1 /*
   2  * Copyright (c) 1997, 2015, 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/stringTable.hpp"
  30 #include "classfile/systemDictionary.hpp"
  31 #include "classfile/vmSymbols.hpp"
  32 #include "code/codeCache.hpp"
  33 #include "code/dependencies.hpp"
  34 #include "gc/shared/cardTableModRefBS.hpp"
  35 #include "gc/shared/collectedHeap.inline.hpp"
  36 #include "gc/shared/gcLocker.inline.hpp"
  37 #include "gc/shared/genCollectedHeap.hpp"
  38 #include "gc/shared/generation.hpp"
  39 #include "gc/shared/gcTraceTime.inline.hpp"
  40 #include "gc/shared/space.hpp"
  41 #include "interpreter/interpreter.hpp"
  42 #include "logging/log.hpp"
  43 #include "memory/filemap.hpp"
  44 #include "memory/metadataFactory.hpp"
  45 #include "memory/metaspaceShared.hpp"
  46 #include "memory/oopFactory.hpp"
  47 #include "memory/universe.hpp"
  48 #include "memory/universe.inline.hpp"
  49 #include "oops/constantPool.hpp"
  50 #include "oops/instanceClassLoaderKlass.hpp"
  51 #include "oops/instanceKlass.hpp"
  52 #include "oops/instanceMirrorKlass.hpp"
  53 #include "oops/instanceRefKlass.hpp"
  54 #include "oops/objArrayOop.inline.hpp"
  55 #include "oops/oop.inline.hpp"
  56 #include "oops/typeArrayKlass.hpp"
  57 #include "prims/jvmtiRedefineClassesTrace.hpp"
  58 #include "runtime/arguments.hpp"
  59 #include "runtime/atomic.inline.hpp"
  60 #include "runtime/commandLineFlagConstraintList.hpp"
  61 #include "runtime/deoptimization.hpp"
  62 #include "runtime/fprofiler.hpp"
  63 #include "runtime/handles.inline.hpp"
  64 #include "runtime/init.hpp"
  65 #include "runtime/java.hpp"
  66 #include "runtime/javaCalls.hpp"
  67 #include "runtime/sharedRuntime.hpp"
  68 #include "runtime/synchronizer.hpp"
  69 #include "runtime/thread.inline.hpp"
  70 #include "runtime/timer.hpp"
  71 #include "runtime/vm_operations.hpp"
  72 #include "services/memoryService.hpp"
  73 #include "utilities/copy.hpp"
  74 #include "utilities/events.hpp"
  75 #include "utilities/hashtable.inline.hpp"
  76 #include "utilities/macros.hpp"
  77 #include "utilities/ostream.hpp"
  78 #include "utilities/preserveException.hpp"
  79 #if INCLUDE_ALL_GCS
  80 #include "gc/cms/cmsCollectorPolicy.hpp"
  81 #include "gc/g1/g1CollectedHeap.inline.hpp"
  82 #include "gc/g1/g1CollectorPolicy.hpp"
  83 #include "gc/parallel/parallelScavengeHeap.hpp"
  84 #include "gc/shared/adaptiveSizePolicy.hpp"
  85 #endif // INCLUDE_ALL_GCS
  86 #if INCLUDE_CDS
  87 #include "classfile/sharedClassUtil.hpp"
  88 #endif
  89 
  90 // Known objects
  91 Klass* Universe::_boolArrayKlassObj                 = NULL;
  92 Klass* Universe::_byteArrayKlassObj                 = NULL;
  93 Klass* Universe::_charArrayKlassObj                 = NULL;
  94 Klass* Universe::_intArrayKlassObj                  = NULL;
  95 Klass* Universe::_shortArrayKlassObj                = NULL;
  96 Klass* Universe::_longArrayKlassObj                 = NULL;
  97 Klass* Universe::_singleArrayKlassObj               = NULL;
  98 Klass* Universe::_doubleArrayKlassObj               = NULL;
  99 Klass* Universe::_typeArrayKlassObjs[T_VOID+1]      = { NULL /*, NULL...*/ };
 100 Klass* Universe::_objectArrayKlassObj               = NULL;
 101 oop Universe::_int_mirror                             = NULL;
 102 oop Universe::_float_mirror                           = NULL;
 103 oop Universe::_double_mirror                          = NULL;
 104 oop Universe::_byte_mirror                            = NULL;
 105 oop Universe::_bool_mirror                            = NULL;
 106 oop Universe::_char_mirror                            = NULL;
 107 oop Universe::_long_mirror                            = NULL;
 108 oop Universe::_short_mirror                           = NULL;
 109 oop Universe::_void_mirror                            = NULL;
 110 oop Universe::_mirrors[T_VOID+1]                      = { NULL /*, NULL...*/ };
 111 oop Universe::_main_thread_group                      = NULL;
 112 oop Universe::_system_thread_group                    = NULL;
 113 objArrayOop Universe::_the_empty_class_klass_array    = NULL;
 114 Array<Klass*>* Universe::_the_array_interfaces_array = NULL;
 115 oop Universe::_the_null_string                        = NULL;
 116 oop Universe::_the_min_jint_string                   = NULL;
 117 LatestMethodCache* Universe::_finalizer_register_cache = NULL;
 118 LatestMethodCache* Universe::_loader_addClass_cache    = NULL;
 119 LatestMethodCache* Universe::_pd_implies_cache         = NULL;
 120 LatestMethodCache* Universe::_throw_illegal_access_error_cache = NULL;
 121 LatestMethodCache* Universe::_do_stack_walk_cache     = NULL;
 122 oop Universe::_out_of_memory_error_java_heap          = NULL;
 123 oop Universe::_out_of_memory_error_metaspace          = NULL;
 124 oop Universe::_out_of_memory_error_class_metaspace    = NULL;
 125 oop Universe::_out_of_memory_error_array_size         = NULL;
 126 oop Universe::_out_of_memory_error_gc_overhead_limit  = NULL;
 127 oop Universe::_out_of_memory_error_realloc_objects    = NULL;
 128 oop Universe::_delayed_stack_overflow_error_message   = NULL;
 129 objArrayOop Universe::_preallocated_out_of_memory_error_array = NULL;
 130 volatile jint Universe::_preallocated_out_of_memory_error_avail_count = 0;
 131 bool Universe::_verify_in_progress                    = false;
 132 oop Universe::_null_ptr_exception_instance            = NULL;
 133 oop Universe::_arithmetic_exception_instance          = NULL;
 134 oop Universe::_virtual_machine_error_instance         = NULL;
 135 oop Universe::_vm_exception                           = NULL;
 136 oop Universe::_allocation_context_notification_obj    = NULL;
 137 
 138 Array<int>* Universe::_the_empty_int_array            = NULL;
 139 Array<u2>* Universe::_the_empty_short_array           = NULL;
 140 Array<Klass*>* Universe::_the_empty_klass_array     = NULL;
 141 Array<Method*>* Universe::_the_empty_method_array   = NULL;
 142 
 143 // These variables are guarded by FullGCALot_lock.
