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Java example source code file (universe.cpp)

This example Java source code file (universe.cpp) is included in the alvinalexander.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" TM.

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Java - Java tags/keywords

check, check_false, include_all_gcs, instanceklass::cast, klass, latestmethodcache, metadatafactory\:\:new_array, null, oopencodingheapmax, resourcemark, typearrayklass\:\:create_klass, unscalednarrowoop, usecompressedoops, usesharedspaces

The universe.cpp Java example source code

/*
 * Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 *
 */

#include "precompiled.hpp"
#include "classfile/classLoader.hpp"
#include "classfile/classLoaderData.hpp"
#include "classfile/javaClasses.hpp"
#include "classfile/symbolTable.hpp"
#include "classfile/systemDictionary.hpp"
#include "classfile/vmSymbols.hpp"
#include "code/codeCache.hpp"
#include "code/dependencies.hpp"
#include "gc_interface/collectedHeap.inline.hpp"
#include "interpreter/interpreter.hpp"
#include "memory/cardTableModRefBS.hpp"
#include "memory/gcLocker.inline.hpp"
#include "memory/genCollectedHeap.hpp"
#include "memory/genRemSet.hpp"
#include "memory/generation.hpp"
#include "memory/metadataFactory.hpp"
#include "memory/metaspaceShared.hpp"
#include "memory/oopFactory.hpp"
#include "memory/space.hpp"
#include "memory/universe.hpp"
#include "memory/universe.inline.hpp"
#include "oops/constantPool.hpp"
#include "oops/instanceClassLoaderKlass.hpp"
#include "oops/instanceKlass.hpp"
#include "oops/instanceMirrorKlass.hpp"
#include "oops/instanceRefKlass.hpp"
#include "oops/oop.inline.hpp"
#include "oops/typeArrayKlass.hpp"
#include "prims/jvmtiRedefineClassesTrace.hpp"
#include "runtime/arguments.hpp"
#include "runtime/deoptimization.hpp"
#include "runtime/fprofiler.hpp"
#include "runtime/handles.inline.hpp"
#include "runtime/init.hpp"
#include "runtime/java.hpp"
#include "runtime/javaCalls.hpp"
#include "runtime/sharedRuntime.hpp"
#include "runtime/synchronizer.hpp"
#include "runtime/thread.inline.hpp"
#include "runtime/timer.hpp"
#include "runtime/vm_operations.hpp"
#include "services/memoryService.hpp"
#include "utilities/copy.hpp"
#include "utilities/events.hpp"
#include "utilities/hashtable.inline.hpp"
#include "utilities/preserveException.hpp"
#include "utilities/macros.hpp"
#if INCLUDE_ALL_GCS
#include "gc_implementation/concurrentMarkSweep/cmsAdaptiveSizePolicy.hpp"
#include "gc_implementation/concurrentMarkSweep/cmsCollectorPolicy.hpp"
#include "gc_implementation/g1/g1CollectedHeap.inline.hpp"
#include "gc_implementation/g1/g1CollectorPolicy.hpp"
#include "gc_implementation/parallelScavenge/parallelScavengeHeap.hpp"
#endif // INCLUDE_ALL_GCS

// Known objects
Klass* Universe::_boolArrayKlassObj                 = NULL;
Klass* Universe::_byteArrayKlassObj                 = NULL;
Klass* Universe::_charArrayKlassObj                 = NULL;
Klass* Universe::_intArrayKlassObj                  = NULL;
Klass* Universe::_shortArrayKlassObj                = NULL;
Klass* Universe::_longArrayKlassObj                 = NULL;
Klass* Universe::_singleArrayKlassObj               = NULL;
Klass* Universe::_doubleArrayKlassObj               = NULL;
Klass* Universe::_typeArrayKlassObjs[T_VOID+1]      = { NULL /*, NULL...*/ };
Klass* Universe::_objectArrayKlassObj               = NULL;
oop Universe::_int_mirror                             = NULL;
oop Universe::_float_mirror                           = NULL;
oop Universe::_double_mirror                          = NULL;
oop Universe::_byte_mirror                            = NULL;
oop Universe::_bool_mirror                            = NULL;
oop Universe::_char_mirror                            = NULL;
oop Universe::_long_mirror                            = NULL;
oop Universe::_short_mirror                           = NULL;
oop Universe::_void_mirror                            = NULL;
oop Universe::_mirrors[T_VOID+1]                      = { NULL /*, NULL...*/ };
oop Universe::_main_thread_group                      = NULL;
oop Universe::_system_thread_group                    = NULL;
objArrayOop Universe::_the_empty_class_klass_array    = NULL;
Array<Klass*>* Universe::_the_array_interfaces_array = NULL;
oop Universe::_the_null_string                        = NULL;
oop Universe::_the_min_jint_string                   = NULL;
LatestMethodCache* Universe::_finalizer_register_cache = NULL;
LatestMethodCache* Universe::_loader_addClass_cache    = NULL;
LatestMethodCache* Universe::_pd_implies_cache         = NULL;
oop Universe::_out_of_memory_error_java_heap          = NULL;
oop Universe::_out_of_memory_error_metaspace          = NULL;
oop Universe::_out_of_memory_error_class_metaspace    = NULL;
oop Universe::_out_of_memory_error_array_size         = NULL;
oop Universe::_out_of_memory_error_gc_overhead_limit  = NULL;
objArrayOop Universe::_preallocated_out_of_memory_error_array = NULL;
volatile jint Universe::_preallocated_out_of_memory_error_avail_count = 0;
bool Universe::_verify_in_progress                    = false;
oop Universe::_null_ptr_exception_instance            = NULL;
oop Universe::_arithmetic_exception_instance          = NULL;
oop Universe::_virtual_machine_error_instance         = NULL;
oop Universe::_vm_exception                           = NULL;
Method* Universe::_throw_illegal_access_error         = NULL;
Array<int>* Universe::_the_empty_int_array            = NULL;
Array<u2>* Universe::_the_empty_short_array           = NULL;
Array<Klass*>* Universe::_the_empty_klass_array     = NULL;
Array<Method*>* Universe::_the_empty_method_array   = NULL;

// These variables are guarded by FullGCALot_lock.
debug_only(objArrayOop Universe::_fullgc_alot_dummy_array = NULL;)
debug_only(int Universe::_fullgc_alot_dummy_next      = 0;)

// Heap
int             Universe::_verify_count = 0;

int             Universe::_base_vtable_size = 0;
bool            Universe::_bootstrapping = false;
bool            Universe::_fully_initialized = false;

size_t          Universe::_heap_capacity_at_last_gc;
size_t          Universe::_heap_used_at_last_gc = 0;

CollectedHeap*  Universe::_collectedHeap = NULL;

NarrowPtrStruct Universe::_narrow_oop = { NULL, 0, true };
NarrowPtrStruct Universe::_narrow_klass = { NULL, 0, true };
address Universe::_narrow_ptrs_base;

void Universe::basic_type_classes_do(void f(Klass*)) {
  f(boolArrayKlassObj());
  f(byteArrayKlassObj());
  f(charArrayKlassObj());
  f(intArrayKlassObj());
  f(shortArrayKlassObj());
  f(longArrayKlassObj());
  f(singleArrayKlassObj());
  f(doubleArrayKlassObj());
}

void Universe::oops_do(OopClosure* f, bool do_all) {

  f->do_oop((oop*) &_int_mirror);
  f->do_oop((oop*) &_float_mirror);
  f->do_oop((oop*) &_double_mirror);
  f->do_oop((oop*) &_byte_mirror);
  f->do_oop((oop*) &_bool_mirror);
  f->do_oop((oop*) &_char_mirror);
  f->do_oop((oop*) &_long_mirror);
  f->do_oop((oop*) &_short_mirror);
  f->do_oop((oop*) &_void_mirror);

  for (int i = T_BOOLEAN; i < T_VOID+1; i++) {
    f->do_oop((oop*) &_mirrors[i]);
  }
  assert(_mirrors[0] == NULL && _mirrors[T_BOOLEAN - 1] == NULL, "checking");

  f->do_oop((oop*)&_the_empty_class_klass_array);
  f->do_oop((oop*)&_the_null_string);
  f->do_oop((oop*)&_the_min_jint_string);
  f->do_oop((oop*)&_out_of_memory_error_java_heap);
  f->do_oop((oop*)&_out_of_memory_error_metaspace);
  f->do_oop((oop*)&_out_of_memory_error_class_metaspace);
  f->do_oop((oop*)&_out_of_memory_error_array_size);
  f->do_oop((oop*)&_out_of_memory_error_gc_overhead_limit);
    f->do_oop((oop*)&_preallocated_out_of_memory_error_array);
  f->do_oop((oop*)&_null_ptr_exception_instance);
  f->do_oop((oop*)&_arithmetic_exception_instance);
  f->do_oop((oop*)&_virtual_machine_error_instance);
  f->do_oop((oop*)&_main_thread_group);
  f->do_oop((oop*)&_system_thread_group);
  f->do_oop((oop*)&_vm_exception);
  debug_only(f->do_oop((oop*)&_fullgc_alot_dummy_array);)
}

