src/share/vm/oops/instanceKlass.cpp

Fri, 08 Jan 2010 13:47:01 -0800

author
jrose
date
Fri, 08 Jan 2010 13:47:01 -0800
changeset 1590
4e6abf09f540
parent 1579
9b9c1ee9b3f6
child 1759
e392695de029
permissions
-rw-r--r--

6912062: disassembler plugin needs to produce symbolic information in product mode
Summary: More informative disassembly in product mode. Also, a more consistent CompileCommand syntax.
Reviewed-by: never

     1 /*
     2  * Copyright 1997-2009 Sun Microsystems, Inc.  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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
    20  * CA 95054 USA or visit www.sun.com if you need additional information or
    21  * have any questions.
    22  *
    23  */
    25 # include "incls/_precompiled.incl"
    26 # include "incls/_instanceKlass.cpp.incl"
    28 bool instanceKlass::should_be_initialized() const {
    29   return !is_initialized();
    30 }
    32 klassVtable* instanceKlass::vtable() const {
    33   return new klassVtable(as_klassOop(), start_of_vtable(), vtable_length() / vtableEntry::size());
    34 }
    36 klassItable* instanceKlass::itable() const {
    37   return new klassItable(as_klassOop());
    38 }
    40 void instanceKlass::eager_initialize(Thread *thread) {
    41   if (!EagerInitialization) return;
    43   if (this->is_not_initialized()) {
    44     // abort if the the class has a class initializer
    45     if (this->class_initializer() != NULL) return;
    47     // abort if it is java.lang.Object (initialization is handled in genesis)
    48     klassOop super = this->super();
    49     if (super == NULL) return;
    51     // abort if the super class should be initialized
    52     if (!instanceKlass::cast(super)->is_initialized()) return;
    54     // call body to expose the this pointer
    55     instanceKlassHandle this_oop(thread, this->as_klassOop());
    56     eager_initialize_impl(this_oop);
    57   }
    58 }
    61 void instanceKlass::eager_initialize_impl(instanceKlassHandle this_oop) {
    62   EXCEPTION_MARK;
    63   ObjectLocker ol(this_oop, THREAD);
    65   // abort if someone beat us to the initialization
    66   if (!this_oop->is_not_initialized()) return;  // note: not equivalent to is_initialized()
    68   ClassState old_state = this_oop->_init_state;
    69   link_class_impl(this_oop, true, THREAD);
    70   if (HAS_PENDING_EXCEPTION) {
    71     CLEAR_PENDING_EXCEPTION;
    72     // Abort if linking the class throws an exception.
    74     // Use a test to avoid redundantly resetting the state if there's
    75     // no change.  Set_init_state() asserts that state changes make
    76     // progress, whereas here we might just be spinning in place.
    77     if( old_state != this_oop->_init_state )
    78       this_oop->set_init_state (old_state);
    79   } else {
    80     // linking successfull, mark class as initialized
    81     this_oop->set_init_state (fully_initialized);
    82     // trace
    83     if (TraceClassInitialization) {
    84       ResourceMark rm(THREAD);
    85       tty->print_cr("[Initialized %s without side effects]", this_oop->external_name());
    86     }
    87   }
    88 }
    91 // See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization
    92 // process. The step comments refers to the procedure described in that section.
    93 // Note: implementation moved to static method to expose the this pointer.
    94 void instanceKlass::initialize(TRAPS) {
    95   if (this->should_be_initialized()) {
    96     HandleMark hm(THREAD);
    97     instanceKlassHandle this_oop(THREAD, this->as_klassOop());
    98     initialize_impl(this_oop, CHECK);
    99     // Note: at this point the class may be initialized
   100     //       OR it may be in the state of being initialized
   101     //       in case of recursive initialization!
   102   } else {
   103     assert(is_initialized(), "sanity check");
   104   }
   105 }
   108 bool instanceKlass::verify_code(
   109     instanceKlassHandle this_oop, bool throw_verifyerror, TRAPS) {
   110   // 1) Verify the bytecodes
   111   Verifier::Mode mode =
   112     throw_verifyerror ? Verifier::ThrowException : Verifier::NoException;
   113   return Verifier::verify(this_oop, mode, this_oop->should_verify_class(), CHECK_false);
   114 }
   117 // Used exclusively by the shared spaces dump mechanism to prevent
   118 // classes mapped into the shared regions in new VMs from appearing linked.
   120 void instanceKlass::unlink_class() {
   121   assert(is_linked(), "must be linked");
   122   _init_state = loaded;
   123 }
   125 void instanceKlass::link_class(TRAPS) {
   126   assert(is_loaded(), "must be loaded");
   127   if (!is_linked()) {
   128     instanceKlassHandle this_oop(THREAD, this->as_klassOop());
   129     link_class_impl(this_oop, true, CHECK);
   130   }
   131 }
   133 // Called to verify that a class can link during initialization, without
   134 // throwing a VerifyError.
   135 bool instanceKlass::link_class_or_fail(TRAPS) {
   136   assert(is_loaded(), "must be loaded");
   137   if (!is_linked()) {
   138     instanceKlassHandle this_oop(THREAD, this->as_klassOop());
   139     link_class_impl(this_oop, false, CHECK_false);
   140   }
   141   return is_linked();
   142 }
   144 bool instanceKlass::link_class_impl(
   145     instanceKlassHandle this_oop, bool throw_verifyerror, TRAPS) {
   146   // check for error state
   147   if (this_oop->is_in_error_state()) {
   148     ResourceMark rm(THREAD);
   149     THROW_MSG_(vmSymbols::java_lang_NoClassDefFoundError(),
   150                this_oop->external_name(), false);
   151   }
   152   // return if already verified
   153   if (this_oop->is_linked()) {
   154     return true;
   155   }
   157   // Timing
   158   // timer handles recursion
   159   assert(THREAD->is_Java_thread(), "non-JavaThread in link_class_impl");
   160   JavaThread* jt = (JavaThread*)THREAD;
   162   // link super class before linking this class
   163   instanceKlassHandle super(THREAD, this_oop->super());
   164   if (super.not_null()) {
   165     if (super->is_interface()) {  // check if super class is an interface
   166       ResourceMark rm(THREAD);
   167       Exceptions::fthrow(
   168         THREAD_AND_LOCATION,
   169         vmSymbolHandles::java_lang_IncompatibleClassChangeError(),
   170         "class %s has interface %s as super class",
   171         this_oop->external_name(),
   172         super->external_name()
   173       );
   174       return false;
   175     }
   177     link_class_impl(super, throw_verifyerror, CHECK_false);
   178   }
   180   // link all interfaces implemented by this class before linking this class
   181   objArrayHandle interfaces (THREAD, this_oop->local_interfaces());
   182   int num_interfaces = interfaces->length();
   183   for (int index = 0; index < num_interfaces; index++) {
   184     HandleMark hm(THREAD);
   185     instanceKlassHandle ih(THREAD, klassOop(interfaces->obj_at(index)));
   186     link_class_impl(ih, throw_verifyerror, CHECK_false);
   187   }
   189   // in case the class is linked in the process of linking its superclasses
   190   if (this_oop->is_linked()) {
   191     return true;
   192   }
   194   // trace only the link time for this klass that includes
   195   // the verification time
   196   PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(),
   197                              ClassLoader::perf_class_link_selftime(),
   198                              ClassLoader::perf_classes_linked(),
   199                              jt->get_thread_stat()->perf_recursion_counts_addr(),
   200                              jt->get_thread_stat()->perf_timers_addr(),
   201                              PerfClassTraceTime::CLASS_LINK);
   203   // verification & rewriting
   204   {
   205     ObjectLocker ol(this_oop, THREAD);
   206     // rewritten will have been set if loader constraint error found
   207     // on an earlier link attempt
   208     // don't verify or rewrite if already rewritten
   209     if (!this_oop->is_linked()) {
   210       if (!this_oop->is_rewritten()) {
   211         {
   212           // Timer includes any side effects of class verification (resolution,
   213           // etc), but not recursive entry into verify_code().
   214           PerfClassTraceTime timer(ClassLoader::perf_class_verify_time(),
   215                                    ClassLoader::perf_class_verify_selftime(),
   216                                    ClassLoader::perf_classes_verified(),
   217                                    jt->get_thread_stat()->perf_recursion_counts_addr(),
   218                                    jt->get_thread_stat()->perf_timers_addr(),
   219                                    PerfClassTraceTime::CLASS_VERIFY);
   220           bool verify_ok = verify_code(this_oop, throw_verifyerror, THREAD);
   221           if (!verify_ok) {
   222             return false;
   223           }
   224         }
   226         // Just in case a side-effect of verify linked this class already
   227         // (which can sometimes happen since the verifier loads classes
   228         // using custom class loaders, which are free to initialize things)
   229         if (this_oop->is_linked()) {
   230           return true;
   231         }
   233         // also sets rewritten
   234         this_oop->rewrite_class(CHECK_false);
   235       }
   237       // Initialize the vtable and interface table after
   238       // methods have been rewritten since rewrite may
   239       // fabricate new methodOops.
   240       // also does loader constraint checking
   241       if (!this_oop()->is_shared()) {
   242         ResourceMark rm(THREAD);
   243         this_oop->vtable()->initialize_vtable(true, CHECK_false);
   244         this_oop->itable()->initialize_itable(true, CHECK_false);
   245       }
   246 #ifdef ASSERT
   247       else {
   248         ResourceMark rm(THREAD);
   249         this_oop->vtable()->verify(tty, true);
   250         // In case itable verification is ever added.
   251         // this_oop->itable()->verify(tty, true);
   252       }
   253 #endif
   254       this_oop->set_init_state(linked);
   255       if (JvmtiExport::should_post_class_prepare()) {
   256         Thread *thread = THREAD;
   257         assert(thread->is_Java_thread(), "thread->is_Java_thread()");
   258         JvmtiExport::post_class_prepare((JavaThread *) thread, this_oop());
   259       }
   260     }
   261   }
   262   return true;
   263 }
   266 // Rewrite the byte codes of all of the methods of a class.
   267 // Three cases:
   268 //    During the link of a newly loaded class.
   269 //    During the preloading of classes to be written to the shared spaces.
   270 //      - Rewrite the methods and update the method entry points.
   271 //
   272 //    During the link of a class in the shared spaces.
   273 //      - The methods were already rewritten, update the metho entry points.
   274 //
   275 // The rewriter must be called exactly once. Rewriting must happen after
   276 // verification but before the first method of the class is executed.
   278 void instanceKlass::rewrite_class(TRAPS) {
   279   assert(is_loaded(), "must be loaded");
   280   instanceKlassHandle this_oop(THREAD, this->as_klassOop());
   281   if (this_oop->is_rewritten()) {
   282     assert(this_oop()->is_shared(), "rewriting an unshared class?");
   283     return;
   284   }
   285   Rewriter::rewrite(this_oop, CHECK); // No exception can happen here
   286   this_oop->set_rewritten();
   287 }
   290 void instanceKlass::initialize_impl(instanceKlassHandle this_oop, TRAPS) {
   291   // Make sure klass is linked (verified) before initialization
   292   // A class could already be verified, since it has been reflected upon.
   293   this_oop->link_class(CHECK);
   295   // refer to the JVM book page 47 for description of steps
   296   // Step 1
   297   { ObjectLocker ol(this_oop, THREAD);
   299     Thread *self = THREAD; // it's passed the current thread
   301     // Step 2
   302     // If we were to use wait() instead of waitInterruptibly() then
   303     // we might end up throwing IE from link/symbol resolution sites
   304     // that aren't expected to throw.  This would wreak havoc.  See 6320309.
   305     while(this_oop->is_being_initialized() && !this_oop->is_reentrant_initialization(self)) {
   306       ol.waitUninterruptibly(CHECK);
   307     }
   309     // Step 3
   310     if (this_oop->is_being_initialized() && this_oop->is_reentrant_initialization(self))
   311       return;
   313     // Step 4
   314     if (this_oop->is_initialized())
   315       return;
   317     // Step 5
   318     if (this_oop->is_in_error_state()) {
   319       ResourceMark rm(THREAD);
   320       const char* desc = "Could not initialize class ";
   321       const char* className = this_oop->external_name();
   322       size_t msglen = strlen(desc) + strlen(className) + 1;
   323       char* message = NEW_C_HEAP_ARRAY(char, msglen);
   324       if (NULL == message) {
   325         // Out of memory: can't create detailed error message
   326         THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), className);
   327       } else {
   328         jio_snprintf(message, msglen, "%s%s", desc, className);
   329         THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), message);
   330       }
   331     }
   333     // Step 6
   334     this_oop->set_init_state(being_initialized);
   335     this_oop->set_init_thread(self);
   336   }
   338   // Step 7
   339   klassOop super_klass = this_oop->super();
   340   if (super_klass != NULL && !this_oop->is_interface() && Klass::cast(super_klass)->should_be_initialized()) {
   341     Klass::cast(super_klass)->initialize(THREAD);
   343     if (HAS_PENDING_EXCEPTION) {
   344       Handle e(THREAD, PENDING_EXCEPTION);
   345       CLEAR_PENDING_EXCEPTION;
   346       {
   347         EXCEPTION_MARK;
   348         this_oop->set_initialization_state_and_notify(initialization_error, THREAD); // Locks object, set state, and notify all waiting threads
   349         CLEAR_PENDING_EXCEPTION;   // ignore any exception thrown, superclass initialization error is thrown below
   350       }
   351       THROW_OOP(e());
   352     }
   353   }
   355   // Step 8
   356   {
   357     assert(THREAD->is_Java_thread(), "non-JavaThread in initialize_impl");
   358     JavaThread* jt = (JavaThread*)THREAD;
   359     // Timer includes any side effects of class initialization (resolution,
   360     // etc), but not recursive entry into call_class_initializer().
   361     PerfClassTraceTime timer(ClassLoader::perf_class_init_time(),
   362                              ClassLoader::perf_class_init_selftime(),
   363                              ClassLoader::perf_classes_inited(),
   364                              jt->get_thread_stat()->perf_recursion_counts_addr(),
   365                              jt->get_thread_stat()->perf_timers_addr(),
   366                              PerfClassTraceTime::CLASS_CLINIT);
   367     this_oop->call_class_initializer(THREAD);
   368   }
   370   // Step 9
   371   if (!HAS_PENDING_EXCEPTION) {
   372     this_oop->set_initialization_state_and_notify(fully_initialized, CHECK);
   373     { ResourceMark rm(THREAD);
   374       debug_only(this_oop->vtable()->verify(tty, true);)
   375     }
   376   }
   377   else {
   378     // Step 10 and 11
   379     Handle e(THREAD, PENDING_EXCEPTION);
   380     CLEAR_PENDING_EXCEPTION;
   381     {
   382       EXCEPTION_MARK;
   383       this_oop->set_initialization_state_and_notify(initialization_error, THREAD);
   384       CLEAR_PENDING_EXCEPTION;   // ignore any exception thrown, class initialization error is thrown below
   385     }
   386     if (e->is_a(SystemDictionary::Error_klass())) {
   387       THROW_OOP(e());
   388     } else {
   389       JavaCallArguments args(e);
   390       THROW_ARG(vmSymbolHandles::java_lang_ExceptionInInitializerError(),
   391                 vmSymbolHandles::throwable_void_signature(),
   392                 &args);
   393     }
   394   }
   395 }
   398 // Note: implementation moved to static method to expose the this pointer.
