[jcalvinowens]

> It's not at all obvious that the overhead would be close to zero in context.

That's a fair point, although I think using a single function for all your checked addition like the one above would go a long way towards mitigating the resource waste you mention.

Maybe that's a naive assumption on my part: I suppose you could construct a branch predictor that maintains state based on the function call chain as opposed simply using the address of the branch... but that seems like it would be prohibitively complex.