/*

 * Copyright 1999-2008 Sun Microsystems, Inc.  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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,

 * CA 95054 USA or visit www.sun.com if you need additional information or

 * have any questions.

 *

 */

#include "incls/_precompiled.incl"

#include "incls/_ciObjectFactory.cpp.incl"

// ciObjectFactory

//

// This class handles requests for the creation of new instances

// of ciObject and its subclasses.  It contains a caching mechanism

// which ensures that for each oop, at most one ciObject is created.

// This invariant allows more efficient implementation of ciObject.

//

// Implementation note: the oop->ciObject mapping is represented as

// a table stored in an array.  Even though objects are moved

// by the garbage collector, the compactor preserves their relative

// order; address comparison of oops (in perm space) is safe so long

// as we prohibit GC during our comparisons.  We currently use binary

// search to find the oop in the table, and inserting a new oop

// into the table may be costly.  If this cost ends up being

// problematic the underlying data structure can be switched to some

// sort of balanced binary tree.

GrowableArray<ciObject*>* ciObjectFactory::_shared_ci_objects = NULL;

ciSymbol*                 ciObjectFactory::_shared_ci_symbols[vmSymbols::SID_LIMIT];

int                       ciObjectFactory::_shared_ident_limit = 0;

volatile bool             ciObjectFactory::_initialized = false;

// ------------------------------------------------------------------

// ciObjectFactory::ciObjectFactory

ciObjectFactory::ciObjectFactory(Arena* arena,

                                 int expected_size) {

  for (int i = 0; i < NON_PERM_BUCKETS; i++) {

    _non_perm_bucket[i] = NULL;

  }

  _non_perm_count = 0;

  _next_ident = _shared_ident_limit;

  _arena = arena;

  _ci_objects = new (arena) GrowableArray<ciObject*>(arena, expected_size, 0, NULL);

  // If the shared ci objects exist append them to this factory's objects

  if (_shared_ci_objects != NULL) {

    _ci_objects->appendAll(_shared_ci_objects);

  }

  _unloaded_methods = new (arena) GrowableArray<ciMethod*>(arena, 4, 0, NULL);

  _unloaded_klasses = new (arena) GrowableArray<ciKlass*>(arena, 8, 0, NULL);

  _return_addresses =

    new (arena) GrowableArray<ciReturnAddress*>(arena, 8, 0, NULL);

}

// ------------------------------------------------------------------

// ciObjectFactory::ciObjectFactory

void ciObjectFactory::initialize() {

  ASSERT_IN_VM;

  JavaThread* thread = JavaThread::current();

  HandleMark  handle_mark(thread);

  // This Arena is long lived and exists in the resource mark of the

  // compiler thread that initializes the initial ciObjectFactory which

  // creates the shared ciObjects that all later ciObjectFactories use.

  Arena* arena = new Arena();

  ciEnv initial(arena);

  ciEnv* env = ciEnv::current();

  env->_factory->init_shared_objects();

  _initialized = true;

}

void ciObjectFactory::init_shared_objects() {

  _next_ident = 1;  // start numbering CI objects at 1

  {

    // Create the shared symbols, but not in _shared_ci_objects.

    int i;

    for (i = vmSymbols::FIRST_SID; i < vmSymbols::SID_LIMIT; i++) {

      symbolHandle sym_handle = vmSymbolHandles::symbol_handle_at((vmSymbols::SID) i);

      assert(vmSymbols::find_sid(sym_handle()) == i, "1-1 mapping");

      ciSymbol* sym = new (_arena) ciSymbol(sym_handle);

      init_ident_of(sym);

      _shared_ci_symbols[i] = sym;

    }

#ifdef ASSERT

    for (i = vmSymbols::FIRST_SID; i < vmSymbols::SID_LIMIT; i++) {

      symbolHandle sym_handle = vmSymbolHandles::symbol_handle_at((vmSymbols::SID) i);

      ciSymbol* sym = vm_symbol_at((vmSymbols::SID) i);

      assert(sym->get_oop() == sym_handle(), "oop must match");

