src/share/vm/memory/universe.cpp

Tue, 16 Feb 2016 21:42:29 +0000

author
poonam
date
Tue, 16 Feb 2016 21:42:29 +0000
changeset 8308
6acf14e730dd
parent 8213
88ae10297731
child 8604
04d83ba48607
child 9301
d47844b56aaf
permissions
-rw-r--r--

8072725: Provide more granular levels for GC verification
Summary: Add option VerifySubSet to selectively verify the memory sub-systems
Reviewed-by: kevinw, jmasa

     1 /*
     2  * Copyright (c) 1997, 2016, 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/classLoader.hpp"
    27 #include "classfile/classLoaderData.hpp"
    28 #include "classfile/javaClasses.hpp"
    29 #if INCLUDE_CDS
    30 #include "classfile/sharedClassUtil.hpp"
    31 #endif
    32 #include "classfile/symbolTable.hpp"
    33 #include "classfile/systemDictionary.hpp"
    34 #include "classfile/vmSymbols.hpp"
    35 #include "code/codeCache.hpp"
    36 #include "code/dependencies.hpp"
    37 #include "gc_interface/collectedHeap.inline.hpp"
    38 #include "interpreter/interpreter.hpp"
    39 #include "memory/cardTableModRefBS.hpp"
    40 #include "memory/filemap.hpp"
    41 #include "memory/gcLocker.inline.hpp"
    42 #include "memory/genCollectedHeap.hpp"
    43 #include "memory/genRemSet.hpp"
    44 #include "memory/generation.hpp"
    45 #include "memory/metadataFactory.hpp"
    46 #include "memory/metaspaceShared.hpp"
    47 #include "memory/oopFactory.hpp"
    48 #include "memory/space.hpp"
    49 #include "memory/universe.hpp"
    50 #include "memory/universe.inline.hpp"
    51 #include "oops/constantPool.hpp"
    52 #include "oops/instanceClassLoaderKlass.hpp"
    53 #include "oops/instanceKlass.hpp"
    54 #include "oops/instanceMirrorKlass.hpp"
    55 #include "oops/instanceRefKlass.hpp"
    56 #include "oops/oop.inline.hpp"
    57 #include "oops/typeArrayKlass.hpp"
    58 #include "prims/jvmtiRedefineClassesTrace.hpp"
    59 #include "runtime/arguments.hpp"
    60 #include "runtime/deoptimization.hpp"
    61 #include "runtime/fprofiler.hpp"
    62 #include "runtime/handles.inline.hpp"
    63 #include "runtime/init.hpp"
    64 #include "runtime/java.hpp"
    65 #include "runtime/javaCalls.hpp"
    66 #include "runtime/sharedRuntime.hpp"
    67 #include "runtime/synchronizer.hpp"
    68 #include "runtime/thread.inline.hpp"
    69 #include "runtime/timer.hpp"
    70 #include "runtime/vm_operations.hpp"
    71 #include "services/memoryService.hpp"
    72 #include "utilities/copy.hpp"
    73 #include "utilities/events.hpp"
    74 #include "utilities/hashtable.inline.hpp"
    75 #include "utilities/preserveException.hpp"
    76 #include "utilities/macros.hpp"
    77 #if INCLUDE_ALL_GCS
    78 #include "gc_implementation/concurrentMarkSweep/cmsAdaptiveSizePolicy.hpp"
    79 #include "gc_implementation/concurrentMarkSweep/cmsCollectorPolicy.hpp"
    80 #include "gc_implementation/g1/g1CollectedHeap.inline.hpp"
    81 #include "gc_implementation/g1/g1CollectorPolicy_ext.hpp"
    82 #include "gc_implementation/parallelScavenge/parallelScavengeHeap.hpp"
    83 #endif // INCLUDE_ALL_GCS
    85 PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC
    87 // Known objects
    88 Klass* Universe::_boolArrayKlassObj                 = NULL;
    89 Klass* Universe::_byteArrayKlassObj                 = NULL;
    90 Klass* Universe::_charArrayKlassObj                 = NULL;
    91 Klass* Universe::_intArrayKlassObj                  = NULL;
    92 Klass* Universe::_shortArrayKlassObj                = NULL;
    93 Klass* Universe::_longArrayKlassObj                 = NULL;
    94 Klass* Universe::_singleArrayKlassObj               = NULL;
    95 Klass* Universe::_doubleArrayKlassObj               = NULL;
    96 Klass* Universe::_typeArrayKlassObjs[T_VOID+1]      = { NULL /*, NULL...*/ };
    97 Klass* Universe::_objectArrayKlassObj               = NULL;
    98 oop Universe::_int_mirror                             = NULL;
    99 oop Universe::_float_mirror                           = NULL;
   100 oop Universe::_double_mirror                          = NULL;
   101 oop Universe::_byte_mirror                            = NULL;
   102 oop Universe::_bool_mirror                            = NULL;
   103 oop Universe::_char_mirror                            = NULL;
   104 oop Universe::_long_mirror                            = NULL;
   105 oop Universe::_short_mirror                           = NULL;
   106 oop Universe::_void_mirror                            = NULL;
   107 oop Universe::_mirrors[T_VOID+1]                      = { NULL /*, NULL...*/ };
   108 oop Universe::_main_thread_group                      = NULL;
   109 oop Universe::_system_thread_group                    = NULL;
   110 objArrayOop Universe::_the_empty_class_klass_array    = NULL;
   111 Array<Klass*>* Universe::_the_array_interfaces_array = NULL;
   112 oop Universe::_the_null_string                        = NULL;
   113 oop Universe::_the_min_jint_string                   = NULL;
   114 LatestMethodCache* Universe::_finalizer_register_cache = NULL;
   115 LatestMethodCache* Universe::_loader_addClass_cache    = NULL;
   116 LatestMethodCache* Universe::_pd_implies_cache         = NULL;
   117 LatestMethodCache* Universe::_throw_illegal_access_error_cache = NULL;
   118 oop Universe::_out_of_memory_error_java_heap          = NULL;
   119 oop Universe::_out_of_memory_error_metaspace          = NULL;
   120 oop Universe::_out_of_memory_error_class_metaspace    = NULL;
   121 oop Universe::_out_of_memory_error_array_size         = NULL;
   122 oop Universe::_out_of_memory_error_gc_overhead_limit  = NULL;
   123 oop Universe::_out_of_memory_error_realloc_objects    = NULL;
   124 objArrayOop Universe::_preallocated_out_of_memory_error_array = NULL;
   125 volatile jint Universe::_preallocated_out_of_memory_error_avail_count = 0;
   126 bool Universe::_verify_in_progress                    = false;
   127 long Universe::verify_flags                           = Universe::Verify_All;
   128 oop Universe::_null_ptr_exception_instance            = NULL;
   129 oop Universe::_arithmetic_exception_instance          = NULL;
   130 oop Universe::_virtual_machine_error_instance         = NULL;
   131 oop Universe::_vm_exception                           = NULL;
   132 oop Universe::_allocation_context_notification_obj    = NULL;
   134 Array<int>* Universe::_the_empty_int_array            = NULL;
   135 Array<u2>* Universe::_the_empty_short_array           = NULL;
   136 Array<Klass*>* Universe::_the_empty_klass_array     = NULL;
   137 Array<Method*>* Universe::_the_empty_method_array   = NULL;
   139 // These variables are guarded by FullGCALot_lock.
   140 debug_only(objArrayOop Universe::_fullgc_alot_dummy_array = NULL;)
   141 debug_only(int Universe::_fullgc_alot_dummy_next      = 0;)
   143 // Heap
   144 int             Universe::_verify_count = 0;
   146 int             Universe::_base_vtable_size = 0;
   147 bool            Universe::_bootstrapping = false;
   148 bool            Universe::_fully_initialized = false;
   150 size_t          Universe::_heap_capacity_at_last_gc;
   151 size_t          Universe::_heap_used_at_last_gc = 0;
   153 CollectedHeap*  Universe::_collectedHeap = NULL;
   155 NarrowPtrStruct Universe::_narrow_oop = { NULL, 0, true };
   156 NarrowPtrStruct Universe::_narrow_klass = { NULL, 0, true };
   157 address Universe::_narrow_ptrs_base;
   159 void Universe::basic_type_classes_do(void f(Klass*)) {
   160   f(boolArrayKlassObj());
   161   f(byteArrayKlassObj());
   162   f(charArrayKlassObj());
   163   f(intArrayKlassObj());
   164   f(shortArrayKlassObj());
   165   f(longArrayKlassObj());
   166   f(singleArrayKlassObj());
   167   f(doubleArrayKlassObj());
   168 }
   170 void Universe::oops_do(OopClosure* f, bool do_all) {
   172   f->do_oop((oop*) &_int_mirror);
   173   f->do_oop((oop*) &_float_mirror);
   174   f->do_oop((oop*) &_double_mirror);
   175   f->do_oop((oop*) &_byte_mirror);
   176   f->do_oop((oop*) &_bool_mirror);
   177   f->do_oop((oop*) &_char_mirror);
   178   f->do_oop((oop*) &_long_mirror);
   179   f->do_oop((oop*) &_short_mirror);
   180   f->do_oop((oop*) &_void_mirror);
   182   for (int i = T_BOOLEAN; i < T_VOID+1; i++) {
   183     f->do_oop((oop*) &_mirrors[i]);
   184   }
   185   assert(_mirrors[0] == NULL && _mirrors[T_BOOLEAN - 1] == NULL, "checking");
   187   f->do_oop((oop*)&_the_empty_class_klass_array);
   188   f->do_oop((oop*)&_the_null_string);
   189   f->do_oop((oop*)&_the_min_jint_string);
   190   f->do_oop((oop*)&_out_of_memory_error_java_heap);
   191   f->do_oop((oop*)&_out_of_memory_error_metaspace);
   192   f->do_oop((oop*)&_out_of_memory_error_class_metaspace);
   193   f->do_oop((oop*)&_out_of_memory_error_array_size);
   194   f->do_oop((oop*)&_out_of_memory_error_gc_overhead_limit);
   195   f->do_oop((oop*)&_out_of_memory_error_realloc_objects);
   196     f->do_oop((oop*)&_preallocated_out_of_memory_error_array);
   197   f->do_oop((oop*)&_null_ptr_exception_instance);
   198   f->do_oop((oop*)&_arithmetic_exception_instance);
   199   f->do_oop((oop*)&_virtual_machine_error_instance);
   200   f->do_oop((oop*)&_main_thread_group);
   201   f->do_oop((oop*)&_system_thread_group);
   202   f->do_oop((oop*)&_vm_exception);
   203   f->do_oop((oop*)&_allocation_context_notification_obj);
   204   debug_only(f->do_oop((oop*)&_fullgc_alot_dummy_array);)
   205 }
   207 // Serialize metadata in and out of CDS archive, not oops.
