1 /*
   2  * Copyright (c) 1997, 2017, 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 "aot/aotLoader.hpp"
  27 #include "classfile/classFileParser.hpp"
  28 #include "classfile/classFileStream.hpp"
  29 #include "classfile/classLoader.hpp"
  30 #include "classfile/javaClasses.hpp"
  31 #include "classfile/moduleEntry.hpp"
  32 #include "classfile/systemDictionary.hpp"
  33 #include "classfile/systemDictionaryShared.hpp"
  34 #include "classfile/verifier.hpp"
  35 #include "classfile/vmSymbols.hpp"
  36 #include "code/dependencyContext.hpp"
  37 #include "compiler/compileBroker.hpp"
  38 #include "gc/shared/collectedHeap.inline.hpp"
  39 #include "gc/shared/specialized_oop_closures.hpp"
  40 #include "interpreter/oopMapCache.hpp"
  41 #include "interpreter/rewriter.hpp"
  42 #include "jvmtifiles/jvmti.h"
  43 #include "logging/log.hpp"
  44 #include "memory/heapInspection.hpp"
  45 #include "memory/iterator.inline.hpp"
  46 #include "memory/metadataFactory.hpp"
  47 #include "memory/metaspaceShared.hpp"
  48 #include "memory/oopFactory.hpp"
  49 #include "memory/resourceArea.hpp"
  50 #include "oops/fieldStreams.hpp"
  51 #include "oops/instanceClassLoaderKlass.hpp"
  52 #include "oops/instanceKlass.inline.hpp"
  53 #include "oops/instanceMirrorKlass.hpp"
  54 #include "oops/instanceOop.hpp"
  55 #include "oops/klass.inline.hpp"
  56 #include "oops/method.hpp"
  57 #include "oops/oop.inline.hpp"
  58 #include "oops/symbol.hpp"
  59 #include "prims/jvmtiExport.hpp"
  60 #include "prims/jvmtiRedefineClasses.hpp"
  61 #include "prims/jvmtiThreadState.hpp"
  62 #include "prims/methodComparator.hpp"
  63 #include "runtime/atomic.hpp"
  64 #include "runtime/fieldDescriptor.hpp"
  65 #include "runtime/handles.inline.hpp"
  66 #include "runtime/javaCalls.hpp"
  67 #include "runtime/mutexLocker.hpp"
  68 #include "runtime/orderAccess.inline.hpp"
  69 #include "runtime/thread.inline.hpp"
  70 #include "services/classLoadingService.hpp"
  71 #include "services/threadService.hpp"
  72 #include "utilities/dtrace.hpp"
  73 #include "utilities/macros.hpp"
  74 #include "utilities/stringUtils.hpp"
  75 #include "logging/log.hpp"
  76 #ifdef COMPILER1
  77 #include "c1/c1_Compiler.hpp"
  78 #endif
  79 
  80 #ifdef DTRACE_ENABLED
  81 
  82 
  83 #define HOTSPOT_CLASS_INITIALIZATION_required HOTSPOT_CLASS_INITIALIZATION_REQUIRED
  84 #define HOTSPOT_CLASS_INITIALIZATION_recursive HOTSPOT_CLASS_INITIALIZATION_RECURSIVE
  85 #define HOTSPOT_CLASS_INITIALIZATION_concurrent HOTSPOT_CLASS_INITIALIZATION_CONCURRENT
  86 #define HOTSPOT_CLASS_INITIALIZATION_erroneous HOTSPOT_CLASS_INITIALIZATION_ERRONEOUS
  87 #define HOTSPOT_CLASS_INITIALIZATION_super__failed HOTSPOT_CLASS_INITIALIZATION_SUPER_FAILED
  88 #define HOTSPOT_CLASS_INITIALIZATION_clinit HOTSPOT_CLASS_INITIALIZATION_CLINIT
  89 #define HOTSPOT_CLASS_INITIALIZATION_error HOTSPOT_CLASS_INITIALIZATION_ERROR
  90 #define HOTSPOT_CLASS_INITIALIZATION_end HOTSPOT_CLASS_INITIALIZATION_END
  91 #define DTRACE_CLASSINIT_PROBE(type, clss, thread_type)          \
  92   {                                                              \
  93     char* data = NULL;                                           \
  94     int len = 0;                                                 \
  95     Symbol* name = (clss)->name();                               \
  96     if (name != NULL) {                                          \
  97       data = (char*)name->bytes();                               \
  98       len = name->utf8_length();                                 \
  99     }                                                            \
 100     HOTSPOT_CLASS_INITIALIZATION_##type(                         \
 101       data, len, (clss)->class_loader(), thread_type);           \
 102   }
 103 
 104 #define DTRACE_CLASSINIT_PROBE_WAIT(type, clss, thread_type, wait) \
 105   {                                                              \
 106     char* data = NULL;                                           \
 107     int len = 0;                                                 \
 108     Symbol* name = (clss)->name();                               \
 109     if (name != NULL) {                                          \
 110       data = (char*)name->bytes();                               \
 111       len = name->utf8_length();                                 \
 112     }                                                            \
 113     HOTSPOT_CLASS_INITIALIZATION_##type(                         \
 114       data, len, (clss)->class_loader(), thread_type, wait);     \
 115   }
 116 
 117 #else //  ndef DTRACE_ENABLED
 118 
 119 #define DTRACE_CLASSINIT_PROBE(type, clss, thread_type)
 120 #define DTRACE_CLASSINIT_PROBE_WAIT(type, clss, thread_type, wait)
 121 
 122 #endif //  ndef DTRACE_ENABLED
 123 
 124 volatile int InstanceKlass::_total_instanceKlass_count = 0;
 125 
 126 static inline bool is_class_loader(const Symbol* class_name,
 127                                    const ClassFileParser& parser) {
 128   assert(class_name != NULL, "invariant");
 129 
 130   if (class_name == vmSymbols::java_lang_ClassLoader()) {
 131     return true;
 132   }
 133 
 134   if (SystemDictionary::ClassLoader_klass_loaded()) {
 135     const Klass* const super_klass = parser.super_klass();
 136     if (super_klass != NULL) {
 137       if (super_klass->is_subtype_of(SystemDictionary::ClassLoader_klass())) {
 138         return true;
 139       }
 140     }
 141   }
 142   return false;
 143 }
 144 
 145 InstanceKlass* InstanceKlass::allocate_instance_klass(const ClassFileParser& parser, TRAPS) {
 146   const int size = InstanceKlass::size(parser.vtable_size(),
 147                                        parser.itable_size(),
 148                                        nonstatic_oop_map_size(parser.total_oop_map_count()),
 149                                        parser.is_interface(),
 150                                        parser.is_anonymous(),
 151                                        should_store_fingerprint());
 152 
 153   const Symbol* const class_name = parser.class_name();
 154   assert(class_name != NULL, "invariant");
 155   ClassLoaderData* loader_data = parser.loader_data();
 156   assert(loader_data != NULL, "invariant");
 157 
 158   InstanceKlass* ik;
 159 
 160   // Allocation
 161   if (REF_NONE == parser.reference_type()) {
 162     if (class_name == vmSymbols::java_lang_Class()) {
 163       // mirror
 164       ik = new (loader_data, size, THREAD) InstanceMirrorKlass(parser);
 165     }
 166     else if (is_class_loader(class_name, parser)) {
 167       // class loader
 168       ik = new (loader_data, size, THREAD) InstanceClassLoaderKlass(parser);
 169     }
 170     else {
 171       // normal
 172       ik = new (loader_data, size, THREAD) InstanceKlass(parser, InstanceKlass::_misc_kind_other);
 173     }
 174   }
 175   else {
 176     // reference
 177     ik = new (loader_data, size, THREAD) InstanceRefKlass(parser);
 178   }
 179 
 180   // Check for pending exception before adding to the loader data and incrementing
 181   // class count.  Can get OOM here.
 182   if (HAS_PENDING_EXCEPTION) {
 183     return NULL;
 184   }
 185 
 186   assert(ik != NULL, "invariant");
 187 
 188   const bool publicize = !parser.is_internal();
 189 
 190   // Add all classes to our internal class loader list here,
 191   // including classes in the bootstrap (NULL) class loader.
 192   loader_data->add_class(ik, publicize);
 193   Atomic::inc(&_total_instanceKlass_count);
 194 
 195   return ik;
 196 }
 197 
 198 
 199 // copy method ordering from resource area to Metaspace
 200 void InstanceKlass::copy_method_ordering(const intArray* m, TRAPS) {
 201   if (m != NULL) {
 202     // allocate a new array and copy contents (memcpy?)
 203     _method_ordering = MetadataFactory::new_array<int>(class_loader_data(), m->length(), CHECK);
 204     for (int i = 0; i < m->length(); i++) {
 205       _method_ordering->at_put(i, m->at(i));
 206     }
 207   } else {
 208     _method_ordering = Universe::the_empty_int_array();
 209   }
 210 }
 211 
 212 // create a new array of vtable_indices for default methods
 213 Array<int>* InstanceKlass::create_new_default_vtable_indices(int len, TRAPS) {
 214   Array<int>* vtable_indices = MetadataFactory::new_array<int>(class_loader_data(), len, CHECK_NULL);
 215   assert(default_vtable_indices() == NULL, "only create once");
 216   set_default_vtable_indices(vtable_indices);
 217   return vtable_indices;
 218 }
 219 
 220 InstanceKlass::InstanceKlass(const ClassFileParser& parser, unsigned kind) :
 221   _static_field_size(parser.static_field_size()),
 222   _nonstatic_oop_map_size(nonstatic_oop_map_size(parser.total_oop_map_count())),
 223   _itable_len(parser.itable_size()),
 224   _reference_type(parser.reference_type()) {
 225     set_vtable_length(parser.vtable_size());
 226     set_kind(kind);
 227     set_access_flags(parser.access_flags());
 228     set_is_anonymous(parser.is_anonymous());
 229     set_layout_helper(Klass::instance_layout_helper(parser.layout_size(),
 230                                                     false));
 231 
 232     assert(NULL == _methods, "underlying memory not zeroed?");
 233     assert(is_instance_klass(), "is layout incorrect?");
 234     assert(size_helper() == parser.layout_size(), "incorrect size_helper?");
 235 }
 236 
 237 void InstanceKlass::deallocate_methods(ClassLoaderData* loader_data,
 238                                        Array<Method*>* methods) {
 239   if (methods != NULL && methods != Universe::the_empty_method_array() &&
 240       !methods->is_shared()) {
 241     for (int i = 0; i < methods->length(); i++) {
 242       Method* method = methods->at(i);
 243       if (method == NULL) continue;  // maybe null if error processing
 244       // Only want to delete methods that are not executing for RedefineClasses.
 245       // The previous version will point to them so they're not totally dangling
 246       assert (!method->on_stack(), "shouldn't be called with methods on stack");
 247       MetadataFactory::free_metadata(loader_data, method);
 248     }
 249     MetadataFactory::free_array<Method*>(loader_data, methods);
 250   }
 251 }
 252 
 253 void InstanceKlass::deallocate_interfaces(ClassLoaderData* loader_data,
 254                                           const Klass* super_klass,
 255                                           Array<Klass*>* local_interfaces,
 256                                           Array<Klass*>* transitive_interfaces) {
 257   // Only deallocate transitive interfaces if not empty, same as super class
 258   // or same as local interfaces.  See code in parseClassFile.
 259   Array<Klass*>* ti = transitive_interfaces;
 260   if (ti != Universe::the_empty_klass_array() && ti != local_interfaces) {
 261     // check that the interfaces don't come from super class
 262     Array<Klass*>* sti = (super_klass == NULL) ? NULL :
 263                     InstanceKlass::cast(super_klass)->transitive_interfaces();
 264     if (ti != sti && ti != NULL && !ti->is_shared()) {
 265       MetadataFactory::free_array<Klass*>(loader_data, ti);
 266     }
 267   }
 268 
 269   // local interfaces can be empty
 270   if (local_interfaces != Universe::the_empty_klass_array() &&
 271       local_interfaces != NULL && !local_interfaces->is_shared()) {
 272     MetadataFactory::free_array<Klass*>(loader_data, local_interfaces);
 273   }
 274 }
 275 
 276 // This function deallocates the metadata and C heap pointers that the
 277 // InstanceKlass points to.
 278 void InstanceKlass::deallocate_contents(ClassLoaderData* loader_data) {
 279 
 280   // Orphan the mirror first, CMS thinks it's still live.
 281   if (java_mirror() != NULL) {
 282     java_lang_Class::set_klass(java_mirror(), NULL);
 283   }
 284 
 285   // Need to take this class off the class loader data list.
 286   loader_data->remove_class(this);
 287 
 288   // The array_klass for this class is created later, after error handling.
 289   // For class redefinition, we keep the original class so this scratch class
 290   // doesn't have an array class.  Either way, assert that there is nothing
 291   // to deallocate.
 292   assert(array_klasses() == NULL, "array classes shouldn't be created for this class yet");
 293 
 294   // Release C heap allocated data that this might point to, which includes
 295   // reference counting symbol names.
 296   release_C_heap_structures();
 297 
 298   deallocate_methods(loader_data, methods());
 299   set_methods(NULL);
 300 
 301   if (method_ordering() != NULL &&
 302       method_ordering() != Universe::the_empty_int_array() &&
 303       !method_ordering()->is_shared()) {
 304     MetadataFactory::free_array<int>(loader_data, method_ordering());
 305   }
 306   set_method_ordering(NULL);
 307 
 308   // default methods can be empty
 309   if (default_methods() != NULL &&
 310       default_methods() != Universe::the_empty_method_array() &&
 311       !default_methods()->is_shared()) {
 312     MetadataFactory::free_array<Method*>(loader_data, default_methods());
 313   }
 314   // Do NOT deallocate the default methods, they are owned by superinterfaces.
 315   set_default_methods(NULL);
 316 
 317   // default methods vtable indices can be empty
 318   if (default_vtable_indices() != NULL &&
 319       !default_vtable_indices()->is_shared()) {
 320     MetadataFactory::free_array<int>(loader_data, default_vtable_indices());
 321   }
 322   set_default_vtable_indices(NULL);
 323 
 324 
 325   // This array is in Klass, but remove it with the InstanceKlass since
 326   // this place would be the only caller and it can share memory with transitive
 327   // interfaces.
 328   if (secondary_supers() != NULL &&
 329       secondary_supers() != Universe::the_empty_klass_array() &&
 330       secondary_supers() != transitive_interfaces() &&
 331       !secondary_supers()->is_shared()) {
 332     MetadataFactory::free_array<Klass*>(loader_data, secondary_supers());
 333   }
 334   set_secondary_supers(NULL);
 335 
 336   deallocate_interfaces(loader_data, super(), local_interfaces(), transitive_interfaces());
 337   set_transitive_interfaces(NULL);
 338   set_local_interfaces(NULL);
 339 
 340   if (fields() != NULL && !fields()->is_shared()) {
 341     MetadataFactory::free_array<jushort>(loader_data, fields());
 342   }
 343   set_fields(NULL, 0);
 344 
 345   // If a method from a redefined class is using this constant pool, don't
 346   // delete it, yet.  The new class's previous version will point to this.
 347   if (constants() != NULL) {
 348     assert (!constants()->on_stack(), "shouldn't be called if anything is onstack");
 349     if (!constants()->is_shared()) {
 350       MetadataFactory::free_metadata(loader_data, constants());
 351     }
 352     // Delete any cached resolution errors for the constant pool
 353     SystemDictionary::delete_resolution_error(constants());
 354 
 355     set_constants(NULL);
 356   }
 357 
 358   if (inner_classes() != NULL &&
 359       inner_classes() != Universe::the_empty_short_array() &&
 360       !inner_classes()->is_shared()) {
 361     MetadataFactory::free_array<jushort>(loader_data, inner_classes());
 362   }
 363   set_inner_classes(NULL);
 364 
 365   // We should deallocate the Annotations instance if it's not in shared spaces.
 366   if (annotations() != NULL && !annotations()->is_shared()) {
 367     MetadataFactory::free_metadata(loader_data, annotations());
 368   }
 369   set_annotations(NULL);
 370 }
 371 
 372 bool InstanceKlass::should_be_initialized() const {
 373   return !is_initialized();
 374 }
 375 
 376 klassItable* InstanceKlass::itable() const {
 377   return new klassItable(const_cast<InstanceKlass*>(this));
 378 }
 379 
 380 void InstanceKlass::eager_initialize(Thread *thread) {
 381   if (!EagerInitialization) return;
 382 
 383   if (this->is_not_initialized()) {
 384     // abort if the the class has a class initializer
 385     if (this->class_initializer() != NULL) return;
 386 
 387     // abort if it is java.lang.Object (initialization is handled in genesis)
 388     Klass* super = this->super();
 389     if (super == NULL) return;
 390 
 391     // abort if the super class should be initialized
 392     if (!InstanceKlass::cast(super)->is_initialized()) return;
 393 
 394     // call body to expose the this pointer
 395     eager_initialize_impl(this);

 396   }
 397 }
 398 
 399 // JVMTI spec thinks there are signers and protection domain in the
 400 // instanceKlass.  These accessors pretend these fields are there.
 401 // The hprof specification also thinks these fields are in InstanceKlass.
 402 oop InstanceKlass::protection_domain() const {
 403   // return the protection_domain from the mirror
 404   return java_lang_Class::protection_domain(java_mirror());
 405 }
 406 
 407 // To remove these from requires an incompatible change and CCC request.
 408 objArrayOop InstanceKlass::signers() const {
 409   // return the signers from the mirror
 410   return java_lang_Class::signers(java_mirror());
 411 }
 412 
 413 oop InstanceKlass::init_lock() const {
 414   // return the init lock from the mirror
 415   oop lock = java_lang_Class::init_lock(java_mirror());
 416   // Prevent reordering with any access of initialization state
 417   OrderAccess::loadload();
 418   assert((oop)lock != NULL || !is_not_initialized(), // initialized or in_error state
 419          "only fully initialized state can have a null lock");
 420   return lock;
 421 }
 422 
 423 // Set the initialization lock to null so the object can be GC'ed.  Any racing
 424 // threads to get this lock will see a null lock and will not lock.
 425 // That's okay because they all check for initialized state after getting
 426 // the lock and return.
 427 void InstanceKlass::fence_and_clear_init_lock() {
 428   // make sure previous stores are all done, notably the init_state.
 429   OrderAccess::storestore();
 430   java_lang_Class::set_init_lock(java_mirror(), NULL);
 431   assert(!is_not_initialized(), "class must be initialized now");
 432 }
 433 
 434 void InstanceKlass::eager_initialize_impl(InstanceKlass* this_k) {
 435   EXCEPTION_MARK;
 436   HandleMark hm(THREAD);
 437   Handle init_lock(THREAD, this_k->init_lock());
 438   ObjectLocker ol(init_lock, THREAD, init_lock() != NULL);
 439 
 440   // abort if someone beat us to the initialization
 441   if (!this_k->is_not_initialized()) return;  // note: not equivalent to is_initialized()
 442 
 443   ClassState old_state = this_k->init_state();
 444   link_class_impl(this_k, true, THREAD);
 445   if (HAS_PENDING_EXCEPTION) {
 446     CLEAR_PENDING_EXCEPTION;
 447     // Abort if linking the class throws an exception.
