jdk8-mips64-public/hotspot: src/share/vm/oops/instanceKlass.cpp@8033953d67ff (annotated)

src/share/vm/oops/instanceKlass.cpp@8033953d67ff (annotated)

src/share/vm/oops/instanceKlass.cpp

Fri, 11 Mar 2011 22:34:57 -0800

author: jrose
date: Fri, 11 Mar 2011 22:34:57 -0800
changeset 2639: 8033953d67ff
parent 2616: dbad0519a1c4
child 2658: c7f3d0b4570f
permissions: -rw-r--r--

7012648: move JSR 292 to package java.lang.invoke and adjust names
Summary: package and class renaming only; delete unused methods and classes
Reviewed-by: twisti

 /*
  * Copyright (c) 1997, 2011, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
  * under the terms of the GNU General Public License version 2 only, as
  * published by the Free Software Foundation.
  *
  * This code is distributed in the hope that it will be useful, but WITHOUT
  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  * version 2 for more details (a copy is included in the LICENSE file that
  * accompanied this code).
  *
  * You should have received a copy of the GNU General Public License version
  * 2 along with this work; if not, write to the Free Software Foundation,
  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  *
  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  * or visit www.oracle.com if you need additional information or have any
  * questions.
  *
  */
 #include "precompiled.hpp"
 #include "classfile/javaClasses.hpp"
 #include "classfile/systemDictionary.hpp"
 #include "classfile/verifier.hpp"
 #include "classfile/vmSymbols.hpp"
 #include "compiler/compileBroker.hpp"
 #include "gc_implementation/shared/markSweep.inline.hpp"
 #include "gc_interface/collectedHeap.inline.hpp"
 #include "interpreter/oopMapCache.hpp"
 #include "interpreter/rewriter.hpp"
 #include "jvmtifiles/jvmti.h"
 #include "memory/genOopClosures.inline.hpp"
 #include "memory/oopFactory.hpp"
 #include "memory/permGen.hpp"
 #include "oops/instanceKlass.hpp"
 #include "oops/instanceOop.hpp"
 #include "oops/methodOop.hpp"
 #include "oops/objArrayKlassKlass.hpp"
 #include "oops/oop.inline.hpp"
 #include "oops/symbol.hpp"
 #include "prims/jvmtiExport.hpp"
 #include "prims/jvmtiRedefineClassesTrace.hpp"
 #include "runtime/fieldDescriptor.hpp"
 #include "runtime/handles.inline.hpp"
 #include "runtime/javaCalls.hpp"
 #include "runtime/mutexLocker.hpp"
 #include "services/threadService.hpp"
 #include "utilities/dtrace.hpp"
 #ifdef TARGET_OS_FAMILY_linux
 # include "thread_linux.inline.hpp"
 #endif
 #ifdef TARGET_OS_FAMILY_solaris
 # include "thread_solaris.inline.hpp"
 #endif
 #ifdef TARGET_OS_FAMILY_windows
 # include "thread_windows.inline.hpp"
 #endif
 #ifndef SERIALGC
 #include "gc_implementation/g1/g1CollectedHeap.inline.hpp"
 #include "gc_implementation/g1/g1OopClosures.inline.hpp"
 #include "gc_implementation/g1/g1RemSet.inline.hpp"
 #include "gc_implementation/g1/heapRegionSeq.inline.hpp"
 #include "gc_implementation/parNew/parOopClosures.inline.hpp"
 #include "gc_implementation/parallelScavenge/psPromotionManager.inline.hpp"
 #include "gc_implementation/parallelScavenge/psScavenge.inline.hpp"
 #include "oops/oop.pcgc.inline.hpp"
 #endif
 #ifdef COMPILER1
 #include "c1/c1_Compiler.hpp"
 #endif
 #ifdef DTRACE_ENABLED
 HS_DTRACE_PROBE_DECL4(hotspot, class__initialization__required,
   char*, intptr_t, oop, intptr_t);
 HS_DTRACE_PROBE_DECL5(hotspot, class__initialization__recursive,
   char*, intptr_t, oop, intptr_t, int);
 HS_DTRACE_PROBE_DECL5(hotspot, class__initialization__concurrent,
   char*, intptr_t, oop, intptr_t, int);
 HS_DTRACE_PROBE_DECL5(hotspot, class__initialization__erroneous,
   char*, intptr_t, oop, intptr_t, int);
 HS_DTRACE_PROBE_DECL5(hotspot, class__initialization__super__failed,
   char*, intptr_t, oop, intptr_t, int);
 HS_DTRACE_PROBE_DECL5(hotspot, class__initialization__clinit,
   char*, intptr_t, oop, intptr_t, int);
 HS_DTRACE_PROBE_DECL5(hotspot, class__initialization__error,
   char*, intptr_t, oop, intptr_t, int);
 HS_DTRACE_PROBE_DECL5(hotspot, class__initialization__end,
   char*, intptr_t, oop, intptr_t, int);
 #define DTRACE_CLASSINIT_PROBE(type, clss, thread_type)          \
   {                                                              \
     char* data = NULL;                                           \
     int len = 0;                                                 \
     Symbol* name = (clss)->name();                               \
     if (name != NULL) {                                          \
       data = (char*)name->bytes();                               \
       len = name->utf8_length();                                 \
     }                                                            \
     HS_DTRACE_PROBE4(hotspot, class__initialization__##type,     \
       data, len, (clss)->class_loader(), thread_type);           \
   }
 #define DTRACE_CLASSINIT_PROBE_WAIT(type, clss, thread_type, wait) \
   {                                                              \
     char* data = NULL;                                           \
     int len = 0;                                                 \
     Symbol* name = (clss)->name();                               \
     if (name != NULL) {                                          \
       data = (char*)name->bytes();                               \
       len = name->utf8_length();                                 \
     }                                                            \
     HS_DTRACE_PROBE5(hotspot, class__initialization__##type,     \
       data, len, (clss)->class_loader(), thread_type, wait);     \
   }
 #else //  ndef DTRACE_ENABLED
 #define DTRACE_CLASSINIT_PROBE(type, clss, thread_type)
 #define DTRACE_CLASSINIT_PROBE_WAIT(type, clss, thread_type, wait)
 #endif //  ndef DTRACE_ENABLED
 bool instanceKlass::should_be_initialized() const {
   return !is_initialized();
 }
 klassVtable* instanceKlass::vtable() const {
   return new klassVtable(as_klassOop(), start_of_vtable(), vtable_length() / vtableEntry::size());
 }
 klassItable* instanceKlass::itable() const {
   return new klassItable(as_klassOop());
 }
 void instanceKlass::eager_initialize(Thread *thread) {
   if (!EagerInitialization) return;
   if (this->is_not_initialized()) {
     // abort if the the class has a class initializer
     if (this->class_initializer() != NULL) return;
     // abort if it is java.lang.Object (initialization is handled in genesis)
     klassOop super = this->super();
     if (super == NULL) return;
     // abort if the super class should be initialized
     if (!instanceKlass::cast(super)->is_initialized()) return;
     // call body to expose the this pointer
     instanceKlassHandle this_oop(thread, this->as_klassOop());
     eager_initialize_impl(this_oop);
   }
 }
 void instanceKlass::eager_initialize_impl(instanceKlassHandle this_oop) {
   EXCEPTION_MARK;
   ObjectLocker ol(this_oop, THREAD);
   // abort if someone beat us to the initialization
   if (!this_oop->is_not_initialized()) return;  // note: not equivalent to is_initialized()
   ClassState old_state = this_oop->_init_state;
   link_class_impl(this_oop, true, THREAD);
   if (HAS_PENDING_EXCEPTION) {
     CLEAR_PENDING_EXCEPTION;
     // Abort if linking the class throws an exception.
     // Use a test to avoid redundantly resetting the state if there's
     // no change.  Set_init_state() asserts that state changes make
     // progress, whereas here we might just be spinning in place.
     if( old_state != this_oop->_init_state )
       this_oop->set_init_state (old_state);
   } else {
     // linking successfull, mark class as initialized
     this_oop->set_init_state (fully_initialized);
     // trace
     if (TraceClassInitialization) {
       ResourceMark rm(THREAD);
       tty->print_cr("[Initialized %s without side effects]", this_oop->external_name());
     }
   }
 }
 // See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization
 // process. The step comments refers to the procedure described in that section.
 // Note: implementation moved to static method to expose the this pointer.
 void instanceKlass::initialize(TRAPS) {
   if (this->should_be_initialized()) {
     HandleMark hm(THREAD);
     instanceKlassHandle this_oop(THREAD, this->as_klassOop());
     initialize_impl(this_oop, CHECK);
     // Note: at this point the class may be initialized
     //       OR it may be in the state of being initialized
     //       in case of recursive initialization!
   } else {
     assert(is_initialized(), "sanity check");
   }
 }
 bool instanceKlass::verify_code(
     instanceKlassHandle this_oop, bool throw_verifyerror, TRAPS) {
   // 1) Verify the bytecodes
   Verifier::Mode mode =
     throw_verifyerror ? Verifier::ThrowException : Verifier::NoException;
   return Verifier::verify(this_oop, mode, this_oop->should_verify_class(), CHECK_false);
 }
 // Used exclusively by the shared spaces dump mechanism to prevent
 // classes mapped into the shared regions in new VMs from appearing linked.
 void instanceKlass::unlink_class() {
   assert(is_linked(), "must be linked");
   _init_state = loaded;
 }
 void instanceKlass::link_class(TRAPS) {
   assert(is_loaded(), "must be loaded");
   if (!is_linked()) {
     instanceKlassHandle this_oop(THREAD, this->as_klassOop());
     link_class_impl(this_oop, true, CHECK);
   }
 }
 // Called to verify that a class can link during initialization, without
 // throwing a VerifyError.
 bool instanceKlass::link_class_or_fail(TRAPS) {
   assert(is_loaded(), "must be loaded");
   if (!is_linked()) {
     instanceKlassHandle this_oop(THREAD, this->as_klassOop());
     link_class_impl(this_oop, false, CHECK_false);
   }
   return is_linked();
 }
 bool instanceKlass::link_class_impl(
     instanceKlassHandle this_oop, bool throw_verifyerror, TRAPS) {
   // check for error state
   if (this_oop->is_in_error_state()) {
     ResourceMark rm(THREAD);
     THROW_MSG_(vmSymbols::java_lang_NoClassDefFoundError(),
                this_oop->external_name(), false);
   }
   // return if already verified
   if (this_oop->is_linked()) {
     return true;
   }
   // Timing
   // timer handles recursion
   assert(THREAD->is_Java_thread(), "non-JavaThread in link_class_impl");
   JavaThread* jt = (JavaThread*)THREAD;
   // link super class before linking this class
   instanceKlassHandle super(THREAD, this_oop->super());
   if (super.not_null()) {
     if (super->is_interface()) {  // check if super class is an interface
       ResourceMark rm(THREAD);
       Exceptions::fthrow(
         THREAD_AND_LOCATION,
         vmSymbols::java_lang_IncompatibleClassChangeError(),
         "class %s has interface %s as super class",
         this_oop->external_name(),
         super->external_name()
       );
       return false;
     }
     link_class_impl(super, throw_verifyerror, CHECK_false);
   }
   // link all interfaces implemented by this class before linking this class
   objArrayHandle interfaces (THREAD, this_oop->local_interfaces());
   int num_interfaces = interfaces->length();
   for (int index = 0; index < num_interfaces; index++) {
     HandleMark hm(THREAD);
     instanceKlassHandle ih(THREAD, klassOop(interfaces->obj_at(index)));
     link_class_impl(ih, throw_verifyerror, CHECK_false);
   }
   // in case the class is linked in the process of linking its superclasses
   if (this_oop->is_linked()) {
     return true;
   }
   // trace only the link time for this klass that includes
   // the verification time
   PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(),
                              ClassLoader::perf_class_link_selftime(),
                              ClassLoader::perf_classes_linked(),
                              jt->get_thread_stat()->perf_recursion_counts_addr(),
                              jt->get_thread_stat()->perf_timers_addr(),
                              PerfClassTraceTime::CLASS_LINK);
   // verification & rewriting
   {
     ObjectLocker ol(this_oop, THREAD);
     // rewritten will have been set if loader constraint error found
     // on an earlier link attempt
     // don't verify or rewrite if already rewritten
     if (!this_oop->is_linked()) {
       if (!this_oop->is_rewritten()) {
         {
           // Timer includes any side effects of class verification (resolution,
           // etc), but not recursive entry into verify_code().
           PerfClassTraceTime timer(ClassLoader::perf_class_verify_time(),
                                    ClassLoader::perf_class_verify_selftime(),
                                    ClassLoader::perf_classes_verified(),
                                    jt->get_thread_stat()->perf_recursion_counts_addr(),
                                    jt->get_thread_stat()->perf_timers_addr(),
                                    PerfClassTraceTime::CLASS_VERIFY);
           bool verify_ok = verify_code(this_oop, throw_verifyerror, THREAD);
           if (!verify_ok) {
             return false;
           }
         }
         // Just in case a side-effect of verify linked this class already
         // (which can sometimes happen since the verifier loads classes
         // using custom class loaders, which are free to initialize things)
         if (this_oop->is_linked()) {
           return true;
         }
         // also sets rewritten
         this_oop->rewrite_class(CHECK_false);
       }
       // Initialize the vtable and interface table after
       // methods have been rewritten since rewrite may
       // fabricate new methodOops.
       // also does loader constraint checking
       if (!this_oop()->is_shared()) {
         ResourceMark rm(THREAD);
         this_oop->vtable()->initialize_vtable(true, CHECK_false);
         this_oop->itable()->initialize_itable(true, CHECK_false);
       }
 #ifdef ASSERT
       else {
         ResourceMark rm(THREAD);
         this_oop->vtable()->verify(tty, true);
         // In case itable verification is ever added.
