1 /*
   2  * Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #include "precompiled.hpp"
  26 #include "classfile/classLoader.hpp"
  27 #include "classfile/classLoaderData.hpp"
  28 #include "classfile/javaClasses.hpp"
  29 #include "classfile/symbolTable.hpp"
  30 #include "classfile/systemDictionary.hpp"
  31 #include "classfile/vmSymbols.hpp"
  32 #include "code/codeCache.hpp"
  33 #include "code/dependencies.hpp"
  34 #include "gc_interface/collectedHeap.inline.hpp"
  35 #include "interpreter/interpreter.hpp"
  36 #include "memory/cardTableModRefBS.hpp"
  37 #include "memory/gcLocker.inline.hpp"
  38 #include "memory/genCollectedHeap.hpp"
  39 #include "memory/genRemSet.hpp"
  40 #include "memory/generation.hpp"
  41 #include "memory/metadataFactory.hpp"
  42 #include "memory/metaspaceShared.hpp"
  43 #include "memory/oopFactory.hpp"
  44 #include "memory/space.hpp"
  45 #include "memory/universe.hpp"
  46 #include "memory/universe.inline.hpp"
  47 #include "oops/constantPool.hpp"
  48 #include "oops/instanceClassLoaderKlass.hpp"
  49 #include "oops/instanceKlass.hpp"
  50 #include "oops/instanceMirrorKlass.hpp"
  51 #include "oops/instanceRefKlass.hpp"
  52 #include "oops/oop.inline.hpp"
  53 #include "oops/typeArrayKlass.hpp"
  54 #include "prims/jvmtiRedefineClassesTrace.hpp"
  55 #include "runtime/arguments.hpp"
  56 #include "runtime/deoptimization.hpp"
  57 #include "runtime/fprofiler.hpp"
  58 #include "runtime/handles.inline.hpp"
  59 #include "runtime/init.hpp"
  60 #include "runtime/java.hpp"
  61 #include "runtime/javaCalls.hpp"
  62 #include "runtime/sharedRuntime.hpp"
  63 #include "runtime/synchronizer.hpp"
  64 #include "runtime/thread.inline.hpp"
  65 #include "runtime/timer.hpp"
  66 #include "runtime/vm_operations.hpp"
  67 #include "services/memoryService.hpp"
  68 #include "utilities/copy.hpp"
  69 #include "utilities/events.hpp"
  70 #include "utilities/hashtable.inline.hpp"
  71 #include "utilities/preserveException.hpp"
  72 #include "utilities/macros.hpp"
  73 #if INCLUDE_ALL_GCS
  74 #include "gc_implementation/concurrentMarkSweep/cmsAdaptiveSizePolicy.hpp"
  75 #include "gc_implementation/concurrentMarkSweep/cmsCollectorPolicy.hpp"
  76 #include "gc_implementation/g1/g1CollectedHeap.inline.hpp"
  77 #include "gc_implementation/g1/g1CollectorPolicy.hpp"
  78 #include "gc_implementation/parallelScavenge/parallelScavengeHeap.hpp"
  79 #endif // INCLUDE_ALL_GCS
  80 
  81 // Known objects
  82 Klass* Universe::_boolArrayKlassObj                 = NULL;
  83 Klass* Universe::_byteArrayKlassObj                 = NULL;
  84 Klass* Universe::_charArrayKlassObj                 = NULL;
  85 Klass* Universe::_intArrayKlassObj                  = NULL;
  86 Klass* Universe::_shortArrayKlassObj                = NULL;
  87 Klass* Universe::_longArrayKlassObj                 = NULL;
  88 Klass* Universe::_singleArrayKlassObj               = NULL;
  89 Klass* Universe::_doubleArrayKlassObj               = NULL;
  90 Klass* Universe::_typeArrayKlassObjs[T_VOID+1]      = { NULL /*, NULL...*/ };
  91 Klass* Universe::_objectArrayKlassObj               = NULL;
  92 oop Universe::_int_mirror                             = NULL;
  93 oop Universe::_float_mirror                           = NULL;
  94 oop Universe::_double_mirror                          = NULL;
  95 oop Universe::_byte_mirror                            = NULL;
  96 oop Universe::_bool_mirror                            = NULL;
  97 oop Universe::_char_mirror                            = NULL;
  98 oop Universe::_long_mirror                            = NULL;
  99 oop Universe::_short_mirror                           = NULL;
 100 oop Universe::_void_mirror                            = NULL;
 101 oop Universe::_mirrors[T_VOID+1]                      = { NULL /*, NULL...*/ };
 102 oop Universe::_main_thread_group                      = NULL;
 103 oop Universe::_system_thread_group                    = NULL;
 104 objArrayOop Universe::_the_empty_class_klass_array    = NULL;
 105 Array<Klass*>* Universe::_the_array_interfaces_array = NULL;
 106 oop Universe::_the_null_string                        = NULL;
 107 oop Universe::_the_min_jint_string                   = NULL;
 108 LatestMethodOopCache* Universe::_finalizer_register_cache = NULL;
 109 LatestMethodOopCache* Universe::_loader_addClass_cache    = NULL;
 110 LatestMethodOopCache* Universe::_pd_implies_cache         = NULL;
 111 ActiveMethodOopsCache* Universe::_reflect_invoke_cache    = NULL;
 112 oop Universe::_out_of_memory_error_java_heap          = NULL;
 113 oop Universe::_out_of_memory_error_metaspace          = NULL;
 114 oop Universe::_out_of_memory_error_class_metaspace    = NULL;
 115 oop Universe::_out_of_memory_error_array_size         = NULL;
 116 oop Universe::_out_of_memory_error_gc_overhead_limit  = NULL;
 117 objArrayOop Universe::_preallocated_out_of_memory_error_array = NULL;
 118 volatile jint Universe::_preallocated_out_of_memory_error_avail_count = 0;
 119 bool Universe::_verify_in_progress                    = false;
 120 oop Universe::_null_ptr_exception_instance            = NULL;
 121 oop Universe::_arithmetic_exception_instance          = NULL;
 122 oop Universe::_virtual_machine_error_instance         = NULL;
 123 oop Universe::_vm_exception                           = NULL;
 124 Array<int>* Universe::_the_empty_int_array            = NULL;
 125 Array<u2>* Universe::_the_empty_short_array           = NULL;
 126 Array<Klass*>* Universe::_the_empty_klass_array     = NULL;
 127 Array<Method*>* Universe::_the_empty_method_array   = NULL;
 128 
 129 // These variables are guarded by FullGCALot_lock.
 130 debug_only(objArrayOop Universe::_fullgc_alot_dummy_array = NULL;)
 131 debug_only(int Universe::_fullgc_alot_dummy_next      = 0;)
 132 
 133 // Heap
 134 int             Universe::_verify_count = 0;
 135 
 136 int             Universe::_base_vtable_size = 0;
 137 bool            Universe::_bootstrapping = false;
 138 bool            Universe::_fully_initialized = false;
 139 
 140 size_t          Universe::_heap_capacity_at_last_gc;
 141 size_t          Universe::_heap_used_at_last_gc = 0;
 142 
 143 CollectedHeap*  Universe::_collectedHeap = NULL;
 144 
 145 NarrowPtrStruct Universe::_narrow_oop = { NULL, 0, true };
 146 NarrowPtrStruct Universe::_narrow_klass = { NULL, 0, true };
 147 address Universe::_narrow_ptrs_base;
 148 
 149 size_t          Universe::_class_metaspace_size;
 150 
 151 void Universe::basic_type_classes_do(void f(Klass*)) {
 152   f(boolArrayKlassObj());
 153   f(byteArrayKlassObj());
 154   f(charArrayKlassObj());
 155   f(intArrayKlassObj());
 156   f(shortArrayKlassObj());
 157   f(longArrayKlassObj());
 158   f(singleArrayKlassObj());
 159   f(doubleArrayKlassObj());
 160 }
 161 
 162 void Universe::oops_do(OopClosure* f, bool do_all) {
 163 
 164   f->do_oop((oop*) &_int_mirror);
 165   f->do_oop((oop*) &_float_mirror);
 166   f->do_oop((oop*) &_double_mirror);
 167   f->do_oop((oop*) &_byte_mirror);
 168   f->do_oop((oop*) &_bool_mirror);
 169   f->do_oop((oop*) &_char_mirror);
 170   f->do_oop((oop*) &_long_mirror);
 171   f->do_oop((oop*) &_short_mirror);
 172   f->do_oop((oop*) &_void_mirror);
 173 
 174   for (int i = T_BOOLEAN; i < T_VOID+1; i++) {
 175     f->do_oop((oop*) &_mirrors[i]);
 176   }
 177   assert(_mirrors[0] == NULL && _mirrors[T_BOOLEAN - 1] == NULL, "checking");
 178 
 179   f->do_oop((oop*)&_the_empty_class_klass_array);
 180   f->do_oop((oop*)&_the_null_string);
 181   f->do_oop((oop*)&_the_min_jint_string);
 182   f->do_oop((oop*)&_out_of_memory_error_java_heap);
 183   f->do_oop((oop*)&_out_of_memory_error_metaspace);
 184   f->do_oop((oop*)&_out_of_memory_error_class_metaspace);
 185   f->do_oop((oop*)&_out_of_memory_error_array_size);
 186   f->do_oop((oop*)&_out_of_memory_error_gc_overhead_limit);
 187     f->do_oop((oop*)&_preallocated_out_of_memory_error_array);
 188   f->do_oop((oop*)&_null_ptr_exception_instance);
 189   f->do_oop((oop*)&_arithmetic_exception_instance);
 190   f->do_oop((oop*)&_virtual_machine_error_instance);
 191   f->do_oop((oop*)&_main_thread_group);
 192   f->do_oop((oop*)&_system_thread_group);
 193   f->do_oop((oop*)&_vm_exception);
 194   debug_only(f->do_oop((oop*)&_fullgc_alot_dummy_array);)
 195 }
 196 
 197 // Serialize metadata in and out of CDS archive, not oops.
