Logical Shift Left by 1

library ieee;

use ieee.std_logic_1164.all;

entity lshift is

   port ( din : in std_logic_vector(7 downto 0);

             shift_en: in std_logic;

            dout: out std_logic_vector(7 downto 0)

  );

end lshift;

architecture brute_force of lshift  is

begin

process (din, shift_en)

begin

      dout <= din;     -- default case

      if (shift_en = '1') then

           dout(0) <= '0';     -- shift a zero into LSB

           dout (1) <= din(0);

           dout (2) <= din(1);

           dout (3) <= din(2);

           dout (4) <= din(3);

           dout (5) <= din(4);

           dout (6) <= din(5);

           dout (7) <= din(6);

       end if;   

end process;

end brute_force;

end lshift;

This is one way to do it; surely there is a better way?

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