         // this_oop->itable()->verify(tty, true);
       }
 #endif
       this_oop->set_init_state(linked);
       if (JvmtiExport::should_post_class_prepare()) {
         Thread *thread = THREAD;
         assert(thread->is_Java_thread(), "thread->is_Java_thread()");
         JvmtiExport::post_class_prepare((JavaThread *) thread, this_oop());
       }
     }
   }
   return true;
 }
 // Rewrite the byte codes of all of the methods of a class.
 // Three cases:
 //    During the link of a newly loaded class.
 //    During the preloading of classes to be written to the shared spaces.
 //      - Rewrite the methods and update the method entry points.
 //
 //    During the link of a class in the shared spaces.
 //      - The methods were already rewritten, update the metho entry points.
 //
 // The rewriter must be called exactly once. Rewriting must happen after
 // verification but before the first method of the class is executed.
 void instanceKlass::rewrite_class(TRAPS) {
   assert(is_loaded(), "must be loaded");
   instanceKlassHandle this_oop(THREAD, this->as_klassOop());
   if (this_oop->is_rewritten()) {
     assert(this_oop()->is_shared(), "rewriting an unshared class?");
     return;
   }
   Rewriter::rewrite(this_oop, CHECK); // No exception can happen here
   this_oop->set_rewritten();
 }
 void instanceKlass::initialize_impl(instanceKlassHandle this_oop, TRAPS) {
   // Make sure klass is linked (verified) before initialization
   // A class could already be verified, since it has been reflected upon.
   this_oop->link_class(CHECK);
   DTRACE_CLASSINIT_PROBE(required, instanceKlass::cast(this_oop()), -1);
   bool wait = false;
   // refer to the JVM book page 47 for description of steps
   // Step 1
   { ObjectLocker ol(this_oop, THREAD);
     Thread *self = THREAD; // it's passed the current thread
     // Step 2
     // If we were to use wait() instead of waitInterruptibly() then
     // we might end up throwing IE from link/symbol resolution sites
     // that aren't expected to throw.  This would wreak havoc.  See 6320309.
     while(this_oop->is_being_initialized() && !this_oop->is_reentrant_initialization(self)) {
         wait = true;
       ol.waitUninterruptibly(CHECK);
     }
     // Step 3
     if (this_oop->is_being_initialized() && this_oop->is_reentrant_initialization(self)) {
       DTRACE_CLASSINIT_PROBE_WAIT(recursive, instanceKlass::cast(this_oop()), -1,wait);
       return;
     }
     // Step 4
     if (this_oop->is_initialized()) {
       DTRACE_CLASSINIT_PROBE_WAIT(concurrent, instanceKlass::cast(this_oop()), -1,wait);
       return;
     }
     // Step 5
     if (this_oop->is_in_error_state()) {
       DTRACE_CLASSINIT_PROBE_WAIT(erroneous, instanceKlass::cast(this_oop()), -1,wait);
       ResourceMark rm(THREAD);
       const char* desc = "Could not initialize class ";
       const char* className = this_oop->external_name();
       size_t msglen = strlen(desc) + strlen(className) + 1;
       char* message = NEW_RESOURCE_ARRAY(char, msglen);
       if (NULL == message) {
         // Out of memory: can't create detailed error message
         THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), className);
       } else {
         jio_snprintf(message, msglen, "%s%s", desc, className);
         THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), message);
       }
     }
     // Step 6
     this_oop->set_init_state(being_initialized);
     this_oop->set_init_thread(self);
   }
   // Step 7
   klassOop super_klass = this_oop->super();
   if (super_klass != NULL && !this_oop->is_interface() && Klass::cast(super_klass)->should_be_initialized()) {
     Klass::cast(super_klass)->initialize(THREAD);
     if (HAS_PENDING_EXCEPTION) {
       Handle e(THREAD, PENDING_EXCEPTION);
       CLEAR_PENDING_EXCEPTION;
       {
         EXCEPTION_MARK;
         this_oop->set_initialization_state_and_notify(initialization_error, THREAD); // Locks object, set state, and notify all waiting threads
         CLEAR_PENDING_EXCEPTION;   // ignore any exception thrown, superclass initialization error is thrown below
       }
       DTRACE_CLASSINIT_PROBE_WAIT(super__failed, instanceKlass::cast(this_oop()), -1,wait);
       THROW_OOP(e());
     }
   }
   // Step 8
   {
     assert(THREAD->is_Java_thread(), "non-JavaThread in initialize_impl");
     JavaThread* jt = (JavaThread*)THREAD;
     DTRACE_CLASSINIT_PROBE_WAIT(clinit, instanceKlass::cast(this_oop()), -1,wait);
     // Timer includes any side effects of class initialization (resolution,
     // etc), but not recursive entry into call_class_initializer().
     PerfClassTraceTime timer(ClassLoader::perf_class_init_time(),
                              ClassLoader::perf_class_init_selftime(),
                              ClassLoader::perf_classes_inited(),
                              jt->get_thread_stat()->perf_recursion_counts_addr(),
                              jt->get_thread_stat()->perf_timers_addr(),
                              PerfClassTraceTime::CLASS_CLINIT);
     this_oop->call_class_initializer(THREAD);
   }
   // Step 9
   if (!HAS_PENDING_EXCEPTION) {
     this_oop->set_initialization_state_and_notify(fully_initialized, CHECK);
     { ResourceMark rm(THREAD);
       debug_only(this_oop->vtable()->verify(tty, true);)
     }
   }
   else {
     // Step 10 and 11
     Handle e(THREAD, PENDING_EXCEPTION);
     CLEAR_PENDING_EXCEPTION;
     {
       EXCEPTION_MARK;
       this_oop->set_initialization_state_and_notify(initialization_error, THREAD);
       CLEAR_PENDING_EXCEPTION;   // ignore any exception thrown, class initialization error is thrown below
     }
     DTRACE_CLASSINIT_PROBE_WAIT(error, instanceKlass::cast(this_oop()), -1,wait);
     if (e->is_a(SystemDictionary::Error_klass())) {
       THROW_OOP(e());
     } else {
       JavaCallArguments args(e);
       THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(),
                 vmSymbols::throwable_void_signature(),
                 &args);
     }
   }
   DTRACE_CLASSINIT_PROBE_WAIT(end, instanceKlass::cast(this_oop()), -1,wait);
 }
 // Note: implementation moved to static method to expose the this pointer.
 void instanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) {
   instanceKlassHandle kh(THREAD, this->as_klassOop());
   set_initialization_state_and_notify_impl(kh, state, CHECK);
 }
 void instanceKlass::set_initialization_state_and_notify_impl(instanceKlassHandle this_oop, ClassState state, TRAPS) {
   ObjectLocker ol(this_oop, THREAD);
   this_oop->set_init_state(state);
   ol.notify_all(CHECK);
 }
 void instanceKlass::add_implementor(klassOop k) {
   assert(Compile_lock->owned_by_self(), "");
   // Filter out my subinterfaces.
   // (Note: Interfaces are never on the subklass list.)
   if (instanceKlass::cast(k)->is_interface()) return;
   // Filter out subclasses whose supers already implement me.
   // (Note: CHA must walk subclasses of direct implementors
   // in order to locate indirect implementors.)
   klassOop sk = instanceKlass::cast(k)->super();
   if (sk != NULL && instanceKlass::cast(sk)->implements_interface(as_klassOop()))
     // We only need to check one immediate superclass, since the
     // implements_interface query looks at transitive_interfaces.
     // Any supers of the super have the same (or fewer) transitive_interfaces.
     return;
   // Update number of implementors
   int i = _nof_implementors++;
   // Record this implementor, if there are not too many already
   if (i < implementors_limit) {
     assert(_implementors[i] == NULL, "should be exactly one implementor");
     oop_store_without_check((oop*)&_implementors[i], k);
   } else if (i == implementors_limit) {
     // clear out the list on first overflow
     for (int i2 = 0; i2 < implementors_limit; i2++)
       oop_store_without_check((oop*)&_implementors[i2], NULL);
   }
   // The implementor also implements the transitive_interfaces
   for (int index = 0; index < local_interfaces()->length(); index++) {
     instanceKlass::cast(klassOop(local_interfaces()->obj_at(index)))->add_implementor(k);
   }
 }
 void instanceKlass::init_implementor() {
   for (int i = 0; i < implementors_limit; i++)
     oop_store_without_check((oop*)&_implementors[i], NULL);
   _nof_implementors = 0;
 }
 void instanceKlass::process_interfaces(Thread *thread) {
   // link this class into the implementors list of every interface it implements
   KlassHandle this_as_oop (thread, this->as_klassOop());
   for (int i = local_interfaces()->length() - 1; i >= 0; i--) {
     assert(local_interfaces()->obj_at(i)->is_klass(), "must be a klass");
     instanceKlass* interf = instanceKlass::cast(klassOop(local_interfaces()->obj_at(i)));
     assert(interf->is_interface(), "expected interface");
     interf->add_implementor(this_as_oop());
   }
 }
 bool instanceKlass::can_be_primary_super_slow() const {
   if (is_interface())
     return false;
   else
     return Klass::can_be_primary_super_slow();
 }
 objArrayOop instanceKlass::compute_secondary_supers(int num_extra_slots, TRAPS) {
   // The secondaries are the implemented interfaces.
   instanceKlass* ik = instanceKlass::cast(as_klassOop());
   objArrayHandle interfaces (THREAD, ik->transitive_interfaces());
   int num_secondaries = num_extra_slots + interfaces->length();
   if (num_secondaries == 0) {
     return Universe::the_empty_system_obj_array();
   } else if (num_extra_slots == 0) {
     return interfaces();
   } else {
     // a mix of both
     objArrayOop secondaries = oopFactory::new_system_objArray(num_secondaries, CHECK_NULL);
     for (int i = 0; i < interfaces->length(); i++) {
       secondaries->obj_at_put(num_extra_slots+i, interfaces->obj_at(i));
     }
     return secondaries;
   }
 }
 bool instanceKlass::compute_is_subtype_of(klassOop k) {
   if (Klass::cast(k)->is_interface()) {
     return implements_interface(k);
   } else {
     return Klass::compute_is_subtype_of(k);
   }
 }
 bool instanceKlass::implements_interface(klassOop k) const {
   if (as_klassOop() == k) return true;
   assert(Klass::cast(k)->is_interface(), "should be an interface class");
   for (int i = 0; i < transitive_interfaces()->length(); i++) {
     if (transitive_interfaces()->obj_at(i) == k) {
       return true;
     }
   }
   return false;
 }
 objArrayOop instanceKlass::allocate_objArray(int n, int length, TRAPS) {
   if (length < 0) THROW_0(vmSymbols::java_lang_NegativeArraySizeException());
   if (length > arrayOopDesc::max_array_length(T_OBJECT)) {
     report_java_out_of_memory("Requested array size exceeds VM limit");
     THROW_OOP_0(Universe::out_of_memory_error_array_size());
   }
   int size = objArrayOopDesc::object_size(length);
   klassOop ak = array_klass(n, CHECK_NULL);
   KlassHandle h_ak (THREAD, ak);
   objArrayOop o =
     (objArrayOop)CollectedHeap::array_allocate(h_ak, size, length, CHECK_NULL);
   return o;
 }
 instanceOop instanceKlass::register_finalizer(instanceOop i, TRAPS) {
   if (TraceFinalizerRegistration) {
     tty->print("Registered ");
     i->print_value_on(tty);
     tty->print_cr(" (" INTPTR_FORMAT ") as finalizable", (address)i);
   }
   instanceHandle h_i(THREAD, i);
   // Pass the handle as argument, JavaCalls::call expects oop as jobjects
   JavaValue result(T_VOID);
   JavaCallArguments args(h_i);
   methodHandle mh (THREAD, Universe::finalizer_register_method());
   JavaCalls::call(&result, mh, &args, CHECK_NULL);
   return h_i();
 }
 instanceOop instanceKlass::allocate_instance(TRAPS) {
   bool has_finalizer_flag = has_finalizer(); // Query before possible GC
   int size = size_helper();  // Query before forming handle.
   KlassHandle h_k(THREAD, as_klassOop());
   instanceOop i;
   i = (instanceOop)CollectedHeap::obj_allocate(h_k, size, CHECK_NULL);
   if (has_finalizer_flag && !RegisterFinalizersAtInit) {
     i = register_finalizer(i, CHECK_NULL);
   }
   return i;
 }
 instanceOop instanceKlass::allocate_permanent_instance(TRAPS) {
   // Finalizer registration occurs in the Object.<init> constructor
   // and constructors normally aren't run when allocating perm
   // instances so simply disallow finalizable perm objects.  This can
   // be relaxed if a need for it is found.
   assert(!has_finalizer(), "perm objects not allowed to have finalizers");
   int size = size_helper();  // Query before forming handle.