 198 void Universe::serialize(SerializeClosure* f, bool do_all) {
 199 
 200   f->do_ptr((void**)&_boolArrayKlassObj);
 201   f->do_ptr((void**)&_byteArrayKlassObj);
 202   f->do_ptr((void**)&_charArrayKlassObj);
 203   f->do_ptr((void**)&_intArrayKlassObj);
 204   f->do_ptr((void**)&_shortArrayKlassObj);
 205   f->do_ptr((void**)&_longArrayKlassObj);
 206   f->do_ptr((void**)&_singleArrayKlassObj);
 207   f->do_ptr((void**)&_doubleArrayKlassObj);
 208   f->do_ptr((void**)&_objectArrayKlassObj);
 209 
 210   {
 211     for (int i = 0; i < T_VOID+1; i++) {
 212       if (_typeArrayKlassObjs[i] != NULL) {
 213         assert(i >= T_BOOLEAN, "checking");
 214         f->do_ptr((void**)&_typeArrayKlassObjs[i]);
 215       } else if (do_all) {
 216         f->do_ptr((void**)&_typeArrayKlassObjs[i]);
 217       }
 218     }
 219   }
 220 
 221   f->do_ptr((void**)&_the_array_interfaces_array);
 222   f->do_ptr((void**)&_the_empty_int_array);
 223   f->do_ptr((void**)&_the_empty_short_array);
 224   f->do_ptr((void**)&_the_empty_method_array);
 225   f->do_ptr((void**)&_the_empty_klass_array);
 226   _finalizer_register_cache->serialize(f);
 227   _loader_addClass_cache->serialize(f);
 228   _reflect_invoke_cache->serialize(f);
 229   _pd_implies_cache->serialize(f);
 230 }
 231 
 232 void Universe::check_alignment(uintx size, uintx alignment, const char* name) {
 233   if (size < alignment || size % alignment != 0) {
 234     vm_exit_during_initialization(
 235       err_msg("Size of %s (" UINTX_FORMAT " bytes) must be aligned to " UINTX_FORMAT " bytes", name, size, alignment));
 236   }
 237 }
 238 
 239 void initialize_basic_type_klass(Klass* k, TRAPS) {
 240   Klass* ok = SystemDictionary::Object_klass();
 241   if (UseSharedSpaces) {
 242     assert(k->super() == ok, "u3");
 243     k->restore_unshareable_info(CHECK);
 244   } else {
 245     k->initialize_supers(ok, CHECK);
 246   }
 247   k->append_to_sibling_list();
 248 }
 249 
 250 void Universe::genesis(TRAPS) {
 251   ResourceMark rm;
 252 
 253   { FlagSetting fs(_bootstrapping, true);
 254 
 255     { MutexLocker mc(Compile_lock);
 256 
 257       // determine base vtable size; without that we cannot create the array klasses
 258       compute_base_vtable_size();
 259 
 260       if (!UseSharedSpaces) {
 261         _boolArrayKlassObj      = TypeArrayKlass::create_klass(T_BOOLEAN, sizeof(jboolean), CHECK);
 262         _charArrayKlassObj      = TypeArrayKlass::create_klass(T_CHAR,    sizeof(jchar),    CHECK);
 263         _singleArrayKlassObj    = TypeArrayKlass::create_klass(T_FLOAT,   sizeof(jfloat),   CHECK);
 264         _doubleArrayKlassObj    = TypeArrayKlass::create_klass(T_DOUBLE,  sizeof(jdouble),  CHECK);
 265         _byteArrayKlassObj      = TypeArrayKlass::create_klass(T_BYTE,    sizeof(jbyte),    CHECK);
 266         _shortArrayKlassObj     = TypeArrayKlass::create_klass(T_SHORT,   sizeof(jshort),   CHECK);
 267         _intArrayKlassObj       = TypeArrayKlass::create_klass(T_INT,     sizeof(jint),     CHECK);
 268         _longArrayKlassObj      = TypeArrayKlass::create_klass(T_LONG,    sizeof(jlong),    CHECK);
 269 
 270         _typeArrayKlassObjs[T_BOOLEAN] = _boolArrayKlassObj;
 271         _typeArrayKlassObjs[T_CHAR]    = _charArrayKlassObj;
 272         _typeArrayKlassObjs[T_FLOAT]   = _singleArrayKlassObj;
 273         _typeArrayKlassObjs[T_DOUBLE]  = _doubleArrayKlassObj;
 274         _typeArrayKlassObjs[T_BYTE]    = _byteArrayKlassObj;
 275         _typeArrayKlassObjs[T_SHORT]   = _shortArrayKlassObj;
 276         _typeArrayKlassObjs[T_INT]     = _intArrayKlassObj;
 277         _typeArrayKlassObjs[T_LONG]    = _longArrayKlassObj;
 278 
 279         ClassLoaderData* null_cld = ClassLoaderData::the_null_class_loader_data();
 280 
 281         _the_array_interfaces_array = MetadataFactory::new_array<Klass*>(null_cld, 2, NULL, CHECK);
 282         _the_empty_int_array        = MetadataFactory::new_array<int>(null_cld, 0, CHECK);
 283         _the_empty_short_array      = MetadataFactory::new_array<u2>(null_cld, 0, CHECK);
 284         _the_empty_method_array     = MetadataFactory::new_array<Method*>(null_cld, 0, CHECK);
 285         _the_empty_klass_array      = MetadataFactory::new_array<Klass*>(null_cld, 0, CHECK);
 286       }
 287     }
 288 
 289     vmSymbols::initialize(CHECK);
 290 
 291     SystemDictionary::initialize(CHECK);
 292 
 293     Klass* ok = SystemDictionary::Object_klass();
 294 
 295     _the_null_string            = StringTable::intern("null", CHECK);
 296     _the_min_jint_string       = StringTable::intern("-2147483648", CHECK);
 297 
 298     if (UseSharedSpaces) {
 299       // Verify shared interfaces array.
 300       assert(_the_array_interfaces_array->at(0) ==
 301              SystemDictionary::Cloneable_klass(), "u3");
 302       assert(_the_array_interfaces_array->at(1) ==
 303              SystemDictionary::Serializable_klass(), "u3");
 304     } else {
 305       // Set up shared interfaces array.  (Do this before supers are set up.)
 306       _the_array_interfaces_array->at_put(0, SystemDictionary::Cloneable_klass());
 307       _the_array_interfaces_array->at_put(1, SystemDictionary::Serializable_klass());
 308     }
 309 
 310     initialize_basic_type_klass(boolArrayKlassObj(), CHECK);
 311     initialize_basic_type_klass(charArrayKlassObj(), CHECK);
 312     initialize_basic_type_klass(singleArrayKlassObj(), CHECK);
 313     initialize_basic_type_klass(doubleArrayKlassObj(), CHECK);
 314     initialize_basic_type_klass(byteArrayKlassObj(), CHECK);
 315     initialize_basic_type_klass(shortArrayKlassObj(), CHECK);
 316     initialize_basic_type_klass(intArrayKlassObj(), CHECK);
 317     initialize_basic_type_klass(longArrayKlassObj(), CHECK);
 318   } // end of core bootstrapping
 319 
 320   // Maybe this could be lifted up now that object array can be initialized
 321   // during the bootstrapping.
 322 
 323   // OLD
 324   // Initialize _objectArrayKlass after core bootstraping to make
 325   // sure the super class is set up properly for _objectArrayKlass.
 326   // ---
 327   // NEW
 328   // Since some of the old system object arrays have been converted to
 329   // ordinary object arrays, _objectArrayKlass will be loaded when
 330   // SystemDictionary::initialize(CHECK); is run. See the extra check
 331   // for Object_klass_loaded in objArrayKlassKlass::allocate_objArray_klass_impl.
 332   _objectArrayKlassObj = InstanceKlass::
 333     cast(SystemDictionary::Object_klass())->array_klass(1, CHECK);
 334   // OLD
 335   // Add the class to the class hierarchy manually to make sure that
 336   // its vtable is initialized after core bootstrapping is completed.
 337   // ---
 338   // New
 339   // Have already been initialized.
 340   _objectArrayKlassObj->append_to_sibling_list();
 341 
 342   // Compute is_jdk version flags.
 343   // Only 1.3 or later has the java.lang.Shutdown class.
 344   // Only 1.4 or later has the java.lang.CharSequence interface.
 345   // Only 1.5 or later has the java.lang.management.MemoryUsage class.