    }

    assert(ciSymbol::void_class_signature()->get_oop() == vmSymbols::void_class_signature(), "spot check");

#endif

  }

  _ci_objects = new (_arena) GrowableArray<ciObject*>(_arena, 64, 0, NULL);

  for (int i = T_BOOLEAN; i <= T_CONFLICT; i++) {

    BasicType t = (BasicType)i;

    if (type2name(t) != NULL && t != T_OBJECT && t != T_ARRAY && t != T_NARROWOOP) {

      ciType::_basic_types[t] = new (_arena) ciType(t);

      init_ident_of(ciType::_basic_types[t]);

    }

  }

  ciEnv::_null_object_instance = new (_arena) ciNullObject();

  init_ident_of(ciEnv::_null_object_instance);

  ciEnv::_method_klass_instance =

    get(Universe::methodKlassObj())->as_method_klass();

  ciEnv::_symbol_klass_instance =

    get(Universe::symbolKlassObj())->as_symbol_klass();

  ciEnv::_klass_klass_instance =

    get(Universe::klassKlassObj())->as_klass_klass();

  ciEnv::_instance_klass_klass_instance =

    get(Universe::instanceKlassKlassObj())

      ->as_instance_klass_klass();

  ciEnv::_type_array_klass_klass_instance =

    get(Universe::typeArrayKlassKlassObj())

      ->as_type_array_klass_klass();

  ciEnv::_obj_array_klass_klass_instance =

    get(Universe::objArrayKlassKlassObj())

      ->as_obj_array_klass_klass();

  ciEnv::_ArrayStoreException =

    get(SystemDictionary::ArrayStoreException_klass())

      ->as_instance_klass();

  ciEnv::_Class =

    get(SystemDictionary::class_klass())

      ->as_instance_klass();

  ciEnv::_ClassCastException =

    get(SystemDictionary::ClassCastException_klass())

      ->as_instance_klass();

  ciEnv::_Object =

    get(SystemDictionary::object_klass())

      ->as_instance_klass();

  ciEnv::_Throwable =

    get(SystemDictionary::throwable_klass())

      ->as_instance_klass();

  ciEnv::_Thread =

    get(SystemDictionary::thread_klass())

      ->as_instance_klass();

  ciEnv::_OutOfMemoryError =

    get(SystemDictionary::OutOfMemoryError_klass())

      ->as_instance_klass();

  ciEnv::_String =

    get(SystemDictionary::string_klass())

      ->as_instance_klass();

  for (int len = -1; len != _ci_objects->length(); ) {

    len = _ci_objects->length();

    for (int i2 = 0; i2 < len; i2++) {

      ciObject* obj = _ci_objects->at(i2);

      if (obj->is_loaded() && obj->is_instance_klass()) {

        obj->as_instance_klass()->compute_nonstatic_fields();

      }

    }

  }

  ciEnv::_unloaded_cisymbol = (ciSymbol*) ciObjectFactory::get(vmSymbols::dummy_symbol_oop());

  // Create dummy instanceKlass and objArrayKlass object and assign them idents

  ciEnv::_unloaded_ciinstance_klass = new (_arena) ciInstanceKlass(ciEnv::_unloaded_cisymbol, NULL, NULL);

  init_ident_of(ciEnv::_unloaded_ciinstance_klass);

  ciEnv::_unloaded_ciobjarrayklass = new (_arena) ciObjArrayKlass(ciEnv::_unloaded_cisymbol, ciEnv::_unloaded_ciinstance_klass, 1);

  init_ident_of(ciEnv::_unloaded_ciobjarrayklass);

  assert(ciEnv::_unloaded_ciobjarrayklass->is_obj_array_klass(), "just checking");

  get(Universe::boolArrayKlassObj());

  get(Universe::charArrayKlassObj());

  get(Universe::singleArrayKlassObj());

  get(Universe::doubleArrayKlassObj());

  get(Universe::byteArrayKlassObj());

  get(Universe::shortArrayKlassObj());

  get(Universe::intArrayKlassObj());

  get(Universe::longArrayKlassObj());

  assert(_non_perm_count == 0, "no shared non-perm objects");

  // The shared_ident_limit is the first ident number that will

  // be used for non-shared objects.  That is, numbers less than

  // this limit are permanently assigned to shared CI objects,

  // while the higher numbers are recycled afresh by each new ciEnv.

