I guess the question is whether the compiler should optimize a function containing a loop for a single null terminator, or for more data.

I would suggest the latter is what you want most of the time.

There's also the option of running a quick check for the null terminator before the loop, and then optimizing the loop for the other options.

But in any case, I think the demonstration of the technique of rearranging branches is interesting, and I needed a program to apply it to.