 346   if (JDK_Version::is_partially_initialized()) {
 347     uint8_t jdk_version;
 348     Klass* k = SystemDictionary::resolve_or_null(
 349         vmSymbols::java_lang_management_MemoryUsage(), THREAD);
 350     CLEAR_PENDING_EXCEPTION; // ignore exceptions
 351     if (k == NULL) {
 352       k = SystemDictionary::resolve_or_null(
 353           vmSymbols::java_lang_CharSequence(), THREAD);
 354       CLEAR_PENDING_EXCEPTION; // ignore exceptions
 355       if (k == NULL) {
 356         k = SystemDictionary::resolve_or_null(
 357             vmSymbols::java_lang_Shutdown(), THREAD);
 358         CLEAR_PENDING_EXCEPTION; // ignore exceptions
 359         if (k == NULL) {
 360           jdk_version = 2;
 361         } else {
 362           jdk_version = 3;
 363         }
 364       } else {
 365         jdk_version = 4;
 366       }
 367     } else {
 368       jdk_version = 5;
 369     }
 370     JDK_Version::fully_initialize(jdk_version);
 371   }
 372 
 373   #ifdef ASSERT
 374   if (FullGCALot) {
 375     // Allocate an array of dummy objects.
 376     // We'd like these to be at the bottom of the old generation,
 377     // so that when we free one and then collect,
 378     // (almost) the whole heap moves
 379     // and we find out if we actually update all the oops correctly.
 380     // But we can't allocate directly in the old generation,
 381     // so we allocate wherever, and hope that the first collection
 382     // moves these objects to the bottom of the old generation.
 383     // We can allocate directly in the permanent generation, so we do.
 384     int size;
 385     if (UseConcMarkSweepGC) {
 386       warning("Using +FullGCALot with concurrent mark sweep gc "
 387               "will not force all objects to relocate");
 388       size = FullGCALotDummies;
 389     } else {
 390       size = FullGCALotDummies * 2;
 391     }
 392     objArrayOop    naked_array = oopFactory::new_objArray(SystemDictionary::Object_klass(), size, CHECK);
 393     objArrayHandle dummy_array(THREAD, naked_array);
 394     int i = 0;
 395     while (i < size) {
 396         // Allocate dummy in old generation
 397       oop dummy = InstanceKlass::cast(SystemDictionary::Object_klass())->allocate_instance(CHECK);
 398       dummy_array->obj_at_put(i++, dummy);
 399     }
 400     {
 401       // Only modify the global variable inside the mutex.
 402       // If we had a race to here, the other dummy_array instances
 403       // and their elements just get dropped on the floor, which is fine.
 404       MutexLocker ml(FullGCALot_lock);
 405       if (_fullgc_alot_dummy_array == NULL) {
 406         _fullgc_alot_dummy_array = dummy_array();
 407       }
 408     }
 409     assert(i == _fullgc_alot_dummy_array->length(), "just checking");
 410   }
 411   #endif
 412 
 413   // Initialize dependency array for null class loader
 414   ClassLoaderData::the_null_class_loader_data()->init_dependencies(CHECK);
 415 
 416 }
 417 
 418 // CDS support for patching vtables in metadata in the shared archive.
 419 // All types inherited from Metadata have vtables, but not types inherited
 420 // from MetaspaceObj, because the latter does not have virtual functions.
 421 // If the metadata type has a vtable, it cannot be shared in the read-only
 422 // section of the CDS archive, because the vtable pointer is patched.
 423 static inline void add_vtable(void** list, int* n, void* o, int count) {
 424   guarantee((*n) < count, "vtable list too small");
 425   void* vtable = dereference_vptr(o);
 426   assert(*(void**)(vtable) != NULL, "invalid vtable");
 427   list[(*n)++] = vtable;
 428 }
 429 
 430 void Universe::init_self_patching_vtbl_list(void** list, int count) {
 431   int n = 0;
 432   { InstanceKlass o;          add_vtable(list, &n, &o, count); }
 433   { InstanceClassLoaderKlass o; add_vtable(list, &n, &o, count); }
 434   { InstanceMirrorKlass o;    add_vtable(list, &n, &o, count); }
 435   { InstanceRefKlass o;       add_vtable(list, &n, &o, count); }
 436   { TypeArrayKlass o;         add_vtable(list, &n, &o, count); }
 437   { ObjArrayKlass o;          add_vtable(list, &n, &o, count); }
 438   { Method o;                 add_vtable(list, &n, &o, count); }
 439   { ConstantPool o;           add_vtable(list, &n, &o, count); }
 440 }
 441 
 442 void Universe::initialize_basic_type_mirrors(TRAPS) {
 443     assert(_int_mirror==NULL, "basic type mirrors already initialized");
 444     _int_mirror     =
 445       java_lang_Class::create_basic_type_mirror("int",    T_INT, CHECK);
 446     _float_mirror   =
 447       java_lang_Class::create_basic_type_mirror("float",  T_FLOAT,   CHECK);
 448     _double_mirror  =
 449       java_lang_Class::create_basic_type_mirror("double", T_DOUBLE,  CHECK);
 450     _byte_mirror    =
 451       java_lang_Class::create_basic_type_mirror("byte",   T_BYTE, CHECK);
 452     _bool_mirror    =
 453       java_lang_Class::create_basic_type_mirror("boolean",T_BOOLEAN, CHECK);
 454     _char_mirror    =
 455       java_lang_Class::create_basic_type_mirror("char",   T_CHAR, CHECK);
 456     _long_mirror    =
 457       java_lang_Class::create_basic_type_mirror("long",   T_LONG, CHECK);
 458     _short_mirror   =
 459       java_lang_Class::create_basic_type_mirror("short",  T_SHORT,   CHECK);
 460     _void_mirror    =
 461       java_lang_Class::create_basic_type_mirror("void",   T_VOID, CHECK);
 462 
 463     _mirrors[T_INT]     = _int_mirror;
 464     _mirrors[T_FLOAT]   = _float_mirror;
 465     _mirrors[T_DOUBLE]  = _double_mirror;
 466     _mirrors[T_BYTE]    = _byte_mirror;
 467     _mirrors[T_BOOLEAN] = _bool_mirror;
 468     _mirrors[T_CHAR]    = _char_mirror;
 469     _mirrors[T_LONG]    = _long_mirror;
 470     _mirrors[T_SHORT]   = _short_mirror;
 471     _mirrors[T_VOID]    = _void_mirror;
 472   //_mirrors[T_OBJECT]  = InstanceKlass::cast(_object_klass)->java_mirror();
 473   //_mirrors[T_ARRAY]   = InstanceKlass::cast(_object_klass)->java_mirror();
 474 }
 475 
 476 void Universe::fixup_mirrors(TRAPS) {
 477   // Bootstrap problem: all classes gets a mirror (java.lang.Class instance) assigned eagerly,
 478   // but we cannot do that for classes created before java.lang.Class is loaded. Here we simply
 479   // walk over permanent objects created so far (mostly classes) and fixup their mirrors. Note
 480   // that the number of objects allocated at this point is very small.
 481   assert(SystemDictionary::Class_klass_loaded(), "java.lang.Class should be loaded");
 482   HandleMark hm(THREAD);
 483   // Cache the start of the static fields
 484   InstanceMirrorKlass::init_offset_of_static_fields();
 485 
 486   GrowableArray <Klass*>* list = java_lang_Class::fixup_mirror_list();
 487   int list_length = list->length();
 488   for (int i = 0; i < list_length; i++) {
 489     Klass* k = list->at(i);
 490     assert(k->is_klass(), "List should only hold classes");
 491     EXCEPTION_MARK;
 492     KlassHandle kh(THREAD, k);
 493     java_lang_Class::fixup_mirror(kh, CATCH);
 494 }
 495   delete java_lang_Class::fixup_mirror_list();
 496   java_lang_Class::set_fixup_mirror_list(NULL);
 497 }
 498 
 499 static bool has_run_finalizers_on_exit = false;
 500 
 501 void Universe::run_finalizers_on_exit() {
 502   if (has_run_finalizers_on_exit) return;
 503   has_run_finalizers_on_exit = true;
 504 
 505   // Called on VM exit. This ought to be run in a separate thread.
 506   if (TraceReferenceGC) tty->print_cr("Callback to run finalizers on exit");
 507   {
 508     PRESERVE_EXCEPTION_MARK;
 509     KlassHandle finalizer_klass(THREAD, SystemDictionary::Finalizer_klass());
 510     JavaValue result(T_VOID);
 511     JavaCalls::call_static(
 512       &result,
 513       finalizer_klass,
 514       vmSymbols::run_finalizers_on_exit_name(),
 515       vmSymbols::void_method_signature(),
 516       THREAD
 517     );
 518     // Ignore any pending exceptions
 519     CLEAR_PENDING_EXCEPTION;
 520   }
 521 }
 522 
 523 
 524 // initialize_vtable could cause gc if
 525 // 1) we specified true to initialize_vtable and
 526 // 2) this ran after gc was enabled
 527 // In case those ever change we use handles for oops
 528 void Universe::reinitialize_vtable_of(KlassHandle k_h, TRAPS) {
 529   // init vtable of k and all subclasses
 530   Klass* ko = k_h();
 531   klassVtable* vt = ko->vtable();
 532   if (vt) vt->initialize_vtable(false, CHECK);
 533   if (ko->oop_is_instance()) {
 534     InstanceKlass* ik = (InstanceKlass*)ko;
 535     for (KlassHandle s_h(THREAD, ik->subklass());
 536          s_h() != NULL;
 537          s_h = KlassHandle(THREAD, s_h()->next_sibling())) {
 538       reinitialize_vtable_of(s_h, CHECK);
 539     }
 540   }
 541 }
 542 
 543 
 544 void initialize_itable_for_klass(Klass* k, TRAPS) {
 545   InstanceKlass::cast(k)->itable()->initialize_itable(false, CHECK);
 546 }
 547 
 548 
 549 void Universe::reinitialize_itables(TRAPS) {
 550   SystemDictionary::classes_do(initialize_itable_for_klass, CHECK);
 551 
 552 }
 553 
 554 
 555 bool Universe::on_page_boundary(void* addr) {
 556   return ((uintptr_t) addr) % os::vm_page_size() == 0;
 557 }
 558 
 559 
 560 bool Universe::should_fill_in_stack_trace(Handle throwable) {
 561   // never attempt to fill in the stack trace of preallocated errors that do not have
 562   // backtrace. These errors are kept alive forever and may be "re-used" when all
 563   // preallocated errors with backtrace have been consumed. Also need to avoid
 564   // a potential loop which could happen if an out of memory occurs when attempting
 565   // to allocate the backtrace.