 144 debug_only(objArrayOop Universe::_fullgc_alot_dummy_array = NULL;)
 145 debug_only(int Universe::_fullgc_alot_dummy_next      = 0;)
 146 
 147 // Heap
 148 int             Universe::_verify_count = 0;
 149 
 150 // Oop verification (see MacroAssembler::verify_oop)
 151 uintptr_t       Universe::_verify_oop_mask = 0;
 152 uintptr_t       Universe::_verify_oop_bits = (uintptr_t) -1;
 153 
 154 int             Universe::_base_vtable_size = 0;
 155 bool            Universe::_bootstrapping = false;
 156 bool            Universe::_fully_initialized = false;
 157 
 158 size_t          Universe::_heap_capacity_at_last_gc;
 159 size_t          Universe::_heap_used_at_last_gc = 0;
 160 
 161 CollectedHeap*  Universe::_collectedHeap = NULL;
 162 
 163 NarrowPtrStruct Universe::_narrow_oop = { NULL, 0, true };
 164 NarrowPtrStruct Universe::_narrow_klass = { NULL, 0, true };
 165 address Universe::_narrow_ptrs_base;
 166 
 167 void Universe::basic_type_classes_do(void f(Klass*)) {
 168   f(boolArrayKlassObj());
 169   f(byteArrayKlassObj());
 170   f(charArrayKlassObj());
 171   f(intArrayKlassObj());
 172   f(shortArrayKlassObj());
 173   f(longArrayKlassObj());
 174   f(singleArrayKlassObj());
 175   f(doubleArrayKlassObj());
 176 }
 177 
 178 void Universe::oops_do(OopClosure* f, bool do_all) {
 179 
 180   f->do_oop((oop*) &_int_mirror);
 181   f->do_oop((oop*) &_float_mirror);
 182   f->do_oop((oop*) &_double_mirror);
 183   f->do_oop((oop*) &_byte_mirror);
 184   f->do_oop((oop*) &_bool_mirror);
 185   f->do_oop((oop*) &_char_mirror);
 186   f->do_oop((oop*) &_long_mirror);
 187   f->do_oop((oop*) &_short_mirror);
 188   f->do_oop((oop*) &_void_mirror);
 189 
 190   for (int i = T_BOOLEAN; i < T_VOID+1; i++) {
 191     f->do_oop((oop*) &_mirrors[i]);
 192   }
 193   assert(_mirrors[0] == NULL && _mirrors[T_BOOLEAN - 1] == NULL, "checking");
 194 
 195   f->do_oop((oop*)&_the_empty_class_klass_array);
 196   f->do_oop((oop*)&_the_null_string);
 197   f->do_oop((oop*)&_the_min_jint_string);
 198   f->do_oop((oop*)&_out_of_memory_error_java_heap);
 199   f->do_oop((oop*)&_out_of_memory_error_metaspace);
 200   f->do_oop((oop*)&_out_of_memory_error_class_metaspace);
 201   f->do_oop((oop*)&_out_of_memory_error_array_size);
 202   f->do_oop((oop*)&_out_of_memory_error_gc_overhead_limit);
 203   f->do_oop((oop*)&_out_of_memory_error_realloc_objects);
 204   f->do_oop((oop*)&_delayed_stack_overflow_error_message);
 205   f->do_oop((oop*)&_preallocated_out_of_memory_error_array);
 206   f->do_oop((oop*)&_null_ptr_exception_instance);
 207   f->do_oop((oop*)&_arithmetic_exception_instance);
 208   f->do_oop((oop*)&_virtual_machine_error_instance);
 209   f->do_oop((oop*)&_main_thread_group);
 210   f->do_oop((oop*)&_system_thread_group);
 211   f->do_oop((oop*)&_vm_exception);
 212   f->do_oop((oop*)&_allocation_context_notification_obj);
 213   debug_only(f->do_oop((oop*)&_fullgc_alot_dummy_array);)
 214 }
 215 
 216 // Serialize metadata in and out of CDS archive, not oops.
 217 void Universe::serialize(SerializeClosure* f, bool do_all) {
 218 
 219   f->do_ptr((void**)&_boolArrayKlassObj);
 220   f->do_ptr((void**)&_byteArrayKlassObj);
 221   f->do_ptr((void**)&_charArrayKlassObj);
 222   f->do_ptr((void**)&_intArrayKlassObj);
 223   f->do_ptr((void**)&_shortArrayKlassObj);
 224   f->do_ptr((void**)&_longArrayKlassObj);
 225   f->do_ptr((void**)&_singleArrayKlassObj);
 226   f->do_ptr((void**)&_doubleArrayKlassObj);
 227   f->do_ptr((void**)&_objectArrayKlassObj);
 228 
 229   {
 230     for (int i = 0; i < T_VOID+1; i++) {
 231       if (_typeArrayKlassObjs[i] != NULL) {
 232         assert(i >= T_BOOLEAN, "checking");
 233         f->do_ptr((void**)&_typeArrayKlassObjs[i]);
 234       } else if (do_all) {
 235         f->do_ptr((void**)&_typeArrayKlassObjs[i]);
 236       }
 237     }
 238   }
 239 
 240   f->do_ptr((void**)&_the_array_interfaces_array);
 241   f->do_ptr((void**)&_the_empty_int_array);
 242   f->do_ptr((void**)&_the_empty_short_array);
 243   f->do_ptr((void**)&_the_empty_method_array);
 244   f->do_ptr((void**)&_the_empty_klass_array);
 245   _finalizer_register_cache->serialize(f);
 246   _loader_addClass_cache->serialize(f);
 247   _pd_implies_cache->serialize(f);
 248   _throw_illegal_access_error_cache->serialize(f);
 249   _do_stack_walk_cache->serialize(f);
 250 }
 251 
 252 void Universe::check_alignment(uintx size, uintx alignment, const char* name) {
 253   if (size < alignment || size % alignment != 0) {
 254     vm_exit_during_initialization(
 255       err_msg("Size of %s (" UINTX_FORMAT " bytes) must be aligned to " UINTX_FORMAT " bytes", name, size, alignment));
 256   }
 257 }
 258 
 259 void initialize_basic_type_klass(Klass* k, TRAPS) {
 260   Klass* ok = SystemDictionary::Object_klass();
 261   if (UseSharedSpaces) {
 262     ClassLoaderData* loader_data = ClassLoaderData::the_null_class_loader_data();
 263     assert(k->super() == ok, "u3");
 264     k->restore_unshareable_info(loader_data, Handle(), CHECK);
 265   } else {
 266     k->initialize_supers(ok, CHECK);
 267   }
 268   k->append_to_sibling_list();
 269 }
 270 
 271 void Universe::genesis(TRAPS) {
 272   ResourceMark rm;
 273 
 274   { FlagSetting fs(_bootstrapping, true);
 275 
 276     { MutexLocker mc(Compile_lock);
 277 
 278       // determine base vtable size; without that we cannot create the array klasses
 279       compute_base_vtable_size();
 280 
 281       if (!UseSharedSpaces) {
 282         _boolArrayKlassObj      = TypeArrayKlass::create_klass(T_BOOLEAN, sizeof(jboolean), CHECK);
 283         _charArrayKlassObj      = TypeArrayKlass::create_klass(T_CHAR,    sizeof(jchar),    CHECK);
 284         _singleArrayKlassObj    = TypeArrayKlass::create_klass(T_FLOAT,   sizeof(jfloat),   CHECK);
 285         _doubleArrayKlassObj    = TypeArrayKlass::create_klass(T_DOUBLE,  sizeof(jdouble),  CHECK);
 286         _byteArrayKlassObj      = TypeArrayKlass::create_klass(T_BYTE,    sizeof(jbyte),    CHECK);
 287         _shortArrayKlassObj     = TypeArrayKlass::create_klass(T_SHORT,   sizeof(jshort),   CHECK);
 288         _intArrayKlassObj       = TypeArrayKlass::create_klass(T_INT,     sizeof(jint),     CHECK);
 289         _longArrayKlassObj      = TypeArrayKlass::create_klass(T_LONG,    sizeof(jlong),    CHECK);
 290 
 291         _typeArrayKlassObjs[T_BOOLEAN] = _boolArrayKlassObj;
 292         _typeArrayKlassObjs[T_CHAR]    = _charArrayKlassObj;
 293         _typeArrayKlassObjs[T_FLOAT]   = _singleArrayKlassObj;
 294         _typeArrayKlassObjs[T_DOUBLE]  = _doubleArrayKlassObj;
 295         _typeArrayKlassObjs[T_BYTE]    = _byteArrayKlassObj;
 296         _typeArrayKlassObjs[T_SHORT]   = _shortArrayKlassObj;
 297         _typeArrayKlassObjs[T_INT]     = _intArrayKlassObj;
 298         _typeArrayKlassObjs[T_LONG]    = _longArrayKlassObj;
 299 
 300         ClassLoaderData* null_cld = ClassLoaderData::the_null_class_loader_data();
 301 
 302         _the_array_interfaces_array = MetadataFactory::new_array<Klass*>(null_cld, 2, NULL, CHECK);
 303         _the_empty_int_array        = MetadataFactory::new_array<int>(null_cld, 0, CHECK);
 304         _the_empty_short_array      = MetadataFactory::new_array<u2>(null_cld, 0, CHECK);
 305         _the_empty_method_array     = MetadataFactory::new_array<Method*>(null_cld, 0, CHECK);
 306         _the_empty_klass_array      = MetadataFactory::new_array<Klass*>(null_cld, 0, CHECK);
 307       }
 308     }
 309 
 310     vmSymbols::initialize(CHECK);
 311 
 312     SystemDictionary::initialize(CHECK);
 313 
 314     Klass* ok = SystemDictionary::Object_klass();
 315 
 316     _the_null_string            = StringTable::intern("null", CHECK);
 317     _the_min_jint_string       = StringTable::intern("-2147483648", CHECK);
 318 
 319     if (UseSharedSpaces) {
 320       // Verify shared interfaces array.
