This program was designed, to do nothing. It's intention, was to check compiler optimisation. Having times from the Cray 1, CDC 7600, and about every computer in existence, at the time, just served to confuse the issue. It's hard convince someone that an Interdata 8/32, is faster than a Cray 1. For that programme, it was.
Programmers of that generation, had a sense of hummer.