Re: "C Is The Greenest Programming Language" by: Chris Lott

From	Bart <bc@freeuk.com>
Newsgroups	comp.lang.c, comp.lang.c++
Subject	Re: "C Is The Greenest Programming Language" by: Chris Lott
Date	2021-12-11 18:46 +0000
Organization	A noiseless patient Spider
Message-ID	<sp2rm0$kls$1@dont-email.me> (permalink)
References	(1 earlier) <snivri$15p1$1@gioia.aioe.org> <snl5oc$8vo$1@solani.org> <snm6l8$r4e$1@solani.org> <snm835$1bb$1@dont-email.me> <sp2bb2$5c1$1@z-news.wcss.wroc.pl>

Cross-posted to 2 groups.

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On 11/12/2021 14:07, antispam@math.uni.wroc.pl wrote:
> In comp.lang.c Bart <bc@freeuk.com> wrote:
>>
>> (Also, how did Lisp manage to be only 3 times as slow as C? It was both
>> interpreted /and/ dynamically typed last I looked.)
> 
> Lisp may be compiled to machine code and when speed is important
> you will choose implementation with good compiler.  Concerning
> "dynamically typed": Lisp has type declarations which are
> optional.  Without declarations your types can be anything so
> you get true dynamic typing.  With declarations you can declare
> that your variable contains machine integers or doubles and
> good Lisp compiler will generate directly machine code.
> 
> It is debatable how much C features contribute to speed of
> resulting machine code.  In Lisp each data structure has
> identifying header and you get efficient code only for arrays
> of "primitive types", there is no way in Lisp to get something
> with memory layout of C array of structs.  So in principle
> in C you may have more compact data structures that keep
> related items together, which leads to better cache use
> and consequently less time spent on memory accesses.
> When it comes to computations, it is mostly matter of
> effort spent on compiler.  There was enormous effort spent
> on C compilers and compilers like gcc are hard to beat.
> Still, it depends on specific code: for simple code with
> memory accesses that hit cache using Lisp I usually get about
> half of speed of gcc-compiled C.  More tricky cases may be
> somewhat slower.  For example I noted that Lisp compiler that
> I use will use multiplication when sequentlially accessing
> row of two dimensional array in a loop.  This lead to machine
> code that is 4-5 times slower than code generated by gcc.
> When code is memory-intensive (say pointer chaising) speed
> is essentially indepenent of language (of course assuming
> that language can express reasonanably efficient pattern
> of memory accesses).
> 
> Looking at generated machine code I would expect that Lisp
> will give me better or equal runtime speed compared to
> your C compiler.

To me the most apt description of Lisp seems to be 'shape-shifting'.

The language is dynamically typed when it suits, but can switch to 
static typed when someone complains of the speed (but it needs someone 
to revise the program).

It also can be run-from-source, or it can compile to some interpreted 
internal form, or to native code (or, I guess, use some sort of JIT).

It also seems to be capable of anything; don't like how it does 
assignment; there several other ways it can pull out of the hat. That 
loop not powerful enough, there are half a dozen other forms with any 
number of parameters.

You just can't pin it down. And therefore it seems immune to any 
criticism; there is always a way to change it.

> As little anecdote, I wrote code compiled via Lisp compiler
> that was intended to be speed competivive with code in
> interpreted language calling to optimized C libraries to
> do main work.  AFAIK my code was faster, mainly because
> I was able to create combined operation which saved essentally
> half work compared to separate library calls.  That was
> enough to compensate better code generator from C compiler.
> Of course, coding my routine in C I would have both gain
> form combined operation and gain from better compiler
> optimization.  OTOH affected routines were about 60 lines
> of code, while the whole thing was about 6000 lines.
> Writing all in C would take _much_ more effort and the
> result would be less useful as my routines were integrated
> into existing program (which would be harder to do with
> C code).

I always reckoned that the right balance of dynamic code plus static 
code, should not be more than 1-2 times as slow as 100% static (save for 
programs with short runtimes)

And, sometimes, as you found, it can be a bit faster!