// Serialize metadata in and out of CDS archive, not oops.
void Universe::serialize(SerializeClosure* f, bool do_all) {

  f->do_ptr((void**)&_boolArrayKlassObj);
  f->do_ptr((void**)&_byteArrayKlassObj);
  f->do_ptr((void**)&_charArrayKlassObj);
  f->do_ptr((void**)&_intArrayKlassObj);
  f->do_ptr((void**)&_shortArrayKlassObj);
  f->do_ptr((void**)&_longArrayKlassObj);
  f->do_ptr((void**)&_singleArrayKlassObj);
  f->do_ptr((void**)&_doubleArrayKlassObj);
  f->do_ptr((void**)&_objectArrayKlassObj);

  {
    for (int i = 0; i < T_VOID+1; i++) {
      if (_typeArrayKlassObjs[i] != NULL) {
        assert(i >= T_BOOLEAN, "checking");
        f->do_ptr((void**)&_typeArrayKlassObjs[i]);
      } else if (do_all) {
        f->do_ptr((void**)&_typeArrayKlassObjs[i]);
      }
    }
  }

  f->do_ptr((void**)&_the_array_interfaces_array);
  f->do_ptr((void**)&_the_empty_int_array);
  f->do_ptr((void**)&_the_empty_short_array);
  f->do_ptr((void**)&_the_empty_method_array);
  f->do_ptr((void**)&_the_empty_klass_array);
  _finalizer_register_cache->serialize(f);
  _loader_addClass_cache->serialize(f);
  _pd_implies_cache->serialize(f);
}

void Universe::check_alignment(uintx size, uintx alignment, const char* name) {
  if (size < alignment || size % alignment != 0) {
    vm_exit_during_initialization(
      err_msg("Size of %s (" UINTX_FORMAT " bytes) must be aligned to " UINTX_FORMAT " bytes", name, size, alignment));
  }
}

void initialize_basic_type_klass(Klass* k, TRAPS) {
  Klass* ok = SystemDictionary::Object_klass();
  if (UseSharedSpaces) {
    assert(k->super() == ok, "u3");
    k->restore_unshareable_info(CHECK);
  } else {
    k->initialize_supers(ok, CHECK);
  }
  k->append_to_sibling_list();
}

void Universe::genesis(TRAPS) {
  ResourceMark rm;

  { FlagSetting fs(_bootstrapping, true);

    { MutexLocker mc(Compile_lock);

      // determine base vtable size; without that we cannot create the array klasses
      compute_base_vtable_size();

      if (!UseSharedSpaces) {
        _boolArrayKlassObj      = TypeArrayKlass::create_klass(T_BOOLEAN, sizeof(jboolean), CHECK);
        _charArrayKlassObj      = TypeArrayKlass::create_klass(T_CHAR,    sizeof(jchar),    CHECK);
        _singleArrayKlassObj    = TypeArrayKlass::create_klass(T_FLOAT,   sizeof(jfloat),   CHECK);
        _doubleArrayKlassObj    = TypeArrayKlass::create_klass(T_DOUBLE,  sizeof(jdouble),  CHECK);
        _byteArrayKlassObj      = TypeArrayKlass::create_klass(T_BYTE,    sizeof(jbyte),    CHECK);
        _shortArrayKlassObj     = TypeArrayKlass::create_klass(T_SHORT,   sizeof(jshort),   CHECK);
        _intArrayKlassObj       = TypeArrayKlass::create_klass(T_INT,     sizeof(jint),     CHECK);
        _longArrayKlassObj      = TypeArrayKlass::create_klass(T_LONG,    sizeof(jlong),    CHECK);

        _typeArrayKlassObjs[T_BOOLEAN] = _boolArrayKlassObj;
        _typeArrayKlassObjs[T_CHAR]    = _charArrayKlassObj;
        _typeArrayKlassObjs[T_FLOAT]   = _singleArrayKlassObj;
        _typeArrayKlassObjs[T_DOUBLE]  = _doubleArrayKlassObj;
        _typeArrayKlassObjs[T_BYTE]    = _byteArrayKlassObj;
        _typeArrayKlassObjs[T_SHORT]   = _shortArrayKlassObj;
        _typeArrayKlassObjs[T_INT]     = _intArrayKlassObj;
        _typeArrayKlassObjs[T_LONG]    = _longArrayKlassObj;

        ClassLoaderData* null_cld = ClassLoaderData::the_null_class_loader_data();

        _the_array_interfaces_array = MetadataFactory::new_array<Klass*>(null_cld, 2, NULL, CHECK);
        _the_empty_int_array        = MetadataFactory::new_array<int>(null_cld, 0, CHECK);
        _the_empty_short_array      = MetadataFactory::new_array<u2>(null_cld, 0, CHECK);
        _the_empty_method_array     = MetadataFactory::new_array<Method*>(null_cld, 0, CHECK);
        _the_empty_klass_array      = MetadataFactory::new_array<Klass*>(null_cld, 0, CHECK);
      }
    }

    vmSymbols::initialize(CHECK);

    SystemDictionary::initialize(CHECK);

    Klass* ok = SystemDictionary::Object_klass();

    _the_null_string            = StringTable::intern("null", CHECK);
    _the_min_jint_string       = StringTable::intern("-2147483648", CHECK);

    if (UseSharedSpaces) {
      // Verify shared interfaces array.
      assert(_the_array_interfaces_array->at(0) ==
             SystemDictionary::Cloneable_klass(), "u3");
      assert(_the_array_interfaces_array->at(1) ==
             SystemDictionary::Serializable_klass(), "u3");
    } else {
      // Set up shared interfaces array.  (Do this before supers are set up.)
      _the_array_interfaces_array->at_put(0, SystemDictionary::Cloneable_klass());
      _the_array_interfaces_array->at_put(1, SystemDictionary::Serializable_klass());
    }

    initialize_basic_type_klass(boolArrayKlassObj(), CHECK);
    initialize_basic_type_klass(charArrayKlassObj(), CHECK);
    initialize_basic_type_klass(singleArrayKlassObj(), CHECK);
    initialize_basic_type_klass(doubleArrayKlassObj(), CHECK);
    initialize_basic_type_klass(byteArrayKlassObj(), CHECK);
    initialize_basic_type_klass(shortArrayKlassObj(), CHECK);
    initialize_basic_type_klass(intArrayKlassObj(), CHECK);
    initialize_basic_type_klass(longArrayKlassObj(), CHECK);
  } // end of core bootstrapping

  // Maybe this could be lifted up now that object array can be initialized
  // during the bootstrapping.

