1 /*
   2  * Copyright (c) 1997, 2018, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #include "precompiled.hpp"
  26 #include "jvm.h"
  27 #include "aot/aotLoader.hpp"
  28 #include "classfile/classFileParser.hpp"
  29 #include "classfile/classFileStream.hpp"
  30 #include "classfile/classLoader.hpp"
  31 #include "classfile/classLoaderData.inline.hpp"
  32 #include "classfile/javaClasses.hpp"
  33 #include "classfile/moduleEntry.hpp"
  34 #include "classfile/systemDictionary.hpp"
  35 #include "classfile/systemDictionaryShared.hpp"
  36 #include "classfile/verifier.hpp"
  37 #include "classfile/vmSymbols.hpp"
  38 #include "code/dependencyContext.hpp"
  39 #include "compiler/compileBroker.hpp"
  40 #include "gc/shared/collectedHeap.inline.hpp"
  41 #include "interpreter/oopMapCache.hpp"
  42 #include "interpreter/rewriter.hpp"
  43 #include "jvmtifiles/jvmti.h"
  44 #include "logging/log.hpp"
  45 #include "logging/logMessage.hpp"
  46 #include "logging/logStream.hpp"
  47 #include "memory/allocation.inline.hpp"
  48 #include "memory/heapInspection.hpp"
  49 #include "memory/iterator.inline.hpp"
  50 #include "memory/metadataFactory.hpp"
  51 #include "memory/metaspaceClosure.hpp"
  52 #include "memory/metaspaceShared.hpp"
  53 #include "memory/oopFactory.hpp"
  54 #include "memory/resourceArea.hpp"
  55 #include "oops/fieldStreams.hpp"
  56 #include "oops/instanceClassLoaderKlass.hpp"
  57 #include "oops/instanceKlass.inline.hpp"
  58 #include "oops/instanceMirrorKlass.hpp"
  59 #include "oops/instanceOop.hpp"
  60 #include "oops/klass.inline.hpp"
  61 #include "oops/method.hpp"
  62 #include "oops/oop.inline.hpp"
  63 #include "oops/symbol.hpp"
  64 #include "prims/jvmtiExport.hpp"
  65 #include "prims/jvmtiRedefineClasses.hpp"
  66 #include "prims/jvmtiThreadState.hpp"
  67 #include "prims/methodComparator.hpp"
  68 #include "runtime/atomic.hpp"
  69 #include "runtime/fieldDescriptor.inline.hpp"
  70 #include "runtime/handles.inline.hpp"
  71 #include "runtime/javaCalls.hpp"
  72 #include "runtime/mutexLocker.hpp"
  73 #include "runtime/orderAccess.hpp"
  74 #include "runtime/thread.inline.hpp"
  75 #include "services/classLoadingService.hpp"
  76 #include "services/threadService.hpp"
  77 #include "utilities/dtrace.hpp"
  78 #include "utilities/macros.hpp"
  79 #include "utilities/stringUtils.hpp"
  80 #ifdef COMPILER1
  81 #include "c1/c1_Compiler.hpp"
  82 #endif
  83 #if INCLUDE_JFR
  84 #include "jfr/jfrEvents.hpp"
  85 #endif
  86 
  87 
  88 #ifdef DTRACE_ENABLED
  89 
  90 
  91 #define HOTSPOT_CLASS_INITIALIZATION_required HOTSPOT_CLASS_INITIALIZATION_REQUIRED
  92 #define HOTSPOT_CLASS_INITIALIZATION_recursive HOTSPOT_CLASS_INITIALIZATION_RECURSIVE
  93 #define HOTSPOT_CLASS_INITIALIZATION_concurrent HOTSPOT_CLASS_INITIALIZATION_CONCURRENT
  94 #define HOTSPOT_CLASS_INITIALIZATION_erroneous HOTSPOT_CLASS_INITIALIZATION_ERRONEOUS
  95 #define HOTSPOT_CLASS_INITIALIZATION_super__failed HOTSPOT_CLASS_INITIALIZATION_SUPER_FAILED
  96 #define HOTSPOT_CLASS_INITIALIZATION_clinit HOTSPOT_CLASS_INITIALIZATION_CLINIT
  97 #define HOTSPOT_CLASS_INITIALIZATION_error HOTSPOT_CLASS_INITIALIZATION_ERROR
  98 #define HOTSPOT_CLASS_INITIALIZATION_end HOTSPOT_CLASS_INITIALIZATION_END
  99 #define DTRACE_CLASSINIT_PROBE(type, thread_type)                \
 100   {                                                              \
 101     char* data = NULL;                                           \
 102     int len = 0;                                                 \
 103     Symbol* clss_name = name();                                  \
 104     if (clss_name != NULL) {                                     \
 105       data = (char*)clss_name->bytes();                          \
 106       len = clss_name->utf8_length();                            \
 107     }                                                            \
 108     HOTSPOT_CLASS_INITIALIZATION_##type(                         \
 109       data, len, (void*)class_loader(), thread_type);            \
 110   }
 111 
 112 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait)     \
 113   {                                                              \
 114     char* data = NULL;                                           \
 115     int len = 0;                                                 \
 116     Symbol* clss_name = name();                                  \
 117     if (clss_name != NULL) {                                     \
 118       data = (char*)clss_name->bytes();                          \
 119       len = clss_name->utf8_length();                            \
 120     }                                                            \
 121     HOTSPOT_CLASS_INITIALIZATION_##type(                         \
 122       data, len, (void*)class_loader(), thread_type, wait);      \
 123   }
 124 
 125 #else //  ndef DTRACE_ENABLED
 126 
 127 #define DTRACE_CLASSINIT_PROBE(type, thread_type)
 128 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait)
 129 
 130 #endif //  ndef DTRACE_ENABLED
 131 
 132 static inline bool is_class_loader(const Symbol* class_name,
 133                                    const ClassFileParser& parser) {
 134   assert(class_name != NULL, "invariant");
 135 
 136   if (class_name == vmSymbols::java_lang_ClassLoader()) {
 137     return true;
 138   }
 139 
 140   if (SystemDictionary::ClassLoader_klass_loaded()) {
 141     const Klass* const super_klass = parser.super_klass();
 142     if (super_klass != NULL) {
 143       if (super_klass->is_subtype_of(SystemDictionary::ClassLoader_klass())) {
 144         return true;
 145       }
 146     }
 147   }
 148   return false;
 149 }
 150 
 151 // called to verify that k is a member of this nest
 152 bool InstanceKlass::has_nest_member(InstanceKlass* k, TRAPS) const {
 153   if (_nest_members == NULL || _nest_members == Universe::the_empty_short_array()) {
 154     if (log_is_enabled(Trace, class, nestmates)) {
 155       ResourceMark rm(THREAD);
 156       log_trace(class, nestmates)("Checked nest membership of %s in non-nest-host class %s",
 157                                   k->external_name(), this->external_name());
 158     }
 159     return false;
 160   }
 161 
 162   if (log_is_enabled(Trace, class, nestmates)) {
 163     ResourceMark rm(THREAD);
 164     log_trace(class, nestmates)("Checking nest membership of %s in %s",
 165                                 k->external_name(), this->external_name());
 166   }
 167 
 168   // Check for a resolved cp entry , else fall back to a name check.
 169   // We don't want to resolve any class other than the one being checked.
 170   for (int i = 0; i < _nest_members->length(); i++) {
 171     int cp_index = _nest_members->at(i);
 172     if (_constants->tag_at(cp_index).is_klass()) {
 173       Klass* k2 = _constants->klass_at(cp_index, CHECK_false);
 174       if (k2 == k) {
 175         log_trace(class, nestmates)("- class is listed at nest_members[%d] => cp[%d]", i, cp_index);
 176         return true;
 177       }
 178     }
 179     else {
 180       Symbol* name = _constants->klass_name_at(cp_index);
 181       if (name == k->name()) {
 182         log_trace(class, nestmates)("- Found it at nest_members[%d] => cp[%d]", i, cp_index);
 183 
 184         // names match so check actual klass - this may trigger class loading if
 185         // it doesn't match (but that should be impossible)
 186         Klass* k2 = _constants->klass_at(cp_index, CHECK_false);
 187         if (k2 == k) {
 188           log_trace(class, nestmates)("- class is listed as a nest member");
 189           return true;
 190         }
 191         else {
 192           // same name but different klass!
 193           log_trace(class, nestmates)(" - klass comparison failed!");
 194           // can't have two names the same, so we're done
 195           return false;
 196         }
 197       }
 198     }
 199   }
 200   log_trace(class, nestmates)("- class is NOT a nest member!");
 201   return false;
 202 }
 203 
 204 // Return nest-host class, resolving, validating and saving it if needed.
 205 // In cases where this is called from a thread that can not do classloading
 206 // (such as a native JIT thread) then we simply return NULL, which in turn
 207 // causes the access check to return false. Such code will retry the access
 208 // from a more suitable environment later.
 209 InstanceKlass* InstanceKlass::nest_host(Symbol* validationException, TRAPS) {
 210   InstanceKlass* nest_host_k = _nest_host;
 211   if (nest_host_k == NULL) {
 212     // need to resolve and save our nest-host class. This could be attempted
 213     // concurrently but as the result is idempotent and we don't use the class
 214     // then we do not need any synchronization beyond what is implicitly used
 215     // during class loading.
 216     if (_nest_host_index != 0) { // we have a real nest_host
 217       // Before trying to resolve check if we're in a suitable context
 218       if (!THREAD->can_call_java() && !_constants->tag_at(_nest_host_index).is_klass()) {
 219         if (log_is_enabled(Trace, class, nestmates)) {
 220           ResourceMark rm(THREAD);
 221           log_trace(class, nestmates)("Rejected resolution of nest-host of %s in unsuitable thread",
 222                                       this->external_name());
 223         }
 224         return NULL;
 225       }
 226 
 227       if (log_is_enabled(Trace, class, nestmates)) {
 228         ResourceMark rm(THREAD);
 229         log_trace(class, nestmates)("Resolving nest-host of %s using cp entry for %s",
 230                                     this->external_name(),
 231                                     _constants->klass_name_at(_nest_host_index)->as_C_string());
 232       }
 233 
 234       Klass* k = _constants->klass_at(_nest_host_index, THREAD);
 235       if (HAS_PENDING_EXCEPTION) {
 236         Handle exc_h = Handle(THREAD, PENDING_EXCEPTION);
 237         if (exc_h->is_a(SystemDictionary::NoClassDefFoundError_klass())) {
 238           // throw a new CDNFE with the original as its cause, and a clear msg
 239           ResourceMark rm(THREAD);
 240           char buf[200];
 241           CLEAR_PENDING_EXCEPTION;
 242           jio_snprintf(buf, sizeof(buf),
 243                        "Unable to load nest-host class (%s) of %s",
 244                        _constants->klass_name_at(_nest_host_index)->as_C_string(),
 245                        this->external_name());
 246           log_trace(class, nestmates)("%s - NoClassDefFoundError", buf);
 247           THROW_MSG_CAUSE_NULL(vmSymbols::java_lang_NoClassDefFoundError(), buf, exc_h);
 248         }
 249         // All other exceptions pass through (OOME, StackOverflowError, LinkageErrors etc).
 250         return NULL;
 251       }
 252 
 253       // A valid nest-host is an instance class in the current package that lists this
 254       // class as a nest member. If any of these conditions are not met we post the
 255       // requested exception type (if any) and return NULL
 256 
 257       const char* error = NULL;
 258 
 259       // JVMS 5.4.4 indicates package check comes first
 260       if (is_same_class_package(k)) {
 261 
 262         // Now check actual membership. We can't be a member if our "host" is
 263         // not an instance class.
 264         if (k->is_instance_klass()) {
 265           nest_host_k = InstanceKlass::cast(k);
 266 
 267           bool is_member = nest_host_k->has_nest_member(this, CHECK_NULL);
 268           if (is_member) {
 269             // save resolved nest-host value
 270             _nest_host = nest_host_k;
 271 
 272             if (log_is_enabled(Trace, class, nestmates)) {
 273               ResourceMark rm(THREAD);
 274               log_trace(class, nestmates)("Resolved nest-host of %s to %s",
 275                                           this->external_name(), k->external_name());
 276             }
 277             return nest_host_k;
 278           }
 279         }
 280         error = "current type is not listed as a nest member";
 281       } else {
 282         error = "types are in different packages";
 283       }
 284 
 285       if (log_is_enabled(Trace, class, nestmates)) {
 286         ResourceMark rm(THREAD);
 287         log_trace(class, nestmates)("Type %s is not a nest member of resolved type %s: %s",
 288                                     this->external_name(),
 289                                     k->external_name(),
 290                                     error);
 291       }
 292 
 293       if (validationException != NULL) {
 294         ResourceMark rm(THREAD);
 295         Exceptions::fthrow(THREAD_AND_LOCATION,
 296                            validationException,
 297                            "Type %s is not a nest member of %s: %s",
 298                            this->external_name(),
 299                            k->external_name(),
 300                            error
 301                            );
 302       }
 303       return NULL;
 304     } else {
 305       if (log_is_enabled(Trace, class, nestmates)) {
 306         ResourceMark rm(THREAD);
 307         log_trace(class, nestmates)("Type %s is not part of a nest: setting nest-host to self",
 308                                     this->external_name());
 309       }
 310       // save resolved nest-host value
 311       return (_nest_host = this);
 312     }
 313   }
 314   return nest_host_k;
 315 }
 316 
 317 // check if 'this' and k are nestmates (same nest_host), or k is our nest_host,
 318 // or we are k's nest_host - all of which is covered by comparing the two
 319 // resolved_nest_hosts
 320 bool InstanceKlass::has_nestmate_access_to(InstanceKlass* k, TRAPS) {
 321 
 322   assert(this != k, "this should be handled by higher-level code");
 323 
 324   // Per JVMS 5.4.4 we first resolve and validate the current class, then
 325   // the target class k. Resolution exceptions will be passed on by upper
 326   // layers. IncompatibleClassChangeErrors from membership validation failures
 327   // will also be passed through.
 328 
 329   Symbol* icce = vmSymbols::java_lang_IncompatibleClassChangeError();
 330   InstanceKlass* cur_host = nest_host(icce, CHECK_false);
 331   if (cur_host == NULL) {
 332     return false;
 333   }
 334 
 335   Klass* k_nest_host = k->nest_host(icce, CHECK_false);
 336   if (k_nest_host == NULL) {
 337     return false;
 338   }
 339 
 340   bool access = (cur_host == k_nest_host);
 341 
 342   if (log_is_enabled(Trace, class, nestmates)) {
 343     ResourceMark rm(THREAD);
 344     log_trace(class, nestmates)("Class %s does %shave nestmate access to %s",
 345                                 this->external_name(),
 346                                 access ? "" : "NOT ",
 347                                 k->external_name());
 348   }
 349 
 350   return access;
 351 }
 352 
 353 InstanceKlass* InstanceKlass::allocate_instance_klass(const ClassFileParser& parser, TRAPS) {
 354   const int size = InstanceKlass::size(parser.vtable_size(),
 355                                        parser.itable_size(),
 356                                        nonstatic_oop_map_size(parser.total_oop_map_count()),
 357                                        parser.is_interface(),
 358                                        parser.is_unsafe_anonymous(),
 359                                        should_store_fingerprint(parser.is_unsafe_anonymous()));
 360 
 361   const Symbol* const class_name = parser.class_name();
 362   assert(class_name != NULL, "invariant");
 363   ClassLoaderData* loader_data = parser.loader_data();
 364   assert(loader_data != NULL, "invariant");
 365 
 366   InstanceKlass* ik;
 367 
 368   // Allocation
 369   if (REF_NONE == parser.reference_type()) {
 370     if (class_name == vmSymbols::java_lang_Class()) {
 371       // mirror
 372       ik = new (loader_data, size, THREAD) InstanceMirrorKlass(parser);
 373     }
 374     else if (is_class_loader(class_name, parser)) {
 375       // class loader
 376       ik = new (loader_data, size, THREAD) InstanceClassLoaderKlass(parser);
 377     } else {
 378       // normal
 379       ik = new (loader_data, size, THREAD) InstanceKlass(parser, InstanceKlass::_misc_kind_other);
 380     }
 381   } else {
 382     // reference
 383     ik = new (loader_data, size, THREAD) InstanceRefKlass(parser);
 384   }
 385 
 386   // Check for pending exception before adding to the loader data and incrementing
 387   // class count.  Can get OOM here.
 388   if (HAS_PENDING_EXCEPTION) {
 389     return NULL;
 390   }
 391 
 392   return ik;
 393 }
 394 
 395 
 396 // copy method ordering from resource area to Metaspace
 397 void InstanceKlass::copy_method_ordering(const intArray* m, TRAPS) {
 398   if (m != NULL) {
 399     // allocate a new array and copy contents (memcpy?)
 400     _method_ordering = MetadataFactory::new_array<int>(class_loader_data(), m->length(), CHECK);
 401     for (int i = 0; i < m->length(); i++) {
 402       _method_ordering->at_put(i, m->at(i));
 403     }
 404   } else {
 405     _method_ordering = Universe::the_empty_int_array();
 406   }
 407 }
 408 
 409 // create a new array of vtable_indices for default methods
 410 Array<int>* InstanceKlass::create_new_default_vtable_indices(int len, TRAPS) {
 411   Array<int>* vtable_indices = MetadataFactory::new_array<int>(class_loader_data(), len, CHECK_NULL);
 412   assert(default_vtable_indices() == NULL, "only create once");
 413   set_default_vtable_indices(vtable_indices);
 414   return vtable_indices;
 415 }
 416 
 417 InstanceKlass::InstanceKlass(const ClassFileParser& parser, unsigned kind, KlassID id) :
 418   Klass(id),
 419   _nest_members(NULL),
 420   _nest_host_index(0),
 421   _nest_host(NULL),
 422   _static_field_size(parser.static_field_size()),
 423   _nonstatic_oop_map_size(nonstatic_oop_map_size(parser.total_oop_map_count())),
 424   _itable_len(parser.itable_size()),
 425   _reference_type(parser.reference_type())
 426 {
 427   set_vtable_length(parser.vtable_size());
 428   set_kind(kind);
 429   set_access_flags(parser.access_flags());
 430   set_is_unsafe_anonymous(parser.is_unsafe_anonymous());
 431   set_layout_helper(Klass::instance_layout_helper(parser.layout_size(),
 432                                                     false));
 433 
 434   assert(NULL == _methods, "underlying memory not zeroed?");
 435   assert(is_instance_klass(), "is layout incorrect?");
 436   assert(size_helper() == parser.layout_size(), "incorrect size_helper?");
 437 
 438   if (DumpSharedSpaces) {
 439     SystemDictionaryShared::init_dumptime_info(this);
 440   }
 441 }
 442 
 443 void InstanceKlass::deallocate_methods(ClassLoaderData* loader_data,
 444                                        Array<Method*>* methods) {
 445   if (methods != NULL && methods != Universe::the_empty_method_array() &&
 446       !methods->is_shared()) {
 447     for (int i = 0; i < methods->length(); i++) {
 448       Method* method = methods->at(i);
 449       if (method == NULL) continue;  // maybe null if error processing
 450       // Only want to delete methods that are not executing for RedefineClasses.
 451       // The previous version will point to them so they're not totally dangling
 452       assert (!method->on_stack(), "shouldn't be called with methods on stack");
 453       MetadataFactory::free_metadata(loader_data, method);
 454     }
 455     MetadataFactory::free_array<Method*>(loader_data, methods);
 456   }
 457 }
 458 
 459 void InstanceKlass::deallocate_interfaces(ClassLoaderData* loader_data,
 460                                           const Klass* super_klass,
 461                                           Array<InstanceKlass*>* local_interfaces,
 462                                           Array<InstanceKlass*>* transitive_interfaces) {
 463   // Only deallocate transitive interfaces if not empty, same as super class
 464   // or same as local interfaces.  See code in parseClassFile.
