/*

 * Copyright (c) 1999, 2019, 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.

 *

 */

#ifndef SHARE_CI_CICONSTANT_HPP

#define SHARE_CI_CICONSTANT_HPP

#include "ci/ciClassList.hpp"

#include "ci/ciNullObject.hpp"

// ciConstant

//

// This class represents a constant value.

class ciConstant {

  friend class VMStructs;

private:

  friend class ciEnv;

  friend class ciField;

  BasicType _type;

  union {

    jint      _int;

    jlong     _long;

    jfloat    _float;

    jdouble   _double;

    ciObject* _object;

  } _value;

public:

  ciConstant() {

    _type = T_ILLEGAL; _value._long = -1;

  }

  ciConstant(BasicType type, jint value) {

    assert(type != T_LONG && type != T_DOUBLE && type != T_FLOAT,

           "using the wrong ciConstant constructor");

    _type = type; _value._int = value;

  }

  ciConstant(jlong value) {

    _type = T_LONG; _value._long = value;

  }

  ciConstant(jfloat value) {

    _type = T_FLOAT; _value._float = value;

  }

  ciConstant(jdouble value) {

    _type = T_DOUBLE; _value._double = value;

  }

  ciConstant(BasicType type, ciObject* p) {

    _type = type; _value._object = p;

  }

  BasicType basic_type() const { return _type; }

  jboolean  as_boolean() {

    assert(basic_type() == T_BOOLEAN, "wrong type");

    return (jboolean)_value._int;

  }

  jchar     as_char() {

    assert(basic_type() == T_CHAR, "wrong type");

    return (jchar)_value._int;

  }

  jbyte     as_byte() {

    assert(basic_type() == T_BYTE, "wrong type");

    return (jbyte)_value._int;

  }

  jshort    as_short() {

    assert(basic_type() == T_SHORT, "wrong type");

    return (jshort)_value._int;

  }

  jint      as_int() {

    assert(basic_type() == T_BOOLEAN || basic_type() == T_CHAR  ||

           basic_type() == T_BYTE    || basic_type() == T_SHORT ||

           basic_type() == T_INT, "wrong type");

    return _value._int;

  }

  jlong     as_long() {

    assert(basic_type() == T_LONG, "wrong type");

    return _value._long;

  }

  jfloat    as_float() {

    assert(basic_type() == T_FLOAT, "wrong type");

    return _value._float;

  }

  jdouble   as_double() {

    assert(basic_type() == T_DOUBLE, "wrong type");

    return _value._double;

  }

  ciObject* as_object() const {

    return _value._object;

  }

  bool      is_null_or_zero() const {

    if (!is_java_primitive(basic_type())) {

      return as_object()->is_null_object();

    } else if (type2size[basic_type()] == 1) {

      // treat float bits as int, to avoid comparison with -0 and NaN

      return (_value._int == 0);

    } else if (type2size[basic_type()] == 2) {

      // treat double bits as long, to avoid comparison with -0 and NaN

      return (_value._long == 0);

    } else {

      return false;

    }

  }

  bool is_valid() const {

    return basic_type() != T_ILLEGAL;

  }

  // Debugging output

  void print();

};

#endif // SHARE_CI_CICONSTANT_HPP