   208 void Universe::serialize(SerializeClosure* f, bool do_all) {
   210   f->do_ptr((void**)&_boolArrayKlassObj);
   211   f->do_ptr((void**)&_byteArrayKlassObj);
   212   f->do_ptr((void**)&_charArrayKlassObj);
   213   f->do_ptr((void**)&_intArrayKlassObj);
   214   f->do_ptr((void**)&_shortArrayKlassObj);
   215   f->do_ptr((void**)&_longArrayKlassObj);
   216   f->do_ptr((void**)&_singleArrayKlassObj);
   217   f->do_ptr((void**)&_doubleArrayKlassObj);
   218   f->do_ptr((void**)&_objectArrayKlassObj);
   220   {
   221     for (int i = 0; i < T_VOID+1; i++) {
   222       if (_typeArrayKlassObjs[i] != NULL) {
   223         assert(i >= T_BOOLEAN, "checking");
   224         f->do_ptr((void**)&_typeArrayKlassObjs[i]);
   225       } else if (do_all) {
   226         f->do_ptr((void**)&_typeArrayKlassObjs[i]);
   227       }
   228     }
   229   }
   231   f->do_ptr((void**)&_the_array_interfaces_array);
   232   f->do_ptr((void**)&_the_empty_int_array);
   233   f->do_ptr((void**)&_the_empty_short_array);
   234   f->do_ptr((void**)&_the_empty_method_array);
   235   f->do_ptr((void**)&_the_empty_klass_array);
   236   _finalizer_register_cache->serialize(f);
   237   _loader_addClass_cache->serialize(f);
   238   _pd_implies_cache->serialize(f);
   239   _throw_illegal_access_error_cache->serialize(f);
   240 }
   242 void Universe::check_alignment(uintx size, uintx alignment, const char* name) {
   243   if (size < alignment || size % alignment != 0) {
   244     vm_exit_during_initialization(
   245       err_msg("Size of %s (" UINTX_FORMAT " bytes) must be aligned to " UINTX_FORMAT " bytes", name, size, alignment));
   246   }
   247 }
   249 void initialize_basic_type_klass(Klass* k, TRAPS) {
   250   Klass* ok = SystemDictionary::Object_klass();
   251   if (UseSharedSpaces) {
   252     ClassLoaderData* loader_data = ClassLoaderData::the_null_class_loader_data();
   253     assert(k->super() == ok, "u3");
   254     k->restore_unshareable_info(loader_data, Handle(), CHECK);
   255   } else {
   256     k->initialize_supers(ok, CHECK);
   257   }
   258   k->append_to_sibling_list();
   259 }
   261 void Universe::genesis(TRAPS) {
   262   ResourceMark rm;
   264   { FlagSetting fs(_bootstrapping, true);
   266     { MutexLocker mc(Compile_lock);
   268       // determine base vtable size; without that we cannot create the array klasses
   269       compute_base_vtable_size();
   271       if (!UseSharedSpaces) {
   272         _boolArrayKlassObj      = TypeArrayKlass::create_klass(T_BOOLEAN, sizeof(jboolean), CHECK);
   273         _charArrayKlassObj      = TypeArrayKlass::create_klass(T_CHAR,    sizeof(jchar),    CHECK);
   274         _singleArrayKlassObj    = TypeArrayKlass::create_klass(T_FLOAT,   sizeof(jfloat),   CHECK);
   275         _doubleArrayKlassObj    = TypeArrayKlass::create_klass(T_DOUBLE,  sizeof(jdouble),  CHECK);
   276         _byteArrayKlassObj      = TypeArrayKlass::create_klass(T_BYTE,    sizeof(jbyte),    CHECK);
   277         _shortArrayKlassObj     = TypeArrayKlass::create_klass(T_SHORT,   sizeof(jshort),   CHECK);
   278         _intArrayKlassObj       = TypeArrayKlass::create_klass(T_INT,     sizeof(jint),     CHECK);
   279         _longArrayKlassObj      = TypeArrayKlass::create_klass(T_LONG,    sizeof(jlong),    CHECK);
   281         _typeArrayKlassObjs[T_BOOLEAN] = _boolArrayKlassObj;
   282         _typeArrayKlassObjs[T_CHAR]    = _charArrayKlassObj;
   283         _typeArrayKlassObjs[T_FLOAT]   = _singleArrayKlassObj;
   284         _typeArrayKlassObjs[T_DOUBLE]  = _doubleArrayKlassObj;
   285         _typeArrayKlassObjs[T_BYTE]    = _byteArrayKlassObj;
   286         _typeArrayKlassObjs[T_SHORT]   = _shortArrayKlassObj;
   287         _typeArrayKlassObjs[T_INT]     = _intArrayKlassObj;
   288         _typeArrayKlassObjs[T_LONG]    = _longArrayKlassObj;
   290         ClassLoaderData* null_cld = ClassLoaderData::the_null_class_loader_data();
   292         _the_array_interfaces_array = MetadataFactory::new_array<Klass*>(null_cld, 2, NULL, CHECK);
   293         _the_empty_int_array        = MetadataFactory::new_array<int>(null_cld, 0, CHECK);
   294         _the_empty_short_array      = MetadataFactory::new_array<u2>(null_cld, 0, CHECK);
   295         _the_empty_method_array     = MetadataFactory::new_array<Method*>(null_cld, 0, CHECK);
   296         _the_empty_klass_array      = MetadataFactory::new_array<Klass*>(null_cld, 0, CHECK);
   297       }
   298     }
   300     vmSymbols::initialize(CHECK);
   302     SystemDictionary::initialize(CHECK);
   304     Klass* ok = SystemDictionary::Object_klass();
   306     _the_null_string            = StringTable::intern("null", CHECK);
   307     _the_min_jint_string       = StringTable::intern("-2147483648", CHECK);
   309     if (UseSharedSpaces) {
   310       // Verify shared interfaces array.
   311       assert(_the_array_interfaces_array->at(0) ==
   312              SystemDictionary::Cloneable_klass(), "u3");
   313       assert(_the_array_interfaces_array->at(1) ==
   314              SystemDictionary::Serializable_klass(), "u3");
   315     } else {
   316       // Set up shared interfaces array.  (Do this before supers are set up.)
   317       _the_array_interfaces_array->at_put(0, SystemDictionary::Cloneable_klass());
   318       _the_array_interfaces_array->at_put(1, SystemDictionary::Serializable_klass());
   319     }
   321     initialize_basic_type_klass(boolArrayKlassObj(), CHECK);
   322     initialize_basic_type_klass(charArrayKlassObj(), CHECK);
   323     initialize_basic_type_klass(singleArrayKlassObj(), CHECK);
   324     initialize_basic_type_klass(doubleArrayKlassObj(), CHECK);
   325     initialize_basic_type_klass(byteArrayKlassObj(), CHECK);
   326     initialize_basic_type_klass(shortArrayKlassObj(), CHECK);
   327     initialize_basic_type_klass(intArrayKlassObj(), CHECK);
   328     initialize_basic_type_klass(longArrayKlassObj(), CHECK);
   329   } // end of core bootstrapping
   331   // Maybe this could be lifted up now that object array can be initialized
   332   // during the bootstrapping.
   334   // OLD
   335   // Initialize _objectArrayKlass after core bootstraping to make
   336   // sure the super class is set up properly for _objectArrayKlass.
   337   // ---
   338   // NEW
   339   // Since some of the old system object arrays have been converted to
   340   // ordinary object arrays, _objectArrayKlass will be loaded when
   341   // SystemDictionary::initialize(CHECK); is run. See the extra check
   342   // for Object_klass_loaded in objArrayKlassKlass::allocate_objArray_klass_impl.
   343   _objectArrayKlassObj = InstanceKlass::
   344     cast(SystemDictionary::Object_klass())->array_klass(1, CHECK);
   345   // OLD
   346   // Add the class to the class hierarchy manually to make sure that
   347   // its vtable is initialized after core bootstrapping is completed.
   348   // ---
   349   // New
   350   // Have already been initialized.
   351   _objectArrayKlassObj->append_to_sibling_list();
   353   // Compute is_jdk version flags.
