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Re: fast 386 DES code figures
Steve & Phil,
When four us did an implementation back in the late 70s, as
grad students at MIT, we used tables to compose SP and E. Later one
of the grad students figured out how to E in a very efficient fashion,
whic allowed us to go back to just an S&P composition, with 32-bit
vs. 48 bit values. I think that's the common approach today, with
the asusmption that the space devoted to the tables is not a big deal
on most modern machines. Our fastest implementations were in line code,
but instruction cacheing may argue for loops.
Steve
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