  // OLD
  // Initialize _objectArrayKlass after core bootstraping to make
  // sure the super class is set up properly for _objectArrayKlass.
  // ---
  // NEW
  // Since some of the old system object arrays have been converted to
  // ordinary object arrays, _objectArrayKlass will be loaded when
  // SystemDictionary::initialize(CHECK); is run. See the extra check
  // for Object_klass_loaded in objArrayKlassKlass::allocate_objArray_klass_impl.
  _objectArrayKlassObj = InstanceKlass::
    cast(SystemDictionary::Object_klass())->array_klass(1, CHECK);
  // OLD
  // Add the class to the class hierarchy manually to make sure that
  // its vtable is initialized after core bootstrapping is completed.
  // ---
  // New
  // Have already been initialized.
  _objectArrayKlassObj->append_to_sibling_list();

  // Compute is_jdk version flags.
  // Only 1.3 or later has the java.lang.Shutdown class.
  // Only 1.4 or later has the java.lang.CharSequence interface.
  // Only 1.5 or later has the java.lang.management.MemoryUsage class.
  if (JDK_Version::is_partially_initialized()) {
    uint8_t jdk_version;
    Klass* k = SystemDictionary::resolve_or_null(
        vmSymbols::java_lang_management_MemoryUsage(), THREAD);
    CLEAR_PENDING_EXCEPTION; // ignore exceptions
    if (k == NULL) {
      k = SystemDictionary::resolve_or_null(
          vmSymbols::java_lang_CharSequence(), THREAD);
      CLEAR_PENDING_EXCEPTION; // ignore exceptions
      if (k == NULL) {
        k = SystemDictionary::resolve_or_null(
            vmSymbols::java_lang_Shutdown(), THREAD);
        CLEAR_PENDING_EXCEPTION; // ignore exceptions
        if (k == NULL) {
          jdk_version = 2;
        } else {
          jdk_version = 3;
        }
      } else {
        jdk_version = 4;
      }
    } else {
      jdk_version = 5;
    }
    JDK_Version::fully_initialize(jdk_version);
  }

  #ifdef ASSERT
  if (FullGCALot) {
    // Allocate an array of dummy objects.
    // We'd like these to be at the bottom of the old generation,
    // so that when we free one and then collect,
    // (almost) the whole heap moves
    // and we find out if we actually update all the oops correctly.
    // But we can't allocate directly in the old generation,
    // so we allocate wherever, and hope that the first collection
    // moves these objects to the bottom of the old generation.
    // We can allocate directly in the permanent generation, so we do.
    int size;
    if (UseConcMarkSweepGC) {
      warning("Using +FullGCALot with concurrent mark sweep gc "
              "will not force all objects to relocate");
      size = FullGCALotDummies;
    } else {
      size = FullGCALotDummies * 2;
    }
    objArrayOop    naked_array = oopFactory::new_objArray(SystemDictionary::Object_klass(), size, CHECK);
    objArrayHandle dummy_array(THREAD, naked_array);
    int i = 0;
    while (i < size) {
        // Allocate dummy in old generation
      oop dummy = InstanceKlass::cast(SystemDictionary::Object_klass())->allocate_instance(CHECK);
      dummy_array->obj_at_put(i++, dummy);
    }
    {
      // Only modify the global variable inside the mutex.
      // If we had a race to here, the other dummy_array instances
      // and their elements just get dropped on the floor, which is fine.
      MutexLocker ml(FullGCALot_lock);
      if (_fullgc_alot_dummy_array == NULL) {
        _fullgc_alot_dummy_array = dummy_array();
      }
    }
    assert(i == _fullgc_alot_dummy_array->length(), "just checking");
  }
  #endif

  // Initialize dependency array for null class loader
  ClassLoaderData::the_null_class_loader_data()->init_dependencies(CHECK);

}

// CDS support for patching vtables in metadata in the shared archive.
// All types inherited from Metadata have vtables, but not types inherited
// from MetaspaceObj, because the latter does not have virtual functions.
// If the metadata type has a vtable, it cannot be shared in the read-only
// section of the CDS archive, because the vtable pointer is patched.
static inline void add_vtable(void** list, int* n, void* o, int count) {
  guarantee((*n) < count, "vtable list too small");
  void* vtable = dereference_vptr(o);
  assert(*(void**)(vtable) != NULL, "invalid vtable");
  list[(*n)++] = vtable;
}

void Universe::init_self_patching_vtbl_list(void** list, int count) {
  int n = 0;
  { InstanceKlass o;          add_vtable(list, &n, &o, count); }
  { InstanceClassLoaderKlass o; add_vtable(list, &n, &o, count); }
  { InstanceMirrorKlass o;    add_vtable(list, &n, &o, count); }
  { InstanceRefKlass o;       add_vtable(list, &n, &o, count); }
  { TypeArrayKlass o;         add_vtable(list, &n, &o, count); }
  { ObjArrayKlass o;          add_vtable(list, &n, &o, count); }
  { Method o;                 add_vtable(list, &n, &o, count); }
  { ConstantPool o;           add_vtable(list, &n, &o, count); }
}

void Universe::initialize_basic_type_mirrors(TRAPS) {
    assert(_int_mirror==NULL, "basic type mirrors already initialized");
    _int_mirror     =
      java_lang_Class::create_basic_type_mirror("int",    T_INT, CHECK);
    _float_mirror   =
      java_lang_Class::create_basic_type_mirror("float",  T_FLOAT,   CHECK);
    _double_mirror  =
      java_lang_Class::create_basic_type_mirror("double", T_DOUBLE,  CHECK);
    _byte_mirror    =
      java_lang_Class::create_basic_type_mirror("byte",   T_BYTE, CHECK);
    _bool_mirror    =
      java_lang_Class::create_basic_type_mirror("boolean",T_BOOLEAN, CHECK);
    _char_mirror    =
      java_lang_Class::create_basic_type_mirror("char",   T_CHAR, CHECK);
    _long_mirror    =
      java_lang_Class::create_basic_type_mirror("long",   T_LONG, CHECK);
    _short_mirror   =
      java_lang_Class::create_basic_type_mirror("short",  T_SHORT,   CHECK);
    _void_mirror    =
      java_lang_Class::create_basic_type_mirror("void",   T_VOID, CHECK);

    _mirrors[T_INT]     = _int_mirror;
    _mirrors[T_FLOAT]   = _float_mirror;
    _mirrors[T_DOUBLE]  = _double_mirror;
    _mirrors[T_BYTE]    = _byte_mirror;
    _mirrors[T_BOOLEAN] = _bool_mirror;
    _mirrors[T_CHAR]    = _char_mirror;
    _mirrors[T_LONG]    = _long_mirror;
    _mirrors[T_SHORT]   = _short_mirror;
    _mirrors[T_VOID]    = _void_mirror;
  //_mirrors[T_OBJECT]  = InstanceKlass::cast(_object_klass)->java_mirror();
  //_mirrors[T_ARRAY]   = InstanceKlass::cast(_object_klass)->java_mirror();
}

void Universe::fixup_mirrors(TRAPS) {
  // Bootstrap problem: all classes gets a mirror (java.lang.Class instance) assigned eagerly,
  // but we cannot do that for classes created before java.lang.Class is loaded. Here we simply
  // walk over permanent objects created so far (mostly classes) and fixup their mirrors. Note
  // that the number of objects allocated at this point is very small.
  assert(SystemDictionary::Class_klass_loaded(), "java.lang.Class should be loaded");
  HandleMark hm(THREAD);
  // Cache the start of the static fields
  InstanceMirrorKlass::init_offset_of_static_fields();

  GrowableArray <Klass*>* list = java_lang_Class::fixup_mirror_list();
  int list_length = list->length();
  for (int i = 0; i < list_length; i++) {
    Klass* k = list->at(i);
    assert(k->is_klass(), "List should only hold classes");
    EXCEPTION_MARK;
    KlassHandle kh(THREAD, k);
    java_lang_Class::fixup_mirror(kh, CATCH);
}
  delete java_lang_Class::fixup_mirror_list();
  java_lang_Class::set_fixup_mirror_list(NULL);
}

static bool has_run_finalizers_on_exit = false;

void Universe::run_finalizers_on_exit() {
  if (has_run_finalizers_on_exit) return;
  has_run_finalizers_on_exit = true;

