Re: code snippet

From	Ian Collins <ian-news@hotmail.com>
Newsgroups	comp.lang.c
Subject	Re: code snippet
Date	2012-01-04 15:44 +1300
Message-ID	<9mhspaFpeqU6@mid.individual.net> (permalink)
References	(16 earlier) <jcvrjq$feg$1@dont-email.me> <4F035609.2E6947C8@bytecraft.com> <20120103113739.535@kylheku.com> <4F036FE2.6B947764@bytecraft.com> <20120103132417.186@kylheku.com>

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On 01/ 4/12 11:04 AM, Kaz Kylheku wrote:
> On 2012-01-03, Walter Banks<walter@bytecraft.com>  wrote:
>>
>>
>> Kaz Kylheku wrote:
>>
>>>> Very few as in some C compilers actually check that everything that can be
>>>> done in asm can be done in C.
>>>
>>> Really? An example or two would go a long way here.
>>
>> http://bytecraft.com/C_versus_Assembly
>
> In machine language, we can, for instance, disable interrupts, flush an
> instruction cache, or save the registers to a stack. To show that everything
> that can be done in assembly can be done in C, you have to show how these
> things are done. The paper does not show such things.
>
> The paper argues that in the domain of translating calculation formulas,
> a compiler can select instructions as well as human programmer. (And that with
> some extensions to C, like "char small @0x15;" or "registerx xreg;" we can even
> coerce the selection of particular operands to match specific instances of
> assembly language.)
>
> This has not been controversial for decades; the paper belongs more in 1966, or
> maybe 1976, than in 2006.

Here I do agree with you.  The only (relatively) recent times I've used 
assembler were for the cases you mention above (in order to model an RTOS).

> These days, if you're finding that you can't beat the C compiler by coding in
> assembly language, chances are it's in large part because the assembly language
> is designed to work well as a target language for C compilers!  That has not
> historically been the case.

Very true.  Another reason is modern compilers can optimise and analyse 
way more code in one pass than the programmer can.  Gone are the days 
when optimiser performance was limited by available RAM.

