src/share/vm/oops/instanceKlass.cpp

Fri, 24 Oct 2014 12:29:08 -0700

author
acorn
date
Fri, 24 Oct 2014 12:29:08 -0700
changeset 7290
90257dfad6e3
parent 7191
7dca5ed0e13d
child 7325
3c87c13918fb
permissions
-rw-r--r--

8043275: 8u40 backport: Fix interface initialization for default methods.
Reviewed-by: dcubed, coleenp

     1 /*
     2  * Copyright (c) 1997, 2014, Oracle and/or its affiliates. All rights reserved.
     3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
     4  *
     5  * This code is free software; you can redistribute it and/or modify it
     6  * under the terms of the GNU General Public License version 2 only, as
     7  * published by the Free Software Foundation.
     8  *
     9  * This code is distributed in the hope that it will be useful, but WITHOUT
    10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
    11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
    12  * version 2 for more details (a copy is included in the LICENSE file that
    13  * accompanied this code).
    14  *
    15  * You should have received a copy of the GNU General Public License version
    16  * 2 along with this work; if not, write to the Free Software Foundation,
    17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
    18  *
    19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
    20  * or visit www.oracle.com if you need additional information or have any
    21  * questions.
    22  *
    23  */
    25 #include "precompiled.hpp"
    26 #include "classfile/javaClasses.hpp"
    27 #include "classfile/systemDictionary.hpp"
    28 #include "classfile/verifier.hpp"
    29 #include "classfile/vmSymbols.hpp"
    30 #include "compiler/compileBroker.hpp"
    31 #include "gc_implementation/shared/markSweep.inline.hpp"
    32 #include "gc_interface/collectedHeap.inline.hpp"
    33 #include "interpreter/oopMapCache.hpp"
    34 #include "interpreter/rewriter.hpp"
    35 #include "jvmtifiles/jvmti.h"
    36 #include "memory/genOopClosures.inline.hpp"
    37 #include "memory/heapInspection.hpp"
    38 #include "memory/iterator.inline.hpp"
    39 #include "memory/metadataFactory.hpp"
    40 #include "memory/oopFactory.hpp"
    41 #include "oops/fieldStreams.hpp"
    42 #include "oops/instanceClassLoaderKlass.hpp"
    43 #include "oops/instanceKlass.hpp"
    44 #include "oops/instanceMirrorKlass.hpp"
    45 #include "oops/instanceOop.hpp"
    46 #include "oops/klass.inline.hpp"
    47 #include "oops/method.hpp"
    48 #include "oops/oop.inline.hpp"
    49 #include "oops/symbol.hpp"
    50 #include "prims/jvmtiExport.hpp"
    51 #include "prims/jvmtiRedefineClassesTrace.hpp"
    52 #include "prims/jvmtiRedefineClasses.hpp"
    53 #include "prims/methodComparator.hpp"
    54 #include "runtime/fieldDescriptor.hpp"
    55 #include "runtime/handles.inline.hpp"
    56 #include "runtime/javaCalls.hpp"
    57 #include "runtime/mutexLocker.hpp"
    58 #include "runtime/orderAccess.inline.hpp"
    59 #include "runtime/thread.inline.hpp"
    60 #include "services/classLoadingService.hpp"
    61 #include "services/threadService.hpp"
    62 #include "utilities/dtrace.hpp"
    63 #include "utilities/macros.hpp"
    64 #if INCLUDE_ALL_GCS
    65 #include "gc_implementation/concurrentMarkSweep/cmsOopClosures.inline.hpp"
    66 #include "gc_implementation/g1/g1CollectedHeap.inline.hpp"
    67 #include "gc_implementation/g1/g1OopClosures.inline.hpp"
    68 #include "gc_implementation/g1/g1RemSet.inline.hpp"
    69 #include "gc_implementation/g1/heapRegionManager.inline.hpp"
    70 #include "gc_implementation/parNew/parOopClosures.inline.hpp"
    71 #include "gc_implementation/parallelScavenge/parallelScavengeHeap.inline.hpp"
    72 #include "gc_implementation/parallelScavenge/psPromotionManager.inline.hpp"
    73 #include "gc_implementation/parallelScavenge/psScavenge.inline.hpp"
    74 #include "oops/oop.pcgc.inline.hpp"
    75 #endif // INCLUDE_ALL_GCS
    76 #ifdef COMPILER1
    77 #include "c1/c1_Compiler.hpp"
    78 #endif
    80 PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC
    82 #ifdef DTRACE_ENABLED
    84 #ifndef USDT2
    86 HS_DTRACE_PROBE_DECL4(hotspot, class__initialization__required,
    87   char*, intptr_t, oop, intptr_t);
    88 HS_DTRACE_PROBE_DECL5(hotspot, class__initialization__recursive,
    89   char*, intptr_t, oop, intptr_t, int);
    90 HS_DTRACE_PROBE_DECL5(hotspot, class__initialization__concurrent,
    91   char*, intptr_t, oop, intptr_t, int);
    92 HS_DTRACE_PROBE_DECL5(hotspot, class__initialization__erroneous,
    93   char*, intptr_t, oop, intptr_t, int);
    94 HS_DTRACE_PROBE_DECL5(hotspot, class__initialization__super__failed,
    95   char*, intptr_t, oop, intptr_t, int);
    96 HS_DTRACE_PROBE_DECL5(hotspot, class__initialization__clinit,
    97   char*, intptr_t, oop, intptr_t, int);
    98 HS_DTRACE_PROBE_DECL5(hotspot, class__initialization__error,
    99   char*, intptr_t, oop, intptr_t, int);
   100 HS_DTRACE_PROBE_DECL5(hotspot, class__initialization__end,
   101   char*, intptr_t, oop, intptr_t, int);
   103 #define DTRACE_CLASSINIT_PROBE(type, clss, thread_type)          \
   104   {                                                              \
   105     char* data = NULL;                                           \
   106     int len = 0;                                                 \
   107     Symbol* name = (clss)->name();                               \
   108     if (name != NULL) {                                          \
   109       data = (char*)name->bytes();                               \
   110       len = name->utf8_length();                                 \
   111     }                                                            \
   112     HS_DTRACE_PROBE4(hotspot, class__initialization__##type,     \
   113       data, len, SOLARIS_ONLY((void *))(clss)->class_loader(), thread_type);           \
   114   }
   116 #define DTRACE_CLASSINIT_PROBE_WAIT(type, clss, thread_type, wait) \
   117   {                                                              \
   118     char* data = NULL;                                           \
   119     int len = 0;                                                 \
   120     Symbol* name = (clss)->name();                               \
   121     if (name != NULL) {                                          \
   122       data = (char*)name->bytes();                               \
   123       len = name->utf8_length();                                 \
   124     }                                                            \
   125     HS_DTRACE_PROBE5(hotspot, class__initialization__##type,     \
   126       data, len, SOLARIS_ONLY((void *))(clss)->class_loader(), thread_type, wait);     \
   127   }
   128 #else /* USDT2 */
   130 #define HOTSPOT_CLASS_INITIALIZATION_required HOTSPOT_CLASS_INITIALIZATION_REQUIRED
   131 #define HOTSPOT_CLASS_INITIALIZATION_recursive HOTSPOT_CLASS_INITIALIZATION_RECURSIVE
   132 #define HOTSPOT_CLASS_INITIALIZATION_concurrent HOTSPOT_CLASS_INITIALIZATION_CONCURRENT
   133 #define HOTSPOT_CLASS_INITIALIZATION_erroneous HOTSPOT_CLASS_INITIALIZATION_ERRONEOUS
   134 #define HOTSPOT_CLASS_INITIALIZATION_super__failed HOTSPOT_CLASS_INITIALIZATION_SUPER_FAILED
   135 #define HOTSPOT_CLASS_INITIALIZATION_clinit HOTSPOT_CLASS_INITIALIZATION_CLINIT
   136 #define HOTSPOT_CLASS_INITIALIZATION_error HOTSPOT_CLASS_INITIALIZATION_ERROR
   137 #define HOTSPOT_CLASS_INITIALIZATION_end HOTSPOT_CLASS_INITIALIZATION_END
   138 #define DTRACE_CLASSINIT_PROBE(type, clss, thread_type)          \
   139   {                                                              \
   140     char* data = NULL;                                           \
   141     int len = 0;                                                 \
   142     Symbol* name = (clss)->name();                               \
   143     if (name != NULL) {                                          \
   144       data = (char*)name->bytes();                               \
   145       len = name->utf8_length();                                 \
   146     }                                                            \
   147     HOTSPOT_CLASS_INITIALIZATION_##type(                         \
   148       data, len, (clss)->class_loader(), thread_type);           \
   149   }
   151 #define DTRACE_CLASSINIT_PROBE_WAIT(type, clss, thread_type, wait) \
   152   {                                                              \
   153     char* data = NULL;                                           \
   154     int len = 0;                                                 \
   155     Symbol* name = (clss)->name();                               \
   156     if (name != NULL) {                                          \
   157       data = (char*)name->bytes();                               \
   158       len = name->utf8_length();                                 \
   159     }                                                            \
   160     HOTSPOT_CLASS_INITIALIZATION_##type(                         \
   161       data, len, (clss)->class_loader(), thread_type, wait);     \
   162   }
   163 #endif /* USDT2 */
   165 #else //  ndef DTRACE_ENABLED
   167 #define DTRACE_CLASSINIT_PROBE(type, clss, thread_type)
   168 #define DTRACE_CLASSINIT_PROBE_WAIT(type, clss, thread_type, wait)
   170 #endif //  ndef DTRACE_ENABLED
   172 volatile int InstanceKlass::_total_instanceKlass_count = 0;
   174 InstanceKlass* InstanceKlass::allocate_instance_klass(
   175                                               ClassLoaderData* loader_data,
   176                                               int vtable_len,
   177                                               int itable_len,
   178                                               int static_field_size,
   179                                               int nonstatic_oop_map_size,
   180                                               ReferenceType rt,
   181                                               AccessFlags access_flags,
   182                                               Symbol* name,
   183                                               Klass* super_klass,
   184                                               bool is_anonymous,
   185                                               TRAPS) {
   187   int size = InstanceKlass::size(vtable_len, itable_len, nonstatic_oop_map_size,
   188                                  access_flags.is_interface(), is_anonymous);
   190   // Allocation
   191   InstanceKlass* ik;
   192   if (rt == REF_NONE) {
   193     if (name == vmSymbols::java_lang_Class()) {
   194       ik = new (loader_data, size, THREAD) InstanceMirrorKlass(
   195         vtable_len, itable_len, static_field_size, nonstatic_oop_map_size, rt,
   196         access_flags, is_anonymous);
   197     } else if (name == vmSymbols::java_lang_ClassLoader() ||
   198           (SystemDictionary::ClassLoader_klass_loaded() &&
   199           super_klass != NULL &&
   200           super_klass->is_subtype_of(SystemDictionary::ClassLoader_klass()))) {
   201       ik = new (loader_data, size, THREAD) InstanceClassLoaderKlass(
   202         vtable_len, itable_len, static_field_size, nonstatic_oop_map_size, rt,
   203         access_flags, is_anonymous);
   204     } else {
   205       // normal class
   206       ik = new (loader_data, size, THREAD) InstanceKlass(
   207         vtable_len, itable_len, static_field_size, nonstatic_oop_map_size, rt,
   208         access_flags, is_anonymous);
   209     }
   210   } else {
   211     // reference klass
   212     ik = new (loader_data, size, THREAD) InstanceRefKlass(
   213         vtable_len, itable_len, static_field_size, nonstatic_oop_map_size, rt,
   214         access_flags, is_anonymous);
   215   }
   217   // Check for pending exception before adding to the loader data and incrementing
   218   // class count.  Can get OOM here.
   219   if (HAS_PENDING_EXCEPTION) {
   220     return NULL;
   221   }
   223   // Add all classes to our internal class loader list here,
   224   // including classes in the bootstrap (NULL) class loader.
   225   loader_data->add_class(ik);
   227   Atomic::inc(&_total_instanceKlass_count);
   228   return ik;
   229 }
   232 // copy method ordering from resource area to Metaspace
   233 void InstanceKlass::copy_method_ordering(intArray* m, TRAPS) {
   234   if (m != NULL) {
   235     // allocate a new array and copy contents (memcpy?)
   236     _method_ordering = MetadataFactory::new_array<int>(class_loader_data(), m->length(), CHECK);
   237     for (int i = 0; i < m->length(); i++) {
   238       _method_ordering->at_put(i, m->at(i));
   239     }
   240   } else {
   241     _method_ordering = Universe::the_empty_int_array();
   242   }
   243 }
   245 // create a new array of vtable_indices for default methods
   246 Array<int>* InstanceKlass::create_new_default_vtable_indices(int len, TRAPS) {
   247   Array<int>* vtable_indices = MetadataFactory::new_array<int>(class_loader_data(), len, CHECK_NULL);
   248   assert(default_vtable_indices() == NULL, "only create once");
   249   set_default_vtable_indices(vtable_indices);
   250   return vtable_indices;
   251 }
   253 InstanceKlass::InstanceKlass(int vtable_len,
   254                              int itable_len,
   255                              int static_field_size,
   256                              int nonstatic_oop_map_size,
   257                              ReferenceType rt,
   258                              AccessFlags access_flags,
   259                              bool is_anonymous) {
   260   No_Safepoint_Verifier no_safepoint; // until k becomes parsable
   262   int iksize = InstanceKlass::size(vtable_len, itable_len, nonstatic_oop_map_size,
   263                                    access_flags.is_interface(), is_anonymous);
   265   set_vtable_length(vtable_len);
   266   set_itable_length(itable_len);
   267   set_static_field_size(static_field_size);
   268   set_nonstatic_oop_map_size(nonstatic_oop_map_size);
   269   set_access_flags(access_flags);
   270   _misc_flags = 0;  // initialize to zero
   271   set_is_anonymous(is_anonymous);
   272   assert(size() == iksize, "wrong size for object");
   274   set_array_klasses(NULL);
   275   set_methods(NULL);
   276   set_method_ordering(NULL);
   277   set_default_methods(NULL);
   278   set_default_vtable_indices(NULL);
   279   set_local_interfaces(NULL);
   280   set_transitive_interfaces(NULL);
   281   init_implementor();
   282   set_fields(NULL, 0);
   283   set_constants(NULL);
   284   set_class_loader_data(NULL);
   285   set_source_file_name_index(0);
   286   set_source_debug_extension(NULL, 0);
   287   set_array_name(NULL);
   288   set_inner_classes(NULL);
   289   set_static_oop_field_count(0);
   290   set_nonstatic_field_size(0);
   291   set_is_marked_dependent(false);
   292   set_has_unloaded_dependent(false);
   293   set_init_state(InstanceKlass::allocated);
   294   set_init_thread(NULL);
   295   set_reference_type(rt);
   296   set_oop_map_cache(NULL);
   297   set_jni_ids(NULL);
   298   set_osr_nmethods_head(NULL);
   299   set_breakpoints(NULL);
   300   init_previous_versions();
   301   set_generic_signature_index(0);
   302   release_set_methods_jmethod_ids(NULL);
   303   set_annotations(NULL);
   304   set_jvmti_cached_class_field_map(NULL);
   305   set_initial_method_idnum(0);
   306   _dependencies = NULL;
   307   set_jvmti_cached_class_field_map(NULL);
   308   set_cached_class_file(NULL);
   309   set_initial_method_idnum(0);
   310   set_minor_version(0);
   311   set_major_version(0);
   312   NOT_PRODUCT(_verify_count = 0;)
   314   // initialize the non-header words to zero
   315   intptr_t* p = (intptr_t*)this;
   316   for (int index = InstanceKlass::header_size(); index < iksize; index++) {
   317     p[index] = NULL_WORD;
   318   }
   320   // Set temporary value until parseClassFile updates it with the real instance
   321   // size.
   322   set_layout_helper(Klass::instance_layout_helper(0, true));
   323 }
   326 void InstanceKlass::deallocate_methods(ClassLoaderData* loader_data,
   327                                        Array<Method*>* methods) {
   328   if (methods != NULL && methods != Universe::the_empty_method_array() &&
   329       !methods->is_shared()) {
   330     for (int i = 0; i < methods->length(); i++) {
   331       Method* method = methods->at(i);
   332       if (method == NULL) continue;  // maybe null if error processing
   333       // Only want to delete methods that are not executing for RedefineClasses.
   334       // The previous version will point to them so they're not totally dangling
   335       assert (!method->on_stack(), "shouldn't be called with methods on stack");
   336       MetadataFactory::free_metadata(loader_data, method);
   337     }
   338     MetadataFactory::free_array<Method*>(loader_data, methods);
   339   }
   340 }
   342 void InstanceKlass::deallocate_interfaces(ClassLoaderData* loader_data,
   343                                           Klass* super_klass,
   344                                           Array<Klass*>* local_interfaces,
   345                                           Array<Klass*>* transitive_interfaces) {
   346   // Only deallocate transitive interfaces if not empty, same as super class
   347   // or same as local interfaces.  See code in parseClassFile.
   348   Array<Klass*>* ti = transitive_interfaces;
   349   if (ti != Universe::the_empty_klass_array() && ti != local_interfaces) {
   350     // check that the interfaces don't come from super class
   351     Array<Klass*>* sti = (super_klass == NULL) ? NULL :
   352                     InstanceKlass::cast(super_klass)->transitive_interfaces();
   353     if (ti != sti && ti != NULL && !ti->is_shared()) {
   354       MetadataFactory::free_array<Klass*>(loader_data, ti);
   355     }
   356   }
   358   // local interfaces can be empty
   359   if (local_interfaces != Universe::the_empty_klass_array() &&
   360       local_interfaces != NULL && !local_interfaces->is_shared()) {
   361     MetadataFactory::free_array<Klass*>(loader_data, local_interfaces);
   362   }
   363 }
   365 // This function deallocates the metadata and C heap pointers that the
   366 // InstanceKlass points to.
   367 void InstanceKlass::deallocate_contents(ClassLoaderData* loader_data) {
   369   // Orphan the mirror first, CMS thinks it's still live.
   370   if (java_mirror() != NULL) {
   371     java_lang_Class::set_klass(java_mirror(), NULL);
   372   }
   374   // Need to take this class off the class loader data list.
   375   loader_data->remove_class(this);
   377   // The array_klass for this class is created later, after error handling.
   378   // For class redefinition, we keep the original class so this scratch class
   379   // doesn't have an array class.  Either way, assert that there is nothing
   380   // to deallocate.
   381   assert(array_klasses() == NULL, "array classes shouldn't be created for this class yet");
   383   // Release C heap allocated data that this might point to, which includes
   384   // reference counting symbol names.
   385   release_C_heap_structures();
   387   deallocate_methods(loader_data, methods());
   388   set_methods(NULL);
   390   if (method_ordering() != NULL &&
   391       method_ordering() != Universe::the_empty_int_array() &&
   392       !method_ordering()->is_shared()) {
   393     MetadataFactory::free_array<int>(loader_data, method_ordering());
   394   }
   395   set_method_ordering(NULL);
   397   // default methods can be empty
   398   if (default_methods() != NULL &&
   399       default_methods() != Universe::the_empty_method_array() &&
   400       !default_methods()->is_shared()) {
   401     MetadataFactory::free_array<Method*>(loader_data, default_methods());
   402   }
   403   // Do NOT deallocate the default methods, they are owned by superinterfaces.
