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Path: utzoo!linus!philabs!cmcl2!edler
From: edler@cmcl2.UUCP (Jan Edler)
Newsgroups: net.micro.68k
Subject: Re: Call for 68K architectural change evaluations
Message-ID: <1217@cmcl2.UUCP>
Date: Wed, 15-May-85 00:08:41 EDT
Article-I.D.: cmcl2.1217
Posted: Wed May 15 00:08:41 1985
Date-Received: Thu, 16-May-85 20:27:02 EDT
References: <415@oakhill.UUCP>
Reply-To: edler@cmcl2.UUCP (Jan Edler)
Organization: New York University
Lines: 17
Summary: pdp11 allows it for position independent code

The pdp11 allows destination operands to use pc-relative addressing.
If you want position independent code, that's a good way to do it.
It isn't too useful with split I/D space, though.
How many 68000-based systems out there actually use split I/D?
It certainly seems less necessary than it is for the pdp11!

Whether or not it would be wise to make the change in a future 68000
family member is debatable.  I suspect certain applications or
environments would find it valuable, but most UNIX systems wouldn't use it.
Currently, if you need pic, I guess you have to give up an address register.
The other problem with pic on the 68000 is the lack of support for
32bit displacements, but I guess that's solved by the 68020.

	Jan Edler
	New York University
	ihnp4!cmcl2!edler
	edler@nyu.arpa