From mboxrd@z Thu Jan  1 00:00:00 1970
From: jnc@mercury.lcs.mit.edu (Noel Chiappa)
Date: Sun, 18 Mar 2018 09:33:39 -0400 (EDT)
Subject: [TUHS] RIP John Backus
Message-ID: <20180318133339.794D318C08E@mercury.lcs.mit.edu>

    > From: Paul McJones <paul at mcjones.org>

    > I suspect the CPU architect (Gene Amdahl -- not exactly a dullard)
    > intended programmers store array elements at increasing memory
    > addresses, and reference an array element relative to the address of the
    > last element plus one. This would allow a single index register (and
    > there were only three) to be used as the index and the (decreasing)
    > count.

I suspect the younger members of the list, who've only ever lived in a world
in which one lights ones cigars with mega-gates, so to speak, may be missing
the implication here.

Back when the 704 (a _tube_ machine) was built, a register meant a whole row
of tubes. That's why early machines had few/one register(s).

So being able to double up on what a register did like this was _HYYUUGE_.

       Noel