   404   set_default_methods(NULL);
   406   // default methods vtable indices can be empty
   407   if (default_vtable_indices() != NULL &&
   408       !default_vtable_indices()->is_shared()) {
   409     MetadataFactory::free_array<int>(loader_data, default_vtable_indices());
   410   }
   411   set_default_vtable_indices(NULL);
   414   // This array is in Klass, but remove it with the InstanceKlass since
   415   // this place would be the only caller and it can share memory with transitive
   416   // interfaces.
   417   if (secondary_supers() != NULL &&
   418       secondary_supers() != Universe::the_empty_klass_array() &&
   419       secondary_supers() != transitive_interfaces() &&
   420       !secondary_supers()->is_shared()) {
   421     MetadataFactory::free_array<Klass*>(loader_data, secondary_supers());
   422   }
   423   set_secondary_supers(NULL);
   425   deallocate_interfaces(loader_data, super(), local_interfaces(), transitive_interfaces());
   426   set_transitive_interfaces(NULL);
   427   set_local_interfaces(NULL);
   429   if (fields() != NULL && !fields()->is_shared()) {
   430     MetadataFactory::free_array<jushort>(loader_data, fields());
   431   }
   432   set_fields(NULL, 0);
   434   // If a method from a redefined class is using this constant pool, don't
   435   // delete it, yet.  The new class's previous version will point to this.
   436   if (constants() != NULL) {
   437     assert (!constants()->on_stack(), "shouldn't be called if anything is onstack");
   438     if (!constants()->is_shared()) {
   439       MetadataFactory::free_metadata(loader_data, constants());
   440     }
   441     set_constants(NULL);
   442   }
   444   if (inner_classes() != NULL &&
   445       inner_classes() != Universe::the_empty_short_array() &&
   446       !inner_classes()->is_shared()) {
   447     MetadataFactory::free_array<jushort>(loader_data, inner_classes());
   448   }
   449   set_inner_classes(NULL);
   451   // We should deallocate the Annotations instance if it's not in shared spaces.
   452   if (annotations() != NULL && !annotations()->is_shared()) {
   453     MetadataFactory::free_metadata(loader_data, annotations());
   454   }
   455   set_annotations(NULL);
   456 }
   458 bool InstanceKlass::should_be_initialized() const {
   459   return !is_initialized();
   460 }
   462 klassVtable* InstanceKlass::vtable() const {
   463   return new klassVtable(this, start_of_vtable(), vtable_length() / vtableEntry::size());
   464 }
   466 klassItable* InstanceKlass::itable() const {
   467   return new klassItable(instanceKlassHandle(this));
   468 }
   470 void InstanceKlass::eager_initialize(Thread *thread) {
   471   if (!EagerInitialization) return;
   473   if (this->is_not_initialized()) {
   474     // abort if the the class has a class initializer
   475     if (this->class_initializer() != NULL) return;
   477     // abort if it is java.lang.Object (initialization is handled in genesis)
   478     Klass* super = this->super();
   479     if (super == NULL) return;
   481     // abort if the super class should be initialized
   482     if (!InstanceKlass::cast(super)->is_initialized()) return;
   484     // call body to expose the this pointer
   485     instanceKlassHandle this_oop(thread, this);
   486     eager_initialize_impl(this_oop);
   487   }
   488 }
   490 // JVMTI spec thinks there are signers and protection domain in the
   491 // instanceKlass.  These accessors pretend these fields are there.
   492 // The hprof specification also thinks these fields are in InstanceKlass.
   493 oop InstanceKlass::protection_domain() const {
   494   // return the protection_domain from the mirror
   495   return java_lang_Class::protection_domain(java_mirror());
   496 }
   498 // To remove these from requires an incompatible change and CCC request.
   499 objArrayOop InstanceKlass::signers() const {
   500   // return the signers from the mirror
   501   return java_lang_Class::signers(java_mirror());
   502 }
   504 oop InstanceKlass::init_lock() const {
   505   // return the init lock from the mirror
   506   oop lock = java_lang_Class::init_lock(java_mirror());
   507   // Prevent reordering with any access of initialization state
   508   OrderAccess::loadload();
   509   assert((oop)lock != NULL || !is_not_initialized(), // initialized or in_error state
   510          "only fully initialized state can have a null lock");
   511   return lock;
   512 }
   514 // Set the initialization lock to null so the object can be GC'ed.  Any racing
   515 // threads to get this lock will see a null lock and will not lock.
   516 // That's okay because they all check for initialized state after getting
   517 // the lock and return.
   518 void InstanceKlass::fence_and_clear_init_lock() {
   519   // make sure previous stores are all done, notably the init_state.
   520   OrderAccess::storestore();
   521   java_lang_Class::set_init_lock(java_mirror(), NULL);
   522   assert(!is_not_initialized(), "class must be initialized now");
   523 }
   525 void InstanceKlass::eager_initialize_impl(instanceKlassHandle this_oop) {
   526   EXCEPTION_MARK;
   527   oop init_lock = this_oop->init_lock();
   528   ObjectLocker ol(init_lock, THREAD, init_lock != NULL);
   530   // abort if someone beat us to the initialization
   531   if (!this_oop->is_not_initialized()) return;  // note: not equivalent to is_initialized()
   533   ClassState old_state = this_oop->init_state();
   534   link_class_impl(this_oop, true, THREAD);
   535   if (HAS_PENDING_EXCEPTION) {
   536     CLEAR_PENDING_EXCEPTION;
   537     // Abort if linking the class throws an exception.
   539     // Use a test to avoid redundantly resetting the state if there's
   540     // no change.  Set_init_state() asserts that state changes make
   541     // progress, whereas here we might just be spinning in place.
   542     if( old_state != this_oop->_init_state )
   543       this_oop->set_init_state (old_state);
   544   } else {
   545     // linking successfull, mark class as initialized
   546     this_oop->set_init_state (fully_initialized);
   547     this_oop->fence_and_clear_init_lock();
   548     // trace
   549     if (TraceClassInitialization) {
   550       ResourceMark rm(THREAD);
   551       tty->print_cr("[Initialized %s without side effects]", this_oop->external_name());
   552     }
   553   }
   554 }
   557 // See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization
   558 // process. The step comments refers to the procedure described in that section.
   559 // Note: implementation moved to static method to expose the this pointer.
   560 void InstanceKlass::initialize(TRAPS) {
   561   if (this->should_be_initialized()) {
   562     HandleMark hm(THREAD);
   563     instanceKlassHandle this_oop(THREAD, this);
   564     initialize_impl(this_oop, CHECK);
   565     // Note: at this point the class may be initialized
   566     //       OR it may be in the state of being initialized
   567     //       in case of recursive initialization!
   568   } else {
   569     assert(is_initialized(), "sanity check");
   570   }
   571 }
   574 bool InstanceKlass::verify_code(
   575     instanceKlassHandle this_oop, bool throw_verifyerror, TRAPS) {
   576   // 1) Verify the bytecodes
   577   Verifier::Mode mode =
   578     throw_verifyerror ? Verifier::ThrowException : Verifier::NoException;
   579   return Verifier::verify(this_oop, mode, this_oop->should_verify_class(), CHECK_false);
   580 }
   583 // Used exclusively by the shared spaces dump mechanism to prevent
   584 // classes mapped into the shared regions in new VMs from appearing linked.
   586 void InstanceKlass::unlink_class() {
   587   assert(is_linked(), "must be linked");
   588   _init_state = loaded;
   589 }
   591 void InstanceKlass::link_class(TRAPS) {
   592   assert(is_loaded(), "must be loaded");
   593   if (!is_linked()) {
   594     HandleMark hm(THREAD);
   595     instanceKlassHandle this_oop(THREAD, this);
   596     link_class_impl(this_oop, true, CHECK);
   597   }
   598 }
   600 // Called to verify that a class can link during initialization, without
   601 // throwing a VerifyError.
   602 bool InstanceKlass::link_class_or_fail(TRAPS) {
   603   assert(is_loaded(), "must be loaded");
   604   if (!is_linked()) {
   605     HandleMark hm(THREAD);
   606     instanceKlassHandle this_oop(THREAD, this);
   607     link_class_impl(this_oop, false, CHECK_false);
   608   }
   609   return is_linked();
   610 }
   612 bool InstanceKlass::link_class_impl(
   613     instanceKlassHandle this_oop, bool throw_verifyerror, TRAPS) {
   614   // check for error state
   615   if (this_oop->is_in_error_state()) {
   616     ResourceMark rm(THREAD);
   617     THROW_MSG_(vmSymbols::java_lang_NoClassDefFoundError(),
   618                this_oop->external_name(), false);
   619   }
   620   // return if already verified
   621   if (this_oop->is_linked()) {
   622     return true;
   623   }
   625   // Timing
   626   // timer handles recursion
   627   assert(THREAD->is_Java_thread(), "non-JavaThread in link_class_impl");
   628   JavaThread* jt = (JavaThread*)THREAD;
   630   // link super class before linking this class
   631   instanceKlassHandle super(THREAD, this_oop->super());
   632   if (super.not_null()) {
   633     if (super->is_interface()) {  // check if super class is an interface
   634       ResourceMark rm(THREAD);
   635       Exceptions::fthrow(
   636         THREAD_AND_LOCATION,
   637         vmSymbols::java_lang_IncompatibleClassChangeError(),
   638         "class %s has interface %s as super class",
   639         this_oop->external_name(),
   640         super->external_name()
   641       );
   642       return false;
   643     }
   645     link_class_impl(super, throw_verifyerror, CHECK_false);
   646   }
   648   // link all interfaces implemented by this class before linking this class
   649   Array<Klass*>* interfaces = this_oop->local_interfaces();
   650   int num_interfaces = interfaces->length();
   651   for (int index = 0; index < num_interfaces; index++) {
   652     HandleMark hm(THREAD);
   653     instanceKlassHandle ih(THREAD, interfaces->at(index));
   654     link_class_impl(ih, throw_verifyerror, CHECK_false);
   655   }
   657   // in case the class is linked in the process of linking its superclasses
   658   if (this_oop->is_linked()) {
   659     return true;
   660   }
   662   // trace only the link time for this klass that includes
   663   // the verification time
   664   PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(),
   665                              ClassLoader::perf_class_link_selftime(),
   666                              ClassLoader::perf_classes_linked(),
   667                              jt->get_thread_stat()->perf_recursion_counts_addr(),
   668                              jt->get_thread_stat()->perf_timers_addr(),
   669                              PerfClassTraceTime::CLASS_LINK);
   671   // verification & rewriting
   672   {
   673     oop init_lock = this_oop->init_lock();
   674     ObjectLocker ol(init_lock, THREAD, init_lock != NULL);
   675     // rewritten will have been set if loader constraint error found
   676     // on an earlier link attempt
   677     // don't verify or rewrite if already rewritten
   679     if (!this_oop->is_linked()) {
   680       if (!this_oop->is_rewritten()) {
   681         {
   682           // Timer includes any side effects of class verification (resolution,
   683           // etc), but not recursive entry into verify_code().
   684           PerfClassTraceTime timer(ClassLoader::perf_class_verify_time(),
   685                                    ClassLoader::perf_class_verify_selftime(),
   686                                    ClassLoader::perf_classes_verified(),
   687                                    jt->get_thread_stat()->perf_recursion_counts_addr(),
   688                                    jt->get_thread_stat()->perf_timers_addr(),
   689                                    PerfClassTraceTime::CLASS_VERIFY);
   690           bool verify_ok = verify_code(this_oop, throw_verifyerror, THREAD);
   691           if (!verify_ok) {
   692             return false;
   693           }
   694         }
   696         // Just in case a side-effect of verify linked this class already
   697         // (which can sometimes happen since the verifier loads classes
   698         // using custom class loaders, which are free to initialize things)
   699         if (this_oop->is_linked()) {
   700           return true;
   701         }
   703         // also sets rewritten
   704         this_oop->rewrite_class(CHECK_false);
   705       }
   707       // relocate jsrs and link methods after they are all rewritten
   708       this_oop->link_methods(CHECK_false);
   710       // Initialize the vtable and interface table after
   711       // methods have been rewritten since rewrite may
   712       // fabricate new Method*s.
   713       // also does loader constraint checking
   714       if (!this_oop()->is_shared()) {
   715         ResourceMark rm(THREAD);
   716         this_oop->vtable()->initialize_vtable(true, CHECK_false);
   717         this_oop->itable()->initialize_itable(true, CHECK_false);
   718       }
   719 #ifdef ASSERT
   720       else {
   721         ResourceMark rm(THREAD);
   722         this_oop->vtable()->verify(tty, true);
   723         // In case itable verification is ever added.
   724         // this_oop->itable()->verify(tty, true);
   725       }
   726 #endif
   727       this_oop->set_init_state(linked);
   728       if (JvmtiExport::should_post_class_prepare()) {
   729         Thread *thread = THREAD;
   730         assert(thread->is_Java_thread(), "thread->is_Java_thread()");
   731         JvmtiExport::post_class_prepare((JavaThread *) thread, this_oop());
   732       }
   733     }
   734   }
   735   return true;
   736 }
   739 // Rewrite the byte codes of all of the methods of a class.
   740 // The rewriter must be called exactly once. Rewriting must happen after
   741 // verification but before the first method of the class is executed.
   742 void InstanceKlass::rewrite_class(TRAPS) {
   743   assert(is_loaded(), "must be loaded");
   744   instanceKlassHandle this_oop(THREAD, this);
   745   if (this_oop->is_rewritten()) {
   746     assert(this_oop()->is_shared(), "rewriting an unshared class?");
   747     return;
   748   }
   749   Rewriter::rewrite(this_oop, CHECK);
   750   this_oop->set_rewritten();
   751 }
   753 // Now relocate and link method entry points after class is rewritten.
   754 // This is outside is_rewritten flag. In case of an exception, it can be
   755 // executed more than once.
   756 void InstanceKlass::link_methods(TRAPS) {
   757   int len = methods()->length();
   758   for (int i = len-1; i >= 0; i--) {
   759     methodHandle m(THREAD, methods()->at(i));
   761     // Set up method entry points for compiler and interpreter    .
   762     m->link_method(m, CHECK);
   764     // This is for JVMTI and unrelated to relocator but the last thing we do
   765 #ifdef ASSERT
   766     if (StressMethodComparator) {
   767       ResourceMark rm(THREAD);
   768       static int nmc = 0;
   769       for (int j = i; j >= 0 && j >= i-4; j--) {
   770         if ((++nmc % 1000) == 0)  tty->print_cr("Have run MethodComparator %d times...", nmc);
   771         bool z = MethodComparator::methods_EMCP(m(),
   772                    methods()->at(j));
   773         if (j == i && !z) {
   774           tty->print("MethodComparator FAIL: "); m->print(); m->print_codes();
   775           assert(z, "method must compare equal to itself");
   776         }
   777       }
   778     }
   779 #endif //ASSERT
   780   }
   781 }
   783 // Eagerly initialize superinterfaces that declare default methods (concrete instance: any access)
   784 void InstanceKlass::initialize_super_interfaces(instanceKlassHandle this_oop, TRAPS) {
   785   if (this_oop->has_default_methods()) {
   786     for (int i = 0; i < this_oop->local_interfaces()->length(); ++i) {
   787       Klass* iface = this_oop->local_interfaces()->at(i);
   788       InstanceKlass* ik = InstanceKlass::cast(iface);
   789       if (ik->should_be_initialized()) {
   790         if (ik->has_default_methods()) {
   791           ik->initialize_super_interfaces(ik, THREAD);
   792         }
   793         // Only initialize() interfaces that "declare" concrete methods.
   794         // has_default_methods drives searching superinterfaces since it
   795         // means has_default_methods in its superinterface hierarchy
   796         if (!HAS_PENDING_EXCEPTION && ik->declares_default_methods()) {
   797           ik->initialize(THREAD);
   798         }
   799         if (HAS_PENDING_EXCEPTION) {
   800           Handle e(THREAD, PENDING_EXCEPTION);
   801           CLEAR_PENDING_EXCEPTION;
   802           {
   803             EXCEPTION_MARK;
   804             // Locks object, set state, and notify all waiting threads
   805             this_oop->set_initialization_state_and_notify(
   806                 initialization_error, THREAD);
   808             // ignore any exception thrown, superclass initialization error is
   809             // thrown below
   810             CLEAR_PENDING_EXCEPTION;
   811           }
   812           THROW_OOP(e());
   813         }
   814       }
   815     }
   816   }
   817 }
   819 void InstanceKlass::initialize_impl(instanceKlassHandle this_oop, TRAPS) {
   820   // Make sure klass is linked (verified) before initialization
   821   // A class could already be verified, since it has been reflected upon.
   822   this_oop->link_class(CHECK);
   824   DTRACE_CLASSINIT_PROBE(required, InstanceKlass::cast(this_oop()), -1);
   826   bool wait = false;
   828   // refer to the JVM book page 47 for description of steps
   829   // Step 1
   830   {
   831     oop init_lock = this_oop->init_lock();
   832     ObjectLocker ol(init_lock, THREAD, init_lock != NULL);
   834     Thread *self = THREAD; // it's passed the current thread
   836     // Step 2
   837     // If we were to use wait() instead of waitInterruptibly() then
   838     // we might end up throwing IE from link/symbol resolution sites
   839     // that aren't expected to throw.  This would wreak havoc.  See 6320309.
   840     while(this_oop->is_being_initialized() && !this_oop->is_reentrant_initialization(self)) {
   841         wait = true;
   842       ol.waitUninterruptibly(CHECK);
   843     }
   845     // Step 3
   846     if (this_oop->is_being_initialized() && this_oop->is_reentrant_initialization(self)) {
   847       DTRACE_CLASSINIT_PROBE_WAIT(recursive, InstanceKlass::cast(this_oop()), -1,wait);
   848       return;
   849     }
   851     // Step 4
   852     if (this_oop->is_initialized()) {
   853       DTRACE_CLASSINIT_PROBE_WAIT(concurrent, InstanceKlass::cast(this_oop()), -1,wait);
   854       return;
   855     }
   857     // Step 5
   858     if (this_oop->is_in_error_state()) {
   859       DTRACE_CLASSINIT_PROBE_WAIT(erroneous, InstanceKlass::cast(this_oop()), -1,wait);
   860       ResourceMark rm(THREAD);
   861       const char* desc = "Could not initialize class ";
   862       const char* className = this_oop->external_name();
   863       size_t msglen = strlen(desc) + strlen(className) + 1;
   864       char* message = NEW_RESOURCE_ARRAY(char, msglen);
   865       if (NULL == message) {
   866         // Out of memory: can't create detailed error message
   867         THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), className);
   868       } else {
   869         jio_snprintf(message, msglen, "%s%s", desc, className);
   870         THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), message);
   871       }
   872     }
   874     // Step 6
   875     this_oop->set_init_state(being_initialized);
   876     this_oop->set_init_thread(self);
   877   }
   879   // Step 7
   880   Klass* super_klass = this_oop->super();
   881   if (super_klass != NULL && !this_oop->is_interface() && super_klass->should_be_initialized()) {
   882     super_klass->initialize(THREAD);
   884     if (HAS_PENDING_EXCEPTION) {
   885       Handle e(THREAD, PENDING_EXCEPTION);
   886       CLEAR_PENDING_EXCEPTION;
   887       {
   888         EXCEPTION_MARK;
   889         this_oop->set_initialization_state_and_notify(initialization_error, THREAD); // Locks object, set state, and notify all waiting threads
   890         CLEAR_PENDING_EXCEPTION;   // ignore any exception thrown, superclass initialization error is thrown below
   891       }
   892       DTRACE_CLASSINIT_PROBE_WAIT(super__failed, InstanceKlass::cast(this_oop()), -1,wait);
   893       THROW_OOP(e());
   894     }
   895   }
   897   // Recursively initialize any superinterfaces that declare default methods
   898   // Only need to recurse if has_default_methods which includes declaring and
   899   // inheriting default methods
   900   if (this_oop->has_default_methods()) {
   901     this_oop->initialize_super_interfaces(this_oop, CHECK);
   902   }
   904   // Step 8
   905   {
   906     assert(THREAD->is_Java_thread(), "non-JavaThread in initialize_impl");
   907     JavaThread* jt = (JavaThread*)THREAD;
   908     DTRACE_CLASSINIT_PROBE_WAIT(clinit, InstanceKlass::cast(this_oop()), -1,wait);
   909     // Timer includes any side effects of class initialization (resolution,
   910     // etc), but not recursive entry into call_class_initializer().
