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=-1.3 required=5.0 tests=BAYES_00,INVALID_MSGID autolearn=no autolearn_force=no version=3.4.4 X-Google-Language: ENGLISH,ASCII-7-bit X-Google-Thread: 103376,99a6311c4195e21b X-Google-Attributes: gid103376,public X-Google-Thread: 1094ba,99a6311c4195e21b X-Google-Attributes: gid1094ba,public From: Dieter Britz Subject: Re: Matrix Multiplication Date: 1999/12/16 Message-ID: #1/1 X-Deja-AN: 561331016 References: <385699B5.59C14D03@lmco.com> <01bf4708$99ef98f0$022a6282@dieppe> Content-Type: TEXT/PLAIN; charset=US-ASCII X-Complaints-To: news@daimi.au.dk X-Trace: xinwen.daimi.au.dk 945331864 10434650 255.255.255.255 (16 Dec 1999 08:11:04 GMT) Organization: University of Aarhus, Department of Computer Science (DAIMI) Mime-Version: 1.0 NNTP-Posting-Date: 16 Dec 1999 08:11:04 GMT Newsgroups: comp.lang.ada,comp.lang.fortran Date: 1999-12-16T08:11:04+00:00 List-Id: On Wed, 15 Dec 1999, Robert A Duff wrote: > "Pascal Obry" writes: > > > Well I don't know what is a fast or slow language !! > > I do. A fast language is one for which it is feasible to build > compilers that generate fast code. A slow language is one for which > that is not feasible. > > Also I prefer to put the burden of proof on the language advocates -- > that is, a language should be considered "slow" until proven "fast" by > the existence of at least one good production-quality compiler. > > By this definition, Smalltalk, for example, is slow -- I've never seen a > Smalltalk compiler that can generate fast code. Furthermore, it seems > impossible, without doing all code generation at link time, which I > claim is not feasible in many cases. > > I don't know whether Fortran is faster than Ada at matrix multiplies, > but it does seem like a meaningful question to ask. If you measured > lots of compilers, you could learn something useful. This must depend on the specific compiler. These have become better at optimising code the last couple of decades. Years ago, I often needed to shift large array sections, and (on a PDP11, under RT11) wrote myself an assembler-code subroutine to do the shift; that turned out to run about 100 times as fast as the equivalent Fortran code. I feel sure that now, there would not be so much difference, if any (but I don't have an assembler anymore). Later, I compared Pascal and Fortran 77 on a VAX machine, and Fortran was, on average, about twice as fast. It might depend on what sort of operations you normally program. -- Dieter Britz alias db@kemi.aau.dk; http://www.kemi.aau.dk/~db *** Echelon, bomb, sneakers, GRU: swamp the snoops with trivia! ***