-- 
Ian Collins

Thread

code snippet "Bill Cunningham" <nospam@nspam.invalid> - 2011-12-18 20:51 -0500
  Re: code snippet Geoff <geoff@invalid.invalid> - 2011-12-18 18:29 -0800
    Re: code snippet "Bill Cunningham" <nospam@nspam.invalid> - 2011-12-18 21:51 -0500
      Re: code snippet "Bill Cunningham" <nospam@nspam.invalid> - 2011-12-18 22:24 -0500
        Re: code snippet Geoff <geoff@invalid.invalid> - 2011-12-18 19:53 -0800
          Re: code snippet "Bill Cunningham" <nospam@nspam.invalid> - 2011-12-18 23:32 -0500
            Re: code snippet Geoff <geoff@invalid.invalid> - 2011-12-18 20:57 -0800
              Re: code snippet "Bill Cunningham" <nospam@nspam.invalid> - 2011-12-19 00:01 -0500
                Re: code snippet Geoff <geoff@invalid.invalid> - 2011-12-18 21:13 -0800
                Re: code snippet "Bill Cunningham" <nospam@nspam.invalid> - 2011-12-19 16:42 -0500
      Re: code snippet Keith Thompson <kst-u@mib.org> - 2011-12-18 20:14 -0800
        Re: code snippet "Bill Cunningham" <nospam@nspam.invalid> - 2011-12-18 23:27 -0500
      Re: code snippet Rui Maciel <rui.maciel@gmail.com> - 2011-12-19 12:33 +0000
        Re: code snippet "Bill Cunningham" <nospam@nspam.invalid> - 2011-12-19 16:33 -0500
          Re: code snippet Rui Maciel <rui.maciel@gmail.com> - 2011-12-20 00:20 +0000
            Re: code snippet "Bill Cunningham" <nospam@nspam.invalid> - 2011-12-19 19:46 -0500
              Re: code snippet Rui Maciel <rui.maciel@gmail.com> - 2011-12-20 01:14 +0000
                Re: code snippet "Bill Cunningham" <nospam@nspam.invalid> - 2011-12-20 15:51 -0500
                Re: code snippet Rui Maciel <rui.maciel@gmail.com> - 2011-12-21 14:11 +0000
                Re: code snippet 88888 Dihedral <dihedral88888@googlemail.com> - 2011-12-21 07:03 -0800
                Re: code snippet Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-12-21 21:41 +0000
                Re: code snippet 88888 Dihedral <dihedral88888@googlemail.com> - 2011-12-21 16:35 -0800
                Re: code snippet Seebs <usenet-nospam@seebs.net> - 2011-12-22 01:03 +0000
                Re: code snippet Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-12-22 03:19 +0000
                Re: code snippet 88888 Dihedral <dihedral88888@googlemail.com> - 2011-12-22 07:11 -0800
                Re: code snippet Seebs <usenet-nospam@seebs.net> - 2011-12-22 16:59 +0000
                Re: code snippet "io_x" <a@b.c.invalid> - 2011-12-22 18:38 +0100
                Re: code snippet 88888 Dihedral <dihedral88888@googlemail.com> - 2011-12-22 10:40 -0800
                Re: code snippet Markus Wichmann <nullplan@gmx.net> - 2011-12-22 19:12 +0100
                Re: code snippet Nick Keighley <nick_keighley_nospam@hotmail.com> - 2011-12-28 03:50 -0800
                Re: code snippet "io_x" <a@b.c.invalid> - 2011-12-28 17:06 +0100
                Re: code snippet "io_x" <a@b.c.invalid> - 2012-01-01 20:04 +0100
                Re: code snippet Nick Keighley <nick_keighley_nospam@hotmail.com> - 2012-01-01 12:38 -0800
                Re: code snippet "io_x" <a@b.c.invalid> - 2012-01-02 10:14 +0100
                Re: code snippet Nick Keighley <nick_keighley_nospam@hotmail.com> - 2012-01-03 04:56 -0800
                Re: code snippet "io_x" <a@b.c.invalid> - 2012-01-03 18:26 +0100
                Re: code snippet Nick Keighley <nick_keighley_nospam@hotmail.com> - 2012-01-04 00:09 -0800
                Re: code snippet Ian Collins <ian-news@hotmail.com> - 2012-01-04 21:53 +1300
                Re: code snippet "io_x" <a@b.c.invalid> - 2012-01-04 16:14 +0100
                Re: code snippet Nick Keighley <nick_keighley_nospam@hotmail.com> - 2012-01-01 12:28 -0800
                Re: code snippet "io_x" <a@b.c.invalid> - 2012-01-02 10:18 +0100
                Re: code snippet Nick Keighley <nick_keighley_nospam@hotmail.com> - 2012-01-03 04:56 -0800
                Re: code snippet "BartC" <bc@freeuk.com> - 2011-12-22 18:05 +0000
                Re: code snippet Seebs <usenet-nospam@seebs.net> - 2011-12-22 18:14 +0000
                Re: code snippet superpollo <superpollo@tznvy.pbz> - 2011-12-22 20:00 +0100
                Re: code snippet Seebs <usenet-nospam@seebs.net> - 2011-12-22 19:08 +0000
                Re: code snippet superpollo <superpollo@tznvy.pbz> - 2011-12-22 22:43 +0100
                Re: code snippet Seebs <usenet-nospam@seebs.net> - 2011-12-22 21:57 +0000
                Re: code snippet BruceS <bruces42@hotmail.com> - 2011-12-23 16:26 -0800
                Re: code snippet Rui Maciel <rui.maciel@gmail.com> - 2011-12-22 19:21 +0000
                Re: code snippet 88888 Dihedral <dihedral88888@googlemail.com> - 2011-12-22 11:33 -0800
                Re: code snippet "io_x" <a@b.c.invalid> - 2011-12-23 09:10 +0100
                Re: code snippet Rui Maciel <rui.maciel@gmail.com> - 2011-12-23 14:43 +0000
                Re: code snippet Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-12-23 17:14 +0000