   KlassHandle h_k(THREAD, as_klassOop());
   instanceOop i = (instanceOop)
     CollectedHeap::permanent_obj_allocate(h_k, size, CHECK_NULL);
   return i;
 }
 void instanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) {
   if (is_interface() || is_abstract()) {
     ResourceMark rm(THREAD);
     THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
               : vmSymbols::java_lang_InstantiationException(), external_name());
   }
   if (as_klassOop() == SystemDictionary::Class_klass()) {
     ResourceMark rm(THREAD);
     THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError()
               : vmSymbols::java_lang_IllegalAccessException(), external_name());
   }
 }
 klassOop instanceKlass::array_klass_impl(bool or_null, int n, TRAPS) {
   instanceKlassHandle this_oop(THREAD, as_klassOop());
   return array_klass_impl(this_oop, or_null, n, THREAD);
 }
 klassOop instanceKlass::array_klass_impl(instanceKlassHandle this_oop, bool or_null, int n, TRAPS) {
   if (this_oop->array_klasses() == NULL) {
     if (or_null) return NULL;
     ResourceMark rm;
     JavaThread *jt = (JavaThread *)THREAD;
     {
       // Atomic creation of array_klasses
       MutexLocker mc(Compile_lock, THREAD);   // for vtables
       MutexLocker ma(MultiArray_lock, THREAD);
       // Check if update has already taken place
       if (this_oop->array_klasses() == NULL) {
         objArrayKlassKlass* oakk =
           (objArrayKlassKlass*)Universe::objArrayKlassKlassObj()->klass_part();
         klassOop  k = oakk->allocate_objArray_klass(1, this_oop, CHECK_NULL);
         this_oop->set_array_klasses(k);
       }
     }
   }
   // _this will always be set at this point
   objArrayKlass* oak = (objArrayKlass*)this_oop->array_klasses()->klass_part();
   if (or_null) {
     return oak->array_klass_or_null(n);
   }
   return oak->array_klass(n, CHECK_NULL);
 }
 klassOop instanceKlass::array_klass_impl(bool or_null, TRAPS) {
   return array_klass_impl(or_null, 1, THREAD);
 }
 void instanceKlass::call_class_initializer(TRAPS) {
   instanceKlassHandle ik (THREAD, as_klassOop());
   call_class_initializer_impl(ik, THREAD);
 }
 static int call_class_initializer_impl_counter = 0;   // for debugging
 methodOop instanceKlass::class_initializer() {
   methodOop clinit = find_method(
       vmSymbols::class_initializer_name(), vmSymbols::void_method_signature());
   if (clinit != NULL && clinit->has_valid_initializer_flags()) {
     return clinit;
   }
   return NULL;
 }
 void instanceKlass::call_class_initializer_impl(instanceKlassHandle this_oop, TRAPS) {
   methodHandle h_method(THREAD, this_oop->class_initializer());
   assert(!this_oop->is_initialized(), "we cannot initialize twice");
   if (TraceClassInitialization) {
     tty->print("%d Initializing ", call_class_initializer_impl_counter++);
     this_oop->name()->print_value();
     tty->print_cr("%s (" INTPTR_FORMAT ")", h_method() == NULL ? "(no method)" : "", (address)this_oop());
   }
   if (h_method() != NULL) {
     JavaCallArguments args; // No arguments
     JavaValue result(T_VOID);
     JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args)
   }
 }
 void instanceKlass::mask_for(methodHandle method, int bci,
   InterpreterOopMap* entry_for) {
   // Dirty read, then double-check under a lock.
   if (_oop_map_cache == NULL) {
     // Otherwise, allocate a new one.
     MutexLocker x(OopMapCacheAlloc_lock);
     // First time use. Allocate a cache in C heap
     if (_oop_map_cache == NULL) {
       _oop_map_cache = new OopMapCache();
     }
   }
   // _oop_map_cache is constant after init; lookup below does is own locking.
   _oop_map_cache->lookup(method, bci, entry_for);
 }
 bool instanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
   const int n = fields()->length();
   for (int i = 0; i < n; i += next_offset ) {
     int name_index = fields()->ushort_at(i + name_index_offset);
     int sig_index  = fields()->ushort_at(i + signature_index_offset);
     Symbol* f_name = constants()->symbol_at(name_index);
     Symbol* f_sig  = constants()->symbol_at(sig_index);
     if (f_name == name && f_sig == sig) {
       fd->initialize(as_klassOop(), i);
       return true;
     }
   }
   return false;
 }
 void instanceKlass::shared_symbols_iterate(SymbolClosure* closure) {
   Klass::shared_symbols_iterate(closure);
   closure->do_symbol(&_generic_signature);
   closure->do_symbol(&_source_file_name);
   closure->do_symbol(&_source_debug_extension);
   const int n = fields()->length();
   for (int i = 0; i < n; i += next_offset ) {
     int name_index = fields()->ushort_at(i + name_index_offset);
     closure->do_symbol(constants()->symbol_at_addr(name_index));
     int sig_index  = fields()->ushort_at(i + signature_index_offset);
     closure->do_symbol(constants()->symbol_at_addr(sig_index));
   }
 }
 klassOop instanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
   const int n = local_interfaces()->length();
   for (int i = 0; i < n; i++) {
     klassOop intf1 = klassOop(local_interfaces()->obj_at(i));
     assert(Klass::cast(intf1)->is_interface(), "just checking type");
     // search for field in current interface
     if (instanceKlass::cast(intf1)->find_local_field(name, sig, fd)) {
       assert(fd->is_static(), "interface field must be static");
       return intf1;
     }
     // search for field in direct superinterfaces
     klassOop intf2 = instanceKlass::cast(intf1)->find_interface_field(name, sig, fd);
     if (intf2 != NULL) return intf2;
   }
   // otherwise field lookup fails
   return NULL;
 }
 klassOop instanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
   // search order according to newest JVM spec (5.4.3.2, p.167).
   // 1) search for field in current klass
   if (find_local_field(name, sig, fd)) {
     return as_klassOop();
   }
   // 2) search for field recursively in direct superinterfaces
   { klassOop intf = find_interface_field(name, sig, fd);
     if (intf != NULL) return intf;
   }
   // 3) apply field lookup recursively if superclass exists
   { klassOop supr = super();
     if (supr != NULL) return instanceKlass::cast(supr)->find_field(name, sig, fd);
   }
   // 4) otherwise field lookup fails
   return NULL;
 }
 klassOop instanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const {
   // search order according to newest JVM spec (5.4.3.2, p.167).
   // 1) search for field in current klass
   if (find_local_field(name, sig, fd)) {
     if (fd->is_static() == is_static) return as_klassOop();
   }
   // 2) search for field recursively in direct superinterfaces
   if (is_static) {
     klassOop intf = find_interface_field(name, sig, fd);
     if (intf != NULL) return intf;
   }
   // 3) apply field lookup recursively if superclass exists
   { klassOop supr = super();
     if (supr != NULL) return instanceKlass::cast(supr)->find_field(name, sig, is_static, fd);
   }
   // 4) otherwise field lookup fails
   return NULL;
 }
 bool instanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
   int length = fields()->length();
   for (int i = 0; i < length; i += next_offset) {
     if (offset_from_fields( i ) == offset) {
       fd->initialize(as_klassOop(), i);
       if (fd->is_static() == is_static) return true;
     }
   }
   return false;
 }
 bool instanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
   klassOop klass = as_klassOop();
   while (klass != NULL) {
     if (instanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) {
       return true;
     }
     klass = Klass::cast(klass)->super();
   }
   return false;
 }
 void instanceKlass::methods_do(void f(methodOop method)) {
   int len = methods()->length();
   for (int index = 0; index < len; index++) {
     methodOop m = methodOop(methods()->obj_at(index));
     assert(m->is_method(), "must be method");
     f(m);
   }
 }
 void instanceKlass::do_local_static_fields(FieldClosure* cl) {
   fieldDescriptor fd;
   int length = fields()->length();
   for (int i = 0; i < length; i += next_offset) {
     fd.initialize(as_klassOop(), i);
     if (fd.is_static()) cl->do_field(&fd);
   }
 }
 void instanceKlass::do_local_static_fields(void f(fieldDescriptor*, TRAPS), TRAPS) {
   instanceKlassHandle h_this(THREAD, as_klassOop());
   do_local_static_fields_impl(h_this, f, CHECK);
 }
 void instanceKlass::do_local_static_fields_impl(instanceKlassHandle this_oop, void f(fieldDescriptor* fd, TRAPS), TRAPS) {
   fieldDescriptor fd;
   int length = this_oop->fields()->length();
   for (int i = 0; i < length; i += next_offset) {
     fd.initialize(this_oop(), i);
     if (fd.is_static()) { f(&fd, CHECK); } // Do NOT remove {}! (CHECK macro expands into several statements)
   }
 }
 static int compare_fields_by_offset(int* a, int* b) {
   return a[0] - b[0];
 }
 void instanceKlass::do_nonstatic_fields(FieldClosure* cl) {
   instanceKlass* super = superklass();
   if (super != NULL) {
     super->do_nonstatic_fields(cl);
   }
   fieldDescriptor fd;
   int length = fields()->length();
   // In DebugInfo nonstatic fields are sorted by offset.
   int* fields_sorted = NEW_C_HEAP_ARRAY(int, 2*(length+1));
   int j = 0;
   for (int i = 0; i < length; i += next_offset) {
     fd.initialize(as_klassOop(), i);
     if (!fd.is_static()) {
       fields_sorted[j + 0] = fd.offset();
       fields_sorted[j + 1] = i;
       j += 2;
     }
   }
   if (j > 0) {
     length = j;
     // _sort_Fn is defined in growableArray.hpp.
     qsort(fields_sorted, length/2, 2*sizeof(int), (_sort_Fn)compare_fields_by_offset);
     for (int i = 0; i < length; i += 2) {
       fd.initialize(as_klassOop(), fields_sorted[i + 1]);
       assert(!fd.is_static() && fd.offset() == fields_sorted[i], "only nonstatic fields");
       cl->do_field(&fd);
     }
   }
   FREE_C_HEAP_ARRAY(int, fields_sorted);
 }
 void instanceKlass::array_klasses_do(void f(klassOop k)) {
   if (array_klasses() != NULL)
     arrayKlass::cast(array_klasses())->array_klasses_do(f);
 }
 void instanceKlass::with_array_klasses_do(void f(klassOop k)) {
   f(as_klassOop());
   array_klasses_do(f);
 }
 #ifdef ASSERT
 static int linear_search(objArrayOop methods, Symbol* name, Symbol* signature) {
   int len = methods->length();
   for (int index = 0; index < len; index++) {
     methodOop m = (methodOop)(methods->obj_at(index));
     assert(m->is_method(), "must be method");
     if (m->signature() == signature && m->name() == name) {
        return index;
     }
   }
   return -1;
 }
 #endif
 methodOop instanceKlass::find_method(Symbol* name, Symbol* signature) const {
   return instanceKlass::find_method(methods(), name, signature);
 }
 methodOop instanceKlass::find_method(objArrayOop methods, Symbol* name, Symbol* signature) {
   int len = methods->length();
   // methods are sorted, so do binary search
   int l = 0;
   int h = len - 1;
   while (l <= h) {
     int mid = (l + h) >> 1;
     methodOop m = (methodOop)methods->obj_at(mid);
     assert(m->is_method(), "must be method");
     int res = m->name()->fast_compare(name);
     if (res == 0) {
       // found matching name; do linear search to find matching signature
       // first, quick check for common case
       if (m->signature() == signature) return m;
       // search downwards through overloaded methods
       int i;
       for (i = mid - 1; i >= l; i--) {
         methodOop m = (methodOop)methods->obj_at(i);
         assert(m->is_method(), "must be method");
         if (m->name() != name) break;
         if (m->signature() == signature) return m;
       }
       // search upwards
       for (i = mid + 1; i <= h; i++) {
         methodOop m = (methodOop)methods->obj_at(i);
         assert(m->is_method(), "must be method");
         if (m->name() != name) break;
         if (m->signature() == signature) return m;
       }
       // not found
 #ifdef ASSERT
       int index = linear_search(methods, name, signature);
       assert(index == -1, err_msg("binary search should have found entry %d", index));
 #endif
       return NULL;
     } else if (res < 0) {
       l = mid + 1;
     } else {
       h = mid - 1;
     }
   }
 #ifdef ASSERT
   int index = linear_search(methods, name, signature);
   assert(index == -1, err_msg("binary search should have found entry %d", index));
 #endif
   return NULL;
 }
 methodOop instanceKlass::uncached_lookup_method(Symbol* name, Symbol* signature) const {
   klassOop klass = as_klassOop();
   while (klass != NULL) {
     methodOop method = instanceKlass::cast(klass)->find_method(name, signature);
     if (method != NULL) return method;
     klass = instanceKlass::cast(klass)->super();
   }
   return NULL;
 }
 // lookup a method in all the interfaces that this class implements
 methodOop instanceKlass::lookup_method_in_all_interfaces(Symbol* name,
                                                          Symbol* signature) const {
   objArrayOop all_ifs = instanceKlass::cast(as_klassOop())->transitive_interfaces();
   int num_ifs = all_ifs->length();
   instanceKlass *ik = NULL;
   for (int i = 0; i < num_ifs; i++) {
     ik = instanceKlass::cast(klassOop(all_ifs->obj_at(i)));
     methodOop m = ik->lookup_method(name, signature);
     if (m != NULL) {
       return m;
     }
   }
   return NULL;
 }
 /* jni_id_for_impl for jfieldIds only */
 JNIid* instanceKlass::jni_id_for_impl(instanceKlassHandle this_oop, int offset) {
   MutexLocker ml(JfieldIdCreation_lock);
   // Retry lookup after we got the lock
   JNIid* probe = this_oop->jni_ids() == NULL ? NULL : this_oop->jni_ids()->find(offset);
   if (probe == NULL) {
     // Slow case, allocate new static field identifier
     probe = new JNIid(this_oop->as_klassOop(), offset, this_oop->jni_ids());
     this_oop->set_jni_ids(probe);
   }
   return probe;
 }
 /* jni_id_for for jfieldIds only */
 JNIid* instanceKlass::jni_id_for(int offset) {
   JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset);
   if (probe == NULL) {
     probe = jni_id_for_impl(this->as_klassOop(), offset);
   }
   return probe;
 }
 // Lookup or create a jmethodID.
 // This code is called by the VMThread and JavaThreads so the
 // locking has to be done very carefully to avoid deadlocks
 // and/or other cache consistency problems.
 //
 jmethodID instanceKlass::get_jmethod_id(instanceKlassHandle ik_h, methodHandle method_h) {
   size_t idnum = (size_t)method_h->method_idnum();
   jmethodID* jmeths = ik_h->methods_jmethod_ids_acquire();
   size_t length = 0;
   jmethodID id = NULL;
   // We use a double-check locking idiom here because this cache is
   // performance sensitive. In the normal system, this cache only
   // transitions from NULL to non-NULL which is safe because we use
   // release_set_methods_jmethod_ids() to advertise the new cache.
   // A partially constructed cache should never be seen by a racing
   // thread. We also use release_store_ptr() to save a new jmethodID
   // in the cache so a partially constructed jmethodID should never be
   // seen either. Cache reads of existing jmethodIDs proceed without a
   // lock, but cache writes of a new jmethodID requires uniqueness and
   // creation of the cache itself requires no leaks so a lock is
   // generally acquired in those two cases.
