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Re: memscan() function or equivalent

Subject Re: memscan() function or equivalent
Newsgroups comp.lang.c
References (9 earlier) <20170610095607.15b3f941329ac52c99c802d6@gmail.com> <593c0cd5$0$8957$426a34cc@news.free.fr> <20170610173847.891e1259cdb92ffbd65febf9@gmail.com> <cbed16ac-7ae7-462a-9d9a-b5deaa7fb7c5@googlegroups.com> <20170610234025.fb059715af3dc8f5301a2224@gmail.com>
From bartc <bc@freeuk.com>
Message-ID <ph__A.28502$9M.11355@fx18.am4> (permalink)
Organization virginmedia.com
Date 2017-06-10 23:21 +0100

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On 10/06/2017 22:40, GOTHIER Nathan wrote:
> On Sat, 10 Jun 2017 11:52:29 -0700 (PDT)
> David Kleinecke <dkleinecke@gmail.com> wrote:
> 
>> But from the point of view of what is easier to "understand" I
>> suspect the form in goto's has more popular appeal.
> 
> Indeed. I am stunned by the fierce opposition to labels and goto while many
> detractors acknowledge its incredible power for corner cases where they are
> unable to express clearly their algorithm with a higher level loop structure.

Here's the Sieve benchmark [prime number thing] as I generate it now as 
C code (assume some typedefs, not shown):

  int32   count;
  int32   i;
  int32   k;
  int32   prime;
  int32   av_1;
      count = 0;
      av_1 = 20000;
      while (av_1--) {
          for (i=1; i<=8192; ++i) {
              data[i-1] = 1;
          }
          for (i=1; i<=8192; ++i) {
              if (!!data[i-1]) {
                  k = (prime = i+i+3)+i;
                  while (k <= 8192) {
                      data[k-1] = 0;
                      k += prime;
                  }
                  ++count;
              }
          }
      }
      printf("%s %d\n","Count =",count);
  }

Here's what it looks like as 'flat' C code with if/goto and no other 
structuring (and with simple expressions):

i32 count;
i32 i;
i32 k;
i32 prime;
i32 av$1;
byte $1;
i32 $2;

  count = 0;
  av$1 = 20000;
L2:
L5:
  i = 1;
L6:
  *(data+i-1) = 1;
L7:
  ++i;
  if (i <= 8190) goto L6;
L8:
L9:
  i = 1;
L10:
  $1 = *(data+i-1);
  if (!$1) goto L13;
  $2 = i+i;
  prime = $2+3;
  k = i+prime;
  goto L15;
L14:
  *(data+k-1) = 0;
  k = k+prime;
L15:
  if (k <= 8190) goto L14;
L16:
  ++count;
L13:
L11:
  ++i;
  if (i <= 8190) goto L10;
L12:
L3:
  --av$1;
  if (av$1) goto L2;
L4:
  $startprintcon();
  $prints("Count =");
  $printi(count);
  $println();
  $endprint();
L1:

Don't tell me you think the latter is easier to understand.