   399 void instanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) {
   400   instanceKlassHandle kh(THREAD, this->as_klassOop());
   401   set_initialization_state_and_notify_impl(kh, state, CHECK);
   402 }
   404 void instanceKlass::set_initialization_state_and_notify_impl(instanceKlassHandle this_oop, ClassState state, TRAPS) {
   405   ObjectLocker ol(this_oop, THREAD);
   406   this_oop->set_init_state(state);
   407   ol.notify_all(CHECK);
   408 }
   410 void instanceKlass::add_implementor(klassOop k) {
   411   assert(Compile_lock->owned_by_self(), "");
   412   // Filter out my subinterfaces.
   413   // (Note: Interfaces are never on the subklass list.)
   414   if (instanceKlass::cast(k)->is_interface()) return;
   416   // Filter out subclasses whose supers already implement me.
   417   // (Note: CHA must walk subclasses of direct implementors
   418   // in order to locate indirect implementors.)
   419   klassOop sk = instanceKlass::cast(k)->super();
   420   if (sk != NULL && instanceKlass::cast(sk)->implements_interface(as_klassOop()))
   421     // We only need to check one immediate superclass, since the
   422     // implements_interface query looks at transitive_interfaces.
   423     // Any supers of the super have the same (or fewer) transitive_interfaces.
   424     return;
   426   // Update number of implementors
   427   int i = _nof_implementors++;
   429   // Record this implementor, if there are not too many already
   430   if (i < implementors_limit) {
   431     assert(_implementors[i] == NULL, "should be exactly one implementor");
   432     oop_store_without_check((oop*)&_implementors[i], k);
   433   } else if (i == implementors_limit) {
   434     // clear out the list on first overflow
   435     for (int i2 = 0; i2 < implementors_limit; i2++)
   436       oop_store_without_check((oop*)&_implementors[i2], NULL);
   437   }
   439   // The implementor also implements the transitive_interfaces
   440   for (int index = 0; index < local_interfaces()->length(); index++) {
   441     instanceKlass::cast(klassOop(local_interfaces()->obj_at(index)))->add_implementor(k);
   442   }
   443 }
   445 void instanceKlass::init_implementor() {
   446   for (int i = 0; i < implementors_limit; i++)
   447     oop_store_without_check((oop*)&_implementors[i], NULL);
   448   _nof_implementors = 0;
   449 }
   452 void instanceKlass::process_interfaces(Thread *thread) {
   453   // link this class into the implementors list of every interface it implements
   454   KlassHandle this_as_oop (thread, this->as_klassOop());
   455   for (int i = local_interfaces()->length() - 1; i >= 0; i--) {
   456     assert(local_interfaces()->obj_at(i)->is_klass(), "must be a klass");
   457     instanceKlass* interf = instanceKlass::cast(klassOop(local_interfaces()->obj_at(i)));
   458     assert(interf->is_interface(), "expected interface");
   459     interf->add_implementor(this_as_oop());
   460   }
   461 }
   463 bool instanceKlass::can_be_primary_super_slow() const {
   464   if (is_interface())
   465     return false;
   466   else
   467     return Klass::can_be_primary_super_slow();
   468 }
   470 objArrayOop instanceKlass::compute_secondary_supers(int num_extra_slots, TRAPS) {
   471   // The secondaries are the implemented interfaces.
   472   instanceKlass* ik = instanceKlass::cast(as_klassOop());
   473   objArrayHandle interfaces (THREAD, ik->transitive_interfaces());
   474   int num_secondaries = num_extra_slots + interfaces->length();
   475   if (num_secondaries == 0) {
   476     return Universe::the_empty_system_obj_array();
   477   } else if (num_extra_slots == 0) {
   478     return interfaces();
   479   } else {
   480     // a mix of both
   481     objArrayOop secondaries = oopFactory::new_system_objArray(num_secondaries, CHECK_NULL);
   482     for (int i = 0; i < interfaces->length(); i++) {
   483       secondaries->obj_at_put(num_extra_slots+i, interfaces->obj_at(i));
   484     }
   485     return secondaries;
   486   }
   487 }
   489 bool instanceKlass::compute_is_subtype_of(klassOop k) {
   490   if (Klass::cast(k)->is_interface()) {
   491     return implements_interface(k);
   492   } else {
   493     return Klass::compute_is_subtype_of(k);
   494   }
   495 }
   497 bool instanceKlass::implements_interface(klassOop k) const {
   498   if (as_klassOop() == k) return true;
   499   assert(Klass::cast(k)->is_interface(), "should be an interface class");
   500   for (int i = 0; i < transitive_interfaces()->length(); i++) {
   501     if (transitive_interfaces()->obj_at(i) == k) {
   502       return true;
   503     }
   504   }
   505   return false;
   506 }
   508 objArrayOop instanceKlass::allocate_objArray(int n, int length, TRAPS) {
   509   if (length < 0) THROW_0(vmSymbols::java_lang_NegativeArraySizeException());
   510   if (length > arrayOopDesc::max_array_length(T_OBJECT)) {
   511     report_java_out_of_memory("Requested array size exceeds VM limit");
   512     THROW_OOP_0(Universe::out_of_memory_error_array_size());
   513   }
   514   int size = objArrayOopDesc::object_size(length);
   515   klassOop ak = array_klass(n, CHECK_NULL);
   516   KlassHandle h_ak (THREAD, ak);
   517   objArrayOop o =
   518     (objArrayOop)CollectedHeap::array_allocate(h_ak, size, length, CHECK_NULL);
   519   return o;
   520 }
   522 instanceOop instanceKlass::register_finalizer(instanceOop i, TRAPS) {
   523   if (TraceFinalizerRegistration) {
   524     tty->print("Registered ");
   525     i->print_value_on(tty);
   526     tty->print_cr(" (" INTPTR_FORMAT ") as finalizable", (address)i);
   527   }
   528   instanceHandle h_i(THREAD, i);
   529   // Pass the handle as argument, JavaCalls::call expects oop as jobjects
   530   JavaValue result(T_VOID);
   531   JavaCallArguments args(h_i);
   532   methodHandle mh (THREAD, Universe::finalizer_register_method());
   533   JavaCalls::call(&result, mh, &args, CHECK_NULL);
   534   return h_i();
   535 }
   537 instanceOop instanceKlass::allocate_instance(TRAPS) {
   538   bool has_finalizer_flag = has_finalizer(); // Query before possible GC
   539   int size = size_helper();  // Query before forming handle.
   541   KlassHandle h_k(THREAD, as_klassOop());
   543   instanceOop i;
   545   i = (instanceOop)CollectedHeap::obj_allocate(h_k, size, CHECK_NULL);
   546   if (has_finalizer_flag && !RegisterFinalizersAtInit) {
   547     i = register_finalizer(i, CHECK_NULL);
   548   }
   549   return i;
   550 }
   552 instanceOop instanceKlass::allocate_permanent_instance(TRAPS) {
   553   // Finalizer registration occurs in the Object.<init> constructor
   554   // and constructors normally aren't run when allocating perm
   555   // instances so simply disallow finalizable perm objects.  This can
   556   // be relaxed if a need for it is found.
   557   assert(!has_finalizer(), "perm objects not allowed to have finalizers");
   558   int size = size_helper();  // Query before forming handle.
   559   KlassHandle h_k(THREAD, as_klassOop());
   560   instanceOop i = (instanceOop)
   561     CollectedHeap::permanent_obj_allocate(h_k, size, CHECK_NULL);
   562   return i;
   563 }
   565 void instanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) {
   566   if (is_interface() || is_abstract()) {
   567     ResourceMark rm(THREAD);
   568     THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
   569               : vmSymbols::java_lang_InstantiationException(), external_name());
   570   }
   571   if (as_klassOop() == SystemDictionary::Class_klass()) {
   572     ResourceMark rm(THREAD);
   573     THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError()
   574               : vmSymbols::java_lang_IllegalAccessException(), external_name());
   575   }
   576 }
   578 klassOop instanceKlass::array_klass_impl(bool or_null, int n, TRAPS) {
   579   instanceKlassHandle this_oop(THREAD, as_klassOop());
   580   return array_klass_impl(this_oop, or_null, n, THREAD);
   581 }
   583 klassOop instanceKlass::array_klass_impl(instanceKlassHandle this_oop, bool or_null, int n, TRAPS) {
   584   if (this_oop->array_klasses() == NULL) {
   585     if (or_null) return NULL;
   587     ResourceMark rm;
   588     JavaThread *jt = (JavaThread *)THREAD;
   589     {
   590       // Atomic creation of array_klasses
   591       MutexLocker mc(Compile_lock, THREAD);   // for vtables
   592       MutexLocker ma(MultiArray_lock, THREAD);
   594       // Check if update has already taken place
   595       if (this_oop->array_klasses() == NULL) {
   596         objArrayKlassKlass* oakk =
   597           (objArrayKlassKlass*)Universe::objArrayKlassKlassObj()->klass_part();
   599         klassOop  k = oakk->allocate_objArray_klass(1, this_oop, CHECK_NULL);
   600         this_oop->set_array_klasses(k);
   601       }
   602     }
   603   }
   604   // _this will always be set at this point
   605   objArrayKlass* oak = (objArrayKlass*)this_oop->array_klasses()->klass_part();
   606   if (or_null) {
   607     return oak->array_klass_or_null(n);
   608   }
   609   return oak->array_klass(n, CHECK_NULL);
   610 }
   612 klassOop instanceKlass::array_klass_impl(bool or_null, TRAPS) {
   613   return array_klass_impl(or_null, 1, THREAD);
   614 }
   616 void instanceKlass::call_class_initializer(TRAPS) {
   617   instanceKlassHandle ik (THREAD, as_klassOop());
   618   call_class_initializer_impl(ik, THREAD);
   619 }
   621 static int call_class_initializer_impl_counter = 0;   // for debugging
   623 methodOop instanceKlass::class_initializer() {
   624   return find_method(vmSymbols::class_initializer_name(), vmSymbols::void_method_signature());
   625 }
   627 void instanceKlass::call_class_initializer_impl(instanceKlassHandle this_oop, TRAPS) {
   628   methodHandle h_method(THREAD, this_oop->class_initializer());
   629   assert(!this_oop->is_initialized(), "we cannot initialize twice");
   630   if (TraceClassInitialization) {
   631     tty->print("%d Initializing ", call_class_initializer_impl_counter++);
   632     this_oop->name()->print_value();
   633     tty->print_cr("%s (" INTPTR_FORMAT ")", h_method() == NULL ? "(no method)" : "", (address)this_oop());
   634   }
   635   if (h_method() != NULL) {
   636     JavaCallArguments args; // No arguments
   637     JavaValue result(T_VOID);
   638     JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args)
   639   }
   640 }
   643 void instanceKlass::mask_for(methodHandle method, int bci,
   644   InterpreterOopMap* entry_for) {
   645   // Dirty read, then double-check under a lock.
   646   if (_oop_map_cache == NULL) {
   647     // Otherwise, allocate a new one.
   648     MutexLocker x(OopMapCacheAlloc_lock);
   649     // First time use. Allocate a cache in C heap
   650     if (_oop_map_cache == NULL) {
   651       _oop_map_cache = new OopMapCache();
   652     }
   653   }
   654   // _oop_map_cache is constant after init; lookup below does is own locking.
   655   _oop_map_cache->lookup(method, bci, entry_for);
   656 }
   659 bool instanceKlass::find_local_field(symbolOop name, symbolOop sig, fieldDescriptor* fd) const {
   660   const int n = fields()->length();
   661   for (int i = 0; i < n; i += next_offset ) {
   662     int name_index = fields()->ushort_at(i + name_index_offset);
   663     int sig_index  = fields()->ushort_at(i + signature_index_offset);
   664     symbolOop f_name = constants()->symbol_at(name_index);
   665     symbolOop f_sig  = constants()->symbol_at(sig_index);
   666     if (f_name == name && f_sig == sig) {
   667       fd->initialize(as_klassOop(), i);
   668       return true;
   669     }
   670   }
   671   return false;
   672 }
   675 void instanceKlass::field_names_and_sigs_iterate(OopClosure* closure) {
   676   const int n = fields()->length();
   677   for (int i = 0; i < n; i += next_offset ) {
   678     int name_index = fields()->ushort_at(i + name_index_offset);
   679     symbolOop name = constants()->symbol_at(name_index);
   680     closure->do_oop((oop*)&name);
   682     int sig_index  = fields()->ushort_at(i + signature_index_offset);
   683     symbolOop sig = constants()->symbol_at(sig_index);
   684     closure->do_oop((oop*)&sig);
   685   }
   686 }
   689 klassOop instanceKlass::find_interface_field(symbolOop name, symbolOop sig, fieldDescriptor* fd) const {
   690   const int n = local_interfaces()->length();
   691   for (int i = 0; i < n; i++) {
   692     klassOop intf1 = klassOop(local_interfaces()->obj_at(i));
   693     assert(Klass::cast(intf1)->is_interface(), "just checking type");
   694     // search for field in current interface
   695     if (instanceKlass::cast(intf1)->find_local_field(name, sig, fd)) {
   696       assert(fd->is_static(), "interface field must be static");
   697       return intf1;
   698     }
   699     // search for field in direct superinterfaces
   700     klassOop intf2 = instanceKlass::cast(intf1)->find_interface_field(name, sig, fd);
   701     if (intf2 != NULL) return intf2;
   702   }
   703   // otherwise field lookup fails
   704   return NULL;
   705 }
   708 klassOop instanceKlass::find_field(symbolOop name, symbolOop sig, fieldDescriptor* fd) const {
   709   // search order according to newest JVM spec (5.4.3.2, p.167).
   710   // 1) search for field in current klass
   711   if (find_local_field(name, sig, fd)) {
   712     return as_klassOop();
   713   }
   714   // 2) search for field recursively in direct superinterfaces
   715   { klassOop intf = find_interface_field(name, sig, fd);
   716     if (intf != NULL) return intf;
   717   }
   718   // 3) apply field lookup recursively if superclass exists
   719   { klassOop supr = super();
   720     if (supr != NULL) return instanceKlass::cast(supr)->find_field(name, sig, fd);
   721   }
   722   // 4) otherwise field lookup fails
   723   return NULL;
   724 }
   727 klassOop instanceKlass::find_field(symbolOop name, symbolOop sig, bool is_static, fieldDescriptor* fd) const {
   728   // search order according to newest JVM spec (5.4.3.2, p.167).
