2627 // On-stack replacement stuff
2628 void InstanceKlass::add_osr_nmethod(nmethod* n) {
2629   // only one compilation can be active
2630   {
2631     // This is a short non-blocking critical region, so the no safepoint check is ok.
2632     MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2633     assert(n->is_osr_method(), "wrong kind of nmethod");
2634     n->set_osr_link(osr_nmethods_head());
2635     set_osr_nmethods_head(n);
2636     // Raise the highest osr level if necessary
2637     if (TieredCompilation) {
2638       Method* m = n->method();
2639       m->set_highest_osr_comp_level(MAX2(m->highest_osr_comp_level(), n->comp_level()));
2640     }
2641   }
2642 
2643   // Get rid of the osr methods for the same bci that have lower levels.
2644   if (TieredCompilation) {
2645     for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) {
2646       nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true);
2647       if (inv != NULL && inv->is_in_use()) {
2648         inv->make_not_entrant();
2649       }
2650     }
2651   }
2652 }
2653 
2654 
2655 void InstanceKlass::remove_osr_nmethod(nmethod* n) {
2656   // This is a short non-blocking critical region, so the no safepoint check is ok.
2657   MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2658   assert(n->is_osr_method(), "wrong kind of nmethod");
2659   nmethod* last = NULL;
2660   nmethod* cur  = osr_nmethods_head();
2661   int max_level = CompLevel_none;  // Find the max comp level excluding n
2662   Method* m = n->method();
2663   // Search for match
2664   while(cur != NULL && cur != n) {
2665     if (TieredCompilation && m == cur->method()) {
2666       // Find max level before n
2667       max_level = MAX2(max_level, cur->comp_level());
2668     }
2669     last = cur;
2670     cur = cur->osr_link();
2671   }
2672   nmethod* next = NULL;
2673   if (cur == n) {
2674     next = cur->osr_link();
2675     if (last == NULL) {
2676       // Remove first element
2677       set_osr_nmethods_head(next);
2678     } else {
2679       last->set_osr_link(next);
2680     }
2681   }
2682   n->set_osr_link(NULL);
2683   if (TieredCompilation) {
2684     cur = next;
2685     while (cur != NULL) {
2686       // Find max level after n
2687       if (m == cur->method()) {
2688         max_level = MAX2(max_level, cur->comp_level());
2689       }
2690       cur = cur->osr_link();
2691     }
2692     m->set_highest_osr_comp_level(max_level);
2693   }
2694 }
2695 
2696 int InstanceKlass::mark_osr_nmethods(const Method* m) {
2697   // This is a short non-blocking critical region, so the no safepoint check is ok.
2698   MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2699   nmethod* osr = osr_nmethods_head();
2700   int found = 0;
2701   while (osr != NULL) {
2702     assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
2703     if (osr->method() == m) {
2704       osr->mark_for_deoptimization();
2705       found++;
2706     }
2707     osr = osr->osr_link();
2708   }
2709   return found;
2710 }
2711 
2712 nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const {
2713   // This is a short non-blocking critical region, so the no safepoint check is ok.
2714   MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2715   nmethod* osr = osr_nmethods_head();
2716   nmethod* best = NULL;
2717   while (osr != NULL) {
2718     assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
2719     // There can be a time when a c1 osr method exists but we are waiting
2720     // for a c2 version. When c2 completes its osr nmethod we will trash
2721     // the c1 version and only be able to find the c2 version. However
2722     // while we overflow in the c1 code at back branches we don't want to
2723     // try and switch to the same code as we are already running
2724 
2725     if (osr->method() == m &&
2726         (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) {
2727       if (match_level) {
2728         if (osr->comp_level() == comp_level) {
2729           // Found a match - return it.
2730           return osr;
2731         }
2732       } else {
2733         if (best == NULL || (osr->comp_level() > best->comp_level())) {
2734           if (osr->comp_level() == CompLevel_highest_tier) {
2735             // Found the best possible - return it.
2736             return osr;
2737           }
2738           best = osr;
2739         }
2740       }
2741     }
2742     osr = osr->osr_link();
2743   }
2744   if (best != NULL && best->comp_level() >= comp_level && match_level == false) {
2745     return best;
2746   }
2747   return NULL;
2748 }
2749 
2750 bool InstanceKlass::add_member_name(Handle mem_name) {
2751   jweak mem_name_wref = JNIHandles::make_weak_global(mem_name);
2752   MutexLocker ml(MemberNameTable_lock);
2753   DEBUG_ONLY(NoSafepointVerifier nsv);
2754 
2755   // Check if method has been redefined while taking out MemberNameTable_lock, if so
2756   // return false.  We cannot cache obsolete methods. They will crash when the function
2757   // is called!