                Re: code snippet Keith Thompson <kst-u@mib.org> - 2011-12-23 12:10 -0800
                Re: code snippet Walter Banks <walter@bytecraft.com> - 2012-01-03 14:24 -0500
                Re: code snippet Kaz Kylheku <kaz@kylheku.com> - 2012-01-03 19:58 +0000
                Re: code snippet Walter Banks <walter@bytecraft.com> - 2012-01-03 16:15 -0500
                Re: code snippet blp@cs.stanford.edu (Ben Pfaff) - 2012-01-03 13:26 -0800
                Re: code snippet Kaz Kylheku <kaz@kylheku.com> - 2012-01-03 22:04 +0000
                Re: code snippet Ian Collins <ian-news@hotmail.com> - 2012-01-04 15:44 +1300
                Re: code snippet "BartC" <bc@freeuk.com> - 2012-01-04 23:34 +0000
                Re: code snippet James Harris <james.harris.1@googlemail.com> - 2012-01-04 15:57 -0800
                Re: code snippet 88888 Dihedral <dihedral88888@googlemail.com> - 2012-01-05 23:34 -0800
                Re: code snippet Nick Keighley <nick_keighley_nospam@hotmail.com> - 2012-01-06 00:40 -0800
                Re: code snippet Kleuske <kleuske@nowhere.net> - 2012-01-06 10:33 +0000
                Re: code snippet 88888 Dihedral <dihedral88888@googlemail.com> - 2012-01-06 04:30 -0800
                Re: code snippet Ian Collins <ian-news@hotmail.com> - 2012-01-04 15:37 +1300
                Re: code snippet Kaz Kylheku <kaz@kylheku.com> - 2012-01-04 03:37 +0000
                Re: code snippet Ian Collins <ian-news@hotmail.com> - 2012-01-04 20:23 +1300
                Re: code snippet jacob navia <jacob@spamsink.net> - 2011-12-22 18:26 +0100
                Re: code snippet Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-12-22 19:34 +0000
                Re: code snippet 88888 Dihedral <dihedral88888@googlemail.com> - 2011-12-22 11:57 -0800
                Re: code snippet Seebs <usenet-nospam@seebs.net> - 2011-12-22 20:18 +0000
                Re: code snippet 88888 Dihedral <dihedral88888@googlemail.com> - 2011-12-22 12:52 -0800
                Re: code snippet Seebs <usenet-nospam@seebs.net> - 2011-12-22 20:37 +0000
                Re: code snippet 88888 Dihedral <dihedral88888@googlemail.com> - 2011-12-22 13:27 -0800
                Re: code snippet Seebs <usenet-nospam@seebs.net> - 2011-12-22 21:57 +0000
                Re: code snippet 88888 Dihedral <dihedral88888@googlemail.com> - 2011-12-22 14:09 -0800
                Re: code snippet Seebs <usenet-nospam@seebs.net> - 2011-12-22 21:57 +0000
                Re: code snippet 88888 Dihedral <dihedral88888@googlemail.com> - 2011-12-23 04:01 -0800
                Re: code snippet 88888 Dihedral <dihedral88888@googlemail.com> - 2011-12-22 14:24 -0800
                Re: code snippet Seebs <usenet-nospam@seebs.net> - 2011-12-22 21:57 +0000
                Re: code snippet 88888 Dihedral <dihedral88888@googlemail.com> - 2012-01-01 23:06 -0800
                Re: code snippet Hans Vlems <hvlems@freenet.de> - 2011-12-22 23:35 -0800
                Re: code snippet "BartC" <bc@freeuk.com> - 2011-12-23 12:26 +0000
                Re: code snippet jacob navia <jacob@spamsink.net> - 2011-12-23 18:32 +0100
                Re: code snippet Nick Keighley <nick_keighley_nospam@hotmail.com> - 2011-12-28 04:04 -0800
                Re: code snippet "io_x" <a@b.c.invalid> - 2011-12-23 09:10 +0100
                Re: code snippet 88888 Dihedral <dihedral88888@googlemail.com> - 2011-12-25 11:13 -0800
                Re: code snippet Seebs <usenet-nospam@seebs.net> - 2011-12-25 19:31 +0000
                Re: code snippet Rui Maciel <rui.maciel@gmail.com> - 2011-12-26 21:53 +0000
                Re: code snippet 88888 Dihedral <dihedral88888@googlemail.com> - 2011-12-26 16:10 -0800
                Re: code snippet Keith Thompson <kst-u@mib.org> - 2011-12-26 18:11 -0800
                Re: code snippet 88888 Dihedral <dihedral88888@googlemail.com> - 2011-12-26 23:56 -0800
                Re: code snippet "Bill Cunningham" <nospam@nspam.invalid> - 2011-12-20 15:57 -0500
                Re: code snippet Rui Maciel <rui.maciel@gmail.com> - 2011-12-21 12:39 +0000
                Re: code snippet Bill Reid <hormelfree@gmail.com> - 2011-12-22 15:29 -0800
          Re: code snippet Geoff <geoff@invalid.invalid> - 2011-12-19 19:19 -0800
            Re: code snippet "Bill Cunningham" <nospam@nspam.invalid> - 2011-12-20 13:51 -0500
              Re: code snippet Geoff <geoff@invalid.invalid> - 2011-12-20 11:08 -0800
  Re: code snippet Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-12-19 11:37 +0000
    Re: code snippet "Bill Cunningham" <nospam@nspam.invalid> - 2011-12-19 16:38 -0500
      Re: code snippet "Morris Keesan" <mkeesan@post.harvard.edu> - 2011-12-19 17:02 -0500
    Re: code snippet "Bill Cunningham" <nospam@nspam.invalid> - 2011-12-19 17:21 -0500
      Re: code snippet John Gordon <gordon@panix.com> - 2011-12-19 22:35 +0000

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