Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!zaphod.mps.ohio-state.edu!sdd.hp.com!spool.mu.edu!news.nd.edu!mentor.cc.purdue.edu!pop.stat.purdue.edu!hrubin From: hrubin@pop.stat.purdue.edu (Herman Rubin) Newsgroups: comp.arch Subject: Re: Compilers, architecture, and efficiency Message-ID: <11713@mentor.cc.purdue.edu> Date: 1 May 91 18:40:16 GMT Article-I.D.: mentor.11713 References: <1991Apr28.154603.8003@rice.edu> <1991Apr29.155945.29907@rice.edu> <41279@genrad.UUCP> Sender: news@mentor.cc.purdue.edu Lines: 51 In article <41279@genrad.UUCP>, jkw@genrad.com (J. Kyle Wilson) writes: > In article <11609@mentor.cc.purdue.edu> hrubin@pop.stat.purdue.edu (Herman Rubin) writes: > >In article <1991Apr30.025904.13028@rice.edu>, preston@ariel.rice.edu (Preston Briggs) writes: > >> hrubin@pop.stat.purdue.edu (Herman Rubin) writes: > >> >What is needed for the user to be able to communicate what operations are > >> >wanted. > >> I agree that the user should be able to instruction the computer. > >> However, I don't think I want to specify the assembly operations. > >> Instead, I want to manipulate numbers, sets, sequences, and objects in a > >> somewhat high-level fashion. Then I want the compiler to make very good > >> code out of my specification. > >But what if I find Boolean operations useful in dealing with floats, which > >I do for certain purposes? There are other operations which I can use for > >useful purposes, but only if they are fast. You do not know these operations, > >and the language community has seen fit to ignore what those who are capable > >of versatility can envision. > The language community has been providing the greatest good for the > greatest number where possible. If you have need of an optimization > that no one has seen fit to add to a compiler you are using your best > bet may be to hire a compiler writer to tweak it to handle that case. ....................... > Satisfying your requests would require the compiler to recognize a > large number of special cases each of which would likely be used by a > small segment of the user community, while requiring si ........................... Satisfysing my requests would require nothing of the sort. I see no reason why I should have to hire a compiler writer for each augmentation. I am asking the compiler writers and language designers to do what is normally done in other fields; do not freeze the language, and allow the user to augment it with convenient notation. Essentially this means that the user can put translations of his method of code into HLL or machine instructions, or even into other espressions. In some cases, even alternate translations should be giver, and the optimizer decide, again using user- supplied information. An optimal route to travel does not have to be restricted to major highways. Using lesser highways or even city streets may be more efficient. The route could also be dependent on the time of day and the type of vehicle. Do not deprive the driver of the gas pedal and the steering wheel. -- Herman Rubin, Dept. of Statistics, Purdue Univ., West Lafayette IN47907-1399 Phone: (317)494-6054 hrubin@l.cc.purdue.edu (Internet, bitnet) {purdue,pur-ee}!l.cc!hrubin(UUCP)