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/* fixed_sqrt_ui32.c */
/* avr.math.fixed - Fixed point math module. {{{
 *
 * Copyright (C) 2005 Nicolas Schodet
 *
 * Robot APB Team/Efrei 2006.
 *        Web: http://assos.efrei.fr/robot/
 *      Email: robot AT efrei DOT fr
 *
 * This program 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 2 of the License, or
 * (at your option) any later version.
 * 
 * This program 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 this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 *
 * }}} */
#include "common.h"
#include "fixed.h"

/** Compute square root, ui32 -> ui16. */
uint16_t
fixed_sqrt_ui32 (uint32_t x)
{
    uint32_t root, bit, test;
    root = 0;
    bit = 1L << 30;
    do
      {
	test = root + bit;
	if (x >= test)
	  {
	    x -= test;
	    root = test + bit;
	  }
	root >>= 1;
	bit >>= 2;
      } while (bit);
    return root;
}