 465   Array<InstanceKlass*>* ti = transitive_interfaces;
 466   if (ti != Universe::the_empty_instance_klass_array() && ti != local_interfaces) {
 467     // check that the interfaces don't come from super class
 468     Array<InstanceKlass*>* sti = (super_klass == NULL) ? NULL :
 469                     InstanceKlass::cast(super_klass)->transitive_interfaces();
 470     if (ti != sti && ti != NULL && !ti->is_shared()) {
 471       MetadataFactory::free_array<InstanceKlass*>(loader_data, ti);
 472     }
 473   }
 474 
 475   // local interfaces can be empty
 476   if (local_interfaces != Universe::the_empty_instance_klass_array() &&
 477       local_interfaces != NULL && !local_interfaces->is_shared()) {
 478     MetadataFactory::free_array<InstanceKlass*>(loader_data, local_interfaces);
 479   }
 480 }
 481 
 482 // This function deallocates the metadata and C heap pointers that the
 483 // InstanceKlass points to.
 484 void InstanceKlass::deallocate_contents(ClassLoaderData* loader_data) {
 485 
 486   // Orphan the mirror first, CMS thinks it's still live.
 487   if (java_mirror() != NULL) {
 488     java_lang_Class::set_klass(java_mirror(), NULL);
 489   }
 490 
 491   // Also remove mirror from handles
 492   loader_data->remove_handle(_java_mirror);
 493 
 494   // Need to take this class off the class loader data list.
 495   loader_data->remove_class(this);
 496 
 497   // The array_klass for this class is created later, after error handling.
 498   // For class redefinition, we keep the original class so this scratch class
 499   // doesn't have an array class.  Either way, assert that there is nothing
 500   // to deallocate.
 501   assert(array_klasses() == NULL, "array classes shouldn't be created for this class yet");
 502 
 503   // Release C heap allocated data that this might point to, which includes
 504   // reference counting symbol names.
 505   release_C_heap_structures();
 506 
 507   deallocate_methods(loader_data, methods());
 508   set_methods(NULL);
 509 
 510   if (method_ordering() != NULL &&
 511       method_ordering() != Universe::the_empty_int_array() &&
 512       !method_ordering()->is_shared()) {
 513     MetadataFactory::free_array<int>(loader_data, method_ordering());
 514   }
 515   set_method_ordering(NULL);
 516 
 517   // default methods can be empty
 518   if (default_methods() != NULL &&
 519       default_methods() != Universe::the_empty_method_array() &&
 520       !default_methods()->is_shared()) {
 521     MetadataFactory::free_array<Method*>(loader_data, default_methods());
 522   }
 523   // Do NOT deallocate the default methods, they are owned by superinterfaces.
 524   set_default_methods(NULL);
 525 
 526   // default methods vtable indices can be empty
 527   if (default_vtable_indices() != NULL &&
 528       !default_vtable_indices()->is_shared()) {
 529     MetadataFactory::free_array<int>(loader_data, default_vtable_indices());
 530   }
 531   set_default_vtable_indices(NULL);
 532 
 533 
 534   // This array is in Klass, but remove it with the InstanceKlass since
 535   // this place would be the only caller and it can share memory with transitive
 536   // interfaces.
 537   if (secondary_supers() != NULL &&
 538       secondary_supers() != Universe::the_empty_klass_array() &&
 539       // see comments in compute_secondary_supers about the following cast
 540       (address)(secondary_supers()) != (address)(transitive_interfaces()) &&
 541       !secondary_supers()->is_shared()) {
 542     MetadataFactory::free_array<Klass*>(loader_data, secondary_supers());
 543   }
 544   set_secondary_supers(NULL);
 545 
 546   deallocate_interfaces(loader_data, super(), local_interfaces(), transitive_interfaces());
 547   set_transitive_interfaces(NULL);
 548   set_local_interfaces(NULL);
 549 
 550   if (fields() != NULL && !fields()->is_shared()) {
 551     MetadataFactory::free_array<jushort>(loader_data, fields());
 552   }
 553   set_fields(NULL, 0);
 554 
 555   // If a method from a redefined class is using this constant pool, don't
 556   // delete it, yet.  The new class's previous version will point to this.
 557   if (constants() != NULL) {
 558     assert (!constants()->on_stack(), "shouldn't be called if anything is onstack");
 559     if (!constants()->is_shared()) {
 560       MetadataFactory::free_metadata(loader_data, constants());
 561     }
 562     // Delete any cached resolution errors for the constant pool
 563     SystemDictionary::delete_resolution_error(constants());
 564 
 565     set_constants(NULL);
 566   }
 567 
 568   if (inner_classes() != NULL &&
 569       inner_classes() != Universe::the_empty_short_array() &&
 570       !inner_classes()->is_shared()) {
 571     MetadataFactory::free_array<jushort>(loader_data, inner_classes());
 572   }
 573   set_inner_classes(NULL);
 574 
 575   if (nest_members() != NULL &&
 576       nest_members() != Universe::the_empty_short_array() &&
 577       !nest_members()->is_shared()) {
 578     MetadataFactory::free_array<jushort>(loader_data, nest_members());
 579   }
 580   set_nest_members(NULL);
 581 
 582   // We should deallocate the Annotations instance if it's not in shared spaces.
 583   if (annotations() != NULL && !annotations()->is_shared()) {
 584     MetadataFactory::free_metadata(loader_data, annotations());
 585   }
 586   set_annotations(NULL);
 587 
 588   if (DumpSharedSpaces) {
 589     SystemDictionaryShared::remove_dumptime_info(this);
 590   }
 591 }
 592 
 593 bool InstanceKlass::should_be_initialized() const {
 594   return !is_initialized();
 595 }
 596 
 597 klassItable InstanceKlass::itable() const {
 598   return klassItable(const_cast<InstanceKlass*>(this));
 599 }
 600 
 601 void InstanceKlass::eager_initialize(Thread *thread) {
 602   if (!EagerInitialization) return;
 603 
 604   if (this->is_not_initialized()) {
 605     // abort if the the class has a class initializer
 606     if (this->class_initializer() != NULL) return;
 607 
 608     // abort if it is java.lang.Object (initialization is handled in genesis)
 609     Klass* super_klass = super();
 610     if (super_klass == NULL) return;
 611 
 612     // abort if the super class should be initialized
 613     if (!InstanceKlass::cast(super_klass)->is_initialized()) return;
 614 
 615     // call body to expose the this pointer
 616     eager_initialize_impl();
 617   }
 618 }
 619 
 620 // JVMTI spec thinks there are signers and protection domain in the
 621 // instanceKlass.  These accessors pretend these fields are there.
 622 // The hprof specification also thinks these fields are in InstanceKlass.
 623 oop InstanceKlass::protection_domain() const {
 624   // return the protection_domain from the mirror
 625   return java_lang_Class::protection_domain(java_mirror());
 626 }
 627 
 628 // To remove these from requires an incompatible change and CCC request.
 629 objArrayOop InstanceKlass::signers() const {
 630   // return the signers from the mirror
 631   return java_lang_Class::signers(java_mirror());
 632 }
 633 
 634 oop InstanceKlass::init_lock() const {
 635   // return the init lock from the mirror
 636   oop lock = java_lang_Class::init_lock(java_mirror());
 637   // Prevent reordering with any access of initialization state
 638   OrderAccess::loadload();
 639   assert((oop)lock != NULL || !is_not_initialized(), // initialized or in_error state
 640          "only fully initialized state can have a null lock");
 641   return lock;
 642 }
 643 
 644 // Set the initialization lock to null so the object can be GC'ed.  Any racing
 645 // threads to get this lock will see a null lock and will not lock.
 646 // That's okay because they all check for initialized state after getting
 647 // the lock and return.
 648 void InstanceKlass::fence_and_clear_init_lock() {
 649   // make sure previous stores are all done, notably the init_state.
 650   OrderAccess::storestore();
 651   java_lang_Class::set_init_lock(java_mirror(), NULL);
 652   assert(!is_not_initialized(), "class must be initialized now");
 653 }
 654 
 655 void InstanceKlass::eager_initialize_impl() {
 656   EXCEPTION_MARK;
 657   HandleMark hm(THREAD);
 658   Handle h_init_lock(THREAD, init_lock());
 659   ObjectLocker ol(h_init_lock, THREAD, h_init_lock() != NULL);
 660 
 661   // abort if someone beat us to the initialization
 662   if (!is_not_initialized()) return;  // note: not equivalent to is_initialized()
 663 
 664   ClassState old_state = init_state();
 665   link_class_impl(THREAD);
 666   if (HAS_PENDING_EXCEPTION) {
 667     CLEAR_PENDING_EXCEPTION;
 668     // Abort if linking the class throws an exception.
 669 
 670     // Use a test to avoid redundantly resetting the state if there's
 671     // no change.  Set_init_state() asserts that state changes make
 672     // progress, whereas here we might just be spinning in place.
 673     if (old_state != _init_state)
 674       set_init_state(old_state);
 675   } else {
 676     // linking successfull, mark class as initialized
 677     set_init_state(fully_initialized);
 678     fence_and_clear_init_lock();
 679     // trace
 680     if (log_is_enabled(Info, class, init)) {
 681       ResourceMark rm(THREAD);
 682       log_info(class, init)("[Initialized %s without side effects]", external_name());
 683     }
 684   }
 685 }
 686 
 687 
 688 // See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization
 689 // process. The step comments refers to the procedure described in that section.
 690 // Note: implementation moved to static method to expose the this pointer.
 691 void InstanceKlass::initialize(TRAPS) {
 692   if (this->should_be_initialized()) {
 693     initialize_impl(CHECK);
 694     // Note: at this point the class may be initialized
 695     //       OR it may be in the state of being initialized
 696     //       in case of recursive initialization!
 697   } else {
 698     assert(is_initialized(), "sanity check");
 699   }
 700 }
 701 
 702 
 703 bool InstanceKlass::verify_code(TRAPS) {
 704   // 1) Verify the bytecodes
 705   return Verifier::verify(this, should_verify_class(), THREAD);
 706 }
 707 
 708 void InstanceKlass::link_class(TRAPS) {
 709   assert(is_loaded(), "must be loaded");
 710   if (!is_linked()) {
 711     link_class_impl(CHECK);
 712   }
 713 }
 714 
 715 // Called to verify that a class can link during initialization, without
 716 // throwing a VerifyError.
 717 bool InstanceKlass::link_class_or_fail(TRAPS) {
 718   assert(is_loaded(), "must be loaded");
 719   if (!is_linked()) {
 720     link_class_impl(CHECK_false);
 721   }
 722   return is_linked();
 723 }
 724 
 725 bool InstanceKlass::link_class_impl(TRAPS) {
 726   if (DumpSharedSpaces && is_in_error_state()) {
 727     // This is for CDS dumping phase only -- we use the in_error_state to indicate that
 728     // the class has failed verification. Throwing the NoClassDefFoundError here is just
 729     // a convenient way to stop repeat attempts to verify the same (bad) class.
 730     //
 731     // Note that the NoClassDefFoundError is not part of the JLS, and should not be thrown
 732     // if we are executing Java code. This is not a problem for CDS dumping phase since
 733     // it doesn't execute any Java code.
 734     ResourceMark rm(THREAD);
 735     Exceptions::fthrow(THREAD_AND_LOCATION,
 736                        vmSymbols::java_lang_NoClassDefFoundError(),
 737                        "Class %s, or one of its supertypes, failed class initialization",
 738                        external_name());
 739     return false;
 740   }
 741   // return if already verified
 742   if (is_linked()) {
 743     return true;
 744   }
 745 
 746   // Timing
 747   // timer handles recursion
 748   assert(THREAD->is_Java_thread(), "non-JavaThread in link_class_impl");
 749   JavaThread* jt = (JavaThread*)THREAD;
 750 
 751   // link super class before linking this class
 752   Klass* super_klass = super();
 753   if (super_klass != NULL) {
 754     if (super_klass->is_interface()) {  // check if super class is an interface
 755       ResourceMark rm(THREAD);
 756       Exceptions::fthrow(
 757         THREAD_AND_LOCATION,
 758         vmSymbols::java_lang_IncompatibleClassChangeError(),
 759         "class %s has interface %s as super class",
 760         external_name(),
 761         super_klass->external_name()
 762       );
 763       return false;
 764     }
 765 
 766     InstanceKlass* ik_super = InstanceKlass::cast(super_klass);
 767     ik_super->link_class_impl(CHECK_false);
 768   }
 769 
 770   // link all interfaces implemented by this class before linking this class
 771   Array<InstanceKlass*>* interfaces = local_interfaces();
 772   int num_interfaces = interfaces->length();
 773   for (int index = 0; index < num_interfaces; index++) {
 774     InstanceKlass* interk = interfaces->at(index);
 775     interk->link_class_impl(CHECK_false);
 776   }
 777 
 778   // in case the class is linked in the process of linking its superclasses
 779   if (is_linked()) {
 780     return true;
 781   }
 782 
 783   // trace only the link time for this klass that includes
 784   // the verification time
 785   PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(),
 786                              ClassLoader::perf_class_link_selftime(),
 787                              ClassLoader::perf_classes_linked(),
 788                              jt->get_thread_stat()->perf_recursion_counts_addr(),
 789                              jt->get_thread_stat()->perf_timers_addr(),
 790                              PerfClassTraceTime::CLASS_LINK);
 791 
 792   // verification & rewriting
 793   {
 794     HandleMark hm(THREAD);
 795     Handle h_init_lock(THREAD, init_lock());
 796     ObjectLocker ol(h_init_lock, THREAD, h_init_lock() != NULL);
 797     // rewritten will have been set if loader constraint error found
 798     // on an earlier link attempt
 799     // don't verify or rewrite if already rewritten
 800     //
 801 
 802     if (!is_linked()) {
 803       if (!is_rewritten()) {
 804         {
 805           bool verify_ok = verify_code(THREAD);
 806           if (!verify_ok) {
 807             return false;
 808           }
 809         }
 810 
 811         // Just in case a side-effect of verify linked this class already
 812         // (which can sometimes happen since the verifier loads classes
 813         // using custom class loaders, which are free to initialize things)
 814         if (is_linked()) {
 815           return true;
 816         }
 817 
 818         // also sets rewritten
 819         rewrite_class(CHECK_false);
 820       } else if (is_shared()) {
 821         SystemDictionaryShared::check_verification_constraints(this, CHECK_false);
 822       }
 823 
 824       // relocate jsrs and link methods after they are all rewritten
 825       link_methods(CHECK_false);
 826 
 827       // Initialize the vtable and interface table after
 828       // methods have been rewritten since rewrite may
 829       // fabricate new Method*s.
 830       // also does loader constraint checking
 831       //
 832       // initialize_vtable and initialize_itable need to be rerun for
 833       // a shared class if the class is not loaded by the NULL classloader.
 834       ClassLoaderData * loader_data = class_loader_data();
 835       if (!(is_shared() &&
 836             loader_data->is_the_null_class_loader_data())) {
 837         vtable().initialize_vtable(true, CHECK_false);
 838         itable().initialize_itable(true, CHECK_false);
 839       }
 840 #ifdef ASSERT
 841       else {
 842         vtable().verify(tty, true);
 843         // In case itable verification is ever added.
 844         // itable().verify(tty, true);
 845       }
 846 #endif
 847       set_init_state(linked);
 848       if (JvmtiExport::should_post_class_prepare()) {
 849         Thread *thread = THREAD;
 850         assert(thread->is_Java_thread(), "thread->is_Java_thread()");
 851         JvmtiExport::post_class_prepare((JavaThread *) thread, this);
 852       }
 853     }
 854   }
 855   return true;
 856 }
 857 
 858 // Rewrite the byte codes of all of the methods of a class.
 859 // The rewriter must be called exactly once. Rewriting must happen after
 860 // verification but before the first method of the class is executed.
 861 void InstanceKlass::rewrite_class(TRAPS) {
 862   assert(is_loaded(), "must be loaded");
 863   if (is_rewritten()) {
 864     assert(is_shared(), "rewriting an unshared class?");
 865     return;
 866   }
 867   Rewriter::rewrite(this, CHECK);
 868   set_rewritten();
 869 }
 870 
 871 // Now relocate and link method entry points after class is rewritten.
 872 // This is outside is_rewritten flag. In case of an exception, it can be
 873 // executed more than once.
 874 void InstanceKlass::link_methods(TRAPS) {
 875   int len = methods()->length();
 876   for (int i = len-1; i >= 0; i--) {
 877     methodHandle m(THREAD, methods()->at(i));
 878 
 879     // Set up method entry points for compiler and interpreter    .
 880     m->link_method(m, CHECK);
 881   }
 882 }
 883 
 884 // Eagerly initialize superinterfaces that declare default methods (concrete instance: any access)
 885 void InstanceKlass::initialize_super_interfaces(TRAPS) {
 886   assert (has_nonstatic_concrete_methods(), "caller should have checked this");
 887   for (int i = 0; i < local_interfaces()->length(); ++i) {
 888     InstanceKlass* ik = local_interfaces()->at(i);
 889 
 890     // Initialization is depth first search ie. we start with top of the inheritance tree
 891     // has_nonstatic_concrete_methods drives searching superinterfaces since it
 892     // means has_nonstatic_concrete_methods in its superinterface hierarchy
 893     if (ik->has_nonstatic_concrete_methods()) {
 894       ik->initialize_super_interfaces(CHECK);
 895     }
 896 
 897     // Only initialize() interfaces that "declare" concrete methods.
 898     if (ik->should_be_initialized() && ik->declares_nonstatic_concrete_methods()) {
 899       ik->initialize(CHECK);
 900     }
 901   }
 902 }
 903 
 904 void InstanceKlass::initialize_impl(TRAPS) {
 905   HandleMark hm(THREAD);
 906 
 907   // Make sure klass is linked (verified) before initialization
 908   // A class could already be verified, since it has been reflected upon.
 909   link_class(CHECK);
 910 
 911   DTRACE_CLASSINIT_PROBE(required, -1);
 912 
 913   bool wait = false;
 914 
 915   // refer to the JVM book page 47 for description of steps
 916   // Step 1
 917   {
 918     Handle h_init_lock(THREAD, init_lock());
 919     ObjectLocker ol(h_init_lock, THREAD, h_init_lock() != NULL);
 920 
 921     Thread *self = THREAD; // it's passed the current thread
 922 
 923     // Step 2
 924     // If we were to use wait() instead of waitInterruptibly() then
 925     // we might end up throwing IE from link/symbol resolution sites
 926     // that aren't expected to throw.  This would wreak havoc.  See 6320309.
 927     while(is_being_initialized() && !is_reentrant_initialization(self)) {
 928         wait = true;
 929       ol.waitUninterruptibly(CHECK);
 930     }
 931 
 932     // Step 3
 933     if (is_being_initialized() && is_reentrant_initialization(self)) {
 934       DTRACE_CLASSINIT_PROBE_WAIT(recursive, -1, wait);
 935       return;
 936     }
 937 
 938     // Step 4
 939     if (is_initialized()) {
 940       DTRACE_CLASSINIT_PROBE_WAIT(concurrent, -1, wait);
 941       return;
 942     }
 943 
 944     // Step 5
 945     if (is_in_error_state()) {
 946       DTRACE_CLASSINIT_PROBE_WAIT(erroneous, -1, wait);
 947       ResourceMark rm(THREAD);
 948       const char* desc = "Could not initialize class ";
 949       const char* className = external_name();
 950       size_t msglen = strlen(desc) + strlen(className) + 1;
 951       char* message = NEW_RESOURCE_ARRAY(char, msglen);
 952       if (NULL == message) {
 953         // Out of memory: can't create detailed error message
 954           THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), className);
 955       } else {
 956         jio_snprintf(message, msglen, "%s%s", desc, className);
 957           THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), message);
 958       }
 959     }
 960 
 961     // Step 6
 962     set_init_state(being_initialized);
 963     set_init_thread(self);
 964   }
 965 
 966   // Step 7
 967   // Next, if C is a class rather than an interface, initialize it's super class and super
 968   // interfaces.
