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Re: Pentium bug and CRYPTO




Dave Horsfall writes:
 > I'd be horrified if a crypto implementation used floating point, with
 > the implied imprecision...

The imprecision in floating point is a factor only if you choose to
pay attention to it.  It is possible to use floating point all day
long to do what are essentially integer calculations.  indeed, there
have been CPUs (the CDC 6000 series come to mind) that have no integer
multiply or divide instruction.  Instead, one used the floating point
instructions and then extracted the result (carefully) from the
mantissa.

Floating point isn't magic, it's just microcode.  (Well, not in the
CDC 6000 I guess...)

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