bit

Utility functions for manipulating binary numbers.
A reverse engineered version of C++20’s and C++23’s <bit> header.

bit_cast

template <typename TDestination, typename TSource>
ETL_CONSTEXPR14 TDestination bit_cast(const TSource& source) ETL_NOEXCEPT

Description
Returns a value of type TDestination by reinterpreting the TSource object.

byteswap

template <typename T>
ETL_CONSTEXPR14 T byteswap(T n) ETL_NOEXCEPT

Description
Reverses the bytes in n.

has_single_bit

template <typename T>
ETL_CONSTEXPR14 bool has_single_bit(T n) ETL_NOEXCEPT

Description
Checks if n is a power of two, or has one bit set.

bit_ceil

template <typename T>
ETL_CONSTEXPR14 T bit_ceil(T n)

Description
Calculates the smallest power of two, that is not smaller than n.

bit_floor

template <typename T>
ETL_CONSTEXPR14 T bit_floor(T n) ETL_NOEXCEPT

Description
Calculates the largest power of two that is not greater than n.

bit_width

template <typename T>
ETL_CONSTEXPR14 T bit_width(T n) ETL_NOEXCEPT

Description
If n is not 0, calculates the number of bits needed to store it.
If n is 0, then the result is 0.

rotl

template <typename T>
ETL_NODISCARD ETL_CONSTEXPR14 T rotl(T value, int n) ETL_NOEXCEPT

Description
Computes a left circular shift of value by n.

rotr

template <typename T>
ETL_NODISCARD ETL_CONSTEXPR14 T rotr(T value, int n) ETL_NOEXCEPT

Description
Computes a right circular shift of value by n.

countl_zero

template <typename T>
ETL_NODISCARD ETL_CONSTEXPR14 int countl_zero(T value) ETL_NOEXCEPT

Description
Returns the number of consecutive 0 bits in n, starting from the most significant bit (left).

countl_one

template <typename T>
ETL_NODISCARD ETL_CONSTEXPR14 int countl_one(T value) ETL_NOEXCEPT

Description
Returns the number of consecutive 1 bits in n, starting from the most significant bit (left).

countr_zero

template <typename T>
ETL_NODISCARD ETL_CONSTEXPR14 int countr_zero(T value) ETL_NOEXCEPT

Description
Returns the number of consecutive 0 bits in n, starting from the least significant bit (right).

countr_one

template <typename T>
ETL_NODISCARD ETL_CONSTEXPR14 int countr_one(T value) ETL_NOEXCEPT

Description
Returns the number of consecutive 1 bits in n, starting from the least significant bit (right).

popcount

template <typename T>
ETL_NODISCARD ETL_CONSTEXPR14 int popcount(T value) ETL_NOEXCEPT

Description
Counts the number of 1 bits in an unsigned integer.