Re: Hashing on System.Address

[Marius Amado Alves <amado.alves@netcabo.pt>]

> ... The other thing I haven't really figured out is what to do
> if you have a 64-bit address, and Hash_Type is only 32...

I gave a general solution to this class of cases before:

<<
Treat both the input and output values as bit strings X (1 .. M) and Y 
(1 .. N) respectively. (Use representation clauses, packed arrays, and 
unchecked conversion for this.) Make N small, say 16. Set Y bits to the 
value of X bits as follows:

if M > N, Y (J) = X (1 + (J - 1) * M / N), for J in 1 .. N

if M = N, Y = X

if M < N, initialize Y to all zeros,
  then let Y (1 + (I - 1) * N / M) = X (I), for I in 1 .. M
 >>