 448 
 449     // Use a test to avoid redundantly resetting the state if there's
 450     // no change.  Set_init_state() asserts that state changes make
 451     // progress, whereas here we might just be spinning in place.
 452     if( old_state != this_k->_init_state )
 453       this_k->set_init_state (old_state);
 454   } else {
 455     // linking successfull, mark class as initialized
 456     this_k->set_init_state (fully_initialized);
 457     this_k->fence_and_clear_init_lock();
 458     // trace
 459     if (log_is_enabled(Info, class, init)) {
 460       ResourceMark rm(THREAD);
 461       log_info(class, init)("[Initialized %s without side effects]", this_k->external_name());
 462     }
 463   }
 464 }
 465 
 466 
 467 // See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization
 468 // process. The step comments refers to the procedure described in that section.
 469 // Note: implementation moved to static method to expose the this pointer.
 470 void InstanceKlass::initialize(TRAPS) {
 471   if (this->should_be_initialized()) {
 472     initialize_impl(this, CHECK);

 473     // Note: at this point the class may be initialized
 474     //       OR it may be in the state of being initialized
 475     //       in case of recursive initialization!
 476   } else {
 477     assert(is_initialized(), "sanity check");
 478   }
 479 }
 480 
 481 
 482 bool InstanceKlass::verify_code(
 483     InstanceKlass* this_k, bool throw_verifyerror, TRAPS) {
 484   // 1) Verify the bytecodes
 485   Verifier::Mode mode =
 486     throw_verifyerror ? Verifier::ThrowException : Verifier::NoException;
 487   return Verifier::verify(this_k, mode, this_k->should_verify_class(), THREAD);
 488 }
 489 
 490 
 491 // Used exclusively by the shared spaces dump mechanism to prevent
 492 // classes mapped into the shared regions in new VMs from appearing linked.
 493 
 494 void InstanceKlass::unlink_class() {
 495   assert(is_linked(), "must be linked");
 496   _init_state = loaded;
 497 }
 498 
 499 void InstanceKlass::link_class(TRAPS) {
 500   assert(is_loaded(), "must be loaded");
 501   if (!is_linked()) {
 502     link_class_impl(this, true, CHECK);

 503   }
 504 }
 505 
 506 // Called to verify that a class can link during initialization, without
 507 // throwing a VerifyError.
 508 bool InstanceKlass::link_class_or_fail(TRAPS) {
 509   assert(is_loaded(), "must be loaded");
 510   if (!is_linked()) {
 511     link_class_impl(this, false, CHECK_false);

 512   }
 513   return is_linked();
 514 }
 515 
 516 bool InstanceKlass::link_class_impl(
 517     InstanceKlass* this_k, bool throw_verifyerror, TRAPS) {
 518   if (DumpSharedSpaces && this_k->is_in_error_state()) {
 519     // This is for CDS dumping phase only -- we use the in_error_state to indicate that
 520     // the class has failed verification. Throwing the NoClassDefFoundError here is just
 521     // a convenient way to stop repeat attempts to verify the same (bad) class.
 522     //
 523     // Note that the NoClassDefFoundError is not part of the JLS, and should not be thrown
 524     // if we are executing Java code. This is not a problem for CDS dumping phase since
 525     // it doesn't execute any Java code.
 526     ResourceMark rm(THREAD);
 527     THROW_MSG_(vmSymbols::java_lang_NoClassDefFoundError(),
 528                this_k->external_name(), false);
 529   }
 530   // return if already verified
 531   if (this_k->is_linked()) {
 532     return true;
 533   }
 534 
 535   // Timing
 536   // timer handles recursion
 537   assert(THREAD->is_Java_thread(), "non-JavaThread in link_class_impl");
 538   JavaThread* jt = (JavaThread*)THREAD;
 539 
 540   // link super class before linking this class
 541   Klass* super = this_k->super();
 542   if (super != NULL) {
 543     if (super->is_interface()) {  // check if super class is an interface
 544       ResourceMark rm(THREAD);
 545       Exceptions::fthrow(
 546         THREAD_AND_LOCATION,
 547         vmSymbols::java_lang_IncompatibleClassChangeError(),
 548         "class %s has interface %s as super class",
 549         this_k->external_name(),
 550         super->external_name()
 551       );
 552       return false;
 553     }
 554 
 555     InstanceKlass* ik_super = InstanceKlass::cast(super);
 556     link_class_impl(ik_super, throw_verifyerror, CHECK_false);
 557   }
 558 
 559   // link all interfaces implemented by this class before linking this class
 560   Array<Klass*>* interfaces = this_k->local_interfaces();
 561   int num_interfaces = interfaces->length();
 562   for (int index = 0; index < num_interfaces; index++) {
 563     InstanceKlass* interk = InstanceKlass::cast(interfaces->at(index));
 564     link_class_impl(interk, throw_verifyerror, CHECK_false);
 565   }
 566 
 567   // in case the class is linked in the process of linking its superclasses
 568   if (this_k->is_linked()) {
 569     return true;
 570   }
 571 
 572   // trace only the link time for this klass that includes
 573   // the verification time
 574   PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(),
 575                              ClassLoader::perf_class_link_selftime(),
 576                              ClassLoader::perf_classes_linked(),
 577                              jt->get_thread_stat()->perf_recursion_counts_addr(),
 578                              jt->get_thread_stat()->perf_timers_addr(),
 579                              PerfClassTraceTime::CLASS_LINK);
 580 
 581   // verification & rewriting
 582   {
 583     HandleMark hm(THREAD);
 584     Handle init_lock(THREAD, this_k->init_lock());
 585     ObjectLocker ol(init_lock, THREAD, init_lock() != NULL);
 586     // rewritten will have been set if loader constraint error found
 587     // on an earlier link attempt
 588     // don't verify or rewrite if already rewritten
 589     //
 590 
 591     if (!this_k->is_linked()) {
 592       if (!this_k->is_rewritten()) {
 593         {
 594           bool verify_ok = verify_code(this_k, throw_verifyerror, THREAD);
 595           if (!verify_ok) {
 596             return false;
 597           }
 598         }
 599 
 600         // Just in case a side-effect of verify linked this class already
 601         // (which can sometimes happen since the verifier loads classes
 602         // using custom class loaders, which are free to initialize things)
 603         if (this_k->is_linked()) {
 604           return true;
 605         }
 606 
 607         // also sets rewritten
 608         this_k->rewrite_class(CHECK_false);
 609       } else if (this_k->is_shared()) {
 610         SystemDictionaryShared::check_verification_constraints(this_k, CHECK_false);
 611       }
 612 
 613       // relocate jsrs and link methods after they are all rewritten
 614       this_k->link_methods(CHECK_false);
 615 
 616       // Initialize the vtable and interface table after
 617       // methods have been rewritten since rewrite may
 618       // fabricate new Method*s.
 619       // also does loader constraint checking
 620       //
 621       // initialize_vtable and initialize_itable need to be rerun for
 622       // a shared class if the class is not loaded by the NULL classloader.
 623       ClassLoaderData * loader_data = this_k->class_loader_data();
 624       if (!(this_k->is_shared() &&
 625             loader_data->is_the_null_class_loader_data())) {
 626         ResourceMark rm(THREAD);
 627         this_k->vtable()->initialize_vtable(true, CHECK_false);
 628         this_k->itable()->initialize_itable(true, CHECK_false);
 629       }
 630 #ifdef ASSERT
 631       else {
 632         ResourceMark rm(THREAD);
 633         this_k->vtable()->verify(tty, true);
 634         // In case itable verification is ever added.
 635         // this_k->itable()->verify(tty, true);
 636       }
 637 #endif
 638       this_k->set_init_state(linked);
 639       if (JvmtiExport::should_post_class_prepare()) {
 640         Thread *thread = THREAD;
 641         assert(thread->is_Java_thread(), "thread->is_Java_thread()");
 642         JvmtiExport::post_class_prepare((JavaThread *) thread, this_k);
 643       }
 644     }
 645   }
 646   return true;
 647 }
 648 
 649 
 650 // Rewrite the byte codes of all of the methods of a class.
 651 // The rewriter must be called exactly once. Rewriting must happen after
 652 // verification but before the first method of the class is executed.
 653 void InstanceKlass::rewrite_class(TRAPS) {
 654   assert(is_loaded(), "must be loaded");
 655   if (is_rewritten()) {
 656     assert(is_shared(), "rewriting an unshared class?");

 657     return;
 658   }
 659   Rewriter::rewrite(this, CHECK);
 660   set_rewritten();
 661 }
 662 
 663 // Now relocate and link method entry points after class is rewritten.
 664 // This is outside is_rewritten flag. In case of an exception, it can be
 665 // executed more than once.
 666 void InstanceKlass::link_methods(TRAPS) {
 667   int len = methods()->length();
 668   for (int i = len-1; i >= 0; i--) {
 669     methodHandle m(THREAD, methods()->at(i));
 670 
 671     // Set up method entry points for compiler and interpreter    .
 672     m->link_method(m, CHECK);
 673   }
 674 }
 675 
 676 // Eagerly initialize superinterfaces that declare default methods (concrete instance: any access)
 677 void InstanceKlass::initialize_super_interfaces(InstanceKlass* this_k, TRAPS) {
 678   assert (this_k->has_nonstatic_concrete_methods(), "caller should have checked this");
 679   for (int i = 0; i < this_k->local_interfaces()->length(); ++i) {
 680     Klass* iface = this_k->local_interfaces()->at(i);
 681     InstanceKlass* ik = InstanceKlass::cast(iface);
 682 
 683     // Initialization is depth first search ie. we start with top of the inheritance tree
 684     // has_nonstatic_concrete_methods drives searching superinterfaces since it
 685     // means has_nonstatic_concrete_methods in its superinterface hierarchy
 686     if (ik->has_nonstatic_concrete_methods()) {
 687       ik->initialize_super_interfaces(ik, CHECK);
 688     }
 689 
 690     // Only initialize() interfaces that "declare" concrete methods.
 691     if (ik->should_be_initialized() && ik->declares_nonstatic_concrete_methods()) {
 692       ik->initialize(CHECK);
 693     }
 694   }
 695 }
 696 
 697 void InstanceKlass::initialize_impl(InstanceKlass* this_k, TRAPS) {
 698   HandleMark hm(THREAD);
 699 
 700   // Make sure klass is linked (verified) before initialization
 701   // A class could already be verified, since it has been reflected upon.
 702   this_k->link_class(CHECK);
 703 
 704   DTRACE_CLASSINIT_PROBE(required, this_k, -1);
 705 
 706   bool wait = false;
 707 
 708   // refer to the JVM book page 47 for description of steps
 709   // Step 1
 710   {
 711     Handle init_lock(THREAD, this_k->init_lock());
 712     ObjectLocker ol(init_lock, THREAD, init_lock() != NULL);
 713 
 714     Thread *self = THREAD; // it's passed the current thread
 715 
 716     // Step 2
 717     // If we were to use wait() instead of waitInterruptibly() then
 718     // we might end up throwing IE from link/symbol resolution sites
 719     // that aren't expected to throw.  This would wreak havoc.  See 6320309.
 720     while(this_k->is_being_initialized() && !this_k->is_reentrant_initialization(self)) {
 721         wait = true;
 722       ol.waitUninterruptibly(CHECK);
 723     }
 724 
 725     // Step 3
 726     if (this_k->is_being_initialized() && this_k->is_reentrant_initialization(self)) {
 727       DTRACE_CLASSINIT_PROBE_WAIT(recursive, this_k, -1,wait);
 728       return;
 729     }
 730 
 731     // Step 4
 732     if (this_k->is_initialized()) {
 733       DTRACE_CLASSINIT_PROBE_WAIT(concurrent, this_k, -1,wait);
 734       return;
 735     }
 736 
 737     // Step 5
 738     if (this_k->is_in_error_state()) {
 739       DTRACE_CLASSINIT_PROBE_WAIT(erroneous, this_k, -1,wait);
 740       ResourceMark rm(THREAD);
 741       const char* desc = "Could not initialize class ";
 742       const char* className = this_k->external_name();
 743       size_t msglen = strlen(desc) + strlen(className) + 1;
 744       char* message = NEW_RESOURCE_ARRAY(char, msglen);
 745       if (NULL == message) {
 746         // Out of memory: can't create detailed error message
 747         THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), className);
 748       } else {
 749         jio_snprintf(message, msglen, "%s%s", desc, className);
 750         THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), message);
 751       }
 752     }
 753 
 754     // Step 6
 755     this_k->set_init_state(being_initialized);
 756     this_k->set_init_thread(self);
 757   }
 758 
 759   // Step 7
 760   // Next, if C is a class rather than an interface, initialize it's super class and super
 761   // interfaces.
 762   if (!this_k->is_interface()) {
 763     Klass* super_klass = this_k->super();
 764     if (super_klass != NULL && super_klass->should_be_initialized()) {
 765       super_klass->initialize(THREAD);
 766     }
 767     // If C implements any interface that declares a non-static, concrete method,
 768     // the initialization of C triggers initialization of its super interfaces.
 769     // Only need to recurse if has_nonstatic_concrete_methods which includes declaring and
 770     // having a superinterface that declares, non-static, concrete methods
 771     if (!HAS_PENDING_EXCEPTION && this_k->has_nonstatic_concrete_methods()) {
 772       this_k->initialize_super_interfaces(this_k, THREAD);
 773     }
 774 
 775     // If any exceptions, complete abruptly, throwing the same exception as above.
 776     if (HAS_PENDING_EXCEPTION) {
 777       Handle e(THREAD, PENDING_EXCEPTION);
 778       CLEAR_PENDING_EXCEPTION;
 779       {
 780         EXCEPTION_MARK;
 781         // Locks object, set state, and notify all waiting threads
 782         this_k->set_initialization_state_and_notify(initialization_error, THREAD);
 783         CLEAR_PENDING_EXCEPTION;
 784       }
 785       DTRACE_CLASSINIT_PROBE_WAIT(super__failed, this_k, -1,wait);
 786       THROW_OOP(e());
 787     }
 788   }
 789 
 790 
 791   // Look for aot compiled methods for this klass, including class initializer.
 792   AOTLoader::load_for_klass(this_k, THREAD);
 793 
 794   // Step 8
 795   {
 796     assert(THREAD->is_Java_thread(), "non-JavaThread in initialize_impl");
 797     JavaThread* jt = (JavaThread*)THREAD;
 798     DTRACE_CLASSINIT_PROBE_WAIT(clinit, this_k, -1,wait);
 799     // Timer includes any side effects of class initialization (resolution,
 800     // etc), but not recursive entry into call_class_initializer().
 801     PerfClassTraceTime timer(ClassLoader::perf_class_init_time(),
 802                              ClassLoader::perf_class_init_selftime(),
 803                              ClassLoader::perf_classes_inited(),
 804                              jt->get_thread_stat()->perf_recursion_counts_addr(),
 805                              jt->get_thread_stat()->perf_timers_addr(),
 806                              PerfClassTraceTime::CLASS_CLINIT);
 807     this_k->call_class_initializer(THREAD);
 808   }
 809 
 810   // Step 9
 811   if (!HAS_PENDING_EXCEPTION) {
 812     this_k->set_initialization_state_and_notify(fully_initialized, CHECK);
 813     { ResourceMark rm(THREAD);
 814       debug_only(this_k->vtable()->verify(tty, true);)
 815     }
 816   }
 817   else {
 818     // Step 10 and 11
 819     Handle e(THREAD, PENDING_EXCEPTION);
 820     CLEAR_PENDING_EXCEPTION;
 821     // JVMTI has already reported the pending exception
 822     // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
 823     JvmtiExport::clear_detected_exception((JavaThread*)THREAD);
 824     {
 825       EXCEPTION_MARK;
 826       this_k->set_initialization_state_and_notify(initialization_error, THREAD);
 827       CLEAR_PENDING_EXCEPTION;   // ignore any exception thrown, class initialization error is thrown below
 828       // JVMTI has already reported the pending exception
 829       // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
 830       JvmtiExport::clear_detected_exception((JavaThread*)THREAD);
 831     }
 832     DTRACE_CLASSINIT_PROBE_WAIT(error, this_k, -1,wait);
 833     if (e->is_a(SystemDictionary::Error_klass())) {
 834       THROW_OOP(e());
 835     } else {
 836       JavaCallArguments args(e);
 837       THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(),
 838                 vmSymbols::throwable_void_signature(),
 839                 &args);
 840     }
 841   }
 842   DTRACE_CLASSINIT_PROBE_WAIT(end, this_k, -1,wait);
 843 }
 844 
 845 
 846 // Note: implementation moved to static method to expose the this pointer.
 847 void InstanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) {
 848   set_initialization_state_and_notify_impl(this, state, CHECK);

 849 }
 850 
 851 void InstanceKlass::set_initialization_state_and_notify_impl(InstanceKlass* this_k, ClassState state, TRAPS) {
 852   Handle init_lock(THREAD, this_k->init_lock());
 853   if (init_lock() != NULL) {
 854     ObjectLocker ol(init_lock, THREAD);
 855     this_k->set_init_state(state);
 856     this_k->fence_and_clear_init_lock();
 857     ol.notify_all(CHECK);
 858   } else {
 859     assert(init_lock() != NULL, "The initialization state should never be set twice");
 860     this_k->set_init_state(state);
 861   }
 862 }
 863 
 864 // The embedded _implementor field can only record one implementor.
 865 // When there are more than one implementors, the _implementor field
 866 // is set to the interface Klass* itself. Following are the possible
 867 // values for the _implementor field:
 868 //   NULL                  - no implementor
 869 //   implementor Klass*    - one implementor
 870 //   self                  - more than one implementor
 871 //
 872 // The _implementor field only exists for interfaces.
 873 void InstanceKlass::add_implementor(Klass* k) {
 874   assert(Compile_lock->owned_by_self(), "");
 875   assert(is_interface(), "not interface");
 876   // Filter out my subinterfaces.
 877   // (Note: Interfaces are never on the subklass list.)
 878   if (InstanceKlass::cast(k)->is_interface()) return;
 879 
 880   // Filter out subclasses whose supers already implement me.
 881   // (Note: CHA must walk subclasses of direct implementors
 882   // in order to locate indirect implementors.)
 883   Klass* sk = k->super();
 884   if (sk != NULL && InstanceKlass::cast(sk)->implements_interface(this))
 885     // We only need to check one immediate superclass, since the
 886     // implements_interface query looks at transitive_interfaces.
 887     // Any supers of the super have the same (or fewer) transitive_interfaces.
 888     return;
 889 
 890   Klass* ik = implementor();
 891   if (ik == NULL) {
 892     set_implementor(k);
 893   } else if (ik != this) {
 894     // There is already an implementor. Use itself as an indicator of
 895     // more than one implementors.