 321       assert(_the_array_interfaces_array->at(0) ==
 322              SystemDictionary::Cloneable_klass(), "u3");
 323       assert(_the_array_interfaces_array->at(1) ==
 324              SystemDictionary::Serializable_klass(), "u3");
 325       MetaspaceShared::fixup_shared_string_regions();
 326     } else {
 327       // Set up shared interfaces array.  (Do this before supers are set up.)
 328       _the_array_interfaces_array->at_put(0, SystemDictionary::Cloneable_klass());
 329       _the_array_interfaces_array->at_put(1, SystemDictionary::Serializable_klass());
 330     }
 331 
 332     initialize_basic_type_klass(boolArrayKlassObj(), CHECK);
 333     initialize_basic_type_klass(charArrayKlassObj(), CHECK);
 334     initialize_basic_type_klass(singleArrayKlassObj(), CHECK);
 335     initialize_basic_type_klass(doubleArrayKlassObj(), CHECK);
 336     initialize_basic_type_klass(byteArrayKlassObj(), CHECK);
 337     initialize_basic_type_klass(shortArrayKlassObj(), CHECK);
 338     initialize_basic_type_klass(intArrayKlassObj(), CHECK);
 339     initialize_basic_type_klass(longArrayKlassObj(), CHECK);
 340   } // end of core bootstrapping
 341 
 342   // Maybe this could be lifted up now that object array can be initialized
 343   // during the bootstrapping.
 344 
 345   // OLD
 346   // Initialize _objectArrayKlass after core bootstraping to make
 347   // sure the super class is set up properly for _objectArrayKlass.
 348   // ---
 349   // NEW
 350   // Since some of the old system object arrays have been converted to
 351   // ordinary object arrays, _objectArrayKlass will be loaded when
 352   // SystemDictionary::initialize(CHECK); is run. See the extra check
 353   // for Object_klass_loaded in objArrayKlassKlass::allocate_objArray_klass_impl.
 354   _objectArrayKlassObj = InstanceKlass::
 355     cast(SystemDictionary::Object_klass())->array_klass(1, CHECK);
 356   // OLD
 357   // Add the class to the class hierarchy manually to make sure that
 358   // its vtable is initialized after core bootstrapping is completed.
 359   // ---
 360   // New
 361   // Have already been initialized.
 362   _objectArrayKlassObj->append_to_sibling_list();
 363 
 364   #ifdef ASSERT
 365   if (FullGCALot) {
 366     // Allocate an array of dummy objects.
 367     // We'd like these to be at the bottom of the old generation,
 368     // so that when we free one and then collect,
 369     // (almost) the whole heap moves
 370     // and we find out if we actually update all the oops correctly.
 371     // But we can't allocate directly in the old generation,
 372     // so we allocate wherever, and hope that the first collection
 373     // moves these objects to the bottom of the old generation.
 374     // We can allocate directly in the permanent generation, so we do.
 375     int size;
 376     if (UseConcMarkSweepGC) {
 377       warning("Using +FullGCALot with concurrent mark sweep gc "
 378               "will not force all objects to relocate");
 379       size = FullGCALotDummies;
 380     } else {
 381       size = FullGCALotDummies * 2;
 382     }
 383     objArrayOop    naked_array = oopFactory::new_objArray(SystemDictionary::Object_klass(), size, CHECK);
 384     objArrayHandle dummy_array(THREAD, naked_array);
 385     int i = 0;
 386     while (i < size) {
 387         // Allocate dummy in old generation
 388       oop dummy = SystemDictionary::Object_klass()->allocate_instance(CHECK);
 389       dummy_array->obj_at_put(i++, dummy);
 390     }
 391     {
 392       // Only modify the global variable inside the mutex.
 393       // If we had a race to here, the other dummy_array instances
 394       // and their elements just get dropped on the floor, which is fine.
 395       MutexLocker ml(FullGCALot_lock);
 396       if (_fullgc_alot_dummy_array == NULL) {
 397         _fullgc_alot_dummy_array = dummy_array();
 398       }
 399     }
 400     assert(i == _fullgc_alot_dummy_array->length(), "just checking");
 401   }
 402   #endif
 403 
 404   // Initialize dependency array for null class loader
 405   ClassLoaderData::the_null_class_loader_data()->init_dependencies(CHECK);
 406 
 407 }
 408 
 409 // CDS support for patching vtables in metadata in the shared archive.
 410 // All types inherited from Metadata have vtables, but not types inherited
 411 // from MetaspaceObj, because the latter does not have virtual functions.
 412 // If the metadata type has a vtable, it cannot be shared in the read-only
 413 // section of the CDS archive, because the vtable pointer is patched.
