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Re: Count string in string with loop increase 2, why is this not faster?

Subject	Re: Count string in string with loop increase 2, why is this not faster?
Newsgroups	comp.lang.c
References	(14 earlier) <f93a9bfe-a458-494b-a8fb-78165b6949d2@googlegroups.com> <s9meC.917167$ch5.593863@fx18.am4> <2297ba4e-8d2f-4516-9907-b767f2836897@googlegroups.com> <aToeC.470372$oD1.406285@fx44.am4> <64044642-4874-4fcb-94ae-e8271c184faa@googlegroups.com>
From	bartc <bc@freeuk.com>
Message-ID	<pmseC.673377$QL6.442615@fx20.am4> (permalink)
Organization	virginmedia.com
Date	2018-02-07 01:10 +0000

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On 07/02/2018 00:43, Bart Smissaert wrote:
> For some reason your function gets quite slow (some 4-5x) when you pick a character where the second byte is not zero, eg Char(128).

That one should still have the second byte zero unless wchar_t is 
signed. But on Windows it appears to be unsigned. Try this code:

  double x;
  wchar_t c;

  c=128;
  x=c;

  printf("%f\n",x);

It should display 128.0000.

Anyway I tried a value 30000 for the 1-character find string, and 
injected 30000 as the 6th character of the search string, and couldn't 
see a difference. What strings did you use?

This search is really just working with 16-bit integers; that they 
represent ASCII or UCS2 characters is irrelevant.

(BTW, if using my testonechar() routine, did you ensure the wchar buffer 
is terminated by one word of zeros? If not then it might explain why 
it's taking longer, as it will search memory until it encounters two 
zero bytes.)