 566   return ((throwable() != Universe::_out_of_memory_error_java_heap) &&
 567           (throwable() != Universe::_out_of_memory_error_metaspace)  &&
 568           (throwable() != Universe::_out_of_memory_error_class_metaspace)  &&
 569           (throwable() != Universe::_out_of_memory_error_array_size) &&
 570           (throwable() != Universe::_out_of_memory_error_gc_overhead_limit));
 571 }
 572 
 573 
 574 oop Universe::gen_out_of_memory_error(oop default_err) {
 575   // generate an out of memory error:
 576   // - if there is a preallocated error with backtrace available then return it wth
 577   //   a filled in stack trace.
 578   // - if there are no preallocated errors with backtrace available then return
 579   //   an error without backtrace.
 580   int next;
 581   if (_preallocated_out_of_memory_error_avail_count > 0) {
 582     next = (int)Atomic::add(-1, &_preallocated_out_of_memory_error_avail_count);
 583     assert(next < (int)PreallocatedOutOfMemoryErrorCount, "avail count is corrupt");
 584   } else {
 585     next = -1;
 586   }
 587   if (next < 0) {
 588     // all preallocated errors have been used.
 589     // return default
 590     return default_err;
 591   } else {
 592     // get the error object at the slot and set set it to NULL so that the
 593     // array isn't keeping it alive anymore.
 594     oop exc = preallocated_out_of_memory_errors()->obj_at(next);
 595     assert(exc != NULL, "slot has been used already");
 596     preallocated_out_of_memory_errors()->obj_at_put(next, NULL);
 597 
 598     // use the message from the default error
 599     oop msg = java_lang_Throwable::message(default_err);
 600     assert(msg != NULL, "no message");
 601     java_lang_Throwable::set_message(exc, msg);
 602 
 603     // populate the stack trace and return it.
 604     java_lang_Throwable::fill_in_stack_trace_of_preallocated_backtrace(exc);
 605     return exc;
 606   }
 607 }
 608 
 609 static intptr_t non_oop_bits = 0;
 610 
 611 void* Universe::non_oop_word() {
 612   // Neither the high bits nor the low bits of this value is allowed
 613   // to look like (respectively) the high or low bits of a real oop.
 614   //
 615   // High and low are CPU-specific notions, but low always includes
 616   // the low-order bit.  Since oops are always aligned at least mod 4,
 617   // setting the low-order bit will ensure that the low half of the
 618   // word will never look like that of a real oop.
 619   //
 620   // Using the OS-supplied non-memory-address word (usually 0 or -1)
 621   // will take care of the high bits, however many there are.
 622 
 623   if (non_oop_bits == 0) {
 624     non_oop_bits = (intptr_t)os::non_memory_address_word() | 1;
 625   }
 626 
 627   return (void*)non_oop_bits;
 628 }
 629 
 630 jint universe_init() {
 631   assert(!Universe::_fully_initialized, "called after initialize_vtables");
 632   guarantee(1 << LogHeapWordSize == sizeof(HeapWord),
 633          "LogHeapWordSize is incorrect.");
 634   guarantee(sizeof(oop) >= sizeof(HeapWord), "HeapWord larger than oop?");
 635   guarantee(sizeof(oop) % sizeof(HeapWord) == 0,
 636             "oop size is not not a multiple of HeapWord size");
 637   TraceTime timer("Genesis", TraceStartupTime);
 638   GC_locker::lock();  // do not allow gc during bootstrapping
 639   JavaClasses::compute_hard_coded_offsets();
 640 
 641   jint status = Universe::initialize_heap();
 642   if (status != JNI_OK) {
 643     return status;
 644   }
 645 
 646   // Create memory for metadata.  Must be after initializing heap for
 647   // DumpSharedSpaces.
 648   ClassLoaderData::init_null_class_loader_data();
 649 
 650   // We have a heap so create the Method* caches before
 651   // Metaspace::initialize_shared_spaces() tries to populate them.
 652   Universe::_finalizer_register_cache = new LatestMethodOopCache();
 653   Universe::_loader_addClass_cache    = new LatestMethodOopCache();
 654   Universe::_pd_implies_cache         = new LatestMethodOopCache();
 655   Universe::_reflect_invoke_cache     = new ActiveMethodOopsCache();
 656 
 657   if (UseSharedSpaces) {
 658     // Read the data structures supporting the shared spaces (shared
 659     // system dictionary, symbol table, etc.).  After that, access to
 660     // the file (other than the mapped regions) is no longer needed, and
 661     // the file is closed. Closing the file does not affect the
 662     // currently mapped regions.
 663     MetaspaceShared::initialize_shared_spaces();
 664     StringTable::create_table();
 665   } else {
 666     SymbolTable::create_table();
 667     StringTable::create_table();
 668     ClassLoader::create_package_info_table();
 669   }
 670 
 671   return JNI_OK;
 672 }
 673 
 674 // Choose the heap base address and oop encoding mode
 675 // when compressed oops are used:
 676 // Unscaled  - Use 32-bits oops without encoding when
 677 //     NarrowOopHeapBaseMin + heap_size < 4Gb
 678 // ZeroBased - Use zero based compressed oops with encoding when
 679 //     NarrowOopHeapBaseMin + heap_size < 32Gb
 680 // HeapBased - Use compressed oops with heap base + encoding.
 681 
 682 // 4Gb
 683 static const uint64_t NarrowOopHeapMax = (uint64_t(max_juint) + 1);
 684 // 32Gb
 685 // OopEncodingHeapMax == NarrowOopHeapMax << LogMinObjAlignmentInBytes;
 686 
 687 char* Universe::preferred_heap_base(size_t heap_size, NARROW_OOP_MODE mode) {
 688   size_t base = 0;
 689 #ifdef _LP64
 690   if (UseCompressedOops) {
 691     assert(mode == UnscaledNarrowOop  ||
 692            mode == ZeroBasedNarrowOop ||
 693            mode == HeapBasedNarrowOop, "mode is invalid");
 694     const size_t total_size = heap_size + HeapBaseMinAddress;
 695     // Return specified base for the first request.
 696     if (!FLAG_IS_DEFAULT(HeapBaseMinAddress) && (mode == UnscaledNarrowOop)) {
 697       base = HeapBaseMinAddress;
 698 
 699     // If the total size and the metaspace size are small enough to allow
 700     // UnscaledNarrowOop then just use UnscaledNarrowOop.
 701     } else if ((total_size <= OopEncodingHeapMax) && (mode != HeapBasedNarrowOop) &&
 702         (!UseCompressedKlassPointers ||
 703           (((OopEncodingHeapMax - heap_size) + Universe::class_metaspace_size()) <= KlassEncodingMetaspaceMax))) {
 704       // We don't need to check the metaspace size here because it is always smaller
 705       // than total_size.
 706       if ((total_size <= NarrowOopHeapMax) && (mode == UnscaledNarrowOop) &&
 707           (Universe::narrow_oop_shift() == 0)) {
 708         // Use 32-bits oops without encoding and
 709         // place heap's top on the 4Gb boundary
 710         base = (NarrowOopHeapMax - heap_size);
 711       } else {
 712         // Can't reserve with NarrowOopShift == 0
 713         Universe::set_narrow_oop_shift(LogMinObjAlignmentInBytes);
 714         if (mode == UnscaledNarrowOop ||
 715             mode == ZeroBasedNarrowOop && total_size <= NarrowOopHeapMax) {
 716           // Use zero based compressed oops with encoding and
 717           // place heap's top on the 32Gb boundary in case
 718           // total_size > 4Gb or failed to reserve below 4Gb.
 719           base = (OopEncodingHeapMax - heap_size);
 720         }
 721       }
 722 
 723     // See if ZeroBaseNarrowOop encoding will work for a heap based at
 724     // (KlassEncodingMetaspaceMax - class_metaspace_size()).
 725     } else if (UseCompressedKlassPointers && (mode != HeapBasedNarrowOop) &&
 726         (Universe::class_metaspace_size() + HeapBaseMinAddress <= KlassEncodingMetaspaceMax) &&
 727         (KlassEncodingMetaspaceMax + heap_size - Universe::class_metaspace_size() <= OopEncodingHeapMax)) {
 728       base = (KlassEncodingMetaspaceMax - Universe::class_metaspace_size());
 729     } else {
 730       // UnscaledNarrowOop encoding didn't work, and no base was found for ZeroBasedOops or
 731       // HeapBasedNarrowOop encoding was requested.  So, can't reserve below 32Gb.
 732       Universe::set_narrow_oop_shift(LogMinObjAlignmentInBytes);
 733     }
 734 
 735     // Set narrow_oop_base and narrow_oop_use_implicit_null_checks
 736     // used in ReservedHeapSpace() constructors.
 737     // The final values will be set in initialize_heap() below.