 414 static inline void add_vtable(void** list, int* n, void* o, int count) {
 415   guarantee((*n) < count, "vtable list too small");
 416   void* vtable = dereference_vptr(o);
 417   assert(*(void**)(vtable) != NULL, "invalid vtable");
 418   list[(*n)++] = vtable;
 419 }
 420 
 421 void Universe::init_self_patching_vtbl_list(void** list, int count) {
 422   int n = 0;
 423   { InstanceKlass o;          add_vtable(list, &n, &o, count); }
 424   { InstanceClassLoaderKlass o; add_vtable(list, &n, &o, count); }
 425   { InstanceMirrorKlass o;    add_vtable(list, &n, &o, count); }
 426   { InstanceRefKlass o;       add_vtable(list, &n, &o, count); }
 427   { TypeArrayKlass o;         add_vtable(list, &n, &o, count); }
 428   { ObjArrayKlass o;          add_vtable(list, &n, &o, count); }
 429   { Method o;                 add_vtable(list, &n, &o, count); }
 430   { ConstantPool o;           add_vtable(list, &n, &o, count); }
 431 }
 432 
 433 void Universe::initialize_basic_type_mirrors(TRAPS) {
 434     assert(_int_mirror==NULL, "basic type mirrors already initialized");
 435     _int_mirror     =
 436       java_lang_Class::create_basic_type_mirror("int",    T_INT, CHECK);
 437     _float_mirror   =
 438       java_lang_Class::create_basic_type_mirror("float",  T_FLOAT,   CHECK);
 439     _double_mirror  =
 440       java_lang_Class::create_basic_type_mirror("double", T_DOUBLE,  CHECK);
 441     _byte_mirror    =
 442       java_lang_Class::create_basic_type_mirror("byte",   T_BYTE, CHECK);
 443     _bool_mirror    =
 444       java_lang_Class::create_basic_type_mirror("boolean",T_BOOLEAN, CHECK);
 445     _char_mirror    =
 446       java_lang_Class::create_basic_type_mirror("char",   T_CHAR, CHECK);
 447     _long_mirror    =
 448       java_lang_Class::create_basic_type_mirror("long",   T_LONG, CHECK);
 449     _short_mirror   =
 450       java_lang_Class::create_basic_type_mirror("short",  T_SHORT,   CHECK);
 451     _void_mirror    =
 452       java_lang_Class::create_basic_type_mirror("void",   T_VOID, CHECK);
 453 
 454     _mirrors[T_INT]     = _int_mirror;
 455     _mirrors[T_FLOAT]   = _float_mirror;
 456     _mirrors[T_DOUBLE]  = _double_mirror;
 457     _mirrors[T_BYTE]    = _byte_mirror;
 458     _mirrors[T_BOOLEAN] = _bool_mirror;
 459     _mirrors[T_CHAR]    = _char_mirror;
 460     _mirrors[T_LONG]    = _long_mirror;
 461     _mirrors[T_SHORT]   = _short_mirror;
 462     _mirrors[T_VOID]    = _void_mirror;
 463   //_mirrors[T_OBJECT]  = _object_klass->java_mirror();
 464   //_mirrors[T_ARRAY]   = _object_klass->java_mirror();
 465 }
 466 
 467 void Universe::fixup_mirrors(TRAPS) {
 468   // Bootstrap problem: all classes gets a mirror (java.lang.Class instance) assigned eagerly,
 469   // but we cannot do that for classes created before java.lang.Class is loaded. Here we simply
 470   // walk over permanent objects created so far (mostly classes) and fixup their mirrors. Note
 471   // that the number of objects allocated at this point is very small.
 472   assert(SystemDictionary::Class_klass_loaded(), "java.lang.Class should be loaded");
 473   HandleMark hm(THREAD);
 474   // Cache the start of the static fields
 475   InstanceMirrorKlass::init_offset_of_static_fields();
 476 
 477   GrowableArray <Klass*>* list = java_lang_Class::fixup_mirror_list();
 478   int list_length = list->length();
 479   for (int i = 0; i < list_length; i++) {
 480     Klass* k = list->at(i);
 481     assert(k->is_klass(), "List should only hold classes");
 482     EXCEPTION_MARK;
 483     KlassHandle kh(THREAD, k);
 484     java_lang_Class::fixup_mirror(kh, CATCH);
 485 }
 486   delete java_lang_Class::fixup_mirror_list();
 487   java_lang_Class::set_fixup_mirror_list(NULL);
 488 }
 489 
 490 static bool has_run_finalizers_on_exit = false;
 491 
 492 void Universe::run_finalizers_on_exit() {
 493   if (has_run_finalizers_on_exit) return;
 494   has_run_finalizers_on_exit = true;
 495 
 496   // Called on VM exit. This ought to be run in a separate thread.
 497   log_trace(ref)("Callback to run finalizers on exit");
 498   {
 499     PRESERVE_EXCEPTION_MARK;
 500     KlassHandle finalizer_klass(THREAD, SystemDictionary::Finalizer_klass());
 501     JavaValue result(T_VOID);
 502     JavaCalls::call_static(
 503       &result,
 504       finalizer_klass,
 505       vmSymbols::run_finalizers_on_exit_name(),
 506       vmSymbols::void_method_signature(),
 507       THREAD
 508     );
 509     // Ignore any pending exceptions
 510     CLEAR_PENDING_EXCEPTION;
 511   }
 512 }
 513 
 514 
 515 // initialize_vtable could cause gc if
 516 // 1) we specified true to initialize_vtable and
 517 // 2) this ran after gc was enabled
 518 // In case those ever change we use handles for oops
 519 void Universe::reinitialize_vtable_of(KlassHandle k_h, TRAPS) {
 520   // init vtable of k and all subclasses
 521   Klass* ko = k_h();
 522   klassVtable* vt = ko->vtable();
 523   if (vt) vt->initialize_vtable(false, CHECK);
 524   if (ko->is_instance_klass()) {
 525     for (KlassHandle s_h(THREAD, ko->subklass());
 526          s_h() != NULL;
 527          s_h = KlassHandle(THREAD, s_h()->next_sibling())) {
 528       reinitialize_vtable_of(s_h, CHECK);
 529     }
 530   }
 531 }
 532 
 533 
 534 void initialize_itable_for_klass(Klass* k, TRAPS) {
 535   InstanceKlass::cast(k)->itable()->initialize_itable(false, CHECK);
 536 }
 537 
 538 
 539 void Universe::reinitialize_itables(TRAPS) {
 540   SystemDictionary::classes_do(initialize_itable_for_klass, CHECK);
 541 
 542 }
 543 
 544 
 545 bool Universe::on_page_boundary(void* addr) {
 546   return ((uintptr_t) addr) % os::vm_page_size() == 0;
 547 }
 548 
 549 
 550 bool Universe::should_fill_in_stack_trace(Handle throwable) {
 551   // never attempt to fill in the stack trace of preallocated errors that do not have
 552   // backtrace. These errors are kept alive forever and may be "re-used" when all
 553   // preallocated errors with backtrace have been consumed. Also need to avoid
 554   // a potential loop which could happen if an out of memory occurs when attempting
 555   // to allocate the backtrace.
 556   return ((throwable() != Universe::_out_of_memory_error_java_heap) &&
 557           (throwable() != Universe::_out_of_memory_error_metaspace)  &&
 558           (throwable() != Universe::_out_of_memory_error_class_metaspace)  &&
 559           (throwable() != Universe::_out_of_memory_error_array_size) &&
 560           (throwable() != Universe::_out_of_memory_error_gc_overhead_limit) &&
 561           (throwable() != Universe::_out_of_memory_error_realloc_objects));
 562 }
 563 
 564 
 565 oop Universe::gen_out_of_memory_error(oop default_err) {
 566   // generate an out of memory error:
 567   // - if there is a preallocated error with backtrace available then return it wth
 568   //   a filled in stack trace.
 569   // - if there are no preallocated errors with backtrace available then return
 570   //   an error without backtrace.
 571   int next;
 572   if (_preallocated_out_of_memory_error_avail_count > 0) {
 573     next = (int)Atomic::add(-1, &_preallocated_out_of_memory_error_avail_count);
 574     assert(next < (int)PreallocatedOutOfMemoryErrorCount, "avail count is corrupt");
 575   } else {
 576     next = -1;
 577   }
 578   if (next < 0) {
 579     // all preallocated errors have been used.
 580     // return default
 581     return default_err;
 582   } else {
 583     // get the error object at the slot and set set it to NULL so that the
 584     // array isn't keeping it alive anymore.
 585     oop exc = preallocated_out_of_memory_errors()->obj_at(next);
 586     assert(exc != NULL, "slot has been used already");
 587     preallocated_out_of_memory_errors()->obj_at_put(next, NULL);
 588 
 589     // use the message from the default error
 590     oop msg = java_lang_Throwable::message(default_err);
 591     assert(msg != NULL, "no message");
 592     java_lang_Throwable::set_message(exc, msg);
 593 
 594     // populate the stack trace and return it.
