Xref: utzoo comp.arch:6438 comp.lang.c:13023 comp.lang.misc:1942 Path: utzoo!utgpu!water!watmath!clyde!att!rutgers!cbmvax!snark!eric From: eric@snark.UUCP (Eric S. Raymond) Newsgroups: comp.arch,comp.lang.c,comp.lang.misc Subject: Re: Machine-independent intermediate languages Message-ID: Date: 1 Oct 88 21:56:57 GMT References: <898@sword.bellcore.com> Organization: Network 23 AI Research Group Lines: 45 In article <898@sword.bellcore.com>, yba@arrow.UUCP (Mark Levine) writes: > You have built some questionable assumptions into your reality > check, and need to define your acronyms: Sorry, I typoed. > MLL -- is this a machine level language? That 'MLL' should have read 'MIIL'. > MIIL -- is this a machine independent intermediate language, > and if so, at what level of expressive power, and is > it any different than the MLL? How? Good question -- in fact, it's precisely the question I was trying to ask with respect to HLLs. I think more acronym confusion can be best avoided if I re-pose my three questions with this correction. They are: 1) What properties distinguish a MIIL from a HLL? (That is: how do I look at the semantics, performance, and portability of a set of languages and sort the MIILs from the HLLs?) 2) Are the portability goals for which MIILs are designed achievable at all, given the diversity of today's architectures? 3) If the answer to 2 is 'yes', *can those goals be achieved with lower complexity and cost than an HLL compiler?* The whole debate so far has been about 2). I am trying to suggest that the critical question is actually 3), that the answer to 3) appears to be 'no', and that the notion of MIIL is therefore fundamentally rather pointless, because it distracts us from the *important* questions about designing portability into HLLs. > I beleive in such a thing as a MOL, a machine oriented language, and > in a high level machine oriented language which is portable. It is > possible to do MUCH better than C. Fine. I don't so believe (I've seen too many bizarre architectures) but I have an open mind. Show me! -- Eric S. Raymond (the mad mastermind of TMN-Netnews) UUCP: ...!{uunet,att,rutgers}!snark!eric = eric@snark.UUCP Post: 22 S. Warren Avenue, Malvern, PA 19355 Phone: (215)-296-5718