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Re: Trapdoors



> 
> > Interestingly enough, there seems to be no such instruction in the
> > VAX ...
> 
> but i believe the vax has ffs (find first set) instruction, which seems
> to have similar uses (whatever they may be).
> 
> 	peter
> 
But that's not a population count (all bits set count) instruction.
In the Motorola 68020/30/40, there's BFFFO, for Bit Field Find First One,
if anyone was curious about 'find first set' instructions.  Might as well
mention that the 386/486 have BSF and BSR, Bit Scan Forward and Reverse,
but now we're just getting into run-of-the-mill bit manipulation.