2758   Method* method = (Method*)java_lang_invoke_MemberName::vmtarget(mem_name());
2759   if (method->is_obsolete()) {
2760     return false;
2761   } else if (method->is_old()) {
2762     // Replace method with redefined version
2763     java_lang_invoke_MemberName::set_vmtarget(mem_name(), method_with_idnum(method->method_idnum()));
2764   }
2765 
2766   if (_member_names == NULL) {
2767     _member_names = new (ResourceObj::C_HEAP, mtClass) MemberNameTable(idnum_allocated_count());
2768   }
2769   _member_names->add_member_name(mem_name_wref);
2770   return true;
2771 }
2772 
2773 // -----------------------------------------------------------------------------------------------------
2774 // Printing
2775 
2776 #ifndef PRODUCT
2777 
2778 #define BULLET  " - "
2779 
2780 static const char* state_names[] = {
2781   "allocated", "loaded", "linked", "being_initialized", "fully_initialized", "initialization_error"
2782 };
2783 
2784 static void print_vtable(address self, intptr_t* start, int len, outputStream* st) {
2785   ResourceMark rm;
2786   int* forward_refs = NEW_RESOURCE_ARRAY(int, len);
2787   for (int i = 0; i < len; i++)  forward_refs[i] = 0;
2788   for (int i = 0; i < len; i++) {
2789     intptr_t e = start[i];
2790     st->print("%d : " INTPTR_FORMAT, i, e);
2791     if (forward_refs[i] != 0) {
2792       int from = forward_refs[i];
2793       int off = (int) start[from];
2794       st->print(" (offset %d <= [%d])", off, from);
2795     }
2796     if (e != 0 && ((Metadata*)e)->is_metaspace_object()) {
2797       st->print(" ");
2798       ((Metadata*)e)->print_value_on(st);
2799     } else if (self != NULL && e > 0 && e < 0x10000) {
2800       address location = self + e;
2801       int index = (int)((intptr_t*)location - start);
2802       st->print(" (offset %d => [%d])", (int)e, index);
2803       if (index >= 0 && index < len)
2804         forward_refs[index] = i;
2805     }
2806     st->cr();
2807   }
2808 }
2809 
2810 static void print_vtable(vtableEntry* start, int len, outputStream* st) {
2811   return print_vtable(NULL, reinterpret_cast<intptr_t*>(start), len, st);
2812 }
2813 
2814 template<typename T>
2815 static void print_array_on(outputStream* st, Array<T>* array) {
2816   if (array == NULL) { st->print_cr("NULL"); return; }
2817   array->print_value_on(st); st->cr();
2818   if (Verbose || WizardMode) {
2819     for (int i = 0; i < array->length(); i++) {
2820       st->print("%d : ", i); array->at(i)->print_value_on(st); st->cr();
2821     }
2822   }
2823 }
2824 static void print_array_on(outputStream* st, Array<int>* array) {
2825   if (array == NULL) { st->print_cr("NULL"); return; }
2826   array->print_value_on(st); st->cr();
2827   if (Verbose || WizardMode) {
2828     for (int i = 0; i < array->length(); i++) {
2829       st->print("%d : %d", i, array->at(i)); st->cr();
2830     }
2831   }
2832 }
2833 
2834 void InstanceKlass::print_on(outputStream* st) const {
2835   assert(is_klass(), "must be klass");
2836   Klass::print_on(st);
2837 
2838   st->print(BULLET"instance size:     %d", size_helper());                        st->cr();
2839   st->print(BULLET"klass size:        %d", size());                               st->cr();
2840   st->print(BULLET"access:            "); access_flags().print_on(st);            st->cr();
2841   st->print(BULLET"misc flags:        0x%x", _misc_flags);                        st->cr();
2842   st->print(BULLET"state:             "); st->print_cr("%s", state_names[_init_state]);
2843   st->print(BULLET"name:              "); name()->print_value_on(st);             st->cr();
2844   st->print(BULLET"super:             "); super()->print_value_on_maybe_null(st); st->cr();
2845   st->print(BULLET"sub:               ");
2846   Klass* sub = subklass();
2847   int n;
2848   for (n = 0; sub != NULL; n++, sub = sub->next_sibling()) {
2849     if (n < MaxSubklassPrintSize) {
2850       sub->print_value_on(st);
2851       st->print("   ");
2852     }
2853   }
2854   if (n >= MaxSubklassPrintSize) st->print("(" INTX_FORMAT " more klasses...)", n - MaxSubklassPrintSize);
2855   st->cr();
2856 
2857   if (is_interface()) {
2858     st->print_cr(BULLET"nof implementors:  %d", nof_implementors());
2859     if (nof_implementors() == 1) {
2860       st->print_cr(BULLET"implementor:    ");
2861       st->print("   ");
2862       implementor()->print_value_on(st);
2863       st->cr();
2864     }
2865   }
2866 
2867   st->print(BULLET"arrays:            "); array_klasses()->print_value_on_maybe_null(st); st->cr();
2868   st->print(BULLET"methods:           "); print_array_on(st, methods());
2869   st->print(BULLET"method ordering:   "); print_array_on(st, method_ordering());
2870   st->print(BULLET"default_methods:   "); print_array_on(st, default_methods());
2871   if (default_vtable_indices() != NULL) {
2872     st->print(BULLET"default vtable indices:   "); print_array_on(st, default_vtable_indices());
2873   }
2874   st->print(BULLET"local interfaces:  "); print_array_on(st, local_interfaces());
2875   st->print(BULLET"trans. interfaces: "); print_array_on(st, transitive_interfaces());
2876   st->print(BULLET"constants:         "); constants()->print_value_on(st);         st->cr();
2877   if (class_loader_data() != NULL) {
2878     st->print(BULLET"class loader data:  ");
2879     class_loader_data()->print_value_on(st);
2880     st->cr();
2881   }
2882   st->print(BULLET"host class:        "); host_klass()->print_value_on_maybe_null(st); st->cr();
2883   if (source_file_name() != NULL) {
2884     st->print(BULLET"source file:       ");
2885     source_file_name()->print_value_on(st);
2886     st->cr();
2887   }
2888   if (source_debug_extension() != NULL) {
2889     st->print(BULLET"source debug extension:       ");
2890     st->print("%s", source_debug_extension());
2891     st->cr();
2892   }
2893   st->print(BULLET"class annotations:       "); class_annotations()->print_value_on(st); st->cr();
