Subversion Repositories distributed_intelligence

--      Package File Template

--

--      Purpose: This package defines useful functions

library IEEE;

use IEEE.STD_LOGIC_1164.all;

package MY_FUNCS is

        -- Operator sll and srl for a std_logic_vector

        function "sll"(val : std_logic_vector; shift : integer) return std_logic_vector;

        function "srl"(val : std_logic_vector; shift : integer) return std_logic_vector;

end MY_FUNCS;

package body MY_FUNCS is

  function "sll"(val : std_logic_vector; shift : integer) return std_logic_vector is

    variable ret : std_logic_vector(val'range) := val;

  begin

    if (shift > 0) then

      for i in 1 to shift loop

        ret := ret(val'high - 1 downto val'low) & '0';

      end loop;

    end if;

    return ret;

  end;

  function "srl"(val : std_logic_vector; shift : integer) return std_logic_vector is

    variable ret : std_logic_vector(val'range) := val;

  begin

    if (shift > 0) then

      for i in 1 to shift loop

        ret := '0' & ret(val'high downto val'low + 1) ;

      end loop;

    end if;

    return ret;

  end;

end MY_FUNCS;