But why? The Hacker's Delight author justifies it: >Several of the variables below could be "short," but having them fullwords gives better code on gcc/Intel.

But why? The Hacker's Delight author justifies it: >Several of the variables below could be "short," but having them fullwords gives better code on gcc/Intel. But does the same happen in the "adapted" code? Does forcing 64 bit variables on a 32 bit architecture give better code? Wouldn't it have been better to just leave the compiler to choose the best appropriate size? (I guess you do that by just declaring the variable as unsigned? I'm no C guru...) Also, the fact that all of them renamed the variable un32 to un64 tells you that they didn't have the slightest idea about what they were doing :D