2894   st->print(BULLET"class type annotations:  "); class_type_annotations()->print_value_on(st); st->cr();
2895   st->print(BULLET"field annotations:       "); fields_annotations()->print_value_on(st); st->cr();
2896   st->print(BULLET"field type annotations:  "); fields_type_annotations()->print_value_on(st); st->cr();
2897   {
2898     bool have_pv = false;
2899     // previous versions are linked together through the InstanceKlass
2900     for (InstanceKlass* pv_node = _previous_versions;
2901          pv_node != NULL;
2902          pv_node = pv_node->previous_versions()) {
2903       if (!have_pv)
2904         st->print(BULLET"previous version:  ");
2905       have_pv = true;
2906       pv_node->constants()->print_value_on(st);
2907     }
2908     if (have_pv) st->cr();
2909   }
2910 
2911   if (generic_signature() != NULL) {
2912     st->print(BULLET"generic signature: ");
2913     generic_signature()->print_value_on(st);
2914     st->cr();
2915   }
2916   st->print(BULLET"inner classes:     "); inner_classes()->print_value_on(st);     st->cr();
2917   st->print(BULLET"java mirror:       "); java_mirror()->print_value_on(st);       st->cr();
2918   st->print(BULLET"vtable length      %d  (start addr: " INTPTR_FORMAT ")", vtable_length(), p2i(start_of_vtable())); st->cr();
2919   if (vtable_length() > 0 && (Verbose || WizardMode))  print_vtable(start_of_vtable(), vtable_length(), st);
2920   st->print(BULLET"itable length      %d (start addr: " INTPTR_FORMAT ")", itable_length(), p2i(start_of_itable())); st->cr();
2921   if (itable_length() > 0 && (Verbose || WizardMode))  print_vtable(NULL, start_of_itable(), itable_length(), st);
2922   st->print_cr(BULLET"---- static fields (%d words):", static_field_size());
2923   FieldPrinter print_static_field(st);
2924   ((InstanceKlass*)this)->do_local_static_fields(&print_static_field);
2925   st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size());
2926   FieldPrinter print_nonstatic_field(st);
2927   InstanceKlass* ik = const_cast<InstanceKlass*>(this);
2928   ik->do_nonstatic_fields(&print_nonstatic_field);
2929 
2930   st->print(BULLET"non-static oop maps: ");
2931   OopMapBlock* map     = start_of_nonstatic_oop_maps();
2932   OopMapBlock* end_map = map + nonstatic_oop_map_count();
2933   while (map < end_map) {
2934     st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1));
2935     map++;
2936   }
2937   st->cr();
2938 }
2939 
2940 #endif //PRODUCT
2941 
2942 void InstanceKlass::print_value_on(outputStream* st) const {
2943   assert(is_klass(), "must be klass");
2944   if (Verbose || WizardMode)  access_flags().print_on(st);
2945   name()->print_value_on(st);
2946 }
2947 
2948 #ifndef PRODUCT
2949 
2950 void FieldPrinter::do_field(fieldDescriptor* fd) {
2951   _st->print(BULLET);
2952    if (_obj == NULL) {
2953      fd->print_on(_st);
2954      _st->cr();
2955    } else {
2956      fd->print_on_for(_st, _obj);
2957    }
2958 }
2959 
2960 
2961 void InstanceKlass::oop_print_on(oop obj, outputStream* st) {
2962   Klass::oop_print_on(obj, st);
2963 
2964   if (this == SystemDictionary::String_klass()) {
2965     typeArrayOop value  = java_lang_String::value(obj);
2966     juint        length = java_lang_String::length(obj);
2967     if (value != NULL &&
2968         value->is_typeArray() &&
2969         length <= (juint) value->length()) {
2970       st->print(BULLET"string: ");
2971       java_lang_String::print(obj, st);
2972       st->cr();
2973       if (!WizardMode)  return;  // that is enough
2974     }
2975   }
2976 
2977   st->print_cr(BULLET"---- fields (total size %d words):", oop_size(obj));
2978   FieldPrinter print_field(st, obj);
2979   do_nonstatic_fields(&print_field);
2980 
2981   if (this == SystemDictionary::Class_klass()) {
2982     st->print(BULLET"signature: ");
2983     java_lang_Class::print_signature(obj, st);
2984     st->cr();
2985     Klass* mirrored_klass = java_lang_Class::as_Klass(obj);
2986     st->print(BULLET"fake entry for mirror: ");
2987     mirrored_klass->print_value_on_maybe_null(st);
2988     st->cr();
2989     Klass* array_klass = java_lang_Class::array_klass(obj);
2990     st->print(BULLET"fake entry for array: ");
2991     array_klass->print_value_on_maybe_null(st);
2992     st->cr();
2993     st->print_cr(BULLET"fake entry for oop_size: %d", java_lang_Class::oop_size(obj));
2994     st->print_cr(BULLET"fake entry for static_oop_field_count: %d", java_lang_Class::static_oop_field_count(obj));
2995     Klass* real_klass = java_lang_Class::as_Klass(obj);
2996     if (real_klass != NULL && real_klass->is_instance_klass()) {
2997       InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field);
2998     }
2999   } else if (this == SystemDictionary::MethodType_klass()) {
3000     st->print(BULLET"signature: ");
3001     java_lang_invoke_MethodType::print_signature(obj, st);
3002     st->cr();
3003   }
3004 }
3005 
3006 #endif //PRODUCT
3007 
3008 void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) {
3009   st->print("a ");
3010   name()->print_value_on(st);
3011   obj->print_address_on(st);
3012   if (this == SystemDictionary::String_klass()
3013       && java_lang_String::value(obj) != NULL) {
3014     ResourceMark rm;
3015     int len = java_lang_String::length(obj);
3016     int plen = (len < 24 ? len : 12);
3017     char* str = java_lang_String::as_utf8_string(obj, 0, plen);
3018     st->print(" = \"%s\"", str);
3019     if (len > plen)
3020       st->print("...[%d]", len);
3021   } else if (this == SystemDictionary::Class_klass()) {
3022     Klass* k = java_lang_Class::as_Klass(obj);
3023     st->print(" = ");
3024     if (k != NULL) {
3025       k->print_value_on(st);
3026     } else {
3027       const char* tname = type2name(java_lang_Class::primitive_type(obj));
3028       st->print("%s", tname ? tname : "type?");
3029     }
3030   } else if (this == SystemDictionary::MethodType_klass()) {
3031     st->print(" = ");