   354   // Only 1.3 or later has the java.lang.Shutdown class.
   355   // Only 1.4 or later has the java.lang.CharSequence interface.
   356   // Only 1.5 or later has the java.lang.management.MemoryUsage class.
   357   if (JDK_Version::is_partially_initialized()) {
   358     uint8_t jdk_version;
   359     Klass* k = SystemDictionary::resolve_or_null(
   360         vmSymbols::java_lang_management_MemoryUsage(), THREAD);
   361     CLEAR_PENDING_EXCEPTION; // ignore exceptions
   362     if (k == NULL) {
   363       k = SystemDictionary::resolve_or_null(
   364           vmSymbols::java_lang_CharSequence(), THREAD);
   365       CLEAR_PENDING_EXCEPTION; // ignore exceptions
   366       if (k == NULL) {
   367         k = SystemDictionary::resolve_or_null(
   368             vmSymbols::java_lang_Shutdown(), THREAD);
   369         CLEAR_PENDING_EXCEPTION; // ignore exceptions
   370         if (k == NULL) {
   371           jdk_version = 2;
   372         } else {
   373           jdk_version = 3;
   374         }
   375       } else {
   376         jdk_version = 4;
   377       }
   378     } else {
   379       jdk_version = 5;
   380     }
   381     JDK_Version::fully_initialize(jdk_version);
   382   }
   384   #ifdef ASSERT
   385   if (FullGCALot) {
   386     // Allocate an array of dummy objects.
   387     // We'd like these to be at the bottom of the old generation,
   388     // so that when we free one and then collect,
   389     // (almost) the whole heap moves
   390     // and we find out if we actually update all the oops correctly.
   391     // But we can't allocate directly in the old generation,
   392     // so we allocate wherever, and hope that the first collection
   393     // moves these objects to the bottom of the old generation.
   394     // We can allocate directly in the permanent generation, so we do.
   395     int size;
   396     if (UseConcMarkSweepGC) {
   397       warning("Using +FullGCALot with concurrent mark sweep gc "
   398               "will not force all objects to relocate");
   399       size = FullGCALotDummies;
   400     } else {
   401       size = FullGCALotDummies * 2;
   402     }
   403     objArrayOop    naked_array = oopFactory::new_objArray(SystemDictionary::Object_klass(), size, CHECK);
   404     objArrayHandle dummy_array(THREAD, naked_array);
   405     int i = 0;
   406     while (i < size) {
   407         // Allocate dummy in old generation
   408       oop dummy = InstanceKlass::cast(SystemDictionary::Object_klass())->allocate_instance(CHECK);
   409       dummy_array->obj_at_put(i++, dummy);
   410     }
   411     {
   412       // Only modify the global variable inside the mutex.
   413       // If we had a race to here, the other dummy_array instances
   414       // and their elements just get dropped on the floor, which is fine.
   415       MutexLocker ml(FullGCALot_lock);
   416       if (_fullgc_alot_dummy_array == NULL) {
   417         _fullgc_alot_dummy_array = dummy_array();
   418       }
   419     }
   420     assert(i == _fullgc_alot_dummy_array->length(), "just checking");
   421   }
   422   #endif
   424   // Initialize dependency array for null class loader
   425   ClassLoaderData::the_null_class_loader_data()->init_dependencies(CHECK);
   427 }
   429 // CDS support for patching vtables in metadata in the shared archive.
   430 // All types inherited from Metadata have vtables, but not types inherited
   431 // from MetaspaceObj, because the latter does not have virtual functions.
   432 // If the metadata type has a vtable, it cannot be shared in the read-only
   433 // section of the CDS archive, because the vtable pointer is patched.
   434 static inline void add_vtable(void** list, int* n, void* o, int count) {
   435   guarantee((*n) < count, "vtable list too small");
   436   void* vtable = dereference_vptr(o);
   437   assert(*(void**)(vtable) != NULL, "invalid vtable");
   438   list[(*n)++] = vtable;
   439 }
   441 void Universe::init_self_patching_vtbl_list(void** list, int count) {
   442   int n = 0;
   443   { InstanceKlass o;          add_vtable(list, &n, &o, count); }
   444   { InstanceClassLoaderKlass o; add_vtable(list, &n, &o, count); }
   445   { InstanceMirrorKlass o;    add_vtable(list, &n, &o, count); }
   446   { InstanceRefKlass o;       add_vtable(list, &n, &o, count); }
   447   { TypeArrayKlass o;         add_vtable(list, &n, &o, count); }
   448   { ObjArrayKlass o;          add_vtable(list, &n, &o, count); }
   449   { Method o;                 add_vtable(list, &n, &o, count); }
   450   { ConstantPool o;           add_vtable(list, &n, &o, count); }
   451 }
   453 void Universe::initialize_basic_type_mirrors(TRAPS) {
   454     assert(_int_mirror==NULL, "basic type mirrors already initialized");
   455     _int_mirror     =
   456       java_lang_Class::create_basic_type_mirror("int",    T_INT, CHECK);
   457     _float_mirror   =
   458       java_lang_Class::create_basic_type_mirror("float",  T_FLOAT,   CHECK);
   459     _double_mirror  =
   460       java_lang_Class::create_basic_type_mirror("double", T_DOUBLE,  CHECK);
   461     _byte_mirror    =
   462       java_lang_Class::create_basic_type_mirror("byte",   T_BYTE, CHECK);
   463     _bool_mirror    =
   464       java_lang_Class::create_basic_type_mirror("boolean",T_BOOLEAN, CHECK);
   465     _char_mirror    =
   466       java_lang_Class::create_basic_type_mirror("char",   T_CHAR, CHECK);
   467     _long_mirror    =
   468       java_lang_Class::create_basic_type_mirror("long",   T_LONG, CHECK);
   469     _short_mirror   =
   470       java_lang_Class::create_basic_type_mirror("short",  T_SHORT,   CHECK);
   471     _void_mirror    =
   472       java_lang_Class::create_basic_type_mirror("void",   T_VOID, CHECK);
   474     _mirrors[T_INT]     = _int_mirror;
   475     _mirrors[T_FLOAT]   = _float_mirror;
   476     _mirrors[T_DOUBLE]  = _double_mirror;
   477     _mirrors[T_BYTE]    = _byte_mirror;
   478     _mirrors[T_BOOLEAN] = _bool_mirror;
   479     _mirrors[T_CHAR]    = _char_mirror;
   480     _mirrors[T_LONG]    = _long_mirror;
   481     _mirrors[T_SHORT]   = _short_mirror;
   482     _mirrors[T_VOID]    = _void_mirror;
   483   //_mirrors[T_OBJECT]  = InstanceKlass::cast(_object_klass)->java_mirror();
   484   //_mirrors[T_ARRAY]   = InstanceKlass::cast(_object_klass)->java_mirror();
   485 }
   487 void Universe::fixup_mirrors(TRAPS) {
   488   // Bootstrap problem: all classes gets a mirror (java.lang.Class instance) assigned eagerly,
   489   // but we cannot do that for classes created before java.lang.Class is loaded. Here we simply
   490   // walk over permanent objects created so far (mostly classes) and fixup their mirrors. Note
   491   // that the number of objects allocated at this point is very small.
   492   assert(SystemDictionary::Class_klass_loaded(), "java.lang.Class should be loaded");
   493   HandleMark hm(THREAD);
   494   // Cache the start of the static fields
   495   InstanceMirrorKlass::init_offset_of_static_fields();
   497   GrowableArray <Klass*>* list = java_lang_Class::fixup_mirror_list();
   498   int list_length = list->length();
   499   for (int i = 0; i < list_length; i++) {
   500     Klass* k = list->at(i);
   501     assert(k->is_klass(), "List should only hold classes");
   502     EXCEPTION_MARK;
   503     KlassHandle kh(THREAD, k);
   504     java_lang_Class::fixup_mirror(kh, CATCH);
   505 }
   506   delete java_lang_Class::fixup_mirror_list();
   507   java_lang_Class::set_fixup_mirror_list(NULL);
   508 }
   510 static bool has_run_finalizers_on_exit = false;
   512 void Universe::run_finalizers_on_exit() {
   513   if (has_run_finalizers_on_exit) return;
   514   has_run_finalizers_on_exit = true;
   516   // Called on VM exit. This ought to be run in a separate thread.
