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RoboVM fork of Soot - A Java optimization framework
There is a newer version: 2.5.0-9
/* Soot - a J*va Optimization Framework
 * Copyright (C) 1997 Clark Verbrugge
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the
 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
 * Boston, MA 02111-1307, USA.
 */

/*
 * Modified by the Sable Research Group and others 1997-1999.  
 * See the 'credits' file distributed with Soot for the complete list of
 * contributors.  (Soot is distributed at http://www.sable.mcgill.ca/soot)
 */







package soot.coffi;
/** Instruction subclasses are used to represent parsed bytecode; each
 * bytecode operation has a corresponding subclass of Instruction.
 * 
 * Each subclass is derived from one of
 * 
Instruction
 * Instruction_noargs (an Instruction with no embedded arguments)
 * Instruction_byte (an Instruction with a single byte data argument)
 * Instruction_bytevar (a byte argument specifying a local variable)
 * Instruction_byteindex (a byte argument specifying a constant pool index)
 * Instruction_int (an Instruction with a single short data argument)
 * Instruction_intvar (a short argument specifying a local variable)
 * Instruction_intindex (a short argument specifying a constant pool index)
 * Instruction_intbranch (a short argument specifying a code offset)
 * Instruction_longbranch (an int argument specifying a code offset)
 * 
 * @author Clark Verbrugge
 * @see Instruction
 * @see Instruction_noargs
 * @see Instruction_byte
 * @see Instruction_bytevar
 * @see Instruction_byteindex
 * @see Instruction_int
 * @see Instruction_intvar
 * @see Instruction_intindex
 * @see Instruction_intbranch
 * @see Instruction_longbranch
 * @see Instruction_Unknown
 */
class Instruction_bytevar extends Instruction implements Interface_OneIntArg
{
    /**
     * arg_b needs to be short in order to contain all the possible values for an unsigned byte
     */
    public int arg_b;
    public boolean isWide;

    public Instruction_bytevar(byte c) { super(c); }
    public String toString(cp_info constant_pool[]) {
	return super.toString(constant_pool) + argsep + LOCALPREFIX + arg_b;
    }

    public int nextOffset(int curr) { return curr + 1 + ((isWide) ? 3 : 1); }

    public int parse(byte bc[],int index)
    {
        int indexbyte1 = (bc[index]) & 0xff;

        if(isWide)
        {
            int indexbyte2 = (bc[index+1]) & 0xff;

            arg_b = (indexbyte1 << 8) | indexbyte2;

            return index+2;
        }
        else
        {
            arg_b = indexbyte1;
            return index+1;
        }
    }

    public int compile(byte bc[],int index) { bc[index++] = code; bc[index++] = (byte) arg_b; return index; }

    public int getIntArg()
    {
	return arg_b;
    }
}