Trapdoors

[henry strickland]

# From cypherpunks-request at toad.com Sun Feb 21 14:14:43 1993
# 
# Does anybody have a good idea what applications this is useful for?

The old CDC CYBER machines had population count in its instruction
set.  Perhaps some scientific-type programmers would know what they
used it for.  The CYBER did not have a lot of instructions -- they
were pretty practical about what they put in.   i.e.  != VAX 

# My first thought is that it's a very quick way to do linear error 
# detection codes, since this instruction directly computes the Hamming 
# weight of a code word.

That was always my assumption.  Anyway, it's not unprecedented.

						strick
						strick at osc.versant.com