 595     java_lang_Throwable::fill_in_stack_trace_of_preallocated_backtrace(exc);
 596     return exc;
 597   }
 598 }
 599 
 600 intptr_t Universe::_non_oop_bits = 0;
 601 
 602 void* Universe::non_oop_word() {
 603   // Neither the high bits nor the low bits of this value is allowed
 604   // to look like (respectively) the high or low bits of a real oop.
 605   //
 606   // High and low are CPU-specific notions, but low always includes
 607   // the low-order bit.  Since oops are always aligned at least mod 4,
 608   // setting the low-order bit will ensure that the low half of the
 609   // word will never look like that of a real oop.
 610   //
 611   // Using the OS-supplied non-memory-address word (usually 0 or -1)
 612   // will take care of the high bits, however many there are.
 613 
 614   if (_non_oop_bits == 0) {
 615     _non_oop_bits = (intptr_t)os::non_memory_address_word() | 1;
 616   }
 617 
 618   return (void*)_non_oop_bits;
 619 }
 620 
 621 jint universe_init() {
 622   assert(!Universe::_fully_initialized, "called after initialize_vtables");
 623   guarantee(1 << LogHeapWordSize == sizeof(HeapWord),
 624          "LogHeapWordSize is incorrect.");
 625   guarantee(sizeof(oop) >= sizeof(HeapWord), "HeapWord larger than oop?");
 626   guarantee(sizeof(oop) % sizeof(HeapWord) == 0,
 627             "oop size is not not a multiple of HeapWord size");
 628   TraceTime timer("Genesis", TraceStartupTime);
 629   JavaClasses::compute_hard_coded_offsets();
 630 
 631   jint status = Universe::initialize_heap();
 632   if (status != JNI_OK) {
 633     return status;
 634   }
 635 
 636   Metaspace::global_initialize();
 637 
 638   // Checks 'AfterMemoryInit' constraints.
 639   if (!CommandLineFlagConstraintList::check_constraints(CommandLineFlagConstraint::AfterMemoryInit)) {
 640     return JNI_EINVAL;
 641   }
 642 
 643   // Create memory for metadata.  Must be after initializing heap for
 644   // DumpSharedSpaces.
 645   ClassLoaderData::init_null_class_loader_data();
 646 
 647   // We have a heap so create the Method* caches before
 648   // Metaspace::initialize_shared_spaces() tries to populate them.
 649   Universe::_finalizer_register_cache = new LatestMethodCache();
 650   Universe::_loader_addClass_cache    = new LatestMethodCache();
 651   Universe::_pd_implies_cache         = new LatestMethodCache();
 652   Universe::_throw_illegal_access_error_cache = new LatestMethodCache();
 653   Universe::_do_stack_walk_cache = new LatestMethodCache();
 654 
 655   if (UseSharedSpaces) {
 656     // Read the data structures supporting the shared spaces (shared
 657     // system dictionary, symbol table, etc.).  After that, access to
 658     // the file (other than the mapped regions) is no longer needed, and
 659     // the file is closed. Closing the file does not affect the
 660     // currently mapped regions.
 661     MetaspaceShared::initialize_shared_spaces();
 662     StringTable::create_table();
 663   } else {
 664     SymbolTable::create_table();
 665     StringTable::create_table();
 666     ClassLoader::create_package_info_table();
 667 
 668     if (DumpSharedSpaces) {
 669       MetaspaceShared::prepare_for_dumping();
 670     }
 671   }
 672 
 673   return JNI_OK;
 674 }
 675 
 676 CollectedHeap* Universe::create_heap() {
 677   assert(_collectedHeap == NULL, "Heap already created");
 678 #if !INCLUDE_ALL_GCS
 679   if (UseParallelGC) {
 680     fatal("UseParallelGC not supported in this VM.");
 681   } else if (UseG1GC) {
 682     fatal("UseG1GC not supported in this VM.");
 683   } else if (UseConcMarkSweepGC) {
 684     fatal("UseConcMarkSweepGC not supported in this VM.");
 685 #else
 686   if (UseParallelGC) {
 687     return Universe::create_heap_with_policy<ParallelScavengeHeap, GenerationSizer>();
 688   } else if (UseG1GC) {
 689     return Universe::create_heap_with_policy<G1CollectedHeap, G1CollectorPolicy>();
 690   } else if (UseConcMarkSweepGC) {
 691     return Universe::create_heap_with_policy<GenCollectedHeap, ConcurrentMarkSweepPolicy>();
 692 #endif
 693   } else if (UseSerialGC) {
 694     return Universe::create_heap_with_policy<GenCollectedHeap, MarkSweepPolicy>();
 695   }
 696 
 697   ShouldNotReachHere();
 698   return NULL;
 699 }
 700 
 701 // Choose the heap base address and oop encoding mode
 702 // when compressed oops are used:
 703 // Unscaled  - Use 32-bits oops without encoding when
 704 //     NarrowOopHeapBaseMin + heap_size < 4Gb
 705 // ZeroBased - Use zero based compressed oops with encoding when
 706 //     NarrowOopHeapBaseMin + heap_size < 32Gb
 707 // HeapBased - Use compressed oops with heap base + encoding.
 708 
 709 jint Universe::initialize_heap() {
 710   jint status = JNI_ERR;
 711 
 712   _collectedHeap = create_heap_ext();
 713   if (_collectedHeap == NULL) {
 714     _collectedHeap = create_heap();
 715   }
 716 
 717   status = _collectedHeap->initialize();
 718   if (status != JNI_OK) {
 719     return status;
 720   }
 721   log_info(gc)("Using %s", _collectedHeap->name());
 722 
 723   ThreadLocalAllocBuffer::set_max_size(Universe::heap()->max_tlab_size());
 724 
 725 #ifdef _LP64
 726   if (UseCompressedOops) {
 727     // Subtract a page because something can get allocated at heap base.
 728     // This also makes implicit null checking work, because the
 729     // memory+1 page below heap_base needs to cause a signal.
 730     // See needs_explicit_null_check.
 731     // Only set the heap base for compressed oops because it indicates
 732     // compressed oops for pstack code.
 733     if ((uint64_t)Universe::heap()->reserved_region().end() > UnscaledOopHeapMax) {
 734       // Didn't reserve heap below 4Gb.  Must shift.
 735       Universe::set_narrow_oop_shift(LogMinObjAlignmentInBytes);
 736     }
 737     if ((uint64_t)Universe::heap()->reserved_region().end() <= OopEncodingHeapMax) {
 738       // Did reserve heap below 32Gb. Can use base == 0;
 739       Universe::set_narrow_oop_base(0);
 740     }
 741 
 742     Universe::set_narrow_ptrs_base(Universe::narrow_oop_base());
 743 
 744     if (PrintCompressedOopsMode || (PrintMiscellaneous && Verbose)) {
 745       Universe::print_compressed_oops_mode(tty);
 746     }
 747 
 748     // Tell tests in which mode we run.
 749     Arguments::PropertyList_add(new SystemProperty("java.vm.compressedOopsMode",
 750                                                    narrow_oop_mode_to_string(narrow_oop_mode()),
 751                                                    false));
 752   }
 753   // Universe::narrow_oop_base() is one page below the heap.
