sparcaddress.java

来自「用Java实现的编译器。把源代码编译成SPARC汇编程序」· Java 代码 · 共 215 行

// $Id: SPARCAddress.java,v 1.4 1999/11/04 16:53:41 deberg Exp $

package java6035.tools.ASM;

/**
 * SPARCAddress
 *
 * represents an address in SPARC. There are four formats of address:
 * (register), imm, imm(register), symbol
 */

public class SPARCAddress extends SPARCOperand
{
    protected int sparc_op_kind() { return SPARCADDRESS; }

 	/** 
     *  the address label (usually for branch instructions)
	 *	null if address in other formats
	 *
     */
    protected String symbol;


    /** 
     * base address register 1, null if address is simm13 or label format
	 *
     */
    protected SPARCRegister r1;

    /** 
     * base address register 2, null if address is simm13 or label format
     */
    protected SPARCRegister r2;


    /** 
     * 	immediate offset or address (depending on format)
	 *	; disregarded or arbitrary if the address is label format
     */
	 
    protected int imm;

    public final boolean isImmed() 
    { 
	return false; 
    }
   
    public final boolean isRegister() 
    { 
	return false; 
    }

    public final boolean isAddress()
    {
	return true;
    }


    /** 
     * returns the first base register  of the address, null if address is
     * pure simm13 format 
     */
    public SPARCRegister getRegister1()
    {
		return r1;
    }

    /** 
     * returns the 
     */
    public String getSymbol()
    {
		return symbol;
    }
	
	/** 
     * returns the second base register  of the address, null if address is
     * pure simm13 format 
     */
    public SPARCRegister getRegister2()
    {
		return r2;
    }

    /** 
     * returns the immed offset of the address, 
	 * which is disregarded or arbitrary if
	 * address format is (reg+reg)
     */
    public int getImmed()
    {
		return imm;
    }

    /**
     * Constructor for address of the form reg.only
     */
    public SPARCAddress (SPARCRegister r)
    {
		if (r == null) throw new ASMException
		    ("SPARCAddress: in constructor: register r must not be null");
		this.imm = 0;
		this.r1 = r;
		this.r2 = null;			
		symbol = null;
	}

	/**
     * Constructor for label form of address
     */
    public SPARCAddress (String s)
    {
		if (s == null) throw new ASMException
		    ("SPARCAddress: in constructor: label must not be null");
		this.imm = 0;
		this.r1 = null;
		this.r2 = null;			
		symbol = s;
	}

    /**
     * Constructor for address of the form simm13
     */
    public SPARCAddress (int i)
    {
		this.imm = i;
		this.r1 = SPARCRegister.g0;
		this.r2 = null;
		symbol = null;
    }	


    /**
     * Constructor for address of the form simm13 (+-) reg
     */
    public SPARCAddress (SPARCRegister r, int i)
    {
		if (r == null) throw new ASMException
		    ("SPARCAddress: in constructor: register r must not be null");
		this.imm = i;
		this.r1 = r;
		this.r2 = null;
		symbol = null;		
    }


    /**
     * Constructor for address of the form reg + reg
     */
    public SPARCAddress (SPARCRegister r1, SPARCRegister r2)
    {
		if (r1 == null) throw new ASMException
		    ("SPARCAddress: in constructor: register must not be null");
		if (r2 == null) throw new ASMException
		    ("SPARCAddress: in constructor: register must not be null");			
		this.r1 = r1;
		this.r2 = r2;
		this.imm = 0;
		symbol = null;
    }


    /**
     * Returns the string representation of the operand.
     */
    public String toString()
    {
		if(symbol != null) return symbol;
		if(imm !=0 )
		{
			if(imm > 0)
			{
				return "["+r1.toString()+"+"+imm+"]";
			}
			else
			{
				imm = -imm;
				return "["+r1.toString()+"-"+imm+"]";			
			}
		}
		else
		{
			if(r1 != null && r2 != null)
			{
				return "["+r1.toString()+"+"+r2.toString()+"]";
			}	
			else
			{
				return "["+r1.toString()+"]";
			}
		}
    }


    /**
     * Returns true if two address are the same.
     */
    public boolean equals(Object o)
    {
		if (o instanceof SPARCAddress)
		{
		    SPARCAddress a = (SPARCAddress) o;
		    if(symbol != null)
				return symbol.equals(a.symbol);
			else
				return (a.r1.equals(r1) &&
						a.r2.equals(r2) &&
						a.imm == imm);
		}
		return false;
    }
}