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-----------------------------------------------------------------------

-- This file is part of SCARTS.

-- 

-- SCARTS is free software: you can redistribute it and/or modify

-- it under the terms of the GNU General Public License as published by

-- the Free Software Foundation, either version 3 of the License, or

-- (at your option) any later version.

-- 

-- SCARTS is distributed in the hope that it will be useful,

-- but WITHOUT ANY WARRANTY; without even the implied warranty of

-- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

-- GNU General Public License for more details.

-- 

-- You should have received a copy of the GNU General Public License

-- along with SCARTS.  If not, see <http://www.gnu.org/licenses/>.

-----------------------------------------------------------------------

-------------------------------------------------------------------------

--

-- Filename: math_pkg.vhd

-- =========

--

-- Short Description:

-- ==================

--   Utility Package defining often used mathematical functions

--

-------------------------------------------------------------------------

package math_pkg is

  -- Calculates the logarithm dualis of the operand and rounds up

  -- the result to the next integer value.

  function log2c(constant value : in integer) return integer;

  -- Returns the maximum of the two operands

  function max(constant value1, value2 : in integer) return integer;

  -- Returns the maximum of the three operands

  function max(constant value1, value2, value3 : in integer) return integer;

end math_pkg;

package body math_pkg is

  function log2c(constant value : in integer) return integer is

    variable ret_value : integer;

    variable cur_value : integer;

  begin

    ret_value := 0;

    cur_value := 1;

    while cur_value < value loop

      ret_value := ret_value + 1;

      cur_value := cur_value * 2;

    end loop;

    return ret_value;

  end function log2c;

  function max(constant value1, value2 : in integer) return integer is

    variable ret_value : integer;

  begin

    if value1 > value2 then

      ret_value := value1;

    else

      ret_value := value2;

    end if;

    return ret_value;

  end function max;

  function max(constant value1, value2, value3 : in integer) return integer is

  begin

    return max(max(value1, value2), value3);

  end function max;

 end package body math_pkg;