 738     if ((base != 0) && ((base + heap_size) <= OopEncodingHeapMax) &&
 739         (!UseCompressedKlassPointers || (base + Universe::class_metaspace_size()) <= KlassEncodingMetaspaceMax)) {
 740       // Use zero based compressed oops
 741       Universe::set_narrow_oop_base(NULL);
 742       // Don't need guard page for implicit checks in indexed
 743       // addressing mode with zero based Compressed Oops.
 744       Universe::set_narrow_oop_use_implicit_null_checks(true);
 745     } else {
 746       // Set to a non-NULL value so the ReservedSpace ctor computes
 747       // the correct no-access prefix.
 748       // The final value will be set in initialize_heap() below.
 749       Universe::set_narrow_oop_base((address)NarrowOopHeapMax);
 750 #ifdef _WIN64
 751       if (UseLargePages) {
 752         // Cannot allocate guard pages for implicit checks in indexed
 753         // addressing mode when large pages are specified on windows.
 754         Universe::set_narrow_oop_use_implicit_null_checks(false);
 755       }
 756 #endif //  _WIN64
 757     }
 758   }
 759 #endif
 760   return (char*)base; // also return NULL (don't care) for 32-bit VM
 761 }
 762 
 763 jint Universe::initialize_heap() {
 764 
 765   if (UseParallelGC) {
 766 #if INCLUDE_ALL_GCS
 767     Universe::_collectedHeap = new ParallelScavengeHeap();
 768 #else  // INCLUDE_ALL_GCS
 769     fatal("UseParallelGC not supported in this VM.");
 770 #endif // INCLUDE_ALL_GCS
 771 
 772   } else if (UseG1GC) {
 773 #if INCLUDE_ALL_GCS
 774     G1CollectorPolicy* g1p = new G1CollectorPolicy();
 775     G1CollectedHeap* g1h = new G1CollectedHeap(g1p);
 776     Universe::_collectedHeap = g1h;
 777 #else  // INCLUDE_ALL_GCS
 778     fatal("UseG1GC not supported in java kernel vm.");
 779 #endif // INCLUDE_ALL_GCS
 780 
 781   } else {
 782     GenCollectorPolicy *gc_policy;
 783 
 784     if (UseSerialGC) {
 785       gc_policy = new MarkSweepPolicy();
 786     } else if (UseConcMarkSweepGC) {
 787 #if INCLUDE_ALL_GCS
 788       if (UseAdaptiveSizePolicy) {
 789         gc_policy = new ASConcurrentMarkSweepPolicy();
 790       } else {
 791         gc_policy = new ConcurrentMarkSweepPolicy();
 792       }
 793 #else  // INCLUDE_ALL_GCS
 794     fatal("UseConcMarkSweepGC not supported in this VM.");
 795 #endif // INCLUDE_ALL_GCS
 796     } else { // default old generation
 797       gc_policy = new MarkSweepPolicy();
 798     }
 799 
 800     Universe::_collectedHeap = new GenCollectedHeap(gc_policy);
 801   }
 802 
 803   jint status = Universe::heap()->initialize();
 804   if (status != JNI_OK) {
 805     return status;
 806   }
 807 
 808 #ifdef _LP64
 809   if (UseCompressedOops) {
 810     // Subtract a page because something can get allocated at heap base.
 811     // This also makes implicit null checking work, because the
 812     // memory+1 page below heap_base needs to cause a signal.
 813     // See needs_explicit_null_check.
 814     // Only set the heap base for compressed oops because it indicates
 815     // compressed oops for pstack code.
 816     bool verbose = PrintCompressedOopsMode || (PrintMiscellaneous && Verbose);
 817     if (verbose) {
 818       tty->cr();
 819       tty->print("heap address: " PTR_FORMAT ", size: " SIZE_FORMAT " MB",
 820                  Universe::heap()->base(), Universe::heap()->reserved_region().byte_size()/M);
 821     }
 822     if (((uint64_t)Universe::heap()->reserved_region().end() > OopEncodingHeapMax) ||
 823         (UseCompressedKlassPointers &&
 824         ((uint64_t)Universe::heap()->base() + Universe::class_metaspace_size() > KlassEncodingMetaspaceMax))) {
 825       // Can't reserve heap below 32Gb.
 826       // keep the Universe::narrow_oop_base() set in Universe::reserve_heap()
 827       Universe::set_narrow_oop_shift(LogMinObjAlignmentInBytes);
 828       if (verbose) {
 829         tty->print(", %s: "PTR_FORMAT,
 830             narrow_oop_mode_to_string(HeapBasedNarrowOop),
 831             Universe::narrow_oop_base());
 832       }
 833     } else {
 834       Universe::set_narrow_oop_base(0);
 835       if (verbose) {
 836         tty->print(", %s", narrow_oop_mode_to_string(ZeroBasedNarrowOop));
 837       }
 838 #ifdef _WIN64
 839       if (!Universe::narrow_oop_use_implicit_null_checks()) {
 840         // Don't need guard page for implicit checks in indexed addressing
 841         // mode with zero based Compressed Oops.
 842         Universe::set_narrow_oop_use_implicit_null_checks(true);
 843       }
 844 #endif //  _WIN64
 845       if((uint64_t)Universe::heap()->reserved_region().end() > NarrowOopHeapMax) {
 846         // Can't reserve heap below 4Gb.
 847         Universe::set_narrow_oop_shift(LogMinObjAlignmentInBytes);
 848       } else {
 849         Universe::set_narrow_oop_shift(0);
 850         if (verbose) {
 851           tty->print(", %s", narrow_oop_mode_to_string(UnscaledNarrowOop));
 852         }
 853       }
 854     }
 855     if (verbose) {
 856       tty->cr();
 857       tty->cr();
 858     }
 859     if (UseCompressedKlassPointers) {
 860       Universe::set_narrow_klass_base(Universe::narrow_oop_base());
 861       Universe::set_narrow_klass_shift(MIN2(Universe::narrow_oop_shift(), LogKlassAlignmentInBytes));
 862     }
 863     Universe::set_narrow_ptrs_base(Universe::narrow_oop_base());
 864   }
 865   // Universe::narrow_oop_base() is one page below the metaspace
 866   // base. The actual metaspace base depends on alignment constraints
 867   // so we don't know its exact location here.
 868   assert((intptr_t)Universe::narrow_oop_base() <= (intptr_t)(Universe::heap()->base() - os::vm_page_size() - ClassMetaspaceSize) ||
 869          Universe::narrow_oop_base() == NULL, "invalid value");
 870   assert(Universe::narrow_oop_shift() == LogMinObjAlignmentInBytes ||
 871          Universe::narrow_oop_shift() == 0, "invalid value");
 872 #endif
 873 
 874   // We will never reach the CATCH below since Exceptions::_throw will cause
 875   // the VM to exit if an exception is thrown during initialization
 876 
 877   if (UseTLAB) {
 878     assert(Universe::heap()->supports_tlab_allocation(),
 879            "Should support thread-local allocation buffers");
 880     ThreadLocalAllocBuffer::startup_initialization();
 881   }
 882   return JNI_OK;
 883 }
 884 
 885 
 886 // Reserve the Java heap, which is now the same for all GCs.
 887 ReservedSpace Universe::reserve_heap(size_t heap_size, size_t alignment) {
 888   // Add in the class metaspace area so the classes in the headers can
 889   // be compressed the same as instances.
 890   // Need to round class space size up because it's below the heap and
 891   // the actual alignment depends on its size.
 892   Universe::set_class_metaspace_size(align_size_up(ClassMetaspaceSize, alignment));
 893   size_t total_reserved = align_size_up(heap_size + Universe::class_metaspace_size(), alignment);
 894   assert(!UseCompressedOops || (total_reserved <= (OopEncodingHeapMax - os::vm_page_size())),
 895       "heap size is too big for compressed oops");
 896   char* addr = Universe::preferred_heap_base(total_reserved, Universe::UnscaledNarrowOop);
 897 
 898   ReservedHeapSpace total_rs(total_reserved, alignment, UseLargePages, addr);
 899 
 900   if (UseCompressedOops) {
 901     if (addr != NULL && !total_rs.is_reserved()) {
 902       // Failed to reserve at specified address - the requested memory
 903       // region is taken already, for example, by 'java' launcher.
 904       // Try again to reserver heap higher.
 905       addr = Universe::preferred_heap_base(total_reserved, Universe::ZeroBasedNarrowOop);
 906 
 907       ReservedHeapSpace total_rs0(total_reserved, alignment,
 908                                   UseLargePages, addr);
 909 
 910       if (addr != NULL && !total_rs0.is_reserved()) {
 911         // Failed to reserve at specified address again - give up.
 912         addr = Universe::preferred_heap_base(total_reserved, Universe::HeapBasedNarrowOop);
 913         assert(addr == NULL, "");
 914 
 915         ReservedHeapSpace total_rs1(total_reserved, alignment,
 916                                     UseLargePages, addr);
 917         total_rs = total_rs1;
 918       } else {
 919         total_rs = total_rs0;
 920       }
 921     }
 922   }
 923 
 924   if (!total_rs.is_reserved()) {
 925     vm_exit_during_initialization(err_msg("Could not reserve enough space for " SIZE_FORMAT "KB object heap", total_reserved/K));
 926     return total_rs;
 927   }
 928 
 929   // Split the reserved space into main Java heap and a space for
 930   // classes so that they can be compressed using the same algorithm
 931   // as compressed oops. If compress oops and compress klass ptrs are
 932   // used we need the meta space first: if the alignment used for
 933   // compressed oops is greater than the one used for compressed klass
 934   // ptrs, a metadata space on top of the heap could become
 935   // unreachable.
