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import fp_wire::*;

module fp_cmp (
    input  fp_cmp_in_type  fp_cmp_i,
    output fp_cmp_out_type fp_cmp_o
);
  logic [64:0] data1;
  logic [64:0] data2;
  logic [2:0] rm;
  logic [9:0] class1;
  logic [9:0] class2;

  logic comp_lt;
  logic comp_le;
  logic [63:0] result;
  logic [4:0] flags;

  always_comb begin

    data1 = fp_cmp_i.data1;
    data2 = fp_cmp_i.data2;
    rm = fp_cmp_i.rm;
    class1 = fp_cmp_i.class1;
    class2 = fp_cmp_i.class2;

    comp_lt = 0;
    comp_le = 0;
    result = 0;
    flags = 0;

    if ((rm == 0) || (rm == 1) || (rm == 2)) begin
      comp_lt = (data1[63:0] < data2[63:0]) ? 1'b1 : 1'b0;
      comp_le = (data1[63:0] <= data2[63:0]) ? 1'b1 : 1'b0;
    end

    if (rm == 2) begin  //feq
      if ((class1[8] | class2[8]) == 1) begin
        flags[4] = 1;
      end else if ((class1[9] | class2[9]) == 1) begin
        flags[0] = 0;
      end else if (((class1[3] | class1[4]) & (class2[3] | class2[4])) == 1) begin
        result[0] = 1;
      end else if (data1 == data2) begin
        result[0] = 1;
      end
    end else if (rm == 1) begin  //flt
      if ((class1[8] | class2[8] | class1[9] | class2[9]) == 1) begin
        flags[4] = 1;
      end else if (((class1[3] | class1[4]) & (class2[3] | class2[4])) == 1) begin
        result[0] = 0;
      end else if ((data1[64] ^ data2[64]) == 1) begin
        result[0] = data1[64];
      end else begin
        if (data1[64] == 1) begin
          result[0] = ~comp_le;
        end else begin
          result[0] = comp_lt;
        end
      end
    end else if (rm == 0) begin  //fle
      if ((class1[8] | class2[8] | class1[9] | class2[9]) == 1) begin
        flags[4] = 1;
      end else if (((class1[3] | class1[4]) & (class2[3] | class2[4])) == 1) begin
        result[0] = 1;
      end else if ((data1[64] ^ data2[64]) == 1) begin
        result[0] = data1[64];
      end else begin
        if (data1[64] == 0) begin
          result[0] = comp_le;
        end else begin
          result[0] = ~comp_lt;
        end
      end
    end

    fp_cmp_o.result = result;
    fp_cmp_o.flags  = flags;

  end

endmodule