  // Called on VM exit. This ought to be run in a separate thread.
  if (TraceReferenceGC) tty->print_cr("Callback to run finalizers on exit");
  {
    PRESERVE_EXCEPTION_MARK;
    KlassHandle finalizer_klass(THREAD, SystemDictionary::Finalizer_klass());
    JavaValue result(T_VOID);
    JavaCalls::call_static(
      &result,
      finalizer_klass,
      vmSymbols::run_finalizers_on_exit_name(),
      vmSymbols::void_method_signature(),
      THREAD
    );
    // Ignore any pending exceptions
    CLEAR_PENDING_EXCEPTION;
  }
}


// initialize_vtable could cause gc if
// 1) we specified true to initialize_vtable and
// 2) this ran after gc was enabled
// In case those ever change we use handles for oops
void Universe::reinitialize_vtable_of(KlassHandle k_h, TRAPS) {
  // init vtable of k and all subclasses
  Klass* ko = k_h();
  klassVtable* vt = ko->vtable();
  if (vt) vt->initialize_vtable(false, CHECK);
  if (ko->oop_is_instance()) {
    InstanceKlass* ik = (InstanceKlass*)ko;
    for (KlassHandle s_h(THREAD, ik->subklass());
         s_h() != NULL;
         s_h = KlassHandle(THREAD, s_h()->next_sibling())) {
      reinitialize_vtable_of(s_h, CHECK);
    }
  }
}


void initialize_itable_for_klass(Klass* k, TRAPS) {
  InstanceKlass::cast(k)->itable()->initialize_itable(false, CHECK);
}


void Universe::reinitialize_itables(TRAPS) {
  SystemDictionary::classes_do(initialize_itable_for_klass, CHECK);

}


bool Universe::on_page_boundary(void* addr) {
  return ((uintptr_t) addr) % os::vm_page_size() == 0;
}


bool Universe::should_fill_in_stack_trace(Handle throwable) {
  // never attempt to fill in the stack trace of preallocated errors that do not have
  // backtrace. These errors are kept alive forever and may be "re-used" when all
  // preallocated errors with backtrace have been consumed. Also need to avoid
  // a potential loop which could happen if an out of memory occurs when attempting
  // to allocate the backtrace.
  return ((throwable() != Universe::_out_of_memory_error_java_heap) &&
          (throwable() != Universe::_out_of_memory_error_metaspace)  &&
          (throwable() != Universe::_out_of_memory_error_class_metaspace)  &&
          (throwable() != Universe::_out_of_memory_error_array_size) &&
          (throwable() != Universe::_out_of_memory_error_gc_overhead_limit));
}


oop Universe::gen_out_of_memory_error(oop default_err) {
  // generate an out of memory error:
  // - if there is a preallocated error with backtrace available then return it wth
  //   a filled in stack trace.
  // - if there are no preallocated errors with backtrace available then return
  //   an error without backtrace.
  int next;
  if (_preallocated_out_of_memory_error_avail_count > 0) {
    next = (int)Atomic::add(-1, &_preallocated_out_of_memory_error_avail_count);
    assert(next < (int)PreallocatedOutOfMemoryErrorCount, "avail count is corrupt");
  } else {
    next = -1;
  }
  if (next < 0) {
    // all preallocated errors have been used.
    // return default
    return default_err;
  } else {
    // get the error object at the slot and set set it to NULL so that the
    // array isn't keeping it alive anymore.
    oop exc = preallocated_out_of_memory_errors()->obj_at(next);
    assert(exc != NULL, "slot has been used already");
    preallocated_out_of_memory_errors()->obj_at_put(next, NULL);

    // use the message from the default error
    oop msg = java_lang_Throwable::message(default_err);
    assert(msg != NULL, "no message");
    java_lang_Throwable::set_message(exc, msg);

    // populate the stack trace and return it.
    java_lang_Throwable::fill_in_stack_trace_of_preallocated_backtrace(exc);
    return exc;
  }
}

intptr_t Universe::_non_oop_bits = 0;

void* Universe::non_oop_word() {
  // Neither the high bits nor the low bits of this value is allowed
  // to look like (respectively) the high or low bits of a real oop.
  //
  // High and low are CPU-specific notions, but low always includes
  // the low-order bit.  Since oops are always aligned at least mod 4,
  // setting the low-order bit will ensure that the low half of the
  // word will never look like that of a real oop.
  //
  // Using the OS-supplied non-memory-address word (usually 0 or -1)
  // will take care of the high bits, however many there are.

  if (_non_oop_bits == 0) {
    _non_oop_bits = (intptr_t)os::non_memory_address_word() | 1;
  }

  return (void*)_non_oop_bits;
}

jint universe_init() {
  assert(!Universe::_fully_initialized, "called after initialize_vtables");
  guarantee(1 << LogHeapWordSize == sizeof(HeapWord),
         "LogHeapWordSize is incorrect.");
  guarantee(sizeof(oop) >= sizeof(HeapWord), "HeapWord larger than oop?");
  guarantee(sizeof(oop) % sizeof(HeapWord) == 0,
            "oop size is not not a multiple of HeapWord size");
  TraceTime timer("Genesis", TraceStartupTime);
  GC_locker::lock();  // do not allow gc during bootstrapping
  JavaClasses::compute_hard_coded_offsets();

  jint status = Universe::initialize_heap();
  if (status != JNI_OK) {
    return status;
  }

  Metaspace::global_initialize();

  // Create memory for metadata.  Must be after initializing heap for
  // DumpSharedSpaces.
  ClassLoaderData::init_null_class_loader_data();

  // We have a heap so create the Method* caches before
  // Metaspace::initialize_shared_spaces() tries to populate them.
  Universe::_finalizer_register_cache = new LatestMethodCache();
  Universe::_loader_addClass_cache    = new LatestMethodCache();
  Universe::_pd_implies_cache         = new LatestMethodCache();

  if (UseSharedSpaces) {
    // Read the data structures supporting the shared spaces (shared
    // system dictionary, symbol table, etc.).  After that, access to
    // the file (other than the mapped regions) is no longer needed, and
    // the file is closed. Closing the file does not affect the
    // currently mapped regions.
    MetaspaceShared::initialize_shared_spaces();
    StringTable::create_table();
  } else {
    SymbolTable::create_table();
    StringTable::create_table();
    ClassLoader::create_package_info_table();
  }

  return JNI_OK;
}

// Choose the heap base address and oop encoding mode
// when compressed oops are used:
// Unscaled  - Use 32-bits oops without encoding when
//     NarrowOopHeapBaseMin + heap_size < 4Gb
// ZeroBased - Use zero based compressed oops with encoding when
//     NarrowOopHeapBaseMin + heap_size < 32Gb
// HeapBased - Use compressed oops with heap base + encoding.

