parser.cpp

浙江大学的悟空嵌入式系统模拟器

/* -*- C++ -*- */

/**
 *  Copyright (c) 2005 Zhejiang University, P.R.China
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program 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 for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

///==================================================
/**
 * @file        Parser.cpp
 * @brief      
 * @author      Chenfeng Zhou <[e-mail]> 
 *
 * Created    : <2005-03-02 16:31:44 by Cheney Chow>
 * Last update: <2005-03-02 16:54:18 by Cheney Chow>
 *
 * $Id: Parser.cpp,v 1.1 2005/06/16 06:01:50 qilj Exp $
 */
///==================================================


#include "Parser.h"

namespace PPC
{

    void D_Form_Parser::parse_simm (PPC_Instr_T instr,
                                    PPC_s32 &D, PPC_s32 &A, PPC_u32 &SImm)
    {
		D = (instr >> 21) & 0x1f;
		A = (instr >> 16) & 0x1f;
		SImm = instr & 0xffff;

		//! Test if it's negative;
		if (SImm & 0x8000) 
			SImm |= 0xffff0000;		//! < Sign extend
    }
    

    void D_Form_Parser::parse_uimm (PPC_Instr_T instr,
                                   PPC_s32 &D, PPC_s32 &A, PPC_u32 &UImm)
    {
		D = (instr >> 21) & 0x1f;
		A = (instr >> 16) & 0x1f;
		UImm = instr & 0xffff;
	}

    void D_Form_Parser::parse_shift16 (PPC_Instr_T instr,
                                       PPC_s32 &D, PPC_s32 &A, PPC_u32 &Imm16)
    {
		D = (instr >> 21) & 0x1f;
		A = (instr >> 16) & 0x1f;
		Imm16 = instr << 16;
	}


	void X_Form_Parser::parse_x (PPC_Instr_T instr,
								PPC_s32 &S, PPC_s32 &A, PPC_s32 &B)
	{
		S = (instr >> 21) & 0x1f;
		A = (instr >> 16) & 0x1f;
		B = (instr >> 11) & 0x1f;
	}

	void X_Form_Parser::parse_xfx (PPC_Instr_T instr,
								  PPC_s32 &S, PPC_u32 &crm)
	{
		S = (instr >> 21) & 0x1f;
		crm = (instr >> 12) & 0xff;
	}

    void X_Form_Parser::parse_xo (PPC_Instr_T instr,
                                  PPC_s32 &D, PPC_s32 &A, PPC_s32 &B)
    {
		D = (instr >> 21) & 0x1f;
		A = (instr >> 16) & 0x1f;
		B = (instr >> 11) & 0x1f;
	}

	void X_Form_Parser::parse_xl (PPC_Instr_T instr, 
								  PPC_u32 &BO, PPC_u32 &BI, PPC_u32 &BD)
	{
		BO = (instr >> 21) & 0x1f;
		BI = (instr >> 16) & 0x1f;
		BD = (instr >> 11) & 0x1f;
	}

	void X_Form_Parser::parse_xfl (PPC_Instr_T instr,
							PPC_s32 &B, PPC_u32 &fm)
	{
		B = (instr >> 11) & 0x1f;
		fm = (instr >> 17) & 0xff;
	}

	void I_Form_Parser::parse (PPC_Instr_T instr, PPC_u32 &LI)
	{
		LI = instr & 0x3fffffc;

		if (LI & 0x02000000)
			LI |= 0xfc000000; 
	}

	void B_Form_Parser::parse (PPC_Instr_T instr, PPC_u32 &BO, PPC_u32 &BD, PPC_u32 &BI)
	{
		BO = (instr >> 21) & 0x1f;
		BI = (instr >> 16) & 0x1f;
		BD = instr & 0xfffc;

		if (BD & 0x8000)
			BD |= 0xffff0000; 
	}

	void A_Form_Parser::parse (PPC_Instr_T instr,
							   PPC_s32 &D, PPC_s32 &A, PPC_s32 &B, PPC_s32 &C)
	{
		D = (instr >> 21) & 0x1f;
		A = (instr >> 16) & 0x1f;
		B = (instr >> 11) & 0x1f;
		C = (instr >> 6) & 0x1f;
	}

	void M_Form_Parser::parse (PPC_Instr_T instr,
							   PPC_s32 &S, PPC_s32 &A, PPC_s32 &SH, 
							   PPC_s32 &MB, PPC_s32 &ME)
	{
		S = (instr >> 21) & 0x1f;
		A = (instr >> 16) & 0x1f;
		SH = (instr >> 11) & 0x1f;
		MB = (instr >> 6) & 0x1f;
		ME = (instr >> 1) & 0x1f;
	}

} // namespace PPC