sparcregister.java

用Java实现的编译器。把源代码编译成SPARC汇编程序

// $Id: SPARCRegister.java,v 1.5 2000/10/21 23:18:10 mdeeds Exp $

package java6035.tools.ASM;

/**
 * SPARC Register represents a register in SPARC.
 * Only the user accessable registers may be created and used.
 * System registers will cause problems.
 * 
 * Valid register numbers are from 0 to 31 inclusive
 **/

public class SPARCRegister extends SPARCOperand
{
    protected int sparc_op_kind() { return SPARCREGISTER; }

    public int status;
	/**
     * Returns true if @param o represents the same register
     * as this.
     **/
    public boolean equals(Object o)
    {
	if (o instanceof SPARCRegister &&
	    this.w == ((SPARCRegister)o).w)
	    return true;
	return false;
    }

    /**
     * Returns a hash code which is the same for any two SPARCRegisters
     * which are equal to each other.  (i.e. the same register)
     **/
    public int hashCode() {
	return this.w;
    }


    /**
     * Returns true if this object represents the register identified by
     * the symbolic constant given.
     */
	 
    public boolean equals(int r)
    {
	return w == r;
    }


    /**
     * Returns which register this object represents.
     */
	 
    public int which()
    {
	return w;
    }


    /**
     * Returns the string representation of the register.
     */
	 
    public String toString()
    {
	return stringrep[w];
    }


    SPARCRegister(int which)
    {
	this.w = which;
    }


    private int w;

    private static String stringrep[] = 
    	{"%g0","%g1","%g2","%g3","%g4","%g5","%g6","%g7",
         "%o0","%o1","%o2","%o3","%o4","%o5","%sp","%o7",
	 	 "%l0","%l1","%l2","%l3","%l4","%l5","%l6","%l7",
	 	 "%i0","%i1","%i2","%i3","%i4","%i5","%fp","%i7"};


    /** Global register g0: mapped to constant 0 */
    public static final int G0 = 0;
    /** register 0: mapped to constant 0 */
    public static final SPARCRegister g0 = new SPARCRegister(G0);

    /** Global register 1 */
    public static final int G1 = 1;
    /** Global register 1 */
    public static final SPARCRegister g1 = new SPARCRegister(G1);

    /** Global register 2 */
    public static final int G2 = 2;
    /** Global register 2 */
    public static final SPARCRegister g2 = new SPARCRegister(G2);
    
    /** Global register 3 */
    public static final int G3 = 3;
    /** Global register 3 */
    public static final SPARCRegister g3 = new SPARCRegister(G3);
    
    /** Global register 4 */
    public static final int G4 = 4;
    /** Global register 4 */
    public static final SPARCRegister g4 = new SPARCRegister(G4);
    
    /** Global register 5 */
    public static final int G5 = 5;
    /** Global register 5 */
    public static final SPARCRegister g5 = new SPARCRegister(G5);
    
    /** Global register 6 */
    public static final int G6 = 6;
    /** Global register 6 */
    public static final SPARCRegister g6 = new SPARCRegister(G6);
    
    /** Global register 7 */
    public static final int G7 = 7;
    /** Global register 7 */
    public static final SPARCRegister g7 = new SPARCRegister(G7);
    
    /** Output register 0 */
    public static final int O0 = 8;
    /** Output register 0 */
    public static final SPARCRegister o0 = new SPARCRegister(O0);
    
    /** Output register 1 */
    public static final int O1 = 9;
    /** Output register 1 */
    public static final SPARCRegister o1 = new SPARCRegister(O1);
    
    /** Output register 2 */
    public static final int O2 = 10;
    /** Output register 2 */
    public static final SPARCRegister o2 = new SPARCRegister(O2);
    
    /** Output register 3 */
    public static final int O3 = 11;
    /** Output register 3 */
    public static final SPARCRegister o3 = new SPARCRegister(O3);
    
    /** Output register 4 */
    public static final int O4 = 12;
    /** Output register 4 */
    public static final SPARCRegister o4 = new SPARCRegister(O4);
    
	/** Output register 5 */
    public static final int O5 = 13;
	/** Output register 5 */
    public static final SPARCRegister o5 = new SPARCRegister(O5);
    
	/** Stack Pointer register synonym of out register 6 */
    public static final int SP = 14;
	/** Stack Pointer register synonym of out register 6 */
    public static final SPARCRegister sp = new SPARCRegister(SP);
    
	/** Output register 7 */
    public static final int O7 = 15;
	/** Output register 7 */
    public static final SPARCRegister o7 = new SPARCRegister(O7);
    
	/** Local register 0 */
    public static final int L0 = 16;
	/** Local register 0 */
    public static final SPARCRegister l0 = new SPARCRegister(L0);
    