   911     PerfClassTraceTime timer(ClassLoader::perf_class_init_time(),
   912                              ClassLoader::perf_class_init_selftime(),
   913                              ClassLoader::perf_classes_inited(),
   914                              jt->get_thread_stat()->perf_recursion_counts_addr(),
   915                              jt->get_thread_stat()->perf_timers_addr(),
   916                              PerfClassTraceTime::CLASS_CLINIT);
   917     this_oop->call_class_initializer(THREAD);
   918   }
   920   // Step 9
   921   if (!HAS_PENDING_EXCEPTION) {
   922     this_oop->set_initialization_state_and_notify(fully_initialized, CHECK);
   923     { ResourceMark rm(THREAD);
   924       debug_only(this_oop->vtable()->verify(tty, true);)
   925     }
   926   }
   927   else {
   928     // Step 10 and 11
   929     Handle e(THREAD, PENDING_EXCEPTION);
   930     CLEAR_PENDING_EXCEPTION;
   931     {
   932       EXCEPTION_MARK;
   933       this_oop->set_initialization_state_and_notify(initialization_error, THREAD);
   934       CLEAR_PENDING_EXCEPTION;   // ignore any exception thrown, class initialization error is thrown below
   935     }
   936     DTRACE_CLASSINIT_PROBE_WAIT(error, InstanceKlass::cast(this_oop()), -1,wait);
   937     if (e->is_a(SystemDictionary::Error_klass())) {
   938       THROW_OOP(e());
   939     } else {
   940       JavaCallArguments args(e);
   941       THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(),
   942                 vmSymbols::throwable_void_signature(),
   943                 &args);
   944     }
   945   }
   946   DTRACE_CLASSINIT_PROBE_WAIT(end, InstanceKlass::cast(this_oop()), -1,wait);
   947 }
   950 // Note: implementation moved to static method to expose the this pointer.
   951 void InstanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) {
   952   instanceKlassHandle kh(THREAD, this);
   953   set_initialization_state_and_notify_impl(kh, state, CHECK);
   954 }
   956 void InstanceKlass::set_initialization_state_and_notify_impl(instanceKlassHandle this_oop, ClassState state, TRAPS) {
   957   oop init_lock = this_oop->init_lock();
   958   ObjectLocker ol(init_lock, THREAD, init_lock != NULL);
   959   this_oop->set_init_state(state);
   960   this_oop->fence_and_clear_init_lock();
   961   ol.notify_all(CHECK);
   962 }
   964 // The embedded _implementor field can only record one implementor.
   965 // When there are more than one implementors, the _implementor field
   966 // is set to the interface Klass* itself. Following are the possible
   967 // values for the _implementor field:
   968 //   NULL                  - no implementor
   969 //   implementor Klass*    - one implementor
   970 //   self                  - more than one implementor
   971 //
   972 // The _implementor field only exists for interfaces.
   973 void InstanceKlass::add_implementor(Klass* k) {
   974   assert(Compile_lock->owned_by_self(), "");
   975   assert(is_interface(), "not interface");
   976   // Filter out my subinterfaces.
   977   // (Note: Interfaces are never on the subklass list.)
   978   if (InstanceKlass::cast(k)->is_interface()) return;
   980   // Filter out subclasses whose supers already implement me.
   981   // (Note: CHA must walk subclasses of direct implementors
   982   // in order to locate indirect implementors.)
   983   Klass* sk = InstanceKlass::cast(k)->super();
   984   if (sk != NULL && InstanceKlass::cast(sk)->implements_interface(this))
   985     // We only need to check one immediate superclass, since the
   986     // implements_interface query looks at transitive_interfaces.
   987     // Any supers of the super have the same (or fewer) transitive_interfaces.
   988     return;
   990   Klass* ik = implementor();
   991   if (ik == NULL) {
   992     set_implementor(k);
   993   } else if (ik != this) {
   994     // There is already an implementor. Use itself as an indicator of
   995     // more than one implementors.
   996     set_implementor(this);
   997   }
   999   // The implementor also implements the transitive_interfaces
  1000   for (int index = 0; index < local_interfaces()->length(); index++) {
  1001     InstanceKlass::cast(local_interfaces()->at(index))->add_implementor(k);
  1005 void InstanceKlass::init_implementor() {
  1006   if (is_interface()) {
  1007     set_implementor(NULL);
  1012 void InstanceKlass::process_interfaces(Thread *thread) {
  1013   // link this class into the implementors list of every interface it implements
  1014   Klass* this_as_klass_oop = this;
  1015   for (int i = local_interfaces()->length() - 1; i >= 0; i--) {
  1016     assert(local_interfaces()->at(i)->is_klass(), "must be a klass");
  1017     InstanceKlass* interf = InstanceKlass::cast(local_interfaces()->at(i));
  1018     assert(interf->is_interface(), "expected interface");
  1019     interf->add_implementor(this_as_klass_oop);
  1023 bool InstanceKlass::can_be_primary_super_slow() const {
  1024   if (is_interface())
  1025     return false;
  1026   else
  1027     return Klass::can_be_primary_super_slow();
  1030 GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots) {
  1031   // The secondaries are the implemented interfaces.
  1032   InstanceKlass* ik = InstanceKlass::cast(this);
  1033   Array<Klass*>* interfaces = ik->transitive_interfaces();
  1034   int num_secondaries = num_extra_slots + interfaces->length();
  1035   if (num_secondaries == 0) {
  1036     // Must share this for correct bootstrapping!
  1037     set_secondary_supers(Universe::the_empty_klass_array());
  1038     return NULL;
  1039   } else if (num_extra_slots == 0) {
  1040     // The secondary super list is exactly the same as the transitive interfaces.
  1041     // Redefine classes has to be careful not to delete this!
  1042     set_secondary_supers(interfaces);
  1043     return NULL;
  1044   } else {
  1045     // Copy transitive interfaces to a temporary growable array to be constructed
  1046     // into the secondary super list with extra slots.
  1047     GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length());
  1048     for (int i = 0; i < interfaces->length(); i++) {
  1049       secondaries->push(interfaces->at(i));
  1051     return secondaries;
  1055 bool InstanceKlass::compute_is_subtype_of(Klass* k) {
  1056   if (k->is_interface()) {
  1057     return implements_interface(k);
  1058   } else {
  1059     return Klass::compute_is_subtype_of(k);
  1063 bool InstanceKlass::implements_interface(Klass* k) const {
  1064   if (this == k) return true;
  1065   assert(k->is_interface(), "should be an interface class");
  1066   for (int i = 0; i < transitive_interfaces()->length(); i++) {
  1067     if (transitive_interfaces()->at(i) == k) {
  1068       return true;
  1071   return false;
  1074 bool InstanceKlass::is_same_or_direct_interface(Klass *k) const {
  1075   // Verify direct super interface
  1076   if (this == k) return true;
  1077   assert(k->is_interface(), "should be an interface class");
  1078   for (int i = 0; i < local_interfaces()->length(); i++) {
  1079     if (local_interfaces()->at(i) == k) {
  1080       return true;
  1083   return false;
  1086 objArrayOop InstanceKlass::allocate_objArray(int n, int length, TRAPS) {
  1087   if (length < 0) THROW_0(vmSymbols::java_lang_NegativeArraySizeException());
  1088   if (length > arrayOopDesc::max_array_length(T_OBJECT)) {
  1089     report_java_out_of_memory("Requested array size exceeds VM limit");
  1090     JvmtiExport::post_array_size_exhausted();
  1091     THROW_OOP_0(Universe::out_of_memory_error_array_size());
  1093   int size = objArrayOopDesc::object_size(length);
  1094   Klass* ak = array_klass(n, CHECK_NULL);
  1095   KlassHandle h_ak (THREAD, ak);
  1096   objArrayOop o =
  1097     (objArrayOop)CollectedHeap::array_allocate(h_ak, size, length, CHECK_NULL);
  1098   return o;
  1101 instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) {
  1102   if (TraceFinalizerRegistration) {
  1103     tty->print("Registered ");
  1104     i->print_value_on(tty);
  1105     tty->print_cr(" (" INTPTR_FORMAT ") as finalizable", (address)i);
  1107   instanceHandle h_i(THREAD, i);
  1108   // Pass the handle as argument, JavaCalls::call expects oop as jobjects
  1109   JavaValue result(T_VOID);
  1110   JavaCallArguments args(h_i);
  1111   methodHandle mh (THREAD, Universe::finalizer_register_method());
  1112   JavaCalls::call(&result, mh, &args, CHECK_NULL);
  1113   return h_i();
  1116 instanceOop InstanceKlass::allocate_instance(TRAPS) {
  1117   bool has_finalizer_flag = has_finalizer(); // Query before possible GC
  1118   int size = size_helper();  // Query before forming handle.
  1120   KlassHandle h_k(THREAD, this);
  1122   instanceOop i;
  1124   i = (instanceOop)CollectedHeap::obj_allocate(h_k, size, CHECK_NULL);
  1125   if (has_finalizer_flag && !RegisterFinalizersAtInit) {
  1126     i = register_finalizer(i, CHECK_NULL);
  1128   return i;
  1131 void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) {
  1132   if (is_interface() || is_abstract()) {
  1133     ResourceMark rm(THREAD);
  1134     THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
  1135               : vmSymbols::java_lang_InstantiationException(), external_name());
  1137   if (this == SystemDictionary::Class_klass()) {
  1138     ResourceMark rm(THREAD);
  1139     THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError()
  1140               : vmSymbols::java_lang_IllegalAccessException(), external_name());
  1144 Klass* InstanceKlass::array_klass_impl(bool or_null, int n, TRAPS) {
  1145   instanceKlassHandle this_oop(THREAD, this);
  1146   return array_klass_impl(this_oop, or_null, n, THREAD);
  1149 Klass* InstanceKlass::array_klass_impl(instanceKlassHandle this_oop, bool or_null, int n, TRAPS) {
  1150   if (this_oop->array_klasses() == NULL) {
  1151     if (or_null) return NULL;
  1153     ResourceMark rm;
  1154     JavaThread *jt = (JavaThread *)THREAD;
  1156       // Atomic creation of array_klasses
  1157       MutexLocker mc(Compile_lock, THREAD);   // for vtables
  1158       MutexLocker ma(MultiArray_lock, THREAD);
  1160       // Check if update has already taken place
  1161       if (this_oop->array_klasses() == NULL) {
  1162         Klass*    k = ObjArrayKlass::allocate_objArray_klass(this_oop->class_loader_data(), 1, this_oop, CHECK_NULL);
  1163         this_oop->set_array_klasses(k);
  1167   // _this will always be set at this point
  1168   ObjArrayKlass* oak = (ObjArrayKlass*)this_oop->array_klasses();
  1169   if (or_null) {
  1170     return oak->array_klass_or_null(n);
  1172   return oak->array_klass(n, CHECK_NULL);
  1175 Klass* InstanceKlass::array_klass_impl(bool or_null, TRAPS) {
  1176   return array_klass_impl(or_null, 1, THREAD);
  1179 void InstanceKlass::call_class_initializer(TRAPS) {
  1180   instanceKlassHandle ik (THREAD, this);
  1181   call_class_initializer_impl(ik, THREAD);
  1184 static int call_class_initializer_impl_counter = 0;   // for debugging
  1186 Method* InstanceKlass::class_initializer() {
  1187   Method* clinit = find_method(
  1188       vmSymbols::class_initializer_name(), vmSymbols::void_method_signature());
  1189   if (clinit != NULL && clinit->has_valid_initializer_flags()) {
  1190     return clinit;
  1192   return NULL;
  1195 void InstanceKlass::call_class_initializer_impl(instanceKlassHandle this_oop, TRAPS) {
  1196   if (ReplayCompiles &&
  1197       (ReplaySuppressInitializers == 1 ||
  1198        ReplaySuppressInitializers >= 2 && this_oop->class_loader() != NULL)) {
  1199     // Hide the existence of the initializer for the purpose of replaying the compile
  1200     return;
  1203   methodHandle h_method(THREAD, this_oop->class_initializer());
  1204   assert(!this_oop->is_initialized(), "we cannot initialize twice");
  1205   if (TraceClassInitialization) {
  1206     tty->print("%d Initializing ", call_class_initializer_impl_counter++);
  1207     this_oop->name()->print_value();
  1208     tty->print_cr("%s (" INTPTR_FORMAT ")", h_method() == NULL ? "(no method)" : "", (address)this_oop());
  1210   if (h_method() != NULL) {
  1211     JavaCallArguments args; // No arguments
  1212     JavaValue result(T_VOID);
  1213     JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args)
  1218 void InstanceKlass::mask_for(methodHandle method, int bci,
  1219   InterpreterOopMap* entry_for) {
  1220   // Dirty read, then double-check under a lock.
  1221   if (_oop_map_cache == NULL) {
  1222     // Otherwise, allocate a new one.
  1223     MutexLocker x(OopMapCacheAlloc_lock);
  1224     // First time use. Allocate a cache in C heap
  1225     if (_oop_map_cache == NULL) {
  1226       // Release stores from OopMapCache constructor before assignment
  1227       // to _oop_map_cache. C++ compilers on ppc do not emit the
  1228       // required memory barrier only because of the volatile
  1229       // qualifier of _oop_map_cache.
  1230       OrderAccess::release_store_ptr(&_oop_map_cache, new OopMapCache());
  1233   // _oop_map_cache is constant after init; lookup below does is own locking.
  1234   _oop_map_cache->lookup(method, bci, entry_for);
  1238 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
  1239   for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
  1240     Symbol* f_name = fs.name();
  1241     Symbol* f_sig  = fs.signature();
  1242     if (f_name == name && f_sig == sig) {
  1243       fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
  1244       return true;
  1247   return false;
  1251 Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
  1252   const int n = local_interfaces()->length();
  1253   for (int i = 0; i < n; i++) {
  1254     Klass* intf1 = local_interfaces()->at(i);
  1255     assert(intf1->is_interface(), "just checking type");
  1256     // search for field in current interface
  1257     if (InstanceKlass::cast(intf1)->find_local_field(name, sig, fd)) {
  1258       assert(fd->is_static(), "interface field must be static");
  1259       return intf1;
  1261     // search for field in direct superinterfaces
  1262     Klass* intf2 = InstanceKlass::cast(intf1)->find_interface_field(name, sig, fd);
  1263     if (intf2 != NULL) return intf2;
  1265   // otherwise field lookup fails
  1266   return NULL;
  1270 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
  1271   // search order according to newest JVM spec (5.4.3.2, p.167).
  1272   // 1) search for field in current klass
  1273   if (find_local_field(name, sig, fd)) {
  1274     return const_cast<InstanceKlass*>(this);
  1276   // 2) search for field recursively in direct superinterfaces
  1277   { Klass* intf = find_interface_field(name, sig, fd);
  1278     if (intf != NULL) return intf;
  1280   // 3) apply field lookup recursively if superclass exists
  1281   { Klass* supr = super();
  1282     if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, fd);
  1284   // 4) otherwise field lookup fails
  1285   return NULL;
  1289 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const {
  1290   // search order according to newest JVM spec (5.4.3.2, p.167).
  1291   // 1) search for field in current klass
  1292   if (find_local_field(name, sig, fd)) {
  1293     if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this);
  1295   // 2) search for field recursively in direct superinterfaces
  1296   if (is_static) {
  1297     Klass* intf = find_interface_field(name, sig, fd);
  1298     if (intf != NULL) return intf;
  1300   // 3) apply field lookup recursively if superclass exists
  1301   { Klass* supr = super();
  1302     if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, is_static, fd);
  1304   // 4) otherwise field lookup fails
  1305   return NULL;
  1309 bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
  1310   for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
  1311     if (fs.offset() == offset) {
  1312       fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
  1313       if (fd->is_static() == is_static) return true;
  1316   return false;
  1320 bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
  1321   Klass* klass = const_cast<InstanceKlass*>(this);
  1322   while (klass != NULL) {
  1323     if (InstanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) {
  1324       return true;
  1326     klass = klass->super();
  1328   return false;
  1332 void InstanceKlass::methods_do(void f(Method* method)) {
  1333   int len = methods()->length();
  1334   for (int index = 0; index < len; index++) {
  1335     Method* m = methods()->at(index);
  1336     assert(m->is_method(), "must be method");
  1337     f(m);
  1342 void InstanceKlass::do_local_static_fields(FieldClosure* cl) {
  1343   for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
  1344     if (fs.access_flags().is_static()) {
  1345       fieldDescriptor& fd = fs.field_descriptor();
  1346       cl->do_field(&fd);
  1352 void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle mirror, TRAPS) {
  1353   instanceKlassHandle h_this(THREAD, this);
  1354   do_local_static_fields_impl(h_this, f, mirror, CHECK);
  1358 void InstanceKlass::do_local_static_fields_impl(instanceKlassHandle this_k,
  1359                              void f(fieldDescriptor* fd, Handle mirror, TRAPS), Handle mirror, TRAPS) {
  1360   for (JavaFieldStream fs(this_k()); !fs.done(); fs.next()) {
  1361     if (fs.access_flags().is_static()) {
  1362       fieldDescriptor& fd = fs.field_descriptor();
  1363       f(&fd, mirror, CHECK);
  1369 static int compare_fields_by_offset(int* a, int* b) {
  1370   return a[0] - b[0];
  1373 void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) {
  1374   InstanceKlass* super = superklass();
  1375   if (super != NULL) {
  1376     super->do_nonstatic_fields(cl);
  1378   fieldDescriptor fd;
  1379   int length = java_fields_count();
  1380   // In DebugInfo nonstatic fields are sorted by offset.
  1381   int* fields_sorted = NEW_C_HEAP_ARRAY(int, 2*(length+1), mtClass);
  1382   int j = 0;
  1383   for (int i = 0; i < length; i += 1) {
  1384     fd.reinitialize(this, i);
  1385     if (!fd.is_static()) {
  1386       fields_sorted[j + 0] = fd.offset();
  1387       fields_sorted[j + 1] = i;
  1388       j += 2;
  1391   if (j > 0) {
  1392     length = j;
  1393     // _sort_Fn is defined in growableArray.hpp.
