Warp  wrote in message <44f2271e@news.povray.org>:
>   I don't know if this makes a difference in speed in different processors,
> but it *might* be that the AMD64 can smartly perform those operations
> (which always yield '0' as the answer) faster with its 64-bit-mode
> enhancements. But not necessarily. It's just a guess.

No, it does not chance anything at all.

I made that benchmark in the first time to compare floating point arithmetic
and 64 bits integer arithmetic, to select which one to use for a situation
where both would be acceptable. At first, I just used "r += i * i", but I
added the division to get a result that fits in 64 bits, and to be able to
compare it to a trusted result. Adding it barely changed the timings at all.

>   The 'register' keyword is a no-op. It doesn't do anything and is just
> a useless backwards-compatible drag of history.

I tried it because I suspected the 80 bits / 64 bits problem: maybe gcc
would feel freer to keep the double in 80 bits precision. But it did not
change anything.

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