   //
   // If the RedefineClasses() API has been used, then this cache can
   // grow and we'll have transitions from non-NULL to bigger non-NULL.
   // Cache creation requires no leaks and we require safety between all
   // cache accesses and freeing of the old cache so a lock is generally
   // acquired when the RedefineClasses() API has been used.
   if (jmeths != NULL) {
     // the cache already exists
     if (!ik_h->idnum_can_increment()) {
       // the cache can't grow so we can just get the current values
       get_jmethod_id_length_value(jmeths, idnum, &length, &id);
     } else {
       // cache can grow so we have to be more careful
       if (Threads::number_of_threads() == 0 ||
           SafepointSynchronize::is_at_safepoint()) {
         // we're single threaded or at a safepoint - no locking needed
         get_jmethod_id_length_value(jmeths, idnum, &length, &id);
       } else {
         MutexLocker ml(JmethodIdCreation_lock);
         get_jmethod_id_length_value(jmeths, idnum, &length, &id);
       }
     }
   }
   // implied else:
   // we need to allocate a cache so default length and id values are good
   if (jmeths == NULL ||   // no cache yet
       length <= idnum ||  // cache is too short
       id == NULL) {       // cache doesn't contain entry
     // This function can be called by the VMThread so we have to do all
     // things that might block on a safepoint before grabbing the lock.
     // Otherwise, we can deadlock with the VMThread or have a cache
     // consistency issue. These vars keep track of what we might have
     // to free after the lock is dropped.
     jmethodID  to_dealloc_id     = NULL;
     jmethodID* to_dealloc_jmeths = NULL;
     // may not allocate new_jmeths or use it if we allocate it
     jmethodID* new_jmeths = NULL;
     if (length <= idnum) {
       // allocate a new cache that might be used
       size_t size = MAX2(idnum+1, (size_t)ik_h->idnum_allocated_count());
       new_jmeths = NEW_C_HEAP_ARRAY(jmethodID, size+1);
       memset(new_jmeths, 0, (size+1)*sizeof(jmethodID));
       // cache size is stored in element[0], other elements offset by one
       new_jmeths[0] = (jmethodID)size;
     }
     // allocate a new jmethodID that might be used
     jmethodID new_id = NULL;
     if (method_h->is_old() && !method_h->is_obsolete()) {
       // The method passed in is old (but not obsolete), we need to use the current version
       methodOop current_method = ik_h->method_with_idnum((int)idnum);
       assert(current_method != NULL, "old and but not obsolete, so should exist");
       methodHandle current_method_h(current_method == NULL? method_h() : current_method);
       new_id = JNIHandles::make_jmethod_id(current_method_h);
     } else {
       // It is the current version of the method or an obsolete method,
       // use the version passed in
       new_id = JNIHandles::make_jmethod_id(method_h);
     }
     if (Threads::number_of_threads() == 0 ||
         SafepointSynchronize::is_at_safepoint()) {
       // we're single threaded or at a safepoint - no locking needed
       id = get_jmethod_id_fetch_or_update(ik_h, idnum, new_id, new_jmeths,
                                           &to_dealloc_id, &to_dealloc_jmeths);
     } else {
       MutexLocker ml(JmethodIdCreation_lock);
       id = get_jmethod_id_fetch_or_update(ik_h, idnum, new_id, new_jmeths,
                                           &to_dealloc_id, &to_dealloc_jmeths);
     }
     // The lock has been dropped so we can free resources.
     // Free up either the old cache or the new cache if we allocated one.
     if (to_dealloc_jmeths != NULL) {
       FreeHeap(to_dealloc_jmeths);
     }
     // free up the new ID since it wasn't needed
     if (to_dealloc_id != NULL) {
       JNIHandles::destroy_jmethod_id(to_dealloc_id);
     }
   }
   return id;
 }
 // Common code to fetch the jmethodID from the cache or update the
 // cache with the new jmethodID. This function should never do anything
 // that causes the caller to go to a safepoint or we can deadlock with
 // the VMThread or have cache consistency issues.
 //
 jmethodID instanceKlass::get_jmethod_id_fetch_or_update(
             instanceKlassHandle ik_h, size_t idnum, jmethodID new_id,
             jmethodID* new_jmeths, jmethodID* to_dealloc_id_p,
             jmethodID** to_dealloc_jmeths_p) {
   assert(new_id != NULL, "sanity check");
   assert(to_dealloc_id_p != NULL, "sanity check");
   assert(to_dealloc_jmeths_p != NULL, "sanity check");
   assert(Threads::number_of_threads() == 0 ||
          SafepointSynchronize::is_at_safepoint() ||
          JmethodIdCreation_lock->owned_by_self(), "sanity check");
   // reacquire the cache - we are locked, single threaded or at a safepoint
   jmethodID* jmeths = ik_h->methods_jmethod_ids_acquire();
   jmethodID  id     = NULL;
   size_t     length = 0;
   if (jmeths == NULL ||                         // no cache yet
       (length = (size_t)jmeths[0]) <= idnum) {  // cache is too short
     if (jmeths != NULL) {
       // copy any existing entries from the old cache
       for (size_t index = 0; index < length; index++) {
         new_jmeths[index+1] = jmeths[index+1];
       }
       *to_dealloc_jmeths_p = jmeths;  // save old cache for later delete
     }
     ik_h->release_set_methods_jmethod_ids(jmeths = new_jmeths);
   } else {
     // fetch jmethodID (if any) from the existing cache
     id = jmeths[idnum+1];
     *to_dealloc_jmeths_p = new_jmeths;  // save new cache for later delete
   }
   if (id == NULL) {
     // No matching jmethodID in the existing cache or we have a new
     // cache or we just grew the cache. This cache write is done here
     // by the first thread to win the foot race because a jmethodID
     // needs to be unique once it is generally available.
     id = new_id;
     // The jmethodID cache can be read while unlocked so we have to
     // make sure the new jmethodID is complete before installing it
     // in the cache.
     OrderAccess::release_store_ptr(&jmeths[idnum+1], id);
   } else {
     *to_dealloc_id_p = new_id; // save new id for later delete
   }
   return id;
 }
 // Common code to get the jmethodID cache length and the jmethodID
 // value at index idnum if there is one.
 //
 void instanceKlass::get_jmethod_id_length_value(jmethodID* cache,
        size_t idnum, size_t *length_p, jmethodID* id_p) {
   assert(cache != NULL, "sanity check");
   assert(length_p != NULL, "sanity check");
   assert(id_p != NULL, "sanity check");
   // cache size is stored in element[0], other elements offset by one
   *length_p = (size_t)cache[0];
   if (*length_p <= idnum) {  // cache is too short
     *id_p = NULL;
   } else {
     *id_p = cache[idnum+1];  // fetch jmethodID (if any)
   }
 }
 // Lookup a jmethodID, NULL if not found.  Do no blocking, no allocations, no handles
 jmethodID instanceKlass::jmethod_id_or_null(methodOop method) {
   size_t idnum = (size_t)method->method_idnum();
   jmethodID* jmeths = methods_jmethod_ids_acquire();
   size_t length;                                // length assigned as debugging crumb
   jmethodID id = NULL;
   if (jmeths != NULL &&                         // If there is a cache
       (length = (size_t)jmeths[0]) > idnum) {   // and if it is long enough,
     id = jmeths[idnum+1];                       // Look up the id (may be NULL)
   }
   return id;
 }
 // Cache an itable index
 void instanceKlass::set_cached_itable_index(size_t idnum, int index) {
   int* indices = methods_cached_itable_indices_acquire();
   int* to_dealloc_indices = NULL;
   // We use a double-check locking idiom here because this cache is
   // performance sensitive. In the normal system, this cache only
   // transitions from NULL to non-NULL which is safe because we use
   // release_set_methods_cached_itable_indices() to advertise the
   // new cache. A partially constructed cache should never be seen
   // by a racing thread. Cache reads and writes proceed without a
   // lock, but creation of the cache itself requires no leaks so a
   // lock is generally acquired in that case.
   //
   // If the RedefineClasses() API has been used, then this cache can
   // grow and we'll have transitions from non-NULL to bigger non-NULL.
   // Cache creation requires no leaks and we require safety between all
   // cache accesses and freeing of the old cache so a lock is generally
   // acquired when the RedefineClasses() API has been used.
   if (indices == NULL || idnum_can_increment()) {
     // we need a cache or the cache can grow
     MutexLocker ml(JNICachedItableIndex_lock);
     // reacquire the cache to see if another thread already did the work
     indices = methods_cached_itable_indices_acquire();
     size_t length = 0;
     // cache size is stored in element[0], other elements offset by one
     if (indices == NULL || (length = (size_t)indices[0]) <= idnum) {
       size_t size = MAX2(idnum+1, (size_t)idnum_allocated_count());
       int* new_indices = NEW_C_HEAP_ARRAY(int, size+1);
       new_indices[0] = (int)size;
       // copy any existing entries
       size_t i;
       for (i = 0; i < length; i++) {
         new_indices[i+1] = indices[i+1];
       }
       // Set all the rest to -1
       for (i = length; i < size; i++) {
         new_indices[i+1] = -1;
       }
       if (indices != NULL) {
         // We have an old cache to delete so save it for after we
         // drop the lock.
         to_dealloc_indices = indices;
       }
       release_set_methods_cached_itable_indices(indices = new_indices);
     }
     if (idnum_can_increment()) {
       // this cache can grow so we have to write to it safely
       indices[idnum+1] = index;
     }
   } else {
     CHECK_UNHANDLED_OOPS_ONLY(Thread::current()->clear_unhandled_oops());
   }
   if (!idnum_can_increment()) {
     // The cache cannot grow and this JNI itable index value does not
     // have to be unique like a jmethodID. If there is a race to set it,
     // it doesn't matter.
     indices[idnum+1] = index;
   }
   if (to_dealloc_indices != NULL) {
     // we allocated a new cache so free the old one
     FreeHeap(to_dealloc_indices);
   }
 }
 // Retrieve a cached itable index
 int instanceKlass::cached_itable_index(size_t idnum) {
   int* indices = methods_cached_itable_indices_acquire();
   if (indices != NULL && ((size_t)indices[0]) > idnum) {
      // indices exist and are long enough, retrieve possible cached
     return indices[idnum+1];
   }
   return -1;
 }
 //
 // nmethodBucket is used to record dependent nmethods for
 // deoptimization.  nmethod dependencies are actually <klass, method>
 // pairs but we really only care about the klass part for purposes of
 // finding nmethods which might need to be deoptimized.  Instead of
 // recording the method, a count of how many times a particular nmethod
 // was recorded is kept.  This ensures that any recording errors are
 // noticed since an nmethod should be removed as many times are it's
 // added.
 //
 class nmethodBucket {
  private:
   nmethod*       _nmethod;
   int            _count;
   nmethodBucket* _next;
  public:
   nmethodBucket(nmethod* nmethod, nmethodBucket* next) {
     _nmethod = nmethod;
     _next = next;
     _count = 1;
   }
   int count()                             { return _count; }
   int increment()                         { _count += 1; return _count; }
   int decrement()                         { _count -= 1; assert(_count >= 0, "don't underflow"); return _count; }
   nmethodBucket* next()                   { return _next; }
   void set_next(nmethodBucket* b)         { _next = b; }
   nmethod* get_nmethod()                  { return _nmethod; }
 };
 //
 // Walk the list of dependent nmethods searching for nmethods which
 // are dependent on the klassOop that was passed in and mark them for
 // deoptimization.  Returns the number of nmethods found.
 //
 int instanceKlass::mark_dependent_nmethods(DepChange& changes) {
   assert_locked_or_safepoint(CodeCache_lock);
   int found = 0;
   nmethodBucket* b = _dependencies;
   while (b != NULL) {
     nmethod* nm = b->get_nmethod();
     // since dependencies aren't removed until an nmethod becomes a zombie,
     // the dependency list may contain nmethods which aren't alive.
     if (nm->is_alive() && !nm->is_marked_for_deoptimization() && nm->check_dependency_on(changes)) {
       if (TraceDependencies) {
         ResourceMark rm;
         tty->print_cr("Marked for deoptimization");
         tty->print_cr("  context = %s", this->external_name());
         changes.print();
         nm->print();
         nm->print_dependencies();
       }
       nm->mark_for_deoptimization();
       found++;
     }
     b = b->next();
   }
   return found;
 }
 //
 // Add an nmethodBucket to the list of dependencies for this nmethod.
 // It's possible that an nmethod has multiple dependencies on this klass
 // so a count is kept for each bucket to guarantee that creation and
 // deletion of dependencies is consistent.
 //
 void instanceKlass::add_dependent_nmethod(nmethod* nm) {
   assert_locked_or_safepoint(CodeCache_lock);
   nmethodBucket* b = _dependencies;
   nmethodBucket* last = NULL;
   while (b != NULL) {
     if (nm == b->get_nmethod()) {
       b->increment();
       return;
     }
     b = b->next();
   }
   _dependencies = new nmethodBucket(nm, _dependencies);
 }
 //
 // Decrement count of the nmethod in the dependency list and remove
 // the bucket competely when the count goes to 0.  This method must
 // find a corresponding bucket otherwise there's a bug in the
 // recording of dependecies.