   729   // 1) search for field in current klass
   730   if (find_local_field(name, sig, fd)) {
   731     if (fd->is_static() == is_static) return as_klassOop();
   732   }
   733   // 2) search for field recursively in direct superinterfaces
   734   if (is_static) {
   735     klassOop intf = find_interface_field(name, sig, fd);
   736     if (intf != NULL) return intf;
   737   }
   738   // 3) apply field lookup recursively if superclass exists
   739   { klassOop supr = super();
   740     if (supr != NULL) return instanceKlass::cast(supr)->find_field(name, sig, is_static, fd);
   741   }
   742   // 4) otherwise field lookup fails
   743   return NULL;
   744 }
   747 bool instanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
   748   int length = fields()->length();
   749   for (int i = 0; i < length; i += next_offset) {
   750     if (offset_from_fields( i ) == offset) {
   751       fd->initialize(as_klassOop(), i);
   752       if (fd->is_static() == is_static) return true;
   753     }
   754   }
   755   return false;
   756 }
   759 bool instanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
   760   klassOop klass = as_klassOop();
   761   while (klass != NULL) {
   762     if (instanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) {
   763       return true;
   764     }
   765     klass = Klass::cast(klass)->super();
   766   }
   767   return false;
   768 }
   771 void instanceKlass::methods_do(void f(methodOop method)) {
   772   int len = methods()->length();
   773   for (int index = 0; index < len; index++) {
   774     methodOop m = methodOop(methods()->obj_at(index));
   775     assert(m->is_method(), "must be method");
   776     f(m);
   777   }
   778 }
   780 void instanceKlass::do_local_static_fields(FieldClosure* cl) {
   781   fieldDescriptor fd;
   782   int length = fields()->length();
   783   for (int i = 0; i < length; i += next_offset) {
   784     fd.initialize(as_klassOop(), i);
   785     if (fd.is_static()) cl->do_field(&fd);
   786   }
   787 }
   790 void instanceKlass::do_local_static_fields(void f(fieldDescriptor*, TRAPS), TRAPS) {
   791   instanceKlassHandle h_this(THREAD, as_klassOop());
   792   do_local_static_fields_impl(h_this, f, CHECK);
   793 }
   796 void instanceKlass::do_local_static_fields_impl(instanceKlassHandle this_oop, void f(fieldDescriptor* fd, TRAPS), TRAPS) {
   797   fieldDescriptor fd;
   798   int length = this_oop->fields()->length();
   799   for (int i = 0; i < length; i += next_offset) {
   800     fd.initialize(this_oop(), i);
   801     if (fd.is_static()) { f(&fd, CHECK); } // Do NOT remove {}! (CHECK macro expands into several statements)
   802   }
   803 }
   806 static int compare_fields_by_offset(int* a, int* b) {
   807   return a[0] - b[0];
   808 }
   810 void instanceKlass::do_nonstatic_fields(FieldClosure* cl) {
   811   instanceKlass* super = superklass();
   812   if (super != NULL) {
   813     super->do_nonstatic_fields(cl);
   814   }
   815   fieldDescriptor fd;
   816   int length = fields()->length();
   817   // In DebugInfo nonstatic fields are sorted by offset.
   818   int* fields_sorted = NEW_C_HEAP_ARRAY(int, 2*(length+1));
   819   int j = 0;
   820   for (int i = 0; i < length; i += next_offset) {
   821     fd.initialize(as_klassOop(), i);
   822     if (!fd.is_static()) {
   823       fields_sorted[j + 0] = fd.offset();
   824       fields_sorted[j + 1] = i;
   825       j += 2;
   826     }
   827   }
   828   if (j > 0) {
   829     length = j;
   830     // _sort_Fn is defined in growableArray.hpp.
   831     qsort(fields_sorted, length/2, 2*sizeof(int), (_sort_Fn)compare_fields_by_offset);
   832     for (int i = 0; i < length; i += 2) {
   833       fd.initialize(as_klassOop(), fields_sorted[i + 1]);
   834       assert(!fd.is_static() && fd.offset() == fields_sorted[i], "only nonstatic fields");
   835       cl->do_field(&fd);
   836     }
   837   }
   838   FREE_C_HEAP_ARRAY(int, fields_sorted);
   839 }
   842 void instanceKlass::array_klasses_do(void f(klassOop k)) {
   843   if (array_klasses() != NULL)
   844     arrayKlass::cast(array_klasses())->array_klasses_do(f);
   845 }
   848 void instanceKlass::with_array_klasses_do(void f(klassOop k)) {
   849   f(as_klassOop());
   850   array_klasses_do(f);
   851 }
   853 #ifdef ASSERT
   854 static int linear_search(objArrayOop methods, symbolOop name, symbolOop signature) {
   855   int len = methods->length();
   856   for (int index = 0; index < len; index++) {
   857     methodOop m = (methodOop)(methods->obj_at(index));
   858     assert(m->is_method(), "must be method");
   859     if (m->signature() == signature && m->name() == name) {
   860        return index;
   861     }
   862   }
   863   return -1;
   864 }
   865 #endif
   867 methodOop instanceKlass::find_method(symbolOop name, symbolOop signature) const {
   868   return instanceKlass::find_method(methods(), name, signature);
   869 }
   871 methodOop instanceKlass::find_method(objArrayOop methods, symbolOop name, symbolOop signature) {
   872   int len = methods->length();
   873   // methods are sorted, so do binary search
   874   int l = 0;
   875   int h = len - 1;
   876   while (l <= h) {
   877     int mid = (l + h) >> 1;
   878     methodOop m = (methodOop)methods->obj_at(mid);
   879     assert(m->is_method(), "must be method");
   880     int res = m->name()->fast_compare(name);
   881     if (res == 0) {
   882       // found matching name; do linear search to find matching signature
   883       // first, quick check for common case
   884       if (m->signature() == signature) return m;
   885       // search downwards through overloaded methods
   886       int i;
   887       for (i = mid - 1; i >= l; i--) {
   888         methodOop m = (methodOop)methods->obj_at(i);
   889         assert(m->is_method(), "must be method");
   890         if (m->name() != name) break;
   891         if (m->signature() == signature) return m;
   892       }
   893       // search upwards
   894       for (i = mid + 1; i <= h; i++) {
   895         methodOop m = (methodOop)methods->obj_at(i);
   896         assert(m->is_method(), "must be method");
   897         if (m->name() != name) break;
   898         if (m->signature() == signature) return m;
   899       }
   900       // not found
   901 #ifdef ASSERT
   902       int index = linear_search(methods, name, signature);
   903       if (index != -1) fatal1("binary search bug: should have found entry %d", index);
   904 #endif
   905       return NULL;
   906     } else if (res < 0) {
   907       l = mid + 1;
   908     } else {
   909       h = mid - 1;
   910     }
   911   }
   912 #ifdef ASSERT
   913   int index = linear_search(methods, name, signature);
   914   if (index != -1) fatal1("binary search bug: should have found entry %d", index);
   915 #endif
   916   return NULL;
   917 }
   919 methodOop instanceKlass::uncached_lookup_method(symbolOop name, symbolOop signature) const {
   920   klassOop klass = as_klassOop();
   921   while (klass != NULL) {
   922     methodOop method = instanceKlass::cast(klass)->find_method(name, signature);
   923     if (method != NULL) return method;
   924     klass = instanceKlass::cast(klass)->super();
   925   }
   926   return NULL;
   927 }
   929 // lookup a method in all the interfaces that this class implements
   930 methodOop instanceKlass::lookup_method_in_all_interfaces(symbolOop name,
   931                                                          symbolOop signature) const {
   932   objArrayOop all_ifs = instanceKlass::cast(as_klassOop())->transitive_interfaces();
   933   int num_ifs = all_ifs->length();
   934   instanceKlass *ik = NULL;
   935   for (int i = 0; i < num_ifs; i++) {
   936     ik = instanceKlass::cast(klassOop(all_ifs->obj_at(i)));
   937     methodOop m = ik->lookup_method(name, signature);
   938     if (m != NULL) {
   939       return m;
   940     }
   941   }
   942   return NULL;
   943 }
   945 /* jni_id_for_impl for jfieldIds only */
   946 JNIid* instanceKlass::jni_id_for_impl(instanceKlassHandle this_oop, int offset) {
   947   MutexLocker ml(JfieldIdCreation_lock);
   948   // Retry lookup after we got the lock
   949   JNIid* probe = this_oop->jni_ids() == NULL ? NULL : this_oop->jni_ids()->find(offset);
   950   if (probe == NULL) {
   951     // Slow case, allocate new static field identifier
   952     probe = new JNIid(this_oop->as_klassOop(), offset, this_oop->jni_ids());
   953     this_oop->set_jni_ids(probe);
   954   }
   955   return probe;
   956 }
   959 /* jni_id_for for jfieldIds only */
   960 JNIid* instanceKlass::jni_id_for(int offset) {
   961   JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset);
   962   if (probe == NULL) {
   963     probe = jni_id_for_impl(this->as_klassOop(), offset);
   964   }
   965   return probe;
   966 }
   969 // Lookup or create a jmethodID.
   970 // This code is called by the VMThread and JavaThreads so the
   971 // locking has to be done very carefully to avoid deadlocks
   972 // and/or other cache consistency problems.
   973 //
   974 jmethodID instanceKlass::get_jmethod_id(instanceKlassHandle ik_h, methodHandle method_h) {
   975   size_t idnum = (size_t)method_h->method_idnum();
   976   jmethodID* jmeths = ik_h->methods_jmethod_ids_acquire();
   977   size_t length = 0;
   978   jmethodID id = NULL;
   980   // We use a double-check locking idiom here because this cache is
   981   // performance sensitive. In the normal system, this cache only
   982   // transitions from NULL to non-NULL which is safe because we use
   983   // release_set_methods_jmethod_ids() to advertise the new cache.
   984   // A partially constructed cache should never be seen by a racing
   985   // thread. We also use release_store_ptr() to save a new jmethodID
   986   // in the cache so a partially constructed jmethodID should never be
   987   // seen either. Cache reads of existing jmethodIDs proceed without a
   988   // lock, but cache writes of a new jmethodID requires uniqueness and
   989   // creation of the cache itself requires no leaks so a lock is
   990   // generally acquired in those two cases.
   991   //
   992   // If the RedefineClasses() API has been used, then this cache can
   993   // grow and we'll have transitions from non-NULL to bigger non-NULL.
   994   // Cache creation requires no leaks and we require safety between all
   995   // cache accesses and freeing of the old cache so a lock is generally
   996   // acquired when the RedefineClasses() API has been used.
   998   if (jmeths != NULL) {
   999     // the cache already exists
  1000     if (!ik_h->idnum_can_increment()) {
  1001       // the cache can't grow so we can just get the current values
  1002       get_jmethod_id_length_value(jmeths, idnum, &length, &id);
  1003     } else {
  1004       // cache can grow so we have to be more careful
  1005       if (Threads::number_of_threads() == 0 ||
  1006           SafepointSynchronize::is_at_safepoint()) {
  1007         // we're single threaded or at a safepoint - no locking needed
  1008         get_jmethod_id_length_value(jmeths, idnum, &length, &id);
  1009       } else {
  1010         MutexLocker ml(JmethodIdCreation_lock);
  1011         get_jmethod_id_length_value(jmeths, idnum, &length, &id);
  1015   // implied else:
  1016   // we need to allocate a cache so default length and id values are good
  1018   if (jmeths == NULL ||   // no cache yet
  1019       length <= idnum ||  // cache is too short
  1020       id == NULL) {       // cache doesn't contain entry
  1022     // This function can be called by the VMThread so we have to do all
  1023     // things that might block on a safepoint before grabbing the lock.
  1024     // Otherwise, we can deadlock with the VMThread or have a cache
  1025     // consistency issue. These vars keep track of what we might have
  1026     // to free after the lock is dropped.
  1027     jmethodID  to_dealloc_id     = NULL;
  1028     jmethodID* to_dealloc_jmeths = NULL;
  1030     // may not allocate new_jmeths or use it if we allocate it
  1031     jmethodID* new_jmeths = NULL;
  1032     if (length <= idnum) {
  1033       // allocate a new cache that might be used
  1034       size_t size = MAX2(idnum+1, (size_t)ik_h->idnum_allocated_count());
  1035       new_jmeths = NEW_C_HEAP_ARRAY(jmethodID, size+1);
  1036       memset(new_jmeths, 0, (size+1)*sizeof(jmethodID));
  1037       // cache size is stored in element[0], other elements offset by one
  1038       new_jmeths[0] = (jmethodID)size;
  1041     // allocate a new jmethodID that might be used
  1042     jmethodID new_id = NULL;
  1043     if (method_h->is_old() && !method_h->is_obsolete()) {
  1044       // The method passed in is old (but not obsolete), we need to use the current version
  1045       methodOop current_method = ik_h->method_with_idnum((int)idnum);
  1046       assert(current_method != NULL, "old and but not obsolete, so should exist");
  1047       methodHandle current_method_h(current_method == NULL? method_h() : current_method);
  1048       new_id = JNIHandles::make_jmethod_id(current_method_h);
  1049     } else {
  1050       // It is the current version of the method or an obsolete method,
  1051       // use the version passed in
  1052       new_id = JNIHandles::make_jmethod_id(method_h);
  1055     if (Threads::number_of_threads() == 0 ||
  1056         SafepointSynchronize::is_at_safepoint()) {
  1057       // we're single threaded or at a safepoint - no locking needed
  1058       id = get_jmethod_id_fetch_or_update(ik_h, idnum, new_id, new_jmeths,
  1059                                           &to_dealloc_id, &to_dealloc_jmeths);
  1060     } else {
  1061       MutexLocker ml(JmethodIdCreation_lock);
  1062       id = get_jmethod_id_fetch_or_update(ik_h, idnum, new_id, new_jmeths,
  1063                                           &to_dealloc_id, &to_dealloc_jmeths);
  1066     // The lock has been dropped so we can free resources.
  1067     // Free up either the old cache or the new cache if we allocated one.
  1068     if (to_dealloc_jmeths != NULL) {
  1069       FreeHeap(to_dealloc_jmeths);
  1071     // free up the new ID since it wasn't needed
  1072     if (to_dealloc_id != NULL) {
  1073       JNIHandles::destroy_jmethod_id(to_dealloc_id);
  1076   return id;
  1080 // Common code to fetch the jmethodID from the cache or update the
  1081 // cache with the new jmethodID. This function should never do anything
  1082 // that causes the caller to go to a safepoint or we can deadlock with
  1083 // the VMThread or have cache consistency issues.