// 4Gb
static const uint64_t UnscaledOopHeapMax = (uint64_t(max_juint) + 1);
// 32Gb
// OopEncodingHeapMax == UnscaledOopHeapMax << LogMinObjAlignmentInBytes;

char* Universe::preferred_heap_base(size_t heap_size, size_t alignment, NARROW_OOP_MODE mode) {
  assert(is_size_aligned((size_t)OopEncodingHeapMax, alignment), "Must be");
  assert(is_size_aligned((size_t)UnscaledOopHeapMax, alignment), "Must be");
  assert(is_size_aligned(heap_size, alignment), "Must be");

  uintx heap_base_min_address_aligned = align_size_up(HeapBaseMinAddress, alignment);

  size_t base = 0;
#ifdef _LP64
  if (UseCompressedOops) {
    assert(mode == UnscaledNarrowOop  ||
           mode == ZeroBasedNarrowOop ||
           mode == HeapBasedNarrowOop, "mode is invalid");
    const size_t total_size = heap_size + heap_base_min_address_aligned;
    // Return specified base for the first request.
    if (!FLAG_IS_DEFAULT(HeapBaseMinAddress) && (mode == UnscaledNarrowOop)) {
      base = heap_base_min_address_aligned;

    // If the total size is small enough to allow UnscaledNarrowOop then
    // just use UnscaledNarrowOop.
    } else if ((total_size <= OopEncodingHeapMax) && (mode != HeapBasedNarrowOop)) {
      if ((total_size <= UnscaledOopHeapMax) && (mode == UnscaledNarrowOop) &&
          (Universe::narrow_oop_shift() == 0)) {
        // Use 32-bits oops without encoding and
        // place heap's top on the 4Gb boundary
        base = (UnscaledOopHeapMax - heap_size);
      } else {
        // Can't reserve with NarrowOopShift == 0
        Universe::set_narrow_oop_shift(LogMinObjAlignmentInBytes);

        if (mode == UnscaledNarrowOop ||
            mode == ZeroBasedNarrowOop && total_size <= UnscaledOopHeapMax) {

          // Use zero based compressed oops with encoding and
          // place heap's top on the 32Gb boundary in case
          // total_size > 4Gb or failed to reserve below 4Gb.
          uint64_t heap_top = OopEncodingHeapMax;

          // For small heaps, save some space for compressed class pointer
          // space so it can be decoded with no base.
          if (UseCompressedClassPointers && !UseSharedSpaces &&
              OopEncodingHeapMax <= 32*G) {

            uint64_t class_space = align_size_up(CompressedClassSpaceSize, alignment);
            assert(is_size_aligned((size_t)OopEncodingHeapMax-class_space,
                   alignment), "difference must be aligned too");
            uint64_t new_top = OopEncodingHeapMax-class_space;

            if (total_size <= new_top) {
              heap_top = new_top;
            }
          }

          // Align base to the adjusted top of the heap
          base = heap_top - heap_size;
        }
      }
    } else {
      // UnscaledNarrowOop encoding didn't work, and no base was found for ZeroBasedOops or
      // HeapBasedNarrowOop encoding was requested.  So, can't reserve below 32Gb.
      Universe::set_narrow_oop_shift(LogMinObjAlignmentInBytes);
    }

    // Set narrow_oop_base and narrow_oop_use_implicit_null_checks
    // used in ReservedHeapSpace() constructors.
    // The final values will be set in initialize_heap() below.
    if ((base != 0) && ((base + heap_size) <= OopEncodingHeapMax)) {
      // Use zero based compressed oops
      Universe::set_narrow_oop_base(NULL);
      // Don't need guard page for implicit checks in indexed
      // addressing mode with zero based Compressed Oops.
      Universe::set_narrow_oop_use_implicit_null_checks(true);
    } else {
      // Set to a non-NULL value so the ReservedSpace ctor computes
      // the correct no-access prefix.
      // The final value will be set in initialize_heap() below.
      Universe::set_narrow_oop_base((address)UnscaledOopHeapMax);
#ifdef _WIN64
      if (UseLargePages) {
        // Cannot allocate guard pages for implicit checks in indexed
        // addressing mode when large pages are specified on windows.
        Universe::set_narrow_oop_use_implicit_null_checks(false);
      }
#endif //  _WIN64
    }
  }
#endif

  assert(is_ptr_aligned((char*)base, alignment), "Must be");
  return (char*)base; // also return NULL (don't care) for 32-bit VM
}

jint Universe::initialize_heap() {

  if (UseParallelGC) {
#if INCLUDE_ALL_GCS
    Universe::_collectedHeap = new ParallelScavengeHeap();
#else  // INCLUDE_ALL_GCS
    fatal("UseParallelGC not supported in this VM.");
#endif // INCLUDE_ALL_GCS

  } else if (UseG1GC) {
#if INCLUDE_ALL_GCS
    G1CollectorPolicy* g1p = new G1CollectorPolicy();
    g1p->initialize_all();
    G1CollectedHeap* g1h = new G1CollectedHeap(g1p);
    Universe::_collectedHeap = g1h;
#else  // INCLUDE_ALL_GCS
    fatal("UseG1GC not supported in java kernel vm.");
#endif // INCLUDE_ALL_GCS

  } else {
    GenCollectorPolicy *gc_policy;

    if (UseSerialGC) {
      gc_policy = new MarkSweepPolicy();
    } else if (UseConcMarkSweepGC) {
#if INCLUDE_ALL_GCS
      if (UseAdaptiveSizePolicy) {
        gc_policy = new ASConcurrentMarkSweepPolicy();
      } else {
        gc_policy = new ConcurrentMarkSweepPolicy();
      }
#else  // INCLUDE_ALL_GCS
    fatal("UseConcMarkSweepGC not supported in this VM.");
#endif // INCLUDE_ALL_GCS
    } else { // default old generation
      gc_policy = new MarkSweepPolicy();
    }
    gc_policy->initialize_all();

    Universe::_collectedHeap = new GenCollectedHeap(gc_policy);
  }

  jint status = Universe::heap()->initialize();
  if (status != JNI_OK) {
    return status;
  }

#ifdef _LP64
  if (UseCompressedOops) {
    // Subtract a page because something can get allocated at heap base.
    // This also makes implicit null checking work, because the
    // memory+1 page below heap_base needs to cause a signal.
    // See needs_explicit_null_check.
    // Only set the heap base for compressed oops because it indicates
    // compressed oops for pstack code.
    bool verbose = PrintCompressedOopsMode || (PrintMiscellaneous && Verbose);
    if (verbose) {
      tty->cr();
      tty->print("heap address: " PTR_FORMAT ", size: " SIZE_FORMAT " MB",
                 Universe::heap()->base(), Universe::heap()->reserved_region().byte_size()/M);
    }
    if (((uint64_t)Universe::heap()->reserved_region().end() > OopEncodingHeapMax)) {
      // Can't reserve heap below 32Gb.
      // keep the Universe::narrow_oop_base() set in Universe::reserve_heap()
      Universe::set_narrow_oop_shift(LogMinObjAlignmentInBytes);
      if (verbose) {
        tty->print(", %s: "PTR_FORMAT,
            narrow_oop_mode_to_string(HeapBasedNarrowOop),
            Universe::narrow_oop_base());
      }
    } else {
      Universe::set_narrow_oop_base(0);
      if (verbose) {
        tty->print(", %s", narrow_oop_mode_to_string(ZeroBasedNarrowOop));
      }
#ifdef _WIN64
      if (!Universe::narrow_oop_use_implicit_null_checks()) {
        // Don't need guard page for implicit checks in indexed addressing
        // mode with zero based Compressed Oops.
        Universe::set_narrow_oop_use_implicit_null_checks(true);
      }
#endif //  _WIN64
      if((uint64_t)Universe::heap()->reserved_region().end() > UnscaledOopHeapMax) {
        // Can't reserve heap below 4Gb.
        Universe::set_narrow_oop_shift(LogMinObjAlignmentInBytes);
      } else {
        Universe::set_narrow_oop_shift(0);
        if (verbose) {
          tty->print(", %s", narrow_oop_mode_to_string(UnscaledNarrowOop));
        }
      }
    }

    if (verbose) {
      tty->cr();
      tty->cr();
    }
    Universe::set_narrow_ptrs_base(Universe::narrow_oop_base());
  }
  // Universe::narrow_oop_base() is one page below the heap.
  assert((intptr_t)Universe::narrow_oop_base() <= (intptr_t)(Universe::heap()->base() -
         os::vm_page_size()) ||
         Universe::narrow_oop_base() == NULL, "invalid value");
  assert(Universe::narrow_oop_shift() == LogMinObjAlignmentInBytes ||
         Universe::narrow_oop_shift() == 0, "invalid value");
#endif

  // We will never reach the CATCH below since Exceptions::_throw will cause
  // the VM to exit if an exception is thrown during initialization

  if (UseTLAB) {
    assert(Universe::heap()->supports_tlab_allocation(),
           "Should support thread-local allocation buffers");
    ThreadLocalAllocBuffer::startup_initialization();
  }
  return JNI_OK;
}