 969   if (!is_interface()) {
 970     Klass* super_klass = super();
 971     if (super_klass != NULL && super_klass->should_be_initialized()) {
 972       super_klass->initialize(THREAD);
 973     }
 974     // If C implements any interface that declares a non-static, concrete method,
 975     // the initialization of C triggers initialization of its super interfaces.
 976     // Only need to recurse if has_nonstatic_concrete_methods which includes declaring and
 977     // having a superinterface that declares, non-static, concrete methods
 978     if (!HAS_PENDING_EXCEPTION && has_nonstatic_concrete_methods()) {
 979       initialize_super_interfaces(THREAD);
 980     }
 981 
 982     // If any exceptions, complete abruptly, throwing the same exception as above.
 983     if (HAS_PENDING_EXCEPTION) {
 984       Handle e(THREAD, PENDING_EXCEPTION);
 985       CLEAR_PENDING_EXCEPTION;
 986       {
 987         EXCEPTION_MARK;
 988         // Locks object, set state, and notify all waiting threads
 989         set_initialization_state_and_notify(initialization_error, THREAD);
 990         CLEAR_PENDING_EXCEPTION;
 991       }
 992       DTRACE_CLASSINIT_PROBE_WAIT(super__failed, -1, wait);
 993       THROW_OOP(e());
 994     }
 995   }
 996 
 997 
 998   // Look for aot compiled methods for this klass, including class initializer.
 999   AOTLoader::load_for_klass(this, THREAD);
1000 
1001   // Step 8
1002   {
1003     assert(THREAD->is_Java_thread(), "non-JavaThread in initialize_impl");
1004     JavaThread* jt = (JavaThread*)THREAD;
1005     DTRACE_CLASSINIT_PROBE_WAIT(clinit, -1, wait);
1006     // Timer includes any side effects of class initialization (resolution,
1007     // etc), but not recursive entry into call_class_initializer().
1008     PerfClassTraceTime timer(ClassLoader::perf_class_init_time(),
1009                              ClassLoader::perf_class_init_selftime(),
1010                              ClassLoader::perf_classes_inited(),
1011                              jt->get_thread_stat()->perf_recursion_counts_addr(),
1012                              jt->get_thread_stat()->perf_timers_addr(),
1013                              PerfClassTraceTime::CLASS_CLINIT);
1014     call_class_initializer(THREAD);
1015   }
1016 
1017   // Step 9
1018   if (!HAS_PENDING_EXCEPTION) {
1019     set_initialization_state_and_notify(fully_initialized, CHECK);
1020     {
1021       debug_only(vtable().verify(tty, true);)
1022     }
1023   }
1024   else {
1025     // Step 10 and 11
1026     Handle e(THREAD, PENDING_EXCEPTION);
1027     CLEAR_PENDING_EXCEPTION;
1028     // JVMTI has already reported the pending exception
1029     // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
1030     JvmtiExport::clear_detected_exception((JavaThread*)THREAD);
1031     {
1032       EXCEPTION_MARK;
1033       set_initialization_state_and_notify(initialization_error, THREAD);
1034       CLEAR_PENDING_EXCEPTION;   // ignore any exception thrown, class initialization error is thrown below
1035       // JVMTI has already reported the pending exception
1036       // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
1037       JvmtiExport::clear_detected_exception((JavaThread*)THREAD);
1038     }
1039     DTRACE_CLASSINIT_PROBE_WAIT(error, -1, wait);
1040     if (e->is_a(SystemDictionary::Error_klass())) {
1041       THROW_OOP(e());
1042     } else {
1043       JavaCallArguments args(e);
1044       THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(),
1045                 vmSymbols::throwable_void_signature(),
1046                 &args);
1047     }
1048   }
1049   DTRACE_CLASSINIT_PROBE_WAIT(end, -1, wait);
1050 }
1051 
1052 
1053 void InstanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) {
1054   Handle h_init_lock(THREAD, init_lock());
1055   if (h_init_lock() != NULL) {
1056     ObjectLocker ol(h_init_lock, THREAD);
1057     set_init_state(state);
1058     fence_and_clear_init_lock();
1059     ol.notify_all(CHECK);
1060   } else {
1061     assert(h_init_lock() != NULL, "The initialization state should never be set twice");
1062     set_init_state(state);
1063   }
1064 }
1065 
1066 Klass* InstanceKlass::implementor() const {
1067   assert_locked_or_safepoint(Compile_lock);
1068   Klass** k = adr_implementor();
1069   if (k == NULL) {
1070     return NULL;
1071   } else {
1072     return *k;
1073   }
1074 }
1075 
1076 void InstanceKlass::set_implementor(Klass* k) {
1077   assert_lock_strong(Compile_lock);
1078   assert(is_interface(), "not interface");
1079   Klass** addr = adr_implementor();
1080   assert(addr != NULL, "null addr");
1081   if (addr != NULL) {
1082     *addr = k;
1083   }
1084 }
1085 
1086 int  InstanceKlass::nof_implementors() const {
1087   assert_lock_strong(Compile_lock);
1088   Klass* k = implementor();
1089   if (k == NULL) {
1090     return 0;
1091   } else if (k != this) {
1092     return 1;
1093   } else {
1094     return 2;
1095   }
1096 }
1097 
1098 // The embedded _implementor field can only record one implementor.
1099 // When there are more than one implementors, the _implementor field
1100 // is set to the interface Klass* itself. Following are the possible
1101 // values for the _implementor field:
1102 //   NULL                  - no implementor
1103 //   implementor Klass*    - one implementor
1104 //   self                  - more than one implementor
1105 //
1106 // The _implementor field only exists for interfaces.
1107 void InstanceKlass::add_implementor(Klass* k) {
1108   assert_lock_strong(Compile_lock);
1109   assert(is_interface(), "not interface");
1110   // Filter out my subinterfaces.
1111   // (Note: Interfaces are never on the subklass list.)
1112   if (InstanceKlass::cast(k)->is_interface()) return;
1113 
1114   // Filter out subclasses whose supers already implement me.
1115   // (Note: CHA must walk subclasses of direct implementors
1116   // in order to locate indirect implementors.)
1117   Klass* sk = k->super();
1118   if (sk != NULL && InstanceKlass::cast(sk)->implements_interface(this))
1119     // We only need to check one immediate superclass, since the
1120     // implements_interface query looks at transitive_interfaces.
1121     // Any supers of the super have the same (or fewer) transitive_interfaces.
1122     return;
1123 
1124   Klass* ik = implementor();
1125   if (ik == NULL) {
1126     set_implementor(k);
1127   } else if (ik != this) {
1128     // There is already an implementor. Use itself as an indicator of
1129     // more than one implementors.
1130     set_implementor(this);
1131   }
1132 
1133   // The implementor also implements the transitive_interfaces
1134   for (int index = 0; index < local_interfaces()->length(); index++) {
1135     InstanceKlass::cast(local_interfaces()->at(index))->add_implementor(k);
1136   }
1137 }
1138 
1139 void InstanceKlass::init_implementor() {
1140   if (is_interface()) {
1141     set_implementor(NULL);
1142   }
1143 }
1144 
1145 
1146 void InstanceKlass::process_interfaces(Thread *thread) {
1147   // link this class into the implementors list of every interface it implements
1148   for (int i = local_interfaces()->length() - 1; i >= 0; i--) {
1149     assert(local_interfaces()->at(i)->is_klass(), "must be a klass");
1150     InstanceKlass* interf = InstanceKlass::cast(local_interfaces()->at(i));
1151     assert(interf->is_interface(), "expected interface");
1152     interf->add_implementor(this);
1153   }
1154 }
1155 
1156 bool InstanceKlass::can_be_primary_super_slow() const {
1157   if (is_interface())
1158     return false;
1159   else
1160     return Klass::can_be_primary_super_slow();
1161 }
1162 
1163 GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots,
1164                                                                Array<InstanceKlass*>* transitive_interfaces) {
1165   // The secondaries are the implemented interfaces.
1166   Array<InstanceKlass*>* interfaces = transitive_interfaces;
1167   int num_secondaries = num_extra_slots + interfaces->length();
1168   if (num_secondaries == 0) {
1169     // Must share this for correct bootstrapping!
1170     set_secondary_supers(Universe::the_empty_klass_array());
1171     return NULL;
1172   } else if (num_extra_slots == 0) {
1173     // The secondary super list is exactly the same as the transitive interfaces, so
1174     // let's use it instead of making a copy.
1175     // Redefine classes has to be careful not to delete this!
1176     // We need the cast because Array<Klass*> is NOT a supertype of Array<InstanceKlass*>,
1177     // (but it's safe to do here because we won't write into _secondary_supers from this point on).
1178     set_secondary_supers((Array<Klass*>*)(address)interfaces);
1179     return NULL;
1180   } else {
1181     // Copy transitive interfaces to a temporary growable array to be constructed
1182     // into the secondary super list with extra slots.
1183     GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length());
1184     for (int i = 0; i < interfaces->length(); i++) {
1185       secondaries->push(interfaces->at(i));
1186     }
1187     return secondaries;
1188   }
1189 }
1190 
1191 bool InstanceKlass::compute_is_subtype_of(Klass* k) {
1192   if (k->is_interface()) {
1193     return implements_interface(k);
1194   } else {
1195     return Klass::compute_is_subtype_of(k);
1196   }
1197 }
1198 
1199 bool InstanceKlass::implements_interface(Klass* k) const {
1200   if (this == k) return true;
1201   assert(k->is_interface(), "should be an interface class");
1202   for (int i = 0; i < transitive_interfaces()->length(); i++) {
1203     if (transitive_interfaces()->at(i) == k) {
1204       return true;
1205     }
1206   }
1207   return false;
1208 }
1209 
1210 bool InstanceKlass::is_same_or_direct_interface(Klass *k) const {
1211   // Verify direct super interface
1212   if (this == k) return true;
1213   assert(k->is_interface(), "should be an interface class");
1214   for (int i = 0; i < local_interfaces()->length(); i++) {
1215     if (local_interfaces()->at(i) == k) {
1216       return true;
1217     }
1218   }
1219   return false;
1220 }
1221 
1222 objArrayOop InstanceKlass::allocate_objArray(int n, int length, TRAPS) {
1223   check_array_allocation_length(length, arrayOopDesc::max_array_length(T_OBJECT), CHECK_NULL);
1224   int size = objArrayOopDesc::object_size(length);
1225   Klass* ak = array_klass(n, CHECK_NULL);
1226   objArrayOop o = (objArrayOop)Universe::heap()->array_allocate(ak, size, length,
1227                                                                 /* do_zero */ true, CHECK_NULL);
1228   return o;
1229 }
1230 
1231 instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) {
1232   if (TraceFinalizerRegistration) {
1233     tty->print("Registered ");
1234     i->print_value_on(tty);
1235     tty->print_cr(" (" INTPTR_FORMAT ") as finalizable", p2i(i));
1236   }
1237   instanceHandle h_i(THREAD, i);
1238   // Pass the handle as argument, JavaCalls::call expects oop as jobjects
1239   JavaValue result(T_VOID);
1240   JavaCallArguments args(h_i);
1241   methodHandle mh (THREAD, Universe::finalizer_register_method());
1242   JavaCalls::call(&result, mh, &args, CHECK_NULL);
1243   return h_i();
1244 }
1245 
1246 instanceOop InstanceKlass::allocate_instance(TRAPS) {
1247   bool has_finalizer_flag = has_finalizer(); // Query before possible GC
1248   int size = size_helper();  // Query before forming handle.
1249 
1250   instanceOop i;
1251 
1252   i = (instanceOop)Universe::heap()->obj_allocate(this, size, CHECK_NULL);
1253   if (has_finalizer_flag && !RegisterFinalizersAtInit) {
1254     i = register_finalizer(i, CHECK_NULL);
1255   }
1256   return i;
1257 }
1258 
1259 instanceHandle InstanceKlass::allocate_instance_handle(TRAPS) {
1260   return instanceHandle(THREAD, allocate_instance(THREAD));
1261 }
1262 
1263 void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) {
1264   if (is_interface() || is_abstract()) {
1265     ResourceMark rm(THREAD);
1266     THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
1267               : vmSymbols::java_lang_InstantiationException(), external_name());
1268   }
1269   if (this == SystemDictionary::Class_klass()) {
1270     ResourceMark rm(THREAD);
1271     THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError()
1272               : vmSymbols::java_lang_IllegalAccessException(), external_name());
1273   }
1274 }
1275 
1276 Klass* InstanceKlass::array_klass_impl(bool or_null, int n, TRAPS) {
1277   // Need load-acquire for lock-free read
1278   if (array_klasses_acquire() == NULL) {
1279     if (or_null) return NULL;
1280 
1281     ResourceMark rm;
1282     JavaThread *jt = (JavaThread *)THREAD;
1283     {
1284       // Atomic creation of array_klasses
1285       MutexLocker ma(MultiArray_lock, THREAD);
1286 
1287       // Check if update has already taken place
1288       if (array_klasses() == NULL) {
1289         Klass*    k = ObjArrayKlass::allocate_objArray_klass(class_loader_data(), 1, this, CHECK_NULL);
1290         // use 'release' to pair with lock-free load
1291         release_set_array_klasses(k);
1292       }
1293     }
1294   }
1295   // _this will always be set at this point
1296   ObjArrayKlass* oak = (ObjArrayKlass*)array_klasses();
1297   if (or_null) {
1298     return oak->array_klass_or_null(n);
1299   }
1300   return oak->array_klass(n, THREAD);
1301 }
1302 
1303 Klass* InstanceKlass::array_klass_impl(bool or_null, TRAPS) {
1304   return array_klass_impl(or_null, 1, THREAD);
1305 }
1306 
1307 static int call_class_initializer_counter = 0;   // for debugging
1308 
1309 Method* InstanceKlass::class_initializer() const {
1310   Method* clinit = find_method(
1311       vmSymbols::class_initializer_name(), vmSymbols::void_method_signature());
1312   if (clinit != NULL && clinit->has_valid_initializer_flags()) {
1313     return clinit;
1314   }
1315   return NULL;
1316 }
1317 
1318 void InstanceKlass::call_class_initializer(TRAPS) {
1319   if (ReplayCompiles &&
1320       (ReplaySuppressInitializers == 1 ||
1321        (ReplaySuppressInitializers >= 2 && class_loader() != NULL))) {
1322     // Hide the existence of the initializer for the purpose of replaying the compile
1323     return;
1324   }
1325 
1326   methodHandle h_method(THREAD, class_initializer());
1327   assert(!is_initialized(), "we cannot initialize twice");
1328   LogTarget(Info, class, init) lt;
1329   if (lt.is_enabled()) {
1330     ResourceMark rm;
1331     LogStream ls(lt);
1332     ls.print("%d Initializing ", call_class_initializer_counter++);
1333     name()->print_value_on(&ls);
1334     ls.print_cr("%s (" INTPTR_FORMAT ")", h_method() == NULL ? "(no method)" : "", p2i(this));
1335   }
1336   if (h_method() != NULL) {
1337     JavaCallArguments args; // No arguments
1338     JavaValue result(T_VOID);
1339     JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args)
1340   }
1341 }
1342 
1343 
1344 void InstanceKlass::mask_for(const methodHandle& method, int bci,
1345   InterpreterOopMap* entry_for) {
1346   // Lazily create the _oop_map_cache at first request
1347   // Lock-free access requires load_acquire.
1348   OopMapCache* oop_map_cache = OrderAccess::load_acquire(&_oop_map_cache);
1349   if (oop_map_cache == NULL) {
1350     MutexLocker x(OopMapCacheAlloc_lock);
1351     // Check if _oop_map_cache was allocated while we were waiting for this lock
1352     if ((oop_map_cache = _oop_map_cache) == NULL) {
1353       oop_map_cache = new OopMapCache();
1354       // Ensure _oop_map_cache is stable, since it is examined without a lock
1355       OrderAccess::release_store(&_oop_map_cache, oop_map_cache);
1356     }
1357   }
1358   // _oop_map_cache is constant after init; lookup below does its own locking.
1359   oop_map_cache->lookup(method, bci, entry_for);
1360 }
1361 
1362 
1363 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1364   for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1365     Symbol* f_name = fs.name();
1366     Symbol* f_sig  = fs.signature();
1367     if (f_name == name && f_sig == sig) {
1368       fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1369       return true;
1370     }
1371   }
1372   return false;
1373 }
1374 
1375 
1376 Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1377   const int n = local_interfaces()->length();
1378   for (int i = 0; i < n; i++) {
1379     Klass* intf1 = local_interfaces()->at(i);
1380     assert(intf1->is_interface(), "just checking type");
1381     // search for field in current interface
1382     if (InstanceKlass::cast(intf1)->find_local_field(name, sig, fd)) {
1383       assert(fd->is_static(), "interface field must be static");
1384       return intf1;
1385     }
1386     // search for field in direct superinterfaces
1387     Klass* intf2 = InstanceKlass::cast(intf1)->find_interface_field(name, sig, fd);
1388     if (intf2 != NULL) return intf2;
1389   }
1390   // otherwise field lookup fails
1391   return NULL;
1392 }
1393 
1394 
1395 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1396   // search order according to newest JVM spec (5.4.3.2, p.167).
1397   // 1) search for field in current klass
1398   if (find_local_field(name, sig, fd)) {
1399     return const_cast<InstanceKlass*>(this);
1400   }
1401   // 2) search for field recursively in direct superinterfaces
1402   { Klass* intf = find_interface_field(name, sig, fd);
1403     if (intf != NULL) return intf;
1404   }
1405   // 3) apply field lookup recursively if superclass exists
1406   { Klass* supr = super();
1407     if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, fd);
1408   }
1409   // 4) otherwise field lookup fails
1410   return NULL;
1411 }
1412 
1413 
1414 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const {
1415   // search order according to newest JVM spec (5.4.3.2, p.167).
1416   // 1) search for field in current klass
1417   if (find_local_field(name, sig, fd)) {
1418     if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this);
1419   }
1420   // 2) search for field recursively in direct superinterfaces
1421   if (is_static) {
1422     Klass* intf = find_interface_field(name, sig, fd);
1423     if (intf != NULL) return intf;
1424   }
1425   // 3) apply field lookup recursively if superclass exists
1426   { Klass* supr = super();
1427     if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, is_static, fd);
1428   }
1429   // 4) otherwise field lookup fails
1430   return NULL;
1431 }
1432 
1433 
1434 bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1435   for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1436     if (fs.offset() == offset) {
1437       fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1438       if (fd->is_static() == is_static) return true;
1439     }
1440   }
1441   return false;
1442 }
1443 
1444 
1445 bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1446   Klass* klass = const_cast<InstanceKlass*>(this);
1447   while (klass != NULL) {
1448     if (InstanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) {
1449       return true;
1450     }
1451     klass = klass->super();
1452   }
1453   return false;
1454 }
1455 
1456 
1457 void InstanceKlass::methods_do(void f(Method* method)) {
1458   // Methods aren't stable until they are loaded.  This can be read outside
1459   // a lock through the ClassLoaderData for profiling
1460   if (!is_loaded()) {
1461     return;
1462   }
1463 
1464   int len = methods()->length();
1465   for (int index = 0; index < len; index++) {
1466     Method* m = methods()->at(index);
1467     assert(m->is_method(), "must be method");
1468     f(m);
1469   }
1470 }
1471 
1472 
1473 void InstanceKlass::do_local_static_fields(FieldClosure* cl) {
1474   for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1475     if (fs.access_flags().is_static()) {
1476       fieldDescriptor& fd = fs.field_descriptor();
1477       cl->do_field(&fd);
1478     }
1479   }
1480 }
1481 
1482 
1483 void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle mirror, TRAPS) {
1484   for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1485     if (fs.access_flags().is_static()) {
1486       fieldDescriptor& fd = fs.field_descriptor();
1487       f(&fd, mirror, CHECK);
1488     }
1489   }
1490 }
1491 
1492 
1493 static int compare_fields_by_offset(int* a, int* b) {
1494   return a[0] - b[0];
1495 }
1496 
1497 void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) {
1498   InstanceKlass* super = superklass();
1499   if (super != NULL) {
1500     super->do_nonstatic_fields(cl);
1501   }
1502   fieldDescriptor fd;
1503   int length = java_fields_count();
1504   // In DebugInfo nonstatic fields are sorted by offset.