 754   assert((intptr_t)Universe::narrow_oop_base() <= (intptr_t)(Universe::heap()->base() -
 755          os::vm_page_size()) ||
 756          Universe::narrow_oop_base() == NULL, "invalid value");
 757   assert(Universe::narrow_oop_shift() == LogMinObjAlignmentInBytes ||
 758          Universe::narrow_oop_shift() == 0, "invalid value");
 759 #endif
 760 
 761   // We will never reach the CATCH below since Exceptions::_throw will cause
 762   // the VM to exit if an exception is thrown during initialization
 763 
 764   if (UseTLAB) {
 765     assert(Universe::heap()->supports_tlab_allocation(),
 766            "Should support thread-local allocation buffers");
 767     ThreadLocalAllocBuffer::startup_initialization();
 768   }
 769   return JNI_OK;
 770 }
 771 
 772 void Universe::print_compressed_oops_mode(outputStream* st) {
 773   st->print("heap address: " PTR_FORMAT ", size: " SIZE_FORMAT " MB",
 774               p2i(Universe::heap()->base()), Universe::heap()->reserved_region().byte_size()/M);
 775 
 776   st->print(", Compressed Oops mode: %s", narrow_oop_mode_to_string(narrow_oop_mode()));
 777 
 778   if (Universe::narrow_oop_base() != 0) {
 779     st->print(": " PTR_FORMAT, p2i(Universe::narrow_oop_base()));
 780   }
 781 
 782   if (Universe::narrow_oop_shift() != 0) {
 783     st->print(", Oop shift amount: %d", Universe::narrow_oop_shift());
 784   }
 785 
 786   if (!Universe::narrow_oop_use_implicit_null_checks()) {
 787     st->print(", no protected page in front of the heap");
 788   }
 789   st->cr();
 790 }
 791 
 792 ReservedSpace Universe::reserve_heap(size_t heap_size, size_t alignment) {
 793 
 794   assert(alignment <= Arguments::conservative_max_heap_alignment(),
 795          "actual alignment " SIZE_FORMAT " must be within maximum heap alignment " SIZE_FORMAT,
 796          alignment, Arguments::conservative_max_heap_alignment());
 797 
 798   size_t total_reserved = align_size_up(heap_size, alignment);
 799   assert(!UseCompressedOops || (total_reserved <= (OopEncodingHeapMax - os::vm_page_size())),
 800       "heap size is too big for compressed oops");
 801 
 802   bool use_large_pages = UseLargePages && is_size_aligned(alignment, os::large_page_size());
 803   assert(!UseLargePages
 804       || UseParallelGC
 805       || use_large_pages, "Wrong alignment to use large pages");
 806 
 807   // Now create the space.
 808   ReservedHeapSpace total_rs(total_reserved, alignment, use_large_pages);
 809 
 810   if (total_rs.is_reserved()) {
 811     assert((total_reserved == total_rs.size()) && ((uintptr_t)total_rs.base() % alignment == 0),
 812            "must be exactly of required size and alignment");
 813     // We are good.
 814 
 815     if (UseCompressedOops) {
 816       // Universe::initialize_heap() will reset this to NULL if unscaled
 817       // or zero-based narrow oops are actually used.
 818       // Else heap start and base MUST differ, so that NULL can be encoded nonambigous.
 819       Universe::set_narrow_oop_base((address)total_rs.compressed_oop_base());
 820     }
 821 
 822     return total_rs;
 823   }
 824 
 825   vm_exit_during_initialization(
 826     err_msg("Could not reserve enough space for " SIZE_FORMAT "KB object heap",
 827             total_reserved/K));
 828 
 829   // satisfy compiler
 830   ShouldNotReachHere();
 831   return ReservedHeapSpace(0, 0, false);
 832 }
 833 
 834 
 835 // It's the caller's responsibility to ensure glitch-freedom
 836 // (if required).
 837 void Universe::update_heap_info_at_gc() {
 838   _heap_capacity_at_last_gc = heap()->capacity();
 839   _heap_used_at_last_gc     = heap()->used();
 840 }
 841 
 842 
 843 const char* Universe::narrow_oop_mode_to_string(Universe::NARROW_OOP_MODE mode) {
 844   switch (mode) {
 845     case UnscaledNarrowOop:
 846       return "32-bit";
 847     case ZeroBasedNarrowOop:
 848       return "Zero based";
 849     case DisjointBaseNarrowOop:
 850       return "Non-zero disjoint base";
 851     case HeapBasedNarrowOop:
 852       return "Non-zero based";
 853   }
 854 
 855   ShouldNotReachHere();
 856   return "";
 857 }
 858 
 859 
 860 Universe::NARROW_OOP_MODE Universe::narrow_oop_mode() {
 861   if (narrow_oop_base_disjoint()) {
 862     return DisjointBaseNarrowOop;
 863   }
 864 
 865   if (narrow_oop_base() != 0) {
 866     return HeapBasedNarrowOop;
 867   }
 868 
 869   if (narrow_oop_shift() != 0) {
 870     return ZeroBasedNarrowOop;
 871   }
 872 
 873   return UnscaledNarrowOop;
 874 }
 875 
 876 
 877 void universe2_init() {
 878   EXCEPTION_MARK;
 879   Universe::genesis(CATCH);
 880 }
 881 
 882 
 883 bool universe_post_init() {
 884   assert(!is_init_completed(), "Error: initialization not yet completed!");
 885   Universe::_fully_initialized = true;
 886   EXCEPTION_MARK;
 887   { ResourceMark rm;
 888     Interpreter::initialize();      // needed for interpreter entry points
 889     if (!UseSharedSpaces) {
 890       HandleMark hm(THREAD);
 891       KlassHandle ok_h(THREAD, SystemDictionary::Object_klass());
 892       Universe::reinitialize_vtable_of(ok_h, CHECK_false);
 893       Universe::reinitialize_itables(CHECK_false);
 894     }
 895   }
 896 
 897   HandleMark hm(THREAD);
 898   Klass* k;
 899   instanceKlassHandle k_h;
 900     // Setup preallocated empty java.lang.Class array
 901     Universe::_the_empty_class_klass_array = oopFactory::new_objArray(SystemDictionary::Class_klass(), 0, CHECK_false);
 902 
 903     // Setup preallocated OutOfMemoryError errors
 904     k = SystemDictionary::resolve_or_fail(vmSymbols::java_lang_OutOfMemoryError(), true, CHECK_false);
 905     k_h = instanceKlassHandle(THREAD, k);
 906     Universe::_out_of_memory_error_java_heap = k_h->allocate_instance(CHECK_false);
 907     Universe::_out_of_memory_error_metaspace = k_h->allocate_instance(CHECK_false);
 908     Universe::_out_of_memory_error_class_metaspace = k_h->allocate_instance(CHECK_false);
 909     Universe::_out_of_memory_error_array_size = k_h->allocate_instance(CHECK_false);
 910     Universe::_out_of_memory_error_gc_overhead_limit =
 911       k_h->allocate_instance(CHECK_false);
 912     Universe::_out_of_memory_error_realloc_objects = k_h->allocate_instance(CHECK_false);
 913 
 914     // Setup preallocated cause message for delayed StackOverflowError
 915     if (StackReservedPages > 0) {
 916       Universe::_delayed_stack_overflow_error_message =
 917         java_lang_String::create_oop_from_str("Delayed StackOverflowError due to ReservedStackAccess annotated method", CHECK_false);
 918     }
 919 
 920     // Setup preallocated NullPointerException
 921     // (this is currently used for a cheap & dirty solution in compiler exception handling)
 922     k = SystemDictionary::resolve_or_fail(vmSymbols::java_lang_NullPointerException(), true, CHECK_false);
 923     Universe::_null_ptr_exception_instance = InstanceKlass::cast(k)->allocate_instance(CHECK_false);
 924     // Setup preallocated ArithmeticException
 925     // (this is currently used for a cheap & dirty solution in compiler exception handling)
 926     k = SystemDictionary::resolve_or_fail(vmSymbols::java_lang_ArithmeticException(), true, CHECK_false);
 927     Universe::_arithmetic_exception_instance = InstanceKlass::cast(k)->allocate_instance(CHECK_false);
 928     // Virtual Machine Error for when we get into a situation we can't resolve
 929     k = SystemDictionary::resolve_or_fail(
 930       vmSymbols::java_lang_VirtualMachineError(), true, CHECK_false);
 931     bool linked = InstanceKlass::cast(k)->link_class_or_fail(CHECK_false);
 932     if (!linked) {
 933       tty->print_cr("Unable to link/verify VirtualMachineError class");
 934       return false; // initialization failed
 935     }
 936     Universe::_virtual_machine_error_instance =
 937       InstanceKlass::cast(k)->allocate_instance(CHECK_false);
 938 
 939     Universe::_vm_exception = InstanceKlass::cast(k)->allocate_instance(CHECK_false);
 940 
 941   if (!DumpSharedSpaces) {
 942     // These are the only Java fields that are currently set during shared space dumping.