3032     java_lang_invoke_MethodType::print_signature(obj, st);
3033   } else if (java_lang_boxing_object::is_instance(obj)) {
3034     st->print(" = ");
3035     java_lang_boxing_object::print(obj, st);
3036   } else if (this == SystemDictionary::LambdaForm_klass()) {
3037     oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj);
3038     if (vmentry != NULL) {
3039       st->print(" => ");
3040       vmentry->print_value_on(st);
3041     }
3042   } else if (this == SystemDictionary::MemberName_klass()) {
3043     Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj);
3044     if (vmtarget != NULL) {
3045       st->print(" = ");
3046       vmtarget->print_value_on(st);
3047     } else {
3048       java_lang_invoke_MemberName::clazz(obj)->print_value_on(st);
3049       st->print(".");
3050       java_lang_invoke_MemberName::name(obj)->print_value_on(st);
3051     }
3052   }
3053 }
3054 
3055 const char* InstanceKlass::internal_name() const {
3056   return external_name();
3057 }
3058 
3059 void InstanceKlass::print_loading_log(LogLevel::type type,
3060                                       ClassLoaderData* loader_data,
3061                                       const ClassFileStream* cfs) const {
3062   ResourceMark rm;
3063   outputStream* log;
3064 
3065   assert(type == LogLevel::Info || type == LogLevel::Debug, "sanity");
3066 
3067   if (type == LogLevel::Info) {
3068     log = LogHandle(classload)::info_stream();
3069   } else {
3070     assert(type == LogLevel::Debug,
3071            "print_loading_log supports only Debug and Info levels");
3072     log = LogHandle(classload)::debug_stream();
3073   }
3074 
3075   // Name and class hierarchy info
3076   log->print("%s", external_name());
3077 
3078   // Source
3079   if (cfs != NULL) {
3080     if (cfs->source() != NULL) {
3081       log->print(" source: %s", cfs->source());
3082     } else if (loader_data == ClassLoaderData::the_null_class_loader_data()) {
3083       Thread* THREAD = Thread::current();
3084       Klass* caller =
3085             THREAD->is_Java_thread()
3086                 ? ((JavaThread*)THREAD)->security_get_caller_class(1)
3087                 : NULL;
3088       // caller can be NULL, for example, during a JVMTI VM_Init hook
3089       if (caller != NULL) {
3090         log->print(" source: instance of %s", caller->external_name());
3091       } else {
3092         // source is unknown
3093       }
3094     } else {
3095       Handle class_loader(loader_data->class_loader());
3096       log->print(" source: %s", class_loader->klass()->external_name());
3097     }
3098   } else {
3099     log->print(" source: shared objects file");
3100   }
3101 
3102   if (type == LogLevel::Debug) {
3103     // Class hierarchy info
3104     log->print(" klass: " INTPTR_FORMAT " super: " INTPTR_FORMAT,
3105                p2i(this),  p2i(superklass()));
3106 
3107     if (local_interfaces() != NULL && local_interfaces()->length() > 0) {
3108       log->print(" interfaces:");
3109       int length = local_interfaces()->length();
3110       for (int i = 0; i < length; i++) {
3111         log->print(" " INTPTR_FORMAT,
3112                    p2i(InstanceKlass::cast(local_interfaces()->at(i))));
3113       }
3114     }
3115 
3116     // Class loader
3117     log->print(" loader: [");
3118     loader_data->print_value_on(log);
3119     log->print("]");
3120 
3121     // Classfile checksum
3122     if (cfs) {
3123       log->print(" bytes: %d checksum: %08x",
3124                  cfs->length(),
3125                  ClassLoader::crc32(0, (const char*)cfs->buffer(),
3126                  cfs->length()));
3127     }
3128   }
3129   log->cr();
3130 }
3131 
3132 #if INCLUDE_SERVICES
3133 // Size Statistics
3134 void InstanceKlass::collect_statistics(KlassSizeStats *sz) const {
3135   Klass::collect_statistics(sz);
3136 
3137   sz->_inst_size  = wordSize * size_helper();
3138   sz->_vtab_bytes = wordSize * vtable_length();
3139   sz->_itab_bytes = wordSize * itable_length();
3140   sz->_nonstatic_oopmap_bytes = wordSize * nonstatic_oop_map_size();
3141 
3142   int n = 0;
3143   n += (sz->_methods_array_bytes         = sz->count_array(methods()));
3144   n += (sz->_method_ordering_bytes       = sz->count_array(method_ordering()));
3145   n += (sz->_local_interfaces_bytes      = sz->count_array(local_interfaces()));
3146   n += (sz->_transitive_interfaces_bytes = sz->count_array(transitive_interfaces()));
3147   n += (sz->_fields_bytes                = sz->count_array(fields()));
3148   n += (sz->_inner_classes_bytes         = sz->count_array(inner_classes()));
3149   sz->_ro_bytes += n;
3150 
3151   const ConstantPool* cp = constants();
3152   if (cp) {
3153     cp->collect_statistics(sz);
3154   }
3155 
3156   const Annotations* anno = annotations();
3157   if (anno) {
3158     anno->collect_statistics(sz);
3159   }
3160 
3161   const Array<Method*>* methods_array = methods();
3162   if (methods()) {
3163     for (int i = 0; i < methods_array->length(); i++) {
3164       Method* method = methods_array->at(i);
3165       if (method) {
3166         sz->_method_count ++;
3167         method->collect_statistics(sz);
3168       }
3169     }
3170   }
3171 }
3172 #endif // INCLUDE_SERVICES
3173 
3174 // Verification
3175 
3176 class VerifyFieldClosure: public OopClosure {
3177  protected:
3178   template <class T> void do_oop_work(T* p) {
3179     oop obj = oopDesc::load_decode_heap_oop(p);
3180     if (!obj->is_oop_or_null()) {
3181       tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p2i(p), p2i(obj));
3182       Universe::print_on(tty);
3183       guarantee(false, "boom");
3184     }
3185   }
3186  public:
3187   virtual void do_oop(oop* p)       { VerifyFieldClosure::do_oop_work(p); }
3188   virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); }
3189 };
3190 
3191 void InstanceKlass::verify_on(outputStream* st) {
3192 #ifndef PRODUCT
3193   // Avoid redundant verifies, this really should be in product.