1505   int* fields_sorted = NEW_C_HEAP_ARRAY(int, 2*(length+1), mtClass);
1506   int j = 0;
1507   for (int i = 0; i < length; i += 1) {
1508     fd.reinitialize(this, i);
1509     if (!fd.is_static()) {
1510       fields_sorted[j + 0] = fd.offset();
1511       fields_sorted[j + 1] = i;
1512       j += 2;
1513     }
1514   }
1515   if (j > 0) {
1516     length = j;
1517     // _sort_Fn is defined in growableArray.hpp.
1518     qsort(fields_sorted, length/2, 2*sizeof(int), (_sort_Fn)compare_fields_by_offset);
1519     for (int i = 0; i < length; i += 2) {
1520       fd.reinitialize(this, fields_sorted[i + 1]);
1521       assert(!fd.is_static() && fd.offset() == fields_sorted[i], "only nonstatic fields");
1522       cl->do_field(&fd);
1523     }
1524   }
1525   FREE_C_HEAP_ARRAY(int, fields_sorted);
1526 }
1527 
1528 
1529 void InstanceKlass::array_klasses_do(void f(Klass* k, TRAPS), TRAPS) {
1530   if (array_klasses() != NULL)
1531     ArrayKlass::cast(array_klasses())->array_klasses_do(f, THREAD);
1532 }
1533 
1534 void InstanceKlass::array_klasses_do(void f(Klass* k)) {
1535   if (array_klasses() != NULL)
1536     ArrayKlass::cast(array_klasses())->array_klasses_do(f);
1537 }
1538 
1539 #ifdef ASSERT
1540 static int linear_search(const Array<Method*>* methods,
1541                          const Symbol* name,
1542                          const Symbol* signature) {
1543   const int len = methods->length();
1544   for (int index = 0; index < len; index++) {
1545     const Method* const m = methods->at(index);
1546     assert(m->is_method(), "must be method");
1547     if (m->signature() == signature && m->name() == name) {
1548        return index;
1549     }
1550   }
1551   return -1;
1552 }
1553 #endif
1554 
1555 static int binary_search(const Array<Method*>* methods, const Symbol* name) {
1556   int len = methods->length();
1557   // methods are sorted, so do binary search
1558   int l = 0;
1559   int h = len - 1;
1560   while (l <= h) {
1561     int mid = (l + h) >> 1;
1562     Method* m = methods->at(mid);
1563     assert(m->is_method(), "must be method");
1564     int res = m->name()->fast_compare(name);
1565     if (res == 0) {
1566       return mid;
1567     } else if (res < 0) {
1568       l = mid + 1;
1569     } else {
1570       h = mid - 1;
1571     }
1572   }
1573   return -1;
1574 }
1575 
1576 // find_method looks up the name/signature in the local methods array
1577 Method* InstanceKlass::find_method(const Symbol* name,
1578                                    const Symbol* signature) const {
1579   return find_method_impl(name, signature, find_overpass, find_static, find_private);
1580 }
1581 
1582 Method* InstanceKlass::find_method_impl(const Symbol* name,
1583                                         const Symbol* signature,
1584                                         OverpassLookupMode overpass_mode,
1585                                         StaticLookupMode static_mode,
1586                                         PrivateLookupMode private_mode) const {
1587   return InstanceKlass::find_method_impl(methods(),
1588                                          name,
1589                                          signature,
1590                                          overpass_mode,
1591                                          static_mode,
1592                                          private_mode);
1593 }
1594 
1595 // find_instance_method looks up the name/signature in the local methods array
1596 // and skips over static methods
1597 Method* InstanceKlass::find_instance_method(const Array<Method*>* methods,
1598                                             const Symbol* name,
1599                                             const Symbol* signature,
1600                                             PrivateLookupMode private_mode) {
1601   Method* const meth = InstanceKlass::find_method_impl(methods,
1602                                                  name,
1603                                                  signature,
1604                                                  find_overpass,
1605                                                  skip_static,
1606                                                  private_mode);
1607   assert(((meth == NULL) || !meth->is_static()),
1608     "find_instance_method should have skipped statics");
1609   return meth;
1610 }
1611 
1612 // find_instance_method looks up the name/signature in the local methods array
1613 // and skips over static methods
1614 Method* InstanceKlass::find_instance_method(const Symbol* name,
1615                                             const Symbol* signature,
1616                                             PrivateLookupMode private_mode) const {
1617   return InstanceKlass::find_instance_method(methods(), name, signature, private_mode);
1618 }
1619 
1620 // Find looks up the name/signature in the local methods array
1621 // and filters on the overpass, static and private flags
1622 // This returns the first one found
1623 // note that the local methods array can have up to one overpass, one static
1624 // and one instance (private or not) with the same name/signature
1625 Method* InstanceKlass::find_local_method(const Symbol* name,
1626                                          const Symbol* signature,
1627                                          OverpassLookupMode overpass_mode,
1628                                          StaticLookupMode static_mode,
1629                                          PrivateLookupMode private_mode) const {
1630   return InstanceKlass::find_method_impl(methods(),
1631                                          name,
1632                                          signature,
1633                                          overpass_mode,
1634                                          static_mode,
1635                                          private_mode);
1636 }
1637 
1638 // Find looks up the name/signature in the local methods array
1639 // and filters on the overpass, static and private flags
1640 // This returns the first one found
1641 // note that the local methods array can have up to one overpass, one static
1642 // and one instance (private or not) with the same name/signature
1643 Method* InstanceKlass::find_local_method(const Array<Method*>* methods,
1644                                          const Symbol* name,
1645                                          const Symbol* signature,
1646                                          OverpassLookupMode overpass_mode,
1647                                          StaticLookupMode static_mode,
1648                                          PrivateLookupMode private_mode) {
1649   return InstanceKlass::find_method_impl(methods,
1650                                          name,
1651                                          signature,
1652                                          overpass_mode,
1653                                          static_mode,
1654                                          private_mode);
1655 }
1656 
1657 Method* InstanceKlass::find_method(const Array<Method*>* methods,
1658                                    const Symbol* name,
1659                                    const Symbol* signature) {
1660   return InstanceKlass::find_method_impl(methods,
1661                                          name,
1662                                          signature,
1663                                          find_overpass,
1664                                          find_static,
1665                                          find_private);
1666 }
1667 
1668 Method* InstanceKlass::find_method_impl(const Array<Method*>* methods,
1669                                         const Symbol* name,
1670                                         const Symbol* signature,
1671                                         OverpassLookupMode overpass_mode,
1672                                         StaticLookupMode static_mode,
1673                                         PrivateLookupMode private_mode) {
1674   int hit = find_method_index(methods, name, signature, overpass_mode, static_mode, private_mode);
1675   return hit >= 0 ? methods->at(hit): NULL;
1676 }
1677 
1678 // true if method matches signature and conforms to skipping_X conditions.
1679 static bool method_matches(const Method* m,
1680                            const Symbol* signature,
1681                            bool skipping_overpass,
1682                            bool skipping_static,
1683                            bool skipping_private) {
1684   return ((m->signature() == signature) &&
1685     (!skipping_overpass || !m->is_overpass()) &&
1686     (!skipping_static || !m->is_static()) &&
1687     (!skipping_private || !m->is_private()));
1688 }
1689 
1690 // Used directly for default_methods to find the index into the
1691 // default_vtable_indices, and indirectly by find_method
1692 // find_method_index looks in the local methods array to return the index
1693 // of the matching name/signature. If, overpass methods are being ignored,
1694 // the search continues to find a potential non-overpass match.  This capability
1695 // is important during method resolution to prefer a static method, for example,
1696 // over an overpass method.
1697 // There is the possibility in any _method's array to have the same name/signature
1698 // for a static method, an overpass method and a local instance method
1699 // To correctly catch a given method, the search criteria may need
1700 // to explicitly skip the other two. For local instance methods, it
1701 // is often necessary to skip private methods
1702 int InstanceKlass::find_method_index(const Array<Method*>* methods,
1703                                      const Symbol* name,
1704                                      const Symbol* signature,
1705                                      OverpassLookupMode overpass_mode,
1706                                      StaticLookupMode static_mode,
1707                                      PrivateLookupMode private_mode) {
1708   const bool skipping_overpass = (overpass_mode == skip_overpass);
1709   const bool skipping_static = (static_mode == skip_static);
1710   const bool skipping_private = (private_mode == skip_private);
1711   const int hit = binary_search(methods, name);
1712   if (hit != -1) {
1713     const Method* const m = methods->at(hit);
1714 
1715     // Do linear search to find matching signature.  First, quick check
1716     // for common case, ignoring overpasses if requested.
1717     if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1718       return hit;
1719     }
1720 
1721     // search downwards through overloaded methods
1722     int i;
1723     for (i = hit - 1; i >= 0; --i) {
1724         const Method* const m = methods->at(i);
1725         assert(m->is_method(), "must be method");
1726         if (m->name() != name) {
1727           break;
1728         }
1729         if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1730           return i;
1731         }
1732     }
1733     // search upwards
1734     for (i = hit + 1; i < methods->length(); ++i) {
1735         const Method* const m = methods->at(i);
1736         assert(m->is_method(), "must be method");
1737         if (m->name() != name) {
1738           break;
1739         }
1740         if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1741           return i;
1742         }
1743     }
1744     // not found
1745 #ifdef ASSERT
1746     const int index = (skipping_overpass || skipping_static || skipping_private) ? -1 :
1747       linear_search(methods, name, signature);
1748     assert(-1 == index, "binary search should have found entry %d", index);
1749 #endif
1750   }
1751   return -1;
1752 }
1753 
1754 int InstanceKlass::find_method_by_name(const Symbol* name, int* end) const {
1755   return find_method_by_name(methods(), name, end);
1756 }
1757 
1758 int InstanceKlass::find_method_by_name(const Array<Method*>* methods,
1759                                        const Symbol* name,
1760                                        int* end_ptr) {
1761   assert(end_ptr != NULL, "just checking");
1762   int start = binary_search(methods, name);
1763   int end = start + 1;
1764   if (start != -1) {
1765     while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start;
1766     while (end < methods->length() && (methods->at(end))->name() == name) ++end;
1767     *end_ptr = end;
1768     return start;
1769   }
1770   return -1;
1771 }
1772 
1773 // uncached_lookup_method searches both the local class methods array and all
1774 // superclasses methods arrays, skipping any overpass methods in superclasses,
1775 // and possibly skipping private methods.
1776 Method* InstanceKlass::uncached_lookup_method(const Symbol* name,
1777                                               const Symbol* signature,
1778                                               OverpassLookupMode overpass_mode,
1779                                               PrivateLookupMode private_mode) const {
1780   OverpassLookupMode overpass_local_mode = overpass_mode;
1781   const Klass* klass = this;
1782   while (klass != NULL) {
1783     Method* const method = InstanceKlass::cast(klass)->find_method_impl(name,
1784                                                                         signature,
1785                                                                         overpass_local_mode,
1786                                                                         find_static,
1787                                                                         private_mode);
1788     if (method != NULL) {
1789       return method;
1790     }
1791     klass = klass->super();
1792     overpass_local_mode = skip_overpass;   // Always ignore overpass methods in superclasses
1793   }
1794   return NULL;
1795 }
1796 
1797 #ifdef ASSERT
1798 // search through class hierarchy and return true if this class or
1799 // one of the superclasses was redefined
1800 bool InstanceKlass::has_redefined_this_or_super() const {
1801   const Klass* klass = this;
1802   while (klass != NULL) {
1803     if (InstanceKlass::cast(klass)->has_been_redefined()) {
1804       return true;
1805     }
1806     klass = klass->super();
1807   }
1808   return false;
1809 }
1810 #endif
1811 
1812 // lookup a method in the default methods list then in all transitive interfaces
1813 // Do NOT return private or static methods
1814 Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name,
1815                                                          Symbol* signature) const {
1816   Method* m = NULL;
1817   if (default_methods() != NULL) {
1818     m = find_method(default_methods(), name, signature);
1819   }
1820   // Look up interfaces
1821   if (m == NULL) {
1822     m = lookup_method_in_all_interfaces(name, signature, find_defaults);
1823   }
1824   return m;
1825 }
1826 
1827 // lookup a method in all the interfaces that this class implements
1828 // Do NOT return private or static methods, new in JDK8 which are not externally visible
1829 // They should only be found in the initial InterfaceMethodRef
1830 Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name,
1831                                                        Symbol* signature,
1832                                                        DefaultsLookupMode defaults_mode) const {
1833   Array<InstanceKlass*>* all_ifs = transitive_interfaces();
1834   int num_ifs = all_ifs->length();
1835   InstanceKlass *ik = NULL;
1836   for (int i = 0; i < num_ifs; i++) {
1837     ik = all_ifs->at(i);
1838     Method* m = ik->lookup_method(name, signature);
1839     if (m != NULL && m->is_public() && !m->is_static() &&
1840         ((defaults_mode != skip_defaults) || !m->is_default_method())) {
1841       return m;
1842     }
1843   }
1844   return NULL;
1845 }
1846 
1847 /* jni_id_for_impl for jfieldIds only */
1848 JNIid* InstanceKlass::jni_id_for_impl(int offset) {
1849   MutexLocker ml(JfieldIdCreation_lock);
1850   // Retry lookup after we got the lock
1851   JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset);
1852   if (probe == NULL) {
1853     // Slow case, allocate new static field identifier
1854     probe = new JNIid(this, offset, jni_ids());
1855     set_jni_ids(probe);
1856   }
1857   return probe;
1858 }
1859 
1860 
1861 /* jni_id_for for jfieldIds only */
1862 JNIid* InstanceKlass::jni_id_for(int offset) {
1863   JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset);
1864   if (probe == NULL) {
1865     probe = jni_id_for_impl(offset);
1866   }
1867   return probe;
1868 }
1869 
1870 u2 InstanceKlass::enclosing_method_data(int offset) const {
1871   const Array<jushort>* const inner_class_list = inner_classes();
1872   if (inner_class_list == NULL) {
1873     return 0;
1874   }
1875   const int length = inner_class_list->length();
1876   if (length % inner_class_next_offset == 0) {
1877     return 0;
1878   }
1879   const int index = length - enclosing_method_attribute_size;
1880   assert(offset < enclosing_method_attribute_size, "invalid offset");
1881   return inner_class_list->at(index + offset);
1882 }
1883 
1884 void InstanceKlass::set_enclosing_method_indices(u2 class_index,
1885                                                  u2 method_index) {
1886   Array<jushort>* inner_class_list = inner_classes();
1887   assert (inner_class_list != NULL, "_inner_classes list is not set up");
1888   int length = inner_class_list->length();
1889   if (length % inner_class_next_offset == enclosing_method_attribute_size) {
1890     int index = length - enclosing_method_attribute_size;
1891     inner_class_list->at_put(
1892       index + enclosing_method_class_index_offset, class_index);
1893     inner_class_list->at_put(
1894       index + enclosing_method_method_index_offset, method_index);
1895   }
1896 }
1897 
1898 // Lookup or create a jmethodID.
1899 // This code is called by the VMThread and JavaThreads so the
1900 // locking has to be done very carefully to avoid deadlocks
1901 // and/or other cache consistency problems.
1902 //
1903 jmethodID InstanceKlass::get_jmethod_id(const methodHandle& method_h) {
1904   size_t idnum = (size_t)method_h->method_idnum();
1905   jmethodID* jmeths = methods_jmethod_ids_acquire();
1906   size_t length = 0;
1907   jmethodID id = NULL;
1908 
1909   // We use a double-check locking idiom here because this cache is
1910   // performance sensitive. In the normal system, this cache only
1911   // transitions from NULL to non-NULL which is safe because we use
1912   // release_set_methods_jmethod_ids() to advertise the new cache.
1913   // A partially constructed cache should never be seen by a racing
1914   // thread. We also use release_store() to save a new jmethodID
1915   // in the cache so a partially constructed jmethodID should never be
1916   // seen either. Cache reads of existing jmethodIDs proceed without a
1917   // lock, but cache writes of a new jmethodID requires uniqueness and
1918   // creation of the cache itself requires no leaks so a lock is
1919   // generally acquired in those two cases.
1920   //
1921   // If the RedefineClasses() API has been used, then this cache can
1922   // grow and we'll have transitions from non-NULL to bigger non-NULL.
1923   // Cache creation requires no leaks and we require safety between all
1924   // cache accesses and freeing of the old cache so a lock is generally
1925   // acquired when the RedefineClasses() API has been used.
1926 
1927   if (jmeths != NULL) {
1928     // the cache already exists
1929     if (!idnum_can_increment()) {
1930       // the cache can't grow so we can just get the current values
1931       get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1932     } else {
1933       // cache can grow so we have to be more careful
1934       if (Threads::number_of_threads() == 0 ||
1935           SafepointSynchronize::is_at_safepoint()) {
1936         // we're single threaded or at a safepoint - no locking needed
1937         get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1938       } else {
1939         MutexLocker ml(JmethodIdCreation_lock);
1940         get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1941       }
1942     }
1943   }
1944   // implied else:
1945   // we need to allocate a cache so default length and id values are good
1946 
1947   if (jmeths == NULL ||   // no cache yet
1948       length <= idnum ||  // cache is too short
1949       id == NULL) {       // cache doesn't contain entry
1950 
1951     // This function can be called by the VMThread so we have to do all
1952     // things that might block on a safepoint before grabbing the lock.
1953     // Otherwise, we can deadlock with the VMThread or have a cache
1954     // consistency issue. These vars keep track of what we might have
1955     // to free after the lock is dropped.
1956     jmethodID  to_dealloc_id     = NULL;
1957     jmethodID* to_dealloc_jmeths = NULL;
1958 
1959     // may not allocate new_jmeths or use it if we allocate it
1960     jmethodID* new_jmeths = NULL;
1961     if (length <= idnum) {
1962       // allocate a new cache that might be used
1963       size_t size = MAX2(idnum+1, (size_t)idnum_allocated_count());
1964       new_jmeths = NEW_C_HEAP_ARRAY(jmethodID, size+1, mtClass);
1965       memset(new_jmeths, 0, (size+1)*sizeof(jmethodID));
1966       // cache size is stored in element[0], other elements offset by one
1967       new_jmeths[0] = (jmethodID)size;
1968     }
1969 
1970     // allocate a new jmethodID that might be used
1971     jmethodID new_id = NULL;
1972     if (method_h->is_old() && !method_h->is_obsolete()) {
1973       // The method passed in is old (but not obsolete), we need to use the current version
1974       Method* current_method = method_with_idnum((int)idnum);
1975       assert(current_method != NULL, "old and but not obsolete, so should exist");
1976       new_id = Method::make_jmethod_id(class_loader_data(), current_method);
1977     } else {
1978       // It is the current version of the method or an obsolete method,
1979       // use the version passed in
1980       new_id = Method::make_jmethod_id(class_loader_data(), method_h());
1981     }
1982 
1983     if (Threads::number_of_threads() == 0 ||
1984         SafepointSynchronize::is_at_safepoint()) {
1985       // we're single threaded or at a safepoint - no locking needed
1986       id = get_jmethod_id_fetch_or_update(idnum, new_id, new_jmeths,
1987                                           &to_dealloc_id, &to_dealloc_jmeths);
1988     } else {
1989       MutexLocker ml(JmethodIdCreation_lock);
1990       id = get_jmethod_id_fetch_or_update(idnum, new_id, new_jmeths,
1991                                           &to_dealloc_id, &to_dealloc_jmeths);
1992     }
1993 
1994     // The lock has been dropped so we can free resources.
1995     // Free up either the old cache or the new cache if we allocated one.
