Warp <war### [at] tagpovrayorg> wrote:
>
>   A 64-bit processor has 64-bit registers. That's about it. All the
> opcodes are still the same (well, mostly).
>
>   I don't know what you think a 64-bit processor is, but it's basically
> the exact same thing as a 32-bit processor with the only difference that
> registers are 64-bit long instead of 32-bit.
>
>   What does it mean that they are twice as long? It means that you can
> make integer calculations with twice as many bits and also that you can
> directly access a whole lot more of memory. How this could speed up
> anything is beyond me.
>

>                                                           - Warp

I wasn't arguing that the 64-bit processors should be twice as fast.  The
answer to that question is clearly no.  I was trying to explain why
reasonably intelligent people might ask the question.  It's because some
integer operations may be doubled up using the extra registry space.  As
you've pointed out, due to all the bit shifting and underflow/overflow
error detection, there is clearly no speed increase, and very few
operations could actually benefit from this approach anyway.  However, I
think it was an excellent question to ask, and the resulting discussion
here has been enlightening.  Hopefully we've all learned a lot more about
how 64-bit computing works, which was the intent to begin with.  Thanks for
your contribution to the discussion (no sarcasm here).

Mike

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