 896     set_implementor(this);
 897   }
 898 
 899   // The implementor also implements the transitive_interfaces
 900   for (int index = 0; index < local_interfaces()->length(); index++) {
 901     InstanceKlass::cast(local_interfaces()->at(index))->add_implementor(k);
 902   }
 903 }
 904 
 905 void InstanceKlass::init_implementor() {
 906   if (is_interface()) {
 907     set_implementor(NULL);
 908   }
 909 }
 910 
 911 
 912 void InstanceKlass::process_interfaces(Thread *thread) {
 913   // link this class into the implementors list of every interface it implements
 914   for (int i = local_interfaces()->length() - 1; i >= 0; i--) {
 915     assert(local_interfaces()->at(i)->is_klass(), "must be a klass");
 916     InstanceKlass* interf = InstanceKlass::cast(local_interfaces()->at(i));
 917     assert(interf->is_interface(), "expected interface");
 918     interf->add_implementor(this);
 919   }
 920 }
 921 
 922 bool InstanceKlass::can_be_primary_super_slow() const {
 923   if (is_interface())
 924     return false;
 925   else
 926     return Klass::can_be_primary_super_slow();
 927 }
 928 
 929 GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots) {
 930   // The secondaries are the implemented interfaces.
 931   Array<Klass*>* interfaces = transitive_interfaces();
 932   int num_secondaries = num_extra_slots + interfaces->length();
 933   if (num_secondaries == 0) {
 934     // Must share this for correct bootstrapping!
 935     set_secondary_supers(Universe::the_empty_klass_array());
 936     return NULL;
 937   } else if (num_extra_slots == 0) {
 938     // The secondary super list is exactly the same as the transitive interfaces.
 939     // Redefine classes has to be careful not to delete this!
 940     set_secondary_supers(interfaces);
 941     return NULL;
 942   } else {
 943     // Copy transitive interfaces to a temporary growable array to be constructed
 944     // into the secondary super list with extra slots.
 945     GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length());
 946     for (int i = 0; i < interfaces->length(); i++) {
 947       secondaries->push(interfaces->at(i));
 948     }
 949     return secondaries;
 950   }
 951 }
 952 
 953 bool InstanceKlass::compute_is_subtype_of(Klass* k) {
 954   if (k->is_interface()) {
 955     return implements_interface(k);
 956   } else {
 957     return Klass::compute_is_subtype_of(k);
 958   }
 959 }
 960 
 961 bool InstanceKlass::implements_interface(Klass* k) const {
 962   if (this == k) return true;
 963   assert(k->is_interface(), "should be an interface class");
 964   for (int i = 0; i < transitive_interfaces()->length(); i++) {
 965     if (transitive_interfaces()->at(i) == k) {
 966       return true;
 967     }
 968   }
 969   return false;
 970 }
 971 
 972 bool InstanceKlass::is_same_or_direct_interface(Klass *k) const {
 973   // Verify direct super interface
 974   if (this == k) return true;
 975   assert(k->is_interface(), "should be an interface class");
 976   for (int i = 0; i < local_interfaces()->length(); i++) {
 977     if (local_interfaces()->at(i) == k) {
 978       return true;
 979     }
 980   }
 981   return false;
 982 }
 983 
 984 objArrayOop InstanceKlass::allocate_objArray(int n, int length, TRAPS) {
 985   if (length < 0) THROW_0(vmSymbols::java_lang_NegativeArraySizeException());
 986   if (length > arrayOopDesc::max_array_length(T_OBJECT)) {
 987     report_java_out_of_memory("Requested array size exceeds VM limit");
 988     JvmtiExport::post_array_size_exhausted();
 989     THROW_OOP_0(Universe::out_of_memory_error_array_size());
 990   }
 991   int size = objArrayOopDesc::object_size(length);
 992   Klass* ak = array_klass(n, CHECK_NULL);

 993   objArrayOop o =
 994     (objArrayOop)CollectedHeap::array_allocate(ak, size, length, CHECK_NULL);
 995   return o;
 996 }
 997 
 998 instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) {
 999   if (TraceFinalizerRegistration) {
1000     tty->print("Registered ");
1001     i->print_value_on(tty);
1002     tty->print_cr(" (" INTPTR_FORMAT ") as finalizable", p2i(i));
1003   }
1004   instanceHandle h_i(THREAD, i);
1005   // Pass the handle as argument, JavaCalls::call expects oop as jobjects
1006   JavaValue result(T_VOID);
1007   JavaCallArguments args(h_i);
1008   methodHandle mh (THREAD, Universe::finalizer_register_method());
1009   JavaCalls::call(&result, mh, &args, CHECK_NULL);
1010   return h_i();
1011 }
1012 
1013 instanceOop InstanceKlass::allocate_instance(TRAPS) {
1014   bool has_finalizer_flag = has_finalizer(); // Query before possible GC
1015   int size = size_helper();  // Query before forming handle.
1016 


1017   instanceOop i;
1018 
1019   i = (instanceOop)CollectedHeap::obj_allocate(this, size, CHECK_NULL);
1020   if (has_finalizer_flag && !RegisterFinalizersAtInit) {
1021     i = register_finalizer(i, CHECK_NULL);
1022   }
1023   return i;
1024 }
1025 
1026 void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) {
1027   if (is_interface() || is_abstract()) {
1028     ResourceMark rm(THREAD);
1029     THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
1030               : vmSymbols::java_lang_InstantiationException(), external_name());
1031   }
1032   if (this == SystemDictionary::Class_klass()) {
1033     ResourceMark rm(THREAD);
1034     THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError()
1035               : vmSymbols::java_lang_IllegalAccessException(), external_name());
1036   }
1037 }
1038 
1039 Klass* InstanceKlass::array_klass_impl(bool or_null, int n, TRAPS) {
1040   return array_klass_impl(this, or_null, n, THREAD);

1041 }
1042 
1043 Klass* InstanceKlass::array_klass_impl(InstanceKlass* this_k, bool or_null, int n, TRAPS) {
1044   // Need load-acquire for lock-free read
1045   if (this_k->array_klasses_acquire() == NULL) {
1046     if (or_null) return NULL;
1047 
1048     ResourceMark rm;
1049     JavaThread *jt = (JavaThread *)THREAD;
1050     {
1051       // Atomic creation of array_klasses
1052       MutexLocker mc(Compile_lock, THREAD);   // for vtables
1053       MutexLocker ma(MultiArray_lock, THREAD);
1054 
1055       // Check if update has already taken place
1056       if (this_k->array_klasses() == NULL) {
1057         Klass*    k = ObjArrayKlass::allocate_objArray_klass(this_k->class_loader_data(), 1, this_k, CHECK_NULL);
1058         // use 'release' to pair with lock-free load
1059         this_k->release_set_array_klasses(k);
1060       }
1061     }
1062   }
1063   // _this will always be set at this point
1064   ObjArrayKlass* oak = (ObjArrayKlass*)this_k->array_klasses();
1065   if (or_null) {
1066     return oak->array_klass_or_null(n);
1067   }
1068   return oak->array_klass(n, THREAD);
1069 }
1070 
1071 Klass* InstanceKlass::array_klass_impl(bool or_null, TRAPS) {
1072   return array_klass_impl(or_null, 1, THREAD);
1073 }
1074 
1075 void InstanceKlass::call_class_initializer(TRAPS) {
1076   call_class_initializer_impl(this, THREAD);

1077 }
1078 
1079 static int call_class_initializer_impl_counter = 0;   // for debugging
1080 
1081 Method* InstanceKlass::class_initializer() const {
1082   Method* clinit = find_method(
1083       vmSymbols::class_initializer_name(), vmSymbols::void_method_signature());
1084   if (clinit != NULL && clinit->has_valid_initializer_flags()) {
1085     return clinit;
1086   }
1087   return NULL;
1088 }
1089 
1090 void InstanceKlass::call_class_initializer_impl(InstanceKlass* this_k, TRAPS) {
1091   if (ReplayCompiles &&
1092       (ReplaySuppressInitializers == 1 ||
1093        ReplaySuppressInitializers >= 2 && this_k->class_loader() != NULL)) {
1094     // Hide the existence of the initializer for the purpose of replaying the compile
1095     return;
1096   }
1097 
1098   methodHandle h_method(THREAD, this_k->class_initializer());
1099   assert(!this_k->is_initialized(), "we cannot initialize twice");
1100   if (log_is_enabled(Info, class, init)) {
1101     ResourceMark rm;
1102     outputStream* log = Log(class, init)::info_stream();
1103     log->print("%d Initializing ", call_class_initializer_impl_counter++);
1104     this_k->name()->print_value_on(log);
1105     log->print_cr("%s (" INTPTR_FORMAT ")", h_method() == NULL ? "(no method)" : "", p2i(this_k));
1106   }
1107   if (h_method() != NULL) {
1108     JavaCallArguments args; // No arguments
1109     JavaValue result(T_VOID);
1110     JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args)
1111   }
1112 }
1113 
1114 
1115 void InstanceKlass::mask_for(const methodHandle& method, int bci,
1116   InterpreterOopMap* entry_for) {
1117   // Lazily create the _oop_map_cache at first request
1118   // Lock-free access requires load_ptr_acquire.
1119   OopMapCache* oop_map_cache =
1120       static_cast<OopMapCache*>(OrderAccess::load_ptr_acquire(&_oop_map_cache));
1121   if (oop_map_cache == NULL) {
1122     MutexLocker x(OopMapCacheAlloc_lock);
1123     // Check if _oop_map_cache was allocated while we were waiting for this lock
1124     if ((oop_map_cache = _oop_map_cache) == NULL) {
1125       oop_map_cache = new OopMapCache();
1126       // Ensure _oop_map_cache is stable, since it is examined without a lock
1127       OrderAccess::release_store_ptr(&_oop_map_cache, oop_map_cache);
1128     }
1129   }
1130   // _oop_map_cache is constant after init; lookup below does its own locking.
1131   oop_map_cache->lookup(method, bci, entry_for);
1132 }
1133 
1134 
1135 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1136   for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1137     Symbol* f_name = fs.name();
1138     Symbol* f_sig  = fs.signature();
1139     if (f_name == name && f_sig == sig) {
1140       fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1141       return true;
1142     }
1143   }
1144   return false;
1145 }
1146 
1147 
1148 Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1149   const int n = local_interfaces()->length();
1150   for (int i = 0; i < n; i++) {
1151     Klass* intf1 = local_interfaces()->at(i);
1152     assert(intf1->is_interface(), "just checking type");
1153     // search for field in current interface
1154     if (InstanceKlass::cast(intf1)->find_local_field(name, sig, fd)) {
1155       assert(fd->is_static(), "interface field must be static");
1156       return intf1;
1157     }
1158     // search for field in direct superinterfaces
1159     Klass* intf2 = InstanceKlass::cast(intf1)->find_interface_field(name, sig, fd);
1160     if (intf2 != NULL) return intf2;
1161   }
1162   // otherwise field lookup fails
1163   return NULL;
1164 }
1165 
1166 
1167 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1168   // search order according to newest JVM spec (5.4.3.2, p.167).
1169   // 1) search for field in current klass
1170   if (find_local_field(name, sig, fd)) {
1171     return const_cast<InstanceKlass*>(this);
1172   }
1173   // 2) search for field recursively in direct superinterfaces
1174   { Klass* intf = find_interface_field(name, sig, fd);
1175     if (intf != NULL) return intf;
1176   }
1177   // 3) apply field lookup recursively if superclass exists
1178   { Klass* supr = super();
1179     if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, fd);
1180   }
1181   // 4) otherwise field lookup fails
1182   return NULL;
1183 }
1184 
1185 
1186 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const {
1187   // search order according to newest JVM spec (5.4.3.2, p.167).
1188   // 1) search for field in current klass
1189   if (find_local_field(name, sig, fd)) {
1190     if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this);
1191   }
1192   // 2) search for field recursively in direct superinterfaces
1193   if (is_static) {
1194     Klass* intf = find_interface_field(name, sig, fd);
1195     if (intf != NULL) return intf;
1196   }
1197   // 3) apply field lookup recursively if superclass exists
1198   { Klass* supr = super();
1199     if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, is_static, fd);
1200   }
1201   // 4) otherwise field lookup fails
1202   return NULL;
1203 }
1204 
1205 
1206 bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1207   for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1208     if (fs.offset() == offset) {
1209       fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1210       if (fd->is_static() == is_static) return true;
1211     }
1212   }
1213   return false;
1214 }
1215 
1216 
1217 bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1218   Klass* klass = const_cast<InstanceKlass*>(this);
1219   while (klass != NULL) {
1220     if (InstanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) {
1221       return true;
1222     }
1223     klass = klass->super();
1224   }
1225   return false;
1226 }
1227 
1228 
1229 void InstanceKlass::methods_do(void f(Method* method)) {
1230   // Methods aren't stable until they are loaded.  This can be read outside
1231   // a lock through the ClassLoaderData for profiling
1232   if (!is_loaded()) {
1233     return;
1234   }
1235 
1236   int len = methods()->length();
1237   for (int index = 0; index < len; index++) {
1238     Method* m = methods()->at(index);
1239     assert(m->is_method(), "must be method");
1240     f(m);
1241   }
1242 }
1243 
1244 
1245 void InstanceKlass::do_local_static_fields(FieldClosure* cl) {
1246   for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1247     if (fs.access_flags().is_static()) {
1248       fieldDescriptor& fd = fs.field_descriptor();
1249       cl->do_field(&fd);
1250     }
1251   }
1252 }
1253 
1254 
1255 void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle mirror, TRAPS) {
1256   do_local_static_fields_impl(this, f, mirror, CHECK);

1257 }
1258 
1259 
1260 void InstanceKlass::do_local_static_fields_impl(InstanceKlass* this_k,
1261                              void f(fieldDescriptor* fd, Handle, TRAPS), Handle mirror, TRAPS) {
1262   for (JavaFieldStream fs(this_k); !fs.done(); fs.next()) {
1263     if (fs.access_flags().is_static()) {
1264       fieldDescriptor& fd = fs.field_descriptor();
1265       f(&fd, mirror, CHECK);
1266     }
1267   }
1268 }
1269 
1270 
1271 static int compare_fields_by_offset(int* a, int* b) {
1272   return a[0] - b[0];
1273 }
1274 
1275 void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) {
1276   InstanceKlass* super = superklass();
1277   if (super != NULL) {
1278     super->do_nonstatic_fields(cl);
1279   }
1280   fieldDescriptor fd;
1281   int length = java_fields_count();
1282   // In DebugInfo nonstatic fields are sorted by offset.
1283   int* fields_sorted = NEW_C_HEAP_ARRAY(int, 2*(length+1), mtClass);
1284   int j = 0;
1285   for (int i = 0; i < length; i += 1) {
1286     fd.reinitialize(this, i);
1287     if (!fd.is_static()) {
1288       fields_sorted[j + 0] = fd.offset();
1289       fields_sorted[j + 1] = i;
1290       j += 2;
1291     }
1292   }
1293   if (j > 0) {
1294     length = j;
1295     // _sort_Fn is defined in growableArray.hpp.
1296     qsort(fields_sorted, length/2, 2*sizeof(int), (_sort_Fn)compare_fields_by_offset);
1297     for (int i = 0; i < length; i += 2) {
1298       fd.reinitialize(this, fields_sorted[i + 1]);
1299       assert(!fd.is_static() && fd.offset() == fields_sorted[i], "only nonstatic fields");
1300       cl->do_field(&fd);
1301     }
1302   }
1303   FREE_C_HEAP_ARRAY(int, fields_sorted);
1304 }
1305 
1306 
1307 void InstanceKlass::array_klasses_do(void f(Klass* k, TRAPS), TRAPS) {
1308   if (array_klasses() != NULL)
1309     ArrayKlass::cast(array_klasses())->array_klasses_do(f, THREAD);
1310 }
1311 
1312 void InstanceKlass::array_klasses_do(void f(Klass* k)) {
1313   if (array_klasses() != NULL)
1314     ArrayKlass::cast(array_klasses())->array_klasses_do(f);
1315 }
1316 
1317 #ifdef ASSERT
1318 static int linear_search(const Array<Method*>* methods,
1319                          const Symbol* name,
1320                          const Symbol* signature) {
1321   const int len = methods->length();
1322   for (int index = 0; index < len; index++) {
1323     const Method* const m = methods->at(index);
1324     assert(m->is_method(), "must be method");
1325     if (m->signature() == signature && m->name() == name) {
1326        return index;
1327     }
1328   }
1329   return -1;
1330 }
1331 #endif
1332 
1333 static int binary_search(const Array<Method*>* methods, const Symbol* name) {
1334   int len = methods->length();
1335   // methods are sorted, so do binary search
1336   int l = 0;
1337   int h = len - 1;
1338   while (l <= h) {
1339     int mid = (l + h) >> 1;
1340     Method* m = methods->at(mid);
1341     assert(m->is_method(), "must be method");
1342     int res = m->name()->fast_compare(name);
1343     if (res == 0) {
1344       return mid;
1345     } else if (res < 0) {
1346       l = mid + 1;
1347     } else {
1348       h = mid - 1;
1349     }
1350   }
1351   return -1;
1352 }
1353 
1354 // find_method looks up the name/signature in the local methods array
1355 Method* InstanceKlass::find_method(const Symbol* name,
1356                                    const Symbol* signature) const {
1357   return find_method_impl(name, signature, find_overpass, find_static, find_private);
1358 }
1359 
1360 Method* InstanceKlass::find_method_impl(const Symbol* name,
1361                                         const Symbol* signature,
1362                                         OverpassLookupMode overpass_mode,
1363                                         StaticLookupMode static_mode,
1364                                         PrivateLookupMode private_mode) const {
1365   return InstanceKlass::find_method_impl(methods(),
1366                                          name,
1367                                          signature,
1368                                          overpass_mode,
1369                                          static_mode,
1370                                          private_mode);
1371 }
1372 
1373 // find_instance_method looks up the name/signature in the local methods array
1374 // and skips over static methods
1375 Method* InstanceKlass::find_instance_method(const Array<Method*>* methods,
1376                                             const Symbol* name,
1377                                             const Symbol* signature) {
1378   Method* const meth = InstanceKlass::find_method_impl(methods,
1379                                                  name,
1380                                                  signature,
1381                                                  find_overpass,
1382                                                  skip_static,
1383                                                  find_private);
1384   assert(((meth == NULL) || !meth->is_static()),
1385     "find_instance_method should have skipped statics");
1386   return meth;
1387 }
1388 
1389 // find_instance_method looks up the name/signature in the local methods array
1390 // and skips over static methods
1391 Method* InstanceKlass::find_instance_method(const Symbol* name, const Symbol* signature) const {
1392   return InstanceKlass::find_instance_method(methods(), name, signature);
1393 }
1394 
1395 // Find looks up the name/signature in the local methods array
1396 // and filters on the overpass, static and private flags
1397 // This returns the first one found
1398 // note that the local methods array can have up to one overpass, one static
1399 // and one instance (private or not) with the same name/signature
1400 Method* InstanceKlass::find_local_method(const Symbol* name,
1401                                          const Symbol* signature,
1402                                          OverpassLookupMode overpass_mode,
1403                                          StaticLookupMode static_mode,
1404                                          PrivateLookupMode private_mode) const {
1405   return InstanceKlass::find_method_impl(methods(),
1406                                          name,
1407                                          signature,
1408                                          overpass_mode,
1409                                          static_mode,
1410                                          private_mode);
1411 }
1412 
1413 // Find looks up the name/signature in the local methods array
1414 // and filters on the overpass, static and private flags
1415 // This returns the first one found
1416 // note that the local methods array can have up to one overpass, one static
1417 // and one instance (private or not) with the same name/signature
1418 Method* InstanceKlass::find_local_method(const Array<Method*>* methods,
1419                                          const Symbol* name,
1420                                          const Symbol* signature,
1421                                          OverpassLookupMode overpass_mode,
1422                                          StaticLookupMode static_mode,
1423                                          PrivateLookupMode private_mode) {
1424   return InstanceKlass::find_method_impl(methods,
1425                                          name,
1426                                          signature,
1427                                          overpass_mode,
1428                                          static_mode,
1429                                          private_mode);
1430 }
1431 
1432 Method* InstanceKlass::find_method(const Array<Method*>* methods,
1433                                    const Symbol* name,
1434                                    const Symbol* signature) {
1435   return InstanceKlass::find_method_impl(methods,
1436                                          name,
1437                                          signature,
1438                                          find_overpass,
1439                                          find_static,
1440                                          find_private);
1441 }
1442 
1443 Method* InstanceKlass::find_method_impl(const Array<Method*>* methods,
1444                                         const Symbol* name,
1445                                         const Symbol* signature,
1446                                         OverpassLookupMode overpass_mode,
1447                                         StaticLookupMode static_mode,
1448                                         PrivateLookupMode private_mode) {
1449   int hit = find_method_index(methods, name, signature, overpass_mode, static_mode, private_mode);
1450   return hit >= 0 ? methods->at(hit): NULL;
1451 }
1452 
1453 // true if method matches signature and conforms to skipping_X conditions.
