From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me X-Spam-Level: X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00 autolearn=ham autolearn_force=no version=3.4.4 X-Google-Language: ENGLISH,ASCII-7-bit X-Google-Thread: fdb77,e782a79d4e27e773,start X-Google-Attributes: gidfdb77,public X-Google-Thread: 101deb,e782a79d4e27e773,start X-Google-Attributes: gid101deb,public X-Google-Thread: 103376,e782a79d4e27e773,start X-Google-Attributes: gid103376,public X-Google-Thread: 1073c2,e782a79d4e27e773,start X-Google-Attributes: gid1073c2,public X-Google-Thread: 10a146,e782a79d4e27e773,start X-Google-Attributes: gid10a146,public X-Google-ArrivalTime: 2001-06-28 07:28:51 PST Path: archiver1.google.com!newsfeed.google.com!newsfeed.stanford.edu!news.tele.dk!203.50.2.79!intgwlon.nntp.telstra.net!intgwpad.nntp.telstra.net!newsfeeds.bigpond.com!not-for-mail From: robin Newsgroups: comp.lang.ada,comp.lang.java.programmer,comp.lang.pl1,comp.lang.vrml,comp.lang.java.advocacy Subject: Re: S/3xx (was Market pressures for more reliable software) Message-ID: Date: Thu, 28 Jun 2001 14:14:02 GMT NNTP-Posting-Host: 144.134.49.130 X-Trace: newsfeeds.bigpond.com 993737642 144.134.49.130 (Fri, 29 Jun 2001 00:14:02 EST) NNTP-Posting-Date: Fri, 29 Jun 2001 00:14:02 EST Organization: Telstra BigPond Internet Services (http://www.bigpond.com) Xref: archiver1.google.com comp.lang.ada:9200 comp.lang.java.programmer:79379 comp.lang.pl1:1155 comp.lang.vrml:3934 comp.lang.java.advocacy:22150 Date: 2001-06-28T14:14:02+00:00 List-Id: "Shmuel (Seymour J.) Metz" writes: > > > robin wrote: > > > No. It used relative addressing, and base-relative addressing. > > (strictly speaking, it used base-displacement-indexed addressing.) > > The assembler allowed "absolute" addresses to be specified, > > which had to be filled in by the loader. > > You're confusing two different things. I'm not confusing anything. > The S/360 used absolute addresses, There was only one case when the S/3xx used absolute addressing. That was when the base register field of an instruction was zero. The displacement was then effectively the absolute address (in the range 0-4095). Remaining addressing mode was base-displacement-indexed addressing, except for SS instructions, which used base-displacement addressing. > but they were not present in > instructions. At least, it did until prefixing came along. > As to assembler language, it was relocatable addresses > that had to be adjusted by the loader; Relocatable addresses are not "adjusted by the loader". This is done automatically via the base register(s). > if the program specified > an absolute address, then the loader did not have > to adjust it. When an address constant [A(xxx)] is specified, the loader has to supply the relevant actual address. The assembler can only provide a relative address. > > Any program can be loaded anywhere in memory. > > Programs can be made dynamically relocatable, but only with some effort. > -- > Shmuel (Seymour J.) Metz