ARM/Forwarding.v at master · Moridi/ARM · GitHub

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`include "Defines.v"

module Forwarding (
    input en_forwarding,
	input WB_wb_en, MEM_wb_en,
    input [`REG_ADDRESS_LEN - 1:0] MEM_dst, WB_dst, ID_src1, ID_src2,

    output [1:0] sel_src1, sel_src2,
    output ignore_hazard

);

    // reg ignore_hazard_temp;
    // reg [1:0] sel_src1_temp, sel_src2_temp;

    // assign ignore_hazard = ignore_hazard_temp;
    // assign sel_src1 = sel_src1_temp;
    // assign sel_src2 = sel_src2_temp;


    assign sel_src1 = (en_forwarding == 1'b1) ?
        (
            (MEM_wb_en && (MEM_dst == ID_src1)) ? `FORW_SEL_FROM_MEM
            : (WB_wb_en && (WB_dst == ID_src1)) ? `FORW_SEL_FROM_WB
            : 2'b0
        )
        : 2'b0;

    assign sel_src2 = (en_forwarding == 1'b1) ?
        (
            (MEM_wb_en && (MEM_dst == ID_src2)) ? `FORW_SEL_FROM_MEM
            : (WB_wb_en && (WB_dst == ID_src2)) ? `FORW_SEL_FROM_WB
            : 2'b0
        )
        : 2'b0;

    assign ignore_hazard = (en_forwarding == 1'b1) ?
        (
            (MEM_wb_en && ((MEM_dst == ID_src2) || (MEM_dst == ID_src1)))   ? 1'b1
            : (WB_wb_en && ((WB_dst == ID_src2) || (WB_dst == ID_src1)))    ? 1'b1
            : 1'b0
        )
        : 1'b0;

	// always@(*) begin
	// 	sel_src1_temp = 2'b0;
	// 	sel_src2_temp = 2'b0;
    //     ignore_hazard_temp = 1'b0;

    //     if (en_forwarding && WB_wb_en) begin
    //         if (WB_dst == ID_src1) begin
    //             sel_src1_temp = `FORW_SEL_FROM_WB;
    //             ignore_hazard_temp = 1'b1;
    //         end

    //         if (WB_dst == ID_src2) begin
    //             sel_src2_temp = `FORW_SEL_FROM_WB;
    //             ignore_hazard_temp = 1'b1;
    //         end
    //     end

    //     if (en_forwarding && MEM_wb_en) begin
    //         if (MEM_dst == ID_src1) begin
    //             sel_src1_temp = `FORW_SEL_FROM_MEM;
    //             ignore_hazard_temp = 1'b1;
    //         end

    //         if (MEM_dst == ID_src2) begin
    //             sel_src2_temp = `FORW_SEL_FROM_MEM;
    //             ignore_hazard_temp = 1'b1;
    //         end
    //     end
	// end
endmodule