Stefan, Yes, in special cases you can outperform C.
I don't claim that it might not be possible with better compiler technology to outperform C. I'm keeping my eye on D because it promises to be one of those languages. But the truth of the matter, despite the promises, C is the best performing compiler right now. I would feel silly trying to sit here and convince you of this if you don't already know it. Look at any objective benchmark. Fortran does outperform C in some code and is no slouch in general - but it's still going to be slower than C in most things such as Chess and Go programs. - Don Stefan Nobis wrote: > Don Dailey <[EMAIL PROTECTED]> writes: > > >> I thinks it's very difficult to outperform C since C really is just >> about at the level of assembly language. >> > > No, in special cases it's not that hard to outperform C, because the > language spec dictates some not so efficient details. C has an ABI and > it's specification is optimized for the general case. Nearly every > design decision has advantages and disadvantages. So if you look at > the spec it's clearly possible to construct cases that are > exceptionally bad for this specific spec. If you have a language > without these restriction it's quite possible to get better results in > this constructed case. > > So yes, it may be difficult and maybe most or even all cases in which > it's possible to outperform C with Lisp are unimportant for any > practical purposes, but nevertheless it's possible. > > And by the way I don't think C is really the best language for maximum > performance. Just think about Fortran. AFAIK in it's main domain it > easily outperforms C. There are also languages like OCAML, Ada, Forth > and quite some others with really capable compilers und language specs > that leave more freedom to compiler writers and such leave more room > for different kind of optimizations. > > So the claim that C is the single one high level language with which > you can get the maximum performance is quite an urban legend and > completly unjustified. > > >> I think the right approach to a language faster than C is to simply >> write a better C that is specifically designed to have more >> opportunities for optimization. >> > > C is a really crappy language, especially from the performace point of > view. It's so low level that you are able to get really good > performance despite all the odds of the language. You have to program > around all the performace pitfalls, you have to do all performance > optimizations yourself. C is no help here. So why should C be a good > starting point for a language striving to make high performance > computing easy? > > BTW: No, Lisp is also not a very good starting point for this special > goal, but I would say Lisp would make a much better start than C, > because Lisp shows you how much a good language and compiler can easy > the pain for the developer while in C he is all alone. > > >> I really don't think a truly higher level language will ever beat C >> or a performance improved C. >> > > Have you really any hints, done any scientific benchmarks with > languages like OCAML, Oz, Forth, Fortran, Ada, Scheme, and many others > to make your claim any more than pure guesswork? > > >> There is some hope that a JIT can do some optimizations not possible >> with a static compiler - but even if this is the case C could follow >> this path too. >> > > It's not easy and maybe not even possible for C to follow this route > because C code (source and object) don't have very much > information. Higher level languages provide much more information > about what's going on, what data is in the game and the like. Or they > set much more restrictions (like restrictive type systems). All these > additional informations and/or restrictions make some algorithms > for inference tractrable or even fast. Without these you are lost. So > no, there are no hints that C would ever get such optimizations. > > > ------------------------------------------------------------------------ > > _______________________________________________ > computer-go mailing list > computer-go@computer-go.org > http://www.computer-go.org/mailman/listinfo/computer-go/ _______________________________________________ computer-go mailing list computer-go@computer-go.org http://www.computer-go.org/mailman/listinfo/computer-go/