   517   if (TraceReferenceGC) tty->print_cr("Callback to run finalizers on exit");
   518   {
   519     PRESERVE_EXCEPTION_MARK;
   520     KlassHandle finalizer_klass(THREAD, SystemDictionary::Finalizer_klass());
   521     JavaValue result(T_VOID);
   522     JavaCalls::call_static(
   523       &result,
   524       finalizer_klass,
   525       vmSymbols::run_finalizers_on_exit_name(),
   526       vmSymbols::void_method_signature(),
   527       THREAD
   528     );
   529     // Ignore any pending exceptions
   530     CLEAR_PENDING_EXCEPTION;
   531   }
   532 }
   535 // initialize_vtable could cause gc if
   536 // 1) we specified true to initialize_vtable and
   537 // 2) this ran after gc was enabled
   538 // In case those ever change we use handles for oops
   539 void Universe::reinitialize_vtable_of(KlassHandle k_h, TRAPS) {
   540   // init vtable of k and all subclasses
   541   Klass* ko = k_h();
   542   klassVtable* vt = ko->vtable();
   543   if (vt) vt->initialize_vtable(false, CHECK);
   544   if (ko->oop_is_instance()) {
   545     InstanceKlass* ik = (InstanceKlass*)ko;
   546     for (KlassHandle s_h(THREAD, ik->subklass());
   547          s_h() != NULL;
   548          s_h = KlassHandle(THREAD, s_h()->next_sibling())) {
   549       reinitialize_vtable_of(s_h, CHECK);
   550     }
   551   }
   552 }
   555 void initialize_itable_for_klass(Klass* k, TRAPS) {
   556   InstanceKlass::cast(k)->itable()->initialize_itable(false, CHECK);
   557 }
   560 void Universe::reinitialize_itables(TRAPS) {
   561   SystemDictionary::classes_do(initialize_itable_for_klass, CHECK);
   563 }
   566 bool Universe::on_page_boundary(void* addr) {
   567   return ((uintptr_t) addr) % os::vm_page_size() == 0;
   568 }
   571 bool Universe::should_fill_in_stack_trace(Handle throwable) {
   572   // never attempt to fill in the stack trace of preallocated errors that do not have
   573   // backtrace. These errors are kept alive forever and may be "re-used" when all
   574   // preallocated errors with backtrace have been consumed. Also need to avoid
   575   // a potential loop which could happen if an out of memory occurs when attempting
   576   // to allocate the backtrace.
   577   return ((throwable() != Universe::_out_of_memory_error_java_heap) &&
   578           (throwable() != Universe::_out_of_memory_error_metaspace)  &&
   579           (throwable() != Universe::_out_of_memory_error_class_metaspace)  &&
   580           (throwable() != Universe::_out_of_memory_error_array_size) &&
   581           (throwable() != Universe::_out_of_memory_error_gc_overhead_limit) &&
   582           (throwable() != Universe::_out_of_memory_error_realloc_objects));
   583 }
   586 oop Universe::gen_out_of_memory_error(oop default_err) {
   587   // generate an out of memory error:
   588   // - if there is a preallocated error with backtrace available then return it wth
   589   //   a filled in stack trace.
   590   // - if there are no preallocated errors with backtrace available then return
   591   //   an error without backtrace.
   592   int next;
   593   if (_preallocated_out_of_memory_error_avail_count > 0) {
   594     next = (int)Atomic::add(-1, &_preallocated_out_of_memory_error_avail_count);
   595     assert(next < (int)PreallocatedOutOfMemoryErrorCount, "avail count is corrupt");
   596   } else {
   597     next = -1;
   598   }
   599   if (next < 0) {
   600     // all preallocated errors have been used.
   601     // return default
   602     return default_err;
   603   } else {
   604     // get the error object at the slot and set set it to NULL so that the
   605     // array isn't keeping it alive anymore.
   606     oop exc = preallocated_out_of_memory_errors()->obj_at(next);
   607     assert(exc != NULL, "slot has been used already");
   608     preallocated_out_of_memory_errors()->obj_at_put(next, NULL);
   610     // use the message from the default error
   611     oop msg = java_lang_Throwable::message(default_err);
   612     assert(msg != NULL, "no message");
   613     java_lang_Throwable::set_message(exc, msg);
   615     // populate the stack trace and return it.
   616     java_lang_Throwable::fill_in_stack_trace_of_preallocated_backtrace(exc);
   617     return exc;
   618   }
   619 }
   621 intptr_t Universe::_non_oop_bits = 0;
   623 void* Universe::non_oop_word() {
   624   // Neither the high bits nor the low bits of this value is allowed
   625   // to look like (respectively) the high or low bits of a real oop.
   626   //
   627   // High and low are CPU-specific notions, but low always includes
   628   // the low-order bit.  Since oops are always aligned at least mod 4,
   629   // setting the low-order bit will ensure that the low half of the
   630   // word will never look like that of a real oop.
   631   //
   632   // Using the OS-supplied non-memory-address word (usually 0 or -1)
   633   // will take care of the high bits, however many there are.
   635   if (_non_oop_bits == 0) {
   636     _non_oop_bits = (intptr_t)os::non_memory_address_word() | 1;
   637   }
   639   return (void*)_non_oop_bits;
   640 }
   642 jint universe_init() {
   643   assert(!Universe::_fully_initialized, "called after initialize_vtables");
   644   guarantee(1 << LogHeapWordSize == sizeof(HeapWord),
   645          "LogHeapWordSize is incorrect.");
   646   guarantee(sizeof(oop) >= sizeof(HeapWord), "HeapWord larger than oop?");
   647   guarantee(sizeof(oop) % sizeof(HeapWord) == 0,
   648             "oop size is not not a multiple of HeapWord size");
   649   TraceTime timer("Genesis", TraceStartupTime);
   650   JavaClasses::compute_hard_coded_offsets();
   652   jint status = Universe::initialize_heap();
   653   if (status != JNI_OK) {
   654     return status;
   655   }
   657   Metaspace::global_initialize();
   659   // Create memory for metadata.  Must be after initializing heap for
   660   // DumpSharedSpaces.
   661   ClassLoaderData::init_null_class_loader_data();
   663   // We have a heap so create the Method* caches before
   664   // Metaspace::initialize_shared_spaces() tries to populate them.
   665   Universe::_finalizer_register_cache = new LatestMethodCache();
   666   Universe::_loader_addClass_cache    = new LatestMethodCache();
   667   Universe::_pd_implies_cache         = new LatestMethodCache();
   668   Universe::_throw_illegal_access_error_cache = new LatestMethodCache();
   670   if (UseSharedSpaces) {
   671     // Read the data structures supporting the shared spaces (shared
   672     // system dictionary, symbol table, etc.).  After that, access to
   673     // the file (other than the mapped regions) is no longer needed, and
   674     // the file is closed. Closing the file does not affect the
   675     // currently mapped regions.
   676     MetaspaceShared::initialize_shared_spaces();
   677     StringTable::create_table();
   678   } else {
   679     SymbolTable::create_table();
   680     StringTable::create_table();
   681     ClassLoader::create_package_info_table();
   683     if (DumpSharedSpaces) {
   684       MetaspaceShared::prepare_for_dumping();
   685     }
   686   }
   687   if (strlen(VerifySubSet) > 0) {
   688     Universe::initialize_verify_flags();
   689   }
   691   return JNI_OK;
   692 }
   694 // Choose the heap base address and oop encoding mode
   695 // when compressed oops are used:
   696 // Unscaled  - Use 32-bits oops without encoding when
   697 //     NarrowOopHeapBaseMin + heap_size < 4Gb
   698 // ZeroBased - Use zero based compressed oops with encoding when
   699 //     NarrowOopHeapBaseMin + heap_size < 32Gb
   700 // HeapBased - Use compressed oops with heap base + encoding.
   702 // 4Gb
   703 static const uint64_t UnscaledOopHeapMax = (uint64_t(max_juint) + 1);
   704 // 32Gb
   705 // OopEncodingHeapMax == UnscaledOopHeapMax << LogMinObjAlignmentInBytes;
   707 char* Universe::preferred_heap_base(size_t heap_size, size_t alignment, NARROW_OOP_MODE mode) {
   708   assert(is_size_aligned((size_t)OopEncodingHeapMax, alignment), "Must be");
   709   assert(is_size_aligned((size_t)UnscaledOopHeapMax, alignment), "Must be");
   710   assert(is_size_aligned(heap_size, alignment), "Must be");
   712   uintx heap_base_min_address_aligned = align_size_up(HeapBaseMinAddress, alignment);
   714   size_t base = 0;
   715 #ifdef _LP64
   716   if (UseCompressedOops) {
   717     assert(mode == UnscaledNarrowOop  ||
   718            mode == ZeroBasedNarrowOop ||
   719            mode == HeapBasedNarrowOop, "mode is invalid");
   720     const size_t total_size = heap_size + heap_base_min_address_aligned;
   721     // Return specified base for the first request.
   722     if (!FLAG_IS_DEFAULT(HeapBaseMinAddress) && (mode == UnscaledNarrowOop)) {
   723       base = heap_base_min_address_aligned;
   725     // If the total size is small enough to allow UnscaledNarrowOop then
   726     // just use UnscaledNarrowOop.
   727     } else if ((total_size <= OopEncodingHeapMax) && (mode != HeapBasedNarrowOop)) {
   728       if ((total_size <= UnscaledOopHeapMax) && (mode == UnscaledNarrowOop) &&
   729           (Universe::narrow_oop_shift() == 0)) {
   730         // Use 32-bits oops without encoding and
   731         // place heap's top on the 4Gb boundary
   732         base = (UnscaledOopHeapMax - heap_size);
   733       } else {
   734         // Can't reserve with NarrowOopShift == 0
   735         Universe::set_narrow_oop_shift(LogMinObjAlignmentInBytes);
   737         if (mode == UnscaledNarrowOop ||
   738             mode == ZeroBasedNarrowOop && total_size <= UnscaledOopHeapMax) {
   740           // Use zero based compressed oops with encoding and
   741           // place heap's top on the 32Gb boundary in case
   742           // total_size > 4Gb or failed to reserve below 4Gb.
   743           uint64_t heap_top = OopEncodingHeapMax;
   745           // For small heaps, save some space for compressed class pointer
   746           // space so it can be decoded with no base.
