You cannot select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
microwatt/utils.vhdl

48 lines
1.0 KiB
VHDL

library ieee;
use ieee.std_logic_1164.all;
use ieee.numeric_std.all;
package utils is
function log2(i : natural) return integer;
function log2ceil(i : natural) return integer;
function ispow2(i : integer) return boolean;
end utils;
package body utils is
function log2(i : natural) return integer is
variable tmp : integer := i;
variable ret : integer := 0;
begin
while tmp > 1 loop
ret := ret + 1;
tmp := tmp / 2;
end loop;
return ret;
end function;
function log2ceil(i : natural) return integer is
variable tmp : integer := i;
variable ret : integer := 0;
begin
while tmp >= 1 loop
ret := ret + 1;
tmp := tmp / 2;
end loop;
return ret;
end function;
function ispow2(i : integer) return boolean is
begin
if to_integer(to_unsigned(i, 32) and to_unsigned(i - 1, 32)) = 0 then
return true;
else
return false;
end if;
end function;
end utils;