  1394     qsort(fields_sorted, length/2, 2*sizeof(int), (_sort_Fn)compare_fields_by_offset);
  1395     for (int i = 0; i < length; i += 2) {
  1396       fd.reinitialize(this, fields_sorted[i + 1]);
  1397       assert(!fd.is_static() && fd.offset() == fields_sorted[i], "only nonstatic fields");
  1398       cl->do_field(&fd);
  1401   FREE_C_HEAP_ARRAY(int, fields_sorted, mtClass);
  1405 void InstanceKlass::array_klasses_do(void f(Klass* k, TRAPS), TRAPS) {
  1406   if (array_klasses() != NULL)
  1407     ArrayKlass::cast(array_klasses())->array_klasses_do(f, THREAD);
  1410 void InstanceKlass::array_klasses_do(void f(Klass* k)) {
  1411   if (array_klasses() != NULL)
  1412     ArrayKlass::cast(array_klasses())->array_klasses_do(f);
  1415 #ifdef ASSERT
  1416 static int linear_search(Array<Method*>* methods, Symbol* name, Symbol* signature) {
  1417   int len = methods->length();
  1418   for (int index = 0; index < len; index++) {
  1419     Method* m = methods->at(index);
  1420     assert(m->is_method(), "must be method");
  1421     if (m->signature() == signature && m->name() == name) {
  1422        return index;
  1425   return -1;
  1427 #endif
  1429 static int binary_search(Array<Method*>* methods, Symbol* name) {
  1430   int len = methods->length();
  1431   // methods are sorted, so do binary search
  1432   int l = 0;
  1433   int h = len - 1;
  1434   while (l <= h) {
  1435     int mid = (l + h) >> 1;
  1436     Method* m = methods->at(mid);
  1437     assert(m->is_method(), "must be method");
  1438     int res = m->name()->fast_compare(name);
  1439     if (res == 0) {
  1440       return mid;
  1441     } else if (res < 0) {
  1442       l = mid + 1;
  1443     } else {
  1444       h = mid - 1;
  1447   return -1;
  1450 // find_method looks up the name/signature in the local methods array
  1451 Method* InstanceKlass::find_method(Symbol* name, Symbol* signature) const {
  1452   return find_method_impl(name, signature, false);
  1455 Method* InstanceKlass::find_method_impl(Symbol* name, Symbol* signature, bool skipping_overpass) const {
  1456   return InstanceKlass::find_method_impl(methods(), name, signature, skipping_overpass);
  1459 // find_instance_method looks up the name/signature in the local methods array
  1460 // and skips over static methods
  1461 Method* InstanceKlass::find_instance_method(
  1462     Array<Method*>* methods, Symbol* name, Symbol* signature) {
  1463   Method* meth = InstanceKlass::find_method(methods, name, signature);
  1464   if (meth != NULL && meth->is_static()) {
  1465       meth = NULL;
  1467   return meth;
  1470 // find_method looks up the name/signature in the local methods array
  1471 Method* InstanceKlass::find_method(
  1472     Array<Method*>* methods, Symbol* name, Symbol* signature) {
  1473   return InstanceKlass::find_method_impl(methods, name, signature, false);
  1476 Method* InstanceKlass::find_method_impl(
  1477     Array<Method*>* methods, Symbol* name, Symbol* signature, bool skipping_overpass) {
  1478   int hit = find_method_index(methods, name, signature, skipping_overpass);
  1479   return hit >= 0 ? methods->at(hit): NULL;
  1482 // Used directly for default_methods to find the index into the
  1483 // default_vtable_indices, and indirectly by find_method
  1484 // find_method_index looks in the local methods array to return the index
  1485 // of the matching name/signature. If, overpass methods are being ignored,
  1486 // the search continues to find a potential non-overpass match.  This capability
  1487 // is important during method resolution to prefer a static method, for example,
  1488 // over an overpass method.
  1489 int InstanceKlass::find_method_index(
  1490     Array<Method*>* methods, Symbol* name, Symbol* signature, bool skipping_overpass) {
  1491   int hit = binary_search(methods, name);
  1492   if (hit != -1) {
  1493     Method* m = methods->at(hit);
  1494     // Do linear search to find matching signature.  First, quick check
  1495     // for common case, ignoring overpasses if requested.
  1496     if ((m->signature() == signature) && (!skipping_overpass || !m->is_overpass())) return hit;
  1498     // search downwards through overloaded methods
  1499     int i;
  1500     for (i = hit - 1; i >= 0; --i) {
  1501         Method* m = methods->at(i);
  1502         assert(m->is_method(), "must be method");
  1503         if (m->name() != name) break;
  1504         if ((m->signature() == signature) && (!skipping_overpass || !m->is_overpass())) return i;
  1506     // search upwards
  1507     for (i = hit + 1; i < methods->length(); ++i) {
  1508         Method* m = methods->at(i);
  1509         assert(m->is_method(), "must be method");
  1510         if (m->name() != name) break;
  1511         if ((m->signature() == signature) && (!skipping_overpass || !m->is_overpass())) return i;
  1513     // not found
  1514 #ifdef ASSERT
  1515     int index = skipping_overpass ? -1 : linear_search(methods, name, signature);
  1516     assert(index == -1, err_msg("binary search should have found entry %d", index));
  1517 #endif
  1519   return -1;
  1521 int InstanceKlass::find_method_by_name(Symbol* name, int* end) {
  1522   return find_method_by_name(methods(), name, end);
  1525 int InstanceKlass::find_method_by_name(
  1526     Array<Method*>* methods, Symbol* name, int* end_ptr) {
  1527   assert(end_ptr != NULL, "just checking");
  1528   int start = binary_search(methods, name);
  1529   int end = start + 1;
  1530   if (start != -1) {
  1531     while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start;
  1532     while (end < methods->length() && (methods->at(end))->name() == name) ++end;
  1533     *end_ptr = end;
  1534     return start;
  1536   return -1;
  1539 // uncached_lookup_method searches both the local class methods array and all
  1540 // superclasses methods arrays, skipping any overpass methods in superclasses.
  1541 Method* InstanceKlass::uncached_lookup_method(Symbol* name, Symbol* signature, MethodLookupMode mode) const {
  1542   MethodLookupMode lookup_mode = mode;
  1543   Klass* klass = const_cast<InstanceKlass*>(this);
  1544   while (klass != NULL) {
  1545     Method* method = InstanceKlass::cast(klass)->find_method_impl(name, signature, (lookup_mode == skip_overpass));
  1546     if (method != NULL) {
  1547       return method;
  1549     klass = InstanceKlass::cast(klass)->super();
  1550     lookup_mode = skip_overpass;   // Always ignore overpass methods in superclasses
  1552   return NULL;
  1555 // lookup a method in the default methods list then in all transitive interfaces
  1556 // Do NOT return private or static methods
  1557 Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name,
  1558                                                          Symbol* signature) const {
  1559   Method* m = NULL;
  1560   if (default_methods() != NULL) {
  1561     m = find_method(default_methods(), name, signature);
  1563   // Look up interfaces
  1564   if (m == NULL) {
  1565     m = lookup_method_in_all_interfaces(name, signature, normal);
  1567   return m;
  1570 // lookup a method in all the interfaces that this class implements
  1571 // Do NOT return private or static methods, new in JDK8 which are not externally visible
  1572 // They should only be found in the initial InterfaceMethodRef
  1573 Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name,
  1574                                                        Symbol* signature,
  1575                                                        MethodLookupMode mode) const {
  1576   Array<Klass*>* all_ifs = transitive_interfaces();
  1577   int num_ifs = all_ifs->length();
  1578   InstanceKlass *ik = NULL;
  1579   for (int i = 0; i < num_ifs; i++) {
  1580     ik = InstanceKlass::cast(all_ifs->at(i));
  1581     Method* m = ik->lookup_method(name, signature);
  1582     if (m != NULL && m->is_public() && !m->is_static() &&
  1583         ((mode != skip_defaults) || !m->is_default_method())) {
  1584       return m;
  1587   return NULL;
  1590 /* jni_id_for_impl for jfieldIds only */
  1591 JNIid* InstanceKlass::jni_id_for_impl(instanceKlassHandle this_oop, int offset) {
  1592   MutexLocker ml(JfieldIdCreation_lock);
  1593   // Retry lookup after we got the lock
  1594   JNIid* probe = this_oop->jni_ids() == NULL ? NULL : this_oop->jni_ids()->find(offset);
  1595   if (probe == NULL) {
  1596     // Slow case, allocate new static field identifier
  1597     probe = new JNIid(this_oop(), offset, this_oop->jni_ids());
  1598     this_oop->set_jni_ids(probe);
  1600   return probe;
  1604 /* jni_id_for for jfieldIds only */
  1605 JNIid* InstanceKlass::jni_id_for(int offset) {
  1606   JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset);
  1607   if (probe == NULL) {
  1608     probe = jni_id_for_impl(this, offset);
  1610   return probe;
  1613 u2 InstanceKlass::enclosing_method_data(int offset) {
  1614   Array<jushort>* inner_class_list = inner_classes();
  1615   if (inner_class_list == NULL) {
  1616     return 0;
  1618   int length = inner_class_list->length();
  1619   if (length % inner_class_next_offset == 0) {
  1620     return 0;
  1621   } else {
  1622     int index = length - enclosing_method_attribute_size;
  1623     assert(offset < enclosing_method_attribute_size, "invalid offset");
  1624     return inner_class_list->at(index + offset);
  1628 void InstanceKlass::set_enclosing_method_indices(u2 class_index,
  1629                                                  u2 method_index) {
  1630   Array<jushort>* inner_class_list = inner_classes();
  1631   assert (inner_class_list != NULL, "_inner_classes list is not set up");
  1632   int length = inner_class_list->length();
  1633   if (length % inner_class_next_offset == enclosing_method_attribute_size) {
  1634     int index = length - enclosing_method_attribute_size;
  1635     inner_class_list->at_put(
  1636       index + enclosing_method_class_index_offset, class_index);
  1637     inner_class_list->at_put(
  1638       index + enclosing_method_method_index_offset, method_index);
  1642 // Lookup or create a jmethodID.
  1643 // This code is called by the VMThread and JavaThreads so the
  1644 // locking has to be done very carefully to avoid deadlocks
  1645 // and/or other cache consistency problems.
  1646 //
  1647 jmethodID InstanceKlass::get_jmethod_id(instanceKlassHandle ik_h, methodHandle method_h) {
  1648   size_t idnum = (size_t)method_h->method_idnum();
  1649   jmethodID* jmeths = ik_h->methods_jmethod_ids_acquire();
  1650   size_t length = 0;
  1651   jmethodID id = NULL;
  1653   // We use a double-check locking idiom here because this cache is
  1654   // performance sensitive. In the normal system, this cache only
  1655   // transitions from NULL to non-NULL which is safe because we use
  1656   // release_set_methods_jmethod_ids() to advertise the new cache.
  1657   // A partially constructed cache should never be seen by a racing
  1658   // thread. We also use release_store_ptr() to save a new jmethodID
  1659   // in the cache so a partially constructed jmethodID should never be
  1660   // seen either. Cache reads of existing jmethodIDs proceed without a
  1661   // lock, but cache writes of a new jmethodID requires uniqueness and
  1662   // creation of the cache itself requires no leaks so a lock is
  1663   // generally acquired in those two cases.
  1664   //
  1665   // If the RedefineClasses() API has been used, then this cache can
  1666   // grow and we'll have transitions from non-NULL to bigger non-NULL.
  1667   // Cache creation requires no leaks and we require safety between all
  1668   // cache accesses and freeing of the old cache so a lock is generally
  1669   // acquired when the RedefineClasses() API has been used.
  1671   if (jmeths != NULL) {
  1672     // the cache already exists
  1673     if (!ik_h->idnum_can_increment()) {
  1674       // the cache can't grow so we can just get the current values
  1675       get_jmethod_id_length_value(jmeths, idnum, &length, &id);
  1676     } else {
  1677       // cache can grow so we have to be more careful
  1678       if (Threads::number_of_threads() == 0 ||
  1679           SafepointSynchronize::is_at_safepoint()) {
  1680         // we're single threaded or at a safepoint - no locking needed
  1681         get_jmethod_id_length_value(jmeths, idnum, &length, &id);
  1682       } else {
  1683         MutexLocker ml(JmethodIdCreation_lock);
  1684         get_jmethod_id_length_value(jmeths, idnum, &length, &id);
  1688   // implied else:
  1689   // we need to allocate a cache so default length and id values are good
  1691   if (jmeths == NULL ||   // no cache yet
  1692       length <= idnum ||  // cache is too short
  1693       id == NULL) {       // cache doesn't contain entry
  1695     // This function can be called by the VMThread so we have to do all
  1696     // things that might block on a safepoint before grabbing the lock.
  1697     // Otherwise, we can deadlock with the VMThread or have a cache
  1698     // consistency issue. These vars keep track of what we might have
  1699     // to free after the lock is dropped.
  1700     jmethodID  to_dealloc_id     = NULL;
  1701     jmethodID* to_dealloc_jmeths = NULL;
  1703     // may not allocate new_jmeths or use it if we allocate it
  1704     jmethodID* new_jmeths = NULL;
  1705     if (length <= idnum) {
  1706       // allocate a new cache that might be used
  1707       size_t size = MAX2(idnum+1, (size_t)ik_h->idnum_allocated_count());
  1708       new_jmeths = NEW_C_HEAP_ARRAY(jmethodID, size+1, mtClass);
  1709       memset(new_jmeths, 0, (size+1)*sizeof(jmethodID));
  1710       // cache size is stored in element[0], other elements offset by one
  1711       new_jmeths[0] = (jmethodID)size;
  1714     // allocate a new jmethodID that might be used
  1715     jmethodID new_id = NULL;
  1716     if (method_h->is_old() && !method_h->is_obsolete()) {
  1717       // The method passed in is old (but not obsolete), we need to use the current version
  1718       Method* current_method = ik_h->method_with_idnum((int)idnum);
  1719       assert(current_method != NULL, "old and but not obsolete, so should exist");
  1720       new_id = Method::make_jmethod_id(ik_h->class_loader_data(), current_method);
  1721     } else {
  1722       // It is the current version of the method or an obsolete method,
  1723       // use the version passed in
  1724       new_id = Method::make_jmethod_id(ik_h->class_loader_data(), method_h());
  1727     if (Threads::number_of_threads() == 0 ||
  1728         SafepointSynchronize::is_at_safepoint()) {
  1729       // we're single threaded or at a safepoint - no locking needed
  1730       id = get_jmethod_id_fetch_or_update(ik_h, idnum, new_id, new_jmeths,
  1731                                           &to_dealloc_id, &to_dealloc_jmeths);
  1732     } else {
  1733       MutexLocker ml(JmethodIdCreation_lock);
  1734       id = get_jmethod_id_fetch_or_update(ik_h, idnum, new_id, new_jmeths,
  1735                                           &to_dealloc_id, &to_dealloc_jmeths);
  1738     // The lock has been dropped so we can free resources.
  1739     // Free up either the old cache or the new cache if we allocated one.
  1740     if (to_dealloc_jmeths != NULL) {
  1741       FreeHeap(to_dealloc_jmeths);
  1743     // free up the new ID since it wasn't needed
  1744     if (to_dealloc_id != NULL) {
  1745       Method::destroy_jmethod_id(ik_h->class_loader_data(), to_dealloc_id);
  1748   return id;
  1752 // Common code to fetch the jmethodID from the cache or update the
  1753 // cache with the new jmethodID. This function should never do anything
  1754 // that causes the caller to go to a safepoint or we can deadlock with
  1755 // the VMThread or have cache consistency issues.
  1756 //
  1757 jmethodID InstanceKlass::get_jmethod_id_fetch_or_update(
  1758             instanceKlassHandle ik_h, size_t idnum, jmethodID new_id,
  1759             jmethodID* new_jmeths, jmethodID* to_dealloc_id_p,
  1760             jmethodID** to_dealloc_jmeths_p) {
  1761   assert(new_id != NULL, "sanity check");
  1762   assert(to_dealloc_id_p != NULL, "sanity check");
  1763   assert(to_dealloc_jmeths_p != NULL, "sanity check");
  1764   assert(Threads::number_of_threads() == 0 ||
  1765          SafepointSynchronize::is_at_safepoint() ||
  1766          JmethodIdCreation_lock->owned_by_self(), "sanity check");
  1768   // reacquire the cache - we are locked, single threaded or at a safepoint
  1769   jmethodID* jmeths = ik_h->methods_jmethod_ids_acquire();
  1770   jmethodID  id     = NULL;
  1771   size_t     length = 0;
  1773   if (jmeths == NULL ||                         // no cache yet
  1774       (length = (size_t)jmeths[0]) <= idnum) {  // cache is too short
  1775     if (jmeths != NULL) {
  1776       // copy any existing entries from the old cache
  1777       for (size_t index = 0; index < length; index++) {
  1778         new_jmeths[index+1] = jmeths[index+1];
  1780       *to_dealloc_jmeths_p = jmeths;  // save old cache for later delete
  1782     ik_h->release_set_methods_jmethod_ids(jmeths = new_jmeths);
  1783   } else {
  1784     // fetch jmethodID (if any) from the existing cache
  1785     id = jmeths[idnum+1];
  1786     *to_dealloc_jmeths_p = new_jmeths;  // save new cache for later delete
  1788   if (id == NULL) {
  1789     // No matching jmethodID in the existing cache or we have a new
  1790     // cache or we just grew the cache. This cache write is done here
  1791     // by the first thread to win the foot race because a jmethodID
  1792     // needs to be unique once it is generally available.
  1793     id = new_id;
  1795     // The jmethodID cache can be read while unlocked so we have to
  1796     // make sure the new jmethodID is complete before installing it
  1797     // in the cache.
  1798     OrderAccess::release_store_ptr(&jmeths[idnum+1], id);
  1799   } else {
  1800     *to_dealloc_id_p = new_id; // save new id for later delete
  1802   return id;
  1806 // Common code to get the jmethodID cache length and the jmethodID
  1807 // value at index idnum if there is one.
  1808 //
  1809 void InstanceKlass::get_jmethod_id_length_value(jmethodID* cache,
  1810        size_t idnum, size_t *length_p, jmethodID* id_p) {
  1811   assert(cache != NULL, "sanity check");
  1812   assert(length_p != NULL, "sanity check");
  1813   assert(id_p != NULL, "sanity check");
  1815   // cache size is stored in element[0], other elements offset by one
  1816   *length_p = (size_t)cache[0];
  1817   if (*length_p <= idnum) {  // cache is too short
  1818     *id_p = NULL;
  1819   } else {
  1820     *id_p = cache[idnum+1];  // fetch jmethodID (if any)
  1825 // Lookup a jmethodID, NULL if not found.  Do no blocking, no allocations, no handles
  1826 jmethodID InstanceKlass::jmethod_id_or_null(Method* method) {
  1827   size_t idnum = (size_t)method->method_idnum();
  1828   jmethodID* jmeths = methods_jmethod_ids_acquire();
  1829   size_t length;                                // length assigned as debugging crumb
  1830   jmethodID id = NULL;
  1831   if (jmeths != NULL &&                         // If there is a cache
  1832       (length = (size_t)jmeths[0]) > idnum) {   // and if it is long enough,
  1833     id = jmeths[idnum+1];                       // Look up the id (may be NULL)
  1835   return id;
  1838 int nmethodBucket::decrement() {
  1839   return Atomic::add(-1, (volatile int *)&_count);
  1842 //
  1843 // Walk the list of dependent nmethods searching for nmethods which
  1844 // are dependent on the changes that were passed in and mark them for
  1845 // deoptimization.  Returns the number of nmethods found.