Thread

"C Is The Greenest Programming Language" by: Chris Lott Lynn McGuire <lynnmcguire5@gmail.com> - 2021-11-22 16:19 -0600
  Re: "C Is The Greenest Programming Language" by: Chris Lott "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2021-11-22 14:58 -0800
    Re: "C Is The Greenest Programming Language" by: Chris Lott Juha Nieminen <nospam@thanks.invalid> - 2021-11-23 07:10 +0000
      Re: "C Is The Greenest Programming Language" by: Chris Lott "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2021-11-23 13:12 -0800
        Re: "C Is The Greenest Programming Language" by: Chris Lott Juha Nieminen <nospam@thanks.invalid> - 2021-11-24 10:54 +0000
          Re: "C Is The Greenest Programming Language" by: Chris Lott Philipp Klaus Krause <pkk@spth.de> - 2021-11-24 12:01 +0100
            Re: "C Is The Greenest Programming Language" by: Chris Lott David Brown <david.brown@hesbynett.no> - 2021-11-24 13:58 +0100
      Re: "C Is The Greenest Programming Language" by: Chris Lott "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2021-11-23 13:23 -0800
  Re: "C Is The Greenest Programming Language" by: Chris Lott Richard Damon <Richard@Damon-Family.org> - 2021-11-22 18:25 -0500
    Re: "C Is The Greenest Programming Language" by: Chris Lott Juha Nieminen <nospam@thanks.invalid> - 2021-11-23 07:21 +0000
      Re: "C Is The Greenest Programming Language" by: Chris Lott Thiago Adams <thiago.adams@gmail.com> - 2021-11-23 04:50 -0800
      Re: "C Is The Greenest Programming Language" by: Chris Lott Guillaume <message@bottle.org> - 2021-11-23 17:56 +0100
        Re: "C Is The Greenest Programming Language" by: Chris Lott Juha Nieminen <nospam@thanks.invalid> - 2021-11-24 10:55 +0000
      Re: "C Is The Greenest Programming Language" by: Chris Lott Lynn McGuire <lynnmcguire5@gmail.com> - 2021-11-23 19:00 -0600
        Re: "C Is The Greenest Programming Language" by: Chris Lott scott@slp53.sl.home (Scott Lurndal) - 2021-11-24 16:04 +0000
    Re: "C Is The Greenest Programming Language" by: Chris Lott Philipp Klaus Krause <pkk@spth.de> - 2021-11-24 11:43 +0100
  Re: "C Is The Greenest Programming Language" by: Chris Lott om@iki.fi (Otto J. Makela) - 2021-11-23 14:17 +0200
    Re: "C Is The Greenest Programming Language" by: Chris Lott DozingDog@thekennel.co - 2021-11-23 16:53 +0000
      Re: "C Is The Greenest Programming Language" by: Chris Lott om@iki.fi (Otto J. Makela) - 2021-11-24 11:40 +0200
        Re: "C Is The Greenest Programming Language" by: Chris Lott DozingDog@thekennel.co - 2021-11-24 15:49 +0000
    Re: "C Is The Greenest Programming Language" by: Chris Lott Lynn McGuire <lynnmcguire5@gmail.com> - 2021-11-23 19:01 -0600
      Re: "C Is The Greenest Programming Language" by: Chris Lott om@iki.fi (Otto J. Makela) - 2021-11-24 11:33 +0200
        Re: "C Is The Greenest Programming Language" by: Chris Lott Lynn McGuire <lynnmcguire5@gmail.com> - 2021-11-24 15:28 -0600
  Re: "C Is The Greenest Programming Language" by: Chris Lott Bonita Montero <Bonita.Montero@gmail.com> - 2021-11-23 14:39 +0100
    Re: "C Is The Greenest Programming Language" by: Chris Lott DozingDog@thekennel.co - 2021-11-23 16:55 +0000
      Re: "C Is The Greenest Programming Language" by: Chris Lott Richard Damon <Richard@Damon-Family.org> - 2021-11-23 12:28 -0500
        Re: "C Is The Greenest Programming Language" by: Chris Lott Bonita Montero <Bonita.Montero@gmail.com> - 2021-11-23 19:05 +0100
          Re: "C Is The Greenest Programming Language" by: Chris Lott Richard Damon <Richard@Damon-Family.org> - 2021-11-23 13:41 -0500
            Re: "C Is The Greenest Programming Language" by: Chris Lott Bonita Montero <Bonita.Montero@gmail.com> - 2021-11-23 19:53 +0100
              Re: "C Is The Greenest Programming Language" by: Chris Lott Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2021-11-23 16:31 -0800
              Re: "C Is The Greenest Programming Language" by: Chris Lott Richard Damon <Richard@Damon-Family.org> - 2021-11-23 21:27 -0500