3194   if (_verify_count == Universe::verify_count()) return;
3195   _verify_count = Universe::verify_count();
3196 #endif
3197 
3198   // Verify Klass
3199   Klass::verify_on(st);
3200 
3201   // Verify that klass is present in ClassLoaderData
3202   guarantee(class_loader_data()->contains_klass(this),
3203             "this class isn't found in class loader data");
3204 
3205   // Verify vtables
3206   if (is_linked()) {
3207     ResourceMark rm;
3208     // $$$ This used to be done only for m/s collections.  Doing it
3209     // always seemed a valid generalization.  (DLD -- 6/00)
3210     vtable()->verify(st);
3211   }
3212 
3213   // Verify first subklass
3214   if (subklass() != NULL) {
3215     guarantee(subklass()->is_klass(), "should be klass");
3216   }
3217 
3218   // Verify siblings
3219   Klass* super = this->super();
3220   Klass* sib = next_sibling();
3221   if (sib != NULL) {
3222     if (sib == this) {
3223       fatal("subclass points to itself " PTR_FORMAT, p2i(sib));
3224     }
3225 
3226     guarantee(sib->is_klass(), "should be klass");
3227     guarantee(sib->super() == super, "siblings should have same superklass");
3228   }
3229 
3230   // Verify implementor fields
3231   Klass* im = implementor();
3232   if (im != NULL) {
3233     guarantee(is_interface(), "only interfaces should have implementor set");
3234     guarantee(im->is_klass(), "should be klass");
3235     guarantee(!im->is_interface() || im == this,
3236       "implementors cannot be interfaces");
3237   }
3238 
3239   // Verify local interfaces
3240   if (local_interfaces()) {
3241     Array<Klass*>* local_interfaces = this->local_interfaces();
3242     for (int j = 0; j < local_interfaces->length(); j++) {
3243       Klass* e = local_interfaces->at(j);
3244       guarantee(e->is_klass() && e->is_interface(), "invalid local interface");
3245     }
3246   }
3247 
3248   // Verify transitive interfaces
3249   if (transitive_interfaces() != NULL) {
3250     Array<Klass*>* transitive_interfaces = this->transitive_interfaces();
3251     for (int j = 0; j < transitive_interfaces->length(); j++) {
3252       Klass* e = transitive_interfaces->at(j);
3253       guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface");
3254     }
3255   }
3256 
3257   // Verify methods
3258   if (methods() != NULL) {
3259     Array<Method*>* methods = this->methods();
3260     for (int j = 0; j < methods->length(); j++) {
3261       guarantee(methods->at(j)->is_method(), "non-method in methods array");
3262     }
3263     for (int j = 0; j < methods->length() - 1; j++) {
3264       Method* m1 = methods->at(j);
3265       Method* m2 = methods->at(j + 1);
3266       guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3267     }
3268   }
3269 
3270   // Verify method ordering
3271   if (method_ordering() != NULL) {
3272     Array<int>* method_ordering = this->method_ordering();
3273     int length = method_ordering->length();
3274     if (JvmtiExport::can_maintain_original_method_order() ||
3275         ((UseSharedSpaces || DumpSharedSpaces) && length != 0)) {
3276       guarantee(length == methods()->length(), "invalid method ordering length");
3277       jlong sum = 0;
3278       for (int j = 0; j < length; j++) {
3279         int original_index = method_ordering->at(j);
3280         guarantee(original_index >= 0, "invalid method ordering index");
3281         guarantee(original_index < length, "invalid method ordering index");
3282         sum += original_index;
3283       }
3284       // Verify sum of indices 0,1,...,length-1
3285       guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum");
3286     } else {
3287       guarantee(length == 0, "invalid method ordering length");
3288     }
3289   }
3290 
3291   // Verify default methods
3292   if (default_methods() != NULL) {
3293     Array<Method*>* methods = this->default_methods();
3294     for (int j = 0; j < methods->length(); j++) {
3295       guarantee(methods->at(j)->is_method(), "non-method in methods array");
3296     }
3297     for (int j = 0; j < methods->length() - 1; j++) {
3298       Method* m1 = methods->at(j);
3299       Method* m2 = methods->at(j + 1);
3300       guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3301     }
3302   }
3303 
3304   // Verify JNI static field identifiers
3305   if (jni_ids() != NULL) {
3306     jni_ids()->verify(this);
3307   }
3308 
3309   // Verify other fields
3310   if (array_klasses() != NULL) {
3311     guarantee(array_klasses()->is_klass(), "should be klass");
3312   }
3313   if (constants() != NULL) {
3314     guarantee(constants()->is_constantPool(), "should be constant pool");
3315   }
3316   const Klass* host = host_klass();
3317   if (host != NULL) {
3318     guarantee(host->is_klass(), "should be klass");
3319   }
3320 }
3321 
3322 void InstanceKlass::oop_verify_on(oop obj, outputStream* st) {
3323   Klass::oop_verify_on(obj, st);
3324   VerifyFieldClosure blk;
3325   obj->oop_iterate_no_header(&blk);
3326 }
3327 
3328 
3329 // JNIid class for jfieldIDs only
3330 // Note to reviewers:
3331 // These JNI functions are just moved over to column 1 and not changed
3332 // in the compressed oops workspace.