  1084 //
  1085 jmethodID instanceKlass::get_jmethod_id_fetch_or_update(
  1086             instanceKlassHandle ik_h, size_t idnum, jmethodID new_id,
  1087             jmethodID* new_jmeths, jmethodID* to_dealloc_id_p,
  1088             jmethodID** to_dealloc_jmeths_p) {
  1089   assert(new_id != NULL, "sanity check");
  1090   assert(to_dealloc_id_p != NULL, "sanity check");
  1091   assert(to_dealloc_jmeths_p != NULL, "sanity check");
  1092   assert(Threads::number_of_threads() == 0 ||
  1093          SafepointSynchronize::is_at_safepoint() ||
  1094          JmethodIdCreation_lock->owned_by_self(), "sanity check");
  1096   // reacquire the cache - we are locked, single threaded or at a safepoint
  1097   jmethodID* jmeths = ik_h->methods_jmethod_ids_acquire();
  1098   jmethodID  id     = NULL;
  1099   size_t     length = 0;
  1101   if (jmeths == NULL ||                         // no cache yet
  1102       (length = (size_t)jmeths[0]) <= idnum) {  // cache is too short
  1103     if (jmeths != NULL) {
  1104       // copy any existing entries from the old cache
  1105       for (size_t index = 0; index < length; index++) {
  1106         new_jmeths[index+1] = jmeths[index+1];
  1108       *to_dealloc_jmeths_p = jmeths;  // save old cache for later delete
  1110     ik_h->release_set_methods_jmethod_ids(jmeths = new_jmeths);
  1111   } else {
  1112     // fetch jmethodID (if any) from the existing cache
  1113     id = jmeths[idnum+1];
  1114     *to_dealloc_jmeths_p = new_jmeths;  // save new cache for later delete
  1116   if (id == NULL) {
  1117     // No matching jmethodID in the existing cache or we have a new
  1118     // cache or we just grew the cache. This cache write is done here
  1119     // by the first thread to win the foot race because a jmethodID
  1120     // needs to be unique once it is generally available.
  1121     id = new_id;
  1123     // The jmethodID cache can be read while unlocked so we have to
  1124     // make sure the new jmethodID is complete before installing it
  1125     // in the cache.
  1126     OrderAccess::release_store_ptr(&jmeths[idnum+1], id);
  1127   } else {
  1128     *to_dealloc_id_p = new_id; // save new id for later delete
  1130   return id;
  1134 // Common code to get the jmethodID cache length and the jmethodID
  1135 // value at index idnum if there is one.
  1136 //
  1137 void instanceKlass::get_jmethod_id_length_value(jmethodID* cache,
  1138        size_t idnum, size_t *length_p, jmethodID* id_p) {
  1139   assert(cache != NULL, "sanity check");
  1140   assert(length_p != NULL, "sanity check");
  1141   assert(id_p != NULL, "sanity check");
  1143   // cache size is stored in element[0], other elements offset by one
  1144   *length_p = (size_t)cache[0];
  1145   if (*length_p <= idnum) {  // cache is too short
  1146     *id_p = NULL;
  1147   } else {
  1148     *id_p = cache[idnum+1];  // fetch jmethodID (if any)
  1153 // Lookup a jmethodID, NULL if not found.  Do no blocking, no allocations, no handles
  1154 jmethodID instanceKlass::jmethod_id_or_null(methodOop method) {
  1155   size_t idnum = (size_t)method->method_idnum();
  1156   jmethodID* jmeths = methods_jmethod_ids_acquire();
  1157   size_t length;                                // length assigned as debugging crumb
  1158   jmethodID id = NULL;
  1159   if (jmeths != NULL &&                         // If there is a cache
  1160       (length = (size_t)jmeths[0]) > idnum) {   // and if it is long enough,
  1161     id = jmeths[idnum+1];                       // Look up the id (may be NULL)
  1163   return id;
  1167 // Cache an itable index
  1168 void instanceKlass::set_cached_itable_index(size_t idnum, int index) {
  1169   int* indices = methods_cached_itable_indices_acquire();
  1170   int* to_dealloc_indices = NULL;
  1172   // We use a double-check locking idiom here because this cache is
  1173   // performance sensitive. In the normal system, this cache only
  1174   // transitions from NULL to non-NULL which is safe because we use
  1175   // release_set_methods_cached_itable_indices() to advertise the
  1176   // new cache. A partially constructed cache should never be seen
  1177   // by a racing thread. Cache reads and writes proceed without a
  1178   // lock, but creation of the cache itself requires no leaks so a
  1179   // lock is generally acquired in that case.
  1180   //
  1181   // If the RedefineClasses() API has been used, then this cache can
  1182   // grow and we'll have transitions from non-NULL to bigger non-NULL.
  1183   // Cache creation requires no leaks and we require safety between all
  1184   // cache accesses and freeing of the old cache so a lock is generally
  1185   // acquired when the RedefineClasses() API has been used.
  1187   if (indices == NULL || idnum_can_increment()) {
  1188     // we need a cache or the cache can grow
  1189     MutexLocker ml(JNICachedItableIndex_lock);
  1190     // reacquire the cache to see if another thread already did the work
  1191     indices = methods_cached_itable_indices_acquire();
  1192     size_t length = 0;
  1193     // cache size is stored in element[0], other elements offset by one
  1194     if (indices == NULL || (length = (size_t)indices[0]) <= idnum) {
  1195       size_t size = MAX2(idnum+1, (size_t)idnum_allocated_count());
  1196       int* new_indices = NEW_C_HEAP_ARRAY(int, size+1);
  1197       new_indices[0] = (int)size;
  1198       // copy any existing entries
  1199       size_t i;
  1200       for (i = 0; i < length; i++) {
  1201         new_indices[i+1] = indices[i+1];
  1203       // Set all the rest to -1
  1204       for (i = length; i < size; i++) {
  1205         new_indices[i+1] = -1;
  1207       if (indices != NULL) {
  1208         // We have an old cache to delete so save it for after we
  1209         // drop the lock.
  1210         to_dealloc_indices = indices;
  1212       release_set_methods_cached_itable_indices(indices = new_indices);
  1215     if (idnum_can_increment()) {
  1216       // this cache can grow so we have to write to it safely
  1217       indices[idnum+1] = index;
  1219   } else {
  1220     CHECK_UNHANDLED_OOPS_ONLY(Thread::current()->clear_unhandled_oops());
  1223   if (!idnum_can_increment()) {
  1224     // The cache cannot grow and this JNI itable index value does not
  1225     // have to be unique like a jmethodID. If there is a race to set it,
  1226     // it doesn't matter.
  1227     indices[idnum+1] = index;
  1230   if (to_dealloc_indices != NULL) {
  1231     // we allocated a new cache so free the old one
  1232     FreeHeap(to_dealloc_indices);
  1237 // Retrieve a cached itable index
  1238 int instanceKlass::cached_itable_index(size_t idnum) {
  1239   int* indices = methods_cached_itable_indices_acquire();
  1240   if (indices != NULL && ((size_t)indices[0]) > idnum) {
  1241      // indices exist and are long enough, retrieve possible cached
  1242     return indices[idnum+1];
  1244   return -1;
  1248 //
  1249 // nmethodBucket is used to record dependent nmethods for
  1250 // deoptimization.  nmethod dependencies are actually <klass, method>
  1251 // pairs but we really only care about the klass part for purposes of
  1252 // finding nmethods which might need to be deoptimized.  Instead of
  1253 // recording the method, a count of how many times a particular nmethod
  1254 // was recorded is kept.  This ensures that any recording errors are
  1255 // noticed since an nmethod should be removed as many times are it's
  1256 // added.
  1257 //
  1258 class nmethodBucket {
  1259  private:
  1260   nmethod*       _nmethod;
  1261   int            _count;
  1262   nmethodBucket* _next;
  1264  public:
  1265   nmethodBucket(nmethod* nmethod, nmethodBucket* next) {
  1266     _nmethod = nmethod;
  1267     _next = next;
  1268     _count = 1;
  1270   int count()                             { return _count; }
  1271   int increment()                         { _count += 1; return _count; }
  1272   int decrement()                         { _count -= 1; assert(_count >= 0, "don't underflow"); return _count; }
  1273   nmethodBucket* next()                   { return _next; }
  1274   void set_next(nmethodBucket* b)         { _next = b; }
  1275   nmethod* get_nmethod()                  { return _nmethod; }
  1276 };
  1279 //
  1280 // Walk the list of dependent nmethods searching for nmethods which
  1281 // are dependent on the klassOop that was passed in and mark them for
  1282 // deoptimization.  Returns the number of nmethods found.
  1283 //
  1284 int instanceKlass::mark_dependent_nmethods(DepChange& changes) {
  1285   assert_locked_or_safepoint(CodeCache_lock);
  1286   int found = 0;
  1287   nmethodBucket* b = _dependencies;
  1288   while (b != NULL) {
  1289     nmethod* nm = b->get_nmethod();
  1290     // since dependencies aren't removed until an nmethod becomes a zombie,
  1291     // the dependency list may contain nmethods which aren't alive.
  1292     if (nm->is_alive() && !nm->is_marked_for_deoptimization() && nm->check_dependency_on(changes)) {
  1293       if (TraceDependencies) {
  1294         ResourceMark rm;
  1295         tty->print_cr("Marked for deoptimization");
  1296         tty->print_cr("  context = %s", this->external_name());
  1297         changes.print();
  1298         nm->print();
  1299         nm->print_dependencies();
  1301       nm->mark_for_deoptimization();
  1302       found++;
  1304     b = b->next();
  1306   return found;
  1310 //
  1311 // Add an nmethodBucket to the list of dependencies for this nmethod.
  1312 // It's possible that an nmethod has multiple dependencies on this klass
  1313 // so a count is kept for each bucket to guarantee that creation and
  1314 // deletion of dependencies is consistent.
  1315 //
  1316 void instanceKlass::add_dependent_nmethod(nmethod* nm) {
  1317   assert_locked_or_safepoint(CodeCache_lock);
  1318   nmethodBucket* b = _dependencies;
  1319   nmethodBucket* last = NULL;
  1320   while (b != NULL) {
  1321     if (nm == b->get_nmethod()) {
  1322       b->increment();
  1323       return;
  1325     b = b->next();
  1327   _dependencies = new nmethodBucket(nm, _dependencies);
  1331 //
  1332 // Decrement count of the nmethod in the dependency list and remove
  1333 // the bucket competely when the count goes to 0.  This method must
  1334 // find a corresponding bucket otherwise there's a bug in the
  1335 // recording of dependecies.
  1336 //
  1337 void instanceKlass::remove_dependent_nmethod(nmethod* nm) {
  1338   assert_locked_or_safepoint(CodeCache_lock);
  1339   nmethodBucket* b = _dependencies;
  1340   nmethodBucket* last = NULL;
  1341   while (b != NULL) {
  1342     if (nm == b->get_nmethod()) {
  1343       if (b->decrement() == 0) {
  1344         if (last == NULL) {
  1345           _dependencies = b->next();
  1346         } else {
  1347           last->set_next(b->next());
  1349         delete b;
  1351       return;
  1353     last = b;
  1354     b = b->next();
  1356 #ifdef ASSERT
  1357   tty->print_cr("### %s can't find dependent nmethod:", this->external_name());
  1358   nm->print();
  1359 #endif // ASSERT
  1360   ShouldNotReachHere();
  1364 #ifndef PRODUCT
  1365 void instanceKlass::print_dependent_nmethods(bool verbose) {
  1366   nmethodBucket* b = _dependencies;
  1367   int idx = 0;
  1368   while (b != NULL) {
  1369     nmethod* nm = b->get_nmethod();
  1370     tty->print("[%d] count=%d { ", idx++, b->count());
  1371     if (!verbose) {
  1372       nm->print_on(tty, "nmethod");
  1373       tty->print_cr(" } ");
  1374     } else {
  1375       nm->print();
  1376       nm->print_dependencies();
  1377       tty->print_cr("--- } ");
  1379     b = b->next();
  1384 bool instanceKlass::is_dependent_nmethod(nmethod* nm) {
  1385   nmethodBucket* b = _dependencies;
  1386   while (b != NULL) {
  1387     if (nm == b->get_nmethod()) {
  1388       return true;
  1390     b = b->next();
  1392   return false;
  1394 #endif //PRODUCT
  1397 #ifdef ASSERT
  1398 template <class T> void assert_is_in(T *p) {
  1399   T heap_oop = oopDesc::load_heap_oop(p);
  1400   if (!oopDesc::is_null(heap_oop)) {
  1401     oop o = oopDesc::decode_heap_oop_not_null(heap_oop);
  1402     assert(Universe::heap()->is_in(o), "should be in heap");
  1405 template <class T> void assert_is_in_closed_subset(T *p) {
  1406   T heap_oop = oopDesc::load_heap_oop(p);
  1407   if (!oopDesc::is_null(heap_oop)) {
  1408     oop o = oopDesc::decode_heap_oop_not_null(heap_oop);
  1409     assert(Universe::heap()->is_in_closed_subset(o), "should be in closed");
  1412 template <class T> void assert_is_in_reserved(T *p) {
  1413   T heap_oop = oopDesc::load_heap_oop(p);
  1414   if (!oopDesc::is_null(heap_oop)) {
  1415     oop o = oopDesc::decode_heap_oop_not_null(heap_oop);
  1416     assert(Universe::heap()->is_in_reserved(o), "should be in reserved");
  1419 template <class T> void assert_nothing(T *p) {}
  1421 #else
  1422 template <class T> void assert_is_in(T *p) {}
  1423 template <class T> void assert_is_in_closed_subset(T *p) {}
  1424 template <class T> void assert_is_in_reserved(T *p) {}
  1425 template <class T> void assert_nothing(T *p) {}
  1426 #endif // ASSERT
  1428 //
  1429 // Macros that iterate over areas of oops which are specialized on type of
  1430 // oop pointer either narrow or wide, depending on UseCompressedOops
  1431 //
  1432 // Parameters are:
  1433 //   T         - type of oop to point to (either oop or narrowOop)
  1434 //   start_p   - starting pointer for region to iterate over
  1435 //   count     - number of oops or narrowOops to iterate over
  1436 //   do_oop    - action to perform on each oop (it's arbitrary C code which
  1437 //               makes it more efficient to put in a macro rather than making
  1438 //               it a template function)
  1439 //   assert_fn - assert function which is template function because performance
  1440 //               doesn't matter when enabled.
