71 lines
1.7 KiB
C++
71 lines
1.7 KiB
C++
/*
|
|
* Licensed under the Apache License, Version 2.0 (the "License");
|
|
* you may not use this file except in compliance with the License.
|
|
* You may obtain a copy of the License at
|
|
*
|
|
* http://www.apache.org/licenses/LICENSE-2.0
|
|
*
|
|
* Unless required by applicable law or agreed to in writing, software
|
|
* distributed under the License is distributed on an "AS IS" BASIS,
|
|
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
* See the License for the specific language governing permissions and
|
|
* limitations under the License.
|
|
*
|
|
* Copyright 2011 Danny Robson <danny@nerdcruft.net>
|
|
*/
|
|
|
|
#ifndef __UTIL_BITWISE_HPP
|
|
#define __UTIL_BITWISE_HPP
|
|
|
|
#include <cstdint>
|
|
|
|
#include "debug.hpp"
|
|
|
|
const uint8_t BITMASK_1BITS = 0x01;
|
|
const uint8_t BITMASK_2BITS = 0x03;
|
|
const uint8_t BITMASK_3BITS = 0x07;
|
|
const uint8_t BITMASK_4BITS = 0x0F;
|
|
const uint8_t BITMASK_5BITS = 0x1F;
|
|
const uint8_t BITMASK_6BITS = 0x3F;
|
|
const uint8_t BITMASK_7BITS = 0x7F;
|
|
const uint8_t BITMASK_8BITS = 0xFF;
|
|
|
|
#define MODT(x) ((x) % (sizeof (T) * 8))
|
|
|
|
template <typename T>
|
|
constexpr T
|
|
rotatel (const T &value, size_t magnitude) {
|
|
return (value << MODT (magnitude)) |
|
|
(value >> sizeof (value) * 8 - MODT (magnitude));
|
|
}
|
|
|
|
|
|
template <typename T>
|
|
constexpr T
|
|
rotater (const T &value, size_t magnitude) {
|
|
return (value >> MODT (magnitude)) |
|
|
(value << sizeof (value) * 8 - MODT (magnitude));
|
|
}
|
|
|
|
#undef MODT
|
|
|
|
// TODO: make constexpr for C++14
|
|
template <typename T>
|
|
T
|
|
reverse (T value) {
|
|
T out = value;
|
|
|
|
size_t bits = sizeof (value) * 8 - 1;
|
|
for (value >>= 1; value; value >>= 1) {
|
|
out <<= 1;
|
|
out |= value & 0x01;
|
|
--bits;
|
|
}
|
|
|
|
out <<= bits;
|
|
return out;
|
|
}
|
|
|
|
#endif
|
|
|