	/** Local register 1 */
    public static final int L1 = 17;
	/** Local register 1 */
    public static final SPARCRegister l1 = new SPARCRegister(L1);
	
	/** Local register 2 */
    public static final int L2 = 18;
	/** Local register 2 */
    public static final SPARCRegister l2 = new SPARCRegister(L2);
	
	/** Local register 3 */
    public static final int L3 = 19;
	/** Local register 3 */
    public static final SPARCRegister l3 = new SPARCRegister(L3);
	
	/** Local register 4 */
    public static final int L4 = 20;
	/** Local register 4 */
    public static final SPARCRegister l4 = new SPARCRegister(L4);
    
	/** Local register 5 */
    public static final int L5 = 21;
	/** Local register 5 */
    public static final SPARCRegister l5 = new SPARCRegister(L5);
    
	/** Local register 6 */
    public static final int L6 = 22;
	/** Local register 6 */
    public static final SPARCRegister l6 = new SPARCRegister(L6);
    
	/** Local register 7 */
    public static final int L7 = 23;
	/** Local register 7 */
    public static final SPARCRegister l7 = new SPARCRegister(L7);
    
	/** Input register 0 */
    public static final int I0 = 24;
	/** Input register 0 */
    public static final SPARCRegister i0 = new SPARCRegister(I0);
    
	/** Input register 1 */
    public static final int I1 = 25;
	/** Input register 1 */
    public static final SPARCRegister i1 = new SPARCRegister(I1);
    
	/** Input register 2 */
    public static final int I2 = 26;
	/** Input register 2 */
    public static final SPARCRegister i2 = new SPARCRegister(I2);
    
	/** Input register 3 */
    public static final int I3 = 27;
	/** Input register 3 */
    public static final SPARCRegister i3 = new SPARCRegister(I3);
    
	/** Input register 4 */
    public static final int I4 = 28;
	/** Input register 4 */
    public static final SPARCRegister i4 = new SPARCRegister(I4);
    
	/** Input register 5 */
    public static final int I5 = 29;
	/** Input register 5 */
    public static final SPARCRegister i5 = new SPARCRegister(I5);
    
    /** frame pointer */
    public static final int FP = 30;
    /** frame pointer */
    public static final SPARCRegister fp = new SPARCRegister(FP);
    
	/** Input register 7 */
    public static final int I7 = 31;
	/** Input register 7*/
    public static final SPARCRegister i7 = new SPARCRegister(I7);


    private static SPARCRegister regs[] = 
    	{g0,g1,g2,g3,g4,g5,g6,g7,
	 	 o0,o1,o2,o3,o4,o5,sp,o7,
	     l0,l1,l2,l3,l4,l5,l6,l7,
	     i0,i1,i2,i3,i4,i5,fp,i7};

    /** return register the given register number points to **/
    public static SPARCRegister getRegister(int reg)
    {
		if (reg < 0 || reg > 31 || reg == 1 || reg == 26 || reg == 27)
		    throw new ASMException("Illegal register "+reg);
		return regs[reg];
    }

	public static void releaseRegister(SPARCRegister reg){
		reg.status = 0;
	}

	public static void setRegister(SPARCRegister reg){
		reg.status = 1;
	}

	public static SPARCRegister getNextRegInput(){
		for(int j=24 ; j<=31; j++){
			if( (regs[j].which() != 30) && (regs[j].status != 1)){
				return regs[j];
			}
		}
		return null;
	}
	
	public static SPARCRegister getNextRegOutput(){
		for(int j=8 ; j<=15; j++){
			if( (regs[j].which() != 14) && (regs[j].status != 1)){
				return regs[j];
			}
		}
		return null;
	}
	
	public static SPARCRegister getNextRegLocal(){
		for(int j=16 ; j<=23; j++){
			if( regs[j].status != 1 ){
				return regs[j];
			}
		}
		return null;
	}


	public static int getLocalAvailable(){
		int cnt = 0;
		for(int j=16 ; j<=23; j++){
			if( regs[j].status != 1 ){
				cnt++;
			}
		}
		return cnt;
	}
	
	public static void releaseAllRegisters(){
		for(int j=0; j<=31; j++){
			if( (regs[j].which() != 14) && (regs[j].which() != 30) ){
				regs[j].status = 0;
			}
		}
	}

	public static void releaseAllOutputRegisters(){
		for(int j=8; j<=15; j++){
			if( regs[j].which() != 14 ){
				regs[j].status = 0;
			}
		}
	}

	public static int noOfOutputRegistersUsed(){
		int cnt = 0;
		for(int j=8; j<=15; j++){
			if( (regs[j].which() != 14)  && (regs[j].status == 1)){
				cnt++;
			}
		}
		return cnt;
	}

}