Re: Bitmanipulation in Ada

[Jean-Pierre Rosen <rosen@adalog.fr>]

Bernd Specht a écrit :

> Always? What do you think about bitscrambling software which has to treat 
> data alternating as bitvector and as integer value in a loop like this (not 
> exeactly this for securitity reasons):
> 
> ...
> loop
>   declare
>     x : boolean;
>   begin
>      x := b(k);
>      b(k) := b(32 - k);
>      b (32 - k) := x;
>      I := I * prime1 mod prime2;
>   end;
> end loop;
> 

Such software does not use signed integers, but modular integers. And 
you have all the bit operations you need on modular integers.
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            J-P. Rosen (rosen@adalog.fr)
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