 936   ReservedSpace class_rs = total_rs.first_part(Universe::class_metaspace_size());
 937   ReservedSpace heap_rs = total_rs.last_part(Universe::class_metaspace_size(), alignment);
 938   Metaspace::initialize_class_space(class_rs);
 939 
 940   if (UseCompressedOops) {
 941     // Universe::initialize_heap() will reset this to NULL if unscaled
 942     // or zero-based narrow oops are actually used.
 943     address base = (address)(total_rs.base() - os::vm_page_size());
 944     Universe::set_narrow_oop_base(base);
 945   }
 946   return heap_rs;
 947 }
 948 
 949 
 950 // It's the caller's repsonsibility to ensure glitch-freedom
 951 // (if required).
 952 void Universe::update_heap_info_at_gc() {
 953   _heap_capacity_at_last_gc = heap()->capacity();
 954   _heap_used_at_last_gc     = heap()->used();
 955 }
 956 
 957 
 958 const char* Universe::narrow_oop_mode_to_string(Universe::NARROW_OOP_MODE mode) {
 959   switch (mode) {
 960     case UnscaledNarrowOop:
 961       return "32-bits Oops";
 962     case ZeroBasedNarrowOop:
 963       return "zero based Compressed Oops";
 964     case HeapBasedNarrowOop:
 965       return "Compressed Oops with base";
 966   }
 967 
 968   ShouldNotReachHere();
 969   return "";
 970 }
 971 
 972 
 973 Universe::NARROW_OOP_MODE Universe::narrow_oop_mode() {
 974   if (narrow_oop_base() != 0) {
 975     return HeapBasedNarrowOop;
 976   }
 977 
 978   if (narrow_oop_shift() != 0) {
 979     return ZeroBasedNarrowOop;
 980   }
 981 
 982   return UnscaledNarrowOop;
 983 }
 984 
 985 
 986 void universe2_init() {
 987   EXCEPTION_MARK;
 988   Universe::genesis(CATCH);
 989 }
 990 
 991 
 992 // This function is defined in JVM.cpp
 993 extern void initialize_converter_functions();
 994 
 995 bool universe_post_init() {
 996   assert(!is_init_completed(), "Error: initialization not yet completed!");
 997   Universe::_fully_initialized = true;
 998   EXCEPTION_MARK;
 999   { ResourceMark rm;
1000     Interpreter::initialize();      // needed for interpreter entry points
1001     if (!UseSharedSpaces) {
1002       HandleMark hm(THREAD);
1003       KlassHandle ok_h(THREAD, SystemDictionary::Object_klass());
1004       Universe::reinitialize_vtable_of(ok_h, CHECK_false);
1005       Universe::reinitialize_itables(CHECK_false);
1006     }
1007   }
1008 
1009   HandleMark hm(THREAD);
1010   Klass* k;
1011   instanceKlassHandle k_h;
1012     // Setup preallocated empty java.lang.Class array
1013     Universe::_the_empty_class_klass_array = oopFactory::new_objArray(SystemDictionary::Class_klass(), 0, CHECK_false);
1014 
1015     // Setup preallocated OutOfMemoryError errors
1016     k = SystemDictionary::resolve_or_fail(vmSymbols::java_lang_OutOfMemoryError(), true, CHECK_false);
1017     k_h = instanceKlassHandle(THREAD, k);
1018     Universe::_out_of_memory_error_java_heap = k_h->allocate_instance(CHECK_false);
1019     Universe::_out_of_memory_error_metaspace = k_h->allocate_instance(CHECK_false);
1020     Universe::_out_of_memory_error_class_metaspace = k_h->allocate_instance(CHECK_false);
1021     Universe::_out_of_memory_error_array_size = k_h->allocate_instance(CHECK_false);
1022     Universe::_out_of_memory_error_gc_overhead_limit =
1023       k_h->allocate_instance(CHECK_false);
1024 
1025     // Setup preallocated NullPointerException
1026     // (this is currently used for a cheap & dirty solution in compiler exception handling)
1027     k = SystemDictionary::resolve_or_fail(vmSymbols::java_lang_NullPointerException(), true, CHECK_false);
1028     Universe::_null_ptr_exception_instance = InstanceKlass::cast(k)->allocate_instance(CHECK_false);
1029     // Setup preallocated ArithmeticException
1030     // (this is currently used for a cheap & dirty solution in compiler exception handling)
1031     k = SystemDictionary::resolve_or_fail(vmSymbols::java_lang_ArithmeticException(), true, CHECK_false);
1032     Universe::_arithmetic_exception_instance = InstanceKlass::cast(k)->allocate_instance(CHECK_false);
1033     // Virtual Machine Error for when we get into a situation we can't resolve
1034     k = SystemDictionary::resolve_or_fail(
1035       vmSymbols::java_lang_VirtualMachineError(), true, CHECK_false);
1036     bool linked = InstanceKlass::cast(k)->link_class_or_fail(CHECK_false);
1037     if (!linked) {
1038       tty->print_cr("Unable to link/verify VirtualMachineError class");
1039       return false; // initialization failed
1040     }
1041     Universe::_virtual_machine_error_instance =
1042       InstanceKlass::cast(k)->allocate_instance(CHECK_false);
1043 
1044     Universe::_vm_exception               = InstanceKlass::cast(k)->allocate_instance(CHECK_false);
1045 
1046   if (!DumpSharedSpaces) {
1047     // These are the only Java fields that are currently set during shared space dumping.
1048     // We prefer to not handle this generally, so we always reinitialize these detail messages.
1049     Handle msg = java_lang_String::create_from_str("Java heap space", CHECK_false);
1050     java_lang_Throwable::set_message(Universe::_out_of_memory_error_java_heap, msg());
1051 
1052     msg = java_lang_String::create_from_str("Metadata space", CHECK_false);
1053     java_lang_Throwable::set_message(Universe::_out_of_memory_error_metaspace, msg());
1054     msg = java_lang_String::create_from_str("Class Metadata space", CHECK_false);
1055     java_lang_Throwable::set_message(Universe::_out_of_memory_error_class_metaspace, msg());
1056 
1057     msg = java_lang_String::create_from_str("Requested array size exceeds VM limit", CHECK_false);
1058     java_lang_Throwable::set_message(Universe::_out_of_memory_error_array_size, msg());
1059 
1060     msg = java_lang_String::create_from_str("GC overhead limit exceeded", CHECK_false);
1061     java_lang_Throwable::set_message(Universe::_out_of_memory_error_gc_overhead_limit, msg());
1062 
1063     msg = java_lang_String::create_from_str("/ by zero", CHECK_false);
1064     java_lang_Throwable::set_message(Universe::_arithmetic_exception_instance, msg());
1065 
1066     // Setup the array of errors that have preallocated backtrace
1067     k = Universe::_out_of_memory_error_java_heap->klass();
1068     assert(k->name() == vmSymbols::java_lang_OutOfMemoryError(), "should be out of memory error");
1069     k_h = instanceKlassHandle(THREAD, k);
1070 
1071     int len = (StackTraceInThrowable) ? (int)PreallocatedOutOfMemoryErrorCount : 0;
1072     Universe::_preallocated_out_of_memory_error_array = oopFactory::new_objArray(k_h(), len, CHECK_false);
1073     for (int i=0; i<len; i++) {
1074       oop err = k_h->allocate_instance(CHECK_false);
1075       Handle err_h = Handle(THREAD, err);
1076       java_lang_Throwable::allocate_backtrace(err_h, CHECK_false);
1077       Universe::preallocated_out_of_memory_errors()->obj_at_put(i, err_h());
1078     }
1079     Universe::_preallocated_out_of_memory_error_avail_count = (jint)len;
1080   }
1081 
1082 
1083   // Setup static method for registering finalizers
1084   // The finalizer klass must be linked before looking up the method, in
1085   // case it needs to get rewritten.
1086   InstanceKlass::cast(SystemDictionary::Finalizer_klass())->link_class(CHECK_false);
1087   Method* m = InstanceKlass::cast(SystemDictionary::Finalizer_klass())->find_method(
1088                                   vmSymbols::register_method_name(),
1089                                   vmSymbols::register_method_signature());
1090   if (m == NULL || !m->is_static()) {
1091     THROW_MSG_(vmSymbols::java_lang_NoSuchMethodException(),
1092       "java.lang.ref.Finalizer.register", false);
1093   }
1094   Universe::_finalizer_register_cache->init(
1095     SystemDictionary::Finalizer_klass(), m, CHECK_false);
1096 
1097   // Resolve on first use and initialize class.
1098   // Note: No race-condition here, since a resolve will always return the same result
1099 
1100   // Setup method for security checks
1101   k = SystemDictionary::resolve_or_fail(vmSymbols::java_lang_reflect_Method(), true, CHECK_false);
1102   k_h = instanceKlassHandle(THREAD, k);
1103   k_h->link_class(CHECK_false);
1104   m = k_h->find_method(vmSymbols::invoke_name(), vmSymbols::object_object_array_object_signature());
1105   if (m == NULL || m->is_static()) {
1106     THROW_MSG_(vmSymbols::java_lang_NoSuchMethodException(),
1107       "java.lang.reflect.Method.invoke", false);
1108   }
1109   Universe::_reflect_invoke_cache->init(k_h(), m, CHECK_false);
1110 
1111   // Setup method for registering loaded classes in class loader vector
1112   InstanceKlass::cast(SystemDictionary::ClassLoader_klass())->link_class(CHECK_false);
1113   m = InstanceKlass::cast(SystemDictionary::ClassLoader_klass())->find_method(vmSymbols::addClass_name(), vmSymbols::class_void_signature());
1114   if (m == NULL || m->is_static()) {
1115     THROW_MSG_(vmSymbols::java_lang_NoSuchMethodException(),
1116       "java.lang.ClassLoader.addClass", false);
1117   }
1118   Universe::_loader_addClass_cache->init(
1119     SystemDictionary::ClassLoader_klass(), m, CHECK_false);
1120 
1121   // Setup method for checking protection domain
1122   InstanceKlass::cast(SystemDictionary::ProtectionDomain_klass())->link_class(CHECK_false);
1123   m = InstanceKlass::cast(SystemDictionary::ProtectionDomain_klass())->
1124             find_method(vmSymbols::impliesCreateAccessControlContext_name(),
1125                         vmSymbols::void_boolean_signature());
1126   // Allow NULL which should only happen with bootstrapping.
