> Dave Dilatush isn't the only one who uses QuickBASIC...
>
> ' Brute-force proof that the contents of two
> ' PIC registers can't be swapped (without
> ' affecting W or using a temp register) in
> ' fewer than 8 instructions.

Nice brute force approach, but you are only checking for combinations of xor
instructions- in theory shouldn't you be checking every operand on the pic
which could take a file register and f or w for the destination to make it a
complete proof?

What I was really wondering is if this could be proven mathematically as
opposed to the brute force method.
-And if it is even possible to simplyfy or optimise this type of function
using boolean algebra.

Jon Baker

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