std::floor2

 

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Defined in header <bit>
template< class T > constexpr T floor2(T x) noexcept;		(since C++20)

If x is not zero, calculates the largest integral power of two that is not greater than x. If x is zero, returns zero.

This overload only participates in overload resolution if T is an unsigned integer type (that is, unsigned char, unsigned short, unsigned int, unsigned long, unsigned long long, or an extended unsigned integer type).

Return value

Zero if x is zero; otherwise, the largest integral power of two that is not greater than x.