1996     if (to_dealloc_jmeths != NULL) {
1997       FreeHeap(to_dealloc_jmeths);
1998     }
1999     // free up the new ID since it wasn't needed
2000     if (to_dealloc_id != NULL) {
2001       Method::destroy_jmethod_id(class_loader_data(), to_dealloc_id);
2002     }
2003   }
2004   return id;
2005 }
2006 
2007 // Figure out how many jmethodIDs haven't been allocated, and make
2008 // sure space for them is pre-allocated.  This makes getting all
2009 // method ids much, much faster with classes with more than 8
2010 // methods, and has a *substantial* effect on performance with jvmti
2011 // code that loads all jmethodIDs for all classes.
2012 void InstanceKlass::ensure_space_for_methodids(int start_offset) {
2013   int new_jmeths = 0;
2014   int length = methods()->length();
2015   for (int index = start_offset; index < length; index++) {
2016     Method* m = methods()->at(index);
2017     jmethodID id = m->find_jmethod_id_or_null();
2018     if (id == NULL) {
2019       new_jmeths++;
2020     }
2021   }
2022   if (new_jmeths != 0) {
2023     Method::ensure_jmethod_ids(class_loader_data(), new_jmeths);
2024   }
2025 }
2026 
2027 // Common code to fetch the jmethodID from the cache or update the
2028 // cache with the new jmethodID. This function should never do anything
2029 // that causes the caller to go to a safepoint or we can deadlock with
2030 // the VMThread or have cache consistency issues.
2031 //
2032 jmethodID InstanceKlass::get_jmethod_id_fetch_or_update(
2033             size_t idnum, jmethodID new_id,
2034             jmethodID* new_jmeths, jmethodID* to_dealloc_id_p,
2035             jmethodID** to_dealloc_jmeths_p) {
2036   assert(new_id != NULL, "sanity check");
2037   assert(to_dealloc_id_p != NULL, "sanity check");
2038   assert(to_dealloc_jmeths_p != NULL, "sanity check");
2039   assert(Threads::number_of_threads() == 0 ||
2040          SafepointSynchronize::is_at_safepoint() ||
2041          JmethodIdCreation_lock->owned_by_self(), "sanity check");
2042 
2043   // reacquire the cache - we are locked, single threaded or at a safepoint
2044   jmethodID* jmeths = methods_jmethod_ids_acquire();
2045   jmethodID  id     = NULL;
2046   size_t     length = 0;
2047 
2048   if (jmeths == NULL ||                         // no cache yet
2049       (length = (size_t)jmeths[0]) <= idnum) {  // cache is too short
2050     if (jmeths != NULL) {
2051       // copy any existing entries from the old cache
2052       for (size_t index = 0; index < length; index++) {
2053         new_jmeths[index+1] = jmeths[index+1];
2054       }
2055       *to_dealloc_jmeths_p = jmeths;  // save old cache for later delete
2056     }
2057     release_set_methods_jmethod_ids(jmeths = new_jmeths);
2058   } else {
2059     // fetch jmethodID (if any) from the existing cache
2060     id = jmeths[idnum+1];
2061     *to_dealloc_jmeths_p = new_jmeths;  // save new cache for later delete
2062   }
2063   if (id == NULL) {
2064     // No matching jmethodID in the existing cache or we have a new
2065     // cache or we just grew the cache. This cache write is done here
2066     // by the first thread to win the foot race because a jmethodID
2067     // needs to be unique once it is generally available.
2068     id = new_id;
2069 
2070     // The jmethodID cache can be read while unlocked so we have to
2071     // make sure the new jmethodID is complete before installing it
2072     // in the cache.
2073     OrderAccess::release_store(&jmeths[idnum+1], id);
2074   } else {
2075     *to_dealloc_id_p = new_id; // save new id for later delete
2076   }
2077   return id;
2078 }
2079 
2080 
2081 // Common code to get the jmethodID cache length and the jmethodID
2082 // value at index idnum if there is one.
2083 //
2084 void InstanceKlass::get_jmethod_id_length_value(jmethodID* cache,
2085        size_t idnum, size_t *length_p, jmethodID* id_p) {
2086   assert(cache != NULL, "sanity check");
2087   assert(length_p != NULL, "sanity check");
2088   assert(id_p != NULL, "sanity check");
2089 
2090   // cache size is stored in element[0], other elements offset by one
2091   *length_p = (size_t)cache[0];
2092   if (*length_p <= idnum) {  // cache is too short
2093     *id_p = NULL;
2094   } else {
2095     *id_p = cache[idnum+1];  // fetch jmethodID (if any)
2096   }
2097 }
2098 
2099 
2100 // Lookup a jmethodID, NULL if not found.  Do no blocking, no allocations, no handles
2101 jmethodID InstanceKlass::jmethod_id_or_null(Method* method) {
2102   size_t idnum = (size_t)method->method_idnum();
2103   jmethodID* jmeths = methods_jmethod_ids_acquire();
2104   size_t length;                                // length assigned as debugging crumb
2105   jmethodID id = NULL;
2106   if (jmeths != NULL &&                         // If there is a cache
2107       (length = (size_t)jmeths[0]) > idnum) {   // and if it is long enough,
2108     id = jmeths[idnum+1];                       // Look up the id (may be NULL)
2109   }
2110   return id;
2111 }
2112 
2113 inline DependencyContext InstanceKlass::dependencies() {
2114   DependencyContext dep_context(&_dep_context, &_dep_context_last_cleaned);
2115   return dep_context;
2116 }
2117 
2118 int InstanceKlass::mark_dependent_nmethods(KlassDepChange& changes) {
2119   return dependencies().mark_dependent_nmethods(changes);
2120 }
2121 
2122 void InstanceKlass::add_dependent_nmethod(nmethod* nm) {
2123   dependencies().add_dependent_nmethod(nm);
2124 }
2125 
2126 void InstanceKlass::remove_dependent_nmethod(nmethod* nm) {
2127   dependencies().remove_dependent_nmethod(nm);
2128 }
2129 
2130 void InstanceKlass::clean_dependency_context() {
2131   dependencies().clean_unloading_dependents();
2132 }
2133 
2134 #ifndef PRODUCT
2135 void InstanceKlass::print_dependent_nmethods(bool verbose) {
2136   dependencies().print_dependent_nmethods(verbose);
2137 }
2138 
2139 bool InstanceKlass::is_dependent_nmethod(nmethod* nm) {
2140   return dependencies().is_dependent_nmethod(nm);
2141 }
2142 #endif //PRODUCT
2143 
2144 void InstanceKlass::clean_weak_instanceklass_links() {
2145   clean_implementors_list();
2146   clean_method_data();
2147 }
2148 
2149 void InstanceKlass::clean_implementors_list() {
2150   assert(is_loader_alive(), "this klass should be live");
2151   if (is_interface()) {
2152     if (ClassUnloading) {
2153       Klass* impl = implementor();
2154       if (impl != NULL) {
2155         if (!impl->is_loader_alive()) {
2156           // remove this guy
2157           Klass** klass = adr_implementor();
2158           assert(klass != NULL, "null klass");
2159           if (klass != NULL) {
2160             *klass = NULL;
2161           }
2162         }
2163       }
2164     }
2165   }
2166 }
2167 
2168 void InstanceKlass::clean_method_data() {
2169   for (int m = 0; m < methods()->length(); m++) {
2170     MethodData* mdo = methods()->at(m)->method_data();
2171     if (mdo != NULL) {
2172       mdo->clean_method_data(/*always_clean*/false);
2173     }
2174   }
2175 }
2176 
2177 bool InstanceKlass::supers_have_passed_fingerprint_checks() {
2178   if (java_super() != NULL && !java_super()->has_passed_fingerprint_check()) {
2179     ResourceMark rm;
2180     log_trace(class, fingerprint)("%s : super %s not fingerprinted", external_name(), java_super()->external_name());
2181     return false;
2182   }
2183 
2184   Array<InstanceKlass*>* local_interfaces = this->local_interfaces();
2185   if (local_interfaces != NULL) {
2186     int length = local_interfaces->length();
2187     for (int i = 0; i < length; i++) {
2188       InstanceKlass* intf = local_interfaces->at(i);
2189       if (!intf->has_passed_fingerprint_check()) {
2190         ResourceMark rm;
2191         log_trace(class, fingerprint)("%s : interface %s not fingerprinted", external_name(), intf->external_name());
2192         return false;
2193       }
2194     }
2195   }
2196 
2197   return true;
2198 }
2199 
2200 bool InstanceKlass::should_store_fingerprint(bool is_unsafe_anonymous) {
2201 #if INCLUDE_AOT
2202   // We store the fingerprint into the InstanceKlass only in the following 2 cases:
2203   if (CalculateClassFingerprint) {
2204     // (1) We are running AOT to generate a shared library.
2205     return true;
2206   }
2207   if (DumpSharedSpaces) {
2208     // (2) We are running -Xshare:dump to create a shared archive
2209     return true;
2210   }
2211   if (UseAOT && is_unsafe_anonymous) {
2212     // (3) We are using AOT code from a shared library and see an unsafe anonymous class
2213     return true;
2214   }
2215 #endif
2216 
2217   // In all other cases we might set the _misc_has_passed_fingerprint_check bit,
2218   // but do not store the 64-bit fingerprint to save space.
2219   return false;
2220 }
2221 
2222 bool InstanceKlass::has_stored_fingerprint() const {
2223 #if INCLUDE_AOT
2224   return should_store_fingerprint() || is_shared();
2225 #else
2226   return false;
2227 #endif
2228 }
2229 
2230 uint64_t InstanceKlass::get_stored_fingerprint() const {
2231   address adr = adr_fingerprint();
2232   if (adr != NULL) {
2233     return (uint64_t)Bytes::get_native_u8(adr); // adr may not be 64-bit aligned
2234   }
2235   return 0;
2236 }
2237 
2238 void InstanceKlass::store_fingerprint(uint64_t fingerprint) {
2239   address adr = adr_fingerprint();
2240   if (adr != NULL) {
2241     Bytes::put_native_u8(adr, (u8)fingerprint); // adr may not be 64-bit aligned
2242 
2243     ResourceMark rm;
2244     log_trace(class, fingerprint)("stored as " PTR64_FORMAT " for class %s", fingerprint, external_name());
2245   }
2246 }
2247 
2248 void InstanceKlass::metaspace_pointers_do(MetaspaceClosure* it) {
2249   Klass::metaspace_pointers_do(it);
2250 
2251   if (log_is_enabled(Trace, cds)) {
2252     ResourceMark rm;
2253     log_trace(cds)("Iter(InstanceKlass): %p (%s)", this, external_name());
2254   }
2255 
2256   it->push(&_annotations);
2257   it->push((Klass**)&_array_klasses);
2258   it->push(&_constants);
2259   it->push(&_inner_classes);
2260   it->push(&_array_name);
2261 #if INCLUDE_JVMTI
2262   it->push(&_previous_versions);
2263 #endif
2264   it->push(&_methods);
2265   it->push(&_default_methods);
2266   it->push(&_local_interfaces);
2267   it->push(&_transitive_interfaces);
2268   it->push(&_method_ordering);
2269   it->push(&_default_vtable_indices);
2270   it->push(&_fields);
2271 
2272   if (itable_length() > 0) {
2273     itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2274     int method_table_offset_in_words = ioe->offset()/wordSize;
2275     int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words())
2276                          / itableOffsetEntry::size();
2277 
2278     for (int i = 0; i < nof_interfaces; i ++, ioe ++) {
2279       if (ioe->interface_klass() != NULL) {
2280         it->push(ioe->interface_klass_addr());
2281         itableMethodEntry* ime = ioe->first_method_entry(this);
2282         int n = klassItable::method_count_for_interface(ioe->interface_klass());
2283         for (int index = 0; index < n; index ++) {
2284           it->push(ime[index].method_addr());
2285         }
2286       }
2287     }
2288   }
2289 
2290   it->push(&_nest_members);
2291 }
2292 
2293 void InstanceKlass::remove_unshareable_info() {
2294   Klass::remove_unshareable_info();
2295 
2296   if (is_in_error_state()) {
2297     // Classes are attempted to link during dumping and may fail,
2298     // but these classes are still in the dictionary and class list in CLD.
2299     // Check in_error state first because in_error is > linked state, so
2300     // is_linked() is true.
2301     // If there's a linking error, there is nothing else to remove.
2302     return;
2303   }
2304 
2305   // Reset to the 'allocated' state to prevent any premature accessing to
2306   // a shared class at runtime while the class is still being loaded and
2307   // restored. A class' init_state is set to 'loaded' at runtime when it's
2308   // being added to class hierarchy (see SystemDictionary:::add_to_hierarchy()).
2309   _init_state = allocated;
2310 
2311   {
2312     MutexLocker ml(Compile_lock);
2313     init_implementor();
2314   }
2315 
2316   constants()->remove_unshareable_info();
2317 
2318   for (int i = 0; i < methods()->length(); i++) {
2319     Method* m = methods()->at(i);
2320     m->remove_unshareable_info();
2321   }
2322 
2323   // do array classes also.
2324   if (array_klasses() != NULL) {
2325     array_klasses()->remove_unshareable_info();
2326   }
2327 
2328   // These are not allocated from metaspace, but they should should all be empty
2329   // during dump time, so we don't need to worry about them in InstanceKlass::iterate().
2330   guarantee(_source_debug_extension == NULL, "must be");
2331   guarantee(_dep_context == NULL, "must be");
2332   guarantee(_osr_nmethods_head == NULL, "must be");
2333 
2334 #if INCLUDE_JVMTI
2335   guarantee(_breakpoints == NULL, "must be");
2336   guarantee(_previous_versions == NULL, "must be");
2337 #endif
2338 
2339   _init_thread = NULL;
2340   _methods_jmethod_ids = NULL;
2341   _jni_ids = NULL;
2342   _oop_map_cache = NULL;
2343   // clear _nest_host to ensure re-load at runtime
2344   _nest_host = NULL;
2345 }
2346 
2347 void InstanceKlass::remove_java_mirror() {
2348   Klass::remove_java_mirror();
2349 
2350   // do array classes also.
2351   if (array_klasses() != NULL) {
2352     array_klasses()->remove_java_mirror();
2353   }
2354 }
2355 
2356 void InstanceKlass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain, TRAPS) {
2357   // SystemDictionary::add_to_hierarchy() sets the init_state to loaded
2358   // before the InstanceKlass is added to the SystemDictionary. Make
2359   // sure the current state is <loaded.
2360   assert(!is_loaded(), "invalid init state");
2361   set_package(loader_data, CHECK);
2362   Klass::restore_unshareable_info(loader_data, protection_domain, CHECK);
2363 
2364   Array<Method*>* methods = this->methods();
2365   int num_methods = methods->length();
2366   for (int index2 = 0; index2 < num_methods; ++index2) {
2367     methodHandle m(THREAD, methods->at(index2));
2368     m->restore_unshareable_info(CHECK);
2369   }
2370   if (JvmtiExport::has_redefined_a_class()) {
2371     // Reinitialize vtable because RedefineClasses may have changed some
2372     // entries in this vtable for super classes so the CDS vtable might
2373     // point to old or obsolete entries.  RedefineClasses doesn't fix up
2374     // vtables in the shared system dictionary, only the main one.
2375     // It also redefines the itable too so fix that too.
2376     vtable().initialize_vtable(false, CHECK);
2377     itable().initialize_itable(false, CHECK);
2378   }
2379 
2380   // restore constant pool resolved references
2381   constants()->restore_unshareable_info(CHECK);
2382 
2383   if (array_klasses() != NULL) {
2384     // Array classes have null protection domain.
2385     // --> see ArrayKlass::complete_create_array_klass()
2386     array_klasses()->restore_unshareable_info(ClassLoaderData::the_null_class_loader_data(), Handle(), CHECK);
2387   }
2388 }
2389 
2390 // returns true IFF is_in_error_state() has been changed as a result of this call.
2391 bool InstanceKlass::check_sharing_error_state() {
2392   assert(DumpSharedSpaces, "should only be called during dumping");
2393   bool old_state = is_in_error_state();
2394 
2395   if (!is_in_error_state()) {
2396     bool bad = false;
2397     for (InstanceKlass* sup = java_super(); sup; sup = sup->java_super()) {
2398       if (sup->is_in_error_state()) {
2399         bad = true;
2400         break;
2401       }
2402     }
2403     if (!bad) {
2404       Array<InstanceKlass*>* interfaces = transitive_interfaces();
2405       for (int i = 0; i < interfaces->length(); i++) {
2406         InstanceKlass* iface = interfaces->at(i);
2407         if (iface->is_in_error_state()) {
2408           bad = true;
2409           break;
2410         }
2411       }
2412     }
2413 
2414     if (bad) {
2415       set_in_error_state();
2416     }
2417   }
2418 
2419   return (old_state != is_in_error_state());
2420 }
2421 
2422 #if INCLUDE_JVMTI
2423 static void clear_all_breakpoints(Method* m) {
2424   m->clear_all_breakpoints();
2425 }
2426 #endif
2427 
2428 void InstanceKlass::unload_class(InstanceKlass* ik) {
2429   // Release dependencies.
2430   ik->dependencies().remove_all_dependents();
2431 
2432   // notify the debugger
2433   if (JvmtiExport::should_post_class_unload()) {
2434     JvmtiExport::post_class_unload(ik);
2435   }
2436 
2437   // notify ClassLoadingService of class unload
2438   ClassLoadingService::notify_class_unloaded(ik);
2439 
2440 #if INCLUDE_JFR
2441   assert(ik != NULL, "invariant");
2442   EventClassUnload event;
2443   event.set_unloadedClass(ik);
2444   event.set_definingClassLoader(ik->class_loader_data());
2445   event.commit();
2446 #endif
2447 }
2448 
2449 void InstanceKlass::release_C_heap_structures(InstanceKlass* ik) {
2450   // Clean up C heap
2451   ik->release_C_heap_structures();
2452   ik->constants()->release_C_heap_structures();
2453 }
2454 
2455 void InstanceKlass::release_C_heap_structures() {
2456   // Can't release the constant pool here because the constant pool can be
2457   // deallocated separately from the InstanceKlass for default methods and
2458   // redefine classes.
2459 
2460   // Deallocate oop map cache
2461   if (_oop_map_cache != NULL) {
2462     delete _oop_map_cache;
2463     _oop_map_cache = NULL;
2464   }
2465 
2466   // Deallocate JNI identifiers for jfieldIDs
2467   JNIid::deallocate(jni_ids());
2468   set_jni_ids(NULL);
2469 
2470   jmethodID* jmeths = methods_jmethod_ids_acquire();
2471   if (jmeths != (jmethodID*)NULL) {
2472     release_set_methods_jmethod_ids(NULL);
2473     FreeHeap(jmeths);
2474   }
2475 
2476   assert(_dep_context == NULL,
2477          "dependencies should already be cleaned");
2478 
2479 #if INCLUDE_JVMTI
2480   // Deallocate breakpoint records
2481   if (breakpoints() != 0x0) {
2482     methods_do(clear_all_breakpoints);
2483     assert(breakpoints() == 0x0, "should have cleared breakpoints");
2484   }
2485 
2486   // deallocate the cached class file
2487   if (_cached_class_file != NULL && !MetaspaceShared::is_in_shared_metaspace(_cached_class_file)) {
2488     os::free(_cached_class_file);
2489     _cached_class_file = NULL;
2490   }
2491 #endif
2492 
2493   // Decrement symbol reference counts associated with the unloaded class.
2494   if (_name != NULL) _name->decrement_refcount();
2495   // unreference array name derived from this class name (arrays of an unloaded
2496   // class can't be referenced anymore).
2497   if (_array_name != NULL)  _array_name->decrement_refcount();
2498   if (_source_debug_extension != NULL) FREE_C_HEAP_ARRAY(char, _source_debug_extension);
2499 }
2500 
2501 void InstanceKlass::set_source_debug_extension(const char* array, int length) {
2502   if (array == NULL) {
2503     _source_debug_extension = NULL;
2504   } else {
2505     // Adding one to the attribute length in order to store a null terminator
2506     // character could cause an overflow because the attribute length is
2507     // already coded with an u4 in the classfile, but in practice, it's
2508     // unlikely to happen.