1454 static bool method_matches(const Method* m,
1455                            const Symbol* signature,
1456                            bool skipping_overpass,
1457                            bool skipping_static,
1458                            bool skipping_private) {
1459   return ((m->signature() == signature) &&
1460     (!skipping_overpass || !m->is_overpass()) &&
1461     (!skipping_static || !m->is_static()) &&
1462     (!skipping_private || !m->is_private()));
1463 }
1464 
1465 // Used directly for default_methods to find the index into the
1466 // default_vtable_indices, and indirectly by find_method
1467 // find_method_index looks in the local methods array to return the index
1468 // of the matching name/signature. If, overpass methods are being ignored,
1469 // the search continues to find a potential non-overpass match.  This capability
1470 // is important during method resolution to prefer a static method, for example,
1471 // over an overpass method.
1472 // There is the possibility in any _method's array to have the same name/signature
1473 // for a static method, an overpass method and a local instance method
1474 // To correctly catch a given method, the search criteria may need
1475 // to explicitly skip the other two. For local instance methods, it
1476 // is often necessary to skip private methods
1477 int InstanceKlass::find_method_index(const Array<Method*>* methods,
1478                                      const Symbol* name,
1479                                      const Symbol* signature,
1480                                      OverpassLookupMode overpass_mode,
1481                                      StaticLookupMode static_mode,
1482                                      PrivateLookupMode private_mode) {
1483   const bool skipping_overpass = (overpass_mode == skip_overpass);
1484   const bool skipping_static = (static_mode == skip_static);
1485   const bool skipping_private = (private_mode == skip_private);
1486   const int hit = binary_search(methods, name);
1487   if (hit != -1) {
1488     const Method* const m = methods->at(hit);
1489 
1490     // Do linear search to find matching signature.  First, quick check
1491     // for common case, ignoring overpasses if requested.
1492     if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1493           return hit;
1494     }
1495 
1496     // search downwards through overloaded methods
1497     int i;
1498     for (i = hit - 1; i >= 0; --i) {
1499         const Method* const m = methods->at(i);
1500         assert(m->is_method(), "must be method");
1501         if (m->name() != name) {
1502           break;
1503         }
1504         if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1505           return i;
1506         }
1507     }
1508     // search upwards
1509     for (i = hit + 1; i < methods->length(); ++i) {
1510         const Method* const m = methods->at(i);
1511         assert(m->is_method(), "must be method");
1512         if (m->name() != name) {
1513           break;
1514         }
1515         if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1516           return i;
1517         }
1518     }
1519     // not found
1520 #ifdef ASSERT
1521     const int index = (skipping_overpass || skipping_static || skipping_private) ? -1 :
1522       linear_search(methods, name, signature);
1523     assert(-1 == index, "binary search should have found entry %d", index);
1524 #endif
1525   }
1526   return -1;
1527 }
1528 
1529 int InstanceKlass::find_method_by_name(const Symbol* name, int* end) const {
1530   return find_method_by_name(methods(), name, end);
1531 }
1532 
1533 int InstanceKlass::find_method_by_name(const Array<Method*>* methods,
1534                                        const Symbol* name,
1535                                        int* end_ptr) {
1536   assert(end_ptr != NULL, "just checking");
1537   int start = binary_search(methods, name);
1538   int end = start + 1;
1539   if (start != -1) {
1540     while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start;
1541     while (end < methods->length() && (methods->at(end))->name() == name) ++end;
1542     *end_ptr = end;
1543     return start;
1544   }
1545   return -1;
1546 }
1547 
1548 // uncached_lookup_method searches both the local class methods array and all
1549 // superclasses methods arrays, skipping any overpass methods in superclasses.
1550 Method* InstanceKlass::uncached_lookup_method(const Symbol* name,
1551                                               const Symbol* signature,
1552                                               OverpassLookupMode overpass_mode) const {
1553   OverpassLookupMode overpass_local_mode = overpass_mode;
1554   const Klass* klass = this;
1555   while (klass != NULL) {
1556     Method* const method = InstanceKlass::cast(klass)->find_method_impl(name,
1557                                                                         signature,
1558                                                                         overpass_local_mode,
1559                                                                         find_static,
1560                                                                         find_private);
1561     if (method != NULL) {
1562       return method;
1563     }
1564     klass = klass->super();
1565     overpass_local_mode = skip_overpass;   // Always ignore overpass methods in superclasses
1566   }
1567   return NULL;
1568 }
1569 
1570 #ifdef ASSERT
1571 // search through class hierarchy and return true if this class or
1572 // one of the superclasses was redefined
1573 bool InstanceKlass::has_redefined_this_or_super() const {
1574   const Klass* klass = this;
1575   while (klass != NULL) {
1576     if (InstanceKlass::cast(klass)->has_been_redefined()) {
1577       return true;
1578     }
1579     klass = klass->super();
1580   }
1581   return false;
1582 }
1583 #endif
1584 
1585 // lookup a method in the default methods list then in all transitive interfaces
1586 // Do NOT return private or static methods
1587 Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name,
1588                                                          Symbol* signature) const {
1589   Method* m = NULL;
1590   if (default_methods() != NULL) {
1591     m = find_method(default_methods(), name, signature);
1592   }
1593   // Look up interfaces
1594   if (m == NULL) {
1595     m = lookup_method_in_all_interfaces(name, signature, find_defaults);
1596   }
1597   return m;
1598 }
1599 
1600 // lookup a method in all the interfaces that this class implements
1601 // Do NOT return private or static methods, new in JDK8 which are not externally visible
1602 // They should only be found in the initial InterfaceMethodRef
1603 Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name,
1604                                                        Symbol* signature,
1605                                                        DefaultsLookupMode defaults_mode) const {
1606   Array<Klass*>* all_ifs = transitive_interfaces();
1607   int num_ifs = all_ifs->length();
1608   InstanceKlass *ik = NULL;
1609   for (int i = 0; i < num_ifs; i++) {
1610     ik = InstanceKlass::cast(all_ifs->at(i));
1611     Method* m = ik->lookup_method(name, signature);
1612     if (m != NULL && m->is_public() && !m->is_static() &&
1613         ((defaults_mode != skip_defaults) || !m->is_default_method())) {
1614       return m;
1615     }
1616   }
1617   return NULL;
1618 }
1619 
1620 /* jni_id_for_impl for jfieldIds only */
1621 JNIid* InstanceKlass::jni_id_for_impl(InstanceKlass* this_k, int offset) {
1622   MutexLocker ml(JfieldIdCreation_lock);
1623   // Retry lookup after we got the lock
1624   JNIid* probe = this_k->jni_ids() == NULL ? NULL : this_k->jni_ids()->find(offset);
1625   if (probe == NULL) {
1626     // Slow case, allocate new static field identifier
1627     probe = new JNIid(this_k, offset, this_k->jni_ids());
1628     this_k->set_jni_ids(probe);
1629   }
1630   return probe;
1631 }
1632 
1633 
1634 /* jni_id_for for jfieldIds only */
1635 JNIid* InstanceKlass::jni_id_for(int offset) {
1636   JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset);
1637   if (probe == NULL) {
1638     probe = jni_id_for_impl(this, offset);
1639   }
1640   return probe;
1641 }
1642 
1643 u2 InstanceKlass::enclosing_method_data(int offset) const {
1644   const Array<jushort>* const inner_class_list = inner_classes();
1645   if (inner_class_list == NULL) {
1646     return 0;
1647   }
1648   const int length = inner_class_list->length();
1649   if (length % inner_class_next_offset == 0) {
1650     return 0;
1651   }
1652   const int index = length - enclosing_method_attribute_size;
1653   assert(offset < enclosing_method_attribute_size, "invalid offset");
1654   return inner_class_list->at(index + offset);
1655 }
1656 
1657 void InstanceKlass::set_enclosing_method_indices(u2 class_index,
1658                                                  u2 method_index) {
1659   Array<jushort>* inner_class_list = inner_classes();
1660   assert (inner_class_list != NULL, "_inner_classes list is not set up");
1661   int length = inner_class_list->length();
1662   if (length % inner_class_next_offset == enclosing_method_attribute_size) {
1663     int index = length - enclosing_method_attribute_size;
1664     inner_class_list->at_put(
1665       index + enclosing_method_class_index_offset, class_index);
1666     inner_class_list->at_put(
1667       index + enclosing_method_method_index_offset, method_index);
1668   }
1669 }
1670 
1671 // Lookup or create a jmethodID.
1672 // This code is called by the VMThread and JavaThreads so the
1673 // locking has to be done very carefully to avoid deadlocks
1674 // and/or other cache consistency problems.
1675 //
1676 jmethodID InstanceKlass::get_jmethod_id(InstanceKlass* ik, const methodHandle& method_h) {
1677   size_t idnum = (size_t)method_h->method_idnum();
1678   jmethodID* jmeths = ik->methods_jmethod_ids_acquire();
1679   size_t length = 0;
1680   jmethodID id = NULL;
1681 
1682   // We use a double-check locking idiom here because this cache is
1683   // performance sensitive. In the normal system, this cache only
1684   // transitions from NULL to non-NULL which is safe because we use
1685   // release_set_methods_jmethod_ids() to advertise the new cache.
1686   // A partially constructed cache should never be seen by a racing
1687   // thread. We also use release_store_ptr() to save a new jmethodID
1688   // in the cache so a partially constructed jmethodID should never be
1689   // seen either. Cache reads of existing jmethodIDs proceed without a
1690   // lock, but cache writes of a new jmethodID requires uniqueness and
1691   // creation of the cache itself requires no leaks so a lock is
1692   // generally acquired in those two cases.
1693   //
1694   // If the RedefineClasses() API has been used, then this cache can
1695   // grow and we'll have transitions from non-NULL to bigger non-NULL.
1696   // Cache creation requires no leaks and we require safety between all
1697   // cache accesses and freeing of the old cache so a lock is generally
1698   // acquired when the RedefineClasses() API has been used.
1699 
1700   if (jmeths != NULL) {
1701     // the cache already exists
1702     if (!ik->idnum_can_increment()) {
1703       // the cache can't grow so we can just get the current values
1704       get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1705     } else {
1706       // cache can grow so we have to be more careful
1707       if (Threads::number_of_threads() == 0 ||
1708           SafepointSynchronize::is_at_safepoint()) {
1709         // we're single threaded or at a safepoint - no locking needed
1710         get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1711       } else {
1712         MutexLocker ml(JmethodIdCreation_lock);
1713         get_jmethod_id_length_value(jmeths, idnum, &length, &id);
1714       }
1715     }
1716   }
1717   // implied else:
1718   // we need to allocate a cache so default length and id values are good
1719 
1720   if (jmeths == NULL ||   // no cache yet
1721       length <= idnum ||  // cache is too short
1722       id == NULL) {       // cache doesn't contain entry
1723 
1724     // This function can be called by the VMThread so we have to do all
1725     // things that might block on a safepoint before grabbing the lock.
1726     // Otherwise, we can deadlock with the VMThread or have a cache
1727     // consistency issue. These vars keep track of what we might have
1728     // to free after the lock is dropped.
1729     jmethodID  to_dealloc_id     = NULL;
1730     jmethodID* to_dealloc_jmeths = NULL;
1731 
1732     // may not allocate new_jmeths or use it if we allocate it
1733     jmethodID* new_jmeths = NULL;
1734     if (length <= idnum) {
1735       // allocate a new cache that might be used
1736       size_t size = MAX2(idnum+1, (size_t)ik->idnum_allocated_count());
1737       new_jmeths = NEW_C_HEAP_ARRAY(jmethodID, size+1, mtClass);
1738       memset(new_jmeths, 0, (size+1)*sizeof(jmethodID));
1739       // cache size is stored in element[0], other elements offset by one
1740       new_jmeths[0] = (jmethodID)size;
1741     }
1742 
1743     // allocate a new jmethodID that might be used
1744     jmethodID new_id = NULL;
1745     if (method_h->is_old() && !method_h->is_obsolete()) {
1746       // The method passed in is old (but not obsolete), we need to use the current version
1747       Method* current_method = ik->method_with_idnum((int)idnum);
1748       assert(current_method != NULL, "old and but not obsolete, so should exist");
1749       new_id = Method::make_jmethod_id(ik->class_loader_data(), current_method);
1750     } else {
1751       // It is the current version of the method or an obsolete method,
1752       // use the version passed in
1753       new_id = Method::make_jmethod_id(ik->class_loader_data(), method_h());
1754     }
1755 
1756     if (Threads::number_of_threads() == 0 ||
1757         SafepointSynchronize::is_at_safepoint()) {
1758       // we're single threaded or at a safepoint - no locking needed
1759       id = get_jmethod_id_fetch_or_update(ik, idnum, new_id, new_jmeths,
1760                                           &to_dealloc_id, &to_dealloc_jmeths);
1761     } else {
1762       MutexLocker ml(JmethodIdCreation_lock);
1763       id = get_jmethod_id_fetch_or_update(ik, idnum, new_id, new_jmeths,
1764                                           &to_dealloc_id, &to_dealloc_jmeths);
1765     }
1766 
1767     // The lock has been dropped so we can free resources.
1768     // Free up either the old cache or the new cache if we allocated one.
1769     if (to_dealloc_jmeths != NULL) {
1770       FreeHeap(to_dealloc_jmeths);
1771     }
1772     // free up the new ID since it wasn't needed
1773     if (to_dealloc_id != NULL) {
1774       Method::destroy_jmethod_id(ik->class_loader_data(), to_dealloc_id);
1775     }
1776   }
1777   return id;
1778 }
1779 
1780 // Figure out how many jmethodIDs haven't been allocated, and make
1781 // sure space for them is pre-allocated.  This makes getting all
1782 // method ids much, much faster with classes with more than 8
1783 // methods, and has a *substantial* effect on performance with jvmti
1784 // code that loads all jmethodIDs for all classes.
1785 void InstanceKlass::ensure_space_for_methodids(int start_offset) {
1786   int new_jmeths = 0;
1787   int length = methods()->length();
1788   for (int index = start_offset; index < length; index++) {
1789     Method* m = methods()->at(index);
1790     jmethodID id = m->find_jmethod_id_or_null();
1791     if (id == NULL) {
1792       new_jmeths++;
1793     }
1794   }
1795   if (new_jmeths != 0) {
1796     Method::ensure_jmethod_ids(class_loader_data(), new_jmeths);
1797   }
1798 }
1799 
1800 // Common code to fetch the jmethodID from the cache or update the
1801 // cache with the new jmethodID. This function should never do anything
1802 // that causes the caller to go to a safepoint or we can deadlock with
1803 // the VMThread or have cache consistency issues.
1804 //
1805 jmethodID InstanceKlass::get_jmethod_id_fetch_or_update(
1806             InstanceKlass* ik, size_t idnum, jmethodID new_id,
1807             jmethodID* new_jmeths, jmethodID* to_dealloc_id_p,
1808             jmethodID** to_dealloc_jmeths_p) {
1809   assert(new_id != NULL, "sanity check");
1810   assert(to_dealloc_id_p != NULL, "sanity check");
1811   assert(to_dealloc_jmeths_p != NULL, "sanity check");
1812   assert(Threads::number_of_threads() == 0 ||
1813          SafepointSynchronize::is_at_safepoint() ||
1814          JmethodIdCreation_lock->owned_by_self(), "sanity check");
1815 
1816   // reacquire the cache - we are locked, single threaded or at a safepoint
1817   jmethodID* jmeths = ik->methods_jmethod_ids_acquire();
1818   jmethodID  id     = NULL;
1819   size_t     length = 0;
1820 
1821   if (jmeths == NULL ||                         // no cache yet
1822       (length = (size_t)jmeths[0]) <= idnum) {  // cache is too short
1823     if (jmeths != NULL) {
1824       // copy any existing entries from the old cache
1825       for (size_t index = 0; index < length; index++) {
1826         new_jmeths[index+1] = jmeths[index+1];
1827       }
1828       *to_dealloc_jmeths_p = jmeths;  // save old cache for later delete
1829     }
1830     ik->release_set_methods_jmethod_ids(jmeths = new_jmeths);
1831   } else {
1832     // fetch jmethodID (if any) from the existing cache
1833     id = jmeths[idnum+1];
1834     *to_dealloc_jmeths_p = new_jmeths;  // save new cache for later delete
1835   }
1836   if (id == NULL) {
1837     // No matching jmethodID in the existing cache or we have a new
1838     // cache or we just grew the cache. This cache write is done here
1839     // by the first thread to win the foot race because a jmethodID
1840     // needs to be unique once it is generally available.
1841     id = new_id;
1842 
1843     // The jmethodID cache can be read while unlocked so we have to
1844     // make sure the new jmethodID is complete before installing it
1845     // in the cache.
1846     OrderAccess::release_store_ptr(&jmeths[idnum+1], id);
1847   } else {
1848     *to_dealloc_id_p = new_id; // save new id for later delete
1849   }
1850   return id;
1851 }
1852 
1853 
1854 // Common code to get the jmethodID cache length and the jmethodID
1855 // value at index idnum if there is one.
