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/*
* Copyright © 2011 Keith Packard <keithp@keithp.com>
*
* 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; version 2 of the License.
*
* 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.
*/
#ifndef AO_FLIGHT_TEST
#include "ao.h"
#endif
/* Adapted from int_sqrt.c in the linux kernel, which is licensed GPLv2 */
/**
* int_sqrt - rough approximation to sqrt
* @x: integer of which to calculate the sqrt
*
* A very rough approximation to the sqrt() function.
*/
uint32_t
ao_sqrt(uint32_t op)
{
uint32_t res = 0;
uint32_t one = 1UL << (sizeof (one) * 8 - 2);
while (one > op)
one >>= 2;
while (one != 0) {
if (op >= res + one) {
op = op - (res + one);
res = res + 2 * one;
}
res /= 2;
one /= 4;
}
return res;
}
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