  1846 //
  1847 int InstanceKlass::mark_dependent_nmethods(DepChange& changes) {
  1848   assert_locked_or_safepoint(CodeCache_lock);
  1849   int found = 0;
  1850   nmethodBucket* b = _dependencies;
  1851   while (b != NULL) {
  1852     nmethod* nm = b->get_nmethod();
  1853     // since dependencies aren't removed until an nmethod becomes a zombie,
  1854     // the dependency list may contain nmethods which aren't alive.
  1855     if (b->count() > 0 && nm->is_alive() && !nm->is_marked_for_deoptimization() && nm->check_dependency_on(changes)) {
  1856       if (TraceDependencies) {
  1857         ResourceMark rm;
  1858         tty->print_cr("Marked for deoptimization");
  1859         tty->print_cr("  context = %s", this->external_name());
  1860         changes.print();
  1861         nm->print();
  1862         nm->print_dependencies();
  1864       nm->mark_for_deoptimization();
  1865       found++;
  1867     b = b->next();
  1869   return found;
  1872 void InstanceKlass::clean_dependent_nmethods() {
  1873   assert_locked_or_safepoint(CodeCache_lock);
  1875   if (has_unloaded_dependent()) {
  1876     nmethodBucket* b = _dependencies;
  1877     nmethodBucket* last = NULL;
  1878     while (b != NULL) {
  1879       assert(b->count() >= 0, err_msg("bucket count: %d", b->count()));
  1881       nmethodBucket* next = b->next();
  1883       if (b->count() == 0) {
  1884         if (last == NULL) {
  1885           _dependencies = next;
  1886         } else {
  1887           last->set_next(next);
  1889         delete b;
  1890         // last stays the same.
  1891       } else {
  1892         last = b;
  1895       b = next;
  1897     set_has_unloaded_dependent(false);
  1899 #ifdef ASSERT
  1900   else {
  1901     // Verification
  1902     for (nmethodBucket* b = _dependencies; b != NULL; b = b->next()) {
  1903       assert(b->count() >= 0, err_msg("bucket count: %d", b->count()));
  1904       assert(b->count() != 0, "empty buckets need to be cleaned");
  1907 #endif
  1910 //
  1911 // Add an nmethodBucket to the list of dependencies for this nmethod.
  1912 // It's possible that an nmethod has multiple dependencies on this klass
  1913 // so a count is kept for each bucket to guarantee that creation and
  1914 // deletion of dependencies is consistent.
  1915 //
  1916 void InstanceKlass::add_dependent_nmethod(nmethod* nm) {
  1917   assert_locked_or_safepoint(CodeCache_lock);
  1918   nmethodBucket* b = _dependencies;
  1919   nmethodBucket* last = NULL;
  1920   while (b != NULL) {
  1921     if (nm == b->get_nmethod()) {
  1922       b->increment();
  1923       return;
  1925     b = b->next();
  1927   _dependencies = new nmethodBucket(nm, _dependencies);
  1931 //
  1932 // Decrement count of the nmethod in the dependency list and remove
  1933 // the bucket competely when the count goes to 0.  This method must
  1934 // find a corresponding bucket otherwise there's a bug in the
  1935 // recording of dependecies.
  1936 //
  1937 void InstanceKlass::remove_dependent_nmethod(nmethod* nm) {
  1938   assert_locked_or_safepoint(CodeCache_lock);
  1939   nmethodBucket* b = _dependencies;
  1940   nmethodBucket* last = NULL;
  1941   while (b != NULL) {
  1942     if (nm == b->get_nmethod()) {
  1943       int val = b->decrement();
  1944       guarantee(val >= 0, err_msg("Underflow: %d", val));
  1945       if (val == 0) {
  1946         set_has_unloaded_dependent(true);
  1948       return;
  1950     last = b;
  1951     b = b->next();
  1953 #ifdef ASSERT
  1954   tty->print_cr("### %s can't find dependent nmethod:", this->external_name());
  1955   nm->print();
  1956 #endif // ASSERT
  1957   ShouldNotReachHere();
  1961 #ifndef PRODUCT
  1962 void InstanceKlass::print_dependent_nmethods(bool verbose) {
  1963   nmethodBucket* b = _dependencies;
  1964   int idx = 0;
  1965   while (b != NULL) {
  1966     nmethod* nm = b->get_nmethod();
  1967     tty->print("[%d] count=%d { ", idx++, b->count());
  1968     if (!verbose) {
  1969       nm->print_on(tty, "nmethod");
  1970       tty->print_cr(" } ");
  1971     } else {
  1972       nm->print();
  1973       nm->print_dependencies();
  1974       tty->print_cr("--- } ");
  1976     b = b->next();
  1981 bool InstanceKlass::is_dependent_nmethod(nmethod* nm) {
  1982   nmethodBucket* b = _dependencies;
  1983   while (b != NULL) {
  1984     if (nm == b->get_nmethod()) {
  1985 #ifdef ASSERT
  1986       int count = b->count();
  1987       assert(count >= 0, err_msg("count shouldn't be negative: %d", count));
  1988 #endif
  1989       return true;
  1991     b = b->next();
  1993   return false;
  1995 #endif //PRODUCT
  1998 // Garbage collection
  2000 #ifdef ASSERT
  2001 template <class T> void assert_is_in(T *p) {
  2002   T heap_oop = oopDesc::load_heap_oop(p);
  2003   if (!oopDesc::is_null(heap_oop)) {
  2004     oop o = oopDesc::decode_heap_oop_not_null(heap_oop);
  2005     assert(Universe::heap()->is_in(o), "should be in heap");
  2008 template <class T> void assert_is_in_closed_subset(T *p) {
  2009   T heap_oop = oopDesc::load_heap_oop(p);
  2010   if (!oopDesc::is_null(heap_oop)) {
  2011     oop o = oopDesc::decode_heap_oop_not_null(heap_oop);
  2012     assert(Universe::heap()->is_in_closed_subset(o),
  2013            err_msg("should be in closed *p " INTPTR_FORMAT " " INTPTR_FORMAT, (address)p, (address)o));
  2016 template <class T> void assert_is_in_reserved(T *p) {
  2017   T heap_oop = oopDesc::load_heap_oop(p);
  2018   if (!oopDesc::is_null(heap_oop)) {
  2019     oop o = oopDesc::decode_heap_oop_not_null(heap_oop);
  2020     assert(Universe::heap()->is_in_reserved(o), "should be in reserved");
  2023 template <class T> void assert_nothing(T *p) {}
  2025 #else
  2026 template <class T> void assert_is_in(T *p) {}
  2027 template <class T> void assert_is_in_closed_subset(T *p) {}
  2028 template <class T> void assert_is_in_reserved(T *p) {}
  2029 template <class T> void assert_nothing(T *p) {}
  2030 #endif // ASSERT
  2032 //
  2033 // Macros that iterate over areas of oops which are specialized on type of
  2034 // oop pointer either narrow or wide, depending on UseCompressedOops
  2035 //
  2036 // Parameters are:
  2037 //   T         - type of oop to point to (either oop or narrowOop)
  2038 //   start_p   - starting pointer for region to iterate over
  2039 //   count     - number of oops or narrowOops to iterate over
  2040 //   do_oop    - action to perform on each oop (it's arbitrary C code which
  2041 //               makes it more efficient to put in a macro rather than making
  2042 //               it a template function)
  2043 //   assert_fn - assert function which is template function because performance
  2044 //               doesn't matter when enabled.
  2045 #define InstanceKlass_SPECIALIZED_OOP_ITERATE( \
  2046   T, start_p, count, do_oop,                \
  2047   assert_fn)                                \
  2048 {                                           \
  2049   T* p         = (T*)(start_p);             \
  2050   T* const end = p + (count);               \
  2051   while (p < end) {                         \
  2052     (assert_fn)(p);                         \
  2053     do_oop;                                 \
  2054     ++p;                                    \
  2055   }                                         \
  2058 #define InstanceKlass_SPECIALIZED_OOP_REVERSE_ITERATE( \
  2059   T, start_p, count, do_oop,                \
  2060   assert_fn)                                \
  2061 {                                           \
  2062   T* const start = (T*)(start_p);           \
  2063   T*       p     = start + (count);         \
  2064   while (start < p) {                       \
  2065     --p;                                    \
  2066     (assert_fn)(p);                         \
  2067     do_oop;                                 \
  2068   }                                         \
  2071 #define InstanceKlass_SPECIALIZED_BOUNDED_OOP_ITERATE( \
  2072   T, start_p, count, low, high,             \
  2073   do_oop, assert_fn)                        \
  2074 {                                           \
  2075   T* const l = (T*)(low);                   \
  2076   T* const h = (T*)(high);                  \
  2077   assert(mask_bits((intptr_t)l, sizeof(T)-1) == 0 && \
  2078          mask_bits((intptr_t)h, sizeof(T)-1) == 0,   \
  2079          "bounded region must be properly aligned"); \
  2080   T* p       = (T*)(start_p);               \
  2081   T* end     = p + (count);                 \
  2082   if (p < l) p = l;                         \
  2083   if (end > h) end = h;                     \
  2084   while (p < end) {                         \
  2085     (assert_fn)(p);                         \
  2086     do_oop;                                 \
  2087     ++p;                                    \
  2088   }                                         \
  2092 // The following macros call specialized macros, passing either oop or
  2093 // narrowOop as the specialization type.  These test the UseCompressedOops
  2094 // flag.
  2095 #define InstanceKlass_OOP_MAP_ITERATE(obj, do_oop, assert_fn)            \
  2096 {                                                                        \
  2097   /* Compute oopmap block range. The common case                         \
  2098      is nonstatic_oop_map_size == 1. */                                  \
  2099   OopMapBlock* map           = start_of_nonstatic_oop_maps();            \
  2100   OopMapBlock* const end_map = map + nonstatic_oop_map_count();          \
  2101   if (UseCompressedOops) {                                               \
  2102     while (map < end_map) {                                              \
  2103       InstanceKlass_SPECIALIZED_OOP_ITERATE(narrowOop,                   \
  2104         obj->obj_field_addr<narrowOop>(map->offset()), map->count(),     \
  2105         do_oop, assert_fn)                                               \
  2106       ++map;                                                             \
  2107     }                                                                    \
  2108   } else {                                                               \
  2109     while (map < end_map) {                                              \
  2110       InstanceKlass_SPECIALIZED_OOP_ITERATE(oop,                         \
  2111         obj->obj_field_addr<oop>(map->offset()), map->count(),           \
  2112         do_oop, assert_fn)                                               \
  2113       ++map;                                                             \
  2114     }                                                                    \
  2115   }                                                                      \
  2118 #define InstanceKlass_OOP_MAP_REVERSE_ITERATE(obj, do_oop, assert_fn)    \
  2119 {                                                                        \
  2120   OopMapBlock* const start_map = start_of_nonstatic_oop_maps();          \
  2121   OopMapBlock* map             = start_map + nonstatic_oop_map_count();  \
  2122   if (UseCompressedOops) {                                               \
  2123     while (start_map < map) {                                            \
  2124       --map;                                                             \
  2125       InstanceKlass_SPECIALIZED_OOP_REVERSE_ITERATE(narrowOop,           \
  2126         obj->obj_field_addr<narrowOop>(map->offset()), map->count(),     \
  2127         do_oop, assert_fn)                                               \
  2128     }                                                                    \
  2129   } else {                                                               \
  2130     while (start_map < map) {                                            \
  2131       --map;                                                             \
  2132       InstanceKlass_SPECIALIZED_OOP_REVERSE_ITERATE(oop,                 \
  2133         obj->obj_field_addr<oop>(map->offset()), map->count(),           \
  2134         do_oop, assert_fn)                                               \
  2135     }                                                                    \
  2136   }                                                                      \
  2139 #define InstanceKlass_BOUNDED_OOP_MAP_ITERATE(obj, low, high, do_oop,    \
  2140                                               assert_fn)                 \
  2141 {                                                                        \
  2142   /* Compute oopmap block range. The common case is                      \
  2143      nonstatic_oop_map_size == 1, so we accept the                       \
  2144      usually non-existent extra overhead of examining                    \
  2145      all the maps. */                                                    \
  2146   OopMapBlock* map           = start_of_nonstatic_oop_maps();            \
  2147   OopMapBlock* const end_map = map + nonstatic_oop_map_count();          \
  2148   if (UseCompressedOops) {                                               \
  2149     while (map < end_map) {                                              \
  2150       InstanceKlass_SPECIALIZED_BOUNDED_OOP_ITERATE(narrowOop,           \
  2151         obj->obj_field_addr<narrowOop>(map->offset()), map->count(),     \
  2152         low, high,                                                       \
  2153         do_oop, assert_fn)                                               \
  2154       ++map;                                                             \
  2155     }                                                                    \
  2156   } else {                                                               \
  2157     while (map < end_map) {                                              \
  2158       InstanceKlass_SPECIALIZED_BOUNDED_OOP_ITERATE(oop,                 \
  2159         obj->obj_field_addr<oop>(map->offset()), map->count(),           \
  2160         low, high,                                                       \
  2161         do_oop, assert_fn)                                               \
  2162       ++map;                                                             \
  2163     }                                                                    \
  2164   }                                                                      \
  2167 void InstanceKlass::oop_follow_contents(oop obj) {
  2168   assert(obj != NULL, "can't follow the content of NULL object");
  2169   MarkSweep::follow_klass(obj->klass());
  2170   InstanceKlass_OOP_MAP_ITERATE( \
  2171     obj, \
  2172     MarkSweep::mark_and_push(p), \
  2173     assert_is_in_closed_subset)
  2176 #if INCLUDE_ALL_GCS
  2177 void InstanceKlass::oop_follow_contents(ParCompactionManager* cm,
  2178                                         oop obj) {
  2179   assert(obj != NULL, "can't follow the content of NULL object");
  2180   PSParallelCompact::follow_klass(cm, obj->klass());
  2181   // Only mark the header and let the scan of the meta-data mark
  2182   // everything else.
  2183   InstanceKlass_OOP_MAP_ITERATE( \
  2184     obj, \
  2185     PSParallelCompact::mark_and_push(cm, p), \
  2186     assert_is_in)
  2188 #endif // INCLUDE_ALL_GCS
  2190 // closure's do_metadata() method dictates whether the given closure should be
  2191 // applied to the klass ptr in the object header.
  2193 #define InstanceKlass_OOP_OOP_ITERATE_DEFN(OopClosureType, nv_suffix)        \
  2195 int InstanceKlass::oop_oop_iterate##nv_suffix(oop obj, OopClosureType* closure) { \
  2196   SpecializationStats::record_iterate_call##nv_suffix(SpecializationStats::ik);\
  2197   /* header */                                                          \
  2198   if_do_metadata_checked(closure, nv_suffix) {                          \
  2199     closure->do_klass##nv_suffix(obj->klass());                         \
  2200   }                                                                     \
  2201   InstanceKlass_OOP_MAP_ITERATE(                                        \
  2202     obj,                                                                \
  2203     SpecializationStats::                                               \
  2204       record_do_oop_call##nv_suffix(SpecializationStats::ik);           \
  2205     (closure)->do_oop##nv_suffix(p),                                    \
  2206     assert_is_in_closed_subset)                                         \
  2207   return size_helper();                                                 \
  2210 #if INCLUDE_ALL_GCS
  2211 #define InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DEFN(OopClosureType, nv_suffix) \
  2213 int InstanceKlass::oop_oop_iterate_backwards##nv_suffix(oop obj,                \
  2214                                               OopClosureType* closure) {        \
  2215   SpecializationStats::record_iterate_call##nv_suffix(SpecializationStats::ik); \
  2217   assert_should_ignore_metadata(closure, nv_suffix);                            \
  2219   /* instance variables */                                                      \
  2220   InstanceKlass_OOP_MAP_REVERSE_ITERATE(                                        \
  2221     obj,                                                                        \
  2222     SpecializationStats::record_do_oop_call##nv_suffix(SpecializationStats::ik);\
  2223     (closure)->do_oop##nv_suffix(p),                                            \
  2224     assert_is_in_closed_subset)                                                 \
  2225    return size_helper();                                                        \
  2227 #endif // INCLUDE_ALL_GCS
  2229 #define InstanceKlass_OOP_OOP_ITERATE_DEFN_m(OopClosureType, nv_suffix) \
  2231 int InstanceKlass::oop_oop_iterate##nv_suffix##_m(oop obj,              \
  2232                                                   OopClosureType* closure, \
  2233                                                   MemRegion mr) {          \
  2234   SpecializationStats::record_iterate_call##nv_suffix(SpecializationStats::ik);\
  2235   if_do_metadata_checked(closure, nv_suffix) {                           \
  2236     if (mr.contains(obj)) {                                              \
  2237       closure->do_klass##nv_suffix(obj->klass());                        \
  2238     }                                                                    \
  2239   }                                                                      \
  2240   InstanceKlass_BOUNDED_OOP_MAP_ITERATE(                                 \
  2241     obj, mr.start(), mr.end(),                                           \
  2242     (closure)->do_oop##nv_suffix(p),                                     \
  2243     assert_is_in_closed_subset)                                          \
  2244   return size_helper();                                                  \
  2247 ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_DEFN)
  2248 ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceKlass_OOP_OOP_ITERATE_DEFN)
  2249 ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_DEFN_m)
  2250 ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceKlass_OOP_OOP_ITERATE_DEFN_m)
  2251 #if INCLUDE_ALL_GCS
  2252 ALL_OOP_OOP_ITERATE_CLOSURES_1(InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DEFN)
  2253 ALL_OOP_OOP_ITERATE_CLOSURES_2(InstanceKlass_OOP_OOP_ITERATE_BACKWARDS_DEFN)
  2254 #endif // INCLUDE_ALL_GCS
  2256 int InstanceKlass::oop_adjust_pointers(oop obj) {
  2257   int size = size_helper();
  2258   InstanceKlass_OOP_MAP_ITERATE( \
  2259     obj, \
  2260     MarkSweep::adjust_pointer(p), \
  2261     assert_is_in)
  2262   return size;
  2265 #if INCLUDE_ALL_GCS
  2266 void InstanceKlass::oop_push_contents(PSPromotionManager* pm, oop obj) {
  2267   InstanceKlass_OOP_MAP_REVERSE_ITERATE( \
  2268     obj, \
  2269     if (PSScavenge::should_scavenge(p)) { \
  2270       pm->claim_or_forward_depth(p); \
  2271     }, \
  2272     assert_nothing )
  2275 int InstanceKlass::oop_update_pointers(ParCompactionManager* cm, oop obj) {
  2276   int size = size_helper();
  2277   InstanceKlass_OOP_MAP_ITERATE( \
  2278     obj, \
  2279     PSParallelCompact::adjust_pointer(p), \
  2280     assert_is_in)
  2281   return size;
  2284 #endif // INCLUDE_ALL_GCS
  2286 void InstanceKlass::clean_implementors_list(BoolObjectClosure* is_alive) {
  2287   assert(class_loader_data()->is_alive(is_alive), "this klass should be live");
  2288   if (is_interface()) {
  2289     if (ClassUnloading) {
  2290       Klass* impl = implementor();
  2291       if (impl != NULL) {
  2292         if (!impl->is_loader_alive(is_alive)) {
  2293           // remove this guy
  2294           Klass** klass = adr_implementor();
  2295           assert(klass != NULL, "null klass");
  2296           if (klass != NULL) {
  2297             *klass = NULL;
  2305 void InstanceKlass::clean_method_data(BoolObjectClosure* is_alive) {
  2306   for (int m = 0; m < methods()->length(); m++) {
  2307     MethodData* mdo = methods()->at(m)->method_data();
  2308     if (mdo != NULL) {
  2309       mdo->clean_method_data(is_alive);
  2315 static void remove_unshareable_in_class(Klass* k) {
  2316   // remove klass's unshareable info
  2317   k->remove_unshareable_info();
  2320 void InstanceKlass::remove_unshareable_info() {
  2321   Klass::remove_unshareable_info();
  2322   // Unlink the class
  2323   if (is_linked()) {
  2324     unlink_class();
  2326   init_implementor();
  2328   constants()->remove_unshareable_info();
  2330   for (int i = 0; i < methods()->length(); i++) {
  2331     Method* m = methods()->at(i);
  2332     m->remove_unshareable_info();
  2335   // do array classes also.