 //
 void instanceKlass::remove_dependent_nmethod(nmethod* nm) {
   assert_locked_or_safepoint(CodeCache_lock);
   nmethodBucket* b = _dependencies;
   nmethodBucket* last = NULL;
   while (b != NULL) {
     if (nm == b->get_nmethod()) {
       if (b->decrement() == 0) {
         if (last == NULL) {
           _dependencies = b->next();
         } else {
           last->set_next(b->next());
         }
         delete b;
       }
       return;
     }
     last = b;
     b = b->next();
   }
 #ifdef ASSERT
   tty->print_cr("### %s can't find dependent nmethod:", this->external_name());
   nm->print();
 #endif // ASSERT
   ShouldNotReachHere();
 }
 #ifndef PRODUCT
 void instanceKlass::print_dependent_nmethods(bool verbose) {
   nmethodBucket* b = _dependencies;
   int idx = 0;
   while (b != NULL) {
     nmethod* nm = b->get_nmethod();
     tty->print("[%d] count=%d { ", idx++, b->count());
     if (!verbose) {
       nm->print_on(tty, "nmethod");
       tty->print_cr(" } ");
     } else {
       nm->print();
       nm->print_dependencies();
       tty->print_cr("--- } ");
     }
     b = b->next();
   }
 }
 bool instanceKlass::is_dependent_nmethod(nmethod* nm) {
   nmethodBucket* b = _dependencies;
   while (b != NULL) {
     if (nm == b->get_nmethod()) {
       return true;
     }
     b = b->next();
   }
   return false;
 }
 #endif //PRODUCT
 #ifdef ASSERT
 template <class T> void assert_is_in(T *p) {
   T heap_oop = oopDesc::load_heap_oop(p);
   if (!oopDesc::is_null(heap_oop)) {
     oop o = oopDesc::decode_heap_oop_not_null(heap_oop);
     assert(Universe::heap()->is_in(o), "should be in heap");
   }
 }
 template <class T> void assert_is_in_closed_subset(T *p) {
   T heap_oop = oopDesc::load_heap_oop(p);
   if (!oopDesc::is_null(heap_oop)) {
     oop o = oopDesc::decode_heap_oop_not_null(heap_oop);
     assert(Universe::heap()->is_in_closed_subset(o), "should be in closed");
   }
 }
 template <class T> void assert_is_in_reserved(T *p) {
   T heap_oop = oopDesc::load_heap_oop(p);
   if (!oopDesc::is_null(heap_oop)) {
     oop o = oopDesc::decode_heap_oop_not_null(heap_oop);
     assert(Universe::heap()->is_in_reserved(o), "should be in reserved");
   }
 }
 template <class T> void assert_nothing(T *p) {}
 #else
 template <class T> void assert_is_in(T *p) {}
 template <class T> void assert_is_in_closed_subset(T *p) {}
 template <class T> void assert_is_in_reserved(T *p) {}
 template <class T> void assert_nothing(T *p) {}
 #endif // ASSERT
 //
 // Macros that iterate over areas of oops which are specialized on type of
 // oop pointer either narrow or wide, depending on UseCompressedOops
 //
 // Parameters are:
 //   T         - type of oop to point to (either oop or narrowOop)
 //   start_p   - starting pointer for region to iterate over
 //   count     - number of oops or narrowOops to iterate over
 //   do_oop    - action to perform on each oop (it's arbitrary C code which
 //               makes it more efficient to put in a macro rather than making
 //               it a template function)
 //   assert_fn - assert function which is template function because performance
 //               doesn't matter when enabled.
 #define InstanceKlass_SPECIALIZED_OOP_ITERATE( \
   T, start_p, count, do_oop,                \
   assert_fn)                                \
 {                                           \
   T* p         = (T*)(start_p);             \
   T* const end = p + (count);               \
   while (p < end) {                         \
     (assert_fn)(p);                         \
     do_oop;                                 \
     ++p;                                    \
   }                                         \
 }
 #define InstanceKlass_SPECIALIZED_OOP_REVERSE_ITERATE( \
   T, start_p, count, do_oop,                \
   assert_fn)                                \
 {                                           \
   T* const start = (T*)(start_p);           \
   T*       p     = start + (count);         \
   while (start < p) {                       \
     --p;                                    \
     (assert_fn)(p);                         \
     do_oop;                                 \
   }                                         \
 }
 #define InstanceKlass_SPECIALIZED_BOUNDED_OOP_ITERATE( \
   T, start_p, count, low, high,             \
   do_oop, assert_fn)                        \
 {                                           \
   T* const l = (T*)(low);                   \
   T* const h = (T*)(high);                  \
   assert(mask_bits((intptr_t)l, sizeof(T)-1) == 0 && \
          mask_bits((intptr_t)h, sizeof(T)-1) == 0,   \
          "bounded region must be properly aligned"); \
   T* p       = (T*)(start_p);               \
   T* end     = p + (count);                 \
   if (p < l) p = l;                         \
   if (end > h) end = h;                     \
   while (p < end) {                         \
     (assert_fn)(p);                         \
     do_oop;                                 \
     ++p;                                    \
   }                                         \
 }
 // The following macros call specialized macros, passing either oop or
 // narrowOop as the specialization type.  These test the UseCompressedOops
 // flag.
 #define InstanceKlass_OOP_ITERATE(start_p, count,    \
                                   do_oop, assert_fn) \
 {                                                    \
   if (UseCompressedOops) {                           \
     InstanceKlass_SPECIALIZED_OOP_ITERATE(narrowOop, \
       start_p, count,                                \
       do_oop, assert_fn)                             \
   } else {                                           \
     InstanceKlass_SPECIALIZED_OOP_ITERATE(oop,       \
       start_p, count,                                \
       do_oop, assert_fn)                             \
   }                                                  \
 }
 #define InstanceKlass_BOUNDED_OOP_ITERATE(start_p, count, low, high,    \
                                           do_oop, assert_fn) \
 {                                                            \
   if (UseCompressedOops) {                                   \
     InstanceKlass_SPECIALIZED_BOUNDED_OOP_ITERATE(narrowOop, \
       start_p, count,                                        \
       low, high,                                             \
       do_oop, assert_fn)                                     \
   } else {                                                   \
     InstanceKlass_SPECIALIZED_BOUNDED_OOP_ITERATE(oop,       \
       start_p, count,                                        \
       low, high,                                             \
       do_oop, assert_fn)                                     \
   }                                                          \
 }
 #define InstanceKlass_OOP_MAP_ITERATE(obj, do_oop, assert_fn)            \
 {                                                                        \
   /* Compute oopmap block range. The common case                         \
      is nonstatic_oop_map_size == 1. */                                  \
   OopMapBlock* map           = start_of_nonstatic_oop_maps();            \
   OopMapBlock* const end_map = map + nonstatic_oop_map_count();          \
   if (UseCompressedOops) {                                               \
     while (map < end_map) {                                              \
       InstanceKlass_SPECIALIZED_OOP_ITERATE(narrowOop,                   \
         obj->obj_field_addr<narrowOop>(map->offset()), map->count(),     \
         do_oop, assert_fn)                                               \
       ++map;                                                             \
     }                                                                    \
   } else {                                                               \
     while (map < end_map) {                                              \
       InstanceKlass_SPECIALIZED_OOP_ITERATE(oop,                         \
         obj->obj_field_addr<oop>(map->offset()), map->count(),           \
         do_oop, assert_fn)                                               \
       ++map;                                                             \
     }                                                                    \
   }                                                                      \
 }
 #define InstanceKlass_OOP_MAP_REVERSE_ITERATE(obj, do_oop, assert_fn)    \
 {                                                                        \
   OopMapBlock* const start_map = start_of_nonstatic_oop_maps();          \
   OopMapBlock* map             = start_map + nonstatic_oop_map_count();  \
   if (UseCompressedOops) {                                               \
     while (start_map < map) {                                            \
       --map;                                                             \
       InstanceKlass_SPECIALIZED_OOP_REVERSE_ITERATE(narrowOop,           \
         obj->obj_field_addr<narrowOop>(map->offset()), map->count(),     \
         do_oop, assert_fn)                                               \
     }                                                                    \
   } else {                                                               \
     while (start_map < map) {                                            \
       --map;                                                             \
       InstanceKlass_SPECIALIZED_OOP_REVERSE_ITERATE(oop,                 \
         obj->obj_field_addr<oop>(map->offset()), map->count(),           \
         do_oop, assert_fn)                                               \
     }                                                                    \
   }                                                                      \
 }
 #define InstanceKlass_BOUNDED_OOP_MAP_ITERATE(obj, low, high, do_oop,    \
                                               assert_fn)                 \
 {                                                                        \
   /* Compute oopmap block range. The common case is                      \
      nonstatic_oop_map_size == 1, so we accept the                       \
      usually non-existent extra overhead of examining                    \
      all the maps. */                                                    \
   OopMapBlock* map           = start_of_nonstatic_oop_maps();            \
   OopMapBlock* const end_map = map + nonstatic_oop_map_count();          \
   if (UseCompressedOops) {                                               \
     while (map < end_map) {                                              \
       InstanceKlass_SPECIALIZED_BOUNDED_OOP_ITERATE(narrowOop,           \
         obj->obj_field_addr<narrowOop>(map->offset()), map->count(),     \
         low, high,                                                       \
         do_oop, assert_fn)                                               \
       ++map;                                                             \
     }                                                                    \
   } else {                                                               \
     while (map < end_map) {                                              \
       InstanceKlass_SPECIALIZED_BOUNDED_OOP_ITERATE(oop,                 \
         obj->obj_field_addr<oop>(map->offset()), map->count(),           \
         low, high,                                                       \
         do_oop, assert_fn)                                               \
       ++map;                                                             \
     }                                                                    \
   }                                                                      \
 }
 void instanceKlass::follow_static_fields() {
   InstanceKlass_OOP_ITERATE( \
     start_of_static_fields(), static_oop_field_size(), \
     MarkSweep::mark_and_push(p), \
     assert_is_in_closed_subset)
 }
 #ifndef SERIALGC
 void instanceKlass::follow_static_fields(ParCompactionManager* cm) {
   InstanceKlass_OOP_ITERATE( \
     start_of_static_fields(), static_oop_field_size(), \
     PSParallelCompact::mark_and_push(cm, p), \
     assert_is_in)
 }
 #endif // SERIALGC
 void instanceKlass::adjust_static_fields() {
   InstanceKlass_OOP_ITERATE( \
     start_of_static_fields(), static_oop_field_size(), \
     MarkSweep::adjust_pointer(p), \
     assert_nothing)
 }
 #ifndef SERIALGC
 void instanceKlass::update_static_fields() {
   InstanceKlass_OOP_ITERATE( \
     start_of_static_fields(), static_oop_field_size(), \
     PSParallelCompact::adjust_pointer(p), \
     assert_nothing)
 }
 #endif // SERIALGC
 void instanceKlass::oop_follow_contents(oop obj) {
   assert(obj != NULL, "can't follow the content of NULL object");
   obj->follow_header();
   InstanceKlass_OOP_MAP_ITERATE( \
     obj, \
     MarkSweep::mark_and_push(p), \
     assert_is_in_closed_subset)
 }
 #ifndef SERIALGC
 void instanceKlass::oop_follow_contents(ParCompactionManager* cm,
                                         oop obj) {
   assert(obj != NULL, "can't follow the content of NULL object");
   obj->follow_header(cm);
   InstanceKlass_OOP_MAP_ITERATE( \
     obj, \
     PSParallelCompact::mark_and_push(cm, p), \
     assert_is_in)
 }
 #endif // SERIALGC
 // closure's do_header() method dicates whether the given closure should be
 // applied to the klass ptr in the object header.
 #define InstanceKlass_OOP_OOP_ITERATE_DEFN(OopClosureType, nv_suffix)        \
                                                                              \
 int instanceKlass::oop_oop_iterate##nv_suffix(oop obj, OopClosureType* closure) { \
   SpecializationStats::record_iterate_call##nv_suffix(SpecializationStats::ik);\
   /* header */                                                          \
   if (closure->do_header()) {                                           \
     obj->oop_iterate_header(closure);                                   \
   }                                                                     \
   InstanceKlass_OOP_MAP_ITERATE(                                        \
     obj,                                                                \
     SpecializationStats::                                               \
       record_do_oop_call##nv_suffix(SpecializationStats::ik);           \
     (closure)->do_oop##nv_suffix(p),                                    \
     assert_is_in_closed_subset)                                         \
   return size_helper();                                                 \
 }
 #ifndef SERIALGC
 #define InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DEFN(OopClosureType, nv_suffix) \
                                                                                 \
 int instanceKlass::oop_oop_iterate_backwards##nv_suffix(oop obj,                \
                                               OopClosureType* closure) {        \
   SpecializationStats::record_iterate_call##nv_suffix(SpecializationStats::ik); \
   /* header */                                                                  \
   if (closure->do_header()) {                                                   \
     obj->oop_iterate_header(closure);                                           \
   }                                                                             \
   /* instance variables */                                                      \
   InstanceKlass_OOP_MAP_REVERSE_ITERATE(                                        \
     obj,                                                                        \
     SpecializationStats::record_do_oop_call##nv_suffix(SpecializationStats::ik);\
     (closure)->do_oop##nv_suffix(p),                                            \
     assert_is_in_closed_subset)                                                 \
    return size_helper();                                                        \
 }
 #endif // !SERIALGC
 #define InstanceKlass_OOP_OOP_ITERATE_DEFN_m(OopClosureType, nv_suffix) \
                                                                         \
 int instanceKlass::oop_oop_iterate##nv_suffix##_m(oop obj,              \
                                                   OopClosureType* closure, \
                                                   MemRegion mr) {          \
   SpecializationStats::record_iterate_call##nv_suffix(SpecializationStats::ik);\
   if (closure->do_header()) {                                            \
     obj->oop_iterate_header(closure, mr);                                \
   }                                                                      \
   InstanceKlass_BOUNDED_OOP_MAP_ITERATE(                                 \
     obj, mr.start(), mr.end(),                                           \
     (closure)->do_oop##nv_suffix(p),                                     \
     assert_is_in_closed_subset)                                          \
   return size_helper();                                                  \
 }
 ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_DEFN)
 ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceKlass_OOP_OOP_ITERATE_DEFN)
 ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_DEFN_m)
 ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceKlass_OOP_OOP_ITERATE_DEFN_m)
 #ifndef SERIALGC
 ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DEFN)
 ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DEFN)
 #endif // !SERIALGC
 void instanceKlass::iterate_static_fields(OopClosure* closure) {
     InstanceKlass_OOP_ITERATE( \
       start_of_static_fields(), static_oop_field_size(), \
       closure->do_oop(p), \
       assert_is_in_reserved)
 }
 void instanceKlass::iterate_static_fields(OopClosure* closure,
                                           MemRegion mr) {
   InstanceKlass_BOUNDED_OOP_ITERATE( \
     start_of_static_fields(), static_oop_field_size(), \
     mr.start(), mr.end(), \
     (closure)->do_oop_v(p), \
     assert_is_in_closed_subset)
 }
 int instanceKlass::oop_adjust_pointers(oop obj) {
   int size = size_helper();
   InstanceKlass_OOP_MAP_ITERATE( \
     obj, \
     MarkSweep::adjust_pointer(p), \
     assert_is_in)
   obj->adjust_header();
   return size;
 }
 #ifndef SERIALGC
 void instanceKlass::oop_push_contents(PSPromotionManager* pm, oop obj) {
   InstanceKlass_OOP_MAP_REVERSE_ITERATE( \
     obj, \
     if (PSScavenge::should_scavenge(p)) { \
       pm->claim_or_forward_depth(p); \
     }, \
     assert_nothing )
 }
 int instanceKlass::oop_update_pointers(ParCompactionManager* cm, oop obj) {
   InstanceKlass_OOP_MAP_ITERATE( \
     obj, \
     PSParallelCompact::adjust_pointer(p), \
     assert_nothing)
   return size_helper();
 }
 void instanceKlass::push_static_fields(PSPromotionManager* pm) {
   InstanceKlass_OOP_ITERATE( \
     start_of_static_fields(), static_oop_field_size(), \
     if (PSScavenge::should_scavenge(p)) { \
       pm->claim_or_forward_depth(p); \
     }, \
     assert_nothing )
 }
 void instanceKlass::copy_static_fields(ParCompactionManager* cm) {
   InstanceKlass_OOP_ITERATE( \
     start_of_static_fields(), static_oop_field_size(), \
     PSParallelCompact::adjust_pointer(p), \
     assert_is_in)
 }
 #endif // SERIALGC
 // This klass is alive but the implementor link is not followed/updated.