// Reserve the Java heap, which is now the same for all GCs.
ReservedSpace Universe::reserve_heap(size_t heap_size, size_t alignment) {
  assert(alignment <= Arguments::conservative_max_heap_alignment(),
      err_msg("actual alignment "SIZE_FORMAT" must be within maximum heap alignment "SIZE_FORMAT,
          alignment, Arguments::conservative_max_heap_alignment()));
  size_t total_reserved = align_size_up(heap_size, alignment);
  assert(!UseCompressedOops || (total_reserved <= (OopEncodingHeapMax - os::vm_page_size())),
      "heap size is too big for compressed oops");

  bool use_large_pages = UseLargePages && is_size_aligned(alignment, os::large_page_size());
  assert(!UseLargePages
      || UseParallelGC
      || use_large_pages, "Wrong alignment to use large pages");

  char* addr = Universe::preferred_heap_base(total_reserved, alignment, Universe::UnscaledNarrowOop);

  ReservedHeapSpace total_rs(total_reserved, alignment, use_large_pages, addr);

  if (UseCompressedOops) {
    if (addr != NULL && !total_rs.is_reserved()) {
      // Failed to reserve at specified address - the requested memory
      // region is taken already, for example, by 'java' launcher.
      // Try again to reserver heap higher.
      addr = Universe::preferred_heap_base(total_reserved, alignment, Universe::ZeroBasedNarrowOop);

      ReservedHeapSpace total_rs0(total_reserved, alignment,
          use_large_pages, addr);

      if (addr != NULL && !total_rs0.is_reserved()) {
        // Failed to reserve at specified address again - give up.
        addr = Universe::preferred_heap_base(total_reserved, alignment, Universe::HeapBasedNarrowOop);
        assert(addr == NULL, "");

        ReservedHeapSpace total_rs1(total_reserved, alignment,
            use_large_pages, addr);
        total_rs = total_rs1;
      } else {
        total_rs = total_rs0;
      }
    }
  }

  if (!total_rs.is_reserved()) {
    vm_exit_during_initialization(err_msg("Could not reserve enough space for " SIZE_FORMAT "KB object heap", total_reserved/K));
    return total_rs;
  }

  if (UseCompressedOops) {
    // Universe::initialize_heap() will reset this to NULL if unscaled
    // or zero-based narrow oops are actually used.
    address base = (address)(total_rs.base() - os::vm_page_size());
    Universe::set_narrow_oop_base(base);
  }
  return total_rs;
}


// It's the caller's responsibility to ensure glitch-freedom
// (if required).
void Universe::update_heap_info_at_gc() {
  _heap_capacity_at_last_gc = heap()->capacity();
  _heap_used_at_last_gc     = heap()->used();
}


const char* Universe::narrow_oop_mode_to_string(Universe::NARROW_OOP_MODE mode) {
  switch (mode) {
    case UnscaledNarrowOop:
      return "32-bits Oops";
    case ZeroBasedNarrowOop:
      return "zero based Compressed Oops";
    case HeapBasedNarrowOop:
      return "Compressed Oops with base";
  }

  ShouldNotReachHere();
  return "";
}


Universe::NARROW_OOP_MODE Universe::narrow_oop_mode() {
  if (narrow_oop_base() != 0) {
    return HeapBasedNarrowOop;
  }

  if (narrow_oop_shift() != 0) {
    return ZeroBasedNarrowOop;
  }

  return UnscaledNarrowOop;
}


void universe2_init() {
  EXCEPTION_MARK;
  Universe::genesis(CATCH);
}


// This function is defined in JVM.cpp
extern void initialize_converter_functions();

bool universe_post_init() {
  assert(!is_init_completed(), "Error: initialization not yet completed!");
  Universe::_fully_initialized = true;
  EXCEPTION_MARK;
  { ResourceMark rm;
    Interpreter::initialize();      // needed for interpreter entry points
    if (!UseSharedSpaces) {
      HandleMark hm(THREAD);
      KlassHandle ok_h(THREAD, SystemDictionary::Object_klass());
      Universe::reinitialize_vtable_of(ok_h, CHECK_false);
      Universe::reinitialize_itables(CHECK_false);
    }
  }

  HandleMark hm(THREAD);
  Klass* k;
  instanceKlassHandle k_h;
    // Setup preallocated empty java.lang.Class array
    Universe::_the_empty_class_klass_array = oopFactory::new_objArray(SystemDictionary::Class_klass(), 0, CHECK_false);

    // Setup preallocated OutOfMemoryError errors
    k = SystemDictionary::resolve_or_fail(vmSymbols::java_lang_OutOfMemoryError(), true, CHECK_false);
    k_h = instanceKlassHandle(THREAD, k);
    Universe::_out_of_memory_error_java_heap = k_h->allocate_instance(CHECK_false);
    Universe::_out_of_memory_error_metaspace = k_h->allocate_instance(CHECK_false);
    Universe::_out_of_memory_error_class_metaspace = k_h->allocate_instance(CHECK_false);
    Universe::_out_of_memory_error_array_size = k_h->allocate_instance(CHECK_false);
    Universe::_out_of_memory_error_gc_overhead_limit =
      k_h->allocate_instance(CHECK_false);

    // Setup preallocated NullPointerException
    // (this is currently used for a cheap & dirty solution in compiler exception handling)
    k = SystemDictionary::resolve_or_fail(vmSymbols::java_lang_NullPointerException(), true, CHECK_false);
    Universe::_null_ptr_exception_instance = InstanceKlass::cast(k)->allocate_instance(CHECK_false);
    // Setup preallocated ArithmeticException
    // (this is currently used for a cheap & dirty solution in compiler exception handling)
    k = SystemDictionary::resolve_or_fail(vmSymbols::java_lang_ArithmeticException(), true, CHECK_false);
    Universe::_arithmetic_exception_instance = InstanceKlass::cast(k)->allocate_instance(CHECK_false);
    // Virtual Machine Error for when we get into a situation we can't resolve
    k = SystemDictionary::resolve_or_fail(
      vmSymbols::java_lang_VirtualMachineError(), true, CHECK_false);
    bool linked = InstanceKlass::cast(k)->link_class_or_fail(CHECK_false);
    if (!linked) {
      tty->print_cr("Unable to link/verify VirtualMachineError class");
      return false; // initialization failed
    }
    Universe::_virtual_machine_error_instance =
      InstanceKlass::cast(k)->allocate_instance(CHECK_false);

    Universe::_vm_exception = InstanceKlass::cast(k)->allocate_instance(CHECK_false);

  if (!DumpSharedSpaces) {
    // These are the only Java fields that are currently set during shared space dumping.
    // We prefer to not handle this generally, so we always reinitialize these detail messages.
    Handle msg = java_lang_String::create_from_str("Java heap space", CHECK_false);
    java_lang_Throwable::set_message(Universe::_out_of_memory_error_java_heap, msg());

    msg = java_lang_String::create_from_str("Metaspace", CHECK_false);
    java_lang_Throwable::set_message(Universe::_out_of_memory_error_metaspace, msg());
    msg = java_lang_String::create_from_str("Compressed class space", CHECK_false);
    java_lang_Throwable::set_message(Universe::_out_of_memory_error_class_metaspace, msg());

    msg = java_lang_String::create_from_str("Requested array size exceeds VM limit", CHECK_false);
    java_lang_Throwable::set_message(Universe::_out_of_memory_error_array_size, msg());

    msg = java_lang_String::create_from_str("GC overhead limit exceeded", CHECK_false);
    java_lang_Throwable::set_message(Universe::_out_of_memory_error_gc_overhead_limit, msg());

    msg = java_lang_String::create_from_str("/ by zero", CHECK_false);
    java_lang_Throwable::set_message(Universe::_arithmetic_exception_instance, msg());