-- 
bartc

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Count string in string with loop increase 2, why is this not faster? Bart Smissaert <bart.smissaert@gmail.com> - 2018-02-03 00:00 -0800
Re: Count string in string with loop increase 2, why is this not faster? bartc <bc@freeuk.com> - 2018-02-03 11:29 +0000
Re: Count string in string with loop increase 2, why is this not faster? Bart Smissaert <bart.smissaert@gmail.com> - 2018-02-03 03:37 -0800
Re: Count string in string with loop increase 2, why is this not faster? bartc <bc@freeuk.com> - 2018-02-03 12:29 +0000
Re: Count string in string with loop increase 2, why is this not faster? Bart Smissaert <bart.smissaert@gmail.com> - 2018-02-03 04:37 -0800
Re: Count string in string with loop increase 2, why is this not faster? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2018-02-03 13:41 +0000
Re: Count string in string with loop increase 2, why is this not faster? Bart Smissaert <bart.smissaert@gmail.com> - 2018-02-03 06:38 -0800
Re: Count string in string with loop increase 2, why is this not faster? bartc <bc@freeuk.com> - 2018-02-03 15:13 +0000
Re: Count string in string with loop increase 2, why is this not faster? bartc <bc@freeuk.com> - 2018-02-03 15:19 +0000
Re: Count string in string with loop increase 2, why is this not faster? Bart Smissaert <bart.smissaert@gmail.com> - 2018-02-03 07:41 -0800
Re: Count string in string with loop increase 2, why is this not faster? Richard Damon <Richard@Damon-Family.org> - 2018-02-03 11:38 -0500
Re: Count string in string with loop increase 2, why is this not faster? bartc <bc@freeuk.com> - 2018-02-03 13:50 +0000
Re: Count string in string with loop increase 2, why is this not faster? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2018-02-03 11:34 +0000
Re: Count string in string with loop increase 2, why is this not faster? Richard Damon <Richard@Damon-Family.org> - 2018-02-03 11:32 -0500
Re: Count string in string with loop increase 2, why is this not faster? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2018-02-03 16:41 +0000
Re: Count string in string with loop increase 2, why is this not faster? Bart Smissaert <bart.smissaert@gmail.com> - 2018-02-03 09:02 -0800
Re: Count string in string with loop increase 2, why is this not faster? Bart Smissaert <bart.smissaert@gmail.com> - 2018-02-03 09:06 -0800
Re: Count string in string with loop increase 2, why is this not faster? Richard Damon <Richard@Damon-Family.org> - 2018-02-03 12:39 -0500
Re: Count string in string with loop increase 2, why is this not faster? Bart Smissaert <bart.smissaert@gmail.com> - 2018-02-03 11:56 -0800
Re: Count string in string with loop increase 2, why is this not faster? Richard Damon <Richard@Damon-Family.org> - 2018-02-03 19:54 -0500
Re: Count string in string with loop increase 2, why is this not faster? Keith Thompson <kst-u@mib.org> - 2018-02-03 18:00 -0800
Re: Count string in string with loop increase 2, why is this not faster? Bart Smissaert <bart.smissaert@gmail.com> - 2018-02-04 01:53 -0800
Re: Count string in string with loop increase 2, why is this not faster? Richard Damon <Richard@Damon-Family.org> - 2018-02-04 13:23 -0500
Re: Count string in string with loop increase 2, why is this not faster? Bart Smissaert <bart.smissaert@gmail.com> - 2018-02-04 11:11 -0800
Re: Count string in string with loop increase 2, why is this not faster? Richard Damon <Richard@Damon-Family.org> - 2018-02-04 14:48 -0500
Re: Count string in string with loop increase 2, why is this not faster? Bart Smissaert <bart.smissaert@gmail.com> - 2018-02-04 12:17 -0800
Re: Count string in string with loop increase 2, why is this not faster? bartc <bc@freeuk.com> - 2018-02-04 21:53 +0000
Re: Count string in string with loop increase 2, why is this not faster? Bart Smissaert <bart.smissaert@gmail.com> - 2018-02-04 14:35 -0800
Re: Count string in string with loop increase 2, why is this not faster? bartc <bc@freeuk.com> - 2018-02-04 23:32 +0000
Re: Count string in string with loop increase 2, why is this not faster? Bart Smissaert <bart.smissaert@gmail.com> - 2018-02-05 06:26 -0800
Re: Count string in string with loop increase 2, why is this not faster? bartc <bc@freeuk.com> - 2018-02-05 16:59 +0000
Re: Count string in string with loop increase 2, why is this not faster? Bart Smissaert <bart.smissaert@gmail.com> - 2018-02-05 09:44 -0800