1856 //
1857 void InstanceKlass::get_jmethod_id_length_value(jmethodID* cache,
1858        size_t idnum, size_t *length_p, jmethodID* id_p) {
1859   assert(cache != NULL, "sanity check");
1860   assert(length_p != NULL, "sanity check");
1861   assert(id_p != NULL, "sanity check");
1862 
1863   // cache size is stored in element[0], other elements offset by one
1864   *length_p = (size_t)cache[0];
1865   if (*length_p <= idnum) {  // cache is too short
1866     *id_p = NULL;
1867   } else {
1868     *id_p = cache[idnum+1];  // fetch jmethodID (if any)
1869   }
1870 }
1871 
1872 
1873 // Lookup a jmethodID, NULL if not found.  Do no blocking, no allocations, no handles
1874 jmethodID InstanceKlass::jmethod_id_or_null(Method* method) {
1875   size_t idnum = (size_t)method->method_idnum();
1876   jmethodID* jmeths = methods_jmethod_ids_acquire();
1877   size_t length;                                // length assigned as debugging crumb
1878   jmethodID id = NULL;
1879   if (jmeths != NULL &&                         // If there is a cache
1880       (length = (size_t)jmeths[0]) > idnum) {   // and if it is long enough,
1881     id = jmeths[idnum+1];                       // Look up the id (may be NULL)
1882   }
1883   return id;
1884 }
1885 
1886 inline DependencyContext InstanceKlass::dependencies() {
1887   DependencyContext dep_context(&_dep_context);
1888   return dep_context;
1889 }
1890 
1891 int InstanceKlass::mark_dependent_nmethods(KlassDepChange& changes) {
1892   return dependencies().mark_dependent_nmethods(changes);
1893 }
1894 
1895 void InstanceKlass::add_dependent_nmethod(nmethod* nm) {
1896   dependencies().add_dependent_nmethod(nm);
1897 }
1898 
1899 void InstanceKlass::remove_dependent_nmethod(nmethod* nm, bool delete_immediately) {
1900   dependencies().remove_dependent_nmethod(nm, delete_immediately);
1901 }
1902 
1903 #ifndef PRODUCT
1904 void InstanceKlass::print_dependent_nmethods(bool verbose) {
1905   dependencies().print_dependent_nmethods(verbose);
1906 }
1907 
1908 bool InstanceKlass::is_dependent_nmethod(nmethod* nm) {
1909   return dependencies().is_dependent_nmethod(nm);
1910 }
1911 #endif //PRODUCT
1912 
1913 void InstanceKlass::clean_weak_instanceklass_links(BoolObjectClosure* is_alive) {
1914   clean_implementors_list(is_alive);
1915   clean_method_data(is_alive);
1916 
1917   // Since GC iterates InstanceKlasses sequentially, it is safe to remove stale entries here.
1918   DependencyContext dep_context(&_dep_context);
1919   dep_context.expunge_stale_entries();
1920 }
1921 
1922 void InstanceKlass::clean_implementors_list(BoolObjectClosure* is_alive) {
1923   assert(class_loader_data()->is_alive(is_alive), "this klass should be live");
1924   if (is_interface()) {
1925     if (ClassUnloading) {
1926       Klass* impl = implementor();
1927       if (impl != NULL) {
1928         if (!impl->is_loader_alive(is_alive)) {
1929           // remove this guy
1930           Klass** klass = adr_implementor();
1931           assert(klass != NULL, "null klass");
1932           if (klass != NULL) {
1933             *klass = NULL;
1934           }
1935         }
1936       }
1937     }
1938   }
1939 }
1940 
1941 void InstanceKlass::clean_method_data(BoolObjectClosure* is_alive) {
1942   for (int m = 0; m < methods()->length(); m++) {
1943     MethodData* mdo = methods()->at(m)->method_data();
1944     if (mdo != NULL) {
1945       mdo->clean_method_data(is_alive);
1946     }
1947   }
1948 }
1949 
1950 bool InstanceKlass::supers_have_passed_fingerprint_checks() {
1951   if (java_super() != NULL && !java_super()->has_passed_fingerprint_check()) {
1952     ResourceMark rm;
1953     log_trace(class, fingerprint)("%s : super %s not fingerprinted", external_name(), java_super()->external_name());
1954     return false;
1955   }
1956 
1957   Array<Klass*>* local_interfaces = this->local_interfaces();
1958   if (local_interfaces != NULL) {
1959     int length = local_interfaces->length();
1960     for (int i = 0; i < length; i++) {
1961       InstanceKlass* intf = InstanceKlass::cast(local_interfaces->at(i));
1962       if (!intf->has_passed_fingerprint_check()) {
1963         ResourceMark rm;
1964         log_trace(class, fingerprint)("%s : interface %s not fingerprinted", external_name(), intf->external_name());
1965         return false;
1966       }
1967     }
1968   }
1969 
1970   return true;
1971 }
1972 
1973 bool InstanceKlass::should_store_fingerprint() {
1974 #if INCLUDE_AOT
1975   // We store the fingerprint into the InstanceKlass only in the following 2 cases:
1976   if (EnableJVMCI && !UseJVMCICompiler) {
1977     // (1) We are running AOT to generate a shared library.
1978     return true;
1979   }
1980   if (DumpSharedSpaces) {
1981     // (2) We are running -Xshare:dump to create a shared archive
1982     return true;
1983   }
1984 #endif
1985 
1986   // In all other cases we might set the _misc_has_passed_fingerprint_check bit,
1987   // but do not store the 64-bit fingerprint to save space.
1988   return false;
1989 }
1990 
1991 bool InstanceKlass::has_stored_fingerprint() const {
1992 #if INCLUDE_AOT
1993   return should_store_fingerprint() || is_shared();
1994 #else
1995   return false;
1996 #endif
1997 }
1998 
1999 uint64_t InstanceKlass::get_stored_fingerprint() const {
2000   address adr = adr_fingerprint();
2001   if (adr != NULL) {
2002     return (uint64_t)Bytes::get_native_u8(adr); // adr may not be 64-bit aligned
2003   }
2004   return 0;
2005 }
2006 
2007 void InstanceKlass::store_fingerprint(uint64_t fingerprint) {
2008   address adr = adr_fingerprint();
2009   if (adr != NULL) {
2010     Bytes::put_native_u8(adr, (u8)fingerprint); // adr may not be 64-bit aligned
2011 
2012     ResourceMark rm;
2013     log_trace(class, fingerprint)("stored as " PTR64_FORMAT " for class %s", fingerprint, external_name());
2014   }
2015 }
2016 
2017 static void remove_unshareable_in_class(Klass* k) {
2018   // remove klass's unshareable info
2019   k->remove_unshareable_info();
2020 }
2021 
2022 void InstanceKlass::remove_unshareable_info() {
2023   Klass::remove_unshareable_info();
2024   // Unlink the class
2025   if (is_linked()) {
2026     unlink_class();
2027   }
2028   init_implementor();
2029 
2030   constants()->remove_unshareable_info();
2031 
2032   assert(_dep_context == DependencyContext::EMPTY, "dependency context is not shareable");
2033 
2034   for (int i = 0; i < methods()->length(); i++) {
2035     Method* m = methods()->at(i);
2036     m->remove_unshareable_info();
2037   }
2038 
2039   // do array classes also.
2040   array_klasses_do(remove_unshareable_in_class);
2041 }
2042 
2043 static void restore_unshareable_in_class(Klass* k, TRAPS) {
2044   // Array classes have null protection domain.
2045   // --> see ArrayKlass::complete_create_array_klass()
2046   k->restore_unshareable_info(ClassLoaderData::the_null_class_loader_data(), Handle(), CHECK);
2047 }
2048 
2049 void InstanceKlass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain, TRAPS) {
2050   set_package(loader_data, CHECK);

2051   Klass::restore_unshareable_info(loader_data, protection_domain, CHECK);
2052 
2053   Array<Method*>* methods = this->methods();
2054   int num_methods = methods->length();
2055   for (int index2 = 0; index2 < num_methods; ++index2) {
2056     methodHandle m(THREAD, methods->at(index2));
2057     m->restore_unshareable_info(CHECK);
2058   }
2059   if (JvmtiExport::has_redefined_a_class()) {
2060     // Reinitialize vtable because RedefineClasses may have changed some
2061     // entries in this vtable for super classes so the CDS vtable might
2062     // point to old or obsolete entries.  RedefineClasses doesn't fix up
2063     // vtables in the shared system dictionary, only the main one.
2064     // It also redefines the itable too so fix that too.
2065     ResourceMark rm(THREAD);
2066     vtable()->initialize_vtable(false, CHECK);
2067     itable()->initialize_itable(false, CHECK);
2068   }
2069 
2070   // restore constant pool resolved references
2071   constants()->restore_unshareable_info(CHECK);
2072 
2073   array_klasses_do(restore_unshareable_in_class, CHECK);
2074 }
2075 
2076 // returns true IFF is_in_error_state() has been changed as a result of this call.
2077 bool InstanceKlass::check_sharing_error_state() {
2078   assert(DumpSharedSpaces, "should only be called during dumping");
2079   bool old_state = is_in_error_state();
2080 
2081   if (!is_in_error_state()) {
2082     bool bad = false;
2083     for (InstanceKlass* sup = java_super(); sup; sup = sup->java_super()) {
2084       if (sup->is_in_error_state()) {
2085         bad = true;
2086         break;
2087       }
2088     }
2089     if (!bad) {
2090       Array<Klass*>* interfaces = transitive_interfaces();
2091       for (int i = 0; i < interfaces->length(); i++) {
2092         Klass* iface = interfaces->at(i);
2093         if (InstanceKlass::cast(iface)->is_in_error_state()) {
2094           bad = true;
2095           break;
2096         }
2097       }
2098     }
2099 
2100     if (bad) {
2101       set_in_error_state();
2102     }
2103   }
2104 
2105   return (old_state != is_in_error_state());
2106 }
2107 
2108 #if INCLUDE_JVMTI
2109 static void clear_all_breakpoints(Method* m) {
2110   m->clear_all_breakpoints();
2111 }
2112 #endif
2113 
2114 void InstanceKlass::notify_unload_class(InstanceKlass* ik) {
2115   // notify the debugger
2116   if (JvmtiExport::should_post_class_unload()) {
2117     JvmtiExport::post_class_unload(ik);
2118   }
2119 
2120   // notify ClassLoadingService of class unload
2121   ClassLoadingService::notify_class_unloaded(ik);
2122 }
2123 
2124 void InstanceKlass::release_C_heap_structures(InstanceKlass* ik) {
2125   // Clean up C heap
2126   ik->release_C_heap_structures();
2127   ik->constants()->release_C_heap_structures();
2128 }
2129 
2130 void InstanceKlass::release_C_heap_structures() {
2131   // Can't release the constant pool here because the constant pool can be
2132   // deallocated separately from the InstanceKlass for default methods and
2133   // redefine classes.
2134 
2135   // Deallocate oop map cache
2136   if (_oop_map_cache != NULL) {
2137     delete _oop_map_cache;
2138     _oop_map_cache = NULL;
2139   }
2140 
2141   // Deallocate JNI identifiers for jfieldIDs
2142   JNIid::deallocate(jni_ids());
2143   set_jni_ids(NULL);
2144 
2145   jmethodID* jmeths = methods_jmethod_ids_acquire();
2146   if (jmeths != (jmethodID*)NULL) {
2147     release_set_methods_jmethod_ids(NULL);
2148     FreeHeap(jmeths);
2149   }
2150 
2151   // Deallocate MemberNameTable
2152   {
2153     Mutex* lock_or_null = SafepointSynchronize::is_at_safepoint() ? NULL : MemberNameTable_lock;
2154     MutexLockerEx ml(lock_or_null, Mutex::_no_safepoint_check_flag);
2155     MemberNameTable* mnt = member_names();
2156     if (mnt != NULL) {
2157       delete mnt;
2158       set_member_names(NULL);
2159     }
2160   }
2161 
2162   // Release dependencies.
2163   // It is desirable to use DC::remove_all_dependents() here, but, unfortunately,
2164   // it is not safe (see JDK-8143408). The problem is that the klass dependency
2165   // context can contain live dependencies, since there's a race between nmethod &
2166   // klass unloading. If the klass is dead when nmethod unloading happens, relevant
2167   // dependencies aren't removed from the context associated with the class (see
2168   // nmethod::flush_dependencies). It ends up during klass unloading as seemingly
2169   // live dependencies pointing to unloaded nmethods and causes a crash in
2170   // DC::remove_all_dependents() when it touches unloaded nmethod.
2171   dependencies().wipe();
2172 
2173 #if INCLUDE_JVMTI
2174   // Deallocate breakpoint records
2175   if (breakpoints() != 0x0) {
2176     methods_do(clear_all_breakpoints);
2177     assert(breakpoints() == 0x0, "should have cleared breakpoints");
2178   }
2179 
2180   // deallocate the cached class file
2181   if (_cached_class_file != NULL && !MetaspaceShared::is_in_shared_space(_cached_class_file)) {
2182     os::free(_cached_class_file);
2183     _cached_class_file = NULL;
2184   }
2185 #endif
2186 
2187   // Decrement symbol reference counts associated with the unloaded class.
2188   if (_name != NULL) _name->decrement_refcount();
2189   // unreference array name derived from this class name (arrays of an unloaded
2190   // class can't be referenced anymore).
2191   if (_array_name != NULL)  _array_name->decrement_refcount();
2192   if (_source_debug_extension != NULL) FREE_C_HEAP_ARRAY(char, _source_debug_extension);
2193 
2194   assert(_total_instanceKlass_count >= 1, "Sanity check");
2195   Atomic::dec(&_total_instanceKlass_count);
2196 }
2197 
2198 void InstanceKlass::set_source_debug_extension(const char* array, int length) {
2199   if (array == NULL) {
2200     _source_debug_extension = NULL;
2201   } else {
2202     // Adding one to the attribute length in order to store a null terminator
2203     // character could cause an overflow because the attribute length is
2204     // already coded with an u4 in the classfile, but in practice, it's
2205     // unlikely to happen.
2206     assert((length+1) > length, "Overflow checking");
2207     char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass);
2208     for (int i = 0; i < length; i++) {
2209       sde[i] = array[i];
2210     }
2211     sde[length] = '\0';
2212     _source_debug_extension = sde;
2213   }
2214 }
2215 
2216 address InstanceKlass::static_field_addr(int offset) {
2217   return (address)(offset + InstanceMirrorKlass::offset_of_static_fields() + cast_from_oop<intptr_t>(java_mirror()));
2218 }
2219 
2220 
2221 const char* InstanceKlass::signature_name() const {
2222   int hash_len = 0;
2223   char hash_buf[40];
2224 
2225   // If this is an anonymous class, append a hash to make the name unique
2226   if (is_anonymous()) {
2227     intptr_t hash = (java_mirror() != NULL) ? java_mirror()->identity_hash() : 0;
2228     jio_snprintf(hash_buf, sizeof(hash_buf), "/" UINTX_FORMAT, (uintx)hash);
2229     hash_len = (int)strlen(hash_buf);
2230   }
2231 
2232   // Get the internal name as a c string
2233   const char* src = (const char*) (name()->as_C_string());
2234   const int src_length = (int)strlen(src);
2235 
2236   char* dest = NEW_RESOURCE_ARRAY(char, src_length + hash_len + 3);
2237 
2238   // Add L as type indicator
2239   int dest_index = 0;
2240   dest[dest_index++] = 'L';
2241 
2242   // Add the actual class name
2243   for (int src_index = 0; src_index < src_length; ) {
2244     dest[dest_index++] = src[src_index++];
2245   }
2246 
2247   // If we have a hash, append it
2248   for (int hash_index = 0; hash_index < hash_len; ) {
2249     dest[dest_index++] = hash_buf[hash_index++];
2250   }
2251 
2252   // Add the semicolon and the NULL
2253   dest[dest_index++] = ';';
2254   dest[dest_index] = '\0';
2255   return dest;
2256 }
2257 
2258 // Used to obtain the package name from a fully qualified class name.
2259 Symbol* InstanceKlass::package_from_name(const Symbol* name, TRAPS) {
2260   if (name == NULL) {
2261     return NULL;
2262   } else {
2263     if (name->utf8_length() <= 0) {
2264       return NULL;
2265     }
2266     ResourceMark rm;
2267     const char* package_name = ClassLoader::package_from_name((const char*) name->as_C_string());
2268     if (package_name == NULL) {
2269       return NULL;
2270     }
2271     Symbol* pkg_name = SymbolTable::new_symbol(package_name, THREAD);
2272     return pkg_name;
2273   }
2274 }
2275 
2276 ModuleEntry* InstanceKlass::module() const {
2277   if (!in_unnamed_package()) {
2278     return _package_entry->module();
2279   }
2280   const Klass* host = host_klass();
2281   if (host == NULL) {
2282     return class_loader_data()->modules()->unnamed_module();
2283   }
2284   return host->class_loader_data()->modules()->unnamed_module();
2285 }
2286 
2287 void InstanceKlass::set_package(ClassLoaderData* loader_data, TRAPS) {
2288 
2289   // ensure java/ packages only loaded by boot or platform builtin loaders
2290   Handle class_loader(THREAD, loader_data->class_loader());
2291   check_prohibited_package(name(), class_loader, CHECK);
2292 
2293   TempNewSymbol pkg_name = package_from_name(name(), CHECK);
2294 
2295   if (pkg_name != NULL && loader_data != NULL) {
2296 
2297     // Find in class loader's package entry table.
2298     _package_entry = loader_data->packages()->lookup_only(pkg_name);
2299 
2300     // If the package name is not found in the loader's package
2301     // entry table, it is an indication that the package has not
2302     // been defined. Consider it defined within the unnamed module.
2303     if (_package_entry == NULL) {
2304       ResourceMark rm;
2305 
2306       if (!ModuleEntryTable::javabase_defined()) {
2307         // Before java.base is defined during bootstrapping, define all packages in
2308         // the java.base module.  If a non-java.base package is erroneously placed
2309         // in the java.base module it will be caught later when java.base
2310         // is defined by ModuleEntryTable::verify_javabase_packages check.