 // Subklass and sibling links are handled by Klass::follow_weak_klass_links
 void instanceKlass::follow_weak_klass_links(
   BoolObjectClosure* is_alive, OopClosure* keep_alive) {
   assert(is_alive->do_object_b(as_klassOop()), "this oop should be live");
   if (ClassUnloading) {
     for (int i = 0; i < implementors_limit; i++) {
       klassOop impl = _implementors[i];
       if (impl == NULL)  break;  // no more in the list
       if (!is_alive->do_object_b(impl)) {
         // remove this guy from the list by overwriting him with the tail
         int lasti = --_nof_implementors;
         assert(lasti >= i && lasti < implementors_limit, "just checking");
         _implementors[i] = _implementors[lasti];
         _implementors[lasti] = NULL;
         --i; // rerun the loop at this index
       }
     }
   } else {
     for (int i = 0; i < implementors_limit; i++) {
       keep_alive->do_oop(&adr_implementors()[i]);
     }
   }
   Klass::follow_weak_klass_links(is_alive, keep_alive);
 }
 void instanceKlass::remove_unshareable_info() {
   Klass::remove_unshareable_info();
   init_implementor();
 }
 static void clear_all_breakpoints(methodOop m) {
   m->clear_all_breakpoints();
 }
 void instanceKlass::release_C_heap_structures() {
   // Deallocate oop map cache
   if (_oop_map_cache != NULL) {
     delete _oop_map_cache;
     _oop_map_cache = NULL;
   }
   // Deallocate JNI identifiers for jfieldIDs
   JNIid::deallocate(jni_ids());
   set_jni_ids(NULL);
   jmethodID* jmeths = methods_jmethod_ids_acquire();
   if (jmeths != (jmethodID*)NULL) {
     release_set_methods_jmethod_ids(NULL);
     FreeHeap(jmeths);
   }
   int* indices = methods_cached_itable_indices_acquire();
   if (indices != (int*)NULL) {
     release_set_methods_cached_itable_indices(NULL);
     FreeHeap(indices);
   }
   // release dependencies
   nmethodBucket* b = _dependencies;
   _dependencies = NULL;
   while (b != NULL) {
     nmethodBucket* next = b->next();
     delete b;
     b = next;
   }
   // Deallocate breakpoint records
   if (breakpoints() != 0x0) {
     methods_do(clear_all_breakpoints);
     assert(breakpoints() == 0x0, "should have cleared breakpoints");
   }
   // deallocate information about previous versions
   if (_previous_versions != NULL) {
     for (int i = _previous_versions->length() - 1; i >= 0; i--) {
       PreviousVersionNode * pv_node = _previous_versions->at(i);
       delete pv_node;
     }
     delete _previous_versions;
     _previous_versions = NULL;
   }
   // deallocate the cached class file
   if (_cached_class_file_bytes != NULL) {
     os::free(_cached_class_file_bytes);
     _cached_class_file_bytes = NULL;
     _cached_class_file_len = 0;
   }
   // Decrement symbol reference counts associated with the unloaded class.
   if (_name != NULL) _name->decrement_refcount();
   // unreference array name derived from this class name (arrays of an unloaded
   // class can't be referenced anymore).
   if (_array_name != NULL)  _array_name->decrement_refcount();
   if (_source_file_name != NULL) _source_file_name->decrement_refcount();
   if (_source_debug_extension != NULL) _source_debug_extension->decrement_refcount();
   // walk constant pool and decrement symbol reference counts
   _constants->unreference_symbols();
 }
 void instanceKlass::set_source_file_name(Symbol* n) {
   _source_file_name = n;
   if (_source_file_name != NULL) _source_file_name->increment_refcount();
 }
 void instanceKlass::set_source_debug_extension(Symbol* n) {
   _source_debug_extension = n;
   if (_source_debug_extension != NULL) _source_debug_extension->increment_refcount();
 }
 const char* instanceKlass::signature_name() const {
   const char* src = (const char*) (name()->as_C_string());
   const int src_length = (int)strlen(src);
   char* dest = NEW_RESOURCE_ARRAY(char, src_length + 3);
   int src_index = 0;
   int dest_index = 0;
   dest[dest_index++] = 'L';
   while (src_index < src_length) {
     dest[dest_index++] = src[src_index++];
   }
   dest[dest_index++] = ';';
   dest[dest_index] = '\0';
   return dest;
 }
 // different verisons of is_same_class_package
 bool instanceKlass::is_same_class_package(klassOop class2) {
   klassOop class1 = as_klassOop();
   oop classloader1 = instanceKlass::cast(class1)->class_loader();
   Symbol* classname1 = Klass::cast(class1)->name();
   if (Klass::cast(class2)->oop_is_objArray()) {
     class2 = objArrayKlass::cast(class2)->bottom_klass();
   }
   oop classloader2;
   if (Klass::cast(class2)->oop_is_instance()) {
     classloader2 = instanceKlass::cast(class2)->class_loader();
   } else {
     assert(Klass::cast(class2)->oop_is_typeArray(), "should be type array");
     classloader2 = NULL;
   }
   Symbol* classname2 = Klass::cast(class2)->name();
   return instanceKlass::is_same_class_package(classloader1, classname1,
                                               classloader2, classname2);
 }
 bool instanceKlass::is_same_class_package(oop classloader2, Symbol* classname2) {
   klassOop class1 = as_klassOop();
   oop classloader1 = instanceKlass::cast(class1)->class_loader();
   Symbol* classname1 = Klass::cast(class1)->name();
   return instanceKlass::is_same_class_package(classloader1, classname1,
                                               classloader2, classname2);
 }
 // return true if two classes are in the same package, classloader
 // and classname information is enough to determine a class's package
 bool instanceKlass::is_same_class_package(oop class_loader1, Symbol* class_name1,
                                           oop class_loader2, Symbol* class_name2) {
   if (class_loader1 != class_loader2) {
     return false;
   } else if (class_name1 == class_name2) {
     return true;                // skip painful bytewise comparison
   } else {
     ResourceMark rm;
     // The Symbol*'s are in UTF8 encoding. Since we only need to check explicitly
     // for ASCII characters ('/', 'L', '['), we can keep them in UTF8 encoding.
     // Otherwise, we just compare jbyte values between the strings.
     const jbyte *name1 = class_name1->base();
     const jbyte *name2 = class_name2->base();
     const jbyte *last_slash1 = UTF8::strrchr(name1, class_name1->utf8_length(), '/');
     const jbyte *last_slash2 = UTF8::strrchr(name2, class_name2->utf8_length(), '/');
     if ((last_slash1 == NULL) || (last_slash2 == NULL)) {
       // One of the two doesn't have a package.  Only return true
       // if the other one also doesn't have a package.
       return last_slash1 == last_slash2;
     } else {
       // Skip over '['s
       if (*name1 == '[') {
         do {
           name1++;
         } while (*name1 == '[');
         if (*name1 != 'L') {
           // Something is terribly wrong.  Shouldn't be here.
           return false;
         }
       }
       if (*name2 == '[') {
         do {
           name2++;
         } while (*name2 == '[');
         if (*name2 != 'L') {
           // Something is terribly wrong.  Shouldn't be here.
           return false;
         }
       }
       // Check that package part is identical
       int length1 = last_slash1 - name1;
       int length2 = last_slash2 - name2;
       return UTF8::equal(name1, length1, name2, length2);
     }
   }
 }
 // Returns true iff super_method can be overridden by a method in targetclassname
 // See JSL 3rd edition 8.4.6.1
 // Assumes name-signature match
 // "this" is instanceKlass of super_method which must exist
 // note that the instanceKlass of the method in the targetclassname has not always been created yet
 bool instanceKlass::is_override(methodHandle super_method, Handle targetclassloader, Symbol* targetclassname, TRAPS) {
    // Private methods can not be overridden
    if (super_method->is_private()) {
      return false;
    }
    // If super method is accessible, then override
    if ((super_method->is_protected()) ||
        (super_method->is_public())) {
      return true;
    }
    // Package-private methods are not inherited outside of package
    assert(super_method->is_package_private(), "must be package private");
    return(is_same_class_package(targetclassloader(), targetclassname));
 }
 /* defined for now in jvm.cpp, for historical reasons *--
 klassOop instanceKlass::compute_enclosing_class_impl(instanceKlassHandle self,
                                                      Symbol*& simple_name_result, TRAPS) {
   ...
 }
 */
 // tell if two classes have the same enclosing class (at package level)
 bool instanceKlass::is_same_package_member_impl(instanceKlassHandle class1,
                                                 klassOop class2_oop, TRAPS) {
   if (class2_oop == class1->as_klassOop())          return true;
   if (!Klass::cast(class2_oop)->oop_is_instance())  return false;
   instanceKlassHandle class2(THREAD, class2_oop);
   // must be in same package before we try anything else
   if (!class1->is_same_class_package(class2->class_loader(), class2->name()))
     return false;
   // As long as there is an outer1.getEnclosingClass,
   // shift the search outward.
   instanceKlassHandle outer1 = class1;
   for (;;) {
     // As we walk along, look for equalities between outer1 and class2.
     // Eventually, the walks will terminate as outer1 stops
     // at the top-level class around the original class.
     bool ignore_inner_is_member;
     klassOop next = outer1->compute_enclosing_class(&ignore_inner_is_member,
                                                     CHECK_false);
     if (next == NULL)  break;
     if (next == class2())  return true;
     outer1 = instanceKlassHandle(THREAD, next);
   }
   // Now do the same for class2.
   instanceKlassHandle outer2 = class2;
   for (;;) {
     bool ignore_inner_is_member;
     klassOop next = outer2->compute_enclosing_class(&ignore_inner_is_member,
                                                     CHECK_false);
     if (next == NULL)  break;
     // Might as well check the new outer against all available values.
     if (next == class1())  return true;
     if (next == outer1())  return true;
     outer2 = instanceKlassHandle(THREAD, next);
   }
   // If by this point we have not found an equality between the
   // two classes, we know they are in separate package members.
   return false;
 }
 jint instanceKlass::compute_modifier_flags(TRAPS) const {
   klassOop k = as_klassOop();
   jint access = access_flags().as_int();
   // But check if it happens to be member class.
   typeArrayOop inner_class_list = inner_classes();
   int length = (inner_class_list == NULL) ? 0 : inner_class_list->length();
   assert (length % instanceKlass::inner_class_next_offset == 0, "just checking");
   if (length > 0) {
     typeArrayHandle inner_class_list_h(THREAD, inner_class_list);
     instanceKlassHandle ik(THREAD, k);
     for (int i = 0; i < length; i += instanceKlass::inner_class_next_offset) {
       int ioff = inner_class_list_h->ushort_at(
                       i + instanceKlass::inner_class_inner_class_info_offset);
       // Inner class attribute can be zero, skip it.
       // Strange but true:  JVM spec. allows null inner class refs.
       if (ioff == 0) continue;
       // only look at classes that are already loaded
       // since we are looking for the flags for our self.
       Symbol* inner_name = ik->constants()->klass_name_at(ioff);
       if ((ik->name() == inner_name)) {
         // This is really a member class.
         access = inner_class_list_h->ushort_at(i + instanceKlass::inner_class_access_flags_offset);
         break;
       }
     }
   }
   // Remember to strip ACC_SUPER bit
   return (access & (~JVM_ACC_SUPER)) & JVM_ACC_WRITTEN_FLAGS;
 }
 jint instanceKlass::jvmti_class_status() const {
   jint result = 0;
   if (is_linked()) {
     result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED;
   }
   if (is_initialized()) {
     assert(is_linked(), "Class status is not consistent");
     result |= JVMTI_CLASS_STATUS_INITIALIZED;
   }
   if (is_in_error_state()) {
     result |= JVMTI_CLASS_STATUS_ERROR;
   }
   return result;
 }
 methodOop instanceKlass::method_at_itable(klassOop holder, int index, TRAPS) {
   itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
   int method_table_offset_in_words = ioe->offset()/wordSize;
   int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words())
                        / itableOffsetEntry::size();
   for (int cnt = 0 ; ; cnt ++, ioe ++) {
     // If the interface isn't implemented by the receiver class,
     // the VM should throw IncompatibleClassChangeError.
     if (cnt >= nof_interfaces) {
       THROW_0(vmSymbols::java_lang_IncompatibleClassChangeError());
     }
     klassOop ik = ioe->interface_klass();
     if (ik == holder) break;
   }
   itableMethodEntry* ime = ioe->first_method_entry(as_klassOop());
   methodOop m = ime[index].method();
   if (m == NULL) {
     THROW_0(vmSymbols::java_lang_AbstractMethodError());
   }
   return m;
 }
 // On-stack replacement stuff
 void instanceKlass::add_osr_nmethod(nmethod* n) {
   // only one compilation can be active
   NEEDS_CLEANUP
   // This is a short non-blocking critical region, so the no safepoint check is ok.
