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/*
* Utility functions
*
* Copyright (c) 2015 Michael Buesch <m@bues.ch>
*
* 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.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#include "util.h"
int32_t pow_int(int16_t b, uint8_t e)
{
int32_t x, y;
if (!e)
return 1;
x = b;
while (!(e & 1)) {
e = (uint8_t)(e >> 1);
x *= x;
}
y = x;
e = (uint8_t)(e >> 1);
while (e) {
x *= x;
if (e & 1)
y *= x;
e = (uint8_t)(e >> 1);
}
return y;
}
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