Position of least significant bit that is set

Question

I am looking for an efficient way to determine the position of the least significant bit that is set in an integer, e.g. for 0x0FF0 it would be 4.

A trivial impleme

Answer 1

If C++11 is available for you, a compiler sometimes can do the task for you :)

constexpr std::uint64_t lssb(const std::uint64_t value)
{
    return !value ? 0 : (value % 2 ? 1 : lssb(value >> 1) + 1);
}

Result is 1-based index.