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author | David Robillard <d@drobilla.net> | 2018-08-19 18:22:26 +0200 |
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committer | David Robillard <d@drobilla.net> | 2018-09-29 14:50:07 +0200 |
commit | ac65326242af579d6e1a7bd71730f1c78c8bde9b (patch) | |
tree | ae5225c4b9856b3e5d454378d00867d9b0c53d26 /chilbert/detail/operations.hpp | |
parent | 7567f77828ff9661f85eabe3b4cfb1876b307d42 (diff) | |
download | chilbert-ac65326242af579d6e1a7bd71730f1c78c8bde9b.tar.gz chilbert-ac65326242af579d6e1a7bd71730f1c78c8bde9b.tar.bz2 chilbert-ac65326242af579d6e1a7bd71730f1c78c8bde9b.zip |
Reorganize headers to make a clear public/private distinction
Diffstat (limited to 'chilbert/detail/operations.hpp')
-rw-r--r-- | chilbert/detail/operations.hpp | 168 |
1 files changed, 168 insertions, 0 deletions
diff --git a/chilbert/detail/operations.hpp b/chilbert/detail/operations.hpp new file mode 100644 index 0000000..94635b4 --- /dev/null +++ b/chilbert/detail/operations.hpp @@ -0,0 +1,168 @@ +/* + Copyright (C) 2018 David Robillard <d@drobilla.net> + Copyright (C) 2006-2007 Chris Hamilton <chamilton@cs.dal.ca> + + 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, see <https://www.gnu.org/licenses/>. +*/ + +#ifndef CHILBERT_OPERATIONS_HPP +#define CHILBERT_OPERATIONS_HPP + +#include "chilbert/detail/traits.hpp" +#include "chilbert/operators.hpp" + +#include <cassert> +#include <climits> +#include <cstddef> +#include <cstdint> +#include <type_traits> + +namespace chilbert { +namespace detail { + +/// Reset all bits in `field` +template <typename T> +std::enable_if_t<std::is_integral<T>::value> +reset_bits(T& field) +{ + field = static_cast<T>(0); +} + +/// Reset all bits in `field` +template <typename T> +std::enable_if_t<is_bitvec_v<T>> +reset_bits(T& field) +{ + field.reset(); +} + +/// Return the `index`th bit in `field` +template <typename T> +std::enable_if_t<std::is_integral<T>::value, bool> +test_bit(const T& field, const size_t index) +{ + assert(size_t(index) < sizeof(field) * CHAR_BIT); + return field & (T{1} << index); +} + +/// Return the `index`th bit in `field` +template <typename T> +std::enable_if_t<is_bitvec_v<T>, bool> +test_bit(const T& field, const size_t index) +{ + return field.test(index); +} + +/// Set the `index`th bit in `field` +template <typename T> +std::enable_if_t<std::is_integral<T>::value> +set_bit(T& field, const size_t index) +{ + assert(size_t(index) < sizeof(field) * CHAR_BIT); + field |= (T{1} << index); + assert(test_bit(field, index)); +} + +/// Set the `index`th bit in `field` to `value` +template <typename T> +std::enable_if_t<std::is_integral<T>::value> +set_bit(T& field, const size_t index, const bool value) +{ + assert(size_t(index) < sizeof(field) * CHAR_BIT); + field ^= (-T{value} ^ field) & (T{1U} << index); + assert(test_bit(field, index) == value); +} + +/// Set the `index`th bit in `field` +template <typename T> +std::enable_if_t<is_bitvec_v<T>> +set_bit(T& field, const size_t index) +{ + field.set(index); +} + +/// Set the `index`th bit in `field` to `value` +template <typename T> +std::enable_if_t<is_bitvec_v<T>> +set_bit(T& field, const size_t index, const bool value) +{ + field.set(index, value); +} + +/// Return 1 + the index of the least significant 1-bit of `field`, or zero +template <typename T> +int pop_count(const T& field); + +template <> +int +pop_count<unsigned long>(const unsigned long& field) +{ + return __builtin_popcountl(field); +} + +template <> +int +pop_count<unsigned long long>(const unsigned long long& field) +{ + return __builtin_popcountll(field); +} + +/// Return 1 + the index of the least significant 1-bit of `field`, or zero +template <typename T> +int find_first(const T field); + +template <> +int +find_first<unsigned long>(const unsigned long field) +{ + return __builtin_ffsl(static_cast<long>(field)); +} + +template <> +int +find_first<unsigned long long>(const unsigned long long field) +{ + return __builtin_ffsll(static_cast<long long>(field)); +} + +/// Calculates the Gray Code of `value` in place +template <typename T> +std::enable_if_t<is_bitvec_v<T>> gray_code(T& value); + +/// Implementation of grayCode for any integral type +template <typename T> +std::enable_if_t<std::is_integral<T>::value> +gray_code(T& value) +{ + value ^= (value >> 1); +} + +/// Calculates the inverse Gray Code of `value` in place +template <typename T> +std::enable_if_t<is_bitvec_v<T>> gray_code_inv(T& value); + +/// Implementation of gray_code_inv for any integral type +template <typename T> +std::enable_if_t<std::is_integral<T>::value> +gray_code_inv(T& value) +{ + for (T shift = 1; shift < sizeof(T) * CHAR_BIT; shift <<= 1) { + value ^= (value >> shift); + } +} + +} // namespace detail +} // namespace chilbert + +#endif |