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From: gillies@p.cs.uiuc.edu
Newsgroups: comp.arch
Subject: 2 PDP-11 Instructions geeeez....
Message-ID: <76700062@p.cs.uiuc.edu>
Date: 10 Feb 89 03:47:00 GMT
Lines: 24
Nf-ID: #N:p.cs.uiuc.edu:76700062:000:887
Nf-From: p.cs.uiuc.edu!gillies    Feb  9 21:47:00 1989


In discussing the following fragment of C code --

while (*p++ = *q++);

I must have created an open problem.  E.g. "Can you code this in one
instruction?"  I said it was one instruction or a "small number".
Well, perhaps I should have said "small number" FIRST.

Thanks for all the cards & letters, but please put away your PDP-11
assembly manuals.  Apparently, it compiles into two instructions (with
both cc and pcc).


There must be an incredible number of assembly enthusiasts out there.
Would anyone like to start a monthly "puzzle posting", with topics
like "code the following subroutine fragment in 4 instructions on the
LINC-8: ....  Now do it in two's complement in 2 instructions on the
Cyber: ...."


Don Gillies, Dept. of Computer Science, University of Illinois
1304 W. Springfield, Urbana, Ill 61801      
ARPA: gillies@cs.uiuc.edu   UUCP: {uunet,harvard}!uiucdcs!gillies