  2336   array_klasses_do(remove_unshareable_in_class);
  2339 static void restore_unshareable_in_class(Klass* k, TRAPS) {
  2340   // Array classes have null protection domain.
  2341   // --> see ArrayKlass::complete_create_array_klass()
  2342   k->restore_unshareable_info(ClassLoaderData::the_null_class_loader_data(), Handle(), CHECK);
  2345 void InstanceKlass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain, TRAPS) {
  2346   Klass::restore_unshareable_info(loader_data, protection_domain, CHECK);
  2347   instanceKlassHandle ik(THREAD, this);
  2349   Array<Method*>* methods = ik->methods();
  2350   int num_methods = methods->length();
  2351   for (int index2 = 0; index2 < num_methods; ++index2) {
  2352     methodHandle m(THREAD, methods->at(index2));
  2353     m->restore_unshareable_info(CHECK);
  2355   if (JvmtiExport::has_redefined_a_class()) {
  2356     // Reinitialize vtable because RedefineClasses may have changed some
  2357     // entries in this vtable for super classes so the CDS vtable might
  2358     // point to old or obsolete entries.  RedefineClasses doesn't fix up
  2359     // vtables in the shared system dictionary, only the main one.
  2360     // It also redefines the itable too so fix that too.
  2361     ResourceMark rm(THREAD);
  2362     ik->vtable()->initialize_vtable(false, CHECK);
  2363     ik->itable()->initialize_itable(false, CHECK);
  2366   // restore constant pool resolved references
  2367   ik->constants()->restore_unshareable_info(CHECK);
  2369   ik->array_klasses_do(restore_unshareable_in_class, CHECK);
  2372 // returns true IFF is_in_error_state() has been changed as a result of this call.
  2373 bool InstanceKlass::check_sharing_error_state() {
  2374   assert(DumpSharedSpaces, "should only be called during dumping");
  2375   bool old_state = is_in_error_state();
  2377   if (!is_in_error_state()) {
  2378     bool bad = false;
  2379     for (InstanceKlass* sup = java_super(); sup; sup = sup->java_super()) {
  2380       if (sup->is_in_error_state()) {
  2381         bad = true;
  2382         break;
  2385     if (!bad) {
  2386       Array<Klass*>* interfaces = transitive_interfaces();
  2387       for (int i = 0; i < interfaces->length(); i++) {
  2388         Klass* iface = interfaces->at(i);
  2389         if (InstanceKlass::cast(iface)->is_in_error_state()) {
  2390           bad = true;
  2391           break;
  2396     if (bad) {
  2397       set_in_error_state();
  2401   return (old_state != is_in_error_state());
  2404 static void clear_all_breakpoints(Method* m) {
  2405   m->clear_all_breakpoints();
  2409 void InstanceKlass::notify_unload_class(InstanceKlass* ik) {
  2410   // notify the debugger
  2411   if (JvmtiExport::should_post_class_unload()) {
  2412     JvmtiExport::post_class_unload(ik);
  2415   // notify ClassLoadingService of class unload
  2416   ClassLoadingService::notify_class_unloaded(ik);
  2419 void InstanceKlass::release_C_heap_structures(InstanceKlass* ik) {
  2420   // Clean up C heap
  2421   ik->release_C_heap_structures();
  2422   ik->constants()->release_C_heap_structures();
  2425 void InstanceKlass::release_C_heap_structures() {
  2427   // Can't release the constant pool here because the constant pool can be
  2428   // deallocated separately from the InstanceKlass for default methods and
  2429   // redefine classes.
  2431   // Deallocate oop map cache
  2432   if (_oop_map_cache != NULL) {
  2433     delete _oop_map_cache;
  2434     _oop_map_cache = NULL;
  2437   // Deallocate JNI identifiers for jfieldIDs
  2438   JNIid::deallocate(jni_ids());
  2439   set_jni_ids(NULL);
  2441   jmethodID* jmeths = methods_jmethod_ids_acquire();
  2442   if (jmeths != (jmethodID*)NULL) {
  2443     release_set_methods_jmethod_ids(NULL);
  2444     FreeHeap(jmeths);
  2447   // Deallocate MemberNameTable
  2449     Mutex* lock_or_null = SafepointSynchronize::is_at_safepoint() ? NULL : MemberNameTable_lock;
  2450     MutexLockerEx ml(lock_or_null, Mutex::_no_safepoint_check_flag);
  2451     MemberNameTable* mnt = member_names();
  2452     if (mnt != NULL) {
  2453       delete mnt;
  2454       set_member_names(NULL);
  2458   // release dependencies
  2459   nmethodBucket* b = _dependencies;
  2460   _dependencies = NULL;
  2461   while (b != NULL) {
  2462     nmethodBucket* next = b->next();
  2463     delete b;
  2464     b = next;
  2467   // Deallocate breakpoint records
  2468   if (breakpoints() != 0x0) {
  2469     methods_do(clear_all_breakpoints);
  2470     assert(breakpoints() == 0x0, "should have cleared breakpoints");
  2473   // deallocate information about previous versions
  2474   if (_previous_versions != NULL) {
  2475     for (int i = _previous_versions->length() - 1; i >= 0; i--) {
  2476       PreviousVersionNode * pv_node = _previous_versions->at(i);
  2477       delete pv_node;
  2479     delete _previous_versions;
  2480     _previous_versions = NULL;
  2483   // deallocate the cached class file
  2484   if (_cached_class_file != NULL) {
  2485     os::free(_cached_class_file, mtClass);
  2486     _cached_class_file = NULL;
  2489   // Decrement symbol reference counts associated with the unloaded class.
  2490   if (_name != NULL) _name->decrement_refcount();
  2491   // unreference array name derived from this class name (arrays of an unloaded
  2492   // class can't be referenced anymore).
  2493   if (_array_name != NULL)  _array_name->decrement_refcount();
  2494   if (_source_debug_extension != NULL) FREE_C_HEAP_ARRAY(char, _source_debug_extension, mtClass);
  2496   assert(_total_instanceKlass_count >= 1, "Sanity check");
  2497   Atomic::dec(&_total_instanceKlass_count);
  2500 void InstanceKlass::set_source_debug_extension(char* array, int length) {
  2501   if (array == NULL) {
  2502     _source_debug_extension = NULL;
  2503   } else {
  2504     // Adding one to the attribute length in order to store a null terminator
  2505     // character could cause an overflow because the attribute length is
  2506     // already coded with an u4 in the classfile, but in practice, it's
  2507     // unlikely to happen.
  2508     assert((length+1) > length, "Overflow checking");
  2509     char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass);
  2510     for (int i = 0; i < length; i++) {
  2511       sde[i] = array[i];
  2513     sde[length] = '\0';
  2514     _source_debug_extension = sde;
  2518 address InstanceKlass::static_field_addr(int offset) {
  2519   return (address)(offset + InstanceMirrorKlass::offset_of_static_fields() + cast_from_oop<intptr_t>(java_mirror()));
  2523 const char* InstanceKlass::signature_name() const {
  2524   int hash_len = 0;
  2525   char hash_buf[40];
  2527   // If this is an anonymous class, append a hash to make the name unique
  2528   if (is_anonymous()) {
  2529     assert(EnableInvokeDynamic, "EnableInvokeDynamic was not set.");
  2530     intptr_t hash = (java_mirror() != NULL) ? java_mirror()->identity_hash() : 0;
  2531     sprintf(hash_buf, "/" UINTX_FORMAT, (uintx)hash);
  2532     hash_len = (int)strlen(hash_buf);
  2535   // Get the internal name as a c string
  2536   const char* src = (const char*) (name()->as_C_string());
  2537   const int src_length = (int)strlen(src);
  2539   char* dest = NEW_RESOURCE_ARRAY(char, src_length + hash_len + 3);
  2541   // Add L as type indicator
  2542   int dest_index = 0;
  2543   dest[dest_index++] = 'L';
  2545   // Add the actual class name
  2546   for (int src_index = 0; src_index < src_length; ) {
  2547     dest[dest_index++] = src[src_index++];
  2550   // If we have a hash, append it
  2551   for (int hash_index = 0; hash_index < hash_len; ) {
  2552     dest[dest_index++] = hash_buf[hash_index++];
  2555   // Add the semicolon and the NULL
  2556   dest[dest_index++] = ';';
  2557   dest[dest_index] = '\0';
  2558   return dest;
  2561 // different verisons of is_same_class_package
  2562 bool InstanceKlass::is_same_class_package(Klass* class2) {
  2563   Klass* class1 = this;
  2564   oop classloader1 = InstanceKlass::cast(class1)->class_loader();
  2565   Symbol* classname1 = class1->name();
  2567   if (class2->oop_is_objArray()) {
  2568     class2 = ObjArrayKlass::cast(class2)->bottom_klass();
  2570   oop classloader2;
  2571   if (class2->oop_is_instance()) {
  2572     classloader2 = InstanceKlass::cast(class2)->class_loader();
  2573   } else {
  2574     assert(class2->oop_is_typeArray(), "should be type array");
  2575     classloader2 = NULL;
  2577   Symbol* classname2 = class2->name();
  2579   return InstanceKlass::is_same_class_package(classloader1, classname1,
  2580                                               classloader2, classname2);
  2583 bool InstanceKlass::is_same_class_package(oop classloader2, Symbol* classname2) {
  2584   Klass* class1 = this;
  2585   oop classloader1 = InstanceKlass::cast(class1)->class_loader();
  2586   Symbol* classname1 = class1->name();
  2588   return InstanceKlass::is_same_class_package(classloader1, classname1,
  2589                                               classloader2, classname2);
  2592 // return true if two classes are in the same package, classloader
  2593 // and classname information is enough to determine a class's package
  2594 bool InstanceKlass::is_same_class_package(oop class_loader1, Symbol* class_name1,
  2595                                           oop class_loader2, Symbol* class_name2) {
  2596   if (class_loader1 != class_loader2) {
  2597     return false;
  2598   } else if (class_name1 == class_name2) {
  2599     return true;                // skip painful bytewise comparison
  2600   } else {
  2601     ResourceMark rm;
  2603     // The Symbol*'s are in UTF8 encoding. Since we only need to check explicitly
  2604     // for ASCII characters ('/', 'L', '['), we can keep them in UTF8 encoding.
  2605     // Otherwise, we just compare jbyte values between the strings.
  2606     const jbyte *name1 = class_name1->base();
  2607     const jbyte *name2 = class_name2->base();
  2609     const jbyte *last_slash1 = UTF8::strrchr(name1, class_name1->utf8_length(), '/');
  2610     const jbyte *last_slash2 = UTF8::strrchr(name2, class_name2->utf8_length(), '/');
  2612     if ((last_slash1 == NULL) || (last_slash2 == NULL)) {
  2613       // One of the two doesn't have a package.  Only return true
  2614       // if the other one also doesn't have a package.
  2615       return last_slash1 == last_slash2;
  2616     } else {
  2617       // Skip over '['s
  2618       if (*name1 == '[') {
  2619         do {
  2620           name1++;
  2621         } while (*name1 == '[');
  2622         if (*name1 != 'L') {
  2623           // Something is terribly wrong.  Shouldn't be here.
  2624           return false;
  2627       if (*name2 == '[') {
  2628         do {
  2629           name2++;
  2630         } while (*name2 == '[');
  2631         if (*name2 != 'L') {
  2632           // Something is terribly wrong.  Shouldn't be here.
  2633           return false;
  2637       // Check that package part is identical
  2638       int length1 = last_slash1 - name1;
  2639       int length2 = last_slash2 - name2;
  2641       return UTF8::equal(name1, length1, name2, length2);
  2646 // Returns true iff super_method can be overridden by a method in targetclassname
  2647 // See JSL 3rd edition 8.4.6.1
  2648 // Assumes name-signature match
  2649 // "this" is InstanceKlass of super_method which must exist
  2650 // note that the InstanceKlass of the method in the targetclassname has not always been created yet
  2651 bool InstanceKlass::is_override(methodHandle super_method, Handle targetclassloader, Symbol* targetclassname, TRAPS) {
  2652    // Private methods can not be overridden
  2653    if (super_method->is_private()) {
  2654      return false;
  2656    // If super method is accessible, then override
  2657    if ((super_method->is_protected()) ||
  2658        (super_method->is_public())) {
  2659      return true;
  2661    // Package-private methods are not inherited outside of package
  2662    assert(super_method->is_package_private(), "must be package private");
  2663    return(is_same_class_package(targetclassloader(), targetclassname));
  2666 /* defined for now in jvm.cpp, for historical reasons *--
  2667 Klass* InstanceKlass::compute_enclosing_class_impl(instanceKlassHandle self,
  2668                                                      Symbol*& simple_name_result, TRAPS) {
  2669   ...
  2671 */
  2673 // tell if two classes have the same enclosing class (at package level)
  2674 bool InstanceKlass::is_same_package_member_impl(instanceKlassHandle class1,
  2675                                                 Klass* class2_oop, TRAPS) {
  2676   if (class2_oop == class1())                       return true;
  2677   if (!class2_oop->oop_is_instance())  return false;
  2678   instanceKlassHandle class2(THREAD, class2_oop);
  2680   // must be in same package before we try anything else
  2681   if (!class1->is_same_class_package(class2->class_loader(), class2->name()))
  2682     return false;
  2684   // As long as there is an outer1.getEnclosingClass,
  2685   // shift the search outward.
  2686   instanceKlassHandle outer1 = class1;
  2687   for (;;) {
  2688     // As we walk along, look for equalities between outer1 and class2.
  2689     // Eventually, the walks will terminate as outer1 stops
  2690     // at the top-level class around the original class.
  2691     bool ignore_inner_is_member;
  2692     Klass* next = outer1->compute_enclosing_class(&ignore_inner_is_member,
  2693                                                     CHECK_false);
  2694     if (next == NULL)  break;
  2695     if (next == class2())  return true;
  2696     outer1 = instanceKlassHandle(THREAD, next);
  2699   // Now do the same for class2.
  2700   instanceKlassHandle outer2 = class2;
  2701   for (;;) {
  2702     bool ignore_inner_is_member;
  2703     Klass* next = outer2->compute_enclosing_class(&ignore_inner_is_member,
  2704                                                     CHECK_false);
  2705     if (next == NULL)  break;
  2706     // Might as well check the new outer against all available values.
  2707     if (next == class1())  return true;
  2708     if (next == outer1())  return true;
  2709     outer2 = instanceKlassHandle(THREAD, next);
  2712   // If by this point we have not found an equality between the
  2713   // two classes, we know they are in separate package members.
  2714   return false;
  2718 jint InstanceKlass::compute_modifier_flags(TRAPS) const {
  2719   jint access = access_flags().as_int();
  2721   // But check if it happens to be member class.
  2722   instanceKlassHandle ik(THREAD, this);
  2723   InnerClassesIterator iter(ik);
  2724   for (; !iter.done(); iter.next()) {
  2725     int ioff = iter.inner_class_info_index();
  2726     // Inner class attribute can be zero, skip it.
  2727     // Strange but true:  JVM spec. allows null inner class refs.
  2728     if (ioff == 0) continue;
  2730     // only look at classes that are already loaded
  2731     // since we are looking for the flags for our self.
  2732     Symbol* inner_name = ik->constants()->klass_name_at(ioff);
  2733     if ((ik->name() == inner_name)) {
  2734       // This is really a member class.
  2735       access = iter.inner_access_flags();
  2736       break;
  2739   // Remember to strip ACC_SUPER bit
  2740   return (access & (~JVM_ACC_SUPER)) & JVM_ACC_WRITTEN_FLAGS;
  2743 jint InstanceKlass::jvmti_class_status() const {
  2744   jint result = 0;
  2746   if (is_linked()) {
  2747     result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED;
  2750   if (is_initialized()) {
  2751     assert(is_linked(), "Class status is not consistent");
  2752     result |= JVMTI_CLASS_STATUS_INITIALIZED;
  2754   if (is_in_error_state()) {
  2755     result |= JVMTI_CLASS_STATUS_ERROR;
  2757   return result;
  2760 Method* InstanceKlass::method_at_itable(Klass* holder, int index, TRAPS) {
  2761   itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
  2762   int method_table_offset_in_words = ioe->offset()/wordSize;
  2763   int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words())
  2764                        / itableOffsetEntry::size();
  2766   for (int cnt = 0 ; ; cnt ++, ioe ++) {
  2767     // If the interface isn't implemented by the receiver class,
  2768     // the VM should throw IncompatibleClassChangeError.
  2769     if (cnt >= nof_interfaces) {
  2770       THROW_NULL(vmSymbols::java_lang_IncompatibleClassChangeError());
  2773     Klass* ik = ioe->interface_klass();
  2774     if (ik == holder) break;
  2777   itableMethodEntry* ime = ioe->first_method_entry(this);
  2778   Method* m = ime[index].method();
  2779   if (m == NULL) {
  2780     THROW_NULL(vmSymbols::java_lang_AbstractMethodError());
  2782   return m;
  2786 #if INCLUDE_JVMTI
  2787 // update default_methods for redefineclasses for methods that are
  2788 // not yet in the vtable due to concurrent subclass define and superinterface
  2789 // redefinition
  2790 // Note: those in the vtable, should have been updated via adjust_method_entries
  2791 void InstanceKlass::adjust_default_methods(Method** old_methods, Method** new_methods,
  2792                                            int methods_length, bool* trace_name_printed) {
  2793   // search the default_methods for uses of either obsolete or EMCP methods
  2794   if (default_methods() != NULL) {
  2795     for (int j = 0; j < methods_length; j++) {
  2796       Method* old_method = old_methods[j];
  2797       Method* new_method = new_methods[j];
  2799       for (int index = 0; index < default_methods()->length(); index ++) {
  2800         if (default_methods()->at(index) == old_method) {
  2801           default_methods()->at_put(index, new_method);
  2802           if (RC_TRACE_IN_RANGE(0x00100000, 0x00400000)) {
  2803             if (!(*trace_name_printed)) {
  2804               // RC_TRACE_MESG macro has an embedded ResourceMark
  2805               RC_TRACE_MESG(("adjust: klassname=%s default methods from name=%s",
  2806                              external_name(),
  2807                              old_method->method_holder()->external_name()));
  2808               *trace_name_printed = true;
  2810             RC_TRACE(0x00100000, ("default method update: %s(%s) ",
  2811                                   new_method->name()->as_C_string(),
  2812                                   new_method->signature()->as_C_string()));
  2819 #endif // INCLUDE_JVMTI
  2821 // On-stack replacement stuff
  2822 void InstanceKlass::add_osr_nmethod(nmethod* n) {
  2823   // only one compilation can be active
  2824   NEEDS_CLEANUP
  2825   // This is a short non-blocking critical region, so the no safepoint check is ok.
