/*                                                                      
 Copyright 2020 Blue Liang, liangkangnan@163.com
                                                                         
 Licensed under the Apache License, Version 2.0 (the "License");         
 you may not use this file except in compliance with the License.        
 You may obtain a copy of the License at                                 
                                                                         
     http://www.apache.org/licenses/LICENSE-2.0                          
                                                                         
 Unless required by applicable law or agreed to in writing, software    
 distributed under the License is distributed on an "AS IS" BASIS,       
 WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 See the License for the specific language governing permissions and     
 limitations under the License.                                          
 */

`include "defines.v"

// 将译码结果向执行模块传递
module idu_exu(

    input wire clk,
    input wire rst_n,

    input wire[`STALL_WIDTH-1:0] stall_i,     // 流水线暂停
    input wire flush_i,                       // 流水线冲刷

    input wire[31:0] inst_i,
    input wire[`DECINFO_WIDTH-1:0] dec_info_bus_i,
    input wire[31:0] dec_imm_i,
    input wire[31:0] dec_pc_i,
    input wire[4:0] rs1_raddr_i,
    input wire[4:0] rs2_raddr_i,
    input wire[4:0] rd_waddr_i,
    input wire rd_we_i,

    output wire[31:0] inst_o,
    output wire[`DECINFO_WIDTH-1:0] dec_info_bus_o,
    output wire[31:0] dec_imm_o,
    output wire[31:0] dec_pc_o,
    output wire[4:0] rs1_raddr_o,
    output wire[4:0] rs2_raddr_o,
    output wire[4:0] rd_waddr_o,
    output wire rd_we_o

    );

    wire en = !stall_i[`STALL_EX] | flush_i;

    wire[`DECINFO_WIDTH-1:0] i_dec_info_bus = flush_i? {`DECINFO_WIDTH{1'b0}}: dec_info_bus_i;
    wire[`DECINFO_WIDTH-1:0] dec_info_bus;
    gen_en_dff #(`DECINFO_WIDTH) info_bus_ff(clk, rst_n, en, i_dec_info_bus, dec_info_bus);
    assign dec_info_bus_o = dec_info_bus;

    wire[31:0] i_dec_imm = flush_i? 32'h0: dec_imm_i;
    wire[31:0] dec_imm;
    gen_en_dff #(32) imm_ff(clk, rst_n, en, i_dec_imm, dec_imm);
    assign dec_imm_o = dec_imm;

    wire[31:0] i_dec_pc = flush_i? 32'h0: dec_pc_i;
    wire[31:0] dec_pc;
    gen_en_dff #(32) pc_ff(clk, rst_n, en, i_dec_pc, dec_pc);
    assign dec_pc_o = dec_pc;

    wire[4:0] i_rs1_raddr = flush_i? 5'h0: rs1_raddr_i;
    wire[4:0] rs1_raddr;
    gen_en_dff #(5) rs1_raddr_ff(clk, rst_n, en, i_rs1_raddr, rs1_raddr);
    assign rs1_raddr_o = rs1_raddr;

    wire[4:0] i_rs2_raddr = flush_i? 5'h0: rs2_raddr_i;
    wire[4:0] rs2_raddr;
    gen_en_dff #(5) rs2_raddr_ff(clk, rst_n, en, i_rs2_raddr, rs2_raddr);
    assign rs2_raddr_o = rs2_raddr;

    wire[4:0] i_rd_waddr = flush_i? 5'h0: rd_waddr_i;
    wire[4:0] rd_waddr;
    gen_en_dff #(5) rd_waddr_ff(clk, rst_n, en, i_rd_waddr, rd_waddr);
    assign rd_waddr_o = rd_waddr;

    wire i_rd_we = flush_i? 1'b0: rd_we_i;
    wire rd_we;
    gen_en_dff #(1) rd_we_ff(clk, rst_n, en, i_rd_we, rd_we);
    assign rd_we_o = rd_we;

    wire[31:0] i_inst = flush_i? 32'h0: inst_i;
    wire[31:0] inst;
    gen_en_dff #(32) inst_ff(clk, rst_n, en, i_inst, inst);
    assign inst_o = inst;

endmodule