Split from the original D129809.
Thank you for looking into it, @Mogball!
Basically, I wanted to test multiple folding cases in one function, so I had to make use of the ipowi in some way (so that it does not get removed completely). I made the uses by storing the results into their own cells of the array passed as a pointer to the function. I guess I can just make the function return 11 results and get rid of the store operations. Or I can also split the function into 11 functions. Please let me know which of the options you prefer.
Yes, I tried to test each line of code at least once. For some of the cases I added more than one test, e.g. for positive powers I test negative and positive base values, whereas the folding code does not care about the base sign.