C++ function parameters: use a reference or a pointer (and then dereference)?

Question

I was given some code in which some of the parameters are pointers, and then the pointers are dereferenced to provide values. I was concerned that the pointer dereferencing would cost cycles, but after looking at a previous StackOverflow article: How expensive is it to dereference a pointer?, perhaps it doesn't matter.

Here are some examples:

bool MyFunc1(int * val1, int * val2)
{
    *val1 = 5;
    *val2 = 10;
    return true;
}

bool MyFunc2(int &val1, int &val2)
{
    val1 = 5;
    val2 = 10;
    return true;
}

I personally prefer the pass-by-reference as a matter of style, but is one version better (in terms of process cycles) than another?

Answer 1

My rule of thumb is to pass by pointer if the parameter can be NULL, ie optional in the cases above, and reference if the parameter should never be NULL.