   747           if (UseCompressedClassPointers && !UseSharedSpaces &&
   748               OopEncodingHeapMax <= 32*G) {
   750             uint64_t class_space = align_size_up(CompressedClassSpaceSize, alignment);
   751             assert(is_size_aligned((size_t)OopEncodingHeapMax-class_space,
   752                    alignment), "difference must be aligned too");
   753             uint64_t new_top = OopEncodingHeapMax-class_space;
   755             if (total_size <= new_top) {
   756               heap_top = new_top;
   757             }
   758           }
   760           // Align base to the adjusted top of the heap
   761           base = heap_top - heap_size;
   762         }
   763       }
   764     } else {
   765       // UnscaledNarrowOop encoding didn't work, and no base was found for ZeroBasedOops or
   766       // HeapBasedNarrowOop encoding was requested.  So, can't reserve below 32Gb.
   767       Universe::set_narrow_oop_shift(LogMinObjAlignmentInBytes);
   768     }
   770     // Set narrow_oop_base and narrow_oop_use_implicit_null_checks
   771     // used in ReservedHeapSpace() constructors.
   772     // The final values will be set in initialize_heap() below.
   773     if ((base != 0) && ((base + heap_size) <= OopEncodingHeapMax)) {
   774       // Use zero based compressed oops
   775       Universe::set_narrow_oop_base(NULL);
   776       // Don't need guard page for implicit checks in indexed
   777       // addressing mode with zero based Compressed Oops.
   778       Universe::set_narrow_oop_use_implicit_null_checks(true);
   779     } else {
   780       // Set to a non-NULL value so the ReservedSpace ctor computes
   781       // the correct no-access prefix.
   782       // The final value will be set in initialize_heap() below.
   783       Universe::set_narrow_oop_base((address)UnscaledOopHeapMax);
   784 #if defined(_WIN64) || defined(AIX)
   785       if (UseLargePages) {
   786         // Cannot allocate guard pages for implicit checks in indexed
   787         // addressing mode when large pages are specified on windows.
   788         Universe::set_narrow_oop_use_implicit_null_checks(false);
   789       }
   790 #endif //  _WIN64
   791     }
   792   }
   793 #endif
   795   assert(is_ptr_aligned((char*)base, alignment), "Must be");
   796   return (char*)base; // also return NULL (don't care) for 32-bit VM
   797 }
   799 jint Universe::initialize_heap() {
   801   if (UseParallelGC) {
   802 #if INCLUDE_ALL_GCS
   803     Universe::_collectedHeap = new ParallelScavengeHeap();
   804 #else  // INCLUDE_ALL_GCS
   805     fatal("UseParallelGC not supported in this VM.");
   806 #endif // INCLUDE_ALL_GCS
   808   } else if (UseG1GC) {
   809 #if INCLUDE_ALL_GCS
   810     G1CollectorPolicyExt* g1p = new G1CollectorPolicyExt();
   811     g1p->initialize_all();
   812     G1CollectedHeap* g1h = new G1CollectedHeap(g1p);
   813     Universe::_collectedHeap = g1h;
   814 #else  // INCLUDE_ALL_GCS
   815     fatal("UseG1GC not supported in java kernel vm.");
   816 #endif // INCLUDE_ALL_GCS
   818   } else {
   819     GenCollectorPolicy *gc_policy;
   821     if (UseSerialGC) {
   822       gc_policy = new MarkSweepPolicy();
   823     } else if (UseConcMarkSweepGC) {
   824 #if INCLUDE_ALL_GCS
   825       if (UseAdaptiveSizePolicy) {
   826         gc_policy = new ASConcurrentMarkSweepPolicy();
   827       } else {
   828         gc_policy = new ConcurrentMarkSweepPolicy();
   829       }
   830 #else  // INCLUDE_ALL_GCS
   831     fatal("UseConcMarkSweepGC not supported in this VM.");
   832 #endif // INCLUDE_ALL_GCS
   833     } else { // default old generation
   834       gc_policy = new MarkSweepPolicy();
   835     }
   836     gc_policy->initialize_all();
   838     Universe::_collectedHeap = new GenCollectedHeap(gc_policy);
   839   }
   841   ThreadLocalAllocBuffer::set_max_size(Universe::heap()->max_tlab_size());
   843   jint status = Universe::heap()->initialize();
   844   if (status != JNI_OK) {
   845     return status;
   846   }
   848 #ifdef _LP64
   849   if (UseCompressedOops) {
   850     // Subtract a page because something can get allocated at heap base.
   851     // This also makes implicit null checking work, because the
   852     // memory+1 page below heap_base needs to cause a signal.
   853     // See needs_explicit_null_check.
   854     // Only set the heap base for compressed oops because it indicates
   855     // compressed oops for pstack code.
   856     if (((uint64_t)Universe::heap()->reserved_region().end() > OopEncodingHeapMax)) {
   857       // Can't reserve heap below 32Gb.
   858       // keep the Universe::narrow_oop_base() set in Universe::reserve_heap()
   859       Universe::set_narrow_oop_shift(LogMinObjAlignmentInBytes);
   860 #ifdef AIX
   861       // There is no protected page before the heap. This assures all oops
   862       // are decoded so that NULL is preserved, so this page will not be accessed.
   863       Universe::set_narrow_oop_use_implicit_null_checks(false);
   864 #endif
   865     } else {
   866       Universe::set_narrow_oop_base(0);
   867 #ifdef _WIN64
   868       if (!Universe::narrow_oop_use_implicit_null_checks()) {
   869         // Don't need guard page for implicit checks in indexed addressing
   870         // mode with zero based Compressed Oops.
   871         Universe::set_narrow_oop_use_implicit_null_checks(true);
   872       }
   873 #endif //  _WIN64
   874       if((uint64_t)Universe::heap()->reserved_region().end() > UnscaledOopHeapMax) {
   875         // Can't reserve heap below 4Gb.
   876         Universe::set_narrow_oop_shift(LogMinObjAlignmentInBytes);
   877       } else {
   878         Universe::set_narrow_oop_shift(0);
   879       }
   880     }
   882     Universe::set_narrow_ptrs_base(Universe::narrow_oop_base());
   884     if (PrintCompressedOopsMode || (PrintMiscellaneous && Verbose)) {
   885       Universe::print_compressed_oops_mode();
   886     }
   887   }
   888   // Universe::narrow_oop_base() is one page below the heap.
   889   assert((intptr_t)Universe::narrow_oop_base() <= (intptr_t)(Universe::heap()->base() -
   890          os::vm_page_size()) ||
   891          Universe::narrow_oop_base() == NULL, "invalid value");
   892   assert(Universe::narrow_oop_shift() == LogMinObjAlignmentInBytes ||
   893          Universe::narrow_oop_shift() == 0, "invalid value");
   894 #endif
   896   // We will never reach the CATCH below since Exceptions::_throw will cause
   897   // the VM to exit if an exception is thrown during initialization
   899   if (UseTLAB) {
   900     assert(Universe::heap()->supports_tlab_allocation(),
   901            "Should support thread-local allocation buffers");
   902     ThreadLocalAllocBuffer::startup_initialization();
   903   }
   904   return JNI_OK;
   905 }
   907 void Universe::print_compressed_oops_mode() {
   908   tty->cr();
   909   tty->print("heap address: " PTR_FORMAT ", size: " SIZE_FORMAT " MB",
   910               Universe::heap()->base(), Universe::heap()->reserved_region().byte_size()/M);
   912   tty->print(", Compressed Oops mode: %s", narrow_oop_mode_to_string(narrow_oop_mode()));
   914   if (Universe::narrow_oop_base() != 0) {
   915     tty->print(":" PTR_FORMAT, Universe::narrow_oop_base());
   916   }
   918   if (Universe::narrow_oop_shift() != 0) {
   919     tty->print(", Oop shift amount: %d", Universe::narrow_oop_shift());
   920   }
   922   tty->cr();
   923   tty->cr();
   924 }
   926 // Reserve the Java heap, which is now the same for all GCs.
   927 ReservedSpace Universe::reserve_heap(size_t heap_size, size_t alignment) {
   928   assert(alignment <= Arguments::conservative_max_heap_alignment(),
   929       err_msg("actual alignment "SIZE_FORMAT" must be within maximum heap alignment "SIZE_FORMAT,
   930           alignment, Arguments::conservative_max_heap_alignment()));
   931   size_t total_reserved = align_size_up(heap_size, alignment);
   932   assert(!UseCompressedOops || (total_reserved <= (OopEncodingHeapMax - os::vm_page_size())),
   933       "heap size is too big for compressed oops");
   935   bool use_large_pages = UseLargePages && is_size_aligned(alignment, os::large_page_size());
   936   assert(!UseLargePages
   937       || UseParallelGC
   938       || use_large_pages, "Wrong alignment to use large pages");
   940   char* addr = Universe::preferred_heap_base(total_reserved, alignment, Universe::UnscaledNarrowOop);
   942   ReservedHeapSpace total_rs(total_reserved, alignment, use_large_pages, addr);
   944   if (UseCompressedOops) {
   945     if (addr != NULL && !total_rs.is_reserved()) {
   946       // Failed to reserve at specified address - the requested memory
   947       // region is taken already, for example, by 'java' launcher.
   948       // Try again to reserver heap higher.
   949       addr = Universe::preferred_heap_base(total_reserved, alignment, Universe::ZeroBasedNarrowOop);
   951       ReservedHeapSpace total_rs0(total_reserved, alignment,
   952           use_large_pages, addr);
   954       if (addr != NULL && !total_rs0.is_reserved()) {
   955         // Failed to reserve at specified address again - give up.
