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19 Commits

Author SHA1 Message Date
Wilco Dijkstra 3ae725dfb6 Improve strstr performance 
Improve strstr performance.  Strstr tends to be slow because it uses
many calls to memchr and a slow byte loop to scan for the next match.
Performance is significantly improved by using strnlen on larger blocks
and using strchr to search for the next matching character.  strcasestr
can also use strnlen to scan ahead, and memmem can use memchr to check
for the next match.

On the GLIBC bench tests the performance gains on Cortex-A72 are:
strstr: +25%
strcasestr: +4.3%
memmem: +18%

On a 256KB dataset strstr performance improves by 67%, strcasestr by 47%.

    Reviewd-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
 2018-07-16 17:51:52 +01:00
Joseph Myers 688903eb3e Update copyright dates with scripts/update-copyrights. 
* All files with FSF copyright notices: Update copyright dates
	using scripts/update-copyrights.
	* locale/programs/charmap-kw.h: Regenerated.
	* locale/programs/locfile-kw.h: Likewise.
 2018-01-01 00:32:25 +00:00
Joseph Myers bfff8b1bec Update copyright dates with scripts/update-copyrights. 2017-01-01 00:14:16 +00:00
Joseph Myers f7a9f785e5 Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
Joseph Myers b168057aaa Update copyright dates with scripts/update-copyrights. 2015-01-02 16:29:47 +00:00
Allan McRae d4697bc93d Update copyright notices with scripts/update-copyrights 2014-01-01 22:00:23 +10:00
Tom de Vries a175b684e2 Fix typo, improve comment, remove superfluous #undefs, add missing #undef. 2013-02-12 00:00:49 +01:00
Joseph Myers 568035b787 Update copyright notices with scripts/update-copyrights. 2013-01-02 19:05:09 +00:00
Maxim Kuvyrkov e9f3725206 Fix BZ #14716: memmem crash 2012-10-15 17:22:41 -07:00
Maxim Kuvyrkov 57e605ba50 Fix BZ #14602: strstr and strcasestr return wrong result. 2012-10-08 20:52:53 -07:00
Maxim Kuvyrkov bcca089526 Micro-optimize critical path of strstr, strcase and memmem. 2012-08-21 18:07:47 -07:00
Maxim Kuvyrkov 99677e5755 Use pointers for traversing arrays in strstr, strcasestr and memmem. 2012-08-21 18:07:47 -07:00
Maxim Kuvyrkov 400726deef Detect EOL on-the-fly in strstr, strcasestr and memmem. 2012-08-21 18:07:47 -07:00
Maxim Kuvyrkov 20a71f2c8a Optimize first-character loop of strstr, strcasestr and memmem. 2012-08-21 18:07:47 -07:00
Roland McGrath be75d75807 Remove local redefinition of MAX macro. 2012-08-15 11:40:41 -07:00
Paul Eggert 59ba27a63a Replace FSF snail mail address with URLs. 2012-02-09 23:18:22 +00:00
Eric Blake 5fb308bca2 Fix strstr and memmem algorithm. 2010-10-06 13:48:07 -04:00
Ulrich Drepper dbc676d4ff Add performance tests for strstr and strcasestr. 2010-07-23 22:27:53 -07:00
Ulrich Drepper 0caca71ac9 * string/Makefile (distribute): Add str-two-way.h. 
2008-03-29  Eric Blake	<ebb9@byu.net>

	Rewrite string searches to O(n) rather than O(n^2).
	* string/str-two-way.h: New file.  For linear fixed-allocation
	string searching.
	* string/memmem.c: New implementation.
	* string/strstr.c: New implementation.
	* string/strcasestr.c: New implementation.

	* sysdeps/posix/getaddrinfo.c (getaddrinfo): Call _res_hconf_init
 2008-05-15 04:42:20 +00:00