1127   if (m != NULL) {
1128     if (m->is_static()) {
1129       // NoSuchMethodException doesn't actually work because it tries to run the
1130       // <init> function before java_lang_Class is linked. Print error and exit.
1131       tty->print_cr("ProtectionDomain.impliesCreateAccessControlContext() has the wrong linkage");
1132       return false; // initialization failed
1133     }
1134     Universe::_pd_implies_cache->init(
1135       SystemDictionary::ProtectionDomain_klass(), m, CHECK_false);;
1136   }
1137 
1138   // The folowing is initializing converter functions for serialization in
1139   // JVM.cpp. If we clean up the StrictMath code above we may want to find
1140   // a better solution for this as well.
1141   initialize_converter_functions();
1142 
1143   // This needs to be done before the first scavenge/gc, since
1144   // it's an input to soft ref clearing policy.
1145   {
1146     MutexLocker x(Heap_lock);
1147     Universe::update_heap_info_at_gc();
1148   }
1149 
1150   // ("weak") refs processing infrastructure initialization
1151   Universe::heap()->post_initialize();
1152 
1153   // Initialize performance counters for metaspaces
1154   MetaspaceCounters::initialize_performance_counters();
1155   MemoryService::add_metaspace_memory_pools();
1156 
1157   GC_locker::unlock();  // allow gc after bootstrapping
1158 
1159   MemoryService::set_universe_heap(Universe::_collectedHeap);
1160   return true;
1161 }
1162 
1163 
1164 void Universe::compute_base_vtable_size() {
1165   _base_vtable_size = ClassLoader::compute_Object_vtable();
1166 }
1167 
1168 
1169 // %%% The Universe::flush_foo methods belong in CodeCache.
1170 
1171 // Flushes compiled methods dependent on dependee.
1172 void Universe::flush_dependents_on(instanceKlassHandle dependee) {
1173   assert_lock_strong(Compile_lock);
1174 
1175   if (CodeCache::number_of_nmethods_with_dependencies() == 0) return;
1176 
1177   // CodeCache can only be updated by a thread_in_VM and they will all be
1178   // stopped dring the safepoint so CodeCache will be safe to update without
1179   // holding the CodeCache_lock.
1180 
1181   KlassDepChange changes(dependee);
1182 
1183   // Compute the dependent nmethods
1184   if (CodeCache::mark_for_deoptimization(changes) > 0) {
1185     // At least one nmethod has been marked for deoptimization
1186     VM_Deoptimize op;
1187     VMThread::execute(&op);
1188   }
1189 }
1190 
1191 // Flushes compiled methods dependent on a particular CallSite
1192 // instance when its target is different than the given MethodHandle.
1193 void Universe::flush_dependents_on(Handle call_site, Handle method_handle) {
1194   assert_lock_strong(Compile_lock);
1195 
1196   if (CodeCache::number_of_nmethods_with_dependencies() == 0) return;
1197 
1198   // CodeCache can only be updated by a thread_in_VM and they will all be
1199   // stopped dring the safepoint so CodeCache will be safe to update without
1200   // holding the CodeCache_lock.
1201 
1202   CallSiteDepChange changes(call_site(), method_handle());
1203 
1204   // Compute the dependent nmethods that have a reference to a
1205   // CallSite object.  We use InstanceKlass::mark_dependent_nmethod
1206   // directly instead of CodeCache::mark_for_deoptimization because we
1207   // want dependents on the call site class only not all classes in
1208   // the ContextStream.
1209   int marked = 0;
1210   {
1211     MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
1212     InstanceKlass* call_site_klass = InstanceKlass::cast(call_site->klass());
1213     marked = call_site_klass->mark_dependent_nmethods(changes);
1214   }
1215   if (marked > 0) {
1216     // At least one nmethod has been marked for deoptimization
1217     VM_Deoptimize op;
1218     VMThread::execute(&op);
1219   }
1220 }
1221 
1222 #ifdef HOTSWAP
1223 // Flushes compiled methods dependent on dependee in the evolutionary sense
1224 void Universe::flush_evol_dependents_on(instanceKlassHandle ev_k_h) {
1225   // --- Compile_lock is not held. However we are at a safepoint.
1226   assert_locked_or_safepoint(Compile_lock);
1227   if (CodeCache::number_of_nmethods_with_dependencies() == 0) return;
1228 
1229   // CodeCache can only be updated by a thread_in_VM and they will all be
1230   // stopped dring the safepoint so CodeCache will be safe to update without
1231   // holding the CodeCache_lock.
1232 
1233   // Compute the dependent nmethods
1234   if (CodeCache::mark_for_evol_deoptimization(ev_k_h) > 0) {
1235     // At least one nmethod has been marked for deoptimization
1236 
1237     // All this already happens inside a VM_Operation, so we'll do all the work here.
1238     // Stuff copied from VM_Deoptimize and modified slightly.
1239 
1240     // We do not want any GCs to happen while we are in the middle of this VM operation
1241     ResourceMark rm;
1242     DeoptimizationMarker dm;
1243 
1244     // Deoptimize all activations depending on marked nmethods
1245     Deoptimization::deoptimize_dependents();
1246 
1247     // Make the dependent methods not entrant (in VM_Deoptimize they are made zombies)
1248     CodeCache::make_marked_nmethods_not_entrant();
1249   }
1250 }
1251 #endif // HOTSWAP
1252 
1253 
1254 // Flushes compiled methods dependent on dependee
1255 void Universe::flush_dependents_on_method(methodHandle m_h) {
1256   // --- Compile_lock is not held. However we are at a safepoint.
1257   assert_locked_or_safepoint(Compile_lock);
1258 
1259   // CodeCache can only be updated by a thread_in_VM and they will all be
1260   // stopped dring the safepoint so CodeCache will be safe to update without
1261   // holding the CodeCache_lock.
1262 
1263   // Compute the dependent nmethods
1264   if (CodeCache::mark_for_deoptimization(m_h()) > 0) {
1265     // At least one nmethod has been marked for deoptimization
1266 
1267     // All this already happens inside a VM_Operation, so we'll do all the work here.
1268     // Stuff copied from VM_Deoptimize and modified slightly.
1269 
1270     // We do not want any GCs to happen while we are in the middle of this VM operation
1271     ResourceMark rm;
1272     DeoptimizationMarker dm;
1273 
1274     // Deoptimize all activations depending on marked nmethods
1275     Deoptimization::deoptimize_dependents();
1276 
1277     // Make the dependent methods not entrant (in VM_Deoptimize they are made zombies)
1278     CodeCache::make_marked_nmethods_not_entrant();
1279   }
1280 }
1281 
1282 void Universe::print() {
1283   print_on(gclog_or_tty);
1284 }
1285 
1286 void Universe::print_on(outputStream* st, bool extended) {
1287   st->print_cr("Heap");
1288   if (!extended) {
1289     heap()->print_on(st);
1290   } else {
1291     heap()->print_extended_on(st);
1292   }
1293 }
1294 
1295 void Universe::print_heap_at_SIGBREAK() {
1296   if (PrintHeapAtSIGBREAK) {
1297     MutexLocker hl(Heap_lock);
1298     print_on(tty);
1299     tty->cr();
1300     tty->flush();
1301   }
1302 }
1303 
1304 void Universe::print_heap_before_gc(outputStream* st, bool ignore_extended) {
1305   st->print_cr("{Heap before GC invocations=%u (full %u):",
1306                heap()->total_collections(),
1307                heap()->total_full_collections());
1308   if (!PrintHeapAtGCExtended || ignore_extended) {
1309     heap()->print_on(st);
1310   } else {
1311     heap()->print_extended_on(st);
1312   }
1313 }
1314 
1315 void Universe::print_heap_after_gc(outputStream* st, bool ignore_extended) {
1316   st->print_cr("Heap after GC invocations=%u (full %u):",
1317                heap()->total_collections(),
1318                heap()->total_full_collections());
1319   if (!PrintHeapAtGCExtended || ignore_extended) {
1320     heap()->print_on(st);
1321   } else {
1322     heap()->print_extended_on(st);
1323   }
1324   st->print_cr("}");
1325 }
1326 
1327 void Universe::verify(VerifyOption option, const char* prefix, bool silent) {
1328   // The use of _verify_in_progress is a temporary work around for
1329   // 6320749.  Don't bother with a creating a class to set and clear
1330   // it since it is only used in this method and the control flow is
1331   // straight forward.
