/*

 * Copyright (c) 1999, 2010, 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 "ci/ciKlass.hpp"

#include "ci/ciSymbol.hpp"

#include "ci/ciUtilities.hpp"

#include "oops/oop.inline.hpp"

// ciKlass

//

// This class represents a klassOop in the HotSpot virtual

// machine.

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

// ciKlass::ciKlass

ciKlass::ciKlass(KlassHandle h_k) : ciType(h_k) {

  assert(get_oop()->is_klass(), "wrong type");

  Klass* k = get_Klass();

  _layout_helper = k->layout_helper();

  assert(klass_name != NULL, "wrong ciKlass constructor");

}

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

// ciKlass::ciKlass

//

// Nameless klass variant.

ciKlass::ciKlass(KlassHandle h_k, ciSymbol* name) : ciType(h_k) {

  assert(get_oop()->is_klass(), "wrong type");

  _name = name;

  _layout_helper = Klass::_lh_neutral_value;

}

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

// ciKlass::ciKlass

//

// Unloaded klass variant.

ciKlass::ciKlass(ciSymbol* name, ciKlass* klass) : ciType(klass) {

  _name = name;

  _layout_helper = Klass::_lh_neutral_value;

}

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

// ciKlass::is_subtype_of

bool ciKlass::is_subtype_of(ciKlass* that) {

  assert(is_loaded() && that->is_loaded(), "must be loaded");

  assert(is_java_klass() && that->is_java_klass(), "must be java klasses");

  // Check to see if the klasses are identical.

  if (this == that) {

    return true;

  }

  VM_ENTRY_MARK;

  Klass* this_klass = get_Klass();

  klassOop that_klass = that->get_klassOop();

  bool result = this_klass->is_subtype_of(that_klass);

  return result;

}

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

// ciKlass::is_subclass_of

bool ciKlass::is_subclass_of(ciKlass* that) {

  assert(is_loaded() && that->is_loaded(), "must be loaded");

  assert(is_java_klass() && that->is_java_klass(), "must be java klasses");

  // Check to see if the klasses are identical.

  VM_ENTRY_MARK;

  Klass* this_klass = get_Klass();

  klassOop that_klass = that->get_klassOop();

  bool result = this_klass->is_subclass_of(that_klass);

  return result;

}

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

// ciKlass::super_depth

juint ciKlass::super_depth() {

  assert(is_loaded(), "must be loaded");

  assert(is_java_klass(), "must be java klasses");

  VM_ENTRY_MARK;

  Klass* this_klass = get_Klass();

  return this_klass->super_depth();

}

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

// ciKlass::super_check_offset

juint ciKlass::super_check_offset() {

  assert(is_loaded(), "must be loaded");

  assert(is_java_klass(), "must be java klasses");

  VM_ENTRY_MARK;

  Klass* this_klass = get_Klass();

  return this_klass->super_check_offset();

}

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

// ciKlass::super_of_depth

ciKlass* ciKlass::super_of_depth(juint i) {

  assert(is_loaded(), "must be loaded");

  assert(is_java_klass(), "must be java klasses");

  VM_ENTRY_MARK;

  Klass* this_klass = get_Klass();

  klassOop super = this_klass->primary_super_of_depth(i);

  return (super != NULL) ? CURRENT_THREAD_ENV->get_object(super)->as_klass() : NULL;

}

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

// ciKlass::can_be_primary_super

bool ciKlass::can_be_primary_super() {

  assert(is_loaded(), "must be loaded");

  assert(is_java_klass(), "must be java klasses");

  VM_ENTRY_MARK;

  Klass* this_klass = get_Klass();

  return this_klass->can_be_primary_super();

}

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

// ciKlass::least_common_ancestor

//

// Get the shared parent of two klasses.

//

// Implementation note: this method currently goes "over the wall"

// and does all of the work on the VM side.  It could be rewritten

// to use the super() method and do all of the work (aside from the

// lazy computation of super()) in native mode.  This may be

// worthwhile if the compiler is repeatedly requesting the same lca

// computation or possibly if most of the superklasses have already

// been created as ciObjects anyway.  Something to think about...

ciKlass*

ciKlass::least_common_ancestor(ciKlass* that) {

  assert(is_loaded() && that->is_loaded(), "must be loaded");

  assert(is_java_klass() && that->is_java_klass(), "must be java klasses");

  // Check to see if the klasses are identical.

  if (this == that) {

    return this;

  }

  VM_ENTRY_MARK;

  Klass* this_klass = get_Klass();

  Klass* that_klass = that->get_Klass();

  Klass* lca        = this_klass->LCA(that_klass);

  // Many times the LCA will be either this_klass or that_klass.

  // Treat these as special cases.

  if (lca == that_klass) {

    return that;

  }

  if (this_klass == lca) {

    return this;

  }

  // Create the ciInstanceKlass for the lca.

  ciKlass* result =

    CURRENT_THREAD_ENV->get_object(lca->as_klassOop())->as_klass();

  return result;

}

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

// ciKlass::find_klass

//

// Find a klass using this klass's class loader.

ciKlass* ciKlass::find_klass(ciSymbol* klass_name) {

  assert(is_loaded(), "cannot find_klass through an unloaded klass");

  return CURRENT_ENV->get_klass_by_name(this,

                                        klass_name, false);

}

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

// ciKlass::java_mirror

//

// Get the instance of java.lang.Class corresponding to this klass.

// If it is an unloaded instance or array klass, return an unloaded

// mirror object of type Class.

ciInstance* ciKlass::java_mirror() {

  GUARDED_VM_ENTRY(

    if (!is_loaded())

      return ciEnv::current()->get_unloaded_klass_mirror(this);

    oop java_mirror = get_Klass()->java_mirror();

    return CURRENT_ENV->get_object(java_mirror)->as_instance();

  )

}

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

// ciKlass::modifier_flags

jint ciKlass::modifier_flags() {

  assert(is_loaded(), "not loaded");

  GUARDED_VM_ENTRY(

    return get_Klass()->modifier_flags();

  )

}

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

// ciKlass::access_flags

jint ciKlass::access_flags() {

  assert(is_loaded(), "not loaded");

  GUARDED_VM_ENTRY(

    return get_Klass()->access_flags().as_int();

  )

}

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

// ciKlass::print_impl

//

// Implementation of the print method

void ciKlass::print_impl(outputStream* st) {

  st->print(" name=");

  print_name_on(st);

}

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

// ciKlass::print_name

//

// Print the name of this klass

void ciKlass::print_name_on(outputStream* st) {

  name()->print_symbol_on(st);

}