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//// Copyright (C) 2015 Authors and OPENCORES.ORG                 ////

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//////////////////////////////////////////////////////////////////////

module

  one_hot_encoder

  #(

    A,  // encoder select width

    D = 2 ** A

  )

  (

    input   [A-1:0] select,

    output  [D-1:0] encoded

  );

  // --------------------------------------------------------------------

  //

  localparam W = 2 ** (A-1);

  // --------------------------------------------------------------------

  //

  generate

    if(A == 1)

    begin: one_hot_encoder_gen

        assign encoded[1:0] = select[0] ? 2'b10 :2'b01;

    end

    else

    begin: recurse_one_hot_encoder_gen

      wire [W-1:0] encoder_out;

      one_hot_encoder #(.A(A - 1))

        one_hot_encoder_i

        (

          .select(select[A-2:0]),

          .encoded(encoder_out)

        );

      assign encoded = select[A-1] ? {encoder_out, {W{1'b0}}} : {{W{1'b0}}, encoder_out};

    end

  endgenerate

// --------------------------------------------------------------------

//

endmodule