Path: utzoo!utgpu!water!watmath!clyde!rutgers!sri-unix!quintus!ok
From: ok@quintus.UUCP (Richard A. O'Keefe)
Newsgroups: comp.arch
Subject: Re: Brain-Clogging Decimal
Summary: 386; Burroughs
Message-ID: <459@cresswell.quintus.UUCP>
Date: 11 Dec 87 06:01:19 GMT
References: <6901@apple.UUCP> <15782@watmath.waterloo.edu> <1083@winchester.UUCP>
Organization: Quintus Computer Systems, Mountain View, CA
Lines: 17

The Intel 80386 is a pretty recent machine.
It still has instructions to support decimal arithmetic:
	AAA, AAD, AAM, AAS, DAA, DAS.
Of course this is to keep all those 8086 programs in the air...

I saw a paper years ago from somebody at Burroughs explaining some of
the decisions they had made for the B6700.  That was explicitly designed
to run Algol, Fortran, and COBOL.  It did a reasonable job of PL/I and
PASCAL as well, but didn't make a good Lisp machine.

They were very much concerned to support COBOL well.  They decided that
the best thing was to leave out decimal arithmetic entirely, but to
provide fast binary<->decimal conversion and decimal scaling.

This seems like the right decision for any machine:  even C programmers
want binary<->decimal conversion and have no objection to it being fast,
and even COBOL has USAGE COMPUTATIONAL.