1332   _verify_in_progress = true;
1333 
1334   COMPILER2_PRESENT(
1335     assert(!DerivedPointerTable::is_active(),
1336          "DPT should not be active during verification "
1337          "(of thread stacks below)");
1338   )
1339 
1340   ResourceMark rm;
1341   HandleMark hm;  // Handles created during verification can be zapped
1342   _verify_count++;
1343 
1344   if (!silent) gclog_or_tty->print(prefix);
1345   if (!silent) gclog_or_tty->print("[Verifying ");
1346   if (!silent) gclog_or_tty->print("threads ");
1347   Threads::verify();
1348   if (!silent) gclog_or_tty->print("heap ");
1349   heap()->verify(silent, option);
1350   if (!silent) gclog_or_tty->print("syms ");
1351   SymbolTable::verify();
1352   if (!silent) gclog_or_tty->print("strs ");
1353   StringTable::verify();
1354   {
1355     MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
1356     if (!silent) gclog_or_tty->print("zone ");
1357     CodeCache::verify();
1358   }
1359   if (!silent) gclog_or_tty->print("dict ");
1360   SystemDictionary::verify();
1361 #ifndef PRODUCT
1362   if (!silent) gclog_or_tty->print("cldg ");
1363   ClassLoaderDataGraph::verify();
1364 #endif
1365   if (!silent) gclog_or_tty->print("metaspace chunks ");
1366   MetaspaceAux::verify_free_chunks();
1367   if (!silent) gclog_or_tty->print("hand ");
1368   JNIHandles::verify();
1369   if (!silent) gclog_or_tty->print("C-heap ");
1370   os::check_heap();
1371   if (!silent) gclog_or_tty->print("code cache ");
1372   CodeCache::verify_oops();
1373   if (!silent) gclog_or_tty->print_cr("]");
1374 
1375   _verify_in_progress = false;
1376 }
1377 
1378 // Oop verification (see MacroAssembler::verify_oop)
1379 
1380 static uintptr_t _verify_oop_data[2]   = {0, (uintptr_t)-1};
1381 static uintptr_t _verify_klass_data[2] = {0, (uintptr_t)-1};
1382 
1383 
1384 #ifndef PRODUCT
1385 
1386 static void calculate_verify_data(uintptr_t verify_data[2],
1387                                   HeapWord* low_boundary,
1388                                   HeapWord* high_boundary) {
1389   assert(low_boundary < high_boundary, "bad interval");
1390 
1391   // decide which low-order bits we require to be clear:
1392   size_t alignSize = MinObjAlignmentInBytes;
1393   size_t min_object_size = CollectedHeap::min_fill_size();
1394 
1395   // make an inclusive limit:
1396   uintptr_t max = (uintptr_t)high_boundary - min_object_size*wordSize;
1397   uintptr_t min = (uintptr_t)low_boundary;
1398   assert(min < max, "bad interval");
1399   uintptr_t diff = max ^ min;
1400 
1401   // throw away enough low-order bits to make the diff vanish
1402   uintptr_t mask = (uintptr_t)(-1);
1403   while ((mask & diff) != 0)
1404     mask <<= 1;
1405   uintptr_t bits = (min & mask);
1406   assert(bits == (max & mask), "correct mask");
1407   // check an intermediate value between min and max, just to make sure:
1408   assert(bits == ((min + (max-min)/2) & mask), "correct mask");
1409 
1410   // require address alignment, too:
1411   mask |= (alignSize - 1);
1412 
1413   if (!(verify_data[0] == 0 && verify_data[1] == (uintptr_t)-1)) {
1414     assert(verify_data[0] == mask && verify_data[1] == bits, "mask stability");
1415   }
1416   verify_data[0] = mask;
1417   verify_data[1] = bits;
1418 }
1419 
1420 // Oop verification (see MacroAssembler::verify_oop)
1421 
1422 uintptr_t Universe::verify_oop_mask() {
1423   MemRegion m = heap()->reserved_region();
1424   calculate_verify_data(_verify_oop_data,
1425                         m.start(),
1426                         m.end());
1427   return _verify_oop_data[0];
1428 }
1429 
1430 
1431 
1432 uintptr_t Universe::verify_oop_bits() {
1433   verify_oop_mask();
1434   return _verify_oop_data[1];
1435 }
1436 
1437 uintptr_t Universe::verify_mark_mask() {
1438   return markOopDesc::lock_mask_in_place;
1439 }
1440 
1441 uintptr_t Universe::verify_mark_bits() {
1442   intptr_t mask = verify_mark_mask();
1443   intptr_t bits = (intptr_t)markOopDesc::prototype();
1444   assert((bits & ~mask) == 0, "no stray header bits");
1445   return bits;
1446 }
1447 #endif // PRODUCT
1448 
1449 
1450 void Universe::compute_verify_oop_data() {
1451   verify_oop_mask();
1452   verify_oop_bits();
1453   verify_mark_mask();
1454   verify_mark_bits();
1455 }
1456 
1457 
1458 void CommonMethodOopCache::init(Klass* k, Method* m, TRAPS) {
1459   if (!UseSharedSpaces) {
1460     _klass = k;
1461   }
1462 #ifndef PRODUCT
1463   else {
1464     // sharing initilization should have already set up _klass
1465     assert(_klass != NULL, "just checking");
1466   }
1467 #endif
1468 
1469   _method_idnum = m->method_idnum();
1470   assert(_method_idnum >= 0, "sanity check");
1471 }
1472 
1473 
1474 ActiveMethodOopsCache::~ActiveMethodOopsCache() {
1475   if (_prev_methods != NULL) {
1476     delete _prev_methods;
1477     _prev_methods = NULL;
1478   }
1479 }
1480 
1481 
1482 void ActiveMethodOopsCache::add_previous_version(Method* method) {
1483   assert(Thread::current()->is_VM_thread(),
1484     "only VMThread can add previous versions");
1485 
1486   // Only append the previous method if it is executing on the stack.
1487   if (method->on_stack()) {
1488 
1489     if (_prev_methods == NULL) {
1490       // This is the first previous version so make some space.
1491       // Start with 2 elements under the assumption that the class
1492       // won't be redefined much.
1493       _prev_methods = new (ResourceObj::C_HEAP, mtClass) GrowableArray<Method*>(2, true);
1494     }
1495 
1496     // RC_TRACE macro has an embedded ResourceMark
1497     RC_TRACE(0x00000100,
1498       ("add: %s(%s): adding prev version ref for cached method @%d",
1499         method->name()->as_C_string(), method->signature()->as_C_string(),
1500         _prev_methods->length()));
1501 
1502     _prev_methods->append(method);
1503   }
1504 
1505 
1506   // Since the caller is the VMThread and we are at a safepoint, this is a good
1507   // time to clear out unused method references.
1508 
1509   if (_prev_methods == NULL) return;
1510 
1511   for (int i = _prev_methods->length() - 1; i >= 0; i--) {
1512     Method* method = _prev_methods->at(i);
1513     assert(method != NULL, "weak method ref was unexpectedly cleared");
1514 
1515     if (!method->on_stack()) {
1516       // This method isn't running anymore so remove it
1517       _prev_methods->remove_at(i);
1518       MetadataFactory::free_metadata(method->method_holder()->class_loader_data(), method);
1519     } else {
1520       // RC_TRACE macro has an embedded ResourceMark
1521       RC_TRACE(0x00000400,
1522         ("add: %s(%s): previous cached method @%d is alive",
1523          method->name()->as_C_string(), method->signature()->as_C_string(), i));
1524     }
1525   }
1526 } // end add_previous_version()
1527 
1528 
1529 bool ActiveMethodOopsCache::is_same_method(const Method* method) const {
1530   InstanceKlass* ik = InstanceKlass::cast(klass());
1531   const Method* check_method = ik->method_with_idnum(method_idnum());
1532   assert(check_method != NULL, "sanity check");
1533   if (check_method == method) {
1534     // done with the easy case
1535     return true;
1536   }
1537 
1538   if (_prev_methods != NULL) {
1539     // The cached method has been redefined at least once so search
1540     // the previous versions for a match.
1541     for (int i = 0; i < _prev_methods->length(); i++) {
1542       check_method = _prev_methods->at(i);
1543       if (check_method == method) {
1544         // a previous version matches
1545         return true;
1546       }
1547     }
1548   }
1549 
1550   // either no previous versions or no previous version matched
1551   return false;
1552 }
1553 
1554 
1555 Method* LatestMethodOopCache::get_Method() {
1556   if (klass() == NULL) return NULL;
1557   InstanceKlass* ik = InstanceKlass::cast(klass());
1558   Method* m = ik->method_with_idnum(method_idnum());
1559   assert(m != NULL, "sanity check");
1560   return m;
1561 }
1562 
1563 
1564 #ifdef ASSERT
1565 // Release dummy object(s) at bottom of heap
1566 bool Universe::release_fullgc_alot_dummy() {
1567   MutexLocker ml(FullGCALot_lock);
1568   if (_fullgc_alot_dummy_array != NULL) {
1569     if (_fullgc_alot_dummy_next >= _fullgc_alot_dummy_array->length()) {
1570       // No more dummies to release, release entire array instead
1571       _fullgc_alot_dummy_array = NULL;
1572       return false;
1573     }
1574     if (!UseConcMarkSweepGC) {
1575       // Release dummy at bottom of old generation
1576       _fullgc_alot_dummy_array->obj_at_put(_fullgc_alot_dummy_next++, NULL);
1577     }
1578     // Release dummy at bottom of permanent generation
1579     _fullgc_alot_dummy_array->obj_at_put(_fullgc_alot_dummy_next++, NULL);
1580   }
1581   return true;
1582 }
1583 
1584 #endif // ASSERT