Path: utzoo!mnetor!uunet!steinmetz!davidsen From: davidsen@steinmetz.ge.com (William E. Davidsen Jr) Newsgroups: comp.arch Subject: Re: negative addresses Message-ID: <10769@steinmetz.ge.com> Date: 10 May 88 14:17:39 GMT References: <2393@uvacs.CS.VIRGINIA.EDU> Reply-To: davidsen@crdos1.UUCP (bill davidsen) Organization: General Electric CRD, Schenectady, NY Lines: 22 In article <2393@uvacs.CS.VIRGINIA.EDU> wulf@uvacs.CS.VIRGINIA.EDU (Bill Wulf) writes: | Has anyone ever seen a machine with "negative addresses", that is, one | where the address space is -2**31..2**31-1 rather than 0..2*32-1?? | Any thoughts on what the problems with such a scheme might be (or are)? "bits is bits," but I suspect that a lot of programs will have trouble with non-contiguous addressing. Address wrap forces the lowest address to "follow" the highest address, which may make io interesting. | | Why ask such a question, you ask -- well, I'm trying to remove unsigned | arithmetic from WM, and as far as I can tell, the primary (only?) use | of unsigned arithmetic is for address computations. Soooooo... My gut feeling is that this is not correct, but I have no metrics at this time to confirm or deny what you say. | | Bill Wulf -- bill davidsen (wedu@ge-crd.arpa) {uunet | philabs | seismo}!steinmetz!crdos1!davidsen "Stupidity, like virtue, is its own reward" -me