>> - Commodore 64 (6510 @ ~1 MHz)
> 
> Most instructions took from 2 to 5 clock cycles, so I'd venture to say 
> that the 6510 ran between .2 and .5 MIPS.  Floating point is implemented 
> in software, and since the processor didn't have a hardware multiply 
> (and shifts were one bit at a time), it probably took dozens of machine 
> cycles for addition/subtraction and hundreds for multiplication and 
> division.  I doubt that it ever got much past ten kiloflops, and 
> probably averaged lower than that.

I recall there was no multiplication or division (in fact, I have the 
listing somewhere for a program that does repeated addition to achieve 
multiplication), but I'd forgotten about the lack of arbitrary bit 
shifts. (Not that it would matter for integer multiplication...)

Yes, definitely hundreds of instructions for floating-point arithmetic!

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