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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;