3333 JNIid::JNIid(Klass* holder, int offset, JNIid* next) {
3334   _holder = holder;
3335   _offset = offset;
3336   _next = next;
3337   debug_only(_is_static_field_id = false;)
3338 }
3339 
3340 
3341 JNIid* JNIid::find(int offset) {
3342   JNIid* current = this;
3343   while (current != NULL) {
3344     if (current->offset() == offset) return current;
3345     current = current->next();
3346   }
3347   return NULL;
3348 }
3349 
3350 void JNIid::deallocate(JNIid* current) {
3351   while (current != NULL) {
3352     JNIid* next = current->next();
3353     delete current;
3354     current = next;
3355   }
3356 }
3357 
3358 
3359 void JNIid::verify(Klass* holder) {
3360   int first_field_offset  = InstanceMirrorKlass::offset_of_static_fields();
3361   int end_field_offset;
3362   end_field_offset = first_field_offset + (InstanceKlass::cast(holder)->static_field_size() * wordSize);
3363 
3364   JNIid* current = this;
3365   while (current != NULL) {
3366     guarantee(current->holder() == holder, "Invalid klass in JNIid");
3367 #ifdef ASSERT
3368     int o = current->offset();
3369     if (current->is_static_field_id()) {
3370       guarantee(o >= first_field_offset  && o < end_field_offset,  "Invalid static field offset in JNIid");
3371     }
3372 #endif
3373     current = current->next();
3374   }
3375 }
3376 
3377 
3378 #ifdef ASSERT
3379 void InstanceKlass::set_init_state(ClassState state) {
3380   bool good_state = is_shared() ? (_init_state <= state)
3381                                                : (_init_state < state);
3382   assert(good_state || state == allocated, "illegal state transition");
3383   _init_state = (u1)state;
3384 }
3385 #endif
3386 
3387 
3388 
3389 // RedefineClasses() support for previous versions:
3390 int InstanceKlass::_previous_version_count = 0;
3391 
3392 // Purge previous versions before adding new previous versions of the class.
3393 void InstanceKlass::purge_previous_versions(InstanceKlass* ik) {
3394   if (ik->previous_versions() != NULL) {
3395     // This klass has previous versions so see what we can cleanup
3396     // while it is safe to do so.
3397 
3398     int deleted_count = 0;    // leave debugging breadcrumbs
3399     int live_count = 0;
3400     ClassLoaderData* loader_data = ik->class_loader_data();
3401     assert(loader_data != NULL, "should never be null");
3402 
3403     // RC_TRACE macro has an embedded ResourceMark
3404     RC_TRACE(0x00000200, ("purge: %s: previous versions", ik->external_name()));
3405 
3406     // previous versions are linked together through the InstanceKlass
3407     InstanceKlass* pv_node = ik->previous_versions();
3408     InstanceKlass* last = ik;
3409     int version = 0;
3410 
3411     // check the previous versions list
3412     for (; pv_node != NULL; ) {
3413 
3414       ConstantPool* pvcp = pv_node->constants();
3415       assert(pvcp != NULL, "cp ref was unexpectedly cleared");
3416 
3417       if (!pvcp->on_stack()) {
3418         // If the constant pool isn't on stack, none of the methods
3419         // are executing.  Unlink this previous_version.
3420         // The previous version InstanceKlass is on the ClassLoaderData deallocate list
3421         // so will be deallocated during the next phase of class unloading.
3422         RC_TRACE(0x00000200, ("purge: previous version " INTPTR_FORMAT " is dead",
3423                               p2i(pv_node)));
3424         // For debugging purposes.
3425         pv_node->set_is_scratch_class();
3426         pv_node->class_loader_data()->add_to_deallocate_list(pv_node);
3427         pv_node = pv_node->previous_versions();
3428         last->link_previous_versions(pv_node);
3429         deleted_count++;
3430         version++;
3431         continue;
3432       } else {
3433         RC_TRACE(0x00000200, ("purge: previous version " INTPTR_FORMAT " is alive",
3434                               p2i(pv_node)));
3435         assert(pvcp->pool_holder() != NULL, "Constant pool with no holder");
3436         guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack");
3437         live_count++;
3438       }
3439 
3440       // At least one method is live in this previous version.
3441       // Reset dead EMCP methods not to get breakpoints.
3442       // All methods are deallocated when all of the methods for this class are no
3443       // longer running.
3444       Array<Method*>* method_refs = pv_node->methods();
3445       if (method_refs != NULL) {
3446         RC_TRACE(0x00000200, ("purge: previous methods length=%d",
3447           method_refs->length()));
3448         for (int j = 0; j < method_refs->length(); j++) {
3449           Method* method = method_refs->at(j);
3450 
3451           if (!method->on_stack()) {
3452             // no breakpoints for non-running methods
3453             if (method->is_running_emcp()) {
3454               method->set_running_emcp(false);
3455             }
3456           } else {
3457             assert (method->is_obsolete() || method->is_running_emcp(),
3458                     "emcp method cannot run after emcp bit is cleared");
3459             // RC_TRACE macro has an embedded ResourceMark
3460             RC_TRACE(0x00000200,
3461               ("purge: %s(%s): prev method @%d in version @%d is alive",
3462               method->name()->as_C_string(),
3463               method->signature()->as_C_string(), j, version));
3464           }
3465         }
3466       }
3467       // next previous version
3468       last = pv_node;
3469       pv_node = pv_node->previous_versions();
3470       version++;
3471     }
3472     RC_TRACE(0x00000200,
3473       ("purge: previous version stats: live=%d, deleted=%d", live_count,
3474       deleted_count));
3475   }
3476 }
3477 
3478 void InstanceKlass::mark_newly_obsolete_methods(Array<Method*>* old_methods,
3479                                                 int emcp_method_count) {
3480   int obsolete_method_count = old_methods->length() - emcp_method_count;
3481 
3482   if (emcp_method_count != 0 && obsolete_method_count != 0 &&
3483       _previous_versions != NULL) {
3484     // We have a mix of obsolete and EMCP methods so we have to
3485     // clear out any matching EMCP method entries the hard way.