-- 
bartc

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memscan() function or equivalent "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2017-06-07 06:16 -0700
  Re: memscan() function or equivalent GOTHIER Nathan <nathan.gothier@gmail.com> - 2017-06-07 15:47 +0200
    Re: memscan() function or equivalent "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2017-06-07 07:15 -0700
      Re: memscan() function or equivalent scott@slp53.sl.home (Scott Lurndal) - 2017-06-07 14:34 +0000
        Re: memscan() function or equivalent "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2017-06-07 07:42 -0700
          Re: memscan() function or equivalent scott@slp53.sl.home (Scott Lurndal) - 2017-06-07 14:45 +0000
            Re: memscan() function or equivalent "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2017-06-07 08:07 -0700
              Re: memscan() function or equivalent jameskuyper@verizon.net - 2017-06-07 09:14 -0700
                Re: memscan() function or equivalent "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2017-06-07 09:33 -0700
      Re: memscan() function or equivalent GOTHIER Nathan <nathan.gothier@gmail.com> - 2017-06-07 16:48 +0200
        Re: memscan() function or equivalent "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2017-06-07 08:31 -0700
          Re: memscan() function or equivalent GOTHIER Nathan <nathan.gothier@gmail.com> - 2017-06-07 17:37 +0200
            Re: memscan() function or equivalent "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2017-06-07 08:47 -0700
              Re: memscan() function or equivalent GOTHIER Nathan <nathan.gothier@gmail.com> - 2017-06-07 18:02 +0200
                Re: memscan() function or equivalent "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2017-06-07 09:09 -0700
                Re: memscan() function or equivalent GOTHIER Nathan <nathan.gothier@gmail.com> - 2017-06-07 18:34 +0200
                Re: memscan() function or equivalent "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2017-06-07 09:54 -0700
                Re: memscan() function or equivalent GOTHIER Nathan <nathan.gothier@gmail.com> - 2017-06-07 19:01 +0200
                Re: memscan() function or equivalent "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2017-06-07 10:17 -0700
                Re: memscan() function or equivalent GOTHIER Nathan <nathan.gothier@gmail.com> - 2017-06-07 19:53 +0200
                Re: memscan() function or equivalent asetofsymbols@gmail.com - 2017-06-07 22:15 -0700
                Re: memscan() function or equivalent asetofsymbols@gmail.com - 2017-06-07 22:26 -0700
                Re: memscan() function or equivalent asetofsymbols@gmail.com - 2017-06-07 22:56 -0700
                Re: memscan() function or equivalent asetofsymbols@gmail.com - 2017-06-07 23:03 -0700
            Re: memscan() function or equivalent scott@slp53.sl.home (Scott Lurndal) - 2017-06-07 16:10 +0000
              Re: memscan() function or equivalent "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2017-06-07 09:30 -0700
        Re: memscan() function or equivalent Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-06-07 16:50 +0100
          Re: memscan() function or equivalent "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2017-06-07 08:58 -0700
            Re: memscan() function or equivalent "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2017-06-07 09:03 -0700
              Re: memscan() function or equivalent "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2017-06-07 09:07 -0700
              Re: memscan() function or equivalent bartc <bc@freeuk.com> - 2017-06-07 17:30 +0100
                Re: memscan() function or equivalent "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2017-06-07 09:36 -0700
                Re: memscan() function or equivalent bartc <bc@freeuk.com> - 2017-06-07 17:48 +0100
                Re: memscan() function or equivalent "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2017-06-07 09:57 -0700
                Re: memscan() function or equivalent Ike Naar <ike@iceland.freeshell.org> - 2017-06-12 05:54 +0000
                Re: memscan() function or equivalent Keith Thompson <kst-u@mib.org> - 2017-06-07 09:48 -0700
                Re: memscan() function or equivalent Gareth Owen <gwowen@gmail.com> - 2017-06-07 20:55 +0100
                Re: memscan() function or equivalent bartc <bc@freeuk.com> - 2017-06-07 22:13 +0100
                Re: memscan() function or equivalent Keith Thompson <kst-u@mib.org> - 2017-06-07 16:02 -0700
                Re: memscan() function or equivalent bartc <bc@freeuk.com> - 2017-06-08 01:26 +0100