  1441 #define InstanceKlass_SPECIALIZED_OOP_ITERATE( \
  1442   T, start_p, count, do_oop,                \
  1443   assert_fn)                                \
  1444 {                                           \
  1445   T* p         = (T*)(start_p);             \
  1446   T* const end = p + (count);               \
  1447   while (p < end) {                         \
  1448     (assert_fn)(p);                         \
  1449     do_oop;                                 \
  1450     ++p;                                    \
  1451   }                                         \
  1454 #define InstanceKlass_SPECIALIZED_OOP_REVERSE_ITERATE( \
  1455   T, start_p, count, do_oop,                \
  1456   assert_fn)                                \
  1457 {                                           \
  1458   T* const start = (T*)(start_p);           \
  1459   T*       p     = start + (count);         \
  1460   while (start < p) {                       \
  1461     --p;                                    \
  1462     (assert_fn)(p);                         \
  1463     do_oop;                                 \
  1464   }                                         \
  1467 #define InstanceKlass_SPECIALIZED_BOUNDED_OOP_ITERATE( \
  1468   T, start_p, count, low, high,             \
  1469   do_oop, assert_fn)                        \
  1470 {                                           \
  1471   T* const l = (T*)(low);                   \
  1472   T* const h = (T*)(high);                  \
  1473   assert(mask_bits((intptr_t)l, sizeof(T)-1) == 0 && \
  1474          mask_bits((intptr_t)h, sizeof(T)-1) == 0,   \
  1475          "bounded region must be properly aligned"); \
  1476   T* p       = (T*)(start_p);               \
  1477   T* end     = p + (count);                 \
  1478   if (p < l) p = l;                         \
  1479   if (end > h) end = h;                     \
  1480   while (p < end) {                         \
  1481     (assert_fn)(p);                         \
  1482     do_oop;                                 \
  1483     ++p;                                    \
  1484   }                                         \
  1488 // The following macros call specialized macros, passing either oop or
  1489 // narrowOop as the specialization type.  These test the UseCompressedOops
  1490 // flag.
  1491 #define InstanceKlass_OOP_ITERATE(start_p, count,    \
  1492                                   do_oop, assert_fn) \
  1493 {                                                    \
  1494   if (UseCompressedOops) {                           \
  1495     InstanceKlass_SPECIALIZED_OOP_ITERATE(narrowOop, \
  1496       start_p, count,                                \
  1497       do_oop, assert_fn)                             \
  1498   } else {                                           \
  1499     InstanceKlass_SPECIALIZED_OOP_ITERATE(oop,       \
  1500       start_p, count,                                \
  1501       do_oop, assert_fn)                             \
  1502   }                                                  \
  1505 #define InstanceKlass_BOUNDED_OOP_ITERATE(start_p, count, low, high,    \
  1506                                           do_oop, assert_fn) \
  1507 {                                                            \
  1508   if (UseCompressedOops) {                                   \
  1509     InstanceKlass_SPECIALIZED_BOUNDED_OOP_ITERATE(narrowOop, \
  1510       start_p, count,                                        \
  1511       low, high,                                             \
  1512       do_oop, assert_fn)                                     \
  1513   } else {                                                   \
  1514     InstanceKlass_SPECIALIZED_BOUNDED_OOP_ITERATE(oop,       \
  1515       start_p, count,                                        \
  1516       low, high,                                             \
  1517       do_oop, assert_fn)                                     \
  1518   }                                                          \
  1521 #define InstanceKlass_OOP_MAP_ITERATE(obj, do_oop, assert_fn)            \
  1522 {                                                                        \
  1523   /* Compute oopmap block range. The common case                         \
  1524      is nonstatic_oop_map_size == 1. */                                  \
  1525   OopMapBlock* map           = start_of_nonstatic_oop_maps();            \
  1526   OopMapBlock* const end_map = map + nonstatic_oop_map_count();          \
  1527   if (UseCompressedOops) {                                               \
  1528     while (map < end_map) {                                              \
  1529       InstanceKlass_SPECIALIZED_OOP_ITERATE(narrowOop,                   \
  1530         obj->obj_field_addr<narrowOop>(map->offset()), map->count(),     \
  1531         do_oop, assert_fn)                                               \
  1532       ++map;                                                             \
  1533     }                                                                    \
  1534   } else {                                                               \
  1535     while (map < end_map) {                                              \
  1536       InstanceKlass_SPECIALIZED_OOP_ITERATE(oop,                         \
  1537         obj->obj_field_addr<oop>(map->offset()), map->count(),           \
  1538         do_oop, assert_fn)                                               \
  1539       ++map;                                                             \
  1540     }                                                                    \
  1541   }                                                                      \
  1544 #define InstanceKlass_OOP_MAP_REVERSE_ITERATE(obj, do_oop, assert_fn)    \
  1545 {                                                                        \
  1546   OopMapBlock* const start_map = start_of_nonstatic_oop_maps();          \
  1547   OopMapBlock* map             = start_map + nonstatic_oop_map_count();  \
  1548   if (UseCompressedOops) {                                               \
  1549     while (start_map < map) {                                            \
  1550       --map;                                                             \
  1551       InstanceKlass_SPECIALIZED_OOP_REVERSE_ITERATE(narrowOop,           \
  1552         obj->obj_field_addr<narrowOop>(map->offset()), map->count(),     \
  1553         do_oop, assert_fn)                                               \
  1554     }                                                                    \
  1555   } else {                                                               \
  1556     while (start_map < map) {                                            \
  1557       --map;                                                             \
  1558       InstanceKlass_SPECIALIZED_OOP_REVERSE_ITERATE(oop,                 \
  1559         obj->obj_field_addr<oop>(map->offset()), map->count(),           \
  1560         do_oop, assert_fn)                                               \
  1561     }                                                                    \
  1562   }                                                                      \
  1565 #define InstanceKlass_BOUNDED_OOP_MAP_ITERATE(obj, low, high, do_oop,    \
  1566                                               assert_fn)                 \
  1567 {                                                                        \
  1568   /* Compute oopmap block range. The common case is                      \
  1569      nonstatic_oop_map_size == 1, so we accept the                       \
  1570      usually non-existent extra overhead of examining                    \
  1571      all the maps. */                                                    \
  1572   OopMapBlock* map           = start_of_nonstatic_oop_maps();            \
  1573   OopMapBlock* const end_map = map + nonstatic_oop_map_count();          \
  1574   if (UseCompressedOops) {                                               \
  1575     while (map < end_map) {                                              \
  1576       InstanceKlass_SPECIALIZED_BOUNDED_OOP_ITERATE(narrowOop,           \
  1577         obj->obj_field_addr<narrowOop>(map->offset()), map->count(),     \
  1578         low, high,                                                       \
  1579         do_oop, assert_fn)                                               \
  1580       ++map;                                                             \
  1581     }                                                                    \
  1582   } else {                                                               \
  1583     while (map < end_map) {                                              \
  1584       InstanceKlass_SPECIALIZED_BOUNDED_OOP_ITERATE(oop,                 \
  1585         obj->obj_field_addr<oop>(map->offset()), map->count(),           \
  1586         low, high,                                                       \
  1587         do_oop, assert_fn)                                               \
  1588       ++map;                                                             \
  1589     }                                                                    \
  1590   }                                                                      \
  1593 void instanceKlass::follow_static_fields() {
  1594   InstanceKlass_OOP_ITERATE( \
  1595     start_of_static_fields(), static_oop_field_size(), \
  1596     MarkSweep::mark_and_push(p), \
  1597     assert_is_in_closed_subset)
  1600 #ifndef SERIALGC
  1601 void instanceKlass::follow_static_fields(ParCompactionManager* cm) {
  1602   InstanceKlass_OOP_ITERATE( \
  1603     start_of_static_fields(), static_oop_field_size(), \
  1604     PSParallelCompact::mark_and_push(cm, p), \
  1605     assert_is_in)
  1607 #endif // SERIALGC
  1609 void instanceKlass::adjust_static_fields() {
  1610   InstanceKlass_OOP_ITERATE( \
  1611     start_of_static_fields(), static_oop_field_size(), \
  1612     MarkSweep::adjust_pointer(p), \
  1613     assert_nothing)
  1616 #ifndef SERIALGC
  1617 void instanceKlass::update_static_fields() {
  1618   InstanceKlass_OOP_ITERATE( \
  1619     start_of_static_fields(), static_oop_field_size(), \
  1620     PSParallelCompact::adjust_pointer(p), \
  1621     assert_nothing)
  1624 void instanceKlass::update_static_fields(HeapWord* beg_addr, HeapWord* end_addr) {
  1625   InstanceKlass_BOUNDED_OOP_ITERATE( \
  1626     start_of_static_fields(), static_oop_field_size(), \
  1627     beg_addr, end_addr, \
  1628     PSParallelCompact::adjust_pointer(p), \
  1629     assert_nothing )
  1631 #endif // SERIALGC
  1633 void instanceKlass::oop_follow_contents(oop obj) {
  1634   assert(obj != NULL, "can't follow the content of NULL object");
  1635   obj->follow_header();
  1636   InstanceKlass_OOP_MAP_ITERATE( \
  1637     obj, \
  1638     MarkSweep::mark_and_push(p), \
  1639     assert_is_in_closed_subset)
  1642 #ifndef SERIALGC
  1643 void instanceKlass::oop_follow_contents(ParCompactionManager* cm,
  1644                                         oop obj) {
  1645   assert(obj != NULL, "can't follow the content of NULL object");
  1646   obj->follow_header(cm);
  1647   InstanceKlass_OOP_MAP_ITERATE( \
  1648     obj, \
  1649     PSParallelCompact::mark_and_push(cm, p), \
  1650     assert_is_in)
  1652 #endif // SERIALGC
  1654 // closure's do_header() method dicates whether the given closure should be
  1655 // applied to the klass ptr in the object header.
  1657 #define InstanceKlass_OOP_OOP_ITERATE_DEFN(OopClosureType, nv_suffix)        \
  1659 int instanceKlass::oop_oop_iterate##nv_suffix(oop obj, OopClosureType* closure) { \
  1660   SpecializationStats::record_iterate_call##nv_suffix(SpecializationStats::ik);\
  1661   /* header */                                                          \
  1662   if (closure->do_header()) {                                           \
  1663     obj->oop_iterate_header(closure);                                   \
  1664   }                                                                     \
  1665   InstanceKlass_OOP_MAP_ITERATE(                                        \
  1666     obj,                                                                \
  1667     SpecializationStats::                                               \
  1668       record_do_oop_call##nv_suffix(SpecializationStats::ik);           \
  1669     (closure)->do_oop##nv_suffix(p),                                    \
  1670     assert_is_in_closed_subset)                                         \
  1671   return size_helper();                                                 \
  1674 #ifndef SERIALGC
  1675 #define InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DEFN(OopClosureType, nv_suffix) \
  1677 int instanceKlass::oop_oop_iterate_backwards##nv_suffix(oop obj,                \
  1678                                               OopClosureType* closure) {        \
  1679   SpecializationStats::record_iterate_call##nv_suffix(SpecializationStats::ik); \
  1680   /* header */                                                                  \
  1681   if (closure->do_header()) {                                                   \
  1682     obj->oop_iterate_header(closure);                                           \
  1683   }                                                                             \
  1684   /* instance variables */                                                      \
  1685   InstanceKlass_OOP_MAP_REVERSE_ITERATE(                                        \
  1686     obj,                                                                        \
  1687     SpecializationStats::record_do_oop_call##nv_suffix(SpecializationStats::ik);\
  1688     (closure)->do_oop##nv_suffix(p),                                            \
  1689     assert_is_in_closed_subset)                                                 \
  1690    return size_helper();                                                        \
  1692 #endif // !SERIALGC
  1694 #define InstanceKlass_OOP_OOP_ITERATE_DEFN_m(OopClosureType, nv_suffix) \
  1696 int instanceKlass::oop_oop_iterate##nv_suffix##_m(oop obj,              \
  1697                                                   OopClosureType* closure, \
  1698                                                   MemRegion mr) {          \
  1699   SpecializationStats::record_iterate_call##nv_suffix(SpecializationStats::ik);\
  1700   if (closure->do_header()) {                                            \
  1701     obj->oop_iterate_header(closure, mr);                                \
  1702   }                                                                      \
  1703   InstanceKlass_BOUNDED_OOP_MAP_ITERATE(                                 \
  1704     obj, mr.start(), mr.end(),                                           \
  1705     (closure)->do_oop##nv_suffix(p),                                     \
  1706     assert_is_in_closed_subset)                                          \
  1707   return size_helper();                                                  \
  1710 ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_DEFN)
  1711 ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceKlass_OOP_OOP_ITERATE_DEFN)
  1712 ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_DEFN_m)
  1713 ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceKlass_OOP_OOP_ITERATE_DEFN_m)
  1714 #ifndef SERIALGC
  1715 ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DEFN)
  1716 ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DEFN)
  1717 #endif // !SERIALGC
  1719 void instanceKlass::iterate_static_fields(OopClosure* closure) {
  1720     InstanceKlass_OOP_ITERATE( \
  1721       start_of_static_fields(), static_oop_field_size(), \
  1722       closure->do_oop(p), \
  1723       assert_is_in_reserved)
  1726 void instanceKlass::iterate_static_fields(OopClosure* closure,
  1727                                           MemRegion mr) {
  1728   InstanceKlass_BOUNDED_OOP_ITERATE( \
  1729     start_of_static_fields(), static_oop_field_size(), \
  1730     mr.start(), mr.end(), \
  1731     (closure)->do_oop_v(p), \
  1732     assert_is_in_closed_subset)
  1735 int instanceKlass::oop_adjust_pointers(oop obj) {
  1736   int size = size_helper();
  1737   InstanceKlass_OOP_MAP_ITERATE( \
  1738     obj, \
  1739     MarkSweep::adjust_pointer(p), \
  1740     assert_is_in)
  1741   obj->adjust_header();
  1742   return size;
  1745 #ifndef SERIALGC
  1746 void instanceKlass::oop_copy_contents(PSPromotionManager* pm, oop obj) {
  1747   assert(!pm->depth_first(), "invariant");
  1748   InstanceKlass_OOP_MAP_REVERSE_ITERATE( \
  1749     obj, \
  1750     if (PSScavenge::should_scavenge(p)) { \
  1751       pm->claim_or_forward_breadth(p); \
  1752     }, \
  1753     assert_nothing )
  1756 void instanceKlass::oop_push_contents(PSPromotionManager* pm, oop obj) {
  1757   assert(pm->depth_first(), "invariant");
  1758   InstanceKlass_OOP_MAP_REVERSE_ITERATE( \
  1759     obj, \
  1760     if (PSScavenge::should_scavenge(p)) { \
  1761       pm->claim_or_forward_depth(p); \
  1762     }, \
  1763     assert_nothing )
  1766 int instanceKlass::oop_update_pointers(ParCompactionManager* cm, oop obj) {
  1767   InstanceKlass_OOP_MAP_ITERATE( \
  1768     obj, \
  1769     PSParallelCompact::adjust_pointer(p), \
  1770     assert_nothing)
  1771   return size_helper();
  1774 int instanceKlass::oop_update_pointers(ParCompactionManager* cm, oop obj,
  1775                                        HeapWord* beg_addr, HeapWord* end_addr) {
  1776   InstanceKlass_BOUNDED_OOP_MAP_ITERATE( \
  1777     obj, beg_addr, end_addr, \
  1778     PSParallelCompact::adjust_pointer(p), \
  1779     assert_nothing)
  1780   return size_helper();
  1783 void instanceKlass::copy_static_fields(PSPromotionManager* pm) {
  1784   assert(!pm->depth_first(), "invariant");
  1785   InstanceKlass_OOP_ITERATE( \
  1786     start_of_static_fields(), static_oop_field_size(), \
  1787     if (PSScavenge::should_scavenge(p)) { \
  1788       pm->claim_or_forward_breadth(p); \
  1789     }, \
  1790     assert_nothing )
  1793 void instanceKlass::push_static_fields(PSPromotionManager* pm) {
  1794   assert(pm->depth_first(), "invariant");
  1795   InstanceKlass_OOP_ITERATE( \
  1796     start_of_static_fields(), static_oop_field_size(), \
  1797     if (PSScavenge::should_scavenge(p)) { \
  1798       pm->claim_or_forward_depth(p); \
  1799     }, \
  1800     assert_nothing )
  1803 void instanceKlass::copy_static_fields(ParCompactionManager* cm) {
  1804   InstanceKlass_OOP_ITERATE( \
  1805     start_of_static_fields(), static_oop_field_size(), \
  1806     PSParallelCompact::adjust_pointer(p), \
  1807     assert_is_in)
  1809 #endif // SERIALGC
  1811 // This klass is alive but the implementor link is not followed/updated.