3486     int local_count = 0;
3487     for (int i = 0; i < old_methods->length(); i++) {
3488       Method* old_method = old_methods->at(i);
3489       if (old_method->is_obsolete()) {
3490         // only obsolete methods are interesting
3491         Symbol* m_name = old_method->name();
3492         Symbol* m_signature = old_method->signature();
3493 
3494         // previous versions are linked together through the InstanceKlass
3495         int j = 0;
3496         for (InstanceKlass* prev_version = _previous_versions;
3497              prev_version != NULL;
3498              prev_version = prev_version->previous_versions(), j++) {
3499 
3500           Array<Method*>* method_refs = prev_version->methods();
3501           for (int k = 0; k < method_refs->length(); k++) {
3502             Method* method = method_refs->at(k);
3503 
3504             if (!method->is_obsolete() &&
3505                 method->name() == m_name &&
3506                 method->signature() == m_signature) {
3507               // The current RedefineClasses() call has made all EMCP
3508               // versions of this method obsolete so mark it as obsolete
3509               RC_TRACE(0x00000400,
3510                 ("add: %s(%s): flush obsolete method @%d in version @%d",
3511                 m_name->as_C_string(), m_signature->as_C_string(), k, j));
3512 
3513               method->set_is_obsolete();
3514               break;
3515             }
3516           }
3517 
3518           // The previous loop may not find a matching EMCP method, but
3519           // that doesn't mean that we can optimize and not go any
3520           // further back in the PreviousVersion generations. The EMCP
3521           // method for this generation could have already been made obsolete,
3522           // but there still may be an older EMCP method that has not
3523           // been made obsolete.
3524         }
3525 
3526         if (++local_count >= obsolete_method_count) {
3527           // no more obsolete methods so bail out now
3528           break;
3529         }
3530       }
3531     }
3532   }
3533 }
3534 
3535 // Save the scratch_class as the previous version if any of the methods are running.
3536 // The previous_versions are used to set breakpoints in EMCP methods and they are
3537 // also used to clean MethodData links to redefined methods that are no longer running.
3538 void InstanceKlass::add_previous_version(instanceKlassHandle scratch_class,
3539                                          int emcp_method_count) {
3540   assert(Thread::current()->is_VM_thread(),
3541          "only VMThread can add previous versions");
3542 
3543   // RC_TRACE macro has an embedded ResourceMark
3544   RC_TRACE(0x00000400, ("adding previous version ref for %s, EMCP_cnt=%d",
3545     scratch_class->external_name(), emcp_method_count));
3546 
3547   // Clean out old previous versions
3548   purge_previous_versions(this);
3549 
3550   // Mark newly obsolete methods in remaining previous versions.  An EMCP method from
3551   // a previous redefinition may be made obsolete by this redefinition.
3552   Array<Method*>* old_methods = scratch_class->methods();
3553   mark_newly_obsolete_methods(old_methods, emcp_method_count);
3554 
3555   // If the constant pool for this previous version of the class
3556   // is not marked as being on the stack, then none of the methods
3557   // in this previous version of the class are on the stack so
3558   // we don't need to add this as a previous version.
3559   ConstantPool* cp_ref = scratch_class->constants();
3560   if (!cp_ref->on_stack()) {
3561     RC_TRACE(0x00000400, ("add: scratch class not added; no methods are running"));
3562     // For debugging purposes.
3563     scratch_class->set_is_scratch_class();
3564     scratch_class->class_loader_data()->add_to_deallocate_list(scratch_class());
3565     // Update count for class unloading.
3566     _previous_version_count--;
3567     return;
3568   }
3569 
3570   if (emcp_method_count != 0) {
3571     // At least one method is still running, check for EMCP methods
3572     for (int i = 0; i < old_methods->length(); i++) {
3573       Method* old_method = old_methods->at(i);
3574       if (!old_method->is_obsolete() && old_method->on_stack()) {
3575         // if EMCP method (not obsolete) is on the stack, mark as EMCP so that
3576         // we can add breakpoints for it.
3577 
3578         // We set the method->on_stack bit during safepoints for class redefinition
3579         // and use this bit to set the is_running_emcp bit.
3580         // After the safepoint, the on_stack bit is cleared and the running emcp
3581         // method may exit.   If so, we would set a breakpoint in a method that
3582         // is never reached, but this won't be noticeable to the programmer.
3583         old_method->set_running_emcp(true);
3584         RC_TRACE(0x00000400, ("add: EMCP method %s is on_stack " INTPTR_FORMAT,
3585                               old_method->name_and_sig_as_C_string(), p2i(old_method)));
3586       } else if (!old_method->is_obsolete()) {
3587         RC_TRACE(0x00000400, ("add: EMCP method %s is NOT on_stack " INTPTR_FORMAT,
3588                               old_method->name_and_sig_as_C_string(), p2i(old_method)));
3589       }
3590     }
3591   }
3592 
3593   // Add previous version if any methods are still running.
3594   RC_TRACE(0x00000400, ("add: scratch class added; one of its methods is on_stack"));
3595   assert(scratch_class->previous_versions() == NULL, "shouldn't have a previous version");
3596   scratch_class->link_previous_versions(previous_versions());
3597   link_previous_versions(scratch_class());
3598   // Update count for class unloading.
3599   _previous_version_count++;
3600 } // end add_previous_version()
3601 
3602 
3603 Method* InstanceKlass::method_with_idnum(int idnum) {
3604   Method* m = NULL;
3605   if (idnum < methods()->length()) {
3606     m = methods()->at(idnum);
3607   }
3608   if (m == NULL || m->method_idnum() != idnum) {
3609     for (int index = 0; index < methods()->length(); ++index) {
3610       m = methods()->at(index);
3611       if (m->method_idnum() == idnum) {
3612         return m;
3613       }
3614     }
3615     // None found, return null for the caller to handle.