   OsrList_lock->lock_without_safepoint_check();
   assert(n->is_osr_method(), "wrong kind of nmethod");
   n->set_osr_link(osr_nmethods_head());
   set_osr_nmethods_head(n);
   // Raise the highest osr level if necessary
   if (TieredCompilation) {
     methodOop m = n->method();
     m->set_highest_osr_comp_level(MAX2(m->highest_osr_comp_level(), n->comp_level()));
   }
   // Remember to unlock again
   OsrList_lock->unlock();
   // Get rid of the osr methods for the same bci that have lower levels.
   if (TieredCompilation) {
     for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) {
       nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true);
       if (inv != NULL && inv->is_in_use()) {
         inv->make_not_entrant();
       }
     }
   }
 }
 void instanceKlass::remove_osr_nmethod(nmethod* n) {
   // This is a short non-blocking critical region, so the no safepoint check is ok.
   OsrList_lock->lock_without_safepoint_check();
   assert(n->is_osr_method(), "wrong kind of nmethod");
   nmethod* last = NULL;
   nmethod* cur  = osr_nmethods_head();
   int max_level = CompLevel_none;  // Find the max comp level excluding n
   methodOop m = n->method();
   // Search for match
   while(cur != NULL && cur != n) {
     if (TieredCompilation) {
       // Find max level before n
       max_level = MAX2(max_level, cur->comp_level());
     }
     last = cur;
     cur = cur->osr_link();
   }
   nmethod* next = NULL;
   if (cur == n) {
     next = cur->osr_link();
     if (last == NULL) {
       // Remove first element
       set_osr_nmethods_head(next);
     } else {
       last->set_osr_link(next);
     }
   }
   n->set_osr_link(NULL);
   if (TieredCompilation) {
     cur = next;
     while (cur != NULL) {
       // Find max level after n
       max_level = MAX2(max_level, cur->comp_level());
       cur = cur->osr_link();
     }
     m->set_highest_osr_comp_level(max_level);
   }
   // Remember to unlock again
   OsrList_lock->unlock();
 }
 nmethod* instanceKlass::lookup_osr_nmethod(const methodOop m, int bci, int comp_level, bool match_level) const {
   // This is a short non-blocking critical region, so the no safepoint check is ok.
   OsrList_lock->lock_without_safepoint_check();
   nmethod* osr = osr_nmethods_head();
   nmethod* best = NULL;
   while (osr != NULL) {
     assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
     // There can be a time when a c1 osr method exists but we are waiting
     // for a c2 version. When c2 completes its osr nmethod we will trash
     // the c1 version and only be able to find the c2 version. However
     // while we overflow in the c1 code at back branches we don't want to
     // try and switch to the same code as we are already running
     if (osr->method() == m &&
         (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) {
       if (match_level) {
         if (osr->comp_level() == comp_level) {
           // Found a match - return it.
           OsrList_lock->unlock();
           return osr;
         }
       } else {
         if (best == NULL || (osr->comp_level() > best->comp_level())) {
           if (osr->comp_level() == CompLevel_highest_tier) {
             // Found the best possible - return it.
             OsrList_lock->unlock();
             return osr;
           }
           best = osr;
         }
       }
     }
     osr = osr->osr_link();
   }
   OsrList_lock->unlock();
   if (best != NULL && best->comp_level() >= comp_level && match_level == false) {
     return best;
   }
   return NULL;
 }
 // -----------------------------------------------------------------------------------------------------
 #ifndef PRODUCT
 // Printing
 #define BULLET  " - "
 void FieldPrinter::do_field(fieldDescriptor* fd) {
   _st->print(BULLET);
    if (fd->is_static() || (_obj == NULL)) {
      fd->print_on(_st);
      _st->cr();
    } else {
      fd->print_on_for(_st, _obj);
      _st->cr();
    }
 }
 void instanceKlass::oop_print_on(oop obj, outputStream* st) {
   Klass::oop_print_on(obj, st);
   if (as_klassOop() == SystemDictionary::String_klass()) {
     typeArrayOop value  = java_lang_String::value(obj);
     juint        offset = java_lang_String::offset(obj);
     juint        length = java_lang_String::length(obj);
     if (value != NULL &&
         value->is_typeArray() &&
         offset          <= (juint) value->length() &&
         offset + length <= (juint) value->length()) {
       st->print(BULLET"string: ");
       Handle h_obj(obj);
       java_lang_String::print(h_obj, st);
       st->cr();
       if (!WizardMode)  return;  // that is enough
     }
   }
   st->print_cr(BULLET"---- fields (total size %d words):", oop_size(obj));
   FieldPrinter print_nonstatic_field(st, obj);
   do_nonstatic_fields(&print_nonstatic_field);
   if (as_klassOop() == SystemDictionary::Class_klass()) {
     st->print(BULLET"signature: ");
     java_lang_Class::print_signature(obj, st);
     st->cr();
     klassOop mirrored_klass = java_lang_Class::as_klassOop(obj);
     st->print(BULLET"fake entry for mirror: ");
     mirrored_klass->print_value_on(st);
     st->cr();
     st->print(BULLET"fake entry resolved_constructor: ");
     methodOop ctor = java_lang_Class::resolved_constructor(obj);
     ctor->print_value_on(st);
     klassOop array_klass = java_lang_Class::array_klass(obj);
     st->cr();
     st->print(BULLET"fake entry for array: ");
     array_klass->print_value_on(st);
     st->cr();
   } else if (as_klassOop() == SystemDictionary::MethodType_klass()) {
     st->print(BULLET"signature: ");
     java_lang_invoke_MethodType::print_signature(obj, st);
     st->cr();
   }
 }
 #endif //PRODUCT
 void instanceKlass::oop_print_value_on(oop obj, outputStream* st) {
   st->print("a ");
   name()->print_value_on(st);
   obj->print_address_on(st);
   if (as_klassOop() == SystemDictionary::String_klass()
       && java_lang_String::value(obj) != NULL) {
     ResourceMark rm;
     int len = java_lang_String::length(obj);
     int plen = (len < 24 ? len : 12);
     char* str = java_lang_String::as_utf8_string(obj, 0, plen);
     st->print(" = \"%s\"", str);
     if (len > plen)
       st->print("...[%d]", len);
   } else if (as_klassOop() == SystemDictionary::Class_klass()) {
     klassOop k = java_lang_Class::as_klassOop(obj);
     st->print(" = ");
     if (k != NULL) {
       k->print_value_on(st);
     } else {
       const char* tname = type2name(java_lang_Class::primitive_type(obj));
       st->print("%s", tname ? tname : "type?");
     }
   } else if (as_klassOop() == SystemDictionary::MethodType_klass()) {
     st->print(" = ");
     java_lang_invoke_MethodType::print_signature(obj, st);
   } else if (java_lang_boxing_object::is_instance(obj)) {
     st->print(" = ");
     java_lang_boxing_object::print(obj, st);
   }
 }
 const char* instanceKlass::internal_name() const {
   return external_name();
 }
 // Verification
 class VerifyFieldClosure: public OopClosure {
  protected:
   template <class T> void do_oop_work(T* p) {
     guarantee(Universe::heap()->is_in_closed_subset(p), "should be in heap");
     oop obj = oopDesc::load_decode_heap_oop(p);
     if (!obj->is_oop_or_null()) {
       tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p, (address)obj);
       Universe::print();
       guarantee(false, "boom");
     }
   }
  public:
   virtual void do_oop(oop* p)       { VerifyFieldClosure::do_oop_work(p); }
   virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); }
 };
 void instanceKlass::oop_verify_on(oop obj, outputStream* st) {
   Klass::oop_verify_on(obj, st);
   VerifyFieldClosure blk;
   oop_oop_iterate(obj, &blk);
 }
 #ifndef PRODUCT
 void instanceKlass::verify_class_klass_nonstatic_oop_maps(klassOop k) {
   // This verification code is disabled.  JDK_Version::is_gte_jdk14x_version()
   // cannot be called since this function is called before the VM is
   // able to determine what JDK version is running with.
   // The check below always is false since 1.4.
   return;
   // This verification code temporarily disabled for the 1.4
   // reflection implementation since java.lang.Class now has
   // Java-level instance fields. Should rewrite this to handle this
   // case.
   if (!(JDK_Version::is_gte_jdk14x_version() && UseNewReflection)) {
     // Verify that java.lang.Class instances have a fake oop field added.
     instanceKlass* ik = instanceKlass::cast(k);
     // Check that we have the right class
     static bool first_time = true;
     guarantee(k == SystemDictionary::Class_klass() && first_time, "Invalid verify of maps");
     first_time = false;
     const int extra = java_lang_Class::number_of_fake_oop_fields;
     guarantee(ik->nonstatic_field_size() == extra, "just checking");
     guarantee(ik->nonstatic_oop_map_count() == 1, "just checking");
     guarantee(ik->size_helper() == align_object_size(instanceOopDesc::header_size() + extra), "just checking");
     // Check that the map is (2,extra)
     int offset = java_lang_Class::klass_offset;
     OopMapBlock* map = ik->start_of_nonstatic_oop_maps();
     guarantee(map->offset() == offset && map->count() == (unsigned int) extra,
               "sanity");
   }
 }
 #endif // ndef PRODUCT
 // JNIid class for jfieldIDs only
 // Note to reviewers:
 // These JNI functions are just moved over to column 1 and not changed
 // in the compressed oops workspace.
 JNIid::JNIid(klassOop holder, int offset, JNIid* next) {
   _holder = holder;
   _offset = offset;
   _next = next;
   debug_only(_is_static_field_id = false;)
 }
 JNIid* JNIid::find(int offset) {
   JNIid* current = this;
   while (current != NULL) {
     if (current->offset() == offset) return current;
     current = current->next();
   }
   return NULL;
 }
 void JNIid::oops_do(OopClosure* f) {
   for (JNIid* cur = this; cur != NULL; cur = cur->next()) {
     f->do_oop(cur->holder_addr());
   }
 }
 void JNIid::deallocate(JNIid* current) {
   while (current != NULL) {
     JNIid* next = current->next();
     delete current;
     current = next;
   }
 }
 void JNIid::verify(klassOop holder) {
   int first_field_offset  = instanceKlass::cast(holder)->offset_of_static_fields();
   int end_field_offset;
   end_field_offset = first_field_offset + (instanceKlass::cast(holder)->static_field_size() * wordSize);
   JNIid* current = this;
   while (current != NULL) {
     guarantee(current->holder() == holder, "Invalid klass in JNIid");
 #ifdef ASSERT
     int o = current->offset();
     if (current->is_static_field_id()) {
       guarantee(o >= first_field_offset  && o < end_field_offset,  "Invalid static field offset in JNIid");
     }
 #endif
     current = current->next();
   }
 }
 #ifdef ASSERT
 void instanceKlass::set_init_state(ClassState state) {
   bool good_state = as_klassOop()->is_shared() ? (_init_state <= state)
                                                : (_init_state < state);
   assert(good_state || state == allocated, "illegal state transition");
   _init_state = state;
 }
 #endif
 // RedefineClasses() support for previous versions:
 // Add an information node that contains weak references to the
 // interesting parts of the previous version of the_class.
 // This is also where we clean out any unused weak references.
 // Note that while we delete nodes from the _previous_versions
 // array, we never delete the array itself until the klass is
 // unloaded. The has_been_redefined() query depends on that fact.
 //
 void instanceKlass::add_previous_version(instanceKlassHandle ikh,
        BitMap* emcp_methods, int emcp_method_count) {
   assert(Thread::current()->is_VM_thread(),
          "only VMThread can add previous versions");
   if (_previous_versions == NULL) {
     // This is the first previous version so make some space.
     // Start with 2 elements under the assumption that the class
     // won't be redefined much.
     _previous_versions =  new (ResourceObj::C_HEAP)
                             GrowableArray<PreviousVersionNode *>(2, true);
   }
   // RC_TRACE macro has an embedded ResourceMark
   RC_TRACE(0x00000100, ("adding previous version ref for %s @%d, EMCP_cnt=%d",
     ikh->external_name(), _previous_versions->length(), emcp_method_count));
   constantPoolHandle cp_h(ikh->constants());
   jobject cp_ref;
   if (cp_h->is_shared()) {
     // a shared ConstantPool requires a regular reference; a weak
     // reference would be collectible
     cp_ref = JNIHandles::make_global(cp_h);
   } else {
     cp_ref = JNIHandles::make_weak_global(cp_h);
   }
   PreviousVersionNode * pv_node = NULL;
   objArrayOop old_methods = ikh->methods();
   if (emcp_method_count == 0) {
     // non-shared ConstantPool gets a weak reference
     pv_node = new PreviousVersionNode(cp_ref, !cp_h->is_shared(), NULL);
     RC_TRACE(0x00000400,
       ("add: all methods are obsolete; flushing any EMCP weak refs"));
   } else {
     int local_count = 0;
     GrowableArray<jweak>* method_refs = new (ResourceObj::C_HEAP)
       GrowableArray<jweak>(emcp_method_count, true);
     for (int i = 0; i < old_methods->length(); i++) {
       if (emcp_methods->at(i)) {
         // this old method is EMCP so save a weak ref
         methodOop old_method = (methodOop) old_methods->obj_at(i);
         methodHandle old_method_h(old_method);
         jweak method_ref = JNIHandles::make_weak_global(old_method_h);
         method_refs->append(method_ref);
         if (++local_count >= emcp_method_count) {
           // no more EMCP methods so bail out now
           break;
         }
       }
     }
     // non-shared ConstantPool gets a weak reference
     pv_node = new PreviousVersionNode(cp_ref, !cp_h->is_shared(), method_refs);
   }
   _previous_versions->append(pv_node);
   // Using weak references allows the interesting parts of previous
   // classes to be GC'ed when they are no longer needed. Since the
   // caller is the VMThread and we are at a safepoint, this is a good
   // time to clear out unused weak references.
