> That introduces lots of branching in the code which is busy-loop-based and branch prediction is not what I'd want for consistent timing. I don't see how so b

> That introduces lots of branching in the code which is busy-loop-based and branch prediction is not what I'd want for consistent timing. I don't see how so basic a call would create conditional branches that would have to be predicted. Calling the function is an unconditional branch-and-link, after which it should just be doing a load and returning. (It's LLVM with the equivalent of -O2, it's not going to be doing anything weird.) Unless the return address isn't cached in these processors?