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=-0.8 required=5.0 tests=BAYES_00,INVALID_MSGID, SUBJ_ALL_CAPS autolearn=no autolearn_force=no version=3.4.4 X-Google-Language: ENGLISH,ASCII-7-bit X-Google-Thread: 103376,9e20292f693f1408 X-Google-Attributes: gid103376,public From: dewar@merv.cs.nyu.edu (Robert Dewar) Subject: Re: ADA CORE TECHNOLOGIES ANNOUNCES GNAT-TO-JAVA SYSTEM Date: 1997/09/18 Message-ID: #1/1 X-Deja-AN: 273649549 References: <34196E8E.1790@gsfc.nasa.gov> <341B2309.4A41@ibm.net> <34204085.5377@ibm.net> Organization: New York University Newsgroups: comp.lang.ada Date: 1997-09-18T00:00:00+00:00 List-Id: Ralph replies to Paul: <<> I realize that the JVM port is motivated (quite rightly, IMO) by economic > reasons, but I wonder if some other "intermediate form" besides byte > codes might be better if one wanted a portable format which could then > be compiled. > > -- Brian There already one such thing. It's called slim binaries and is used on some Oberon-2 system. These system use some sort of abstract tree representation as "byte-code". This AST is then compiled on the fly on the supported platform. >>From what I read on it the technology gives you protable object-code and native peformance. Also the program flow analysis which is done in Java>> Oh goodness, this is an OLD OLD idea, P-code is of course one of the earliest and best known attempts (there was a whole technology of native code generators, and no doubt you could find a SMS sales person willing to make the same absurd claim of 100% portability with native performance that is always bandied about for such systems. But there are literally dozens of designs and attempts in this direction, it is after all a perfectly obvious idea, closely related to the ancient UNCOL proposal. For a slightly more credible attempt, see the DDCI technical product information, which describes how they use one of the more sophisticated approaches along these lines. If DDCI is listening, I will let them fill in the details!