  1812 // Subklass and sibling links are handled by Klass::follow_weak_klass_links
  1814 void instanceKlass::follow_weak_klass_links(
  1815   BoolObjectClosure* is_alive, OopClosure* keep_alive) {
  1816   assert(is_alive->do_object_b(as_klassOop()), "this oop should be live");
  1817   if (ClassUnloading) {
  1818     for (int i = 0; i < implementors_limit; i++) {
  1819       klassOop impl = _implementors[i];
  1820       if (impl == NULL)  break;  // no more in the list
  1821       if (!is_alive->do_object_b(impl)) {
  1822         // remove this guy from the list by overwriting him with the tail
  1823         int lasti = --_nof_implementors;
  1824         assert(lasti >= i && lasti < implementors_limit, "just checking");
  1825         _implementors[i] = _implementors[lasti];
  1826         _implementors[lasti] = NULL;
  1827         --i; // rerun the loop at this index
  1830   } else {
  1831     for (int i = 0; i < implementors_limit; i++) {
  1832       keep_alive->do_oop(&adr_implementors()[i]);
  1835   Klass::follow_weak_klass_links(is_alive, keep_alive);
  1838 void instanceKlass::remove_unshareable_info() {
  1839   Klass::remove_unshareable_info();
  1840   init_implementor();
  1843 static void clear_all_breakpoints(methodOop m) {
  1844   m->clear_all_breakpoints();
  1847 void instanceKlass::release_C_heap_structures() {
  1848   // Deallocate oop map cache
  1849   if (_oop_map_cache != NULL) {
  1850     delete _oop_map_cache;
  1851     _oop_map_cache = NULL;
  1854   // Deallocate JNI identifiers for jfieldIDs
  1855   JNIid::deallocate(jni_ids());
  1856   set_jni_ids(NULL);
  1858   jmethodID* jmeths = methods_jmethod_ids_acquire();
  1859   if (jmeths != (jmethodID*)NULL) {
  1860     release_set_methods_jmethod_ids(NULL);
  1861     FreeHeap(jmeths);
  1864   int* indices = methods_cached_itable_indices_acquire();
  1865   if (indices != (int*)NULL) {
  1866     release_set_methods_cached_itable_indices(NULL);
  1867     FreeHeap(indices);
  1870   // release dependencies
  1871   nmethodBucket* b = _dependencies;
  1872   _dependencies = NULL;
  1873   while (b != NULL) {
  1874     nmethodBucket* next = b->next();
  1875     delete b;
  1876     b = next;
  1879   // Deallocate breakpoint records
  1880   if (breakpoints() != 0x0) {
  1881     methods_do(clear_all_breakpoints);
  1882     assert(breakpoints() == 0x0, "should have cleared breakpoints");
  1885   // deallocate information about previous versions
  1886   if (_previous_versions != NULL) {
  1887     for (int i = _previous_versions->length() - 1; i >= 0; i--) {
  1888       PreviousVersionNode * pv_node = _previous_versions->at(i);
  1889       delete pv_node;
  1891     delete _previous_versions;
  1892     _previous_versions = NULL;
  1895   // deallocate the cached class file
  1896   if (_cached_class_file_bytes != NULL) {
  1897     os::free(_cached_class_file_bytes);
  1898     _cached_class_file_bytes = NULL;
  1899     _cached_class_file_len = 0;
  1903 const char* instanceKlass::signature_name() const {
  1904   const char* src = (const char*) (name()->as_C_string());
  1905   const int src_length = (int)strlen(src);
  1906   char* dest = NEW_RESOURCE_ARRAY(char, src_length + 3);
  1907   int src_index = 0;
  1908   int dest_index = 0;
  1909   dest[dest_index++] = 'L';
  1910   while (src_index < src_length) {
  1911     dest[dest_index++] = src[src_index++];
  1913   dest[dest_index++] = ';';
  1914   dest[dest_index] = '\0';
  1915   return dest;
  1918 // different verisons of is_same_class_package
  1919 bool instanceKlass::is_same_class_package(klassOop class2) {
  1920   klassOop class1 = as_klassOop();
  1921   oop classloader1 = instanceKlass::cast(class1)->class_loader();
  1922   symbolOop classname1 = Klass::cast(class1)->name();
  1924   if (Klass::cast(class2)->oop_is_objArray()) {
  1925     class2 = objArrayKlass::cast(class2)->bottom_klass();
  1927   oop classloader2;
  1928   if (Klass::cast(class2)->oop_is_instance()) {
  1929     classloader2 = instanceKlass::cast(class2)->class_loader();
  1930   } else {
  1931     assert(Klass::cast(class2)->oop_is_typeArray(), "should be type array");
  1932     classloader2 = NULL;
  1934   symbolOop classname2 = Klass::cast(class2)->name();
  1936   return instanceKlass::is_same_class_package(classloader1, classname1,
  1937                                               classloader2, classname2);
  1940 bool instanceKlass::is_same_class_package(oop classloader2, symbolOop classname2) {
  1941   klassOop class1 = as_klassOop();
  1942   oop classloader1 = instanceKlass::cast(class1)->class_loader();
  1943   symbolOop classname1 = Klass::cast(class1)->name();
  1945   return instanceKlass::is_same_class_package(classloader1, classname1,
  1946                                               classloader2, classname2);
  1949 // return true if two classes are in the same package, classloader
  1950 // and classname information is enough to determine a class's package
  1951 bool instanceKlass::is_same_class_package(oop class_loader1, symbolOop class_name1,
  1952                                           oop class_loader2, symbolOop class_name2) {
  1953   if (class_loader1 != class_loader2) {
  1954     return false;
  1955   } else if (class_name1 == class_name2) {
  1956     return true;                // skip painful bytewise comparison
  1957   } else {
  1958     ResourceMark rm;
  1960     // The symbolOop's are in UTF8 encoding. Since we only need to check explicitly
  1961     // for ASCII characters ('/', 'L', '['), we can keep them in UTF8 encoding.
  1962     // Otherwise, we just compare jbyte values between the strings.
  1963     jbyte *name1 = class_name1->base();
  1964     jbyte *name2 = class_name2->base();
  1966     jbyte *last_slash1 = UTF8::strrchr(name1, class_name1->utf8_length(), '/');
  1967     jbyte *last_slash2 = UTF8::strrchr(name2, class_name2->utf8_length(), '/');
  1969     if ((last_slash1 == NULL) || (last_slash2 == NULL)) {
  1970       // One of the two doesn't have a package.  Only return true
  1971       // if the other one also doesn't have a package.
  1972       return last_slash1 == last_slash2;
  1973     } else {
  1974       // Skip over '['s
  1975       if (*name1 == '[') {
  1976         do {
  1977           name1++;
  1978         } while (*name1 == '[');
  1979         if (*name1 != 'L') {
  1980           // Something is terribly wrong.  Shouldn't be here.
  1981           return false;
  1984       if (*name2 == '[') {
  1985         do {
  1986           name2++;
  1987         } while (*name2 == '[');
  1988         if (*name2 != 'L') {
  1989           // Something is terribly wrong.  Shouldn't be here.
  1990           return false;
  1994       // Check that package part is identical
  1995       int length1 = last_slash1 - name1;
  1996       int length2 = last_slash2 - name2;
  1998       return UTF8::equal(name1, length1, name2, length2);
  2003 // Returns true iff super_method can be overridden by a method in targetclassname
  2004 // See JSL 3rd edition 8.4.6.1
  2005 // Assumes name-signature match
  2006 // "this" is instanceKlass of super_method which must exist
  2007 // note that the instanceKlass of the method in the targetclassname has not always been created yet
  2008 bool instanceKlass::is_override(methodHandle super_method, Handle targetclassloader, symbolHandle targetclassname, TRAPS) {
  2009    // Private methods can not be overridden
  2010    if (super_method->is_private()) {
  2011      return false;
  2013    // If super method is accessible, then override
  2014    if ((super_method->is_protected()) ||
  2015        (super_method->is_public())) {
  2016      return true;
  2018    // Package-private methods are not inherited outside of package
  2019    assert(super_method->is_package_private(), "must be package private");
  2020    return(is_same_class_package(targetclassloader(), targetclassname()));
  2023 /* defined for now in jvm.cpp, for historical reasons *--
  2024 klassOop instanceKlass::compute_enclosing_class_impl(instanceKlassHandle self,
  2025                                                      symbolOop& simple_name_result, TRAPS) {
  2026   ...
  2028 */
  2030 // tell if two classes have the same enclosing class (at package level)
  2031 bool instanceKlass::is_same_package_member_impl(instanceKlassHandle class1,
  2032                                                 klassOop class2_oop, TRAPS) {
  2033   if (class2_oop == class1->as_klassOop())          return true;
  2034   if (!Klass::cast(class2_oop)->oop_is_instance())  return false;
  2035   instanceKlassHandle class2(THREAD, class2_oop);
  2037   // must be in same package before we try anything else
  2038   if (!class1->is_same_class_package(class2->class_loader(), class2->name()))
  2039     return false;
  2041   // As long as there is an outer1.getEnclosingClass,
  2042   // shift the search outward.
  2043   instanceKlassHandle outer1 = class1;
  2044   for (;;) {
  2045     // As we walk along, look for equalities between outer1 and class2.
  2046     // Eventually, the walks will terminate as outer1 stops
  2047     // at the top-level class around the original class.
  2048     bool ignore_inner_is_member;
  2049     klassOop next = outer1->compute_enclosing_class(&ignore_inner_is_member,
  2050                                                     CHECK_false);
  2051     if (next == NULL)  break;
  2052     if (next == class2())  return true;
  2053     outer1 = instanceKlassHandle(THREAD, next);
  2056   // Now do the same for class2.
  2057   instanceKlassHandle outer2 = class2;
  2058   for (;;) {
  2059     bool ignore_inner_is_member;
  2060     klassOop next = outer2->compute_enclosing_class(&ignore_inner_is_member,
  2061                                                     CHECK_false);
  2062     if (next == NULL)  break;
  2063     // Might as well check the new outer against all available values.
  2064     if (next == class1())  return true;
  2065     if (next == outer1())  return true;
  2066     outer2 = instanceKlassHandle(THREAD, next);
  2069   // If by this point we have not found an equality between the
  2070   // two classes, we know they are in separate package members.
  2071   return false;
  2075 jint instanceKlass::compute_modifier_flags(TRAPS) const {
  2076   klassOop k = as_klassOop();
  2077   jint access = access_flags().as_int();
  2079   // But check if it happens to be member class.
  2080   typeArrayOop inner_class_list = inner_classes();
  2081   int length = (inner_class_list == NULL) ? 0 : inner_class_list->length();
  2082   assert (length % instanceKlass::inner_class_next_offset == 0, "just checking");
  2083   if (length > 0) {
  2084     typeArrayHandle inner_class_list_h(THREAD, inner_class_list);
  2085     instanceKlassHandle ik(THREAD, k);
  2086     for (int i = 0; i < length; i += instanceKlass::inner_class_next_offset) {
  2087       int ioff = inner_class_list_h->ushort_at(
  2088                       i + instanceKlass::inner_class_inner_class_info_offset);
  2090       // Inner class attribute can be zero, skip it.
  2091       // Strange but true:  JVM spec. allows null inner class refs.
  2092       if (ioff == 0) continue;
  2094       // only look at classes that are already loaded
  2095       // since we are looking for the flags for our self.
  2096       symbolOop inner_name = ik->constants()->klass_name_at(ioff);
  2097       if ((ik->name() == inner_name)) {
  2098         // This is really a member class.
  2099         access = inner_class_list_h->ushort_at(i + instanceKlass::inner_class_access_flags_offset);
  2100         break;
  2104   // Remember to strip ACC_SUPER bit
  2105   return (access & (~JVM_ACC_SUPER)) & JVM_ACC_WRITTEN_FLAGS;
  2108 jint instanceKlass::jvmti_class_status() const {
  2109   jint result = 0;
  2111   if (is_linked()) {
  2112     result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED;
  2115   if (is_initialized()) {
  2116     assert(is_linked(), "Class status is not consistent");
  2117     result |= JVMTI_CLASS_STATUS_INITIALIZED;
  2119   if (is_in_error_state()) {
  2120     result |= JVMTI_CLASS_STATUS_ERROR;
  2122   return result;
  2125 methodOop instanceKlass::method_at_itable(klassOop holder, int index, TRAPS) {
  2126   itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
  2127   int method_table_offset_in_words = ioe->offset()/wordSize;
  2128   int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words())
  2129                        / itableOffsetEntry::size();
  2131   for (int cnt = 0 ; ; cnt ++, ioe ++) {
  2132     // If the interface isn't implemented by the receiver class,
  2133     // the VM should throw IncompatibleClassChangeError.
