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* Update copyright dates with scripts/update-copyrights.Joseph Myers2020-01-011-1/+1
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* Prefer https to http for gnu.org and fsf.org URLsPaul Eggert2019-09-071-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Also, change sources.redhat.com to sourceware.org. This patch was automatically generated by running the following shell script, which uses GNU sed, and which avoids modifying files imported from upstream: sed -ri ' s,(http|ftp)(://(.*\.)?(gnu|fsf|sourceware)\.org($|[^.]|\.[^a-z])),https\2,g s,(http|ftp)(://(.*\.)?)sources\.redhat\.com($|[^.]|\.[^a-z]),https\2sourceware.org\4,g ' \ $(find $(git ls-files) -prune -type f \ ! -name '*.po' \ ! -name 'ChangeLog*' \ ! -path COPYING ! -path COPYING.LIB \ ! -path manual/fdl-1.3.texi ! -path manual/lgpl-2.1.texi \ ! -path manual/texinfo.tex ! -path scripts/config.guess \ ! -path scripts/config.sub ! -path scripts/install-sh \ ! -path scripts/mkinstalldirs ! -path scripts/move-if-change \ ! -path INSTALL ! -path locale/programs/charmap-kw.h \ ! -path po/libc.pot ! -path sysdeps/gnu/errlist.c \ ! '(' -name configure \ -execdir test -f configure.ac -o -f configure.in ';' ')' \ ! '(' -name preconfigure \ -execdir test -f preconfigure.ac ';' ')' \ -print) and then by running 'make dist-prepare' to regenerate files built from the altered files, and then executing the following to cleanup: chmod a+x sysdeps/unix/sysv/linux/riscv/configure # Omit irrelevant whitespace and comment-only changes, # perhaps from a slightly-different Autoconf version. git checkout -f \ sysdeps/csky/configure \ sysdeps/hppa/configure \ sysdeps/riscv/configure \ sysdeps/unix/sysv/linux/csky/configure # Omit changes that caused a pre-commit check to fail like this: # remote: *** error: sysdeps/powerpc/powerpc64/ppc-mcount.S: trailing lines git checkout -f \ sysdeps/powerpc/powerpc64/ppc-mcount.S \ sysdeps/unix/sysv/linux/s390/s390-64/syscall.S # Omit change that caused a pre-commit check to fail like this: # remote: *** error: sysdeps/sparc/sparc64/multiarch/memcpy-ultra3.S: last line does not end in newline git checkout -f sysdeps/sparc/sparc64/multiarch/memcpy-ultra3.S
* Improve performance of strstrWilco Dijkstra2019-06-121-48/+117
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch significantly improves performance of strstr using a novel modified Horspool algorithm. Needles up to size 256 use a bad-character table indexed by hashed pairs of characters to quickly skip past mismatches. Long needles use a self-adapting filtering step to avoid comparing the whole needle repeatedly. By limiting the needle length to 256, the shift table only requires 8 bits per entry, lowering preprocessing overhead and minimizing cache effects. This limit also implies worst-case performance is linear. Small needles up to size 3 use a dedicated linear search. Very long needles use the Two-Way algorithm. The performance gain using the improved bench-strstr on Cortex-A72 is 5.8 times basic_strstr and 3.7 times twoway_strstr. Tested against GLIBC testsuite, randomized tests and the GNULIB strstr test (https://git.savannah.gnu.org/cgit/gnulib.git/tree/tests/test-strstr.c). Reviewed-by: Szabolcs Nagy <szabolcs.nagy@arm.com> * string/str-two-way.h (two_way_short_needle): Add inline to avoid warning. (two_way_long_needle): Block inlining. * string/strstr.c (strstr2): Add new function. (strstr3): Likewise. (STRSTR): Completely rewrite strstr to improve performance.
* Update copyright dates with scripts/update-copyrights.Joseph Myers2019-01-011-1/+1
| | | | | | | * 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.
* Fix strstr bug with huge needles (bug 23637)Wilco Dijkstra2018-09-191-2/+3
| | | | | | | | | | | | | | | The generic strstr in GLIBC 2.28 fails to match huge needles. The optimized AVAILABLE macro reads ahead a large fixed amount to reduce the overhead of repeatedly checking for the end of the string. However if the needle length is larger than this, two_way_long_needle may confuse this as meaning the end of the string and return NULL. This is fixed by adding the needle length to the amount to read ahead. [BZ #23637] * string/test-strstr.c (pr23637): New function. (test_main): Add tests with longer needles. * string/strcasestr.c (AVAILABLE): Fix readahead distance. * string/strstr.c (AVAILABLE): Likewise.
* Simplify and speedup strstr/strcasestr first matchWilco Dijkstra2018-08-031-22/+21
| | | | | | | | | | | | Looking at the benchtests, both strstr and strcasestr spend a lot of time in a slow initialization loop handling one character per iteration. This can be simplified and use the much faster strlen/strnlen/strchr/memcmp. Read ahead a few cachelines to reduce the number of strnlen calls, which improves performance by ~3-4%. This patch improves the time taken for the full strstr benchtest by >40%. * string/strcasestr.c (STRCASESTR): Simplify and speedup first match. * string/strstr.c (AVAILABLE): Likewise.
* Improve strstr performanceWilco Dijkstra2018-07-161-2/+3
| | | | | | | | | | | | | | | | | | 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>
* Update copyright dates with scripts/update-copyrights.Joseph Myers2018-01-011-1/+1
| | | | | | | * 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.
* Update copyright dates with scripts/update-copyrights.Joseph Myers2017-01-011-1/+1
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* Update copyright dates with scripts/update-copyrights.Joseph Myers2016-01-041-1/+1
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* Update copyright dates with scripts/update-copyrights.Joseph Myers2015-01-021-1/+1
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* Update copyright notices with scripts/update-copyrightsAllan McRae2014-01-011-1/+1
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* Update copyright notices with scripts/update-copyrights.Joseph Myers2013-01-021-1/+1
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* Fix BZ #14602: strstr and strcasestr return wrong result.Maxim Kuvyrkov2012-10-081-3/+1
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* Micro-optimize critical path of strstr, strcase and memmem.Maxim Kuvyrkov2012-08-211-0/+1
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* Detect EOL on-the-fly in strstr, strcasestr and memmem.Maxim Kuvyrkov2012-08-211-2/+4
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* Replace FSF snail mail address with URLs.Paul Eggert2012-02-091-3/+2
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* SSE4.2 strstr/strcasestr for x86-64.H.J. Lu2009-07-201-2/+7
| | | | | This patch implements SSE4.2 strstr/strcasestr, using Knuth-Morris-Pratt string searching algorithm.
* * string/Makefile (distribute): Add str-two-way.h. cvs/fedora-glibc-20080515T0735Ulrich Drepper2008-05-151-89/+53
| | | | | | | | | | | | | 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
* Moved to csu/errno-loc.c.Ulrich Drepper2005-12-141-0/+123
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* (CFLAGS-tst-align.c): Add -mpreferred-stack-boundary=4.Ulrich Drepper2004-12-221-123/+0
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* 2.5-18.1Jakub Jelinek2007-07-121-0/+123