Re: Count string in string with loop increase 2, why is this not faster? bartc <bc@freeuk.com> - 2018-02-05 18:28 +0000
Re: Count string in string with loop increase 2, why is this not faster? scott@slp53.sl.home (Scott Lurndal) - 2018-02-05 18:41 +0000
Re: Count string in string with loop increase 2, why is this not faster? bartc <bc@freeuk.com> - 2018-02-05 20:08 +0000
Re: Count string in string with loop increase 2, why is this not faster? scott@slp53.sl.home (Scott Lurndal) - 2018-02-05 21:27 +0000
Re: Count string in string with loop increase 2, why is this not faster? bartc <bc@freeuk.com> - 2018-02-05 22:04 +0000
Re: Count string in string with loop increase 2, why is this not faster? scott@slp53.sl.home (Scott Lurndal) - 2018-02-05 22:38 +0000
Re: Count string in string with loop increase 2, why is this not faster? bartc <bc@freeuk.com> - 2018-02-06 01:34 +0000
Re: Count string in string with loop increase 2, why is this not faster? Bart Smissaert <bart.smissaert@gmail.com> - 2018-02-06 06:39 -0800
Re: Count string in string with loop increase 2, why is this not faster? bartc <bc@freeuk.com> - 2018-02-06 18:07 +0000
Re: Count string in string with loop increase 2, why is this not faster? Bart Smissaert <bart.smissaert@gmail.com> - 2018-02-06 12:34 -0800
Re: Count string in string with loop increase 2, why is this not faster? bartc <bc@freeuk.com> - 2018-02-06 21:12 +0000
Re: Count string in string with loop increase 2, why is this not faster? Bart Smissaert <bart.smissaert@gmail.com> - 2018-02-06 13:42 -0800
Re: Count string in string with loop increase 2, why is this not faster? Bart Smissaert <bart.smissaert@gmail.com> - 2018-02-06 16:43 -0800
Re: Count string in string with loop increase 2, why is this not faster? bartc <bc@freeuk.com> - 2018-02-07 01:10 +0000
Re: Count string in string with loop increase 2, why is this not faster? Keith Thompson <kst-u@mib.org> - 2018-02-06 18:47 -0800
Re: Count string in string with loop increase 2, why is this not faster? David Brown <david.brown@hesbynett.no> - 2018-02-07 15:13 +0100
Re: Count string in string with loop increase 2, why is this not faster? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2018-02-07 14:48 +0000
Re: Count string in string with loop increase 2, why is this not faster? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2018-02-07 17:13 +0000
Re: Count string in string with loop increase 2, why is this not faster? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2018-02-07 17:27 +0000
Re: Count string in string with loop increase 2, why is this not faster? David Brown <david.brown@hesbynett.no> - 2018-02-07 17:01 +0100
Re: Count string in string with loop increase 2, why is this not faster? Bart Smissaert <bart.smissaert@gmail.com> - 2018-02-07 02:00 -0800
Re: Count string in string with loop increase 2, why is this not faster? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2018-02-07 12:02 +0000
Re: Count string in string with loop increase 2, why is this not faster? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2018-02-07 14:46 +0000
Re: Count string in string with loop increase 2, why is this not faster? bartc <bc@freeuk.com> - 2018-02-07 13:56 +0000
Re: Count string in string with loop increase 2, why is this not faster? bartc <bc@freeuk.com> - 2018-02-07 11:17 +0000
Re: Count string in string with loop increase 2, why is this not faster? Bart Smissaert <bart.smissaert@gmail.com> - 2018-02-06 23:59 -0800
Re: Count string in string with loop increase 2, why is this not faster? Bart Smissaert <bart.smissaert@gmail.com> - 2018-02-07 05:10 -0800
Re: Count string in string with loop increase 2, why is this not faster? bartc <bc@freeuk.com> - 2018-02-07 11:01 +0000
Re: Count string in string with loop increase 2, why is this not faster? Bart Smissaert <bart.smissaert@gmail.com> - 2018-02-07 14:24 -0800
Re: Count string in string with loop increase 2, why is this not faster? Bart Smissaert <bart.smissaert@gmail.com> - 2018-02-07 14:44 -0800
Re: Count string in string with loop increase 2, why is this not faster? bartc <bc@freeuk.com> - 2018-02-07 22:59 +0000
Re: Count string in string with loop increase 2, why is this not faster? Keith Thompson <kst-u@mib.org> - 2018-02-07 15:20 -0800
Re: Count string in string with loop increase 2, why is this not faster? bartc <bc@freeuk.com> - 2018-02-07 23:31 +0000
Re: Count string in string with loop increase 2, why is this not faster? Bart Smissaert <bart.smissaert@gmail.com> - 2018-02-07 15:32 -0800