                Re: "C Is The Greenest Programming Language" by: Chris Lott Bonita Montero <Bonita.Montero@gmail.com> - 2021-11-24 18:32 +0100
                Re: "C Is The Greenest Programming Language" by: Chris Lott Richard Damon <Richard@Damon-Family.org> - 2021-11-24 12:54 -0500
                Re: "C Is The Greenest Programming Language" by: Chris Lott Bonita Montero <Bonita.Montero@gmail.com> - 2021-11-24 20:52 +0100
                Re: "C Is The Greenest Programming Language" by: Chris Lott Richard Damon <Richard@Damon-Family.org> - 2021-11-24 15:13 -0500
                Re: "C Is The Greenest Programming Language" by: Chris Lott Bonita Montero <Bonita.Montero@gmail.com> - 2021-11-25 19:13 +0100
          Re: "C Is The Greenest Programming Language" by: Chris Lott Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2021-11-23 16:25 -0800
        Re: "C Is The Greenest Programming Language" by: Chris Lott DozingDog@thekennel.co - 2021-11-24 15:48 +0000
          Re: "C Is The Greenest Programming Language" by: Chris Lott Richard Damon <Richard@Damon-Family.org> - 2021-11-24 11:54 -0500
            Re: "C Is The Greenest Programming Language" by: Chris Lott DozingDog@thekennel.co - 2021-11-25 11:19 +0000
              Re: "C Is The Greenest Programming Language" by: Chris Lott Juha Nieminen <nospam@thanks.invalid> - 2021-11-25 11:46 +0000
                Re: "C Is The Greenest Programming Language" by: Chris Lott DozingDog@thekennel.co - 2021-11-25 15:57 +0000
              Re: "C Is The Greenest Programming Language" by: Chris Lott Richard Damon <Richard@Damon-Family.org> - 2021-11-25 07:04 -0500
                Re: "C Is The Greenest Programming Language" by: Chris Lott DozingDog@thekennel.co - 2021-11-25 15:59 +0000
                Re: "C Is The Greenest Programming Language" by: Chris Lott Thiago Adams <thiago.adams@gmail.com> - 2021-11-26 03:37 -0800
  Re: "C Is The Greenest Programming Language" by: Chris Lott Manfred <noname@add.invalid> - 2021-11-23 16:03 +0100
    Re: "C Is The Greenest Programming Language" by: Chris Lott gazelle@shell.xmission.com (Kenny McCormack) - 2021-11-23 15:50 +0000
      Re: "C Is The Greenest Programming Language" by: Chris Lott David Brown <david.brown@hesbynett.no> - 2021-11-23 17:51 +0100
        Re: "C Is The Greenest Programming Language" by: Chris Lott DozingDog@thekennel.co - 2021-11-23 17:00 +0000
          Re: "C Is The Greenest Programming Language" by: Chris Lott Richard Damon <Richard@Damon-Family.org> - 2021-11-23 12:36 -0500
          Re: "C Is The Greenest Programming Language" by: Chris Lott David Brown <david.brown@hesbynett.no> - 2021-11-23 19:24 +0100
            Re: "C Is The Greenest Programming Language" by: Chris Lott Richard Damon <Richard@Damon-Family.org> - 2021-11-23 13:50 -0500
              Re: "C Is The Greenest Programming Language" by: Chris Lott David Brown <david.brown@hesbynett.no> - 2021-11-23 20:02 +0100
        Re: "C Is The Greenest Programming Language" by: Chris Lott Manfred <noname@add.invalid> - 2021-11-23 20:59 +0100
          Re: "C Is The Greenest Programming Language" by: Chris Lott Bart <bc@freeuk.com> - 2021-11-23 20:50 +0000
            Re: "C Is The Greenest Programming Language" by: Chris Lott Ian Collins <ian-news@hotmail.com> - 2021-11-24 11:18 +1300
              Re: "C Is The Greenest Programming Language" by: Chris Lott Bart <bc@freeuk.com> - 2021-11-23 22:58 +0000
            Re: "C Is The Greenest Programming Language" by: Chris Lott David Brown <david.brown@hesbynett.no> - 2021-11-23 23:46 +0100
              Re: "C Is The Greenest Programming Language" by: Chris Lott Bart <bc@freeuk.com> - 2021-11-24 13:59 +0000
                Re: "C Is The Greenest Programming Language" by: Chris Lott antispam@math.uni.wroc.pl - 2021-12-11 13:25 +0000
                Re: "C Is The Greenest Programming Language" by: Chris Lott Bart <bc@freeuk.com> - 2021-12-11 14:54 +0000
            Re: "C Is The Greenest Programming Language" by: Chris Lott Manfred <noname@add.invalid> - 2021-11-25 12:12 +0100
          Re: "C Is The Greenest Programming Language" by: Chris Lott David Brown <david.brown@hesbynett.no> - 2021-11-23 23:35 +0100