  2826   OsrList_lock->lock_without_safepoint_check();
  2827   assert(n->is_osr_method(), "wrong kind of nmethod");
  2828   n->set_osr_link(osr_nmethods_head());
  2829   set_osr_nmethods_head(n);
  2830   // Raise the highest osr level if necessary
  2831   if (TieredCompilation) {
  2832     Method* m = n->method();
  2833     m->set_highest_osr_comp_level(MAX2(m->highest_osr_comp_level(), n->comp_level()));
  2835   // Remember to unlock again
  2836   OsrList_lock->unlock();
  2838   // Get rid of the osr methods for the same bci that have lower levels.
  2839   if (TieredCompilation) {
  2840     for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) {
  2841       nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true);
  2842       if (inv != NULL && inv->is_in_use()) {
  2843         inv->make_not_entrant();
  2850 void InstanceKlass::remove_osr_nmethod(nmethod* n) {
  2851   // This is a short non-blocking critical region, so the no safepoint check is ok.
  2852   OsrList_lock->lock_without_safepoint_check();
  2853   assert(n->is_osr_method(), "wrong kind of nmethod");
  2854   nmethod* last = NULL;
  2855   nmethod* cur  = osr_nmethods_head();
  2856   int max_level = CompLevel_none;  // Find the max comp level excluding n
  2857   Method* m = n->method();
  2858   // Search for match
  2859   while(cur != NULL && cur != n) {
  2860     if (TieredCompilation && m == cur->method()) {
  2861       // Find max level before n
  2862       max_level = MAX2(max_level, cur->comp_level());
  2864     last = cur;
  2865     cur = cur->osr_link();
  2867   nmethod* next = NULL;
  2868   if (cur == n) {
  2869     next = cur->osr_link();
  2870     if (last == NULL) {
  2871       // Remove first element
  2872       set_osr_nmethods_head(next);
  2873     } else {
  2874       last->set_osr_link(next);
  2877   n->set_osr_link(NULL);
  2878   if (TieredCompilation) {
  2879     cur = next;
  2880     while (cur != NULL) {
  2881       // Find max level after n
  2882       if (m == cur->method()) {
  2883         max_level = MAX2(max_level, cur->comp_level());
  2885       cur = cur->osr_link();
  2887     m->set_highest_osr_comp_level(max_level);
  2889   // Remember to unlock again
  2890   OsrList_lock->unlock();
  2893 nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const {
  2894   // This is a short non-blocking critical region, so the no safepoint check is ok.
  2895   OsrList_lock->lock_without_safepoint_check();
  2896   nmethod* osr = osr_nmethods_head();
  2897   nmethod* best = NULL;
  2898   while (osr != NULL) {
  2899     assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
  2900     // There can be a time when a c1 osr method exists but we are waiting
  2901     // for a c2 version. When c2 completes its osr nmethod we will trash
  2902     // the c1 version and only be able to find the c2 version. However
  2903     // while we overflow in the c1 code at back branches we don't want to
  2904     // try and switch to the same code as we are already running
  2906     if (osr->method() == m &&
  2907         (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) {
  2908       if (match_level) {
  2909         if (osr->comp_level() == comp_level) {
  2910           // Found a match - return it.
  2911           OsrList_lock->unlock();
  2912           return osr;
  2914       } else {
  2915         if (best == NULL || (osr->comp_level() > best->comp_level())) {
  2916           if (osr->comp_level() == CompLevel_highest_tier) {
  2917             // Found the best possible - return it.
  2918             OsrList_lock->unlock();
  2919             return osr;
  2921           best = osr;
  2925     osr = osr->osr_link();
  2927   OsrList_lock->unlock();
  2928   if (best != NULL && best->comp_level() >= comp_level && match_level == false) {
  2929     return best;
  2931   return NULL;
  2934 void InstanceKlass::add_member_name(int index, Handle mem_name) {
  2935   jweak mem_name_wref = JNIHandles::make_weak_global(mem_name);
  2936   MutexLocker ml(MemberNameTable_lock);
  2937   assert(0 <= index && index < idnum_allocated_count(), "index is out of bounds");
  2938   DEBUG_ONLY(No_Safepoint_Verifier nsv);
  2940   if (_member_names == NULL) {
  2941     _member_names = new (ResourceObj::C_HEAP, mtClass) MemberNameTable(idnum_allocated_count());
  2943   _member_names->add_member_name(index, mem_name_wref);
  2946 oop InstanceKlass::get_member_name(int index) {
  2947   MutexLocker ml(MemberNameTable_lock);
  2948   assert(0 <= index && index < idnum_allocated_count(), "index is out of bounds");
  2949   DEBUG_ONLY(No_Safepoint_Verifier nsv);
  2951   if (_member_names == NULL) {
  2952     return NULL;
  2954   oop mem_name =_member_names->get_member_name(index);
  2955   return mem_name;
  2958 // -----------------------------------------------------------------------------------------------------
  2959 // Printing
  2961 #ifndef PRODUCT
  2963 #define BULLET  " - "
  2965 static const char* state_names[] = {
  2966   "allocated", "loaded", "linked", "being_initialized", "fully_initialized", "initialization_error"
  2967 };
  2969 static void print_vtable(intptr_t* start, int len, outputStream* st) {
  2970   for (int i = 0; i < len; i++) {
  2971     intptr_t e = start[i];
  2972     st->print("%d : " INTPTR_FORMAT, i, e);
  2973     if (e != 0 && ((Metadata*)e)->is_metaspace_object()) {
  2974       st->print(" ");
  2975       ((Metadata*)e)->print_value_on(st);
  2977     st->cr();
  2981 void InstanceKlass::print_on(outputStream* st) const {
  2982   assert(is_klass(), "must be klass");
  2983   Klass::print_on(st);
  2985   st->print(BULLET"instance size:     %d", size_helper());                        st->cr();
  2986   st->print(BULLET"klass size:        %d", size());                               st->cr();
  2987   st->print(BULLET"access:            "); access_flags().print_on(st);            st->cr();
  2988   st->print(BULLET"state:             "); st->print_cr("%s", state_names[_init_state]);
  2989   st->print(BULLET"name:              "); name()->print_value_on(st);             st->cr();
  2990   st->print(BULLET"super:             "); super()->print_value_on_maybe_null(st); st->cr();
  2991   st->print(BULLET"sub:               ");
  2992   Klass* sub = subklass();
  2993   int n;
  2994   for (n = 0; sub != NULL; n++, sub = sub->next_sibling()) {
  2995     if (n < MaxSubklassPrintSize) {
  2996       sub->print_value_on(st);
  2997       st->print("   ");
  3000   if (n >= MaxSubklassPrintSize) st->print("(%d more klasses...)", n - MaxSubklassPrintSize);
  3001   st->cr();
  3003   if (is_interface()) {
  3004     st->print_cr(BULLET"nof implementors:  %d", nof_implementors());
  3005     if (nof_implementors() == 1) {
  3006       st->print_cr(BULLET"implementor:    ");
  3007       st->print("   ");
  3008       implementor()->print_value_on(st);
  3009       st->cr();
  3013   st->print(BULLET"arrays:            "); array_klasses()->print_value_on_maybe_null(st); st->cr();
  3014   st->print(BULLET"methods:           "); methods()->print_value_on(st);                  st->cr();
  3015   if (Verbose || WizardMode) {
  3016     Array<Method*>* method_array = methods();
  3017     for (int i = 0; i < method_array->length(); i++) {
  3018       st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
  3021   st->print(BULLET"method ordering:   "); method_ordering()->print_value_on(st);      st->cr();
  3022   st->print(BULLET"default_methods:   "); default_methods()->print_value_on(st);      st->cr();
  3023   if (Verbose && default_methods() != NULL) {
  3024     Array<Method*>* method_array = default_methods();
  3025     for (int i = 0; i < method_array->length(); i++) {
  3026       st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
  3029   if (default_vtable_indices() != NULL) {
  3030     st->print(BULLET"default vtable indices:   "); default_vtable_indices()->print_value_on(st);       st->cr();
  3032   st->print(BULLET"local interfaces:  "); local_interfaces()->print_value_on(st);      st->cr();
  3033   st->print(BULLET"trans. interfaces: "); transitive_interfaces()->print_value_on(st); st->cr();
  3034   st->print(BULLET"constants:         "); constants()->print_value_on(st);         st->cr();
  3035   if (class_loader_data() != NULL) {
  3036     st->print(BULLET"class loader data:  ");
  3037     class_loader_data()->print_value_on(st);
  3038     st->cr();
  3040   st->print(BULLET"host class:        "); host_klass()->print_value_on_maybe_null(st); st->cr();
  3041   if (source_file_name() != NULL) {
  3042     st->print(BULLET"source file:       ");
  3043     source_file_name()->print_value_on(st);
  3044     st->cr();
  3046   if (source_debug_extension() != NULL) {
  3047     st->print(BULLET"source debug extension:       ");
  3048     st->print("%s", source_debug_extension());
  3049     st->cr();
  3051   st->print(BULLET"class annotations:       "); class_annotations()->print_value_on(st); st->cr();
  3052   st->print(BULLET"class type annotations:  "); class_type_annotations()->print_value_on(st); st->cr();
  3053   st->print(BULLET"field annotations:       "); fields_annotations()->print_value_on(st); st->cr();
  3054   st->print(BULLET"field type annotations:  "); fields_type_annotations()->print_value_on(st); st->cr();
  3056     bool have_pv = false;
  3057     PreviousVersionWalker pvw(Thread::current(), (InstanceKlass*)this);
  3058     for (PreviousVersionNode * pv_node = pvw.next_previous_version();
  3059          pv_node != NULL; pv_node = pvw.next_previous_version()) {
  3060       if (!have_pv)
  3061         st->print(BULLET"previous version:  ");
  3062       have_pv = true;
  3063       pv_node->prev_constant_pool()->print_value_on(st);
  3065     if (have_pv) st->cr();
  3066   } // pvw is cleaned up
  3068   if (generic_signature() != NULL) {
  3069     st->print(BULLET"generic signature: ");
  3070     generic_signature()->print_value_on(st);
  3071     st->cr();
  3073   st->print(BULLET"inner classes:     "); inner_classes()->print_value_on(st);     st->cr();
  3074   st->print(BULLET"java mirror:       "); java_mirror()->print_value_on(st);       st->cr();
  3075   st->print(BULLET"vtable length      %d  (start addr: " INTPTR_FORMAT ")", vtable_length(), start_of_vtable());  st->cr();
  3076   if (vtable_length() > 0 && (Verbose || WizardMode))  print_vtable(start_of_vtable(), vtable_length(), st);
  3077   st->print(BULLET"itable length      %d (start addr: " INTPTR_FORMAT ")", itable_length(), start_of_itable()); st->cr();
  3078   if (itable_length() > 0 && (Verbose || WizardMode))  print_vtable(start_of_itable(), itable_length(), st);
  3079   st->print_cr(BULLET"---- static fields (%d words):", static_field_size());
  3080   FieldPrinter print_static_field(st);
  3081   ((InstanceKlass*)this)->do_local_static_fields(&print_static_field);
  3082   st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size());
  3083   FieldPrinter print_nonstatic_field(st);
  3084   ((InstanceKlass*)this)->do_nonstatic_fields(&print_nonstatic_field);
  3086   st->print(BULLET"non-static oop maps: ");
  3087   OopMapBlock* map     = start_of_nonstatic_oop_maps();
  3088   OopMapBlock* end_map = map + nonstatic_oop_map_count();
  3089   while (map < end_map) {
  3090     st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1));
  3091     map++;
  3093   st->cr();
  3096 #endif //PRODUCT
  3098 void InstanceKlass::print_value_on(outputStream* st) const {
  3099   assert(is_klass(), "must be klass");
  3100   if (Verbose || WizardMode)  access_flags().print_on(st);
  3101   name()->print_value_on(st);
  3104 #ifndef PRODUCT
  3106 void FieldPrinter::do_field(fieldDescriptor* fd) {
  3107   _st->print(BULLET);
  3108    if (_obj == NULL) {
  3109      fd->print_on(_st);
  3110      _st->cr();
  3111    } else {
  3112      fd->print_on_for(_st, _obj);
  3113      _st->cr();
  3118 void InstanceKlass::oop_print_on(oop obj, outputStream* st) {
  3119   Klass::oop_print_on(obj, st);
  3121   if (this == SystemDictionary::String_klass()) {
  3122     typeArrayOop value  = java_lang_String::value(obj);
  3123     juint        offset = java_lang_String::offset(obj);
  3124     juint        length = java_lang_String::length(obj);
  3125     if (value != NULL &&
  3126         value->is_typeArray() &&
  3127         offset          <= (juint) value->length() &&
  3128         offset + length <= (juint) value->length()) {
  3129       st->print(BULLET"string: ");
  3130       java_lang_String::print(obj, st);
  3131       st->cr();
  3132       if (!WizardMode)  return;  // that is enough
  3136   st->print_cr(BULLET"---- fields (total size %d words):", oop_size(obj));
  3137   FieldPrinter print_field(st, obj);
  3138   do_nonstatic_fields(&print_field);
  3140   if (this == SystemDictionary::Class_klass()) {
  3141     st->print(BULLET"signature: ");
  3142     java_lang_Class::print_signature(obj, st);
  3143     st->cr();
  3144     Klass* mirrored_klass = java_lang_Class::as_Klass(obj);
  3145     st->print(BULLET"fake entry for mirror: ");
  3146     mirrored_klass->print_value_on_maybe_null(st);
  3147     st->cr();
  3148     Klass* array_klass = java_lang_Class::array_klass(obj);
  3149     st->print(BULLET"fake entry for array: ");
  3150     array_klass->print_value_on_maybe_null(st);
  3151     st->cr();
  3152     st->print_cr(BULLET"fake entry for oop_size: %d", java_lang_Class::oop_size(obj));
  3153     st->print_cr(BULLET"fake entry for static_oop_field_count: %d", java_lang_Class::static_oop_field_count(obj));
  3154     Klass* real_klass = java_lang_Class::as_Klass(obj);
  3155     if (real_klass != NULL && real_klass->oop_is_instance()) {
  3156       InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field);
  3158   } else if (this == SystemDictionary::MethodType_klass()) {
  3159     st->print(BULLET"signature: ");
  3160     java_lang_invoke_MethodType::print_signature(obj, st);
  3161     st->cr();
  3165 #endif //PRODUCT
  3167 void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) {
  3168   st->print("a ");
  3169   name()->print_value_on(st);
  3170   obj->print_address_on(st);
  3171   if (this == SystemDictionary::String_klass()
  3172       && java_lang_String::value(obj) != NULL) {
  3173     ResourceMark rm;
  3174     int len = java_lang_String::length(obj);
  3175     int plen = (len < 24 ? len : 12);
  3176     char* str = java_lang_String::as_utf8_string(obj, 0, plen);
  3177     st->print(" = \"%s\"", str);
  3178     if (len > plen)
  3179       st->print("...[%d]", len);
  3180   } else if (this == SystemDictionary::Class_klass()) {
  3181     Klass* k = java_lang_Class::as_Klass(obj);
  3182     st->print(" = ");
  3183     if (k != NULL) {
  3184       k->print_value_on(st);
  3185     } else {
  3186       const char* tname = type2name(java_lang_Class::primitive_type(obj));
  3187       st->print("%s", tname ? tname : "type?");
  3189   } else if (this == SystemDictionary::MethodType_klass()) {
  3190     st->print(" = ");
  3191     java_lang_invoke_MethodType::print_signature(obj, st);
  3192   } else if (java_lang_boxing_object::is_instance(obj)) {
  3193     st->print(" = ");
  3194     java_lang_boxing_object::print(obj, st);
  3195   } else if (this == SystemDictionary::LambdaForm_klass()) {
  3196     oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj);
  3197     if (vmentry != NULL) {
  3198       st->print(" => ");
  3199       vmentry->print_value_on(st);
  3201   } else if (this == SystemDictionary::MemberName_klass()) {
  3202     Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj);
  3203     if (vmtarget != NULL) {
  3204       st->print(" = ");
  3205       vmtarget->print_value_on(st);
  3206     } else {
  3207       java_lang_invoke_MemberName::clazz(obj)->print_value_on(st);
  3208       st->print(".");
  3209       java_lang_invoke_MemberName::name(obj)->print_value_on(st);
  3214 const char* InstanceKlass::internal_name() const {
  3215   return external_name();
  3218 #if INCLUDE_SERVICES
  3219 // Size Statistics
  3220 void InstanceKlass::collect_statistics(KlassSizeStats *sz) const {
  3221   Klass::collect_statistics(sz);
  3223   sz->_inst_size  = HeapWordSize * size_helper();
  3224   sz->_vtab_bytes = HeapWordSize * align_object_offset(vtable_length());
  3225   sz->_itab_bytes = HeapWordSize * align_object_offset(itable_length());
  3226   sz->_nonstatic_oopmap_bytes = HeapWordSize *
  3227         ((is_interface() || is_anonymous()) ?
  3228          align_object_offset(nonstatic_oop_map_size()) :
  3229          nonstatic_oop_map_size());
  3231   int n = 0;
  3232   n += (sz->_methods_array_bytes         = sz->count_array(methods()));
  3233   n += (sz->_method_ordering_bytes       = sz->count_array(method_ordering()));
  3234   n += (sz->_local_interfaces_bytes      = sz->count_array(local_interfaces()));
  3235   n += (sz->_transitive_interfaces_bytes = sz->count_array(transitive_interfaces()));
  3236   n += (sz->_fields_bytes                = sz->count_array(fields()));
  3237   n += (sz->_inner_classes_bytes         = sz->count_array(inner_classes()));
  3238   sz->_ro_bytes += n;
  3240   const ConstantPool* cp = constants();
  3241   if (cp) {
  3242     cp->collect_statistics(sz);
  3245   const Annotations* anno = annotations();
  3246   if (anno) {
  3247     anno->collect_statistics(sz);
  3250   const Array<Method*>* methods_array = methods();
  3251   if (methods()) {
  3252     for (int i = 0; i < methods_array->length(); i++) {
  3253       Method* method = methods_array->at(i);
  3254       if (method) {
  3255         sz->_method_count ++;
  3256         method->collect_statistics(sz);
  3261 #endif // INCLUDE_SERVICES
  3263 // Verification
  3265 class VerifyFieldClosure: public OopClosure {
  3266  protected:
  3267   template <class T> void do_oop_work(T* p) {
  3268     oop obj = oopDesc::load_decode_heap_oop(p);
  3269     if (!obj->is_oop_or_null()) {
  3270       tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p, (address)obj);
  3271       Universe::print();
  3272       guarantee(false, "boom");
  3275  public:
  3276   virtual void do_oop(oop* p)       { VerifyFieldClosure::do_oop_work(p); }
  3277   virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); }
  3278 };
  3280 void InstanceKlass::verify_on(outputStream* st) {
  3281 #ifndef PRODUCT
  3282   // Avoid redundant verifies, this really should be in product.