2311         assert(ModuleEntryTable::javabase_moduleEntry() != NULL, JAVA_BASE_NAME " module is NULL");
2312         _package_entry = loader_data->packages()->lookup(pkg_name, ModuleEntryTable::javabase_moduleEntry());
2313       } else {
2314         assert(loader_data->modules()->unnamed_module() != NULL, "unnamed module is NULL");
2315         _package_entry = loader_data->packages()->lookup(pkg_name,
2316                                                          loader_data->modules()->unnamed_module());
2317       }
2318 
2319       // A package should have been successfully created
2320       assert(_package_entry != NULL, "Package entry for class %s not found, loader %s",
2321              name()->as_C_string(), loader_data->loader_name());
2322     }
2323 
2324     if (log_is_enabled(Debug, modules)) {
2325       ResourceMark rm;
2326       ModuleEntry* m = _package_entry->module();
2327       log_trace(modules)("Setting package: class: %s, package: %s, loader: %s, module: %s",
2328                          external_name(),
2329                          pkg_name->as_C_string(),
2330                          loader_data->loader_name(),
2331                          (m->is_named() ? m->name()->as_C_string() : UNNAMED_MODULE));
2332     }
2333   } else {
2334     ResourceMark rm;
2335     log_trace(modules)("Setting package: class: %s, package: unnamed, loader: %s, module: %s",
2336                        external_name(),
2337                        (loader_data != NULL) ? loader_data->loader_name() : "NULL",
2338                        UNNAMED_MODULE);
2339   }
2340 }
2341 
2342 
2343 // different versions of is_same_class_package
2344 
2345 bool InstanceKlass::is_same_class_package(const Klass* class2) const {
2346   oop classloader1 = this->class_loader();
2347   PackageEntry* classpkg1 = this->package();
2348   if (class2->is_objArray_klass()) {
2349     class2 = ObjArrayKlass::cast(class2)->bottom_klass();
2350   }
2351 
2352   oop classloader2;
2353   PackageEntry* classpkg2;
2354   if (class2->is_instance_klass()) {
2355     classloader2 = class2->class_loader();
2356     classpkg2 = class2->package();
2357   } else {
2358     assert(class2->is_typeArray_klass(), "should be type array");
2359     classloader2 = NULL;
2360     classpkg2 = NULL;
2361   }
2362 
2363   // Same package is determined by comparing class loader
2364   // and package entries. Both must be the same. This rule
2365   // applies even to classes that are defined in the unnamed
2366   // package, they still must have the same class loader.
2367   if ((classloader1 == classloader2) && (classpkg1 == classpkg2)) {
2368     return true;
2369   }
2370 
2371   return false;
2372 }
2373 
2374 bool InstanceKlass::is_same_class_package(oop other_class_loader,
2375                                           const Symbol* other_class_name) const {
2376   oop this_class_loader = class_loader();
2377   const Symbol* const this_class_name = name();
2378 
2379   return InstanceKlass::is_same_class_package(this_class_loader,
2380                                              this_class_name,
2381                                              other_class_loader,
2382                                              other_class_name);
2383 }
2384 
2385 // return true if two classes are in the same package, classloader
2386 // and classname information is enough to determine a class's package
2387 bool InstanceKlass::is_same_class_package(oop class_loader1, const Symbol* class_name1,
2388                                           oop class_loader2, const Symbol* class_name2) {
2389   if (class_loader1 != class_loader2) {
2390     return false;
2391   } else if (class_name1 == class_name2) {
2392     return true;
2393   } else {
2394     ResourceMark rm;
2395 
2396     bool bad_class_name = false;
2397     const char* name1 = ClassLoader::package_from_name((const char*) class_name1->as_C_string(), &bad_class_name);
2398     if (bad_class_name) {
2399       return false;
2400     }
2401 
2402     const char* name2 = ClassLoader::package_from_name((const char*) class_name2->as_C_string(), &bad_class_name);
2403     if (bad_class_name) {
2404       return false;
2405     }
2406 
2407     if ((name1 == NULL) || (name2 == NULL)) {
2408       // One of the two doesn't have a package.  Only return true
2409       // if the other one also doesn't have a package.
2410       return name1 == name2;
2411     }
2412 
2413     // Check that package is identical
2414     return (strcmp(name1, name2) == 0);
2415   }
2416 }
2417 
2418 // Returns true iff super_method can be overridden by a method in targetclassname
2419 // See JLS 3rd edition 8.4.6.1
2420 // Assumes name-signature match
2421 // "this" is InstanceKlass of super_method which must exist
2422 // note that the InstanceKlass of the method in the targetclassname has not always been created yet
2423 bool InstanceKlass::is_override(const methodHandle& super_method, Handle targetclassloader, Symbol* targetclassname, TRAPS) {
2424    // Private methods can not be overridden
2425    if (super_method->is_private()) {
2426      return false;
2427    }
2428    // If super method is accessible, then override
2429    if ((super_method->is_protected()) ||
2430        (super_method->is_public())) {
2431      return true;
2432    }
2433    // Package-private methods are not inherited outside of package
2434    assert(super_method->is_package_private(), "must be package private");
2435    return(is_same_class_package(targetclassloader(), targetclassname));
2436 }
2437 
2438 /* defined for now in jvm.cpp, for historical reasons *--
2439 Klass* InstanceKlass::compute_enclosing_class_impl(InstanceKlass* self,
2440                                                      Symbol*& simple_name_result, TRAPS) {
2441   ...
2442 }
2443 */
2444 
2445 // Only boot and platform class loaders can define classes in "java/" packages.
2446 void InstanceKlass::check_prohibited_package(Symbol* class_name,
2447                                              Handle class_loader,
2448                                              TRAPS) {
2449   ResourceMark rm(THREAD);
2450   if (!class_loader.is_null() &&
2451       !SystemDictionary::is_platform_class_loader(class_loader()) &&
2452       class_name != NULL &&
2453       strncmp(class_name->as_C_string(), JAVAPKG, JAVAPKG_LEN) == 0) {
2454     TempNewSymbol pkg_name = InstanceKlass::package_from_name(class_name, CHECK);
2455     assert(pkg_name != NULL, "Error in parsing package name starting with 'java/'");
2456     char* name = pkg_name->as_C_string();
2457     const char* class_loader_name = SystemDictionary::loader_name(class_loader());
2458     StringUtils::replace_no_expand(name, "/", ".");
2459     const char* msg_text1 = "Class loader (instance of): ";
2460     const char* msg_text2 = " tried to load prohibited package name: ";
2461     size_t len = strlen(msg_text1) + strlen(class_loader_name) + strlen(msg_text2) + strlen(name) + 1;
2462     char* message = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, len);
2463     jio_snprintf(message, len, "%s%s%s%s", msg_text1, class_loader_name, msg_text2, name);
2464     THROW_MSG(vmSymbols::java_lang_SecurityException(), message);
2465   }
2466   return;
2467 }
2468 
2469 // tell if two classes have the same enclosing class (at package level)
2470 bool InstanceKlass::is_same_package_member_impl(const InstanceKlass* class1,
2471                                                 const Klass* class2,
2472                                                 TRAPS) {
2473   if (class2 == class1) return true;
2474   if (!class2->is_instance_klass())  return false;
2475 
2476   // must be in same package before we try anything else
2477   if (!class1->is_same_class_package(class2))
2478     return false;
2479 
2480   // As long as there is an outer1.getEnclosingClass,
2481   // shift the search outward.
2482   const InstanceKlass* outer1 = class1;
2483   for (;;) {
2484     // As we walk along, look for equalities between outer1 and class2.
2485     // Eventually, the walks will terminate as outer1 stops
2486     // at the top-level class around the original class.
2487     bool ignore_inner_is_member;
2488     const Klass* next = outer1->compute_enclosing_class(&ignore_inner_is_member,
2489                                                   CHECK_false);
2490     if (next == NULL)  break;
2491     if (next == class2)  return true;
2492     outer1 = InstanceKlass::cast(next);
2493   }
2494 
2495   // Now do the same for class2.
2496   const InstanceKlass* outer2 = InstanceKlass::cast(class2);
2497   for (;;) {
2498     bool ignore_inner_is_member;
2499     Klass* next = outer2->compute_enclosing_class(&ignore_inner_is_member,
2500                                                     CHECK_false);
2501     if (next == NULL)  break;
2502     // Might as well check the new outer against all available values.
2503     if (next == class1)  return true;
2504     if (next == outer1)  return true;
2505     outer2 = InstanceKlass::cast(next);
2506   }
2507 
2508   // If by this point we have not found an equality between the
2509   // two classes, we know they are in separate package members.
2510   return false;
2511 }
2512 
2513 bool InstanceKlass::find_inner_classes_attr(const InstanceKlass* k, int* ooff, int* noff, TRAPS) {
2514   constantPoolHandle i_cp(THREAD, k->constants());
2515   for (InnerClassesIterator iter(k); !iter.done(); iter.next()) {
2516     int ioff = iter.inner_class_info_index();
2517     if (ioff != 0) {
2518       // Check to see if the name matches the class we're looking for
2519       // before attempting to find the class.
2520       if (i_cp->klass_name_at_matches(k, ioff)) {
2521         Klass* inner_klass = i_cp->klass_at(ioff, CHECK_false);
2522         if (k == inner_klass) {
2523           *ooff = iter.outer_class_info_index();
2524           *noff = iter.inner_name_index();
2525           return true;
2526         }
2527       }
2528     }
2529   }
2530   return false;
2531 }
2532 
2533 InstanceKlass* InstanceKlass::compute_enclosing_class_impl(const InstanceKlass* k,
2534                                                            bool* inner_is_member,
2535                                                            TRAPS) {
2536   InstanceKlass* outer_klass = NULL;
2537   *inner_is_member = false;
2538   int ooff = 0, noff = 0;
2539   if (find_inner_classes_attr(k, &ooff, &noff, THREAD)) {
2540     constantPoolHandle i_cp(THREAD, k->constants());
2541     if (ooff != 0) {
2542       Klass* ok = i_cp->klass_at(ooff, CHECK_NULL);
2543       outer_klass = InstanceKlass::cast(ok);
2544       *inner_is_member = true;
2545     }
2546     if (NULL == outer_klass) {
2547       // It may be anonymous; try for that.
2548       int encl_method_class_idx = k->enclosing_method_class_index();
2549       if (encl_method_class_idx != 0) {
2550         Klass* ok = i_cp->klass_at(encl_method_class_idx, CHECK_NULL);
2551         outer_klass = InstanceKlass::cast(ok);
2552         *inner_is_member = false;
2553       }
2554     }
2555   }
2556 
2557   // If no inner class attribute found for this class.
2558   if (NULL == outer_klass) return NULL;
2559 
2560   // Throws an exception if outer klass has not declared k as an inner klass
2561   // We need evidence that each klass knows about the other, or else
2562   // the system could allow a spoof of an inner class to gain access rights.
2563   Reflection::check_for_inner_class(outer_klass, k, *inner_is_member, CHECK_NULL);
2564   return outer_klass;
2565 }
2566 
2567 jint InstanceKlass::compute_modifier_flags(TRAPS) const {
2568   jint access = access_flags().as_int();
2569 
2570   // But check if it happens to be member class.
2571   InnerClassesIterator iter(this);

2572   for (; !iter.done(); iter.next()) {
2573     int ioff = iter.inner_class_info_index();
2574     // Inner class attribute can be zero, skip it.
2575     // Strange but true:  JVM spec. allows null inner class refs.
2576     if (ioff == 0) continue;
2577 
2578     // only look at classes that are already loaded
2579     // since we are looking for the flags for our self.
2580     Symbol* inner_name = constants()->klass_name_at(ioff);
2581     if ((name() == inner_name)) {
2582       // This is really a member class.
2583       access = iter.inner_access_flags();
2584       break;
2585     }
2586   }
2587   // Remember to strip ACC_SUPER bit
2588   return (access & (~JVM_ACC_SUPER)) & JVM_ACC_WRITTEN_FLAGS;
2589 }
2590 
2591 jint InstanceKlass::jvmti_class_status() const {
2592   jint result = 0;
2593 
2594   if (is_linked()) {
2595     result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED;
2596   }
2597 
2598   if (is_initialized()) {
2599     assert(is_linked(), "Class status is not consistent");
2600     result |= JVMTI_CLASS_STATUS_INITIALIZED;
2601   }
2602   if (is_in_error_state()) {
2603     result |= JVMTI_CLASS_STATUS_ERROR;
2604   }
2605   return result;
2606 }
2607 
2608 Method* InstanceKlass::method_at_itable(Klass* holder, int index, TRAPS) {
2609   itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2610   int method_table_offset_in_words = ioe->offset()/wordSize;
2611   int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words())
2612                        / itableOffsetEntry::size();
2613 
2614   for (int cnt = 0 ; ; cnt ++, ioe ++) {
2615     // If the interface isn't implemented by the receiver class,
2616     // the VM should throw IncompatibleClassChangeError.
2617     if (cnt >= nof_interfaces) {
2618       THROW_NULL(vmSymbols::java_lang_IncompatibleClassChangeError());
2619     }
2620 
2621     Klass* ik = ioe->interface_klass();
2622     if (ik == holder) break;
2623   }
2624 
2625   itableMethodEntry* ime = ioe->first_method_entry(this);
2626   Method* m = ime[index].method();
2627   if (m == NULL) {
2628     THROW_NULL(vmSymbols::java_lang_AbstractMethodError());
2629   }
2630   return m;
2631 }
2632 
2633 
2634 #if INCLUDE_JVMTI
2635 // update default_methods for redefineclasses for methods that are
2636 // not yet in the vtable due to concurrent subclass define and superinterface
2637 // redefinition
2638 // Note: those in the vtable, should have been updated via adjust_method_entries
2639 void InstanceKlass::adjust_default_methods(InstanceKlass* holder, bool* trace_name_printed) {
2640   // search the default_methods for uses of either obsolete or EMCP methods
2641   if (default_methods() != NULL) {
2642     for (int index = 0; index < default_methods()->length(); index ++) {
2643       Method* old_method = default_methods()->at(index);
2644       if (old_method == NULL || old_method->method_holder() != holder || !old_method->is_old()) {
2645         continue; // skip uninteresting entries
2646       }
2647       assert(!old_method->is_deleted(), "default methods may not be deleted");
2648 
2649       Method* new_method = holder->method_with_idnum(old_method->orig_method_idnum());
2650 
2651       assert(new_method != NULL, "method_with_idnum() should not be NULL");
2652       assert(old_method != new_method, "sanity check");
2653 
2654       default_methods()->at_put(index, new_method);
2655       if (log_is_enabled(Info, redefine, class, update)) {
2656         ResourceMark rm;
2657         if (!(*trace_name_printed)) {
2658           log_info(redefine, class, update)
2659             ("adjust: klassname=%s default methods from name=%s",
2660              external_name(), old_method->method_holder()->external_name());
2661           *trace_name_printed = true;
2662         }
2663         log_debug(redefine, class, update, vtables)
2664           ("default method update: %s(%s) ",
2665            new_method->name()->as_C_string(), new_method->signature()->as_C_string());
2666       }
2667     }
2668   }
2669 }
2670 #endif // INCLUDE_JVMTI
2671 
2672 // On-stack replacement stuff
2673 void InstanceKlass::add_osr_nmethod(nmethod* n) {
2674   // only one compilation can be active
2675   {
2676     // This is a short non-blocking critical region, so the no safepoint check is ok.
2677     MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2678     assert(n->is_osr_method(), "wrong kind of nmethod");
2679     n->set_osr_link(osr_nmethods_head());
2680     set_osr_nmethods_head(n);
2681     // Raise the highest osr level if necessary
2682     if (TieredCompilation) {
2683       Method* m = n->method();
2684       m->set_highest_osr_comp_level(MAX2(m->highest_osr_comp_level(), n->comp_level()));
2685     }
2686   }
2687 
2688   // Get rid of the osr methods for the same bci that have lower levels.
2689   if (TieredCompilation) {
2690     for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) {
2691       nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true);
2692       if (inv != NULL && inv->is_in_use()) {
2693         inv->make_not_entrant();
2694       }
2695     }
2696   }
2697 }
2698 
2699 // Remove osr nmethod from the list. Return true if found and removed.
2700 bool InstanceKlass::remove_osr_nmethod(nmethod* n) {
2701   // This is a short non-blocking critical region, so the no safepoint check is ok.
2702   MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2703   assert(n->is_osr_method(), "wrong kind of nmethod");
2704   nmethod* last = NULL;
2705   nmethod* cur  = osr_nmethods_head();
2706   int max_level = CompLevel_none;  // Find the max comp level excluding n
2707   Method* m = n->method();
2708   // Search for match
2709   bool found = false;
2710   while(cur != NULL && cur != n) {
2711     if (TieredCompilation && m == cur->method()) {
2712       // Find max level before n
2713       max_level = MAX2(max_level, cur->comp_level());
2714     }
2715     last = cur;
2716     cur = cur->osr_link();
2717   }
2718   nmethod* next = NULL;
2719   if (cur == n) {
2720     found = true;
2721     next = cur->osr_link();
2722     if (last == NULL) {
2723       // Remove first element
2724       set_osr_nmethods_head(next);
2725     } else {
2726       last->set_osr_link(next);
2727     }
2728   }
2729   n->set_osr_link(NULL);
2730   if (TieredCompilation) {
2731     cur = next;
2732     while (cur != NULL) {
2733       // Find max level after n
2734       if (m == cur->method()) {
2735         max_level = MAX2(max_level, cur->comp_level());
2736       }
2737       cur = cur->osr_link();
2738     }
2739     m->set_highest_osr_comp_level(max_level);
2740   }
2741   return found;
2742 }
2743 
2744 int InstanceKlass::mark_osr_nmethods(const Method* m) {
2745   // This is a short non-blocking critical region, so the no safepoint check is ok.
2746   MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2747   nmethod* osr = osr_nmethods_head();
2748   int found = 0;
2749   while (osr != NULL) {
2750     assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
2751     if (osr->method() == m) {
2752       osr->mark_for_deoptimization();
2753       found++;
2754     }
2755     osr = osr->osr_link();
2756   }
2757   return found;
2758 }
2759 
2760 nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const {
2761   // This is a short non-blocking critical region, so the no safepoint check is ok.
2762   MutexLockerEx ml(OsrList_lock, Mutex::_no_safepoint_check_flag);
2763   nmethod* osr = osr_nmethods_head();
2764   nmethod* best = NULL;
2765   while (osr != NULL) {
2766     assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
2767     // There can be a time when a c1 osr method exists but we are waiting
2768     // for a c2 version. When c2 completes its osr nmethod we will trash
2769     // the c1 version and only be able to find the c2 version. However
2770     // while we overflow in the c1 code at back branches we don't want to
2771     // try and switch to the same code as we are already running
2772 
2773     if (osr->method() == m &&
2774         (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) {
2775       if (match_level) {
2776         if (osr->comp_level() == comp_level) {
2777           // Found a match - return it.
2778           return osr;
2779         }
2780       } else {
2781         if (best == NULL || (osr->comp_level() > best->comp_level())) {
2782           if (osr->comp_level() == CompLevel_highest_tier) {
2783             // Found the best possible - return it.
2784             return osr;
2785           }
2786           best = osr;
2787         }
2788       }
2789     }
2790     osr = osr->osr_link();
2791   }
2792   if (best != NULL && best->comp_level() >= comp_level && match_level == false) {
2793     return best;
2794   }
2795   return NULL;
2796 }
2797 
2798 bool InstanceKlass::add_member_name(Handle mem_name) {
2799   jweak mem_name_wref = JNIHandles::make_weak_global(mem_name);
2800   MutexLocker ml(MemberNameTable_lock);
2801   DEBUG_ONLY(NoSafepointVerifier nsv);
2802 
2803   // Check if method has been redefined while taking out MemberNameTable_lock, if so
2804   // return false.  We cannot cache obsolete methods. They will crash when the function
2805   // is called!