            Re: "C Is The Greenest Programming Language" by: Chris Lott Manfred <noname@add.invalid> - 2021-11-24 15:30 +0100
              Re: "C Is The Greenest Programming Language" by: Chris Lott Bart <bc@freeuk.com> - 2021-11-24 14:43 +0000
      Re: "C Is The Greenest Programming Language" by: Chris Lott Manfred <noname@add.invalid> - 2021-11-23 20:29 +0100
    Re: "C Is The Greenest Programming Language" by: Chris Lott Bart <bc@freeuk.com> - 2021-11-23 16:14 +0000
    Re: "C Is The Greenest Programming Language" by: Chris Lott Philipp Klaus Krause <pkk@spth.de> - 2021-11-24 11:56 +0100
      Re: "C Is The Greenest Programming Language" by: Chris Lott Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2021-11-24 10:14 -0800
        Re: "C Is The Greenest Programming Language" by: Chris Lott David Brown <david.brown@hesbynett.no> - 2021-11-24 19:55 +0100
          Re: "C Is The Greenest Programming Language" by: Chris Lott Philipp Klaus Krause <pkk@spth.de> - 2021-11-24 21:13 +0100
        Re: "C Is The Greenest Programming Language" by: Chris Lott Philipp Klaus Krause <pkk@spth.de> - 2021-11-24 21:11 +0100
      Re: "C Is The Greenest Programming Language" by: Chris Lott Philipp Klaus Krause <pkk@spth.de> - 2021-11-24 21:17 +0100
        Re: "C Is The Greenest Programming Language" by: Chris Lott Bart <bc@freeuk.com> - 2021-11-24 20:42 +0000
          Re: "C Is The Greenest Programming Language" by: Chris Lott Philipp Klaus Krause <pkk@spth.de> - 2021-11-24 23:25 +0100
          Re: "C Is The Greenest Programming Language" by: Chris Lott antispam@math.uni.wroc.pl - 2021-12-11 14:07 +0000
            Re: "C Is The Greenest Programming Language" by: Chris Lott Bart <bc@freeuk.com> - 2021-12-11 18:46 +0000
              [OT] Lisp.  Was: "C Is The Greenest Programming Language" by: Chris Lott Ben Bacarisse <ben.usenet@bsb.me.uk> - 2021-12-11 20:11 +0000
                Re: "C Is The Greenest Programming Language" Dave Dunfield <dave.dunfield@gmail.com> - 2021-12-13 17:59 -0800
                Re: "C Is The Greenest Programming Language" Ben Bacarisse <ben.usenet@bsb.me.uk> - 2021-12-14 03:18 +0000
                Re: "C Is The Greenest Programming Language" Dave Dunfield <dave.dunfield@gmail.com> - 2021-12-16 10:57 -0800
                Re: "C Is The Greenest Programming Language" Ben Bacarisse <ben.usenet@bsb.me.uk> - 2021-12-16 22:03 +0000
                Re: "C Is The Greenest Programming Language" Dave Dunfield <dave.dunfield@gmail.com> - 2021-12-20 02:40 -0800
                Re: "C Is The Greenest Programming Language" Ben Bacarisse <ben.usenet@bsb.me.uk> - 2021-12-20 12:05 +0000
  Re: "C Is The Greenest Programming Language" by: Chris Lott "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2021-11-24 14:12 -0800
    Re: "C Is The Greenest Programming Language" by: Chris Lott Manfred <noname@add.invalid> - 2021-11-25 12:00 +0100
  Re: "C Is The Greenest Programming Language" by: Chris Lott Paavo Helde <eesnimi@osa.pri.ee> - 2021-12-05 22:51 +0200
    Re: "C Is The Greenest Programming Language" by: Chris Lott "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2021-12-05 19:20 -0800
      Re: "C Is The Greenest Programming Language" by: Chris Lott Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2021-12-06 01:52 -0800
        Re: "C Is The Greenest Programming Language" by: Chris Lott "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2021-12-06 12:19 -0800
          Re: "C Is The Greenest Programming Language" by: Chris Lott "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2021-12-06 12:27 -0800
    Re: "C Is The Greenest Programming Language" by: Chris Lott Manfred <noname@add.invalid> - 2021-12-06 12:28 +0100
      Re: "C Is The Greenest Programming Language" by: Chris Lott Paavo Helde <eesnimi@osa.pri.ee> - 2021-12-06 13:40 +0200
    Re: "C Is The Greenest Programming Language" by: Chris Lott Bonita Montero <Bonita.Montero@gmail.com> - 2021-12-06 16:21 +0100

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