    // Setup the array of errors that have preallocated backtrace
    k = Universe::_out_of_memory_error_java_heap->klass();
    assert(k->name() == vmSymbols::java_lang_OutOfMemoryError(), "should be out of memory error");
    k_h = instanceKlassHandle(THREAD, k);

    int len = (StackTraceInThrowable) ? (int)PreallocatedOutOfMemoryErrorCount : 0;
    Universe::_preallocated_out_of_memory_error_array = oopFactory::new_objArray(k_h(), len, CHECK_false);
    for (int i=0; i<len; i++) {
      oop err = k_h->allocate_instance(CHECK_false);
      Handle err_h = Handle(THREAD, err);
      java_lang_Throwable::allocate_backtrace(err_h, CHECK_false);
      Universe::preallocated_out_of_memory_errors()->obj_at_put(i, err_h());
    }
    Universe::_preallocated_out_of_memory_error_avail_count = (jint)len;
  }


  // Setup static method for registering finalizers
  // The finalizer klass must be linked before looking up the method, in
  // case it needs to get rewritten.
  InstanceKlass::cast(SystemDictionary::Finalizer_klass())->link_class(CHECK_false);
  Method* m = InstanceKlass::cast(SystemDictionary::Finalizer_klass())->find_method(
                                  vmSymbols::register_method_name(),
                                  vmSymbols::register_method_signature());
  if (m == NULL || !m->is_static()) {
    tty->print_cr("Unable to link/verify Finalizer.register method");
    return false; // initialization failed (cannot throw exception yet)
  }
  Universe::_finalizer_register_cache->init(
    SystemDictionary::Finalizer_klass(), m);

  InstanceKlass::cast(SystemDictionary::misc_Unsafe_klass())->link_class(CHECK_false);
  m = InstanceKlass::cast(SystemDictionary::misc_Unsafe_klass())->find_method(
                                  vmSymbols::throwIllegalAccessError_name(),
                                  vmSymbols::void_method_signature());
  if (m != NULL && !m->is_static()) {
    // Note null is okay; this method is used in itables, and if it is null,
    // then AbstractMethodError is thrown instead.
    tty->print_cr("Unable to link/verify Unsafe.throwIllegalAccessError method");
    return false; // initialization failed (cannot throw exception yet)
  }
  Universe::_throw_illegal_access_error = m;

  // Setup method for registering loaded classes in class loader vector
  InstanceKlass::cast(SystemDictionary::ClassLoader_klass())->link_class(CHECK_false);
  m = InstanceKlass::cast(SystemDictionary::ClassLoader_klass())->find_method(vmSymbols::addClass_name(), vmSymbols::class_void_signature());
  if (m == NULL || m->is_static()) {
    tty->print_cr("Unable to link/verify ClassLoader.addClass method");
    return false; // initialization failed (cannot throw exception yet)
  }
  Universe::_loader_addClass_cache->init(
    SystemDictionary::ClassLoader_klass(), m);

  // Setup method for checking protection domain
  InstanceKlass::cast(SystemDictionary::ProtectionDomain_klass())->link_class(CHECK_false);
  m = InstanceKlass::cast(SystemDictionary::ProtectionDomain_klass())->
            find_method(vmSymbols::impliesCreateAccessControlContext_name(),
                        vmSymbols::void_boolean_signature());
  // Allow NULL which should only happen with bootstrapping.
  if (m != NULL) {
    if (m->is_static()) {
      // NoSuchMethodException doesn't actually work because it tries to run the
      // <init> function before java_lang_Class is linked. Print error and exit.
      tty->print_cr("ProtectionDomain.impliesCreateAccessControlContext() has the wrong linkage");
      return false; // initialization failed
    }
    Universe::_pd_implies_cache->init(
      SystemDictionary::ProtectionDomain_klass(), m);;
  }

  // The folowing is initializing converter functions for serialization in
  // JVM.cpp. If we clean up the StrictMath code above we may want to find
  // a better solution for this as well.
  initialize_converter_functions();

  // This needs to be done before the first scavenge/gc, since
  // it's an input to soft ref clearing policy.
  {
    MutexLocker x(Heap_lock);
    Universe::update_heap_info_at_gc();
  }

  // ("weak") refs processing infrastructure initialization
  Universe::heap()->post_initialize();

  // Initialize performance counters for metaspaces
  MetaspaceCounters::initialize_performance_counters();
  CompressedClassSpaceCounters::initialize_performance_counters();

  MemoryService::add_metaspace_memory_pools();

  GC_locker::unlock();  // allow gc after bootstrapping

  MemoryService::set_universe_heap(Universe::_collectedHeap);
  return true;
}


void Universe::compute_base_vtable_size() {
  _base_vtable_size = ClassLoader::compute_Object_vtable();
}


// %%% The Universe::flush_foo methods belong in CodeCache.

// Flushes compiled methods dependent on dependee.
void Universe::flush_dependents_on(instanceKlassHandle dependee) {
  assert_lock_strong(Compile_lock);

  if (CodeCache::number_of_nmethods_with_dependencies() == 0) return;

  // CodeCache can only be updated by a thread_in_VM and they will all be
  // stopped dring the safepoint so CodeCache will be safe to update without
  // holding the CodeCache_lock.

  KlassDepChange changes(dependee);

  // Compute the dependent nmethods
  if (CodeCache::mark_for_deoptimization(changes) > 0) {
    // At least one nmethod has been marked for deoptimization
    VM_Deoptimize op;
    VMThread::execute(&op);
  }
}

// Flushes compiled methods dependent on a particular CallSite
// instance when its target is different than the given MethodHandle.
void Universe::flush_dependents_on(Handle call_site, Handle method_handle) {
  assert_lock_strong(Compile_lock);

  if (CodeCache::number_of_nmethods_with_dependencies() == 0) return;

  // CodeCache can only be updated by a thread_in_VM and they will all be
  // stopped dring the safepoint so CodeCache will be safe to update without
  // holding the CodeCache_lock.

  CallSiteDepChange changes(call_site(), method_handle());

  // Compute the dependent nmethods that have a reference to a
  // CallSite object.  We use InstanceKlass::mark_dependent_nmethod
  // directly instead of CodeCache::mark_for_deoptimization because we
  // want dependents on the call site class only not all classes in
  // the ContextStream.
  int marked = 0;
  {
    MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
    InstanceKlass* call_site_klass = InstanceKlass::cast(call_site->klass());
    marked = call_site_klass->mark_dependent_nmethods(changes);
  }
  if (marked > 0) {
    // At least one nmethod has been marked for deoptimization
    VM_Deoptimize op;
    VMThread::execute(&op);
  }
}

#ifdef HOTSWAP
// Flushes compiled methods dependent on dependee in the evolutionary sense
void Universe::flush_evol_dependents_on(instanceKlassHandle ev_k_h) {
  // --- Compile_lock is not held. However we are at a safepoint.
  assert_locked_or_safepoint(Compile_lock);
  if (CodeCache::number_of_nmethods_with_dependencies() == 0) return;

  // CodeCache can only be updated by a thread_in_VM and they will all be
  // stopped dring the safepoint so CodeCache will be safe to update without
  // holding the CodeCache_lock.

  // Compute the dependent nmethods
  if (CodeCache::mark_for_evol_deoptimization(ev_k_h) > 0) {
    // At least one nmethod has been marked for deoptimization

    // All this already happens inside a VM_Operation, so we'll do all the work here.
    // Stuff copied from VM_Deoptimize and modified slightly.

    // We do not want any GCs to happen while we are in the middle of this VM operation
    ResourceMark rm;
    DeoptimizationMarker dm;

    // Deoptimize all activations depending on marked nmethods
    Deoptimization::deoptimize_dependents();

    // Make the dependent methods not entrant (in VM_Deoptimize they are made zombies)
    CodeCache::make_marked_nmethods_not_entrant();
  }
}
#endif // HOTSWAP


// Flushes compiled methods dependent on dependee
void Universe::flush_dependents_on_method(methodHandle m_h) {
  // --- Compile_lock is not held. However we are at a safepoint.
  assert_locked_or_safepoint(Compile_lock);

  // CodeCache can only be updated by a thread_in_VM and they will all be
  // stopped dring the safepoint so CodeCache will be safe to update without
  // holding the CodeCache_lock.