2806   Method* method = (Method*)java_lang_invoke_MemberName::vmtarget(mem_name());
2807   if (method->is_obsolete()) {
2808     return false;
2809   } else if (method->is_old()) {
2810     // Replace method with redefined version
2811     java_lang_invoke_MemberName::set_vmtarget(mem_name(), method_with_idnum(method->method_idnum()));
2812   }
2813 
2814   if (_member_names == NULL) {
2815     _member_names = new (ResourceObj::C_HEAP, mtClass) MemberNameTable(idnum_allocated_count());
2816   }
2817   _member_names->add_member_name(mem_name_wref);
2818   return true;
2819 }
2820 
2821 // -----------------------------------------------------------------------------------------------------
2822 // Printing
2823 
2824 #ifndef PRODUCT
2825 
2826 #define BULLET  " - "
2827 
2828 static const char* state_names[] = {
2829   "allocated", "loaded", "linked", "being_initialized", "fully_initialized", "initialization_error"
2830 };
2831 
2832 static void print_vtable(intptr_t* start, int len, outputStream* st) {
2833   for (int i = 0; i < len; i++) {
2834     intptr_t e = start[i];
2835     st->print("%d : " INTPTR_FORMAT, i, e);
2836     if (e != 0 && ((Metadata*)e)->is_metaspace_object()) {
2837       st->print(" ");
2838       ((Metadata*)e)->print_value_on(st);
2839     }
2840     st->cr();
2841   }
2842 }
2843 
2844 static void print_vtable(vtableEntry* start, int len, outputStream* st) {
2845   return print_vtable(reinterpret_cast<intptr_t*>(start), len, st);
2846 }
2847 
2848 void InstanceKlass::print_on(outputStream* st) const {
2849   assert(is_klass(), "must be klass");
2850   Klass::print_on(st);
2851 
2852   st->print(BULLET"instance size:     %d", size_helper());                        st->cr();
2853   st->print(BULLET"klass size:        %d", size());                               st->cr();
2854   st->print(BULLET"access:            "); access_flags().print_on(st);            st->cr();
2855   st->print(BULLET"state:             "); st->print_cr("%s", state_names[_init_state]);
2856   st->print(BULLET"name:              "); name()->print_value_on(st);             st->cr();
2857   st->print(BULLET"super:             "); super()->print_value_on_maybe_null(st); st->cr();
2858   st->print(BULLET"sub:               ");
2859   Klass* sub = subklass();
2860   int n;
2861   for (n = 0; sub != NULL; n++, sub = sub->next_sibling()) {
2862     if (n < MaxSubklassPrintSize) {
2863       sub->print_value_on(st);
2864       st->print("   ");
2865     }
2866   }
2867   if (n >= MaxSubklassPrintSize) st->print("(" INTX_FORMAT " more klasses...)", n - MaxSubklassPrintSize);
2868   st->cr();
2869 
2870   if (is_interface()) {
2871     st->print_cr(BULLET"nof implementors:  %d", nof_implementors());
2872     if (nof_implementors() == 1) {
2873       st->print_cr(BULLET"implementor:    ");
2874       st->print("   ");
2875       implementor()->print_value_on(st);
2876       st->cr();
2877     }
2878   }
2879 
2880   st->print(BULLET"arrays:            "); array_klasses()->print_value_on_maybe_null(st); st->cr();
2881   st->print(BULLET"methods:           "); methods()->print_value_on(st);                  st->cr();
2882   if (Verbose || WizardMode) {
2883     Array<Method*>* method_array = methods();
2884     for (int i = 0; i < method_array->length(); i++) {
2885       st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
2886     }
2887   }
2888   st->print(BULLET"method ordering:   "); method_ordering()->print_value_on(st);      st->cr();
2889   st->print(BULLET"default_methods:   "); default_methods()->print_value_on(st);      st->cr();
2890   if (Verbose && default_methods() != NULL) {
2891     Array<Method*>* method_array = default_methods();
2892     for (int i = 0; i < method_array->length(); i++) {
2893       st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
2894     }
2895   }
2896   if (default_vtable_indices() != NULL) {
2897     st->print(BULLET"default vtable indices:   "); default_vtable_indices()->print_value_on(st);       st->cr();
2898   }
2899   st->print(BULLET"local interfaces:  "); local_interfaces()->print_value_on(st);      st->cr();
2900   st->print(BULLET"trans. interfaces: "); transitive_interfaces()->print_value_on(st); st->cr();
2901   st->print(BULLET"constants:         "); constants()->print_value_on(st);         st->cr();
2902   if (class_loader_data() != NULL) {
2903     st->print(BULLET"class loader data:  ");
2904     class_loader_data()->print_value_on(st);
2905     st->cr();
2906   }
2907   st->print(BULLET"host class:        "); host_klass()->print_value_on_maybe_null(st); st->cr();
2908   if (source_file_name() != NULL) {
2909     st->print(BULLET"source file:       ");
2910     source_file_name()->print_value_on(st);
2911     st->cr();
2912   }
2913   if (source_debug_extension() != NULL) {
2914     st->print(BULLET"source debug extension:       ");
2915     st->print("%s", source_debug_extension());
2916     st->cr();
2917   }
2918   st->print(BULLET"class annotations:       "); class_annotations()->print_value_on(st); st->cr();
2919   st->print(BULLET"class type annotations:  "); class_type_annotations()->print_value_on(st); st->cr();
2920   st->print(BULLET"field annotations:       "); fields_annotations()->print_value_on(st); st->cr();
2921   st->print(BULLET"field type annotations:  "); fields_type_annotations()->print_value_on(st); st->cr();
2922   {
2923     bool have_pv = false;
2924     // previous versions are linked together through the InstanceKlass
2925     for (InstanceKlass* pv_node = previous_versions();
2926          pv_node != NULL;
2927          pv_node = pv_node->previous_versions()) {
2928       if (!have_pv)
2929         st->print(BULLET"previous version:  ");
2930       have_pv = true;
2931       pv_node->constants()->print_value_on(st);
2932     }
2933     if (have_pv) st->cr();
2934   }
2935 
2936   if (generic_signature() != NULL) {
2937     st->print(BULLET"generic signature: ");
2938     generic_signature()->print_value_on(st);
2939     st->cr();
2940   }
2941   st->print(BULLET"inner classes:     "); inner_classes()->print_value_on(st);     st->cr();
2942   st->print(BULLET"java mirror:       "); java_mirror()->print_value_on(st);       st->cr();
2943   st->print(BULLET"vtable length      %d  (start addr: " INTPTR_FORMAT ")", vtable_length(), p2i(start_of_vtable())); st->cr();
2944   if (vtable_length() > 0 && (Verbose || WizardMode))  print_vtable(start_of_vtable(), vtable_length(), st);
2945   st->print(BULLET"itable length      %d (start addr: " INTPTR_FORMAT ")", itable_length(), p2i(start_of_itable())); st->cr();
2946   if (itable_length() > 0 && (Verbose || WizardMode))  print_vtable(start_of_itable(), itable_length(), st);
2947   st->print_cr(BULLET"---- static fields (%d words):", static_field_size());
2948   FieldPrinter print_static_field(st);
2949   ((InstanceKlass*)this)->do_local_static_fields(&print_static_field);
2950   st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size());
2951   FieldPrinter print_nonstatic_field(st);
2952   InstanceKlass* ik = const_cast<InstanceKlass*>(this);
2953   ik->do_nonstatic_fields(&print_nonstatic_field);
2954 
2955   st->print(BULLET"non-static oop maps: ");
2956   OopMapBlock* map     = start_of_nonstatic_oop_maps();
2957   OopMapBlock* end_map = map + nonstatic_oop_map_count();
2958   while (map < end_map) {
2959     st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1));
2960     map++;
2961   }
2962   st->cr();
2963 }
2964 
2965 #endif //PRODUCT
2966 
2967 void InstanceKlass::print_value_on(outputStream* st) const {
2968   assert(is_klass(), "must be klass");
2969   if (Verbose || WizardMode)  access_flags().print_on(st);
2970   name()->print_value_on(st);
2971 }
2972 
2973 #ifndef PRODUCT
2974 
2975 void FieldPrinter::do_field(fieldDescriptor* fd) {
2976   _st->print(BULLET);
2977    if (_obj == NULL) {
2978      fd->print_on(_st);
2979      _st->cr();
2980    } else {
2981      fd->print_on_for(_st, _obj);
2982      _st->cr();
2983    }
2984 }
2985 
2986 
2987 void InstanceKlass::oop_print_on(oop obj, outputStream* st) {
2988   Klass::oop_print_on(obj, st);
2989 
2990   if (this == SystemDictionary::String_klass()) {
2991     typeArrayOop value  = java_lang_String::value(obj);
2992     juint        length = java_lang_String::length(obj);
2993     if (value != NULL &&
2994         value->is_typeArray() &&
2995         length <= (juint) value->length()) {
2996       st->print(BULLET"string: ");
2997       java_lang_String::print(obj, st);
2998       st->cr();
2999       if (!WizardMode)  return;  // that is enough
3000     }
3001   }
3002 
3003   st->print_cr(BULLET"---- fields (total size %d words):", oop_size(obj));
3004   FieldPrinter print_field(st, obj);
3005   do_nonstatic_fields(&print_field);
3006 
3007   if (this == SystemDictionary::Class_klass()) {
3008     st->print(BULLET"signature: ");
3009     java_lang_Class::print_signature(obj, st);
3010     st->cr();
3011     Klass* mirrored_klass = java_lang_Class::as_Klass(obj);
3012     st->print(BULLET"fake entry for mirror: ");
3013     mirrored_klass->print_value_on_maybe_null(st);
3014     st->cr();
3015     Klass* array_klass = java_lang_Class::array_klass(obj);
3016     st->print(BULLET"fake entry for array: ");
3017     array_klass->print_value_on_maybe_null(st);
3018     st->cr();
3019     st->print_cr(BULLET"fake entry for oop_size: %d", java_lang_Class::oop_size(obj));
3020     st->print_cr(BULLET"fake entry for static_oop_field_count: %d", java_lang_Class::static_oop_field_count(obj));
3021     Klass* real_klass = java_lang_Class::as_Klass(obj);
3022     if (real_klass != NULL && real_klass->is_instance_klass()) {
3023       InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field);
3024     }
3025   } else if (this == SystemDictionary::MethodType_klass()) {
3026     st->print(BULLET"signature: ");
3027     java_lang_invoke_MethodType::print_signature(obj, st);
3028     st->cr();
3029   }
3030 }
3031 
3032 #endif //PRODUCT
3033 
3034 void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) {
3035   st->print("a ");
3036   name()->print_value_on(st);
3037   obj->print_address_on(st);
3038   if (this == SystemDictionary::String_klass()
3039       && java_lang_String::value(obj) != NULL) {
3040     ResourceMark rm;
3041     int len = java_lang_String::length(obj);
3042     int plen = (len < 24 ? len : 12);
3043     char* str = java_lang_String::as_utf8_string(obj, 0, plen);
3044     st->print(" = \"%s\"", str);
3045     if (len > plen)
3046       st->print("...[%d]", len);
3047   } else if (this == SystemDictionary::Class_klass()) {
3048     Klass* k = java_lang_Class::as_Klass(obj);
3049     st->print(" = ");
3050     if (k != NULL) {
3051       k->print_value_on(st);
3052     } else {
3053       const char* tname = type2name(java_lang_Class::primitive_type(obj));
3054       st->print("%s", tname ? tname : "type?");
3055     }
3056   } else if (this == SystemDictionary::MethodType_klass()) {
3057     st->print(" = ");
3058     java_lang_invoke_MethodType::print_signature(obj, st);
3059   } else if (java_lang_boxing_object::is_instance(obj)) {
3060     st->print(" = ");
3061     java_lang_boxing_object::print(obj, st);
3062   } else if (this == SystemDictionary::LambdaForm_klass()) {
3063     oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj);
3064     if (vmentry != NULL) {
3065       st->print(" => ");
3066       vmentry->print_value_on(st);
3067     }
3068   } else if (this == SystemDictionary::MemberName_klass()) {
3069     Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj);
3070     if (vmtarget != NULL) {
3071       st->print(" = ");
3072       vmtarget->print_value_on(st);
3073     } else {
3074       java_lang_invoke_MemberName::clazz(obj)->print_value_on(st);
3075       st->print(".");
3076       java_lang_invoke_MemberName::name(obj)->print_value_on(st);
3077     }
3078   }
3079 }
3080 
3081 const char* InstanceKlass::internal_name() const {
3082   return external_name();
3083 }
3084 
3085 void InstanceKlass::print_loading_log(LogLevel::type type,
3086                                       ClassLoaderData* loader_data,
3087                                       const char* module_name,
3088                                       const ClassFileStream* cfs) const {
3089   ResourceMark rm;
3090   outputStream* log;
3091 
3092   assert(type == LogLevel::Info || type == LogLevel::Debug, "sanity");
3093 
3094   if (type == LogLevel::Info) {
3095     log = Log(class, load)::info_stream();
3096   } else {
3097     assert(type == LogLevel::Debug,
3098            "print_loading_log supports only Debug and Info levels");
3099     log = Log(class, load)::debug_stream();
3100   }
3101 
3102   // Name and class hierarchy info
3103   log->print("%s", external_name());
3104 
3105   // Source
3106   if (cfs != NULL) {
3107     if (cfs->source() != NULL) {
3108       if (module_name != NULL) {
3109         if (ClassLoader::is_jrt(cfs->source())) {
3110           log->print(" source: jrt:/%s", module_name);
3111         } else {
3112           log->print(" source: %s", cfs->source());
3113         }
3114       } else {
3115         log->print(" source: %s", cfs->source());
3116       }
3117     } else if (loader_data == ClassLoaderData::the_null_class_loader_data()) {
3118       Thread* THREAD = Thread::current();
3119       Klass* caller =
3120             THREAD->is_Java_thread()
3121                 ? ((JavaThread*)THREAD)->security_get_caller_class(1)
3122                 : NULL;
3123       // caller can be NULL, for example, during a JVMTI VM_Init hook
3124       if (caller != NULL) {
3125         log->print(" source: instance of %s", caller->external_name());
3126       } else {
3127         // source is unknown
3128       }
3129     } else {
3130       oop class_loader = loader_data->class_loader();
3131       log->print(" source: %s", class_loader->klass()->external_name());
3132     }
3133   } else {
3134     log->print(" source: shared objects file");
3135   }
3136 
3137   if (type == LogLevel::Debug) {
3138     // Class hierarchy info
3139     log->print(" klass: " INTPTR_FORMAT " super: " INTPTR_FORMAT,
3140                p2i(this),  p2i(superklass()));
3141 
3142     if (local_interfaces() != NULL && local_interfaces()->length() > 0) {
3143       log->print(" interfaces:");
3144       int length = local_interfaces()->length();
3145       for (int i = 0; i < length; i++) {
3146         log->print(" " INTPTR_FORMAT,
3147                    p2i(InstanceKlass::cast(local_interfaces()->at(i))));
3148       }
3149     }
3150 
3151     // Class loader
3152     log->print(" loader: [");
3153     loader_data->print_value_on(log);
3154     log->print("]");
3155 
3156     // Classfile checksum
3157     if (cfs) {
3158       log->print(" bytes: %d checksum: %08x",
3159                  cfs->length(),
3160                  ClassLoader::crc32(0, (const char*)cfs->buffer(),
3161                  cfs->length()));
3162     }
3163   }
3164   log->cr();
3165 }
3166 
3167 #if INCLUDE_SERVICES
3168 // Size Statistics
3169 void InstanceKlass::collect_statistics(KlassSizeStats *sz) const {
3170   Klass::collect_statistics(sz);
3171 
3172   sz->_inst_size  = wordSize * size_helper();
3173   sz->_vtab_bytes = wordSize * vtable_length();
3174   sz->_itab_bytes = wordSize * itable_length();
3175   sz->_nonstatic_oopmap_bytes = wordSize * nonstatic_oop_map_size();
3176 
3177   int n = 0;
3178   n += (sz->_methods_array_bytes         = sz->count_array(methods()));
3179   n += (sz->_method_ordering_bytes       = sz->count_array(method_ordering()));
3180   n += (sz->_local_interfaces_bytes      = sz->count_array(local_interfaces()));
3181   n += (sz->_transitive_interfaces_bytes = sz->count_array(transitive_interfaces()));
3182   n += (sz->_fields_bytes                = sz->count_array(fields()));
3183   n += (sz->_inner_classes_bytes         = sz->count_array(inner_classes()));
3184   sz->_ro_bytes += n;
3185 
3186   const ConstantPool* cp = constants();
3187   if (cp) {
3188     cp->collect_statistics(sz);
3189   }
3190 
3191   const Annotations* anno = annotations();
3192   if (anno) {
3193     anno->collect_statistics(sz);
3194   }
3195 
3196   const Array<Method*>* methods_array = methods();
3197   if (methods()) {
3198     for (int i = 0; i < methods_array->length(); i++) {
3199       Method* method = methods_array->at(i);
3200       if (method) {
3201         sz->_method_count ++;
3202         method->collect_statistics(sz);
3203       }
3204     }
3205   }
3206 }
3207 #endif // INCLUDE_SERVICES
3208 
3209 // Verification
3210 
3211 class VerifyFieldClosure: public OopClosure {
3212  protected:
3213   template <class T> void do_oop_work(T* p) {
3214     oop obj = oopDesc::load_decode_heap_oop(p);
3215     if (!obj->is_oop_or_null()) {
3216       tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p2i(p), p2i(obj));
3217       Universe::print_on(tty);
3218       guarantee(false, "boom");
3219     }
3220   }
3221  public:
3222   virtual void do_oop(oop* p)       { VerifyFieldClosure::do_oop_work(p); }
3223   virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); }
3224 };
3225 
3226 void InstanceKlass::verify_on(outputStream* st) {
3227 #ifndef PRODUCT
3228   // Avoid redundant verifies, this really should be in product.