 943     // We prefer to not handle this generally, so we always reinitialize these detail messages.
 944     Handle msg = java_lang_String::create_from_str("Java heap space", CHECK_false);
 945     java_lang_Throwable::set_message(Universe::_out_of_memory_error_java_heap, msg());
 946 
 947     msg = java_lang_String::create_from_str("Metaspace", CHECK_false);
 948     java_lang_Throwable::set_message(Universe::_out_of_memory_error_metaspace, msg());
 949     msg = java_lang_String::create_from_str("Compressed class space", CHECK_false);
 950     java_lang_Throwable::set_message(Universe::_out_of_memory_error_class_metaspace, msg());
 951 
 952     msg = java_lang_String::create_from_str("Requested array size exceeds VM limit", CHECK_false);
 953     java_lang_Throwable::set_message(Universe::_out_of_memory_error_array_size, msg());
 954 
 955     msg = java_lang_String::create_from_str("GC overhead limit exceeded", CHECK_false);
 956     java_lang_Throwable::set_message(Universe::_out_of_memory_error_gc_overhead_limit, msg());
 957 
 958     msg = java_lang_String::create_from_str("Java heap space: failed reallocation of scalar replaced objects", CHECK_false);
 959     java_lang_Throwable::set_message(Universe::_out_of_memory_error_realloc_objects, msg());
 960 
 961     msg = java_lang_String::create_from_str("/ by zero", CHECK_false);
 962     java_lang_Throwable::set_message(Universe::_arithmetic_exception_instance, msg());
 963 
 964     // Setup the array of errors that have preallocated backtrace
 965     k = Universe::_out_of_memory_error_java_heap->klass();
 966     assert(k->name() == vmSymbols::java_lang_OutOfMemoryError(), "should be out of memory error");
 967     k_h = instanceKlassHandle(THREAD, k);
 968 
 969     int len = (StackTraceInThrowable) ? (int)PreallocatedOutOfMemoryErrorCount : 0;
 970     Universe::_preallocated_out_of_memory_error_array = oopFactory::new_objArray(k_h(), len, CHECK_false);
 971     for (int i=0; i<len; i++) {
 972       oop err = k_h->allocate_instance(CHECK_false);
 973       Handle err_h = Handle(THREAD, err);
 974       java_lang_Throwable::allocate_backtrace(err_h, CHECK_false);
 975       Universe::preallocated_out_of_memory_errors()->obj_at_put(i, err_h());
 976     }
 977     Universe::_preallocated_out_of_memory_error_avail_count = (jint)len;
 978   }
 979 
 980 
 981   // Setup static method for registering finalizers
 982   // The finalizer klass must be linked before looking up the method, in
 983   // case it needs to get rewritten.
 984   SystemDictionary::Finalizer_klass()->link_class(CHECK_false);
 985   Method* m = SystemDictionary::Finalizer_klass()->find_method(
 986                                   vmSymbols::register_method_name(),
 987                                   vmSymbols::register_method_signature());
 988   if (m == NULL || !m->is_static()) {
 989     tty->print_cr("Unable to link/verify Finalizer.register method");
 990     return false; // initialization failed (cannot throw exception yet)
 991   }
 992   Universe::_finalizer_register_cache->init(
 993     SystemDictionary::Finalizer_klass(), m);
 994 
 995   SystemDictionary::internal_Unsafe_klass()->link_class(CHECK_false);
 996   m = SystemDictionary::internal_Unsafe_klass()->find_method(
 997                                   vmSymbols::throwIllegalAccessError_name(),
 998                                   vmSymbols::void_method_signature());
 999   if (m != NULL && !m->is_static()) {
1000     // Note null is okay; this method is used in itables, and if it is null,
1001     // then AbstractMethodError is thrown instead.
1002     tty->print_cr("Unable to link/verify Unsafe.throwIllegalAccessError method");
1003     return false; // initialization failed (cannot throw exception yet)
1004   }
1005   Universe::_throw_illegal_access_error_cache->init(
1006     SystemDictionary::internal_Unsafe_klass(), m);
1007 
1008   // Setup method for registering loaded classes in class loader vector
1009   SystemDictionary::ClassLoader_klass()->link_class(CHECK_false);
1010   m = SystemDictionary::ClassLoader_klass()->find_method(vmSymbols::addClass_name(), vmSymbols::class_void_signature());
1011   if (m == NULL || m->is_static()) {
1012     tty->print_cr("Unable to link/verify ClassLoader.addClass method");
1013     return false; // initialization failed (cannot throw exception yet)
1014   }
1015   Universe::_loader_addClass_cache->init(
1016     SystemDictionary::ClassLoader_klass(), m);
1017 
1018   // Setup method for checking protection domain
1019   SystemDictionary::ProtectionDomain_klass()->link_class(CHECK_false);
1020   m = SystemDictionary::ProtectionDomain_klass()->
1021             find_method(vmSymbols::impliesCreateAccessControlContext_name(),
1022                         vmSymbols::void_boolean_signature());
1023   // Allow NULL which should only happen with bootstrapping.
1024   if (m != NULL) {
1025     if (m->is_static()) {
1026       // NoSuchMethodException doesn't actually work because it tries to run the
1027       // <init> function before java_lang_Class is linked. Print error and exit.
1028       tty->print_cr("ProtectionDomain.impliesCreateAccessControlContext() has the wrong linkage");
1029       return false; // initialization failed
1030     }
1031     Universe::_pd_implies_cache->init(
1032       SystemDictionary::ProtectionDomain_klass(), m);
1033   }
1034 
1035   // Setup method for stack walking
1036   InstanceKlass::cast(SystemDictionary::AbstractStackWalker_klass())->link_class(CHECK_false);
1037   m = InstanceKlass::cast(SystemDictionary::AbstractStackWalker_klass())->
1038             find_method(vmSymbols::doStackWalk_name(),
1039                         vmSymbols::doStackWalk_signature());
1040   // Allow NULL which should only happen with bootstrapping.
1041   if (m != NULL) {
1042     Universe::_do_stack_walk_cache->init(
1043       SystemDictionary::AbstractStackWalker_klass(), m);
1044   }
1045 
1046   // This needs to be done before the first scavenge/gc, since
1047   // it's an input to soft ref clearing policy.