  3283   if (_verify_count == Universe::verify_count()) return;
  3284   _verify_count = Universe::verify_count();
  3285 #endif
  3287   // Verify Klass
  3288   Klass::verify_on(st);
  3290   // Verify that klass is present in ClassLoaderData
  3291   guarantee(class_loader_data()->contains_klass(this),
  3292             "this class isn't found in class loader data");
  3294   // Verify vtables
  3295   if (is_linked()) {
  3296     ResourceMark rm;
  3297     // $$$ This used to be done only for m/s collections.  Doing it
  3298     // always seemed a valid generalization.  (DLD -- 6/00)
  3299     vtable()->verify(st);
  3302   // Verify first subklass
  3303   if (subklass_oop() != NULL) {
  3304     guarantee(subklass_oop()->is_klass(), "should be klass");
  3307   // Verify siblings
  3308   Klass* super = this->super();
  3309   Klass* sib = next_sibling();
  3310   if (sib != NULL) {
  3311     if (sib == this) {
  3312       fatal(err_msg("subclass points to itself " PTR_FORMAT, sib));
  3315     guarantee(sib->is_klass(), "should be klass");
  3316     guarantee(sib->super() == super, "siblings should have same superklass");
  3319   // Verify implementor fields
  3320   Klass* im = implementor();
  3321   if (im != NULL) {
  3322     guarantee(is_interface(), "only interfaces should have implementor set");
  3323     guarantee(im->is_klass(), "should be klass");
  3324     guarantee(!im->is_interface() || im == this,
  3325       "implementors cannot be interfaces");
  3328   // Verify local interfaces
  3329   if (local_interfaces()) {
  3330     Array<Klass*>* local_interfaces = this->local_interfaces();
  3331     for (int j = 0; j < local_interfaces->length(); j++) {
  3332       Klass* e = local_interfaces->at(j);
  3333       guarantee(e->is_klass() && e->is_interface(), "invalid local interface");
  3337   // Verify transitive interfaces
  3338   if (transitive_interfaces() != NULL) {
  3339     Array<Klass*>* transitive_interfaces = this->transitive_interfaces();
  3340     for (int j = 0; j < transitive_interfaces->length(); j++) {
  3341       Klass* e = transitive_interfaces->at(j);
  3342       guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface");
  3346   // Verify methods
  3347   if (methods() != NULL) {
  3348     Array<Method*>* methods = this->methods();
  3349     for (int j = 0; j < methods->length(); j++) {
  3350       guarantee(methods->at(j)->is_method(), "non-method in methods array");
  3352     for (int j = 0; j < methods->length() - 1; j++) {
  3353       Method* m1 = methods->at(j);
  3354       Method* m2 = methods->at(j + 1);
  3355       guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
  3359   // Verify method ordering
  3360   if (method_ordering() != NULL) {
  3361     Array<int>* method_ordering = this->method_ordering();
  3362     int length = method_ordering->length();
  3363     if (JvmtiExport::can_maintain_original_method_order() ||
  3364         ((UseSharedSpaces || DumpSharedSpaces) && length != 0)) {
  3365       guarantee(length == methods()->length(), "invalid method ordering length");
  3366       jlong sum = 0;
  3367       for (int j = 0; j < length; j++) {
  3368         int original_index = method_ordering->at(j);
  3369         guarantee(original_index >= 0, "invalid method ordering index");
  3370         guarantee(original_index < length, "invalid method ordering index");
  3371         sum += original_index;
  3373       // Verify sum of indices 0,1,...,length-1
  3374       guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum");
  3375     } else {
  3376       guarantee(length == 0, "invalid method ordering length");
  3380   // Verify default methods
  3381   if (default_methods() != NULL) {
  3382     Array<Method*>* methods = this->default_methods();
  3383     for (int j = 0; j < methods->length(); j++) {
  3384       guarantee(methods->at(j)->is_method(), "non-method in methods array");
  3386     for (int j = 0; j < methods->length() - 1; j++) {
  3387       Method* m1 = methods->at(j);
  3388       Method* m2 = methods->at(j + 1);
  3389       guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
  3393   // Verify JNI static field identifiers
  3394   if (jni_ids() != NULL) {
  3395     jni_ids()->verify(this);
  3398   // Verify other fields
  3399   if (array_klasses() != NULL) {
  3400     guarantee(array_klasses()->is_klass(), "should be klass");
  3402   if (constants() != NULL) {
  3403     guarantee(constants()->is_constantPool(), "should be constant pool");
  3405   const Klass* host = host_klass();
  3406   if (host != NULL) {
  3407     guarantee(host->is_klass(), "should be klass");
  3411 void InstanceKlass::oop_verify_on(oop obj, outputStream* st) {
  3412   Klass::oop_verify_on(obj, st);
  3413   VerifyFieldClosure blk;
  3414   obj->oop_iterate_no_header(&blk);
  3418 // JNIid class for jfieldIDs only
  3419 // Note to reviewers:
  3420 // These JNI functions are just moved over to column 1 and not changed
  3421 // in the compressed oops workspace.
  3422 JNIid::JNIid(Klass* holder, int offset, JNIid* next) {
  3423   _holder = holder;
  3424   _offset = offset;
  3425   _next = next;
  3426   debug_only(_is_static_field_id = false;)
  3430 JNIid* JNIid::find(int offset) {
  3431   JNIid* current = this;
  3432   while (current != NULL) {
  3433     if (current->offset() == offset) return current;
  3434     current = current->next();
  3436   return NULL;
  3439 void JNIid::deallocate(JNIid* current) {
  3440   while (current != NULL) {
  3441     JNIid* next = current->next();
  3442     delete current;
  3443     current = next;
  3448 void JNIid::verify(Klass* holder) {
  3449   int first_field_offset  = InstanceMirrorKlass::offset_of_static_fields();
  3450   int end_field_offset;
  3451   end_field_offset = first_field_offset + (InstanceKlass::cast(holder)->static_field_size() * wordSize);
  3453   JNIid* current = this;
  3454   while (current != NULL) {
  3455     guarantee(current->holder() == holder, "Invalid klass in JNIid");
  3456 #ifdef ASSERT
  3457     int o = current->offset();
  3458     if (current->is_static_field_id()) {
  3459       guarantee(o >= first_field_offset  && o < end_field_offset,  "Invalid static field offset in JNIid");
  3461 #endif
  3462     current = current->next();
  3467 #ifdef ASSERT
  3468 void InstanceKlass::set_init_state(ClassState state) {
  3469   bool good_state = is_shared() ? (_init_state <= state)
  3470                                                : (_init_state < state);
  3471   assert(good_state || state == allocated, "illegal state transition");
  3472   _init_state = (u1)state;
  3474 #endif
  3477 // RedefineClasses() support for previous versions:
  3479 // Purge previous versions
  3480 static void purge_previous_versions_internal(InstanceKlass* ik, int emcp_method_count) {
  3481   if (ik->previous_versions() != NULL) {
  3482     // This klass has previous versions so see what we can cleanup
  3483     // while it is safe to do so.
  3485     int deleted_count = 0;    // leave debugging breadcrumbs
  3486     int live_count = 0;
  3487     ClassLoaderData* loader_data = ik->class_loader_data() == NULL ?
  3488                        ClassLoaderData::the_null_class_loader_data() :
  3489                        ik->class_loader_data();
  3491     // RC_TRACE macro has an embedded ResourceMark
  3492     RC_TRACE(0x00000200, ("purge: %s: previous version length=%d",
  3493       ik->external_name(), ik->previous_versions()->length()));
  3495     for (int i = ik->previous_versions()->length() - 1; i >= 0; i--) {
  3496       // check the previous versions array
  3497       PreviousVersionNode * pv_node = ik->previous_versions()->at(i);
  3498       ConstantPool* cp_ref = pv_node->prev_constant_pool();
  3499       assert(cp_ref != NULL, "cp ref was unexpectedly cleared");
  3501       ConstantPool* pvcp = cp_ref;
  3502       if (!pvcp->on_stack()) {
  3503         // If the constant pool isn't on stack, none of the methods
  3504         // are executing.  Delete all the methods, the constant pool and
  3505         // and this previous version node.
  3506         GrowableArray<Method*>* method_refs = pv_node->prev_EMCP_methods();
  3507         if (method_refs != NULL) {
  3508           for (int j = method_refs->length() - 1; j >= 0; j--) {
  3509             Method* method = method_refs->at(j);
  3510             assert(method != NULL, "method ref was unexpectedly cleared");
  3511             method_refs->remove_at(j);
  3512             // method will be freed with associated class.
  3515         // Remove the constant pool
  3516         delete pv_node;
  3517         // Since we are traversing the array backwards, we don't have to
  3518         // do anything special with the index.
  3519         ik->previous_versions()->remove_at(i);
  3520         deleted_count++;
  3521         continue;
  3522       } else {
  3523         RC_TRACE(0x00000200, ("purge: previous version @%d is alive", i));
  3524         assert(pvcp->pool_holder() != NULL, "Constant pool with no holder");
  3525         guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack");
  3526         live_count++;
  3529       // At least one method is live in this previous version, clean out
  3530       // the others or mark them as obsolete.
  3531       GrowableArray<Method*>* method_refs = pv_node->prev_EMCP_methods();
  3532       if (method_refs != NULL) {
  3533         RC_TRACE(0x00000200, ("purge: previous methods length=%d",
  3534           method_refs->length()));
  3535         for (int j = method_refs->length() - 1; j >= 0; j--) {
  3536           Method* method = method_refs->at(j);
  3537           assert(method != NULL, "method ref was unexpectedly cleared");
  3539           // Remove the emcp method if it's not executing
  3540           // If it's been made obsolete by a redefinition of a non-emcp
  3541           // method, mark it as obsolete but leave it to clean up later.
  3542           if (!method->on_stack()) {
  3543             method_refs->remove_at(j);
  3544           } else if (emcp_method_count == 0) {
  3545             method->set_is_obsolete();
  3546           } else {
  3547             // RC_TRACE macro has an embedded ResourceMark
  3548             RC_TRACE(0x00000200,
  3549               ("purge: %s(%s): prev method @%d in version @%d is alive",
  3550               method->name()->as_C_string(),
  3551               method->signature()->as_C_string(), j, i));
  3556     assert(ik->previous_versions()->length() == live_count, "sanity check");
  3557     RC_TRACE(0x00000200,
  3558       ("purge: previous version stats: live=%d, deleted=%d", live_count,
  3559       deleted_count));
  3563 // External interface for use during class unloading.
  3564 void InstanceKlass::purge_previous_versions(InstanceKlass* ik) {
  3565   // Call with >0 emcp methods since they are not currently being redefined.
  3566   purge_previous_versions_internal(ik, 1);
  3570 // Potentially add an information node that contains pointers to the
  3571 // interesting parts of the previous version of the_class.
  3572 // This is also where we clean out any unused references.
  3573 // Note that while we delete nodes from the _previous_versions
  3574 // array, we never delete the array itself until the klass is
  3575 // unloaded. The has_been_redefined() query depends on that fact.
  3576 //
  3577 void InstanceKlass::add_previous_version(instanceKlassHandle ikh,
  3578        BitMap* emcp_methods, int emcp_method_count) {
  3579   assert(Thread::current()->is_VM_thread(),
  3580          "only VMThread can add previous versions");
  3582   if (_previous_versions == NULL) {
  3583     // This is the first previous version so make some space.
  3584     // Start with 2 elements under the assumption that the class
  3585     // won't be redefined much.
  3586     _previous_versions =  new (ResourceObj::C_HEAP, mtClass)
  3587                             GrowableArray<PreviousVersionNode *>(2, true);
  3590   ConstantPool* cp_ref = ikh->constants();
  3592   // RC_TRACE macro has an embedded ResourceMark
  3593   RC_TRACE(0x00000400, ("adding previous version ref for %s @%d, EMCP_cnt=%d "
  3594                         "on_stack=%d",
  3595     ikh->external_name(), _previous_versions->length(), emcp_method_count,
  3596     cp_ref->on_stack()));
  3598   // If the constant pool for this previous version of the class
  3599   // is not marked as being on the stack, then none of the methods
  3600   // in this previous version of the class are on the stack so
  3601   // we don't need to create a new PreviousVersionNode. However,
  3602   // we still need to examine older previous versions below.
  3603   Array<Method*>* old_methods = ikh->methods();
  3605   if (cp_ref->on_stack()) {
  3606     PreviousVersionNode * pv_node = NULL;
  3607     if (emcp_method_count == 0) {
  3608       // non-shared ConstantPool gets a reference
  3609       pv_node = new PreviousVersionNode(cp_ref, NULL);
  3610       RC_TRACE(0x00000400,
  3611           ("add: all methods are obsolete; flushing any EMCP refs"));
  3612     } else {
  3613       int local_count = 0;
  3614       GrowableArray<Method*>* method_refs = new (ResourceObj::C_HEAP, mtClass)
  3615           GrowableArray<Method*>(emcp_method_count, true);
  3616       for (int i = 0; i < old_methods->length(); i++) {
  3617         if (emcp_methods->at(i)) {
  3618             // this old method is EMCP. Save it only if it's on the stack
  3619             Method* old_method = old_methods->at(i);
  3620             if (old_method->on_stack()) {
  3621               method_refs->append(old_method);
  3623           if (++local_count >= emcp_method_count) {
  3624             // no more EMCP methods so bail out now
  3625             break;
  3629       // non-shared ConstantPool gets a reference
  3630       pv_node = new PreviousVersionNode(cp_ref, method_refs);
  3632     // append new previous version.
  3633     _previous_versions->append(pv_node);
  3636   // Since the caller is the VMThread and we are at a safepoint, this
  3637   // is a good time to clear out unused references.
  3639   RC_TRACE(0x00000400, ("add: previous version length=%d",
  3640     _previous_versions->length()));
  3642   // Purge previous versions not executing on the stack
  3643   purge_previous_versions_internal(this, emcp_method_count);
  3645   int obsolete_method_count = old_methods->length() - emcp_method_count;
  3647   if (emcp_method_count != 0 && obsolete_method_count != 0 &&
  3648       _previous_versions->length() > 0) {
  3649     // We have a mix of obsolete and EMCP methods so we have to
  3650     // clear out any matching EMCP method entries the hard way.
  3651     int local_count = 0;
  3652     for (int i = 0; i < old_methods->length(); i++) {
  3653       if (!emcp_methods->at(i)) {
  3654         // only obsolete methods are interesting
  3655         Method* old_method = old_methods->at(i);
  3656         Symbol* m_name = old_method->name();
  3657         Symbol* m_signature = old_method->signature();
  3659         // we might not have added the last entry
  3660         for (int j = _previous_versions->length() - 1; j >= 0; j--) {
  3661           // check the previous versions array for non executing obsolete methods
  3662           PreviousVersionNode * pv_node = _previous_versions->at(j);
  3664           GrowableArray<Method*>* method_refs = pv_node->prev_EMCP_methods();
  3665           if (method_refs == NULL) {
  3666             // We have run into a PreviousVersion generation where
  3667             // all methods were made obsolete during that generation's
  3668             // RedefineClasses() operation. At the time of that
  3669             // operation, all EMCP methods were flushed so we don't
  3670             // have to go back any further.
  3671             //
  3672             // A NULL method_refs is different than an empty method_refs.
  3673             // We cannot infer any optimizations about older generations
  3674             // from an empty method_refs for the current generation.
  3675             break;
  3678           for (int k = method_refs->length() - 1; k >= 0; k--) {
  3679             Method* method = method_refs->at(k);
  3681             if (!method->is_obsolete() &&
  3682                 method->name() == m_name &&
  3683                 method->signature() == m_signature) {
  3684               // The current RedefineClasses() call has made all EMCP
  3685               // versions of this method obsolete so mark it as obsolete
  3686               // and remove the reference.
  3687               RC_TRACE(0x00000400,
  3688                 ("add: %s(%s): flush obsolete method @%d in version @%d",
  3689                 m_name->as_C_string(), m_signature->as_C_string(), k, j));
  3691               method->set_is_obsolete();
  3692               // Leave obsolete methods on the previous version list to
  3693               // clean up later.
  3694               break;
  3698           // The previous loop may not find a matching EMCP method, but
  3699           // that doesn't mean that we can optimize and not go any
  3700           // further back in the PreviousVersion generations. The EMCP
  3701           // method for this generation could have already been deleted,
  3702           // but there still may be an older EMCP method that has not
  3703           // been deleted.
  3706         if (++local_count >= obsolete_method_count) {
  3707           // no more obsolete methods so bail out now
  3708           break;
  3713 } // end add_previous_version()
  3716 // Determine if InstanceKlass has a previous version.
  3717 bool InstanceKlass::has_previous_version() const {
  3718   return (_previous_versions != NULL && _previous_versions->length() > 0);
  3719 } // end has_previous_version()
  3722 Method* InstanceKlass::method_with_idnum(int idnum) {
  3723   Method* m = NULL;
  3724   if (idnum < methods()->length()) {
  3725     m = methods()->at(idnum);
  3727   if (m == NULL || m->method_idnum() != idnum) {
  3728     for (int index = 0; index < methods()->length(); ++index) {
  3729       m = methods()->at(index);
  3730       if (m->method_idnum() == idnum) {
  3731         return m;
  3734     // None found, return null for the caller to handle.
  3735     return NULL;
  3737   return m;
  3740 jint InstanceKlass::get_cached_class_file_len() {
  3741   return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file);
  3744 unsigned char * InstanceKlass::get_cached_class_file_bytes() {
  3745   return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file);
  3749 // Construct a PreviousVersionNode entry for the array hung off
  3750 // the InstanceKlass.
  3751 PreviousVersionNode::PreviousVersionNode(ConstantPool* prev_constant_pool,
  3752   GrowableArray<Method*>* prev_EMCP_methods) {
  3754   _prev_constant_pool = prev_constant_pool;
  3755   _prev_EMCP_methods = prev_EMCP_methods;
  3759 // Destroy a PreviousVersionNode
  3760 PreviousVersionNode::~PreviousVersionNode() {
  3761   if (_prev_constant_pool != NULL) {
  3762     _prev_constant_pool = NULL;
  3765   if (_prev_EMCP_methods != NULL) {
  3766     delete _prev_EMCP_methods;
  3770 // Construct a helper for walking the previous versions array
  3771 PreviousVersionWalker::PreviousVersionWalker(Thread* thread, InstanceKlass *ik) {
  3772   _thread = thread;
  3773   _previous_versions = ik->previous_versions();
  3774   _current_index = 0;
  3775   _current_p = NULL;
  3776   _current_constant_pool_handle = constantPoolHandle(thread, ik->constants());
  3780 // Return the interesting information for the next previous version
  3781 // of the klass. Returns NULL if there are no more previous versions.
  3782 PreviousVersionNode* PreviousVersionWalker::next_previous_version() {
  3783   if (_previous_versions == NULL) {
  3784     // no previous versions so nothing to return
  3785     return NULL;
  3788   _current_p = NULL;  // reset to NULL
  3789   _current_constant_pool_handle = NULL;
  3791   int length = _previous_versions->length();
  3793   while (_current_index < length) {
  3794     PreviousVersionNode * pv_node = _previous_versions->at(_current_index++);
  3796     // Save a handle to the constant pool for this previous version,
  3797     // which keeps all the methods from being deallocated.
  3798     _current_constant_pool_handle = constantPoolHandle(_thread, pv_node->prev_constant_pool());
  3799     _current_p = pv_node;
  3800     return pv_node;
  3803   return NULL;
  3804 } // end next_previous_version()

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