3616     return NULL;
3617   }
3618   return m;
3619 }
3620 
3621 
3622 Method* InstanceKlass::method_with_orig_idnum(int idnum) {
3623   if (idnum >= methods()->length()) {
3624     return NULL;
3625   }
3626   Method* m = methods()->at(idnum);
3627   if (m != NULL && m->orig_method_idnum() == idnum) {
3628     return m;
3629   }
3630   // Obsolete method idnum does not match the original idnum
3631   for (int index = 0; index < methods()->length(); ++index) {
3632     m = methods()->at(index);
3633     if (m->orig_method_idnum() == idnum) {
3634       return m;
3635     }
3636   }
3637   // None found, return null for the caller to handle.
3638   return NULL;
3639 }
3640 
3641 
3642 Method* InstanceKlass::method_with_orig_idnum(int idnum, int version) {
3643   InstanceKlass* holder = get_klass_version(version);
3644   if (holder == NULL) {
3645     return NULL; // The version of klass is gone, no method is found
3646   }
3647   Method* method = holder->method_with_orig_idnum(idnum);
3648   return method;
3649 }
3650 
3651 
3652 jint InstanceKlass::get_cached_class_file_len() {
3653   return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file);
3654 }
3655 
3656 unsigned char * InstanceKlass::get_cached_class_file_bytes() {
3657   return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file);
3658 }
3659 
3660 #define THROW_DVT_ERROR(s) \
3661   Exceptions::fthrow(THREAD_AND_LOCATION, vmSymbols::java_lang_InternalError(), \
3662       "DeriveValueType class '%s' %s", external_name(),(s)); \
3663       return
3664 
3665 void InstanceKlass::create_derive_value_type(Handle class_loader, Handle protection_domain, TRAPS) {
3666   ResourceMark rm(THREAD);
3667   HandleMark hm(THREAD);
3668 
3669   if (!ValhallaMVT1_0) {
3670     return; // Silent fail
3671   }
3672   // Validate VCC...
3673   if (!has_nonstatic_fields()) {
3674     THROW_DVT_ERROR("has no instance fields");
3675   }
3676   if (is_value()) {
3677     THROW_DVT_ERROR("is already a value type");
3678   }
3679   if (!access_flags().is_final()) {
3680     THROW_DVT_ERROR("is not a final class");
3681   }
3682   if (super() != SystemDictionary::Object_klass()) {
3683     THROW_DVT_ERROR("does not derive from Object only");
3684   }
3685 
3686   // All non-static are final
3687   GrowableArray<Handle>* fields = new GrowableArray<Handle>(THREAD, java_fields_count()*2);
3688   GrowableArray<jint>* fields_access = new GrowableArray<jint>(THREAD, java_fields_count()*2);
3689   for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
3690     AccessFlags access_flags = fs.access_flags();
3691     if (access_flags.is_static()) {
3692       continue;
3693     }
3694     if (!access_flags.is_final()) {
3695       THROW_DVT_ERROR("contains non-final instance field");
3696     }
3697     jint flags = access_flags.get_flags();
3698     // Remember the field name, signature, access modifiers
3699     Handle h = java_lang_String::create_from_symbol(fs.name(), CHECK);
3700     fields->append(h);
3701     h = java_lang_String::create_from_symbol(fs.signature(), CHECK);
3702     fields->append(h);
3703     fields_access->append(access_flags.get_flags());
3704   }
3705 
3706   // Generate DVT...
3707   log_debug(classload)("Cooking DVT for VCC %s", external_name());
3708   const char*  this_name     = name()->as_C_string();
3709 
3710   // Assemble the Java args...field descriptor array
3711   objArrayHandle fdarr = oopFactory::new_objectArray(fields->length(), CHECK);
3712   for (int i = 0; i < fields->length(); i++) {
3713     fdarr->obj_at_put(i, fields->at(i)());
3714   }
3715   //...field access modifiers array
3716   typeArrayHandle faarr = oopFactory::new_intArray(fields_access->length(), CHECK);
3717   for (int i = 0; i < fields_access->length(); i++) {
3718     faarr->int_at_put(i, fields_access->at(i));
3719   }
3720 
3721   Handle vcc_name_h = java_lang_String::create_from_symbol(name(), CHECK);
3722   // Upcall to our Java helper...
3723   JavaValue result(T_OBJECT);
3724   JavaCallArguments args(5);
3725   args.push_oop(vcc_name_h);
3726   args.push_oop(class_loader);
3727   args.push_oop(protection_domain);
3728   args.push_oop(fdarr);
3729   args.push_oop(faarr);
3730   JavaCalls::call_static(&result,
3731                          SystemDictionary::Valhalla_MVT1_0_klass(),
3732                          vmSymbols::valhalla_shady_MVT1_0_createDerivedValueType(),
3733                          vmSymbols::valhalla_shady_MVT1_0_createDerivedValueType_signature(),
3734                          &args,
3735                          CHECK);
3736   Handle returned((oop) result.get_jobject());
3737   if (returned.is_null()) {
3738     THROW_DVT_ERROR("unknown error deriving value type");
3739   }
3740   TempNewSymbol dvt_name_sym = java_lang_String::as_symbol(returned, CHECK);
3741 
3742   Klass* dvt_klass = SystemDictionary::resolve_or_null(dvt_name_sym,
3743                                                        class_loader,
3744                                                        protection_domain,
3745                                                        CHECK);
3746   if (!dvt_klass->is_value()) {
3747     THROW_DVT_ERROR("failed to resolve derived value type");
3748   }
3749   /**
3750    * Found it, let's point to each other to denote "is_derive_vt()"...
3751    */
3752   ValueKlass* vt_klass = ValueKlass::cast(dvt_klass);
3753   assert(vt_klass->class_loader() == class_loader(), "DVT Not the same class loader as VCC");
3754   _derive_value_type_klass = vt_klass;
3755   vt_klass->_derive_value_type_klass = this;
3756   log_debug(classload)("Cooked DVT %s for VCC %s", vt_klass->external_name(), external_name());
3757 }
3758