  _shared_ident_limit = _next_ident;

  _shared_ci_objects = _ci_objects;

}

// ------------------------------------------------------------------

// ciObjectFactory::get

//

// Get the ciObject corresponding to some oop.  If the ciObject has

// already been created, it is returned.  Otherwise, a new ciObject

// is created.

ciObject* ciObjectFactory::get(oop key) {

  ASSERT_IN_VM;

#ifdef ASSERT

  oop last = NULL;

  for (int j = 0; j< _ci_objects->length(); j++) {

    oop o = _ci_objects->at(j)->get_oop();

    assert(last < o, "out of order");

    last = o;

  }

#endif // ASSERT

  int len = _ci_objects->length();

  int index = find(key, _ci_objects);

#ifdef ASSERT

  for (int i=0; i<_ci_objects->length(); i++) {

    if (_ci_objects->at(i)->get_oop() == key) {

      assert(index == i, " bad lookup");

    }

  }

#endif

  if (!is_found_at(index, key, _ci_objects)) {

    // Check in the non-perm area before putting it in the list.

    NonPermObject* &bucket = find_non_perm(key);

    if (bucket != NULL) {

      return bucket->object();

    }

    // Check in the shared symbol area before putting it in the list.

    if (key->is_symbol()) {

      vmSymbols::SID sid = vmSymbols::find_sid((symbolOop)key);

      if (sid != vmSymbols::NO_SID) {

        // do not pollute the main cache with it

        return vm_symbol_at(sid);

      }

    }

    // The ciObject does not yet exist.  Create it and insert it

    // into the cache.

    Handle keyHandle(key);

    ciObject* new_object = create_new_object(keyHandle());

    assert(keyHandle() == new_object->get_oop(), "must be properly recorded");

    init_ident_of(new_object);

    if (!keyHandle->is_perm()) {

      // Not a perm-space object.

      insert_non_perm(bucket, keyHandle(), new_object);

      return new_object;

    }

    new_object->set_perm();

    if (len != _ci_objects->length()) {

      // creating the new object has recursively entered new objects

      // into the table.  We need to recompute our index.

      index = find(keyHandle(), _ci_objects);

    }

    assert(!is_found_at(index, keyHandle(), _ci_objects), "no double insert");

    insert(index, new_object, _ci_objects);

    return new_object;

  }

  return _ci_objects->at(index);

}

// ------------------------------------------------------------------

// ciObjectFactory::create_new_object

//

// Create a new ciObject from an oop.

//

// Implementation note: this functionality could be virtual behavior

// of the oop itself.  For now, we explicitly marshal the object.

ciObject* ciObjectFactory::create_new_object(oop o) {

  EXCEPTION_CONTEXT;

  if (o->is_symbol()) {

    symbolHandle h_o(THREAD, (symbolOop)o);

    return new (arena()) ciSymbol(h_o);

  } else if (o->is_klass()) {

    KlassHandle h_k(THREAD, (klassOop)o);

    Klass* k = ((klassOop)o)->klass_part();

    if (k->oop_is_instance()) {

      return new (arena()) ciInstanceKlass(h_k);

    } else if (k->oop_is_objArray()) {

      return new (arena()) ciObjArrayKlass(h_k);

    } else if (k->oop_is_typeArray()) {

      return new (arena()) ciTypeArrayKlass(h_k);

    } else if (k->oop_is_method()) {

      return new (arena()) ciMethodKlass(h_k);

