alu.h

SystemC 实现 MIPS 处理器 源代码

#ifndef ALU_H
#define ALU_H

#include "STDAFX.h"

SC_MODULE(ALU)
{
	//输入的两个计算数
	sc_in<sc_uint<32> > A,B;
	//计算函数
	sc_in<sc_uint<6> > ALUC;
	//计算结果
	sc_out<sc_uint<32> > R;

	void cal()
	{
		unsigned int aluc= ALUC.read().to_uint();		
		sc_uint<32> out;
		//判断计算类型
		switch(aluc)
		{
			//add
			case 32:
				out=A.read()+B.read();
				R.write(out);
				break;
			//sub
			case 34:
				out=A.read()-B.read();
				R.write(out);
				break;
			//and
			case 36:
				out=A.read().to_uint() & B.read().to_uint();
				R.write(out);
				break;
			//or
			case 37:
				out=A.read().to_uint() | B.read().to_uint();
				R.write(out);
				break;
			//sll
			case 0:
				//此时 sa=A;
				
				out=B.read();
				if (A.read()[4]==1) out=out<<16;
				if (A.read()[3]==1) out=out<<8;
				if (A.read()[2]==1) out=out<<4;
				if (A.read()[1]==1) out=out<<2;
				if (A.read()[0]==1) out=out<<1;
				R.write(out);

				break;

			//srl
			case 2:
				out=B.read();
				if (A.read()[4]==1) out=out>>16;
				if (A.read()[3]==1) out=out>>8;
				if (A.read()[2]==1) out=out>>4;
				if (A.read()[1]==1) out=out>>2;
				if (A.read()[0]==1) out=out>>1;
				R.write(out);
				break;

			//sra
			case 3:
				out=B.read();
				int sign=B.read()[31];

				if (A.read()[4]==1) { out=out>>16; if (sign==1) out=out | 0xffff0000; }
				if (A.read()[3]==1) { out=out>>8; if (sign==1) out=out | 0xff000000; }
				if (A.read()[2]==1) { out=out>>4; if (sign==1) out=out | 0xf0000000; }
				if (A.read()[1]==1) { out=out>>2; if (sign==1) out=out | 3221225472; }
				if (A.read()[0]==1) { out=out>>1; if (sign==1) out=out | 2147483648; }
				R.write(out);
				break;
		}
	}

	SC_CTOR(ALU)
	{	
		SC_METHOD(cal);
		sensitive<<A<<B<<ALUC;
	}
};

/*
SC_MODULE(test_ALU)
{
	sc_out<sc_uint<32> > A,B;
	sc_out<sc_uint<6> > ALUC;
	sc_in<sc_uint<32> > R;
	sc_in<bool> isZero;

	void test()
	{
		int i;

		cout<<"ALU TEST BEGIN!"<<endl;

		//测试加法
		A.write(100);
		B.write(200);
		ALUC.write(32);
		wait();
		Print(A.read());
		Print(B.read());
		Print(ALUC.read(),0);
		Print(R.read());
		cout<<isZero<<endl;

		cout<<endl;

		//测试加法2
		A.write(4000000000);
		B.write(4000000000);
		ALUC.write(32);
		wait();
		Print(A.read());
		Print(B.read());
		Print(ALUC.read(),0);
		Print(R.read());

		cout<<endl;

		//测试减法
		A.write(200);
		B.write(200);
		ALUC.write(34);
		wait();
		Print(A.read());
		Print(B.read());
		Print(ALUC.read(),0);
		Print(R.read());
		cout<<isZero<<endl;

		cout<<endl;

		//测试sll移位
		A.write(7);
		B.write(200);
		ALUC.write(0);
		wait();
		Print(A.read());
		Print(B.read());
		Print(ALUC.read(),0);
		Print(R.read());

		cout<<endl;
		//测试sra移位
		A.write(7);
		B.write(4043308928);
		ALUC.write(3);
		wait();
		Print(A.read());
		Print(B.read());
		Print(ALUC.read(),0);
		Print(R.read());
	}

	SC_CTOR(test_ALU)
	{
		SC_THREAD(test);
		sensitive<<R;
		//dont_initialize();
	}
};

void ALU_test()
{
	ALU alu("ALU");
	test_ALU test("test_ALU");

	sc_signal<sc_uint<32> > A,B,R;
	sc_signal<sc_uint<6> > ALUC;
	sc_signal<bool> isZero;

	alu.A(A);
	alu.B(B);
	alu.R(R);
	alu.ALUC(ALUC);
	alu.isZero(isZero);

	test.A(A);
	test.B(B);
	test.R(R);
	test.ALUC(ALUC);
	test.isZero(isZero);

	sc_start(100);
}

*/

#endif