What is the function parameter equivalent of constexpr?

Question

We are trying to speedup some code under Clang and Visual C++ (GCC and ICC is OK). We thought we could use constexpr to tell Clang a value is a compile tim

Answer 1

You could use non-type template arguments for this:

template <unsigned int rotate> RightRotate(unsigned int value) {
     ...
}

You'd then invoke it as

RightRotate<137>(argument); // rotate is 137 here