  // Compute the dependent nmethods
  if (CodeCache::mark_for_deoptimization(m_h()) > 0) {
    // At least one nmethod has been marked for deoptimization

    // All this already happens inside a VM_Operation, so we'll do all the work here.
    // Stuff copied from VM_Deoptimize and modified slightly.

    // We do not want any GCs to happen while we are in the middle of this VM operation
    ResourceMark rm;
    DeoptimizationMarker dm;

    // Deoptimize all activations depending on marked nmethods
    Deoptimization::deoptimize_dependents();

    // Make the dependent methods not entrant (in VM_Deoptimize they are made zombies)
    CodeCache::make_marked_nmethods_not_entrant();
  }
}

void Universe::print() {
  print_on(gclog_or_tty);
}

void Universe::print_on(outputStream* st, bool extended) {
  st->print_cr("Heap");
  if (!extended) {
    heap()->print_on(st);
  } else {
    heap()->print_extended_on(st);
  }
}

void Universe::print_heap_at_SIGBREAK() {
  if (PrintHeapAtSIGBREAK) {
    MutexLocker hl(Heap_lock);
    print_on(tty);
    tty->cr();
    tty->flush();
  }
}

void Universe::print_heap_before_gc(outputStream* st, bool ignore_extended) {
  st->print_cr("{Heap before GC invocations=%u (full %u):",
               heap()->total_collections(),
               heap()->total_full_collections());
  if (!PrintHeapAtGCExtended || ignore_extended) {
    heap()->print_on(st);
  } else {
    heap()->print_extended_on(st);
  }
}

void Universe::print_heap_after_gc(outputStream* st, bool ignore_extended) {
  st->print_cr("Heap after GC invocations=%u (full %u):",
               heap()->total_collections(),
               heap()->total_full_collections());
  if (!PrintHeapAtGCExtended || ignore_extended) {
    heap()->print_on(st);
  } else {
    heap()->print_extended_on(st);
  }
  st->print_cr("}");
}

void Universe::verify(VerifyOption option, const char* prefix, bool silent) {
  // The use of _verify_in_progress is a temporary work around for
  // 6320749.  Don't bother with a creating a class to set and clear
  // it since it is only used in this method and the control flow is
  // straight forward.
  _verify_in_progress = true;

  COMPILER2_PRESENT(
    assert(!DerivedPointerTable::is_active(),
         "DPT should not be active during verification "
         "(of thread stacks below)");
  )

  ResourceMark rm;
  HandleMark hm;  // Handles created during verification can be zapped
  _verify_count++;

  if (!silent) gclog_or_tty->print(prefix);
  if (!silent) gclog_or_tty->print("[Verifying ");
  if (!silent) gclog_or_tty->print("threads ");
  Threads::verify();
  if (!silent) gclog_or_tty->print("heap ");
  heap()->verify(silent, option);
  if (!silent) gclog_or_tty->print("syms ");
  SymbolTable::verify();
  if (!silent) gclog_or_tty->print("strs ");
  StringTable::verify();
  {
    MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
    if (!silent) gclog_or_tty->print("zone ");
    CodeCache::verify();
  }
  if (!silent) gclog_or_tty->print("dict ");
  SystemDictionary::verify();
#ifndef PRODUCT
  if (!silent) gclog_or_tty->print("cldg ");
  ClassLoaderDataGraph::verify();
#endif
  if (!silent) gclog_or_tty->print("metaspace chunks ");
  MetaspaceAux::verify_free_chunks();
  if (!silent) gclog_or_tty->print("hand ");
  JNIHandles::verify();
  if (!silent) gclog_or_tty->print("C-heap ");
  os::check_heap();
  if (!silent) gclog_or_tty->print("code cache ");
  CodeCache::verify_oops();
  if (!silent) gclog_or_tty->print_cr("]");

  _verify_in_progress = false;
}

// Oop verification (see MacroAssembler::verify_oop)

static uintptr_t _verify_oop_data[2]   = {0, (uintptr_t)-1};
static uintptr_t _verify_klass_data[2] = {0, (uintptr_t)-1};


#ifndef PRODUCT

static void calculate_verify_data(uintptr_t verify_data[2],
                                  HeapWord* low_boundary,
                                  HeapWord* high_boundary) {
  assert(low_boundary < high_boundary, "bad interval");

  // decide which low-order bits we require to be clear:
  size_t alignSize = MinObjAlignmentInBytes;
  size_t min_object_size = CollectedHeap::min_fill_size();

  // make an inclusive limit:
  uintptr_t max = (uintptr_t)high_boundary - min_object_size*wordSize;
  uintptr_t min = (uintptr_t)low_boundary;
  assert(min < max, "bad interval");
  uintptr_t diff = max ^ min;

  // throw away enough low-order bits to make the diff vanish
  uintptr_t mask = (uintptr_t)(-1);
  while ((mask & diff) != 0)
    mask <<= 1;
  uintptr_t bits = (min & mask);
  assert(bits == (max & mask), "correct mask");
  // check an intermediate value between min and max, just to make sure:
  assert(bits == ((min + (max-min)/2) & mask), "correct mask");

  // require address alignment, too:
  mask |= (alignSize - 1);

  if (!(verify_data[0] == 0 && verify_data[1] == (uintptr_t)-1)) {
    assert(verify_data[0] == mask && verify_data[1] == bits, "mask stability");
  }
  verify_data[0] = mask;
  verify_data[1] = bits;
}

// Oop verification (see MacroAssembler::verify_oop)

uintptr_t Universe::verify_oop_mask() {
  MemRegion m = heap()->reserved_region();
  calculate_verify_data(_verify_oop_data,
                        m.start(),
                        m.end());
  return _verify_oop_data[0];
}



uintptr_t Universe::verify_oop_bits() {
  verify_oop_mask();
  return _verify_oop_data[1];
}

uintptr_t Universe::verify_mark_mask() {
  return markOopDesc::lock_mask_in_place;
}

uintptr_t Universe::verify_mark_bits() {
  intptr_t mask = verify_mark_mask();
  intptr_t bits = (intptr_t)markOopDesc::prototype();
  assert((bits & ~mask) == 0, "no stray header bits");
  return bits;
}
#endif // PRODUCT


void Universe::compute_verify_oop_data() {
  verify_oop_mask();
  verify_oop_bits();
  verify_mark_mask();
  verify_mark_bits();
}


void LatestMethodCache::init(Klass* k, Method* m) {
  if (!UseSharedSpaces) {
    _klass = k;
  }
#ifndef PRODUCT
  else {
    // sharing initilization should have already set up _klass
    assert(_klass != NULL, "just checking");
  }
#endif

  _method_idnum = m->method_idnum();
  assert(_method_idnum >= 0, "sanity check");
}


Method* LatestMethodCache::get_method() {
  if (klass() == NULL) return NULL;
  InstanceKlass* ik = InstanceKlass::cast(klass());
  Method* m = ik->method_with_idnum(method_idnum());
  assert(m != NULL, "sanity check");
  return m;
}


#ifdef ASSERT
// Release dummy object(s) at bottom of heap
bool Universe::release_fullgc_alot_dummy() {
  MutexLocker ml(FullGCALot_lock);
  if (_fullgc_alot_dummy_array != NULL) {
    if (_fullgc_alot_dummy_next >= _fullgc_alot_dummy_array->length()) {
      // No more dummies to release, release entire array instead
      _fullgc_alot_dummy_array = NULL;
      return false;
    }
    if (!UseConcMarkSweepGC) {
      // Release dummy at bottom of old generation
      _fullgc_alot_dummy_array->obj_at_put(_fullgc_alot_dummy_next++, NULL);
    }
    // Release dummy at bottom of permanent generation
    _fullgc_alot_dummy_array->obj_at_put(_fullgc_alot_dummy_next++, NULL);
  }
  return true;
}

#endif // ASSERT

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