Path: utzoo!utgpu!jarvis.csri.toronto.edu!cs.utexas.edu!usc!snorkelwacker!apple!Apple.COM!lsr
From: lsr@Apple.COM (Larry Rosenstein)
Newsgroups: comp.sys.mac.hardware
Subject: Re: Why no VM on a 68K? (was: Re: Why 68000?)
Message-ID: <6956@internal.Apple.COM>
Date: 28 Feb 90 18:23:58 GMT
Sender: usenet@Apple.COM
Organization: Objects-R-Us,  Apple Computer, Inc.
Lines: 18
References:<1990Feb11.154304.19943@smsc.sony.com> <3919@hub.UUCP> <10223@hoptoad.uucp> <1990Feb15.155556.5319@uncecs.edu> <19472@dartvax.Dartmouth.EDU> <1672@aurora.AthabascaU.CA>

In article <1672@aurora.AthabascaU.CA> rwa@cs.AthabascaU.CA (Ross 
Alexander) writes:
> A trick you can use in a 7th edition environment to _fake_ growable
> stack segs it to insert a "tst -nnn(sp)" where nnn is the size of the
> stack frame for the function being entered as the first instruction of

This Lisa did this.  It also allowed for demand swapping of code segments. 
 This was done by figuring out how to restart certain JMP and JSR 
instructions and making sure that these were the only instructions used 
for cross-segment references.  Since youcan restrict how data segments 
were accessed, data segments were loaded and unloaded under programmer 
control.

Larry Rosenstein, Apple Computer, Inc.
Object Specialist

Internet: lsr@Apple.com   UUCP: {nsc, sun}!apple!lsr
AppleLink: Rosenstein1