execute.v

`timescale 1ns / 1ps
//////////////////////////////////////////////////////////////////////////////////
// Company:
// Engineer:
//
// Create Date:    20:19:13 05/15/2019
// Design Name:
// Module Name:    EXE_STAGE
// Project Name:
// Target Devices:
// Tool versions:
// Description:
//
// Dependencies:
//
// Revision:
// Revision 0.01 - File Created
// Additional Comments:
//
//////////////////////////////////////////////////////////////////////////////////
module execute(exe_aluc,exe_a,exe_b,exe_imm,
               exe_a_select, exe_b_select,
               mem_forward, wb_alu_forward, wb_mo_forward, wb_m2reg,
               exe_alu,z);
//ea-由寄存器读出的操作数a；eb-由寄存器读出的操作数a；eimm-经过扩展的立即数；
input [31:0] exe_a,exe_b,exe_imm;
input [31:0] mem_forward, wb_alu_forward, wb_mo_forward; // 前推数据
input wb_m2reg;
input [2:0] exe_aluc; 	//ALU控制码
input [1:0] exe_a_select,exe_b_select;  //ALU输入操作数的多路选择器
output [31:0] exe_alu;  //alu操作输出
output z;  // zero flag

wire [31:0] alua,alub,sa;

assign sa={27'b0,exe_imm[9:5]};//移位位数的生成

wire [31:0] wb_data;

mux32_2_1 wb_data_mux(wb_alu_forward, wb_mo_forward, wb_m2reg, wb_data);

mux32_4_1 alu_ina (exe_a,sa, mem_forward, wb_data,
                   exe_a_select,alua);//选择ALU a端的数据来源
mux32_4_1 alu_inb (exe_b,exe_imm, mem_forward, wb_data,
                   exe_b_select,alub);//选择ALU b端的数据来源

alu al_unit (alua,alub,exe_aluc,exe_alu,z);//ALU

endmodule