                Re: memscan() function or equivalent Ian Collins <ian-news@hotmail.com> - 2017-06-08 13:00 +1200
                Re: memscan() function or equivalent bartc <bc@freeuk.com> - 2017-06-08 09:48 +0100
                Re: memscan() function or equivalent "Patrick.Schluter" <Patrick.Schluter@free.fr> - 2017-06-10 08:52 +0200
            Re: memscan() function or equivalent supercat@casperkitty.com - 2017-06-07 10:00 -0700
              Re: memscan() function or equivalent "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2017-06-07 10:13 -0700
                Re: memscan() function or equivalent supercat@casperkitty.com - 2017-06-07 11:19 -0700
                Re: memscan() function or equivalent "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2017-06-07 11:27 -0700
            Re: memscan() function or equivalent Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-06-07 21:18 +0100
          Re: memscan() function or equivalent GOTHIER Nathan <nathan.gothier@gmail.com> - 2017-06-07 18:18 +0200
            Re: memscan() function or equivalent "Patrick.Schluter" <Patrick.Schluter@free.fr> - 2017-06-07 21:15 +0200
              Re: memscan() function or equivalent GOTHIER Nathan <nathan.gothier@gmail.com> - 2017-06-07 21:16 +0200
                Re: memscan() function or equivalent "Patrick.Schluter" <Patrick.Schluter@free.fr> - 2017-06-10 09:08 +0200
                Re: memscan() function or equivalent GOTHIER Nathan <nathan.gothier@gmail.com> - 2017-06-10 09:56 +0200
                Re: memscan() function or equivalent "Patrick.Schluter" <Patrick.Schluter@free.fr> - 2017-06-10 17:14 +0200
                Re: memscan() function or equivalent GOTHIER Nathan <nathan.gothier@gmail.com> - 2017-06-10 17:38 +0200
                Re: memscan() function or equivalent David Kleinecke <dkleinecke@gmail.com> - 2017-06-10 11:52 -0700
                Re: memscan() function or equivalent bartc <bc@freeuk.com> - 2017-06-10 20:03 +0100
                Re: memscan() function or equivalent Keith Thompson <kst-u@mib.org> - 2017-06-10 13:32 -0700
                Re: memscan() function or equivalent GOTHIER Nathan <nathan.gothier@gmail.com> - 2017-06-10 23:40 +0200
                Re: memscan() function or equivalent Anton Shepelev <anton.txt@gmail.com> - 2017-06-11 00:53 +0300
                Re: memscan() function or equivalent Anton Shepelev <anton.txt@gmail.com> - 2017-06-11 01:11 +0300
                Re: memscan() function or equivalent Ian Collins <ian-news@hotmail.com> - 2017-06-11 10:26 +1200
                Re: memscan() function or equivalent GOTHIER Nathan <nathan.gothier@gmail.com> - 2017-06-11 00:32 +0200
                Re: memscan() function or equivalent "Patrick.Schluter" <Patrick.Schluter@free.fr> - 2017-06-11 10:05 +0200
                Re: memscan() function or equivalent GOTHIER Nathan <nathan.gothier@gmail.com> - 2017-06-11 10:06 +0200
                Re: memscan() function or equivalent Keith Thompson <kst-u@mib.org> - 2017-06-11 13:19 -0700
                Re: memscan() function or equivalent Anton Shepelev <anton.txt@gmail.com> - 2017-06-11 02:17 +0300
                Re: memscan() function or equivalent supercat@casperkitty.com - 2017-06-10 15:21 -0700
                Re: memscan() function or equivalent GOTHIER Nathan <nathan.gothier@gmail.com> - 2017-06-11 00:19 +0200
                Re: memscan() function or equivalent Anton Shepelev <anton.txt@gmail.com> - 2017-06-11 02:15 +0300
                Re: memscan() function or equivalent "Patrick.Schluter" <Patrick.Schluter@free.fr> - 2017-06-11 10:36 +0200
                Re: memscan() function or equivalent GOTHIER Nathan <nathan.gothier@gmail.com> - 2017-06-11 10:46 +0200
                Re: memscan() function or equivalent asetofsymbols@gmail.com - 2017-06-10 22:25 -0700
                Re: memscan() function or equivalent "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2017-06-10 15:13 -0700
                Re: memscan() function or equivalent bartc <bc@freeuk.com> - 2017-06-10 23:21 +0100
                Re: memscan() function or equivalent GOTHIER Nathan <nathan.gothier@gmail.com> - 2017-06-11 00:28 +0200
                Re: memscan() function or equivalent bartc <bc@freeuk.com> - 2017-06-11 10:56 +0100
                Re: memscan() function or equivalent GOTHIER Nathan <nathan.gothier@gmail.com> - 2017-06-11 13:27 +0200
                Re: memscan() function or equivalent bartc <bc@freeuk.com> - 2017-06-11 13:19 +0100
                Re: memscan() function or equivalent Ike Naar <ike@iceland.freeshell.org> - 2017-06-11 18:36 +0000
                Re: memscan() function or equivalent bartc <bc@freeuk.com> - 2017-06-11 20:22 +0100