2509     assert((length+1) > length, "Overflow checking");
2510     char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass);
2511     for (int i = 0; i < length; i++) {
2512       sde[i] = array[i];
2513     }
2514     sde[length] = '\0';
2515     _source_debug_extension = sde;
2516   }
2517 }
2518 
2519 const char* InstanceKlass::signature_name() const {
2520   int hash_len = 0;
2521   char hash_buf[40];
2522 
2523   // If this is an unsafe anonymous class, append a hash to make the name unique
2524   if (is_unsafe_anonymous()) {
2525     intptr_t hash = (java_mirror() != NULL) ? java_mirror()->identity_hash() : 0;
2526     jio_snprintf(hash_buf, sizeof(hash_buf), "/" UINTX_FORMAT, (uintx)hash);
2527     hash_len = (int)strlen(hash_buf);
2528   }
2529 
2530   // Get the internal name as a c string
2531   const char* src = (const char*) (name()->as_C_string());
2532   const int src_length = (int)strlen(src);
2533 
2534   char* dest = NEW_RESOURCE_ARRAY(char, src_length + hash_len + 3);
2535 
2536   // Add L as type indicator
2537   int dest_index = 0;
2538   dest[dest_index++] = 'L';
2539 
2540   // Add the actual class name
2541   for (int src_index = 0; src_index < src_length; ) {
2542     dest[dest_index++] = src[src_index++];
2543   }
2544 
2545   // If we have a hash, append it
2546   for (int hash_index = 0; hash_index < hash_len; ) {
2547     dest[dest_index++] = hash_buf[hash_index++];
2548   }
2549 
2550   // Add the semicolon and the NULL
2551   dest[dest_index++] = ';';
2552   dest[dest_index] = '\0';
2553   return dest;
2554 }
2555 
2556 // Used to obtain the package name from a fully qualified class name.
2557 Symbol* InstanceKlass::package_from_name(const Symbol* name, TRAPS) {
2558   if (name == NULL) {
2559     return NULL;
2560   } else {
2561     if (name->utf8_length() <= 0) {
2562       return NULL;
2563     }
2564     ResourceMark rm;
2565     const char* package_name = ClassLoader::package_from_name((const char*) name->as_C_string());
2566     if (package_name == NULL) {
2567       return NULL;
2568     }
2569     Symbol* pkg_name = SymbolTable::new_symbol(package_name, THREAD);
2570     return pkg_name;
2571   }
2572 }
2573 
2574 ModuleEntry* InstanceKlass::module() const {
2575   // For an unsafe anonymous class return the host class' module
2576   if (is_unsafe_anonymous()) {
2577     assert(unsafe_anonymous_host() != NULL, "unsafe anonymous class must have a host class");
2578     return unsafe_anonymous_host()->module();
2579   }
2580 
2581   // Class is in a named package
2582   if (!in_unnamed_package()) {
2583     return _package_entry->module();
2584   }
2585 
2586   // Class is in an unnamed package, return its loader's unnamed module
2587   return class_loader_data()->unnamed_module();
2588 }
2589 
2590 void InstanceKlass::set_package(ClassLoaderData* loader_data, TRAPS) {
2591 
2592   // ensure java/ packages only loaded by boot or platform builtin loaders
2593   check_prohibited_package(name(), loader_data, CHECK);
2594 
2595   TempNewSymbol pkg_name = package_from_name(name(), CHECK);
2596 
2597   if (pkg_name != NULL && loader_data != NULL) {
2598 
2599     // Find in class loader's package entry table.
2600     _package_entry = loader_data->packages()->lookup_only(pkg_name);
2601 
2602     // If the package name is not found in the loader's package
2603     // entry table, it is an indication that the package has not
2604     // been defined. Consider it defined within the unnamed module.
2605     if (_package_entry == NULL) {
2606       ResourceMark rm;
2607 
2608       if (!ModuleEntryTable::javabase_defined()) {
2609         // Before java.base is defined during bootstrapping, define all packages in
2610         // the java.base module.  If a non-java.base package is erroneously placed
2611         // in the java.base module it will be caught later when java.base
2612         // is defined by ModuleEntryTable::verify_javabase_packages check.
2613         assert(ModuleEntryTable::javabase_moduleEntry() != NULL, JAVA_BASE_NAME " module is NULL");
2614         _package_entry = loader_data->packages()->lookup(pkg_name, ModuleEntryTable::javabase_moduleEntry());
2615       } else {
2616         assert(loader_data->unnamed_module() != NULL, "unnamed module is NULL");
2617         _package_entry = loader_data->packages()->lookup(pkg_name,
2618                                                          loader_data->unnamed_module());
2619       }
2620 
2621       // A package should have been successfully created
2622       assert(_package_entry != NULL, "Package entry for class %s not found, loader %s",
2623              name()->as_C_string(), loader_data->loader_name_and_id());
2624     }
2625 
2626     if (log_is_enabled(Debug, module)) {
2627       ResourceMark rm;
2628       ModuleEntry* m = _package_entry->module();
2629       log_trace(module)("Setting package: class: %s, package: %s, loader: %s, module: %s",
2630                         external_name(),
2631                         pkg_name->as_C_string(),
2632                         loader_data->loader_name_and_id(),
2633                         (m->is_named() ? m->name()->as_C_string() : UNNAMED_MODULE));
2634     }
2635   } else {
2636     ResourceMark rm;
2637     log_trace(module)("Setting package: class: %s, package: unnamed, loader: %s, module: %s",
2638                       external_name(),
2639                       (loader_data != NULL) ? loader_data->loader_name_and_id() : "NULL",
2640                       UNNAMED_MODULE);
2641   }
2642 }
2643 
2644 
2645 // different versions of is_same_class_package
2646 
2647 bool InstanceKlass::is_same_class_package(const Klass* class2) const {
2648   oop classloader1 = this->class_loader();
2649   PackageEntry* classpkg1 = this->package();
2650   if (class2->is_objArray_klass()) {
2651     class2 = ObjArrayKlass::cast(class2)->bottom_klass();
2652   }
2653 
2654   oop classloader2;
2655   PackageEntry* classpkg2;
2656   if (class2->is_instance_klass()) {
2657     classloader2 = class2->class_loader();
2658     classpkg2 = class2->package();
2659   } else {
2660     assert(class2->is_typeArray_klass(), "should be type array");
2661     classloader2 = NULL;
2662     classpkg2 = NULL;
2663   }
2664 
2665   // Same package is determined by comparing class loader
2666   // and package entries. Both must be the same. This rule
2667   // applies even to classes that are defined in the unnamed
2668   // package, they still must have the same class loader.
2669   if (oopDesc::equals(classloader1, classloader2) && (classpkg1 == classpkg2)) {
2670     return true;
2671   }
2672 
2673   return false;
2674 }
2675 
2676 // return true if this class and other_class are in the same package. Classloader
2677 // and classname information is enough to determine a class's package
2678 bool InstanceKlass::is_same_class_package(oop other_class_loader,
2679                                           const Symbol* other_class_name) const {
2680   if (!oopDesc::equals(class_loader(), other_class_loader)) {
2681     return false;
2682   }
2683   if (name()->fast_compare(other_class_name) == 0) {
2684      return true;
2685   }
2686 
2687   {
2688     ResourceMark rm;
2689 
2690     bool bad_class_name = false;
2691     const char* other_pkg =
2692       ClassLoader::package_from_name((const char*) other_class_name->as_C_string(), &bad_class_name);
2693     if (bad_class_name) {
2694       return false;
2695     }
2696     // Check that package_from_name() returns NULL, not "", if there is no package.
2697     assert(other_pkg == NULL || strlen(other_pkg) > 0, "package name is empty string");
2698 
2699     const Symbol* const this_package_name =
2700       this->package() != NULL ? this->package()->name() : NULL;
2701 
2702     if (this_package_name == NULL || other_pkg == NULL) {
2703       // One of the two doesn't have a package.  Only return true if the other
2704       // one also doesn't have a package.
2705       return (const char*)this_package_name == other_pkg;
2706     }
2707 
2708     // Check if package is identical
2709     return this_package_name->equals(other_pkg);
2710   }
2711 }
2712 
2713 // Returns true iff super_method can be overridden by a method in targetclassname
2714 // See JLS 3rd edition 8.4.6.1
2715 // Assumes name-signature match
2716 // "this" is InstanceKlass of super_method which must exist
2717 // note that the InstanceKlass of the method in the targetclassname has not always been created yet
2718 bool InstanceKlass::is_override(const methodHandle& super_method, Handle targetclassloader, Symbol* targetclassname, TRAPS) {
2719    // Private methods can not be overridden
2720    if (super_method->is_private()) {
2721      return false;
2722    }
2723    // If super method is accessible, then override
2724    if ((super_method->is_protected()) ||
2725        (super_method->is_public())) {
2726      return true;
2727    }
2728    // Package-private methods are not inherited outside of package
2729    assert(super_method->is_package_private(), "must be package private");
2730    return(is_same_class_package(targetclassloader(), targetclassname));
2731 }
2732 
2733 // Only boot and platform class loaders can define classes in "java/" packages.
2734 void InstanceKlass::check_prohibited_package(Symbol* class_name,
2735                                              ClassLoaderData* loader_data,
2736                                              TRAPS) {
2737   if (!loader_data->is_boot_class_loader_data() &&
2738       !loader_data->is_platform_class_loader_data() &&
2739       class_name != NULL) {
2740     ResourceMark rm(THREAD);
2741     char* name = class_name->as_C_string();
2742     if (strncmp(name, JAVAPKG, JAVAPKG_LEN) == 0 && name[JAVAPKG_LEN] == '/') {
2743       TempNewSymbol pkg_name = InstanceKlass::package_from_name(class_name, CHECK);
2744       assert(pkg_name != NULL, "Error in parsing package name starting with 'java/'");
2745       name = pkg_name->as_C_string();
2746       const char* class_loader_name = loader_data->loader_name_and_id();
2747       StringUtils::replace_no_expand(name, "/", ".");
2748       const char* msg_text1 = "Class loader (instance of): ";
2749       const char* msg_text2 = " tried to load prohibited package name: ";
2750       size_t len = strlen(msg_text1) + strlen(class_loader_name) + strlen(msg_text2) + strlen(name) + 1;
2751       char* message = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, len);
2752       jio_snprintf(message, len, "%s%s%s%s", msg_text1, class_loader_name, msg_text2, name);
2753       THROW_MSG(vmSymbols::java_lang_SecurityException(), message);
2754     }
2755   }
2756   return;
2757 }
2758 
2759 bool InstanceKlass::find_inner_classes_attr(int* ooff, int* noff, TRAPS) const {
2760   constantPoolHandle i_cp(THREAD, constants());
2761   for (InnerClassesIterator iter(this); !iter.done(); iter.next()) {
2762     int ioff = iter.inner_class_info_index();
2763     if (ioff != 0) {
2764       // Check to see if the name matches the class we're looking for
2765       // before attempting to find the class.
2766       if (i_cp->klass_name_at_matches(this, ioff)) {
2767         Klass* inner_klass = i_cp->klass_at(ioff, CHECK_false);
2768         if (this == inner_klass) {
2769           *ooff = iter.outer_class_info_index();
2770           *noff = iter.inner_name_index();
2771           return true;
2772         }
2773       }
2774     }
2775   }
2776   return false;
2777 }
2778 
2779 InstanceKlass* InstanceKlass::compute_enclosing_class(bool* inner_is_member, TRAPS) const {
2780   InstanceKlass* outer_klass = NULL;
2781   *inner_is_member = false;
2782   int ooff = 0, noff = 0;
2783   bool has_inner_classes_attr = find_inner_classes_attr(&ooff, &noff, THREAD);
2784   if (has_inner_classes_attr) {
2785     constantPoolHandle i_cp(THREAD, constants());
2786     if (ooff != 0) {
2787       Klass* ok = i_cp->klass_at(ooff, CHECK_NULL);
2788       outer_klass = InstanceKlass::cast(ok);
2789       *inner_is_member = true;
2790     }
2791     if (NULL == outer_klass) {
2792       // It may be unsafe anonymous; try for that.
2793       int encl_method_class_idx = enclosing_method_class_index();
2794       if (encl_method_class_idx != 0) {
2795         Klass* ok = i_cp->klass_at(encl_method_class_idx, CHECK_NULL);
2796         outer_klass = InstanceKlass::cast(ok);
2797         *inner_is_member = false;
2798       }
2799     }
2800   }
2801 
2802   // If no inner class attribute found for this class.
2803   if (NULL == outer_klass) return NULL;
2804 
2805   // Throws an exception if outer klass has not declared k as an inner klass
2806   // We need evidence that each klass knows about the other, or else
2807   // the system could allow a spoof of an inner class to gain access rights.
2808   Reflection::check_for_inner_class(outer_klass, this, *inner_is_member, CHECK_NULL);
2809   return outer_klass;
2810 }
2811 
2812 jint InstanceKlass::compute_modifier_flags(TRAPS) const {
2813   jint access = access_flags().as_int();
2814 
2815   // But check if it happens to be member class.
2816   InnerClassesIterator iter(this);
2817   for (; !iter.done(); iter.next()) {
2818     int ioff = iter.inner_class_info_index();
2819     // Inner class attribute can be zero, skip it.
2820     // Strange but true:  JVM spec. allows null inner class refs.
2821     if (ioff == 0) continue;
2822 
2823     // only look at classes that are already loaded
2824     // since we are looking for the flags for our self.
2825     Symbol* inner_name = constants()->klass_name_at(ioff);
2826     if (name() == inner_name) {
2827       // This is really a member class.
2828       access = iter.inner_access_flags();
2829       break;
2830     }
2831   }
2832   // Remember to strip ACC_SUPER bit
2833   return (access & (~JVM_ACC_SUPER)) & JVM_ACC_WRITTEN_FLAGS;
2834 }
2835 
2836 jint InstanceKlass::jvmti_class_status() const {
2837   jint result = 0;
2838 
2839   if (is_linked()) {
2840     result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED;
2841   }
2842 
2843   if (is_initialized()) {
2844     assert(is_linked(), "Class status is not consistent");
2845     result |= JVMTI_CLASS_STATUS_INITIALIZED;
2846   }
2847   if (is_in_error_state()) {
2848     result |= JVMTI_CLASS_STATUS_ERROR;
2849   }
2850   return result;
2851 }
2852 
2853 Method* InstanceKlass::method_at_itable(Klass* holder, int index, TRAPS) {
2854   itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2855   int method_table_offset_in_words = ioe->offset()/wordSize;
2856   int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words())
2857                        / itableOffsetEntry::size();
2858 
2859   for (int cnt = 0 ; ; cnt ++, ioe ++) {
2860     // If the interface isn't implemented by the receiver class,
2861     // the VM should throw IncompatibleClassChangeError.
2862     if (cnt >= nof_interfaces) {
2863       ResourceMark rm(THREAD);
2864       stringStream ss;
2865       bool same_module = (module() == holder->module());
2866       ss.print("Receiver class %s does not implement "
2867                "the interface %s defining the method to be called "
2868                "(%s%s%s)",
2869                external_name(), holder->external_name(),
2870                (same_module) ? joint_in_module_of_loader(holder) : class_in_module_of_loader(),
2871                (same_module) ? "" : "; ",
2872                (same_module) ? "" : holder->class_in_module_of_loader());
2873       THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), ss.as_string());
2874     }
2875 
2876     Klass* ik = ioe->interface_klass();
2877     if (ik == holder) break;
2878   }
2879 
2880   itableMethodEntry* ime = ioe->first_method_entry(this);
2881   Method* m = ime[index].method();
2882   if (m == NULL) {
2883     THROW_NULL(vmSymbols::java_lang_AbstractMethodError());
2884   }
2885   return m;
2886 }
2887 
2888 
2889 #if INCLUDE_JVMTI
2890 // update default_methods for redefineclasses for methods that are
2891 // not yet in the vtable due to concurrent subclass define and superinterface
2892 // redefinition
2893 // Note: those in the vtable, should have been updated via adjust_method_entries
2894 void InstanceKlass::adjust_default_methods(InstanceKlass* holder, bool* trace_name_printed) {
2895   // search the default_methods for uses of either obsolete or EMCP methods
2896   if (default_methods() != NULL) {
2897     for (int index = 0; index < default_methods()->length(); index ++) {
2898       Method* old_method = default_methods()->at(index);
2899       if (old_method == NULL || old_method->method_holder() != holder || !old_method->is_old()) {
2900         continue; // skip uninteresting entries
2901       }
2902       assert(!old_method->is_deleted(), "default methods may not be deleted");
2903 
2904       Method* new_method = holder->method_with_idnum(old_method->orig_method_idnum());
2905 
2906       assert(new_method != NULL, "method_with_idnum() should not be NULL");
2907       assert(old_method != new_method, "sanity check");
2908 
2909       default_methods()->at_put(index, new_method);
2910       if (log_is_enabled(Info, redefine, class, update)) {
2911         ResourceMark rm;
2912         if (!(*trace_name_printed)) {
2913           log_info(redefine, class, update)
2914             ("adjust: klassname=%s default methods from name=%s",
2915              external_name(), old_method->method_holder()->external_name());
2916           *trace_name_printed = true;
2917         }
2918         log_debug(redefine, class, update, vtables)
2919           ("default method update: %s(%s) ",
2920            new_method->name()->as_C_string(), new_method->signature()->as_C_string());
2921       }
2922     }
2923   }
2924 }
2925 #endif // INCLUDE_JVMTI
2926 
2927 // On-stack replacement stuff
2928 void InstanceKlass::add_osr_nmethod(nmethod* n) {
2929   // only one compilation can be active
2930   {
2931     // This is a short non-blocking critical region, so the no safepoint check is ok.
2932     MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2933     assert(n->is_osr_method(), "wrong kind of nmethod");
2934     n->set_osr_link(osr_nmethods_head());
2935     set_osr_nmethods_head(n);
2936     // Raise the highest osr level if necessary
2937     if (TieredCompilation) {
2938       Method* m = n->method();
2939       m->set_highest_osr_comp_level(MAX2(m->highest_osr_comp_level(), n->comp_level()));
2940     }
2941   }
2942 
2943   // Get rid of the osr methods for the same bci that have lower levels.
2944   if (TieredCompilation) {
2945     for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) {
2946       nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true);
2947       if (inv != NULL && inv->is_in_use()) {
2948         inv->make_not_entrant();
2949       }
2950     }
2951   }
2952 }
2953 
2954 // Remove osr nmethod from the list. Return true if found and removed.
2955 bool InstanceKlass::remove_osr_nmethod(nmethod* n) {
2956   // This is a short non-blocking critical region, so the no safepoint check is ok.
2957   MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2958   assert(n->is_osr_method(), "wrong kind of nmethod");
2959   nmethod* last = NULL;
2960   nmethod* cur  = osr_nmethods_head();
2961   int max_level = CompLevel_none;  // Find the max comp level excluding n
2962   Method* m = n->method();
2963   // Search for match
2964   bool found = false;
2965   while(cur != NULL && cur != n) {
2966     if (TieredCompilation && m == cur->method()) {
2967       // Find max level before n
2968       max_level = MAX2(max_level, cur->comp_level());
2969     }
2970     last = cur;
2971     cur = cur->osr_link();
2972   }
2973   nmethod* next = NULL;
2974   if (cur == n) {
2975     found = true;
2976     next = cur->osr_link();
2977     if (last == NULL) {
2978       // Remove first element
2979       set_osr_nmethods_head(next);
2980     } else {
2981       last->set_osr_link(next);
2982     }
2983   }
2984   n->set_osr_link(NULL);
2985   if (TieredCompilation) {
2986     cur = next;
2987     while (cur != NULL) {
2988       // Find max level after n
2989       if (m == cur->method()) {
2990         max_level = MAX2(max_level, cur->comp_level());
2991       }
2992       cur = cur->osr_link();
2993     }
2994     m->set_highest_osr_comp_level(max_level);
2995   }
2996   return found;
2997 }
2998 
2999 int InstanceKlass::mark_osr_nmethods(const Method* m) {
3000   // This is a short non-blocking critical region, so the no safepoint check is ok.
