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/*
* The MIT License (MIT)
*
* Copyright (c) 2015 Evan Teran
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in all
* copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
#ifndef UTILITIES_BITWISE_HPP_
#define UTILITIES_BITWISE_HPP_
#include <climits> // for CHAR_BIT
namespace bitwise {
/*
* the reason why we need the "mask" constant is
* because some platforms make >> on negative values
* arithmetic (which shifts in the sign bit, not 0)
* using the mask allows this to work with both signed
* and unsigned types
*/
template <class T>
T rotate_left(T v, int n) {
static const unsigned int bits = CHAR_BIT * sizeof(T);
const T mask = ~(T(-1) << n);
return (v << n) | ((v >> (bits - n)) & mask);
}
template <class T>
T rotate_right(T v, int n) {
return rotate_left(v, -n);
}
}
#endif