   RC_TRACE(0x00000400, ("add: previous version length=%d",
     _previous_versions->length()));
   // skip the last entry since we just added it
   for (int i = _previous_versions->length() - 2; i >= 0; i--) {
     // check the previous versions array for a GC'ed weak refs
     pv_node = _previous_versions->at(i);
     cp_ref = pv_node->prev_constant_pool();
     assert(cp_ref != NULL, "cp ref was unexpectedly cleared");
     if (cp_ref == NULL) {
       delete pv_node;
       _previous_versions->remove_at(i);
       // Since we are traversing the array backwards, we don't have to
       // do anything special with the index.
       continue;  // robustness
     }
     constantPoolOop cp = (constantPoolOop)JNIHandles::resolve(cp_ref);
     if (cp == NULL) {
       // this entry has been GC'ed so remove it
       delete pv_node;
       _previous_versions->remove_at(i);
       // Since we are traversing the array backwards, we don't have to
       // do anything special with the index.
       continue;
     } else {
       RC_TRACE(0x00000400, ("add: previous version @%d is alive", i));
     }
     GrowableArray<jweak>* method_refs = pv_node->prev_EMCP_methods();
     if (method_refs != NULL) {
       RC_TRACE(0x00000400, ("add: previous methods length=%d",
         method_refs->length()));
       for (int j = method_refs->length() - 1; j >= 0; j--) {
         jweak method_ref = method_refs->at(j);
         assert(method_ref != NULL, "weak method ref was unexpectedly cleared");
         if (method_ref == NULL) {
           method_refs->remove_at(j);
           // Since we are traversing the array backwards, we don't have to
           // do anything special with the index.
           continue;  // robustness
         }
         methodOop method = (methodOop)JNIHandles::resolve(method_ref);
         if (method == NULL || emcp_method_count == 0) {
           // This method entry has been GC'ed or the current
           // RedefineClasses() call has made all methods obsolete
           // so remove it.
           JNIHandles::destroy_weak_global(method_ref);
           method_refs->remove_at(j);
         } else {
           // RC_TRACE macro has an embedded ResourceMark
           RC_TRACE(0x00000400,
             ("add: %s(%s): previous method @%d in version @%d is alive",
             method->name()->as_C_string(), method->signature()->as_C_string(),
             j, i));
         }
       }
     }
   }
   int obsolete_method_count = old_methods->length() - emcp_method_count;
   if (emcp_method_count != 0 && obsolete_method_count != 0 &&
       _previous_versions->length() > 1) {
     // We have a mix of obsolete and EMCP methods. If there is more
     // than the previous version that we just added, then we have to
     // clear out any matching EMCP method entries the hard way.
     int local_count = 0;
     for (int i = 0; i < old_methods->length(); i++) {
       if (!emcp_methods->at(i)) {
         // only obsolete methods are interesting
         methodOop old_method = (methodOop) old_methods->obj_at(i);
         Symbol* m_name = old_method->name();
         Symbol* m_signature = old_method->signature();
         // skip the last entry since we just added it
         for (int j = _previous_versions->length() - 2; j >= 0; j--) {
           // check the previous versions array for a GC'ed weak refs
           pv_node = _previous_versions->at(j);
           cp_ref = pv_node->prev_constant_pool();
           assert(cp_ref != NULL, "cp ref was unexpectedly cleared");
           if (cp_ref == NULL) {
             delete pv_node;
             _previous_versions->remove_at(j);
             // Since we are traversing the array backwards, we don't have to
             // do anything special with the index.
             continue;  // robustness
           }
           constantPoolOop cp = (constantPoolOop)JNIHandles::resolve(cp_ref);
           if (cp == NULL) {
             // this entry has been GC'ed so remove it
             delete pv_node;
             _previous_versions->remove_at(j);
             // Since we are traversing the array backwards, we don't have to
             // do anything special with the index.
             continue;
           }
           GrowableArray<jweak>* method_refs = pv_node->prev_EMCP_methods();
           if (method_refs == NULL) {
             // We have run into a PreviousVersion generation where
             // all methods were made obsolete during that generation's
             // RedefineClasses() operation. At the time of that
             // operation, all EMCP methods were flushed so we don't
             // have to go back any further.
             //
             // A NULL method_refs is different than an empty method_refs.
             // We cannot infer any optimizations about older generations
             // from an empty method_refs for the current generation.
             break;
           }
           for (int k = method_refs->length() - 1; k >= 0; k--) {
             jweak method_ref = method_refs->at(k);
             assert(method_ref != NULL,
               "weak method ref was unexpectedly cleared");
             if (method_ref == NULL) {
               method_refs->remove_at(k);
               // Since we are traversing the array backwards, we don't
               // have to do anything special with the index.
               continue;  // robustness
             }
             methodOop method = (methodOop)JNIHandles::resolve(method_ref);
             if (method == NULL) {
               // this method entry has been GC'ed so skip it
               JNIHandles::destroy_weak_global(method_ref);
               method_refs->remove_at(k);
               continue;
             }
             if (method->name() == m_name &&
                 method->signature() == m_signature) {
               // The current RedefineClasses() call has made all EMCP
               // versions of this method obsolete so mark it as obsolete
               // and remove the weak ref.
               RC_TRACE(0x00000400,
                 ("add: %s(%s): flush obsolete method @%d in version @%d",
                 m_name->as_C_string(), m_signature->as_C_string(), k, j));
               method->set_is_obsolete();
               JNIHandles::destroy_weak_global(method_ref);
               method_refs->remove_at(k);
               break;
             }
           }
           // The previous loop may not find a matching EMCP method, but
           // that doesn't mean that we can optimize and not go any
           // further back in the PreviousVersion generations. The EMCP
           // method for this generation could have already been GC'ed,
           // but there still may be an older EMCP method that has not
           // been GC'ed.
         }
         if (++local_count >= obsolete_method_count) {
           // no more obsolete methods so bail out now
           break;
         }
       }
     }
   }
 } // end add_previous_version()
 // Determine if instanceKlass has a previous version.
 bool instanceKlass::has_previous_version() const {
   if (_previous_versions == NULL) {
     // no previous versions array so answer is easy
     return false;
   }
   for (int i = _previous_versions->length() - 1; i >= 0; i--) {
     // Check the previous versions array for an info node that hasn't
     // been GC'ed
     PreviousVersionNode * pv_node = _previous_versions->at(i);
     jobject cp_ref = pv_node->prev_constant_pool();
     assert(cp_ref != NULL, "cp reference was unexpectedly cleared");
     if (cp_ref == NULL) {
       continue;  // robustness
     }
     constantPoolOop cp = (constantPoolOop)JNIHandles::resolve(cp_ref);
     if (cp != NULL) {
       // we have at least one previous version
       return true;
     }
     // We don't have to check the method refs. If the constant pool has
     // been GC'ed then so have the methods.
   }
   // all of the underlying nodes' info has been GC'ed
   return false;
 } // end has_previous_version()
 methodOop instanceKlass::method_with_idnum(int idnum) {
   methodOop m = NULL;
   if (idnum < methods()->length()) {
     m = (methodOop) methods()->obj_at(idnum);
   }
   if (m == NULL || m->method_idnum() != idnum) {
     for (int index = 0; index < methods()->length(); ++index) {
       m = (methodOop) methods()->obj_at(index);
       if (m->method_idnum() == idnum) {
         return m;
       }
     }
   }
   return m;
 }
 // Set the annotation at 'idnum' to 'anno'.
 // We don't want to create or extend the array if 'anno' is NULL, since that is the
 // default value.  However, if the array exists and is long enough, we must set NULL values.
 void instanceKlass::set_methods_annotations_of(int idnum, typeArrayOop anno, objArrayOop* md_p) {
   objArrayOop md = *md_p;
   if (md != NULL && md->length() > idnum) {
     md->obj_at_put(idnum, anno);
   } else if (anno != NULL) {
     // create the array
     int length = MAX2(idnum+1, (int)_idnum_allocated_count);
     md = oopFactory::new_system_objArray(length, Thread::current());
     if (*md_p != NULL) {
       // copy the existing entries
       for (int index = 0; index < (*md_p)->length(); index++) {
         md->obj_at_put(index, (*md_p)->obj_at(index));
       }
     }
     set_annotations(md, md_p);
     md->obj_at_put(idnum, anno);
   } // if no array and idnum isn't included there is nothing to do
 }
 // Construct a PreviousVersionNode entry for the array hung off
 // the instanceKlass.
 PreviousVersionNode::PreviousVersionNode(jobject prev_constant_pool,
   bool prev_cp_is_weak, GrowableArray<jweak>* prev_EMCP_methods) {
   _prev_constant_pool = prev_constant_pool;
   _prev_cp_is_weak = prev_cp_is_weak;
   _prev_EMCP_methods = prev_EMCP_methods;
 }
 // Destroy a PreviousVersionNode
 PreviousVersionNode::~PreviousVersionNode() {
   if (_prev_constant_pool != NULL) {
     if (_prev_cp_is_weak) {
       JNIHandles::destroy_weak_global(_prev_constant_pool);
     } else {
       JNIHandles::destroy_global(_prev_constant_pool);
     }
   }
   if (_prev_EMCP_methods != NULL) {
     for (int i = _prev_EMCP_methods->length() - 1; i >= 0; i--) {
       jweak method_ref = _prev_EMCP_methods->at(i);
       if (method_ref != NULL) {
         JNIHandles::destroy_weak_global(method_ref);
       }
     }
     delete _prev_EMCP_methods;
   }
 }
 // Construct a PreviousVersionInfo entry
 PreviousVersionInfo::PreviousVersionInfo(PreviousVersionNode *pv_node) {
   _prev_constant_pool_handle = constantPoolHandle();  // NULL handle
   _prev_EMCP_method_handles = NULL;
   jobject cp_ref = pv_node->prev_constant_pool();
   assert(cp_ref != NULL, "constant pool ref was unexpectedly cleared");
   if (cp_ref == NULL) {
     return;  // robustness
   }
   constantPoolOop cp = (constantPoolOop)JNIHandles::resolve(cp_ref);
   if (cp == NULL) {
     // Weak reference has been GC'ed. Since the constant pool has been
     // GC'ed, the methods have also been GC'ed.
     return;
   }
   // make the constantPoolOop safe to return
   _prev_constant_pool_handle = constantPoolHandle(cp);
   GrowableArray<jweak>* method_refs = pv_node->prev_EMCP_methods();
   if (method_refs == NULL) {
     // the instanceKlass did not have any EMCP methods
     return;
   }
   _prev_EMCP_method_handles = new GrowableArray<methodHandle>(10);
   int n_methods = method_refs->length();
   for (int i = 0; i < n_methods; i++) {
     jweak method_ref = method_refs->at(i);
     assert(method_ref != NULL, "weak method ref was unexpectedly cleared");
     if (method_ref == NULL) {
       continue;  // robustness
     }
     methodOop method = (methodOop)JNIHandles::resolve(method_ref);
     if (method == NULL) {
       // this entry has been GC'ed so skip it
       continue;
     }
     // make the methodOop safe to return
     _prev_EMCP_method_handles->append(methodHandle(method));
   }
 }
 // Destroy a PreviousVersionInfo
 PreviousVersionInfo::~PreviousVersionInfo() {
   // Since _prev_EMCP_method_handles is not C-heap allocated, we
   // don't have to delete it.
 }
 // Construct a helper for walking the previous versions array
 PreviousVersionWalker::PreviousVersionWalker(instanceKlass *ik) {
   _previous_versions = ik->previous_versions();
   _current_index = 0;
   // _hm needs no initialization
   _current_p = NULL;
 }
 // Destroy a PreviousVersionWalker
 PreviousVersionWalker::~PreviousVersionWalker() {
   // Delete the current info just in case the caller didn't walk to
   // the end of the previous versions list. No harm if _current_p is
   // already NULL.
   delete _current_p;
   // When _hm is destroyed, all the Handles returned in
   // PreviousVersionInfo objects will be destroyed.
   // Also, after this destructor is finished it will be
   // safe to delete the GrowableArray allocated in the
   // PreviousVersionInfo objects.
 }
 // Return the interesting information for the next previous version
 // of the klass. Returns NULL if there are no more previous versions.
 PreviousVersionInfo* PreviousVersionWalker::next_previous_version() {
   if (_previous_versions == NULL) {
     // no previous versions so nothing to return
     return NULL;
   }
   delete _current_p;  // cleanup the previous info for the caller
   _current_p = NULL;  // reset to NULL so we don't delete same object twice
   int length = _previous_versions->length();
   while (_current_index < length) {
     PreviousVersionNode * pv_node = _previous_versions->at(_current_index++);
     PreviousVersionInfo * pv_info = new (ResourceObj::C_HEAP)
                                           PreviousVersionInfo(pv_node);
     constantPoolHandle cp_h = pv_info->prev_constant_pool_handle();
     if (cp_h.is_null()) {
       delete pv_info;
       // The underlying node's info has been GC'ed so try the next one.
       // We don't have to check the methods. If the constant pool has
       // GC'ed then so have the methods.
       continue;
     }
     // Found a node with non GC'ed info so return it. The caller will
     // need to delete pv_info when they are done with it.
     _current_p = pv_info;
     return pv_info;
   }
   // all of the underlying nodes' info has been GC'ed
   return NULL;
 } // end next_previous_version()

Mercurial > jdk8-mips64-public > hotspot / annotate

src/share/vm/oops/instanceKlass.cpp@8033953d67ff (annotated)

src/share/vm/oops/instanceKlass.cpp