  2134     if (cnt >= nof_interfaces) {
  2135       THROW_OOP_0(vmSymbols::java_lang_IncompatibleClassChangeError());
  2138     klassOop ik = ioe->interface_klass();
  2139     if (ik == holder) break;
  2142   itableMethodEntry* ime = ioe->first_method_entry(as_klassOop());
  2143   methodOop m = ime[index].method();
  2144   if (m == NULL) {
  2145     THROW_OOP_0(vmSymbols::java_lang_AbstractMethodError());
  2147   return m;
  2150 // On-stack replacement stuff
  2151 void instanceKlass::add_osr_nmethod(nmethod* n) {
  2152   // only one compilation can be active
  2153   NEEDS_CLEANUP
  2154   // This is a short non-blocking critical region, so the no safepoint check is ok.
  2155   OsrList_lock->lock_without_safepoint_check();
  2156   assert(n->is_osr_method(), "wrong kind of nmethod");
  2157   n->set_osr_link(osr_nmethods_head());
  2158   set_osr_nmethods_head(n);
  2159   // Remember to unlock again
  2160   OsrList_lock->unlock();
  2164 void instanceKlass::remove_osr_nmethod(nmethod* n) {
  2165   // This is a short non-blocking critical region, so the no safepoint check is ok.
  2166   OsrList_lock->lock_without_safepoint_check();
  2167   assert(n->is_osr_method(), "wrong kind of nmethod");
  2168   nmethod* last = NULL;
  2169   nmethod* cur  = osr_nmethods_head();
  2170   // Search for match
  2171   while(cur != NULL && cur != n) {
  2172     last = cur;
  2173     cur = cur->osr_link();
  2175   if (cur == n) {
  2176     if (last == NULL) {
  2177       // Remove first element
  2178       set_osr_nmethods_head(osr_nmethods_head()->osr_link());
  2179     } else {
  2180       last->set_osr_link(cur->osr_link());
  2183   n->set_osr_link(NULL);
  2184   // Remember to unlock again
  2185   OsrList_lock->unlock();
  2188 nmethod* instanceKlass::lookup_osr_nmethod(const methodOop m, int bci) const {
  2189   // This is a short non-blocking critical region, so the no safepoint check is ok.
  2190   OsrList_lock->lock_without_safepoint_check();
  2191   nmethod* osr = osr_nmethods_head();
  2192   while (osr != NULL) {
  2193     assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
  2194     if (osr->method() == m &&
  2195         (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) {
  2196       // Found a match - return it.
  2197       OsrList_lock->unlock();
  2198       return osr;
  2200     osr = osr->osr_link();
  2202   OsrList_lock->unlock();
  2203   return NULL;
  2206 // -----------------------------------------------------------------------------------------------------
  2207 #ifndef PRODUCT
  2209 // Printing
  2211 #define BULLET  " - "
  2213 void FieldPrinter::do_field(fieldDescriptor* fd) {
  2214   _st->print(BULLET);
  2215    if (fd->is_static() || (_obj == NULL)) {
  2216      fd->print_on(_st);
  2217      _st->cr();
  2218    } else {
  2219      fd->print_on_for(_st, _obj);
  2220      _st->cr();
  2225 void instanceKlass::oop_print_on(oop obj, outputStream* st) {
  2226   Klass::oop_print_on(obj, st);
  2228   if (as_klassOop() == SystemDictionary::String_klass()) {
  2229     typeArrayOop value  = java_lang_String::value(obj);
  2230     juint        offset = java_lang_String::offset(obj);
  2231     juint        length = java_lang_String::length(obj);
  2232     if (value != NULL &&
  2233         value->is_typeArray() &&
  2234         offset          <= (juint) value->length() &&
  2235         offset + length <= (juint) value->length()) {
  2236       st->print(BULLET"string: ");
  2237       Handle h_obj(obj);
  2238       java_lang_String::print(h_obj, st);
  2239       st->cr();
  2240       if (!WizardMode)  return;  // that is enough
  2244   st->print_cr(BULLET"---- fields (total size %d words):", oop_size(obj));
  2245   FieldPrinter print_nonstatic_field(st, obj);
  2246   do_nonstatic_fields(&print_nonstatic_field);
  2248   if (as_klassOop() == SystemDictionary::Class_klass()) {
  2249     st->print(BULLET"signature: ");
  2250     java_lang_Class::print_signature(obj, st);
  2251     st->cr();
  2252     klassOop mirrored_klass = java_lang_Class::as_klassOop(obj);
  2253     st->print(BULLET"fake entry for mirror: ");
  2254     mirrored_klass->print_value_on(st);
  2255     st->cr();
  2256     st->print(BULLET"fake entry resolved_constructor: ");
  2257     methodOop ctor = java_lang_Class::resolved_constructor(obj);
  2258     ctor->print_value_on(st);
  2259     klassOop array_klass = java_lang_Class::array_klass(obj);
  2260     st->cr();
  2261     st->print(BULLET"fake entry for array: ");
  2262     array_klass->print_value_on(st);
  2263     st->cr();
  2264   } else if (as_klassOop() == SystemDictionary::MethodType_klass()) {
  2265     st->print(BULLET"signature: ");
  2266     java_dyn_MethodType::print_signature(obj, st);
  2267     st->cr();
  2271 #endif //PRODUCT
  2273 void instanceKlass::oop_print_value_on(oop obj, outputStream* st) {
  2274   st->print("a ");
  2275   name()->print_value_on(st);
  2276   obj->print_address_on(st);
  2277   if (as_klassOop() == SystemDictionary::String_klass()
  2278       && java_lang_String::value(obj) != NULL) {
  2279     ResourceMark rm;
  2280     int len = java_lang_String::length(obj);
  2281     int plen = (len < 24 ? len : 12);
  2282     char* str = java_lang_String::as_utf8_string(obj, 0, plen);
  2283     st->print(" = \"%s\"", str);
  2284     if (len > plen)
  2285       st->print("...[%d]", len);
  2286   } else if (as_klassOop() == SystemDictionary::Class_klass()) {
  2287     klassOop k = java_lang_Class::as_klassOop(obj);
  2288     st->print(" = ");
  2289     if (k != NULL) {
  2290       k->print_value_on(st);
  2291     } else {
  2292       const char* tname = type2name(java_lang_Class::primitive_type(obj));
  2293       st->print("%s", tname ? tname : "type?");
  2295   } else if (as_klassOop() == SystemDictionary::MethodType_klass()) {
  2296     st->print(" = ");
  2297     java_dyn_MethodType::print_signature(obj, st);
  2298   } else if (java_lang_boxing_object::is_instance(obj)) {
  2299     st->print(" = ");
  2300     java_lang_boxing_object::print(obj, st);
  2304 const char* instanceKlass::internal_name() const {
  2305   return external_name();
  2308 // Verification
  2310 class VerifyFieldClosure: public OopClosure {
  2311  protected:
  2312   template <class T> void do_oop_work(T* p) {
  2313     guarantee(Universe::heap()->is_in_closed_subset(p), "should be in heap");
  2314     oop obj = oopDesc::load_decode_heap_oop(p);
  2315     if (!obj->is_oop_or_null()) {
  2316       tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p, (address)obj);
  2317       Universe::print();
  2318       guarantee(false, "boom");
  2321  public:
  2322   virtual void do_oop(oop* p)       { VerifyFieldClosure::do_oop_work(p); }
  2323   virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); }
  2324 };
  2326 void instanceKlass::oop_verify_on(oop obj, outputStream* st) {
  2327   Klass::oop_verify_on(obj, st);
  2328   VerifyFieldClosure blk;
  2329   oop_oop_iterate(obj, &blk);
  2332 #ifndef PRODUCT
  2334 void instanceKlass::verify_class_klass_nonstatic_oop_maps(klassOop k) {
  2335   // This verification code is disabled.  JDK_Version::is_gte_jdk14x_version()
  2336   // cannot be called since this function is called before the VM is
  2337   // able to determine what JDK version is running with.
  2338   // The check below always is false since 1.4.
  2339   return;
  2341   // This verification code temporarily disabled for the 1.4
  2342   // reflection implementation since java.lang.Class now has
  2343   // Java-level instance fields. Should rewrite this to handle this
  2344   // case.
  2345   if (!(JDK_Version::is_gte_jdk14x_version() && UseNewReflection)) {
  2346     // Verify that java.lang.Class instances have a fake oop field added.
  2347     instanceKlass* ik = instanceKlass::cast(k);
  2349     // Check that we have the right class
  2350     static bool first_time = true;
  2351     guarantee(k == SystemDictionary::Class_klass() && first_time, "Invalid verify of maps");
  2352     first_time = false;
  2353     const int extra = java_lang_Class::number_of_fake_oop_fields;
  2354     guarantee(ik->nonstatic_field_size() == extra, "just checking");
  2355     guarantee(ik->nonstatic_oop_map_count() == 1, "just checking");
  2356     guarantee(ik->size_helper() == align_object_size(instanceOopDesc::header_size() + extra), "just checking");
  2358     // Check that the map is (2,extra)
  2359     int offset = java_lang_Class::klass_offset;
  2361     OopMapBlock* map = ik->start_of_nonstatic_oop_maps();
  2362     guarantee(map->offset() == offset && map->count() == (unsigned int) extra,
  2363               "sanity");
  2367 #endif // ndef PRODUCT
  2369 // JNIid class for jfieldIDs only
  2370 // Note to reviewers:
  2371 // These JNI functions are just moved over to column 1 and not changed
  2372 // in the compressed oops workspace.
  2373 JNIid::JNIid(klassOop holder, int offset, JNIid* next) {
  2374   _holder = holder;
  2375   _offset = offset;
  2376   _next = next;
  2377   debug_only(_is_static_field_id = false;)
  2381 JNIid* JNIid::find(int offset) {
  2382   JNIid* current = this;
  2383   while (current != NULL) {
  2384     if (current->offset() == offset) return current;
  2385     current = current->next();
  2387   return NULL;
  2390 void JNIid::oops_do(OopClosure* f) {
  2391   for (JNIid* cur = this; cur != NULL; cur = cur->next()) {
  2392     f->do_oop(cur->holder_addr());
  2396 void JNIid::deallocate(JNIid* current) {
  2397   while (current != NULL) {
  2398     JNIid* next = current->next();
  2399     delete current;
  2400     current = next;
  2405 void JNIid::verify(klassOop holder) {
  2406   int first_field_offset  = instanceKlass::cast(holder)->offset_of_static_fields();
  2407   int end_field_offset;
  2408   end_field_offset = first_field_offset + (instanceKlass::cast(holder)->static_field_size() * wordSize);
  2410   JNIid* current = this;
  2411   while (current != NULL) {
  2412     guarantee(current->holder() == holder, "Invalid klass in JNIid");
  2413 #ifdef ASSERT
  2414     int o = current->offset();
  2415     if (current->is_static_field_id()) {
  2416       guarantee(o >= first_field_offset  && o < end_field_offset,  "Invalid static field offset in JNIid");
  2418 #endif
  2419     current = current->next();
  2424 #ifdef ASSERT
  2425 void instanceKlass::set_init_state(ClassState state) {
  2426   bool good_state = as_klassOop()->is_shared() ? (_init_state <= state)
  2427                                                : (_init_state < state);
  2428   assert(good_state || state == allocated, "illegal state transition");
  2429   _init_state = state;
  2431 #endif
  2434 // RedefineClasses() support for previous versions:
  2436 // Add an information node that contains weak references to the
  2437 // interesting parts of the previous version of the_class.
  2438 // This is also where we clean out any unused weak references.
  2439 // Note that while we delete nodes from the _previous_versions
  2440 // array, we never delete the array itself until the klass is
  2441 // unloaded. The has_been_redefined() query depends on that fact.
  2442 //
  2443 void instanceKlass::add_previous_version(instanceKlassHandle ikh,
  2444        BitMap* emcp_methods, int emcp_method_count) {
  2445   assert(Thread::current()->is_VM_thread(),
  2446          "only VMThread can add previous versions");
  2448   if (_previous_versions == NULL) {
  2449     // This is the first previous version so make some space.
  2450     // Start with 2 elements under the assumption that the class
  2451     // won't be redefined much.
  2452     _previous_versions =  new (ResourceObj::C_HEAP)
  2453                             GrowableArray<PreviousVersionNode *>(2, true);
  2456   // RC_TRACE macro has an embedded ResourceMark
  2457   RC_TRACE(0x00000100, ("adding previous version ref for %s @%d, EMCP_cnt=%d",
  2458     ikh->external_name(), _previous_versions->length(), emcp_method_count));
  2459   constantPoolHandle cp_h(ikh->constants());
  2460   jobject cp_ref;
  2461   if (cp_h->is_shared()) {
  2462     // a shared ConstantPool requires a regular reference; a weak
  2463     // reference would be collectible
  2464     cp_ref = JNIHandles::make_global(cp_h);
  2465   } else {
  2466     cp_ref = JNIHandles::make_weak_global(cp_h);
  2468   PreviousVersionNode * pv_node = NULL;
  2469   objArrayOop old_methods = ikh->methods();
  2471   if (emcp_method_count == 0) {
  2472     // non-shared ConstantPool gets a weak reference
  2473     pv_node = new PreviousVersionNode(cp_ref, !cp_h->is_shared(), NULL);
  2474     RC_TRACE(0x00000400,
  2475       ("add: all methods are obsolete; flushing any EMCP weak refs"));
  2476   } else {
  2477     int local_count = 0;
  2478     GrowableArray<jweak>* method_refs = new (ResourceObj::C_HEAP)
  2479       GrowableArray<jweak>(emcp_method_count, true);
  2480     for (int i = 0; i < old_methods->length(); i++) {
  2481       if (emcp_methods->at(i)) {
  2482         // this old method is EMCP so save a weak ref
  2483         methodOop old_method = (methodOop) old_methods->obj_at(i);
  2484         methodHandle old_method_h(old_method);
  2485         jweak method_ref = JNIHandles::make_weak_global(old_method_h);
  2486         method_refs->append(method_ref);
  2487         if (++local_count >= emcp_method_count) {
  2488           // no more EMCP methods so bail out now
  2489           break;
  2493     // non-shared ConstantPool gets a weak reference
  2494     pv_node = new PreviousVersionNode(cp_ref, !cp_h->is_shared(), method_refs);
  2497   _previous_versions->append(pv_node);
  2499   // Using weak references allows the interesting parts of previous
  2500   // classes to be GC'ed when they are no longer needed. Since the
  2501   // caller is the VMThread and we are at a safepoint, this is a good
  2502   // time to clear out unused weak references.
