Subversion Repositories System09

library IEEE;

   use IEEE.std_logic_1164.all;

   use IEEE.std_logic_arith.all;

   use IEEE.std_logic_unsigned.all;

package bit_funcs is

   function log2(v: in natural) return natural;

   function pow2(v: in natural) return natural;

end package bit_funcs;

package body bit_funcs is

   function log2(v: in natural) return natural is

      variable i: natural;

      variable n: natural;

      variable logn: natural;

   begin

      n := 1;

      for i in 0 to 128 loop

         logn := i;

         exit when (n>=v);

         n := n * 2;

      end loop;

      return logn;

   end function log2;

   function pow2(v: in natural) return natural is

      variable i: natural;

      variable pown: natural;

   begin

      pown := 1;

      for i in 0 to v loop

         exit when (i=v);

         pown := pown * 2;

      end loop;

      return pown;

   end function pow2;

end package body bit_funcs;