   956         addr = Universe::preferred_heap_base(total_reserved, alignment, Universe::HeapBasedNarrowOop);
   957         assert(addr == NULL, "");
   959         ReservedHeapSpace total_rs1(total_reserved, alignment,
   960             use_large_pages, addr);
   961         total_rs = total_rs1;
   962       } else {
   963         total_rs = total_rs0;
   964       }
   965     }
   966   }
   968   if (!total_rs.is_reserved()) {
   969     vm_exit_during_initialization(err_msg("Could not reserve enough space for " SIZE_FORMAT "KB object heap", total_reserved/K));
   970     return total_rs;
   971   }
   973   if (UseCompressedOops) {
   974     // Universe::initialize_heap() will reset this to NULL if unscaled
   975     // or zero-based narrow oops are actually used.
   976     address base = (address)(total_rs.base() - os::vm_page_size());
   977     Universe::set_narrow_oop_base(base);
   978   }
   979   return total_rs;
   980 }
   983 // It's the caller's responsibility to ensure glitch-freedom
   984 // (if required).
   985 void Universe::update_heap_info_at_gc() {
   986   _heap_capacity_at_last_gc = heap()->capacity();
   987   _heap_used_at_last_gc     = heap()->used();
   988 }
   991 const char* Universe::narrow_oop_mode_to_string(Universe::NARROW_OOP_MODE mode) {
   992   switch (mode) {
   993     case UnscaledNarrowOop:
   994       return "32-bit";
   995     case ZeroBasedNarrowOop:
   996       return "Zero based";
   997     case HeapBasedNarrowOop:
   998       return "Non-zero based";
   999   }
  1001   ShouldNotReachHere();
  1002   return "";
  1006 Universe::NARROW_OOP_MODE Universe::narrow_oop_mode() {
  1007   if (narrow_oop_base() != 0) {
  1008     return HeapBasedNarrowOop;
  1011   if (narrow_oop_shift() != 0) {
  1012     return ZeroBasedNarrowOop;
  1015   return UnscaledNarrowOop;
  1019 void universe2_init() {
  1020   EXCEPTION_MARK;
  1021   Universe::genesis(CATCH);
  1025 // This function is defined in JVM.cpp
  1026 extern void initialize_converter_functions();
  1028 bool universe_post_init() {
  1029   assert(!is_init_completed(), "Error: initialization not yet completed!");
  1030   Universe::_fully_initialized = true;
  1031   EXCEPTION_MARK;
  1032   { ResourceMark rm;
  1033     Interpreter::initialize();      // needed for interpreter entry points
  1034     if (!UseSharedSpaces) {
  1035       HandleMark hm(THREAD);
  1036       KlassHandle ok_h(THREAD, SystemDictionary::Object_klass());
  1037       Universe::reinitialize_vtable_of(ok_h, CHECK_false);
  1038       Universe::reinitialize_itables(CHECK_false);
  1042   HandleMark hm(THREAD);
  1043   Klass* k;
  1044   instanceKlassHandle k_h;
  1045     // Setup preallocated empty java.lang.Class array
  1046     Universe::_the_empty_class_klass_array = oopFactory::new_objArray(SystemDictionary::Class_klass(), 0, CHECK_false);
  1048     // Setup preallocated OutOfMemoryError errors
  1049     k = SystemDictionary::resolve_or_fail(vmSymbols::java_lang_OutOfMemoryError(), true, CHECK_false);
  1050     k_h = instanceKlassHandle(THREAD, k);
  1051     Universe::_out_of_memory_error_java_heap = k_h->allocate_instance(CHECK_false);
  1052     Universe::_out_of_memory_error_metaspace = k_h->allocate_instance(CHECK_false);
  1053     Universe::_out_of_memory_error_class_metaspace = k_h->allocate_instance(CHECK_false);
  1054     Universe::_out_of_memory_error_array_size = k_h->allocate_instance(CHECK_false);
  1055     Universe::_out_of_memory_error_gc_overhead_limit =
  1056       k_h->allocate_instance(CHECK_false);
  1057     Universe::_out_of_memory_error_realloc_objects = k_h->allocate_instance(CHECK_false);
  1059     // Setup preallocated NullPointerException
  1060     // (this is currently used for a cheap & dirty solution in compiler exception handling)
  1061     k = SystemDictionary::resolve_or_fail(vmSymbols::java_lang_NullPointerException(), true, CHECK_false);
  1062     Universe::_null_ptr_exception_instance = InstanceKlass::cast(k)->allocate_instance(CHECK_false);
  1063     // Setup preallocated ArithmeticException
  1064     // (this is currently used for a cheap & dirty solution in compiler exception handling)
  1065     k = SystemDictionary::resolve_or_fail(vmSymbols::java_lang_ArithmeticException(), true, CHECK_false);
  1066     Universe::_arithmetic_exception_instance = InstanceKlass::cast(k)->allocate_instance(CHECK_false);
  1067     // Virtual Machine Error for when we get into a situation we can't resolve
  1068     k = SystemDictionary::resolve_or_fail(
  1069       vmSymbols::java_lang_VirtualMachineError(), true, CHECK_false);
  1070     bool linked = InstanceKlass::cast(k)->link_class_or_fail(CHECK_false);
  1071     if (!linked) {
  1072       tty->print_cr("Unable to link/verify VirtualMachineError class");
  1073       return false; // initialization failed
  1075     Universe::_virtual_machine_error_instance =
  1076       InstanceKlass::cast(k)->allocate_instance(CHECK_false);
  1078     Universe::_vm_exception = InstanceKlass::cast(k)->allocate_instance(CHECK_false);
  1080   if (!DumpSharedSpaces) {
  1081     // These are the only Java fields that are currently set during shared space dumping.
  1082     // We prefer to not handle this generally, so we always reinitialize these detail messages.
  1083     Handle msg = java_lang_String::create_from_str("Java heap space", CHECK_false);
  1084     java_lang_Throwable::set_message(Universe::_out_of_memory_error_java_heap, msg());
  1086     msg = java_lang_String::create_from_str("Metaspace", CHECK_false);
  1087     java_lang_Throwable::set_message(Universe::_out_of_memory_error_metaspace, msg());
  1088     msg = java_lang_String::create_from_str("Compressed class space", CHECK_false);
  1089     java_lang_Throwable::set_message(Universe::_out_of_memory_error_class_metaspace, msg());
  1091     msg = java_lang_String::create_from_str("Requested array size exceeds VM limit", CHECK_false);
  1092     java_lang_Throwable::set_message(Universe::_out_of_memory_error_array_size, msg());
  1094     msg = java_lang_String::create_from_str("GC overhead limit exceeded", CHECK_false);
  1095     java_lang_Throwable::set_message(Universe::_out_of_memory_error_gc_overhead_limit, msg());
  1097     msg = java_lang_String::create_from_str("Java heap space: failed reallocation of scalar replaced objects", CHECK_false);
  1098     java_lang_Throwable::set_message(Universe::_out_of_memory_error_realloc_objects, msg());
  1100     msg = java_lang_String::create_from_str("/ by zero", CHECK_false);
  1101     java_lang_Throwable::set_message(Universe::_arithmetic_exception_instance, msg());
  1103     // Setup the array of errors that have preallocated backtrace
  1104     k = Universe::_out_of_memory_error_java_heap->klass();
  1105     assert(k->name() == vmSymbols::java_lang_OutOfMemoryError(), "should be out of memory error");
  1106     k_h = instanceKlassHandle(THREAD, k);
  1108     int len = (StackTraceInThrowable) ? (int)PreallocatedOutOfMemoryErrorCount : 0;
  1109     Universe::_preallocated_out_of_memory_error_array = oopFactory::new_objArray(k_h(), len, CHECK_false);
  1110     for (int i=0; i<len; i++) {
  1111       oop err = k_h->allocate_instance(CHECK_false);
  1112       Handle err_h = Handle(THREAD, err);
  1113       java_lang_Throwable::allocate_backtrace(err_h, CHECK_false);
  1114       Universe::preallocated_out_of_memory_errors()->obj_at_put(i, err_h());
  1116     Universe::_preallocated_out_of_memory_error_avail_count = (jint)len;
  1120   // Setup static method for registering finalizers
  1121   // The finalizer klass must be linked before looking up the method, in
  1122   // case it needs to get rewritten.
  1123   InstanceKlass::cast(SystemDictionary::Finalizer_klass())->link_class(CHECK_false);
  1124   Method* m = InstanceKlass::cast(SystemDictionary::Finalizer_klass())->find_method(
  1125                                   vmSymbols::register_method_name(),
  1126                                   vmSymbols::register_method_signature());
  1127   if (m == NULL || !m->is_static()) {
  1128     tty->print_cr("Unable to link/verify Finalizer.register method");
  1129     return false; // initialization failed (cannot throw exception yet)
  1131   Universe::_finalizer_register_cache->init(
  1132     SystemDictionary::Finalizer_klass(), m);
  1134   InstanceKlass::cast(SystemDictionary::misc_Unsafe_klass())->link_class(CHECK_false);
  1135   m = InstanceKlass::cast(SystemDictionary::misc_Unsafe_klass())->find_method(
  1136                                   vmSymbols::throwIllegalAccessError_name(),
  1137                                   vmSymbols::void_method_signature());
  1138   if (m != NULL && !m->is_static()) {
  1139     // Note null is okay; this method is used in itables, and if it is null,
  1140     // then AbstractMethodError is thrown instead.