3001   MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
3002   nmethod* osr = osr_nmethods_head();
3003   int found = 0;
3004   while (osr != NULL) {
3005     assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
3006     if (osr->method() == m) {
3007       osr->mark_for_deoptimization();
3008       found++;
3009     }
3010     osr = osr->osr_link();
3011   }
3012   return found;
3013 }
3014 
3015 nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const {
3016   // This is a short non-blocking critical region, so the no safepoint check is ok.
3017   MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
3018   nmethod* osr = osr_nmethods_head();
3019   nmethod* best = NULL;
3020   while (osr != NULL) {
3021     assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
3022     // There can be a time when a c1 osr method exists but we are waiting
3023     // for a c2 version. When c2 completes its osr nmethod we will trash
3024     // the c1 version and only be able to find the c2 version. However
3025     // while we overflow in the c1 code at back branches we don't want to
3026     // try and switch to the same code as we are already running
3027 
3028     if (osr->method() == m &&
3029         (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) {
3030       if (match_level) {
3031         if (osr->comp_level() == comp_level) {
3032           // Found a match - return it.
3033           return osr;
3034         }
3035       } else {
3036         if (best == NULL || (osr->comp_level() > best->comp_level())) {
3037           if (osr->comp_level() == CompLevel_highest_tier) {
3038             // Found the best possible - return it.
3039             return osr;
3040           }
3041           best = osr;
3042         }
3043       }
3044     }
3045     osr = osr->osr_link();
3046   }
3047   if (best != NULL && best->comp_level() >= comp_level && match_level == false) {
3048     return best;
3049   }
3050   return NULL;
3051 }
3052 
3053 // -----------------------------------------------------------------------------------------------------
3054 // Printing
3055 
3056 #ifndef PRODUCT
3057 
3058 #define BULLET  " - "
3059 
3060 static const char* state_names[] = {
3061   "allocated", "loaded", "linked", "being_initialized", "fully_initialized", "initialization_error"
3062 };
3063 
3064 static void print_vtable(intptr_t* start, int len, outputStream* st) {
3065   for (int i = 0; i < len; i++) {
3066     intptr_t e = start[i];
3067     st->print("%d : " INTPTR_FORMAT, i, e);
3068     if (e != 0 && ((Metadata*)e)->is_metaspace_object()) {
3069       st->print(" ");
3070       ((Metadata*)e)->print_value_on(st);
3071     }
3072     st->cr();
3073   }
3074 }
3075 
3076 static void print_vtable(vtableEntry* start, int len, outputStream* st) {
3077   return print_vtable(reinterpret_cast<intptr_t*>(start), len, st);
3078 }
3079 
3080 void InstanceKlass::print_on(outputStream* st) const {
3081   assert(is_klass(), "must be klass");
3082   Klass::print_on(st);
3083 
3084   st->print(BULLET"instance size:     %d", size_helper());                        st->cr();
3085   st->print(BULLET"klass size:        %d", size());                               st->cr();
3086   st->print(BULLET"access:            "); access_flags().print_on(st);            st->cr();
3087   st->print(BULLET"state:             "); st->print_cr("%s", state_names[_init_state]);
3088   st->print(BULLET"name:              "); name()->print_value_on(st);             st->cr();
3089   st->print(BULLET"super:             "); Metadata::print_value_on_maybe_null(st, super()); st->cr();
3090   st->print(BULLET"sub:               ");
3091   Klass* sub = subklass();
3092   int n;
3093   for (n = 0; sub != NULL; n++, sub = sub->next_sibling()) {
3094     if (n < MaxSubklassPrintSize) {
3095       sub->print_value_on(st);
3096       st->print("   ");
3097     }
3098   }
3099   if (n >= MaxSubklassPrintSize) st->print("(" INTX_FORMAT " more klasses...)", n - MaxSubklassPrintSize);
3100   st->cr();
3101 
3102   if (is_interface()) {
3103     MutexLocker ml(Compile_lock);
3104     st->print_cr(BULLET"nof implementors:  %d", nof_implementors());
3105     if (nof_implementors() == 1) {
3106       st->print_cr(BULLET"implementor:    ");
3107       st->print("   ");
3108       implementor()->print_value_on(st);
3109       st->cr();
3110     }
3111   }
3112 
3113   st->print(BULLET"arrays:            "); Metadata::print_value_on_maybe_null(st, array_klasses()); st->cr();
3114   st->print(BULLET"methods:           "); methods()->print_value_on(st);                  st->cr();
3115   if (Verbose || WizardMode) {
3116     Array<Method*>* method_array = methods();
3117     for (int i = 0; i < method_array->length(); i++) {
3118       st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
3119     }
3120   }
3121   st->print(BULLET"method ordering:   "); method_ordering()->print_value_on(st);      st->cr();
3122   st->print(BULLET"default_methods:   "); default_methods()->print_value_on(st);      st->cr();
3123   if (Verbose && default_methods() != NULL) {
3124     Array<Method*>* method_array = default_methods();
3125     for (int i = 0; i < method_array->length(); i++) {
3126       st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
3127     }
3128   }
3129   if (default_vtable_indices() != NULL) {
3130     st->print(BULLET"default vtable indices:   "); default_vtable_indices()->print_value_on(st);       st->cr();
3131   }
3132   st->print(BULLET"local interfaces:  "); local_interfaces()->print_value_on(st);      st->cr();
3133   st->print(BULLET"trans. interfaces: "); transitive_interfaces()->print_value_on(st); st->cr();
3134   st->print(BULLET"constants:         "); constants()->print_value_on(st);         st->cr();
3135   if (class_loader_data() != NULL) {
3136     st->print(BULLET"class loader data:  ");
3137     class_loader_data()->print_value_on(st);
3138     st->cr();
3139   }
3140   st->print(BULLET"unsafe anonymous host class:        "); Metadata::print_value_on_maybe_null(st, unsafe_anonymous_host()); st->cr();
3141   if (source_file_name() != NULL) {
3142     st->print(BULLET"source file:       ");
3143     source_file_name()->print_value_on(st);
3144     st->cr();
3145   }
3146   if (source_debug_extension() != NULL) {
3147     st->print(BULLET"source debug extension:       ");
3148     st->print("%s", source_debug_extension());
3149     st->cr();
3150   }
3151   st->print(BULLET"class annotations:       "); class_annotations()->print_value_on(st); st->cr();
3152   st->print(BULLET"class type annotations:  "); class_type_annotations()->print_value_on(st); st->cr();
3153   st->print(BULLET"field annotations:       "); fields_annotations()->print_value_on(st); st->cr();
3154   st->print(BULLET"field type annotations:  "); fields_type_annotations()->print_value_on(st); st->cr();
3155   {
3156     bool have_pv = false;
3157     // previous versions are linked together through the InstanceKlass
3158     for (InstanceKlass* pv_node = previous_versions();
3159          pv_node != NULL;
3160          pv_node = pv_node->previous_versions()) {
3161       if (!have_pv)
3162         st->print(BULLET"previous version:  ");
3163       have_pv = true;
3164       pv_node->constants()->print_value_on(st);
3165     }
3166     if (have_pv) st->cr();
3167   }
3168 
3169   if (generic_signature() != NULL) {
3170     st->print(BULLET"generic signature: ");
3171     generic_signature()->print_value_on(st);
3172     st->cr();
3173   }
3174   st->print(BULLET"inner classes:     "); inner_classes()->print_value_on(st);     st->cr();
3175   st->print(BULLET"nest members:     "); nest_members()->print_value_on(st);     st->cr();
3176   if (java_mirror() != NULL) {
3177     st->print(BULLET"java mirror:       ");
3178     java_mirror()->print_value_on(st);
3179     st->cr();
3180   } else {
3181     st->print_cr(BULLET"java mirror:       NULL");
3182   }
3183   st->print(BULLET"vtable length      %d  (start addr: " INTPTR_FORMAT ")", vtable_length(), p2i(start_of_vtable())); st->cr();
3184   if (vtable_length() > 0 && (Verbose || WizardMode))  print_vtable(start_of_vtable(), vtable_length(), st);
3185   st->print(BULLET"itable length      %d (start addr: " INTPTR_FORMAT ")", itable_length(), p2i(start_of_itable())); st->cr();
3186   if (itable_length() > 0 && (Verbose || WizardMode))  print_vtable(start_of_itable(), itable_length(), st);
3187   st->print_cr(BULLET"---- static fields (%d words):", static_field_size());
3188   FieldPrinter print_static_field(st);
3189   ((InstanceKlass*)this)->do_local_static_fields(&print_static_field);
3190   st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size());
3191   FieldPrinter print_nonstatic_field(st);
3192   InstanceKlass* ik = const_cast<InstanceKlass*>(this);
3193   ik->do_nonstatic_fields(&print_nonstatic_field);
3194 
3195   st->print(BULLET"non-static oop maps: ");
3196   OopMapBlock* map     = start_of_nonstatic_oop_maps();
3197   OopMapBlock* end_map = map + nonstatic_oop_map_count();
3198   while (map < end_map) {
3199     st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1));
3200     map++;
3201   }
3202   st->cr();
3203 }
3204 
3205 #endif //PRODUCT
3206 
3207 void InstanceKlass::print_value_on(outputStream* st) const {
3208   assert(is_klass(), "must be klass");
3209   if (Verbose || WizardMode)  access_flags().print_on(st);
3210   name()->print_value_on(st);
3211 }
3212 
3213 #ifndef PRODUCT
3214 
3215 void FieldPrinter::do_field(fieldDescriptor* fd) {
3216   _st->print(BULLET);
3217    if (_obj == NULL) {
3218      fd->print_on(_st);
3219      _st->cr();
3220    } else {
3221      fd->print_on_for(_st, _obj);
3222      _st->cr();
3223    }
3224 }
3225 
3226 
3227 void InstanceKlass::oop_print_on(oop obj, outputStream* st) {
3228   Klass::oop_print_on(obj, st);
3229 
3230   if (this == SystemDictionary::String_klass()) {
3231     typeArrayOop value  = java_lang_String::value(obj);
3232     juint        length = java_lang_String::length(obj);
3233     if (value != NULL &&
3234         value->is_typeArray() &&
3235         length <= (juint) value->length()) {
3236       st->print(BULLET"string: ");
3237       java_lang_String::print(obj, st);
3238       st->cr();
3239       if (!WizardMode)  return;  // that is enough
3240     }
3241   }
3242 
3243   st->print_cr(BULLET"---- fields (total size %d words):", oop_size(obj));
3244   FieldPrinter print_field(st, obj);
3245   do_nonstatic_fields(&print_field);
3246 
3247   if (this == SystemDictionary::Class_klass()) {
3248     st->print(BULLET"signature: ");
3249     java_lang_Class::print_signature(obj, st);
3250     st->cr();
3251     Klass* mirrored_klass = java_lang_Class::as_Klass(obj);
3252     st->print(BULLET"fake entry for mirror: ");
3253     Metadata::print_value_on_maybe_null(st, mirrored_klass);
3254     st->cr();
3255     Klass* array_klass = java_lang_Class::array_klass_acquire(obj);
3256     st->print(BULLET"fake entry for array: ");
3257     Metadata::print_value_on_maybe_null(st, array_klass);
3258     st->cr();
3259     st->print_cr(BULLET"fake entry for oop_size: %d", java_lang_Class::oop_size(obj));
3260     st->print_cr(BULLET"fake entry for static_oop_field_count: %d", java_lang_Class::static_oop_field_count(obj));
3261     Klass* real_klass = java_lang_Class::as_Klass(obj);
3262     if (real_klass != NULL && real_klass->is_instance_klass()) {
3263       InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field);
3264     }
3265   } else if (this == SystemDictionary::MethodType_klass()) {
3266     st->print(BULLET"signature: ");
3267     java_lang_invoke_MethodType::print_signature(obj, st);
3268     st->cr();
3269   }
3270 }
3271 
3272 bool InstanceKlass::verify_itable_index(int i) {
3273   int method_count = klassItable::method_count_for_interface(this);
3274   assert(i >= 0 && i < method_count, "index out of bounds");
3275   return true;
3276 }
3277 
3278 #endif //PRODUCT
3279 
3280 void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) {
3281   st->print("a ");
3282   name()->print_value_on(st);
3283   obj->print_address_on(st);
3284   if (this == SystemDictionary::String_klass()
3285       && java_lang_String::value(obj) != NULL) {
3286     ResourceMark rm;
3287     int len = java_lang_String::length(obj);
3288     int plen = (len < 24 ? len : 12);
3289     char* str = java_lang_String::as_utf8_string(obj, 0, plen);
3290     st->print(" = \"%s\"", str);
3291     if (len > plen)
3292       st->print("...[%d]", len);
3293   } else if (this == SystemDictionary::Class_klass()) {
3294     Klass* k = java_lang_Class::as_Klass(obj);
3295     st->print(" = ");
3296     if (k != NULL) {
3297       k->print_value_on(st);
3298     } else {
3299       const char* tname = type2name(java_lang_Class::primitive_type(obj));
3300       st->print("%s", tname ? tname : "type?");
3301     }
3302   } else if (this == SystemDictionary::MethodType_klass()) {
3303     st->print(" = ");
3304     java_lang_invoke_MethodType::print_signature(obj, st);
3305   } else if (java_lang_boxing_object::is_instance(obj)) {
3306     st->print(" = ");
3307     java_lang_boxing_object::print(obj, st);
3308   } else if (this == SystemDictionary::LambdaForm_klass()) {
3309     oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj);
3310     if (vmentry != NULL) {
3311       st->print(" => ");
3312       vmentry->print_value_on(st);
3313     }
3314   } else if (this == SystemDictionary::MemberName_klass()) {
3315     Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj);
3316     if (vmtarget != NULL) {
3317       st->print(" = ");
3318       vmtarget->print_value_on(st);
3319     } else {
3320       java_lang_invoke_MemberName::clazz(obj)->print_value_on(st);
3321       st->print(".");
3322       java_lang_invoke_MemberName::name(obj)->print_value_on(st);
3323     }
3324   }
3325 }
3326 
3327 const char* InstanceKlass::internal_name() const {
3328   return external_name();
3329 }
3330 
3331 void InstanceKlass::print_class_load_logging(ClassLoaderData* loader_data,
3332                                              const char* module_name,
3333                                              const ClassFileStream* cfs) const {
3334   if (!log_is_enabled(Info, class, load)) {
3335     return;
3336   }
3337 
3338   ResourceMark rm;
3339   LogMessage(class, load) msg;
3340   stringStream info_stream;
3341 
3342   // Name and class hierarchy info
3343   info_stream.print("%s", external_name());
3344 
3345   // Source
3346   if (cfs != NULL) {
3347     if (cfs->source() != NULL) {
3348       if (module_name != NULL) {
3349         if (ClassLoader::is_modules_image(cfs->source())) {
3350           info_stream.print(" source: jrt:/%s", module_name);
3351         } else {
3352           info_stream.print(" source: %s", cfs->source());
3353         }
3354       } else {
3355         info_stream.print(" source: %s", cfs->source());
3356       }
3357     } else if (loader_data == ClassLoaderData::the_null_class_loader_data()) {
3358       Thread* THREAD = Thread::current();
3359       Klass* caller =
3360             THREAD->is_Java_thread()
3361                 ? ((JavaThread*)THREAD)->security_get_caller_class(1)
3362                 : NULL;
3363       // caller can be NULL, for example, during a JVMTI VM_Init hook
3364       if (caller != NULL) {
3365         info_stream.print(" source: instance of %s", caller->external_name());
3366       } else {
3367         // source is unknown
3368       }
3369     } else {
3370       oop class_loader = loader_data->class_loader();
3371       info_stream.print(" source: %s", class_loader->klass()->external_name());
3372     }
3373   } else {
3374     info_stream.print(" source: shared objects file");
3375   }
3376 
3377   msg.info("%s", info_stream.as_string());
3378 
3379   if (log_is_enabled(Debug, class, load)) {
3380     stringStream debug_stream;
3381 
3382     // Class hierarchy info
3383     debug_stream.print(" klass: " INTPTR_FORMAT " super: " INTPTR_FORMAT,
3384                        p2i(this),  p2i(superklass()));
3385 
3386     // Interfaces
3387     if (local_interfaces() != NULL && local_interfaces()->length() > 0) {
3388       debug_stream.print(" interfaces:");
3389       int length = local_interfaces()->length();
3390       for (int i = 0; i < length; i++) {
3391         debug_stream.print(" " INTPTR_FORMAT,
3392                            p2i(InstanceKlass::cast(local_interfaces()->at(i))));
3393       }
3394     }
3395 
3396     // Class loader
3397     debug_stream.print(" loader: [");
3398     loader_data->print_value_on(&debug_stream);
3399     debug_stream.print("]");
3400 
3401     // Classfile checksum
3402     if (cfs) {
3403       debug_stream.print(" bytes: %d checksum: %08x",
3404                          cfs->length(),
3405                          ClassLoader::crc32(0, (const char*)cfs->buffer(),
3406                          cfs->length()));
3407     }
3408 
3409     msg.debug("%s", debug_stream.as_string());
3410   }
3411 }
3412 
3413 #if INCLUDE_SERVICES
3414 // Size Statistics
3415 void InstanceKlass::collect_statistics(KlassSizeStats *sz) const {
3416   Klass::collect_statistics(sz);
3417 
3418   sz->_inst_size  = wordSize * size_helper();
3419   sz->_vtab_bytes = wordSize * vtable_length();
3420   sz->_itab_bytes = wordSize * itable_length();
3421   sz->_nonstatic_oopmap_bytes = wordSize * nonstatic_oop_map_size();
3422 
3423   int n = 0;
3424   n += (sz->_methods_array_bytes         = sz->count_array(methods()));
3425   n += (sz->_method_ordering_bytes       = sz->count_array(method_ordering()));
3426   n += (sz->_local_interfaces_bytes      = sz->count_array(local_interfaces()));
3427   n += (sz->_transitive_interfaces_bytes = sz->count_array(transitive_interfaces()));
3428   n += (sz->_fields_bytes                = sz->count_array(fields()));
3429   n += (sz->_inner_classes_bytes         = sz->count_array(inner_classes()));
3430   n += (sz->_nest_members_bytes          = sz->count_array(nest_members()));
3431   sz->_ro_bytes += n;
3432 
3433   const ConstantPool* cp = constants();
3434   if (cp) {
3435     cp->collect_statistics(sz);
3436   }
3437 
3438   const Annotations* anno = annotations();
3439   if (anno) {
3440     anno->collect_statistics(sz);
3441   }
3442 
3443   const Array<Method*>* methods_array = methods();
3444   if (methods()) {
3445     for (int i = 0; i < methods_array->length(); i++) {
3446       Method* method = methods_array->at(i);
3447       if (method) {
3448         sz->_method_count ++;
3449         method->collect_statistics(sz);
3450       }
3451     }
3452   }
3453 }
3454 #endif // INCLUDE_SERVICES
3455 
3456 // Verification
3457 
3458 class VerifyFieldClosure: public BasicOopIterateClosure {
3459  protected:
3460   template <class T> void do_oop_work(T* p) {
3461     oop obj = RawAccess<>::oop_load(p);
3462     if (!oopDesc::is_oop_or_null(obj)) {
3463       tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p2i(p), p2i(obj));
3464       Universe::print_on(tty);
3465       guarantee(false, "boom");
3466     }
3467   }
3468  public:
3469   virtual void do_oop(oop* p)       { VerifyFieldClosure::do_oop_work(p); }
3470   virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); }
3471 };
3472 
3473 void InstanceKlass::verify_on(outputStream* st) {
3474 #ifndef PRODUCT
3475   // Avoid redundant verifies, this really should be in product.
