instruction.cpp

浙江大学的悟空嵌入式系统模拟器

/*
*  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    Arch/MU0/Instruction.cpp
*
*  $Id: Instruction.cpp,v 1.2 2005/02/21 09:53:26 kehc Exp $
*
*  \author  
*/
//=============================================================================

#include "stdafx.h"
#include "./Instruction.h"
#include "./Processor.h"

namespace MU0 { 

	DEFINE_SINGLETON(Instruction)

		DEFINE_SINGLETON(Instruction_Set)

		CPU & Instruction::get_cpu(void) const
	{
		return (CPU&)(*cpu_);
	}



	void Instruction::on_LDA(int op, int operand)
	{
		Core::Bytecode_Type buffer;
		Core::u16 val;

		get_cpu().get_mmu().access(Core::Memory_16Bit::MEMORY_READ, operand, 2, buffer);
		Core::Wukong_Get_System().convert_from_bytecode(buffer, val);
		get_cpu().write_register(CPU::ACC, val);
	}
	void Instruction::on_STO(int op, int operand)
	{
		Core::Bytecode_Type buffer;
		Core::Register_Int val;
		get_cpu().read_register(CPU::ACC, val);
		Core::Wukong_Get_System().convert_to_bytecode((Core::u16)val, buffer);
		get_cpu().get_mmu().access(Core::Memory_16Bit::MEMORY_WRITE, operand, 2, buffer);
	}
	void Instruction::on_ADD(int op, int operand)
	{
		Core::Bytecode_Type buffer;
		Core::u16 val;
		Core::Register_Int old_val;
		get_cpu().read_register(CPU::ACC, old_val);
		get_cpu().get_mmu().access(Core::Memory_16Bit::MEMORY_READ, operand, 2, buffer);
		Core::Wukong_Get_System().convert_from_bytecode(buffer, val);
		get_cpu().write_register(CPU::ACC, (Core::u16)old_val + val);
	}
	void Instruction::on_SUB(int op, int operand)
	{
		Core::Bytecode_Type buffer;
		Core::u16 val;
		Core::Register_Int old_val;
		get_cpu().read_register(CPU::ACC, old_val);
		get_cpu().get_mmu().access(Core::Memory_16Bit::MEMORY_READ, operand, 2, buffer);
		Core::Wukong_Get_System().convert_from_bytecode(buffer, val);
		get_cpu().write_register(CPU::ACC, (Core::u16)old_val - val);
	}
	void Instruction::on_JMP(int op, int operand)
	{
		Core::Bytecode_Type buffer;
		get_cpu().set_pc((Core::u16)operand);
	}
	void Instruction::on_JGE(int op, int operand)
	{
		Core::Bytecode_Type buffer;
		Core::u16 val;
		get_cpu().get_mmu().access(Core::Memory_16Bit::MEMORY_READ, operand, 2, buffer);
		Core::Wukong_Get_System().convert_from_bytecode(buffer, val);
		if (val >= 0)
		{
			get_cpu().set_pc((Core::u16)operand);
		}
	}	

	void Instruction::on_JNE(int op, int operand)
	{
		Core::Bytecode_Type buffer;
		Core::u16 val;
		get_cpu().get_mmu().access(Core::Memory_16Bit::MEMORY_READ, operand, 2, buffer);
		Core::Wukong_Get_System().convert_from_bytecode(buffer, val);
		if (val != 0)
		{
			get_cpu().set_pc((Core::u16)operand);
		}
	}
	void Instruction::on_STP(int op, int operand)
	{
		get_cpu().stop();
	}

	void Instruction::execute(Core::Instruction_Unit binary)
	{
		Core::Binary_16Bit bits((Core::u16)binary);
		int op = bits.convert_to_int(12, 15);
		int operand = bits.convert_to_int(0, 11);

		switch (op)
		{
		case LDA:
			on_LDA(op, operand);
			break;
		case STO:
			on_STO(op, operand);
			break;
		case ADD:
			on_ADD(op, operand);
			break;
		case SUB:
			on_SUB(op, operand);
			break;
		case JMP:
			on_JMP(op, operand);
			break;
		case JGE:
			on_JGE(op, operand);
			break;
		case JNE:
			on_JNE(op, operand);
			break;
		case STP:
			on_STP(op, operand);
			break;
		default:
			assert(0);
			break;
		};
	}

	void Instruction_Set::register_instructions()
	{
		register_instruction(MU0::Instruction::instance());
	}

	Core::Instruction *  Instruction_Set::classify(Core::Instruction_Unit binary)
	{
		return instructions_[0];
	}

}