    } else if (k->oop_is_symbol()) {

      return new (arena()) ciSymbolKlass(h_k);

    } else if (k->oop_is_klass()) {

      if (k->oop_is_objArrayKlass()) {

        return new (arena()) ciObjArrayKlassKlass(h_k);

      } else if (k->oop_is_typeArrayKlass()) {

        return new (arena()) ciTypeArrayKlassKlass(h_k);

      } else if (k->oop_is_instanceKlass()) {

        return new (arena()) ciInstanceKlassKlass(h_k);

      } else {

        assert(o == Universe::klassKlassObj(), "bad klassKlass");

        return new (arena()) ciKlassKlass(h_k);

      }

    }

  } else if (o->is_method()) {

    methodHandle h_m(THREAD, (methodOop)o);

    return new (arena()) ciMethod(h_m);

  } else if (o->is_methodData()) {

    methodDataHandle h_md(THREAD, (methodDataOop)o);

    return new (arena()) ciMethodData(h_md);

  } else if (o->is_instance()) {

    instanceHandle h_i(THREAD, (instanceOop)o);

    return new (arena()) ciInstance(h_i);

  } else if (o->is_objArray()) {

    objArrayHandle h_oa(THREAD, (objArrayOop)o);

    return new (arena()) ciObjArray(h_oa);

  } else if (o->is_typeArray()) {

    typeArrayHandle h_ta(THREAD, (typeArrayOop)o);

    return new (arena()) ciTypeArray(h_ta);

  }

  // The oop is of some type not supported by the compiler interface.

  ShouldNotReachHere();

  return NULL;

}

//------------------------------------------------------------------

// ciObjectFactory::get_unloaded_method

//

// Get the ciMethod representing an unloaded/unfound method.

//

// Implementation note: unloaded methods are currently stored in

// an unordered array, requiring a linear-time lookup for each

// unloaded method.  This may need to change.

ciMethod* ciObjectFactory::get_unloaded_method(ciInstanceKlass* holder,

                                               ciSymbol*        name,

                                               ciSymbol*        signature) {

  for (int i=0; i<_unloaded_methods->length(); i++) {

    ciMethod* entry = _unloaded_methods->at(i);

    if (entry->holder()->equals(holder) &&

        entry->name()->equals(name) &&

        entry->signature()->as_symbol()->equals(signature)) {

      // We've found a match.

      return entry;

    }

  }

  // This is a new unloaded method.  Create it and stick it in

  // the cache.

  ciMethod* new_method = new (arena()) ciMethod(holder, name, signature);

  init_ident_of(new_method);

  _unloaded_methods->append(new_method);

  return new_method;

}

//------------------------------------------------------------------

// ciObjectFactory::get_unloaded_klass

//

// Get a ciKlass representing an unloaded klass.

//

// Implementation note: unloaded klasses are currently stored in

// an unordered array, requiring a linear-time lookup for each

// unloaded klass.  This may need to change.

ciKlass* ciObjectFactory::get_unloaded_klass(ciKlass* accessing_klass,

                                             ciSymbol* name,

                                             bool create_if_not_found) {

  EXCEPTION_CONTEXT;

  oop loader = NULL;

  oop domain = NULL;

  if (accessing_klass != NULL) {

    loader = accessing_klass->loader();

    domain = accessing_klass->protection_domain();

  }

  for (int i=0; i<_unloaded_klasses->length(); i++) {

    ciKlass* entry = _unloaded_klasses->at(i);

    if (entry->name()->equals(name) &&

        entry->loader() == loader &&

        entry->protection_domain() == domain) {

      // We've found a match.

      return entry;

    }

  }

  if (!create_if_not_found)

    return NULL;

  // This is a new unloaded klass.  Create it and stick it in

  // the cache.

  ciKlass* new_klass = NULL;

  // Two cases: this is an unloaded objArrayKlass or an

  // unloaded instanceKlass.  Deal with both.

  if (name->byte_at(0) == '[') {

    // Decompose the name.'

