Using the bit manipulation utilities

In the previous recipes, we have seen how to use std::bitset and std::vector<bool> to work with fixed and variable sequences of bits. There are, however, situations when we need to manipulate or process individual or multiple bits of an unsigned integral value. This includes operations such as counting or rotating bits. The C++20 standard provides a set of utility functions for bit manipulation as part of the numeric library. In this recipe, we will learn what they are and how to use these utilities.

Getting ready

The function templates discussed in this recipe are all available in the std namespace in the new C++20 header <bit>.

How to do it…

Use the following function templates to manipulate bits of unsigned integral types:

• If you need to perform a circular shift, use std::rotl<T>() for left rotation and std::rotr<T>() for right rotation:

  unsigned char n = 0b00111100;
  auto vl1...