Subversion Repositories openrisc

/***

 * ASM: a very small and fast Java bytecode manipulation framework

 * Copyright (c) 2000-2005 INRIA, France Telecom

 * All rights reserved.

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions

 * are met:

 * 1. Redistributions of source code must retain the above copyright

 *    notice, this list of conditions and the following disclaimer.

 * 2. Redistributions in binary form must reproduce the above copyright

 *    notice, this list of conditions and the following disclaimer in the

 *    documentation and/or other materials provided with the distribution.

 * 3. Neither the name of the copyright holders nor the names of its

 *    contributors may be used to endorse or promote products derived from

 *    this software without specific prior written permission.

 *

 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"

 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE

 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE

 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE

 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR

 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF

 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS

 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN

 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)

 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF

 * THE POSSIBILITY OF SUCH DAMAGE.

 */

package org.objectweb.asm.optimizer;

import org.objectweb.asm.ClassWriter;

/**

 * A constant pool item.

 *

 * @author Eric Bruneton

 */

class Constant {

    /**

     * Type of this constant pool item. A single class is used to represent all

     * constant pool item types, in order to minimize the bytecode size of this

     * package. The value of this field is I, J, F, D, S, s, C, T, G, M, or N

     * (for Constant Integer, Long, Float, Double, STR, UTF8, Class, NameType,

     * Fieldref, Methodref, or InterfaceMethodref constant pool items

     * respectively).

     */

    char type;

    /**

     * Value of this item, for an integer item.

     */

    int intVal;

    /**

     * Value of this item, for a long item.

     */

    long longVal;

    /**

     * Value of this item, for a float item.

     */

    float floatVal;

    /**

     * Value of this item, for a double item.

     */

    double doubleVal;

    /**

     * First part of the value of this item, for items that do not hold a

     * primitive value.

     */

    String strVal1;

    /**

     * Second part of the value of this item, for items that do not hold a

     * primitive value.

     */

    String strVal2;

    /**

     * Third part of the value of this item, for items that do not hold a

     * primitive value.

     */

    String strVal3;

    /**

     * The hash code value of this constant pool item.

     */

    int hashCode;

    public Constant() {

    }

    public Constant(final Constant i) {

        type = i.type;

        intVal = i.intVal;

        longVal = i.longVal;

        floatVal = i.floatVal;

        doubleVal = i.doubleVal;

        strVal1 = i.strVal1;

        strVal2 = i.strVal2;

        strVal3 = i.strVal3;

        hashCode = i.hashCode;

    }

    /**

     * Sets this item to an integer item.

     *

     * @param intVal the value of this item.

     */

    void set(final int intVal) {

        this.type = 'I';

        this.intVal = intVal;

        this.hashCode = 0x7FFFFFFF & (type + intVal);

    }

    /**

     * Sets this item to a long item.

     *

     * @param longVal the value of this item.

     */

    void set(final long longVal) {

        this.type = 'J';

        this.longVal = longVal;

        this.hashCode = 0x7FFFFFFF & (type + (int) longVal);

    }

    /**

     * Sets this item to a float item.

     *

     * @param floatVal the value of this item.

     */

    void set(final float floatVal) {

        this.type = 'F';

        this.floatVal = floatVal;

        this.hashCode = 0x7FFFFFFF & (type + (int) floatVal);

    }

    /**

     * Sets this item to a double item.

     *

     * @param doubleVal the value of this item.

     */

    void set(final double doubleVal) {

        this.type = 'D';

        this.doubleVal = doubleVal;

        this.hashCode = 0x7FFFFFFF & (type + (int) doubleVal);

    }

    /**

     * Sets this item to an item that do not hold a primitive value.

     *

     * @param type the type of this item.

     * @param strVal1 first part of the value of this item.

     * @param strVal2 second part of the value of this item.

     * @param strVal3 third part of the value of this item.

     */

    void set(

        final char type,

        final String strVal1,

        final String strVal2,

        final String strVal3)

    {

        this.type = type;

        this.strVal1 = strVal1;

        this.strVal2 = strVal2;

        this.strVal3 = strVal3;

        switch (type) {

            case 's':

            case 'S':

            case 'C':

                hashCode = 0x7FFFFFFF & (type + strVal1.hashCode());

                return;

            case 'T':

                hashCode = 0x7FFFFFFF & (type + strVal1.hashCode()

                        * strVal2.hashCode());

                return;

            // case 'G':

            // case 'M':

            // case 'N':

            default:

                hashCode = 0x7FFFFFFF & (type + strVal1.hashCode()

                        * strVal2.hashCode() * strVal3.hashCode());

        }

    }

    void write(final ClassWriter cw) {

        switch (type) {

            case 'I':

                cw.newConst(new Integer(intVal));

                break;

            case 'J':

                cw.newConst(new Long(longVal));

                break;

            case 'F':

                cw.newConst(new Float(floatVal));

                break;

            case 'D':

                cw.newConst(new Double(doubleVal));

                break;

            case 'S':

                cw.newConst(strVal1);

                break;

            case 's':

                cw.newUTF8(strVal1);

                break;

            case 'C':

                cw.newClass(strVal1);

                break;

            case 'T':

                cw.newNameType(strVal1, strVal2);

                break;

            case 'G':

                cw.newField(strVal1, strVal2, strVal3);

                break;

            case 'M':

                cw.newMethod(strVal1, strVal2, strVal3, false);

                break;

            case 'N':

                cw.newMethod(strVal1, strVal2, strVal3, true);

                break;

        }

    }

    public boolean equals(final Object o) {

        if (!(o instanceof Constant)) {

            return false;

        }

        Constant c = (Constant) o;

        if (c.type == type) {

            switch (type) {

                case 'I':

                    return c.intVal == intVal;

                case 'J':

                    return c.longVal == longVal;

                case 'F':

                    return c.floatVal == floatVal;

                case 'D':

                    return c.doubleVal == doubleVal;

                case 's':

                case 'S':

                case 'C':

                    return c.strVal1.equals(strVal1);

                case 'T':

                    return c.strVal1.equals(strVal1)

                            && c.strVal2.equals(strVal2);

                // case 'G':

                // case 'M':

                // case 'N':

                default:

                    return c.strVal1.equals(strVal1)

                            && c.strVal2.equals(strVal2)

                            && c.strVal3.equals(strVal3);

            }

        }

        return false;

    }

    public int hashCode() {

        return hashCode;

    }

}