    jint dimension = 0;

    symbolOop element_name = NULL;

    BasicType element_type= FieldType::get_array_info(name->get_symbolOop(),

                                                      &dimension,

                                                      &element_name,

                                                      THREAD);

    if (HAS_PENDING_EXCEPTION) {

      CLEAR_PENDING_EXCEPTION;

      CURRENT_THREAD_ENV->record_out_of_memory_failure();

      return ciEnv::_unloaded_ciobjarrayklass;

    }

    assert(element_type != T_ARRAY, "unsuccessful decomposition");

    ciKlass* element_klass = NULL;

    if (element_type == T_OBJECT) {

      ciEnv *env = CURRENT_THREAD_ENV;

      ciSymbol* ci_name = env->get_object(element_name)->as_symbol();

      element_klass =

        env->get_klass_by_name(accessing_klass, ci_name, false)->as_instance_klass();

    } else {

      assert(dimension > 1, "one dimensional type arrays are always loaded.");

      // The type array itself takes care of one of the dimensions.

      dimension--;

      // The element klass is a typeArrayKlass.

      element_klass = ciTypeArrayKlass::make(element_type);

    }

    new_klass = new (arena()) ciObjArrayKlass(name, element_klass, dimension);

  } else {

    jobject loader_handle = NULL;

    jobject domain_handle = NULL;

    if (accessing_klass != NULL) {

      loader_handle = accessing_klass->loader_handle();

      domain_handle = accessing_klass->protection_domain_handle();

    }

    new_klass = new (arena()) ciInstanceKlass(name, loader_handle, domain_handle);

  }

  init_ident_of(new_klass);

  _unloaded_klasses->append(new_klass);

  return new_klass;

}

//------------------------------------------------------------------

// ciObjectFactory::get_empty_methodData

//

// Get the ciMethodData representing the methodData for a method with

// none.

ciMethodData* ciObjectFactory::get_empty_methodData() {

  ciMethodData* new_methodData = new (arena()) ciMethodData();

  init_ident_of(new_methodData);

  return new_methodData;

}

//------------------------------------------------------------------

// ciObjectFactory::get_return_address

//

// Get a ciReturnAddress for a specified bci.

ciReturnAddress* ciObjectFactory::get_return_address(int bci) {

  for (int i=0; i<_return_addresses->length(); i++) {

    ciReturnAddress* entry = _return_addresses->at(i);

    if (entry->bci() == bci) {

      // We've found a match.

      return entry;

    }

  }

  ciReturnAddress* new_ret_addr = new (arena()) ciReturnAddress(bci);

  init_ident_of(new_ret_addr);

  _return_addresses->append(new_ret_addr);

  return new_ret_addr;

}

// ------------------------------------------------------------------

// ciObjectFactory::init_ident_of

void ciObjectFactory::init_ident_of(ciObject* obj) {

  obj->set_ident(_next_ident++);

}

// ------------------------------------------------------------------

// ciObjectFactory::find

//

// Use binary search to find the position of this oop in the cache.

// If there is no entry in the cache corresponding to this oop, return

// the position at which the oop should be inserted.

int ciObjectFactory::find(oop key, GrowableArray<ciObject*>* objects) {

  int min = 0;

  int max = objects->length()-1;

  // print_contents();

  while (max >= min) {

    int mid = (max + min) / 2;

    oop value = objects->at(mid)->get_oop();

    if (value < key) {

      min = mid + 1;

    } else if (value > key) {

      max = mid - 1;

    } else {

      return mid;

    }

  }

  return min;

}

// ------------------------------------------------------------------

// ciObjectFactory::is_found_at

//

// Verify that the binary seach found the given key.

bool ciObjectFactory::is_found_at(int index, oop key, GrowableArray<ciObject*>* objects) {

  return (index < objects->length() &&

          objects->at(index)->get_oop() == key);

}

// ------------------------------------------------------------------

// ciObjectFactory::insert

//

// Insert a ciObject into the table at some index.