Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Path: utzoo!watmath!clyde!rutgers!sri-unix!hplabs!felix!jim
From: jim@felix.UUCP
Newsgroups: comp.arch
Subject: Stack Growth Direction
Message-ID: <2249@felix.UUCP>
Date: Mon, 9-Feb-87 12:27:36 EST
Article-I.D.: felix.2249
Posted: Mon Feb  9 12:27:36 1987
Date-Received: Tue, 10-Feb-87 07:11:57 EST
Sender: root@felix.UUCP
Reply-To: jim@felix.UUCP (Jim Gilbert)
Distribution: world
Organization: FileNet Corp., Costa Mesa, CA
Lines: 36


Although stacks do grow down on:

	DEC PDP-11
	DEC VAX-11
	Zilog Z-80
	Zilog Z-8000
	Intel 8080, 8085
	MOS Technology 6502
	Motorola 6800
	Motorola 68000
	NSC 320xx

they do grow up on some machines

	Burroughs B-5x00
	Burroughs B-6x00
	Burroughs B-7x00
	Basic/Four 8000

and some machines do not include any particular support for 
either direction

	IBM S/360


Having done a great deal of compiler and system code for the Basic/Four 8000
I found no particular disadvantage in having the stack grow up, in fact,
on this thoroughly big-endian machine, it was most pleasant to have "up"
mean "towards higher addresses".  It also made the microcode/hardware
for checking segment overflows simpler since everything only grew
at the higher-addressed end.

Jim Gilbert
FileNet Corporation
...hplabs!felix!jim