3476   if (_verify_count == Universe::verify_count()) return;
3477   _verify_count = Universe::verify_count();
3478 #endif
3479 
3480   // Verify Klass
3481   Klass::verify_on(st);
3482 
3483   // Verify that klass is present in ClassLoaderData
3484   guarantee(class_loader_data()->contains_klass(this),
3485             "this class isn't found in class loader data");
3486 
3487   // Verify vtables
3488   if (is_linked()) {
3489     // $$$ This used to be done only for m/s collections.  Doing it
3490     // always seemed a valid generalization.  (DLD -- 6/00)
3491     vtable().verify(st);
3492   }
3493 
3494   // Verify first subklass
3495   if (subklass() != NULL) {
3496     guarantee(subklass()->is_klass(), "should be klass");
3497   }
3498 
3499   // Verify siblings
3500   Klass* super = this->super();
3501   Klass* sib = next_sibling();
3502   if (sib != NULL) {
3503     if (sib == this) {
3504       fatal("subclass points to itself " PTR_FORMAT, p2i(sib));
3505     }
3506 
3507     guarantee(sib->is_klass(), "should be klass");
3508     guarantee(sib->super() == super, "siblings should have same superklass");
3509   }
3510 
3511   // Verify implementor fields requires the Compile_lock, but this is sometimes
3512   // called inside a safepoint, so don't verify.
3513 
3514   // Verify local interfaces
3515   if (local_interfaces()) {
3516     Array<InstanceKlass*>* local_interfaces = this->local_interfaces();
3517     for (int j = 0; j < local_interfaces->length(); j++) {
3518       InstanceKlass* e = local_interfaces->at(j);
3519       guarantee(e->is_klass() && e->is_interface(), "invalid local interface");
3520     }
3521   }
3522 
3523   // Verify transitive interfaces
3524   if (transitive_interfaces() != NULL) {
3525     Array<InstanceKlass*>* transitive_interfaces = this->transitive_interfaces();
3526     for (int j = 0; j < transitive_interfaces->length(); j++) {
3527       InstanceKlass* e = transitive_interfaces->at(j);
3528       guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface");
3529     }
3530   }
3531 
3532   // Verify methods
3533   if (methods() != NULL) {
3534     Array<Method*>* methods = this->methods();
3535     for (int j = 0; j < methods->length(); j++) {
3536       guarantee(methods->at(j)->is_method(), "non-method in methods array");
3537     }
3538     for (int j = 0; j < methods->length() - 1; j++) {
3539       Method* m1 = methods->at(j);
3540       Method* m2 = methods->at(j + 1);
3541       guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3542     }
3543   }
3544 
3545   // Verify method ordering
3546   if (method_ordering() != NULL) {
3547     Array<int>* method_ordering = this->method_ordering();
3548     int length = method_ordering->length();
3549     if (JvmtiExport::can_maintain_original_method_order() ||
3550         ((UseSharedSpaces || DumpSharedSpaces) && length != 0)) {
3551       guarantee(length == methods()->length(), "invalid method ordering length");
3552       jlong sum = 0;
3553       for (int j = 0; j < length; j++) {
3554         int original_index = method_ordering->at(j);
3555         guarantee(original_index >= 0, "invalid method ordering index");
3556         guarantee(original_index < length, "invalid method ordering index");
3557         sum += original_index;
3558       }
3559       // Verify sum of indices 0,1,...,length-1
3560       guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum");
3561     } else {
3562       guarantee(length == 0, "invalid method ordering length");
3563     }
3564   }
3565 
3566   // Verify default methods
3567   if (default_methods() != NULL) {
3568     Array<Method*>* methods = this->default_methods();
3569     for (int j = 0; j < methods->length(); j++) {
3570       guarantee(methods->at(j)->is_method(), "non-method in methods array");
3571     }
3572     for (int j = 0; j < methods->length() - 1; j++) {
3573       Method* m1 = methods->at(j);
3574       Method* m2 = methods->at(j + 1);
3575       guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3576     }
3577   }
3578 
3579   // Verify JNI static field identifiers
3580   if (jni_ids() != NULL) {
3581     jni_ids()->verify(this);
3582   }
3583 
3584   // Verify other fields
3585   if (array_klasses() != NULL) {
3586     guarantee(array_klasses()->is_klass(), "should be klass");
3587   }
3588   if (constants() != NULL) {
3589     guarantee(constants()->is_constantPool(), "should be constant pool");
3590   }
3591   const Klass* anonymous_host = unsafe_anonymous_host();
3592   if (anonymous_host != NULL) {
3593     guarantee(anonymous_host->is_klass(), "should be klass");
3594   }
3595 }
3596 
3597 void InstanceKlass::oop_verify_on(oop obj, outputStream* st) {
3598   Klass::oop_verify_on(obj, st);
3599   VerifyFieldClosure blk;
3600   obj->oop_iterate(&blk);
3601 }
3602 
3603 
3604 // JNIid class for jfieldIDs only
3605 // Note to reviewers:
3606 // These JNI functions are just moved over to column 1 and not changed
3607 // in the compressed oops workspace.
3608 JNIid::JNIid(Klass* holder, int offset, JNIid* next) {
3609   _holder = holder;
3610   _offset = offset;
3611   _next = next;
3612   debug_only(_is_static_field_id = false;)
3613 }
3614 
3615 
3616 JNIid* JNIid::find(int offset) {
3617   JNIid* current = this;
3618   while (current != NULL) {
3619     if (current->offset() == offset) return current;
3620     current = current->next();
3621   }
3622   return NULL;
3623 }
3624 
3625 void JNIid::deallocate(JNIid* current) {
3626   while (current != NULL) {
3627     JNIid* next = current->next();
3628     delete current;
3629     current = next;
3630   }
3631 }
3632 
3633 
3634 void JNIid::verify(Klass* holder) {
3635   int first_field_offset  = InstanceMirrorKlass::offset_of_static_fields();
3636   int end_field_offset;
3637   end_field_offset = first_field_offset + (InstanceKlass::cast(holder)->static_field_size() * wordSize);
3638 
3639   JNIid* current = this;
3640   while (current != NULL) {
3641     guarantee(current->holder() == holder, "Invalid klass in JNIid");
3642 #ifdef ASSERT
3643     int o = current->offset();
3644     if (current->is_static_field_id()) {
3645       guarantee(o >= first_field_offset  && o < end_field_offset,  "Invalid static field offset in JNIid");
3646     }
3647 #endif
3648     current = current->next();
3649   }
3650 }
3651 
3652 #ifdef ASSERT
3653 void InstanceKlass::set_init_state(ClassState state) {
3654   bool good_state = is_shared() ? (_init_state <= state)
3655                                                : (_init_state < state);
3656   assert(good_state || state == allocated, "illegal state transition");
3657   _init_state = (u1)state;
3658 }
3659 #endif
3660 
3661 #if INCLUDE_JVMTI
3662 
3663 // RedefineClasses() support for previous versions
3664 
3665 // Globally, there is at least one previous version of a class to walk
3666 // during class unloading, which is saved because old methods in the class
3667 // are still running.   Otherwise the previous version list is cleaned up.
3668 bool InstanceKlass::_has_previous_versions = false;
3669 
3670 // Returns true if there are previous versions of a class for class
3671 // unloading only. Also resets the flag to false. purge_previous_version
3672 // will set the flag to true if there are any left, i.e., if there's any
3673 // work to do for next time. This is to avoid the expensive code cache
3674 // walk in CLDG::clean_deallocate_lists().
3675 bool InstanceKlass::has_previous_versions_and_reset() {
3676   bool ret = _has_previous_versions;
3677   log_trace(redefine, class, iklass, purge)("Class unloading: has_previous_versions = %s",
3678      ret ? "true" : "false");
3679   _has_previous_versions = false;
3680   return ret;
3681 }
3682 
3683 // Purge previous versions before adding new previous versions of the class and
3684 // during class unloading.
3685 void InstanceKlass::purge_previous_version_list() {
3686   assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
3687   assert(has_been_redefined(), "Should only be called for main class");
3688 
3689   // Quick exit.
3690   if (previous_versions() == NULL) {
3691     return;
3692   }
3693 
3694   // This klass has previous versions so see what we can cleanup
3695   // while it is safe to do so.
3696 
3697   int deleted_count = 0;    // leave debugging breadcrumbs
3698   int live_count = 0;
3699   ClassLoaderData* loader_data = class_loader_data();
3700   assert(loader_data != NULL, "should never be null");
3701 
3702   ResourceMark rm;
3703   log_trace(redefine, class, iklass, purge)("%s: previous versions", external_name());
3704 
3705   // previous versions are linked together through the InstanceKlass
3706   InstanceKlass* pv_node = previous_versions();
3707   InstanceKlass* last = this;
3708   int version = 0;
3709 
3710   // check the previous versions list
3711   for (; pv_node != NULL; ) {
3712 
3713     ConstantPool* pvcp = pv_node->constants();
3714     assert(pvcp != NULL, "cp ref was unexpectedly cleared");
3715 
3716     if (!pvcp->on_stack()) {
3717       // If the constant pool isn't on stack, none of the methods
3718       // are executing.  Unlink this previous_version.
3719       // The previous version InstanceKlass is on the ClassLoaderData deallocate list
3720       // so will be deallocated during the next phase of class unloading.
3721       log_trace(redefine, class, iklass, purge)
3722         ("previous version " INTPTR_FORMAT " is dead.", p2i(pv_node));
3723       // For debugging purposes.
3724       pv_node->set_is_scratch_class();
3725       // Unlink from previous version list.
3726       assert(pv_node->class_loader_data() == loader_data, "wrong loader_data");
3727       InstanceKlass* next = pv_node->previous_versions();
3728       pv_node->link_previous_versions(NULL);   // point next to NULL
3729       last->link_previous_versions(next);
3730       // Add to the deallocate list after unlinking
3731       loader_data->add_to_deallocate_list(pv_node);
3732       pv_node = next;
3733       deleted_count++;
3734       version++;
3735       continue;
3736     } else {
3737       log_trace(redefine, class, iklass, purge)("previous version " INTPTR_FORMAT " is alive", p2i(pv_node));
3738       assert(pvcp->pool_holder() != NULL, "Constant pool with no holder");
3739       guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack");
3740       live_count++;
3741       // found a previous version for next time we do class unloading
3742       _has_previous_versions = true;
3743     }
3744 
3745     // At least one method is live in this previous version.
3746     // Reset dead EMCP methods not to get breakpoints.
3747     // All methods are deallocated when all of the methods for this class are no
3748     // longer running.
3749     Array<Method*>* method_refs = pv_node->methods();
3750     if (method_refs != NULL) {
3751       log_trace(redefine, class, iklass, purge)("previous methods length=%d", method_refs->length());
3752       for (int j = 0; j < method_refs->length(); j++) {
3753         Method* method = method_refs->at(j);
3754 
3755         if (!method->on_stack()) {
3756           // no breakpoints for non-running methods
3757           if (method->is_running_emcp()) {
3758             method->set_running_emcp(false);
3759           }
3760         } else {
3761           assert (method->is_obsolete() || method->is_running_emcp(),
3762                   "emcp method cannot run after emcp bit is cleared");
3763           log_trace(redefine, class, iklass, purge)
3764             ("purge: %s(%s): prev method @%d in version @%d is alive",
3765              method->name()->as_C_string(), method->signature()->as_C_string(), j, version);
3766         }
3767       }
3768     }
3769     // next previous version
3770     last = pv_node;
3771     pv_node = pv_node->previous_versions();
3772     version++;
3773   }
3774   log_trace(redefine, class, iklass, purge)
3775     ("previous version stats: live=%d, deleted=%d", live_count, deleted_count);
3776 }
3777 
3778 void InstanceKlass::mark_newly_obsolete_methods(Array<Method*>* old_methods,
3779                                                 int emcp_method_count) {
3780   int obsolete_method_count = old_methods->length() - emcp_method_count;
3781 
3782   if (emcp_method_count != 0 && obsolete_method_count != 0 &&
3783       _previous_versions != NULL) {
3784     // We have a mix of obsolete and EMCP methods so we have to
3785     // clear out any matching EMCP method entries the hard way.
3786     int local_count = 0;
3787     for (int i = 0; i < old_methods->length(); i++) {
3788       Method* old_method = old_methods->at(i);
3789       if (old_method->is_obsolete()) {
3790         // only obsolete methods are interesting
3791         Symbol* m_name = old_method->name();
3792         Symbol* m_signature = old_method->signature();
3793 
3794         // previous versions are linked together through the InstanceKlass
3795         int j = 0;
3796         for (InstanceKlass* prev_version = _previous_versions;
3797              prev_version != NULL;
3798              prev_version = prev_version->previous_versions(), j++) {
3799 
3800           Array<Method*>* method_refs = prev_version->methods();
3801           for (int k = 0; k < method_refs->length(); k++) {
3802             Method* method = method_refs->at(k);
3803 
3804             if (!method->is_obsolete() &&
3805                 method->name() == m_name &&
3806                 method->signature() == m_signature) {
3807               // The current RedefineClasses() call has made all EMCP
3808               // versions of this method obsolete so mark it as obsolete
3809               log_trace(redefine, class, iklass, add)
3810                 ("%s(%s): flush obsolete method @%d in version @%d",
3811                  m_name->as_C_string(), m_signature->as_C_string(), k, j);
3812 
3813               method->set_is_obsolete();
3814               break;
3815             }
3816           }
3817 
3818           // The previous loop may not find a matching EMCP method, but
3819           // that doesn't mean that we can optimize and not go any
3820           // further back in the PreviousVersion generations. The EMCP
3821           // method for this generation could have already been made obsolete,
3822           // but there still may be an older EMCP method that has not
3823           // been made obsolete.
3824         }
3825 
3826         if (++local_count >= obsolete_method_count) {
3827           // no more obsolete methods so bail out now
3828           break;
3829         }
3830       }
3831     }
3832   }
3833 }
3834 
3835 // Save the scratch_class as the previous version if any of the methods are running.
3836 // The previous_versions are used to set breakpoints in EMCP methods and they are
3837 // also used to clean MethodData links to redefined methods that are no longer running.
3838 void InstanceKlass::add_previous_version(InstanceKlass* scratch_class,
3839                                          int emcp_method_count) {
3840   assert(Thread::current()->is_VM_thread(),
3841          "only VMThread can add previous versions");
3842 
3843   ResourceMark rm;
3844   log_trace(redefine, class, iklass, add)
3845     ("adding previous version ref for %s, EMCP_cnt=%d", scratch_class->external_name(), emcp_method_count);
3846 
3847   // Clean out old previous versions for this class
3848   purge_previous_version_list();
3849 
3850   // Mark newly obsolete methods in remaining previous versions.  An EMCP method from
3851   // a previous redefinition may be made obsolete by this redefinition.
3852   Array<Method*>* old_methods = scratch_class->methods();
3853   mark_newly_obsolete_methods(old_methods, emcp_method_count);
3854 
3855   // If the constant pool for this previous version of the class
3856   // is not marked as being on the stack, then none of the methods
3857   // in this previous version of the class are on the stack so
3858   // we don't need to add this as a previous version.
3859   ConstantPool* cp_ref = scratch_class->constants();
3860   if (!cp_ref->on_stack()) {
3861     log_trace(redefine, class, iklass, add)("scratch class not added; no methods are running");
3862     // For debugging purposes.
3863     scratch_class->set_is_scratch_class();
3864     scratch_class->class_loader_data()->add_to_deallocate_list(scratch_class);
3865     return;
3866   }
3867 
3868   if (emcp_method_count != 0) {
3869     // At least one method is still running, check for EMCP methods
3870     for (int i = 0; i < old_methods->length(); i++) {
3871       Method* old_method = old_methods->at(i);
3872       if (!old_method->is_obsolete() && old_method->on_stack()) {
3873         // if EMCP method (not obsolete) is on the stack, mark as EMCP so that
3874         // we can add breakpoints for it.
3875 
3876         // We set the method->on_stack bit during safepoints for class redefinition
3877         // and use this bit to set the is_running_emcp bit.
3878         // After the safepoint, the on_stack bit is cleared and the running emcp
3879         // method may exit.   If so, we would set a breakpoint in a method that
3880         // is never reached, but this won't be noticeable to the programmer.
3881         old_method->set_running_emcp(true);
3882         log_trace(redefine, class, iklass, add)
3883           ("EMCP method %s is on_stack " INTPTR_FORMAT, old_method->name_and_sig_as_C_string(), p2i(old_method));
3884       } else if (!old_method->is_obsolete()) {
3885         log_trace(redefine, class, iklass, add)
3886           ("EMCP method %s is NOT on_stack " INTPTR_FORMAT, old_method->name_and_sig_as_C_string(), p2i(old_method));
3887       }
3888     }
3889   }
3890 
3891   // Add previous version if any methods are still running.
3892   // Set has_previous_version flag for processing during class unloading.
3893   _has_previous_versions = true;
3894   log_trace(redefine, class, iklass, add) ("scratch class added; one of its methods is on_stack.");
3895   assert(scratch_class->previous_versions() == NULL, "shouldn't have a previous version");
3896   scratch_class->link_previous_versions(previous_versions());
3897   link_previous_versions(scratch_class);
3898 } // end add_previous_version()
3899 
3900 #endif // INCLUDE_JVMTI
3901 
3902 Method* InstanceKlass::method_with_idnum(int idnum) {
3903   Method* m = NULL;
3904   if (idnum < methods()->length()) {
3905     m = methods()->at(idnum);
3906   }
3907   if (m == NULL || m->method_idnum() != idnum) {
3908     for (int index = 0; index < methods()->length(); ++index) {
3909       m = methods()->at(index);
3910       if (m->method_idnum() == idnum) {
3911         return m;
3912       }
3913     }
3914     // None found, return null for the caller to handle.
3915     return NULL;
3916   }
3917   return m;
3918 }
3919 
3920 
3921 Method* InstanceKlass::method_with_orig_idnum(int idnum) {
3922   if (idnum >= methods()->length()) {
3923     return NULL;
3924   }
3925   Method* m = methods()->at(idnum);
3926   if (m != NULL && m->orig_method_idnum() == idnum) {
3927     return m;
3928   }
3929   // Obsolete method idnum does not match the original idnum
3930   for (int index = 0; index < methods()->length(); ++index) {
3931     m = methods()->at(index);
3932     if (m->orig_method_idnum() == idnum) {
3933       return m;
3934     }
3935   }
3936   // None found, return null for the caller to handle.
3937   return NULL;
3938 }
3939 
3940 
3941 Method* InstanceKlass::method_with_orig_idnum(int idnum, int version) {
3942   InstanceKlass* holder = get_klass_version(version);
3943   if (holder == NULL) {
3944     return NULL; // The version of klass is gone, no method is found
3945   }
3946   Method* method = holder->method_with_orig_idnum(idnum);
3947   return method;
3948 }
3949 
3950 #if INCLUDE_JVMTI
3951 JvmtiCachedClassFileData* InstanceKlass::get_cached_class_file() {
3952   if (MetaspaceShared::is_in_shared_metaspace(_cached_class_file)) {
3953     // Ignore the archived class stream data
3954     return NULL;
3955   } else {
3956     return _cached_class_file;
3957   }
3958 }
3959 
3960 jint InstanceKlass::get_cached_class_file_len() {
3961   return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file);
3962 }
3963 
3964 unsigned char * InstanceKlass::get_cached_class_file_bytes() {
3965   return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file);
3966 }
3967 
3968 #if INCLUDE_CDS
3969 JvmtiCachedClassFileData* InstanceKlass::get_archived_class_data() {
3970   if (DumpSharedSpaces) {
3971     return _cached_class_file;
3972   } else {
3973     assert(this->is_shared(), "class should be shared");
3974     if (MetaspaceShared::is_in_shared_metaspace(_cached_class_file)) {
3975       return _cached_class_file;
3976     } else {
3977       return NULL;
3978     }
3979   }
3980 }
3981 #endif
3982 #endif