  2504   RC_TRACE(0x00000400, ("add: previous version length=%d",
  2505     _previous_versions->length()));
  2507   // skip the last entry since we just added it
  2508   for (int i = _previous_versions->length() - 2; i >= 0; i--) {
  2509     // check the previous versions array for a GC'ed weak refs
  2510     pv_node = _previous_versions->at(i);
  2511     cp_ref = pv_node->prev_constant_pool();
  2512     assert(cp_ref != NULL, "cp ref was unexpectedly cleared");
  2513     if (cp_ref == NULL) {
  2514       delete pv_node;
  2515       _previous_versions->remove_at(i);
  2516       // Since we are traversing the array backwards, we don't have to
  2517       // do anything special with the index.
  2518       continue;  // robustness
  2521     constantPoolOop cp = (constantPoolOop)JNIHandles::resolve(cp_ref);
  2522     if (cp == NULL) {
  2523       // this entry has been GC'ed so remove it
  2524       delete pv_node;
  2525       _previous_versions->remove_at(i);
  2526       // Since we are traversing the array backwards, we don't have to
  2527       // do anything special with the index.
  2528       continue;
  2529     } else {
  2530       RC_TRACE(0x00000400, ("add: previous version @%d is alive", i));
  2533     GrowableArray<jweak>* method_refs = pv_node->prev_EMCP_methods();
  2534     if (method_refs != NULL) {
  2535       RC_TRACE(0x00000400, ("add: previous methods length=%d",
  2536         method_refs->length()));
  2537       for (int j = method_refs->length() - 1; j >= 0; j--) {
  2538         jweak method_ref = method_refs->at(j);
  2539         assert(method_ref != NULL, "weak method ref was unexpectedly cleared");
  2540         if (method_ref == NULL) {
  2541           method_refs->remove_at(j);
  2542           // Since we are traversing the array backwards, we don't have to
  2543           // do anything special with the index.
  2544           continue;  // robustness
  2547         methodOop method = (methodOop)JNIHandles::resolve(method_ref);
  2548         if (method == NULL || emcp_method_count == 0) {
  2549           // This method entry has been GC'ed or the current
  2550           // RedefineClasses() call has made all methods obsolete
  2551           // so remove it.
  2552           JNIHandles::destroy_weak_global(method_ref);
  2553           method_refs->remove_at(j);
  2554         } else {
  2555           // RC_TRACE macro has an embedded ResourceMark
  2556           RC_TRACE(0x00000400,
  2557             ("add: %s(%s): previous method @%d in version @%d is alive",
  2558             method->name()->as_C_string(), method->signature()->as_C_string(),
  2559             j, i));
  2565   int obsolete_method_count = old_methods->length() - emcp_method_count;
  2567   if (emcp_method_count != 0 && obsolete_method_count != 0 &&
  2568       _previous_versions->length() > 1) {
  2569     // We have a mix of obsolete and EMCP methods. If there is more
  2570     // than the previous version that we just added, then we have to
  2571     // clear out any matching EMCP method entries the hard way.
  2572     int local_count = 0;
  2573     for (int i = 0; i < old_methods->length(); i++) {
  2574       if (!emcp_methods->at(i)) {
  2575         // only obsolete methods are interesting
  2576         methodOop old_method = (methodOop) old_methods->obj_at(i);
  2577         symbolOop m_name = old_method->name();
  2578         symbolOop m_signature = old_method->signature();
  2580         // skip the last entry since we just added it
  2581         for (int j = _previous_versions->length() - 2; j >= 0; j--) {
  2582           // check the previous versions array for a GC'ed weak refs
  2583           pv_node = _previous_versions->at(j);
  2584           cp_ref = pv_node->prev_constant_pool();
  2585           assert(cp_ref != NULL, "cp ref was unexpectedly cleared");
  2586           if (cp_ref == NULL) {
  2587             delete pv_node;
  2588             _previous_versions->remove_at(j);
  2589             // Since we are traversing the array backwards, we don't have to
  2590             // do anything special with the index.
  2591             continue;  // robustness
  2594           constantPoolOop cp = (constantPoolOop)JNIHandles::resolve(cp_ref);
  2595           if (cp == NULL) {
  2596             // this entry has been GC'ed so remove it
  2597             delete pv_node;
  2598             _previous_versions->remove_at(j);
  2599             // Since we are traversing the array backwards, we don't have to
  2600             // do anything special with the index.
  2601             continue;
  2604           GrowableArray<jweak>* method_refs = pv_node->prev_EMCP_methods();
  2605           if (method_refs == NULL) {
  2606             // We have run into a PreviousVersion generation where
  2607             // all methods were made obsolete during that generation's
  2608             // RedefineClasses() operation. At the time of that
  2609             // operation, all EMCP methods were flushed so we don't
  2610             // have to go back any further.
  2611             //
  2612             // A NULL method_refs is different than an empty method_refs.
  2613             // We cannot infer any optimizations about older generations
  2614             // from an empty method_refs for the current generation.
  2615             break;
  2618           for (int k = method_refs->length() - 1; k >= 0; k--) {
  2619             jweak method_ref = method_refs->at(k);
  2620             assert(method_ref != NULL,
  2621               "weak method ref was unexpectedly cleared");
  2622             if (method_ref == NULL) {
  2623               method_refs->remove_at(k);
  2624               // Since we are traversing the array backwards, we don't
  2625               // have to do anything special with the index.
  2626               continue;  // robustness
  2629             methodOop method = (methodOop)JNIHandles::resolve(method_ref);
  2630             if (method == NULL) {
  2631               // this method entry has been GC'ed so skip it
  2632               JNIHandles::destroy_weak_global(method_ref);
  2633               method_refs->remove_at(k);
  2634               continue;
  2637             if (method->name() == m_name &&
  2638                 method->signature() == m_signature) {
  2639               // The current RedefineClasses() call has made all EMCP
  2640               // versions of this method obsolete so mark it as obsolete
  2641               // and remove the weak ref.
  2642               RC_TRACE(0x00000400,
  2643                 ("add: %s(%s): flush obsolete method @%d in version @%d",
  2644                 m_name->as_C_string(), m_signature->as_C_string(), k, j));
  2646               method->set_is_obsolete();
  2647               JNIHandles::destroy_weak_global(method_ref);
  2648               method_refs->remove_at(k);
  2649               break;
  2653           // The previous loop may not find a matching EMCP method, but
  2654           // that doesn't mean that we can optimize and not go any
  2655           // further back in the PreviousVersion generations. The EMCP
  2656           // method for this generation could have already been GC'ed,
  2657           // but there still may be an older EMCP method that has not
  2658           // been GC'ed.
  2661         if (++local_count >= obsolete_method_count) {
  2662           // no more obsolete methods so bail out now
  2663           break;
  2668 } // end add_previous_version()
  2671 // Determine if instanceKlass has a previous version.
  2672 bool instanceKlass::has_previous_version() const {
  2673   if (_previous_versions == NULL) {
  2674     // no previous versions array so answer is easy
  2675     return false;
  2678   for (int i = _previous_versions->length() - 1; i >= 0; i--) {
  2679     // Check the previous versions array for an info node that hasn't
  2680     // been GC'ed
  2681     PreviousVersionNode * pv_node = _previous_versions->at(i);
  2683     jobject cp_ref = pv_node->prev_constant_pool();
  2684     assert(cp_ref != NULL, "cp reference was unexpectedly cleared");
  2685     if (cp_ref == NULL) {
  2686       continue;  // robustness
  2689     constantPoolOop cp = (constantPoolOop)JNIHandles::resolve(cp_ref);
  2690     if (cp != NULL) {
  2691       // we have at least one previous version
  2692       return true;
  2695     // We don't have to check the method refs. If the constant pool has
  2696     // been GC'ed then so have the methods.
  2699   // all of the underlying nodes' info has been GC'ed
  2700   return false;
  2701 } // end has_previous_version()
  2703 methodOop instanceKlass::method_with_idnum(int idnum) {
  2704   methodOop m = NULL;
  2705   if (idnum < methods()->length()) {
  2706     m = (methodOop) methods()->obj_at(idnum);
  2708   if (m == NULL || m->method_idnum() != idnum) {
  2709     for (int index = 0; index < methods()->length(); ++index) {
  2710       m = (methodOop) methods()->obj_at(index);
  2711       if (m->method_idnum() == idnum) {
  2712         return m;
  2716   return m;
  2720 // Set the annotation at 'idnum' to 'anno'.
  2721 // We don't want to create or extend the array if 'anno' is NULL, since that is the
  2722 // default value.  However, if the array exists and is long enough, we must set NULL values.
  2723 void instanceKlass::set_methods_annotations_of(int idnum, typeArrayOop anno, objArrayOop* md_p) {
  2724   objArrayOop md = *md_p;
  2725   if (md != NULL && md->length() > idnum) {
  2726     md->obj_at_put(idnum, anno);
  2727   } else if (anno != NULL) {
  2728     // create the array
  2729     int length = MAX2(idnum+1, (int)_idnum_allocated_count);
  2730     md = oopFactory::new_system_objArray(length, Thread::current());
  2731     if (*md_p != NULL) {
  2732       // copy the existing entries
  2733       for (int index = 0; index < (*md_p)->length(); index++) {
  2734         md->obj_at_put(index, (*md_p)->obj_at(index));
  2737     set_annotations(md, md_p);
  2738     md->obj_at_put(idnum, anno);
  2739   } // if no array and idnum isn't included there is nothing to do
  2742 // Construct a PreviousVersionNode entry for the array hung off
  2743 // the instanceKlass.
  2744 PreviousVersionNode::PreviousVersionNode(jobject prev_constant_pool,
  2745   bool prev_cp_is_weak, GrowableArray<jweak>* prev_EMCP_methods) {
  2747   _prev_constant_pool = prev_constant_pool;
  2748   _prev_cp_is_weak = prev_cp_is_weak;
  2749   _prev_EMCP_methods = prev_EMCP_methods;
  2753 // Destroy a PreviousVersionNode
  2754 PreviousVersionNode::~PreviousVersionNode() {
  2755   if (_prev_constant_pool != NULL) {
  2756     if (_prev_cp_is_weak) {
  2757       JNIHandles::destroy_weak_global(_prev_constant_pool);
  2758     } else {
  2759       JNIHandles::destroy_global(_prev_constant_pool);
  2763   if (_prev_EMCP_methods != NULL) {
  2764     for (int i = _prev_EMCP_methods->length() - 1; i >= 0; i--) {
  2765       jweak method_ref = _prev_EMCP_methods->at(i);
  2766       if (method_ref != NULL) {
  2767         JNIHandles::destroy_weak_global(method_ref);
  2770     delete _prev_EMCP_methods;
  2775 // Construct a PreviousVersionInfo entry
  2776 PreviousVersionInfo::PreviousVersionInfo(PreviousVersionNode *pv_node) {
  2777   _prev_constant_pool_handle = constantPoolHandle();  // NULL handle
  2778   _prev_EMCP_method_handles = NULL;
  2780   jobject cp_ref = pv_node->prev_constant_pool();
  2781   assert(cp_ref != NULL, "constant pool ref was unexpectedly cleared");
  2782   if (cp_ref == NULL) {
  2783     return;  // robustness
  2786   constantPoolOop cp = (constantPoolOop)JNIHandles::resolve(cp_ref);
  2787   if (cp == NULL) {
  2788     // Weak reference has been GC'ed. Since the constant pool has been
  2789     // GC'ed, the methods have also been GC'ed.
  2790     return;
  2793   // make the constantPoolOop safe to return
  2794   _prev_constant_pool_handle = constantPoolHandle(cp);
  2796   GrowableArray<jweak>* method_refs = pv_node->prev_EMCP_methods();
  2797   if (method_refs == NULL) {
  2798     // the instanceKlass did not have any EMCP methods
  2799     return;
  2802   _prev_EMCP_method_handles = new GrowableArray<methodHandle>(10);
  2804   int n_methods = method_refs->length();
  2805   for (int i = 0; i < n_methods; i++) {
  2806     jweak method_ref = method_refs->at(i);
  2807     assert(method_ref != NULL, "weak method ref was unexpectedly cleared");
  2808     if (method_ref == NULL) {
  2809       continue;  // robustness
  2812     methodOop method = (methodOop)JNIHandles::resolve(method_ref);
  2813     if (method == NULL) {
  2814       // this entry has been GC'ed so skip it
  2815       continue;
  2818     // make the methodOop safe to return
  2819     _prev_EMCP_method_handles->append(methodHandle(method));
  2824 // Destroy a PreviousVersionInfo
  2825 PreviousVersionInfo::~PreviousVersionInfo() {
  2826   // Since _prev_EMCP_method_handles is not C-heap allocated, we
  2827   // don't have to delete it.
  2831 // Construct a helper for walking the previous versions array
  2832 PreviousVersionWalker::PreviousVersionWalker(instanceKlass *ik) {
  2833   _previous_versions = ik->previous_versions();
  2834   _current_index = 0;
  2835   // _hm needs no initialization
  2836   _current_p = NULL;
  2840 // Destroy a PreviousVersionWalker
  2841 PreviousVersionWalker::~PreviousVersionWalker() {
  2842   // Delete the current info just in case the caller didn't walk to
  2843   // the end of the previous versions list. No harm if _current_p is
  2844   // already NULL.
  2845   delete _current_p;
  2847   // When _hm is destroyed, all the Handles returned in
  2848   // PreviousVersionInfo objects will be destroyed.
  2849   // Also, after this destructor is finished it will be
  2850   // safe to delete the GrowableArray allocated in the
  2851   // PreviousVersionInfo objects.
  2855 // Return the interesting information for the next previous version
  2856 // of the klass. Returns NULL if there are no more previous versions.
  2857 PreviousVersionInfo* PreviousVersionWalker::next_previous_version() {
  2858   if (_previous_versions == NULL) {
  2859     // no previous versions so nothing to return
  2860     return NULL;
  2863   delete _current_p;  // cleanup the previous info for the caller
  2864   _current_p = NULL;  // reset to NULL so we don't delete same object twice
  2866   int length = _previous_versions->length();
  2868   while (_current_index < length) {
  2869     PreviousVersionNode * pv_node = _previous_versions->at(_current_index++);
  2870     PreviousVersionInfo * pv_info = new (ResourceObj::C_HEAP)
  2871                                           PreviousVersionInfo(pv_node);
  2873     constantPoolHandle cp_h = pv_info->prev_constant_pool_handle();
  2874     if (cp_h.is_null()) {
  2875       delete pv_info;
  2877       // The underlying node's info has been GC'ed so try the next one.
  2878       // We don't have to check the methods. If the constant pool has
  2879       // GC'ed then so have the methods.
  2880       continue;
  2883     // Found a node with non GC'ed info so return it. The caller will
  2884     // need to delete pv_info when they are done with it.
  2885     _current_p = pv_info;
  2886     return pv_info;
  2889   // all of the underlying nodes' info has been GC'ed
  2890   return NULL;
  2891 } // end next_previous_version()

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