Re: Count string in string with loop increase 2, why is this not faster? Keith Thompson <kst-u@mib.org> - 2018-02-07 16:05 -0800
Re: Count string in string with loop increase 2, why is this not faster? Bart Smissaert <bart.smissaert@gmail.com> - 2018-02-05 15:29 -0800
Re: Count string in string with loop increase 2, why is this not faster? Richard Damon <Richard@Damon-Family.org> - 2018-02-04 17:41 -0500
Re: Count string in string with loop increase 2, why is this not faster? bartc <bc@freeuk.com> - 2018-02-04 23:11 +0000
Re: Count string in string with loop increase 2, why is this not faster? Richard Damon <Richard@Damon-Family.org> - 2018-02-04 23:45 -0500
Re: Count string in string with loop increase 2, why is this not faster? Keith Thompson <kst-u@mib.org> - 2018-02-04 15:11 -0800
Re: Count string in string with loop increase 2, why is this not faster? bartc <bc@freeuk.com> - 2018-02-04 23:37 +0000
Re: Count string in string with loop increase 2, why is this not faster? Keith Thompson <kst-u@mib.org> - 2018-02-04 18:08 -0800
Re: Count string in string with loop increase 2, why is this not faster? Richard Damon <Richard@Damon-Family.org> - 2018-02-04 23:12 -0500
Re: Count string in string with loop increase 2, why is this not faster? David Brown <david.brown@hesbynett.no> - 2018-02-05 13:08 +0100
Re: Count string in string with loop increase 2, why is this not faster? Richard Damon <Richard@Damon-Family.org> - 2018-02-05 08:24 -0500
Re: Count string in string with loop increase 2, why is this not faster? David Brown <david.brown@hesbynett.no> - 2018-02-05 14:39 +0100
Re: Count string in string with loop increase 2, why is this not faster? Robert Wessel <robertwessel2@yahoo.com> - 2018-02-05 10:37 -0600
Re: Count string in string with loop increase 2, why is this not faster? supercat@casperkitty.com - 2018-02-05 13:52 -0800
Re: Count string in string with loop increase 2, why is this not faster? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2018-02-05 22:29 +0000
Re: Count string in string with loop increase 2, why is this not faster? Keith Thompson <kst-u@mib.org> - 2018-02-05 09:01 -0800
Re: Count string in string with loop increase 2, why is this not faster? bartc <bc@freeuk.com> - 2018-02-05 18:44 +0000
Re: Count string in string with loop increase 2, why is this not faster? David Brown <david.brown@hesbynett.no> - 2018-02-06 10:42 +0100
Re: Count string in string with loop increase 2, why is this not faster? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2018-02-06 11:17 +0000
Re: Count string in string with loop increase 2, why is this not faster? Richard Damon <Richard@Damon-Family.org> - 2018-02-06 08:40 -0500
Re: Count string in string with loop increase 2, why is this not faster? bartc <bc@freeuk.com> - 2018-02-06 14:08 +0000
Re: Count string in string with loop increase 2, why is this not faster? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2018-02-06 14:42 +0000
Re: Count string in string with loop increase 2, why is this not faster? Keith Thompson <kst-u@mib.org> - 2018-02-06 12:35 -0800
Re: Count string in string with loop increase 2, why is this not faster? David Brown <david.brown@hesbynett.no> - 2018-02-06 23:04 +0100
Re: Count string in string with loop increase 2, why is this not faster? Richard Damon <Richard@Damon-Family.org> - 2018-02-04 17:35 -0500
Re: Count string in string with loop increase 2, why is this not faster? Bart Smissaert <bart.smissaert@gmail.com> - 2018-02-04 14:38 -0800
Re: Count string in string with loop increase 2, why is this not faster? Richard Damon <Richard@Damon-Family.org> - 2018-02-04 17:57 -0500
Re: Count string in string with loop increase 2, why is this not faster? Bart Smissaert <bart.smissaert@gmail.com> - 2018-02-04 15:22 -0800
Re: Count string in string with loop increase 2, why is this not faster? Bart Smissaert <bart.smissaert@gmail.com> - 2018-02-04 12:19 -0800
Re: Count string in string with loop increase 2, why is this not faster? Richard Damon <Richard@Damon-Family.org> - 2018-02-04 16:42 -0500
Re: Count string in string with loop increase 2, why is this not faster? Keith Thompson <kst-u@mib.org> - 2018-02-03 13:38 -0800
Re: Count string in string with loop increase 2, why is this not faster? Jorgen Grahn <grahn+nntp@snipabacken.se> - 2018-02-03 22:03 +0000

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