  1141     tty->print_cr("Unable to link/verify Unsafe.throwIllegalAccessError method");
  1142     return false; // initialization failed (cannot throw exception yet)
  1144   Universe::_throw_illegal_access_error_cache->init(
  1145     SystemDictionary::misc_Unsafe_klass(), m);
  1147   // Setup method for registering loaded classes in class loader vector
  1148   InstanceKlass::cast(SystemDictionary::ClassLoader_klass())->link_class(CHECK_false);
  1149   m = InstanceKlass::cast(SystemDictionary::ClassLoader_klass())->find_method(vmSymbols::addClass_name(), vmSymbols::class_void_signature());
  1150   if (m == NULL || m->is_static()) {
  1151     tty->print_cr("Unable to link/verify ClassLoader.addClass method");
  1152     return false; // initialization failed (cannot throw exception yet)
  1154   Universe::_loader_addClass_cache->init(
  1155     SystemDictionary::ClassLoader_klass(), m);
  1157   // Setup method for checking protection domain
  1158   InstanceKlass::cast(SystemDictionary::ProtectionDomain_klass())->link_class(CHECK_false);
  1159   m = InstanceKlass::cast(SystemDictionary::ProtectionDomain_klass())->
  1160             find_method(vmSymbols::impliesCreateAccessControlContext_name(),
  1161                         vmSymbols::void_boolean_signature());
  1162   // Allow NULL which should only happen with bootstrapping.
  1163   if (m != NULL) {
  1164     if (m->is_static()) {
  1165       // NoSuchMethodException doesn't actually work because it tries to run the
  1166       // <init> function before java_lang_Class is linked. Print error and exit.
  1167       tty->print_cr("ProtectionDomain.impliesCreateAccessControlContext() has the wrong linkage");
  1168       return false; // initialization failed
  1170     Universe::_pd_implies_cache->init(
  1171       SystemDictionary::ProtectionDomain_klass(), m);
  1174   // The folowing is initializing converter functions for serialization in
  1175   // JVM.cpp. If we clean up the StrictMath code above we may want to find
  1176   // a better solution for this as well.
  1177   initialize_converter_functions();
  1179   // This needs to be done before the first scavenge/gc, since
  1180   // it's an input to soft ref clearing policy.
  1182     MutexLocker x(Heap_lock);
  1183     Universe::update_heap_info_at_gc();
  1186   // ("weak") refs processing infrastructure initialization
  1187   Universe::heap()->post_initialize();
  1189   // Initialize performance counters for metaspaces
  1190   MetaspaceCounters::initialize_performance_counters();
  1191   CompressedClassSpaceCounters::initialize_performance_counters();
  1193   MemoryService::add_metaspace_memory_pools();
  1195   MemoryService::set_universe_heap(Universe::_collectedHeap);
  1196 #if INCLUDE_CDS
  1197   if (UseSharedSpaces) {
  1198     SharedClassUtil::initialize(CHECK_false);
  1200 #endif
  1201   return true;
  1205 void Universe::compute_base_vtable_size() {
  1206   _base_vtable_size = ClassLoader::compute_Object_vtable();
  1210 // %%% The Universe::flush_foo methods belong in CodeCache.
  1212 // Flushes compiled methods dependent on dependee.
  1213 void Universe::flush_dependents_on(instanceKlassHandle dependee) {
  1214   assert_lock_strong(Compile_lock);
  1216   if (CodeCache::number_of_nmethods_with_dependencies() == 0) return;
  1218   // CodeCache can only be updated by a thread_in_VM and they will all be
  1219   // stopped dring the safepoint so CodeCache will be safe to update without
  1220   // holding the CodeCache_lock.
  1222   KlassDepChange changes(dependee);
  1224   // Compute the dependent nmethods
  1225   if (CodeCache::mark_for_deoptimization(changes) > 0) {
  1226     // At least one nmethod has been marked for deoptimization
  1227     VM_Deoptimize op;
  1228     VMThread::execute(&op);
  1232 // Flushes compiled methods dependent on a particular CallSite
  1233 // instance when its target is different than the given MethodHandle.
  1234 void Universe::flush_dependents_on(Handle call_site, Handle method_handle) {
  1235   assert_lock_strong(Compile_lock);
  1237   if (CodeCache::number_of_nmethods_with_dependencies() == 0) return;
  1239   // CodeCache can only be updated by a thread_in_VM and they will all be
  1240   // stopped dring the safepoint so CodeCache will be safe to update without
  1241   // holding the CodeCache_lock.
  1243   CallSiteDepChange changes(call_site(), method_handle());
  1245   // Compute the dependent nmethods that have a reference to a
  1246   // CallSite object.  We use InstanceKlass::mark_dependent_nmethod
  1247   // directly instead of CodeCache::mark_for_deoptimization because we
  1248   // want dependents on the call site class only not all classes in
  1249   // the ContextStream.
  1250   int marked = 0;
  1252     MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
  1253     InstanceKlass* call_site_klass = InstanceKlass::cast(call_site->klass());
  1254     marked = call_site_klass->mark_dependent_nmethods(changes);
  1256   if (marked > 0) {
  1257     // At least one nmethod has been marked for deoptimization
  1258     VM_Deoptimize op;
  1259     VMThread::execute(&op);
  1263 #ifdef HOTSWAP
  1264 // Flushes compiled methods dependent on dependee in the evolutionary sense
  1265 void Universe::flush_evol_dependents_on(instanceKlassHandle ev_k_h) {
  1266   // --- Compile_lock is not held. However we are at a safepoint.
  1267   assert_locked_or_safepoint(Compile_lock);
  1268   if (CodeCache::number_of_nmethods_with_dependencies() == 0) return;
  1270   // CodeCache can only be updated by a thread_in_VM and they will all be
  1271   // stopped dring the safepoint so CodeCache will be safe to update without
  1272   // holding the CodeCache_lock.
  1274   // Compute the dependent nmethods
  1275   if (CodeCache::mark_for_evol_deoptimization(ev_k_h) > 0) {
  1276     // At least one nmethod has been marked for deoptimization
  1278     // All this already happens inside a VM_Operation, so we'll do all the work here.
  1279     // Stuff copied from VM_Deoptimize and modified slightly.
  1281     // We do not want any GCs to happen while we are in the middle of this VM operation
  1282     ResourceMark rm;
  1283     DeoptimizationMarker dm;
  1285     // Deoptimize all activations depending on marked nmethods
  1286     Deoptimization::deoptimize_dependents();
  1288     // Make the dependent methods not entrant (in VM_Deoptimize they are made zombies)
  1289     CodeCache::make_marked_nmethods_not_entrant();
  1292 #endif // HOTSWAP
  1295 // Flushes compiled methods dependent on dependee
  1296 void Universe::flush_dependents_on_method(methodHandle m_h) {
  1297   // --- Compile_lock is not held. However we are at a safepoint.
  1298   assert_locked_or_safepoint(Compile_lock);
  1300   // CodeCache can only be updated by a thread_in_VM and they will all be
  1301   // stopped dring the safepoint so CodeCache will be safe to update without
  1302   // holding the CodeCache_lock.
  1304   // Compute the dependent nmethods
  1305   if (CodeCache::mark_for_deoptimization(m_h()) > 0) {
  1306     // At least one nmethod has been marked for deoptimization
  1308     // All this already happens inside a VM_Operation, so we'll do all the work here.
  1309     // Stuff copied from VM_Deoptimize and modified slightly.
  1311     // We do not want any GCs to happen while we are in the middle of this VM operation
  1312     ResourceMark rm;
  1313     DeoptimizationMarker dm;
  1315     // Deoptimize all activations depending on marked nmethods
  1316     Deoptimization::deoptimize_dependents();
  1318     // Make the dependent methods not entrant (in VM_Deoptimize they are made zombies)
  1319     CodeCache::make_marked_nmethods_not_entrant();
  1323 void Universe::print() {
  1324   print_on(gclog_or_tty);
  1327 void Universe::print_on(outputStream* st, bool extended) {
  1328   st->print_cr("Heap");
  1329   if (!extended) {
  1330     heap()->print_on(st);
  1331   } else {
  1332     heap()->print_extended_on(st);
  1336 void Universe::print_heap_at_SIGBREAK() {
  1337   if (PrintHeapAtSIGBREAK) {
  1338     MutexLocker hl(Heap_lock);
  1339     print_on(tty);
  1340     tty->cr();
  1341     tty->flush();
  1345 void Universe::print_heap_before_gc(outputStream* st, bool ignore_extended) {
  1346   st->print_cr("{Heap before GC invocations=%u (full %u):",
  1347                heap()->total_collections(),
  1348                heap()->total_full_collections());
  1349   if (!PrintHeapAtGCExtended || ignore_extended) {
  1350     heap()->print_on(st);
  1351   } else {
  1352     heap()->print_extended_on(st);
  1356 void Universe::print_heap_after_gc(outputStream* st, bool ignore_extended) {
  1357   st->print_cr("Heap after GC invocations=%u (full %u):",
  1358                heap()->total_collections(),
  1359                heap()->total_full_collections());
  1360   if (!PrintHeapAtGCExtended || ignore_extended) {
  1361     heap()->print_on(st);
  1362   } else {
  1363     heap()->print_extended_on(st);
  1365   st->print_cr("}");
  1368 void Universe::initialize_verify_flags() {
  1369   verify_flags = 0;
  1370   const char delimiter[] = " ,";
  1372   size_t length = strlen(VerifySubSet);
  1373   char* subset_list = NEW_C_HEAP_ARRAY(char, length + 1, mtInternal);
  1374   strncpy(subset_list, VerifySubSet, length + 1);
  1376   char* token = strtok(subset_list, delimiter);
  1377   while (token != NULL) {
  1378     if (strcmp(token, "threads") == 0) {
  1379       verify_flags |= Verify_Threads;
  1380     } else if (strcmp(token, "heap") == 0) {
  1381       verify_flags |= Verify_Heap;
  1382     } else if (strcmp(token, "symbol_table") == 0) {
  1383       verify_flags |= Verify_SymbolTable;
  1384     } else if (strcmp(token, "string_table") == 0) {
  1385       verify_flags |= Verify_StringTable;
  1386     } else if (strcmp(token, "codecache") == 0) {
  1387       verify_flags |= Verify_CodeCache;
  1388     } else if (strcmp(token, "dictionary") == 0) {
  1389       verify_flags |= Verify_SystemDictionary;
  1390     } else if (strcmp(token, "classloader_data_graph") == 0) {
  1391       verify_flags |= Verify_ClassLoaderDataGraph;
  1392     } else if (strcmp(token, "metaspace") == 0) {
  1393       verify_flags |= Verify_MetaspaceAux;
  1394     } else if (strcmp(token, "jni_handles") == 0) {
  1395       verify_flags |= Verify_JNIHandles;
  1396     } else if (strcmp(token, "c-heap") == 0) {
  1397       verify_flags |= Verify_CHeap;
  1398     } else if (strcmp(token, "codecache_oops") == 0) {
  1399       verify_flags |= Verify_CodeCacheOops;
  1400     } else {
  1401       vm_exit_during_initialization(err_msg("VerifySubSet: \'%s\' memory sub-system is unknown, please correct it", token));
  1403     token = strtok(NULL, delimiter);
  1405   FREE_C_HEAP_ARRAY(char, subset_list, mtInternal);
  1408 bool Universe::should_verify_subset(uint subset) {
  1409   if (verify_flags & subset) {
  1410     return true;
  1412   return false;
  1415 void Universe::verify(VerifyOption option, const char* prefix, bool silent) {
  1416   // The use of _verify_in_progress is a temporary work around for
  1417   // 6320749.  Don't bother with a creating a class to set and clear
  1418   // it since it is only used in this method and the control flow is
  1419   // straight forward.
