Benchmarking the SGI: Floating point faster than integer?

[Bron Campbell Nelson]

In article <1464 at ruunsa.fys.ruu.nl>, chooft at ruunsa.fys.ruu.nl (Rob Hooft) writes:
> As I am planning to buy a PC, I am benchmarking all computers available to
> me. On our PI this resulted in a 'pleasant' surprise: Floating point
> multiplications are about twice as fast as integer multiplications. Is there
> anybody that can explain the results of the following session to me?
[session deleted]

The explaination  is simple: on the MIPS R2000 and R3000 cpus, floating
point multiplication *IS* about twice as fast as integer multiplication
(actually, a bit more than twice as fast).  The ratio for division is
even greater.

My understanding is that MIPS decided to throw a lot of silicon at the
floating point problem, while they found that the majority of integer
multiplies in "real" programs involved a constant term, and so could be
done with shifts and adds.  Thus, less silicon was thrown at the integer
multiply problem (and even less at the integer divide).

--
Bron Campbell Nelson
bron at sgi.com  or possibly  ..!ames!sgi!bron
These statements are my own, not those of Silicon Graphics.