3229   if (_verify_count == Universe::verify_count()) return;
3230   _verify_count = Universe::verify_count();
3231 #endif
3232 
3233   // Verify Klass
3234   Klass::verify_on(st);
3235 
3236   // Verify that klass is present in ClassLoaderData
3237   guarantee(class_loader_data()->contains_klass(this),
3238             "this class isn't found in class loader data");
3239 
3240   // Verify vtables
3241   if (is_linked()) {
3242     ResourceMark rm;
3243     // $$$ This used to be done only for m/s collections.  Doing it
3244     // always seemed a valid generalization.  (DLD -- 6/00)
3245     vtable()->verify(st);
3246   }
3247 
3248   // Verify first subklass
3249   if (subklass() != NULL) {
3250     guarantee(subklass()->is_klass(), "should be klass");
3251   }
3252 
3253   // Verify siblings
3254   Klass* super = this->super();
3255   Klass* sib = next_sibling();
3256   if (sib != NULL) {
3257     if (sib == this) {
3258       fatal("subclass points to itself " PTR_FORMAT, p2i(sib));
3259     }
3260 
3261     guarantee(sib->is_klass(), "should be klass");
3262     guarantee(sib->super() == super, "siblings should have same superklass");
3263   }
3264 
3265   // Verify implementor fields
3266   Klass* im = implementor();
3267   if (im != NULL) {
3268     guarantee(is_interface(), "only interfaces should have implementor set");
3269     guarantee(im->is_klass(), "should be klass");
3270     guarantee(!im->is_interface() || im == this,
3271       "implementors cannot be interfaces");
3272   }
3273 
3274   // Verify local interfaces
3275   if (local_interfaces()) {
3276     Array<Klass*>* local_interfaces = this->local_interfaces();
3277     for (int j = 0; j < local_interfaces->length(); j++) {
3278       Klass* e = local_interfaces->at(j);
3279       guarantee(e->is_klass() && e->is_interface(), "invalid local interface");
3280     }
3281   }
3282 
3283   // Verify transitive interfaces
3284   if (transitive_interfaces() != NULL) {
3285     Array<Klass*>* transitive_interfaces = this->transitive_interfaces();
3286     for (int j = 0; j < transitive_interfaces->length(); j++) {
3287       Klass* e = transitive_interfaces->at(j);
3288       guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface");
3289     }
3290   }
3291 
3292   // Verify methods
3293   if (methods() != NULL) {
3294     Array<Method*>* methods = this->methods();
3295     for (int j = 0; j < methods->length(); j++) {
3296       guarantee(methods->at(j)->is_method(), "non-method in methods array");
3297     }
3298     for (int j = 0; j < methods->length() - 1; j++) {
3299       Method* m1 = methods->at(j);
3300       Method* m2 = methods->at(j + 1);
3301       guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3302     }
3303   }
3304 
3305   // Verify method ordering
3306   if (method_ordering() != NULL) {
3307     Array<int>* method_ordering = this->method_ordering();
3308     int length = method_ordering->length();
3309     if (JvmtiExport::can_maintain_original_method_order() ||
3310         ((UseSharedSpaces || DumpSharedSpaces) && length != 0)) {
3311       guarantee(length == methods()->length(), "invalid method ordering length");
3312       jlong sum = 0;
3313       for (int j = 0; j < length; j++) {
3314         int original_index = method_ordering->at(j);
3315         guarantee(original_index >= 0, "invalid method ordering index");
3316         guarantee(original_index < length, "invalid method ordering index");
3317         sum += original_index;
3318       }
3319       // Verify sum of indices 0,1,...,length-1
3320       guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum");
3321     } else {
3322       guarantee(length == 0, "invalid method ordering length");
3323     }
3324   }
3325 
3326   // Verify default methods
3327   if (default_methods() != NULL) {
3328     Array<Method*>* methods = this->default_methods();
3329     for (int j = 0; j < methods->length(); j++) {
3330       guarantee(methods->at(j)->is_method(), "non-method in methods array");
3331     }
3332     for (int j = 0; j < methods->length() - 1; j++) {
3333       Method* m1 = methods->at(j);
3334       Method* m2 = methods->at(j + 1);
3335       guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3336     }
3337   }
3338 
3339   // Verify JNI static field identifiers
3340   if (jni_ids() != NULL) {
3341     jni_ids()->verify(this);
3342   }
3343 
3344   // Verify other fields
3345   if (array_klasses() != NULL) {
3346     guarantee(array_klasses()->is_klass(), "should be klass");
3347   }
3348   if (constants() != NULL) {
3349     guarantee(constants()->is_constantPool(), "should be constant pool");
3350   }
3351   const Klass* host = host_klass();
3352   if (host != NULL) {
3353     guarantee(host->is_klass(), "should be klass");
3354   }
3355 }
3356 
3357 void InstanceKlass::oop_verify_on(oop obj, outputStream* st) {
3358   Klass::oop_verify_on(obj, st);
3359   VerifyFieldClosure blk;
3360   obj->oop_iterate_no_header(&blk);
3361 }
3362 
3363 
3364 // JNIid class for jfieldIDs only
3365 // Note to reviewers:
3366 // These JNI functions are just moved over to column 1 and not changed
3367 // in the compressed oops workspace.
3368 JNIid::JNIid(Klass* holder, int offset, JNIid* next) {
3369   _holder = holder;
3370   _offset = offset;
3371   _next = next;
3372   debug_only(_is_static_field_id = false;)
3373 }
3374 
3375 
3376 JNIid* JNIid::find(int offset) {
3377   JNIid* current = this;
3378   while (current != NULL) {
3379     if (current->offset() == offset) return current;
3380     current = current->next();
3381   }
3382   return NULL;
3383 }
3384 
3385 void JNIid::deallocate(JNIid* current) {
3386   while (current != NULL) {
3387     JNIid* next = current->next();
3388     delete current;
3389     current = next;
3390   }
3391 }
3392 
3393 
3394 void JNIid::verify(Klass* holder) {
3395   int first_field_offset  = InstanceMirrorKlass::offset_of_static_fields();
3396   int end_field_offset;
3397   end_field_offset = first_field_offset + (InstanceKlass::cast(holder)->static_field_size() * wordSize);
3398 
3399   JNIid* current = this;
3400   while (current != NULL) {
3401     guarantee(current->holder() == holder, "Invalid klass in JNIid");
3402 #ifdef ASSERT
3403     int o = current->offset();
3404     if (current->is_static_field_id()) {
3405       guarantee(o >= first_field_offset  && o < end_field_offset,  "Invalid static field offset in JNIid");
3406     }
3407 #endif
3408     current = current->next();
3409   }
3410 }
3411 
3412 
3413 #ifdef ASSERT
3414 void InstanceKlass::set_init_state(ClassState state) {
3415   bool good_state = is_shared() ? (_init_state <= state)
3416                                                : (_init_state < state);
3417   assert(good_state || state == allocated, "illegal state transition");
3418   _init_state = (u1)state;
3419 }
3420 #endif
3421 
3422 #if INCLUDE_JVMTI
3423 
3424 // RedefineClasses() support for previous versions
3425 
3426 // Globally, there is at least one previous version of a class to walk
3427 // during class unloading, which is saved because old methods in the class
3428 // are still running.   Otherwise the previous version list is cleaned up.
3429 bool InstanceKlass::_has_previous_versions = false;
3430 
3431 // Returns true if there are previous versions of a class for class
3432 // unloading only. Also resets the flag to false. purge_previous_version
3433 // will set the flag to true if there are any left, i.e., if there's any
3434 // work to do for next time. This is to avoid the expensive code cache
3435 // walk in CLDG::do_unloading().
3436 bool InstanceKlass::has_previous_versions_and_reset() {
3437   bool ret = _has_previous_versions;
3438   log_trace(redefine, class, iklass, purge)("Class unloading: has_previous_versions = %s",
3439      ret ? "true" : "false");
3440   _has_previous_versions = false;
3441   return ret;
3442 }
3443 
3444 // Purge previous versions before adding new previous versions of the class and
3445 // during class unloading.
3446 void InstanceKlass::purge_previous_version_list() {
3447   assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
3448   assert(has_been_redefined(), "Should only be called for main class");
3449 
3450   // Quick exit.
3451   if (previous_versions() == NULL) {
3452     return;
3453   }
3454 
3455   // This klass has previous versions so see what we can cleanup
3456   // while it is safe to do so.
3457 
3458   int deleted_count = 0;    // leave debugging breadcrumbs
3459   int live_count = 0;
3460   ClassLoaderData* loader_data = class_loader_data();
3461   assert(loader_data != NULL, "should never be null");
3462 
3463   ResourceMark rm;
3464   log_trace(redefine, class, iklass, purge)("%s: previous versions", external_name());
3465 
3466   // previous versions are linked together through the InstanceKlass
3467   InstanceKlass* pv_node = previous_versions();
3468   InstanceKlass* last = this;
3469   int version = 0;
3470 
3471   // check the previous versions list
3472   for (; pv_node != NULL; ) {
3473 
3474     ConstantPool* pvcp = pv_node->constants();
3475     assert(pvcp != NULL, "cp ref was unexpectedly cleared");
3476 
3477     if (!pvcp->on_stack()) {
3478       // If the constant pool isn't on stack, none of the methods
3479       // are executing.  Unlink this previous_version.
3480       // The previous version InstanceKlass is on the ClassLoaderData deallocate list
3481       // so will be deallocated during the next phase of class unloading.
3482       log_trace(redefine, class, iklass, purge)
3483         ("previous version " INTPTR_FORMAT " is dead.", p2i(pv_node));
3484       // For debugging purposes.
3485       pv_node->set_is_scratch_class();
3486       // Unlink from previous version list.
3487       assert(pv_node->class_loader_data() == loader_data, "wrong loader_data");
3488       InstanceKlass* next = pv_node->previous_versions();
3489       pv_node->link_previous_versions(NULL);   // point next to NULL
3490       last->link_previous_versions(next);
3491       // Add to the deallocate list after unlinking
3492       loader_data->add_to_deallocate_list(pv_node);
3493       pv_node = next;
3494       deleted_count++;
3495       version++;
3496       continue;
3497     } else {
3498       log_trace(redefine, class, iklass, purge)("previous version " INTPTR_FORMAT " is alive", p2i(pv_node));
3499       assert(pvcp->pool_holder() != NULL, "Constant pool with no holder");
3500       guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack");
3501       live_count++;
3502       // found a previous version for next time we do class unloading
3503       _has_previous_versions = true;
3504     }
3505 
3506     // At least one method is live in this previous version.
3507     // Reset dead EMCP methods not to get breakpoints.
3508     // All methods are deallocated when all of the methods for this class are no
3509     // longer running.
3510     Array<Method*>* method_refs = pv_node->methods();
3511     if (method_refs != NULL) {
3512       log_trace(redefine, class, iklass, purge)("previous methods length=%d", method_refs->length());
3513       for (int j = 0; j < method_refs->length(); j++) {
3514         Method* method = method_refs->at(j);
3515 
3516         if (!method->on_stack()) {
3517           // no breakpoints for non-running methods
3518           if (method->is_running_emcp()) {
3519             method->set_running_emcp(false);
3520           }
3521         } else {
3522           assert (method->is_obsolete() || method->is_running_emcp(),
3523                   "emcp method cannot run after emcp bit is cleared");
3524           log_trace(redefine, class, iklass, purge)
3525             ("purge: %s(%s): prev method @%d in version @%d is alive",
3526              method->name()->as_C_string(), method->signature()->as_C_string(), j, version);
3527         }
3528       }
3529     }
3530     // next previous version
3531     last = pv_node;
3532     pv_node = pv_node->previous_versions();
3533     version++;
3534   }
3535   log_trace(redefine, class, iklass, purge)
3536     ("previous version stats: live=%d, deleted=%d", live_count, deleted_count);
3537 }
3538 
3539 void InstanceKlass::mark_newly_obsolete_methods(Array<Method*>* old_methods,
3540                                                 int emcp_method_count) {
3541   int obsolete_method_count = old_methods->length() - emcp_method_count;
3542 
3543   if (emcp_method_count != 0 && obsolete_method_count != 0 &&
3544       _previous_versions != NULL) {
3545     // We have a mix of obsolete and EMCP methods so we have to
3546     // clear out any matching EMCP method entries the hard way.
3547     int local_count = 0;
3548     for (int i = 0; i < old_methods->length(); i++) {
3549       Method* old_method = old_methods->at(i);
3550       if (old_method->is_obsolete()) {
3551         // only obsolete methods are interesting
3552         Symbol* m_name = old_method->name();
3553         Symbol* m_signature = old_method->signature();
3554 
3555         // previous versions are linked together through the InstanceKlass
3556         int j = 0;
3557         for (InstanceKlass* prev_version = _previous_versions;
3558              prev_version != NULL;
3559              prev_version = prev_version->previous_versions(), j++) {
3560 
3561           Array<Method*>* method_refs = prev_version->methods();
3562           for (int k = 0; k < method_refs->length(); k++) {
3563             Method* method = method_refs->at(k);
3564 
3565             if (!method->is_obsolete() &&
3566                 method->name() == m_name &&
3567                 method->signature() == m_signature) {
3568               // The current RedefineClasses() call has made all EMCP
3569               // versions of this method obsolete so mark it as obsolete
3570               log_trace(redefine, class, iklass, add)
3571                 ("%s(%s): flush obsolete method @%d in version @%d",
3572                  m_name->as_C_string(), m_signature->as_C_string(), k, j);
3573 
3574               method->set_is_obsolete();
3575               break;
3576             }
3577           }
3578 
3579           // The previous loop may not find a matching EMCP method, but
3580           // that doesn't mean that we can optimize and not go any
3581           // further back in the PreviousVersion generations. The EMCP
3582           // method for this generation could have already been made obsolete,
3583           // but there still may be an older EMCP method that has not
3584           // been made obsolete.
3585         }
3586 
3587         if (++local_count >= obsolete_method_count) {
3588           // no more obsolete methods so bail out now
3589           break;
3590         }
3591       }
3592     }
3593   }
3594 }
3595 
3596 // Save the scratch_class as the previous version if any of the methods are running.
3597 // The previous_versions are used to set breakpoints in EMCP methods and they are
3598 // also used to clean MethodData links to redefined methods that are no longer running.
3599 void InstanceKlass::add_previous_version(InstanceKlass* scratch_class,
3600                                          int emcp_method_count) {
3601   assert(Thread::current()->is_VM_thread(),
3602          "only VMThread can add previous versions");
3603 
3604   ResourceMark rm;
3605   log_trace(redefine, class, iklass, add)
3606     ("adding previous version ref for %s, EMCP_cnt=%d", scratch_class->external_name(), emcp_method_count);
3607 
3608   // Clean out old previous versions for this class
3609   purge_previous_version_list();
3610 
3611   // Mark newly obsolete methods in remaining previous versions.  An EMCP method from
3612   // a previous redefinition may be made obsolete by this redefinition.
3613   Array<Method*>* old_methods = scratch_class->methods();
3614   mark_newly_obsolete_methods(old_methods, emcp_method_count);
3615 
3616   // If the constant pool for this previous version of the class
3617   // is not marked as being on the stack, then none of the methods
3618   // in this previous version of the class are on the stack so
3619   // we don't need to add this as a previous version.
3620   ConstantPool* cp_ref = scratch_class->constants();
3621   if (!cp_ref->on_stack()) {
3622     log_trace(redefine, class, iklass, add)("scratch class not added; no methods are running");
3623     // For debugging purposes.
3624     scratch_class->set_is_scratch_class();
3625     scratch_class->class_loader_data()->add_to_deallocate_list(scratch_class);
3626     return;
3627   }
3628 
3629   if (emcp_method_count != 0) {
3630     // At least one method is still running, check for EMCP methods
3631     for (int i = 0; i < old_methods->length(); i++) {
3632       Method* old_method = old_methods->at(i);
3633       if (!old_method->is_obsolete() && old_method->on_stack()) {
3634         // if EMCP method (not obsolete) is on the stack, mark as EMCP so that
3635         // we can add breakpoints for it.
3636 
3637         // We set the method->on_stack bit during safepoints for class redefinition
3638         // and use this bit to set the is_running_emcp bit.
3639         // After the safepoint, the on_stack bit is cleared and the running emcp
3640         // method may exit.   If so, we would set a breakpoint in a method that
3641         // is never reached, but this won't be noticeable to the programmer.
3642         old_method->set_running_emcp(true);
3643         log_trace(redefine, class, iklass, add)
3644           ("EMCP method %s is on_stack " INTPTR_FORMAT, old_method->name_and_sig_as_C_string(), p2i(old_method));
3645       } else if (!old_method->is_obsolete()) {
3646         log_trace(redefine, class, iklass, add)
3647           ("EMCP method %s is NOT on_stack " INTPTR_FORMAT, old_method->name_and_sig_as_C_string(), p2i(old_method));
3648       }
3649     }
3650   }
3651 
3652   // Add previous version if any methods are still running.
3653   // Set has_previous_version flag for processing during class unloading.
3654   _has_previous_versions = true;
3655   log_trace(redefine, class, iklass, add) ("scratch class added; one of its methods is on_stack.");
3656   assert(scratch_class->previous_versions() == NULL, "shouldn't have a previous version");
3657   scratch_class->link_previous_versions(previous_versions());
3658   link_previous_versions(scratch_class);
3659 } // end add_previous_version()
3660 
3661 #endif // INCLUDE_JVMTI
3662 
3663 Method* InstanceKlass::method_with_idnum(int idnum) {
3664   Method* m = NULL;
3665   if (idnum < methods()->length()) {
3666     m = methods()->at(idnum);
3667   }
3668   if (m == NULL || m->method_idnum() != idnum) {
3669     for (int index = 0; index < methods()->length(); ++index) {
3670       m = methods()->at(index);
3671       if (m->method_idnum() == idnum) {
3672         return m;
3673       }
3674     }
3675     // None found, return null for the caller to handle.
3676     return NULL;
3677   }
3678   return m;
3679 }
3680 
3681 
3682 Method* InstanceKlass::method_with_orig_idnum(int idnum) {
3683   if (idnum >= methods()->length()) {
3684     return NULL;
3685   }
3686   Method* m = methods()->at(idnum);
3687   if (m != NULL && m->orig_method_idnum() == idnum) {
3688     return m;
3689   }
3690   // Obsolete method idnum does not match the original idnum
3691   for (int index = 0; index < methods()->length(); ++index) {
3692     m = methods()->at(index);
3693     if (m->orig_method_idnum() == idnum) {
3694       return m;
3695     }
3696   }
3697   // None found, return null for the caller to handle.
3698   return NULL;
3699 }
3700 
3701 
3702 Method* InstanceKlass::method_with_orig_idnum(int idnum, int version) {
3703   InstanceKlass* holder = get_klass_version(version);
3704   if (holder == NULL) {
3705     return NULL; // The version of klass is gone, no method is found
3706   }
3707   Method* method = holder->method_with_orig_idnum(idnum);
3708   return method;
3709 }
3710 
3711 #if INCLUDE_JVMTI
3712 JvmtiCachedClassFileData* InstanceKlass::get_cached_class_file() {
3713   if (MetaspaceShared::is_in_shared_space(_cached_class_file)) {
3714     // Ignore the archived class stream data
3715     return NULL;
3716   } else {
3717     return _cached_class_file;
3718   }
3719 }
3720 
3721 jint InstanceKlass::get_cached_class_file_len() {
3722   return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file);
3723 }
3724 
3725 unsigned char * InstanceKlass::get_cached_class_file_bytes() {
3726   return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file);
3727 }
3728 
3729 #if INCLUDE_CDS
3730 JvmtiCachedClassFileData* InstanceKlass::get_archived_class_data() {
3731   assert(this->is_shared(), "class should be shared");
3732   if (MetaspaceShared::is_in_shared_space(_cached_class_file)) {
3733     return _cached_class_file;
3734   } else {
3735     return NULL;
3736   }
3737 }
3738 #endif
3739 #endif
--- EOF ---