1048   {
1049     MutexLocker x(Heap_lock);
1050     Universe::update_heap_info_at_gc();
1051   }
1052 
1053   // ("weak") refs processing infrastructure initialization
1054   Universe::heap()->post_initialize();
1055 
1056   // Initialize performance counters for metaspaces
1057   MetaspaceCounters::initialize_performance_counters();
1058   CompressedClassSpaceCounters::initialize_performance_counters();
1059 
1060   MemoryService::add_metaspace_memory_pools();
1061 
1062   MemoryService::set_universe_heap(Universe::heap());
1063 #if INCLUDE_CDS
1064   SharedClassUtil::initialize(CHECK_false);
1065 #endif
1066   return true;
1067 }
1068 
1069 
1070 void Universe::compute_base_vtable_size() {
1071   _base_vtable_size = ClassLoader::compute_Object_vtable();
1072 }
1073 
1074 void Universe::print_on(outputStream* st) {
1075   st->print_cr("Heap");
1076   heap()->print_on(st);
1077 }
1078 
1079 void Universe::print_heap_at_SIGBREAK() {
1080   if (PrintHeapAtSIGBREAK) {
1081     MutexLocker hl(Heap_lock);
1082     print_on(tty);
1083     tty->cr();
1084     tty->flush();
1085   }
1086 }
1087 
1088 void Universe::print_heap_before_gc() {
1089   LogHandle(gc, heap) log;
1090   if (log.is_trace()) {
1091     log.trace("Heap before GC invocations=%u (full %u):", heap()->total_collections(), heap()->total_full_collections());
1092     ResourceMark rm;
1093     heap()->print_on(log.trace_stream());
1094   }
1095 }
1096 
1097 void Universe::print_heap_after_gc() {
1098   LogHandle(gc, heap) log;
1099   if (log.is_trace()) {
1100     log.trace("Heap after GC invocations=%u (full %u):", heap()->total_collections(), heap()->total_full_collections());
1101     ResourceMark rm;
1102     heap()->print_on(log.trace_stream());
1103   }
1104 }
1105 
1106 void Universe::verify(VerifyOption option, const char* prefix) {
1107   // The use of _verify_in_progress is a temporary work around for
1108   // 6320749.  Don't bother with a creating a class to set and clear
1109   // it since it is only used in this method and the control flow is
1110   // straight forward.
1111   _verify_in_progress = true;
1112 
1113   COMPILER2_PRESENT(
1114     assert(!DerivedPointerTable::is_active(),
1115          "DPT should not be active during verification "
1116          "(of thread stacks below)");
1117   )
1118 
1119   ResourceMark rm;
1120   HandleMark hm;  // Handles created during verification can be zapped
1121   _verify_count++;
1122 
1123   FormatBuffer<> title("Verifying %s", prefix);
1124   GCTraceTime(Info, gc, verify) tm(title.buffer());
1125   log_debug(gc, verify)("Threads");
1126   Threads::verify();
1127   log_debug(gc, verify)("Heap");
1128   heap()->verify(option);
1129   log_debug(gc, verify)("SymbolTable");
1130   SymbolTable::verify();
1131   log_debug(gc, verify)("StringTable");
1132   StringTable::verify();
1133   {
1134     MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
1135     log_debug(gc, verify)("CodeCache");
1136     CodeCache::verify();
1137   }
1138   log_debug(gc, verify)("SystemDictionary");
1139   SystemDictionary::verify();
1140 #ifndef PRODUCT
1141   log_debug(gc, verify)("ClassLoaderDataGraph");
1142   ClassLoaderDataGraph::verify();
1143 #endif
1144   log_debug(gc, verify)("MetaspaceAux");
1145   MetaspaceAux::verify_free_chunks();
1146   log_debug(gc, verify)("JNIHandles");
1147   JNIHandles::verify();
1148   log_debug(gc, verify)("C-heap");
1149   os::check_heap();
1150   log_debug(gc, verify)("CodeCache Oops");
1151   CodeCache::verify_oops();
1152 
1153   _verify_in_progress = false;
1154 }
1155 
1156 
1157 #ifndef PRODUCT
1158 void Universe::calculate_verify_data(HeapWord* low_boundary, HeapWord* high_boundary) {
1159   assert(low_boundary < high_boundary, "bad interval");
1160 
1161   // decide which low-order bits we require to be clear:
1162   size_t alignSize = MinObjAlignmentInBytes;
1163   size_t min_object_size = CollectedHeap::min_fill_size();
1164 
1165   // make an inclusive limit:
1166   uintptr_t max = (uintptr_t)high_boundary - min_object_size*wordSize;
1167   uintptr_t min = (uintptr_t)low_boundary;
1168   assert(min < max, "bad interval");
1169   uintptr_t diff = max ^ min;
1170 
1171   // throw away enough low-order bits to make the diff vanish
1172   uintptr_t mask = (uintptr_t)(-1);
1173   while ((mask & diff) != 0)
1174     mask <<= 1;
1175   uintptr_t bits = (min & mask);
1176   assert(bits == (max & mask), "correct mask");
1177   // check an intermediate value between min and max, just to make sure:
1178   assert(bits == ((min + (max-min)/2) & mask), "correct mask");
1179 
1180   // require address alignment, too:
1181   mask |= (alignSize - 1);
1182 
1183   if (!(_verify_oop_mask == 0 && _verify_oop_bits == (uintptr_t)-1)) {
1184     assert(_verify_oop_mask == mask && _verify_oop_bits == bits, "mask stability");
1185   }
1186   _verify_oop_mask = mask;
1187   _verify_oop_bits = bits;
1188 }
1189 
1190 // Oop verification (see MacroAssembler::verify_oop)
1191 
1192 uintptr_t Universe::verify_oop_mask() {
1193   MemRegion m = heap()->reserved_region();
1194   calculate_verify_data(m.start(), m.end());
1195   return _verify_oop_mask;
1196 }
1197 
1198 uintptr_t Universe::verify_oop_bits() {
1199   MemRegion m = heap()->reserved_region();
1200   calculate_verify_data(m.start(), m.end());
1201   return _verify_oop_bits;
1202 }
1203 
1204 uintptr_t Universe::verify_mark_mask() {
1205   return markOopDesc::lock_mask_in_place;
1206 }
1207 
1208 uintptr_t Universe::verify_mark_bits() {
1209   intptr_t mask = verify_mark_mask();
1210   intptr_t bits = (intptr_t)markOopDesc::prototype();
1211   assert((bits & ~mask) == 0, "no stray header bits");
1212   return bits;
1213 }
1214 #endif // PRODUCT
1215 
1216 
1217 void Universe::compute_verify_oop_data() {
1218   verify_oop_mask();
1219   verify_oop_bits();
1220   verify_mark_mask();
1221   verify_mark_bits();
1222 }
1223 
1224 
1225 void LatestMethodCache::init(Klass* k, Method* m) {
1226   if (!UseSharedSpaces) {
1227     _klass = k;
1228   }
1229 #ifndef PRODUCT
1230   else {
1231     // sharing initilization should have already set up _klass
1232     assert(_klass != NULL, "just checking");
1233   }
1234 #endif
1235 
1236   _method_idnum = m->method_idnum();
1237   assert(_method_idnum >= 0, "sanity check");
1238 }
1239 
1240 
1241 Method* LatestMethodCache::get_method() {
1242   if (klass() == NULL) return NULL;
1243   InstanceKlass* ik = InstanceKlass::cast(klass());
1244   Method* m = ik->method_with_idnum(method_idnum());
1245   assert(m != NULL, "sanity check");
1246   return m;
1247 }
1248 
1249 
1250 #ifdef ASSERT
1251 // Release dummy object(s) at bottom of heap
1252 bool Universe::release_fullgc_alot_dummy() {
1253   MutexLocker ml(FullGCALot_lock);
1254   if (_fullgc_alot_dummy_array != NULL) {
1255     if (_fullgc_alot_dummy_next >= _fullgc_alot_dummy_array->length()) {
1256       // No more dummies to release, release entire array instead
1257       _fullgc_alot_dummy_array = NULL;
1258       return false;
1259     }
1260     if (!UseConcMarkSweepGC) {
1261       // Release dummy at bottom of old generation
1262       _fullgc_alot_dummy_array->obj_at_put(_fullgc_alot_dummy_next++, NULL);
1263     }
1264     // Release dummy at bottom of permanent generation
1265     _fullgc_alot_dummy_array->obj_at_put(_fullgc_alot_dummy_next++, NULL);
1266   }
1267   return true;
1268 }
1269 
1270 #endif // ASSERT