                Re: memscan() function or equivalent Ike Naar <ike@iceland.freeshell.org> - 2017-06-12 06:09 +0000
                Re: memscan() function or equivalent bartc <bc@freeuk.com> - 2017-06-12 10:38 +0100
                Re: memscan() function or equivalent asetofsymbols@gmail.com - 2017-06-12 05:30 -0700
                Re: memscan() function or equivalent Ike Naar <ike@iceland.freeshell.org> - 2017-06-12 13:51 +0000
                Re: memscan() function or equivalent bartc <bc@freeuk.com> - 2017-06-12 15:04 +0100
                Re: memscan() function or equivalent Ike Naar <ike@iceland.freeshell.org> - 2017-06-12 21:26 +0000
                Re: memscan() function or equivalent "Patrick.Schluter" <Patrick.Schluter@free.fr> - 2017-06-11 10:04 +0200
                Re: memscan() function or equivalent GOTHIER Nathan <nathan.gothier@gmail.com> - 2017-06-11 10:13 +0200
                Re: memscan() function or equivalent "Patrick.Schluter" <Patrick.Schluter@free.fr> - 2017-06-11 13:38 +0200
                Re: memscan() function or equivalent GOTHIER Nathan <nathan.gothier@gmail.com> - 2017-06-11 14:18 +0200
                Re: memscan() function or equivalent supercat@casperkitty.com - 2017-06-11 09:57 -0700
                Re: memscan() function or equivalent Melzzzzz <Melzzzzz@zzzzz.com> - 2017-06-11 17:18 +0000
                Re: memscan() function or equivalent "Patrick.Schluter" <Patrick.Schluter@free.fr> - 2017-06-11 09:53 +0200
                Re: memscan() function or equivalent GOTHIER Nathan <nathan.gothier@gmail.com> - 2017-06-11 10:00 +0200
                Re: memscan() function or equivalent "Patrick.Schluter" <Patrick.Schluter@free.fr> - 2017-06-11 13:41 +0200
              Re: memscan() function or equivalent GOTHIER Nathan <nathan.gothier@gmail.com> - 2017-06-07 21:24 +0200
              Re: memscan() function or equivalent GOTHIER Nathan <nathan.gothier@gmail.com> - 2017-06-07 21:55 +0200
          Re: memscan() function or equivalent Gareth Owen <gwowen@gmail.com> - 2017-06-07 20:54 +0100
            Re: memscan() function or equivalent David Brown <david.brown@hesbynett.no> - 2017-06-07 23:00 +0200
              Re: memscan() function or equivalent Gareth Owen <gwowen@gmail.com> - 2017-06-08 08:16 +0100
                Re: memscan() function or equivalent David Brown <david.brown@hesbynett.no> - 2017-06-08 10:55 +0200
                Re: memscan() function or equivalent Gareth Owen <gwowen@gmail.com> - 2017-06-08 11:44 +0100
                Re: memscan() function or equivalent David Brown <david.brown@hesbynett.no> - 2017-06-08 13:11 +0200
                Re: memscan() function or equivalent Gareth Owen <gwowen@gmail.com> - 2017-06-08 13:45 +0100
                Re: memscan() function or equivalent David Brown <david.brown@hesbynett.no> - 2017-06-08 14:51 +0200
                Re: memscan() function or equivalent supercat@casperkitty.com - 2017-06-08 08:00 -0700
          Re: memscan() function or equivalent Tim Rentsch <txr@alumni.caltech.edu> - 2017-06-09 12:26 -0700
            Re: memscan() function or equivalent Gareth Owen <gwowen@gmail.com> - 2017-06-10 07:24 +0100
              Re: memscan() function or equivalent Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-06-10 13:17 +0100
                Re: memscan() function or equivalent Gareth Owen <gwowen@gmail.com> - 2017-06-10 17:18 +0100
                Re: memscan() function or equivalent Ike Naar <ike@iceland.freeshell.org> - 2017-06-11 18:11 +0000
              Re: memscan() function or equivalent Tim Rentsch <txr@alumni.caltech.edu> - 2017-06-11 15:08 -0700
                Re: memscan() function or equivalent Gareth Owen <gwowen@gmail.com> - 2017-06-12 18:34 +0100
                Re: memscan() function or equivalent Tim Rentsch <txr@alumni.caltech.edu> - 2017-06-14 09:52 -0700
                Re: memscan() function or equivalent Gareth Owen <gwowen@gmail.com> - 2017-06-14 19:56 +0100
                Re: memscan() function or equivalent Keith Thompson <kst-u@mib.org> - 2017-06-14 12:20 -0700
                Re: memscan() function or equivalent Tim Rentsch <txr@alumni.caltech.edu> - 2017-06-17 06:37 -0700
                Re: memscan() function or equivalent supercat@casperkitty.com - 2017-06-17 10:02 -0700
      Re: memscan() function or equivalent David Brown <david.brown@hesbynett.no> - 2017-06-07 16:51 +0200
        Re: memscan() function or equivalent GOTHIER Nathan <nathan.gothier@gmail.com> - 2017-06-07 17:00 +0200
          Re: memscan() function or equivalent supercat@casperkitty.com - 2017-06-07 08:53 -0700

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