  1420   _verify_in_progress = true;
  1422   COMPILER2_PRESENT(
  1423     assert(!DerivedPointerTable::is_active(),
  1424          "DPT should not be active during verification "
  1425          "(of thread stacks below)");
  1428   ResourceMark rm;
  1429   HandleMark hm;  // Handles created during verification can be zapped
  1430   _verify_count++;
  1432   if (!silent) gclog_or_tty->print("%s", prefix);
  1433   if (!silent) gclog_or_tty->print("[Verifying ");
  1434   if (should_verify_subset(Verify_Threads)) {
  1435     if (!silent) gclog_or_tty->print("Threads ");
  1436     Threads::verify();
  1438   if (should_verify_subset(Verify_Heap)) {
  1439     if (!silent) gclog_or_tty->print("Heap ");
  1440     heap()->verify(silent, option);
  1442   if (should_verify_subset(Verify_SymbolTable)) {
  1443     if (!silent) gclog_or_tty->print("SymbolTable ");
  1444     SymbolTable::verify();
  1446   if (should_verify_subset(Verify_StringTable)) {
  1447     if (!silent) gclog_or_tty->print("StringTable ");
  1448     StringTable::verify();
  1450   if (should_verify_subset(Verify_CodeCache)) {
  1452     MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
  1453     if (!silent) gclog_or_tty->print("CodeCache ");
  1454     CodeCache::verify();
  1457   if (should_verify_subset(Verify_SystemDictionary)) {
  1458     if (!silent) gclog_or_tty->print("SystemDictionary ");
  1459     SystemDictionary::verify();
  1461 #ifndef PRODUCT
  1462   if (should_verify_subset(Verify_ClassLoaderDataGraph)) {
  1463     if (!silent) gclog_or_tty->print("ClassLoaderDataGraph ");
  1464     ClassLoaderDataGraph::verify();
  1466 #endif
  1467   if (should_verify_subset(Verify_MetaspaceAux)) {
  1468     if (!silent) gclog_or_tty->print("MetaspaceAux ");
  1469     MetaspaceAux::verify_free_chunks();
  1471   if (should_verify_subset(Verify_JNIHandles)) {
  1472     if (!silent) gclog_or_tty->print("JNIHandles ");
  1473     JNIHandles::verify();
  1475   if (should_verify_subset(Verify_CHeap)) {
  1476     if (!silent) gclog_or_tty->print("C-heap ");
  1477     os::check_heap();
  1479   if (should_verify_subset(Verify_CodeCacheOops)) {
  1480     if (!silent) gclog_or_tty->print("CodeCache Oops ");
  1481     CodeCache::verify_oops();
  1483   if (!silent) gclog_or_tty->print_cr("]");
  1485   _verify_in_progress = false;
  1488 // Oop verification (see MacroAssembler::verify_oop)
  1490 static uintptr_t _verify_oop_data[2]   = {0, (uintptr_t)-1};
  1491 static uintptr_t _verify_klass_data[2] = {0, (uintptr_t)-1};
  1494 #ifndef PRODUCT
  1496 static void calculate_verify_data(uintptr_t verify_data[2],
  1497                                   HeapWord* low_boundary,
  1498                                   HeapWord* high_boundary) {
  1499   assert(low_boundary < high_boundary, "bad interval");
  1501   // decide which low-order bits we require to be clear:
  1502   size_t alignSize = MinObjAlignmentInBytes;
  1503   size_t min_object_size = CollectedHeap::min_fill_size();
  1505   // make an inclusive limit:
  1506   uintptr_t max = (uintptr_t)high_boundary - min_object_size*wordSize;
  1507   uintptr_t min = (uintptr_t)low_boundary;
  1508   assert(min < max, "bad interval");
  1509   uintptr_t diff = max ^ min;
  1511   // throw away enough low-order bits to make the diff vanish
  1512   uintptr_t mask = (uintptr_t)(-1);
  1513   while ((mask & diff) != 0)
  1514     mask <<= 1;
  1515   uintptr_t bits = (min & mask);
  1516   assert(bits == (max & mask), "correct mask");
  1517   // check an intermediate value between min and max, just to make sure:
  1518   assert(bits == ((min + (max-min)/2) & mask), "correct mask");
  1520   // require address alignment, too:
  1521   mask |= (alignSize - 1);
  1523   if (!(verify_data[0] == 0 && verify_data[1] == (uintptr_t)-1)) {
  1524     assert(verify_data[0] == mask && verify_data[1] == bits, "mask stability");
  1526   verify_data[0] = mask;
  1527   verify_data[1] = bits;
  1530 // Oop verification (see MacroAssembler::verify_oop)
  1532 uintptr_t Universe::verify_oop_mask() {
  1533   MemRegion m = heap()->reserved_region();
  1534   calculate_verify_data(_verify_oop_data,
  1535                         m.start(),
  1536                         m.end());
  1537   return _verify_oop_data[0];
  1542 uintptr_t Universe::verify_oop_bits() {
  1543   verify_oop_mask();
  1544   return _verify_oop_data[1];
  1547 uintptr_t Universe::verify_mark_mask() {
  1548   return markOopDesc::lock_mask_in_place;
  1551 uintptr_t Universe::verify_mark_bits() {
  1552   intptr_t mask = verify_mark_mask();
  1553   intptr_t bits = (intptr_t)markOopDesc::prototype();
  1554   assert((bits & ~mask) == 0, "no stray header bits");
  1555   return bits;
  1557 #endif // PRODUCT
  1560 void Universe::compute_verify_oop_data() {
  1561   verify_oop_mask();
  1562   verify_oop_bits();
  1563   verify_mark_mask();
  1564   verify_mark_bits();
  1568 void LatestMethodCache::init(Klass* k, Method* m) {
  1569   if (!UseSharedSpaces) {
  1570     _klass = k;
  1572 #ifndef PRODUCT
  1573   else {
  1574     // sharing initilization should have already set up _klass
  1575     assert(_klass != NULL, "just checking");
  1577 #endif
  1579   _method_idnum = m->method_idnum();
  1580   assert(_method_idnum >= 0, "sanity check");
  1584 Method* LatestMethodCache::get_method() {
  1585   if (klass() == NULL) return NULL;
  1586   InstanceKlass* ik = InstanceKlass::cast(klass());
  1587   Method* m = ik->method_with_idnum(method_idnum());
  1588   assert(m != NULL, "sanity check");
  1589   return m;
  1593 #ifdef ASSERT
  1594 // Release dummy object(s) at bottom of heap
  1595 bool Universe::release_fullgc_alot_dummy() {
  1596   MutexLocker ml(FullGCALot_lock);
  1597   if (_fullgc_alot_dummy_array != NULL) {
  1598     if (_fullgc_alot_dummy_next >= _fullgc_alot_dummy_array->length()) {
  1599       // No more dummies to release, release entire array instead
  1600       _fullgc_alot_dummy_array = NULL;
  1601       return false;
  1603     if (!UseConcMarkSweepGC) {
  1604       // Release dummy at bottom of old generation
  1605       _fullgc_alot_dummy_array->obj_at_put(_fullgc_alot_dummy_next++, NULL);
  1607     // Release dummy at bottom of permanent generation
  1608     _fullgc_alot_dummy_array->obj_at_put(_fullgc_alot_dummy_next++, NULL);
  1610   return true;
  1613 #endif // ASSERT

mercurial