From: Andreas Ericsson <ae@op5.se>
To: Jeff King <peff@peff.net>
Cc: Paolo Bonzini <paolo.bonzini@gmail.com>,
Junio C Hamano <gitster@pobox.com>, John Bito <jwbito@gmail.com>,
git <git@vger.kernel.org>
Subject: Re: git diff looping?
Date: Wed, 17 Jun 2009 13:31:20 +0200 [thread overview]
Message-ID: <4A38D408.7000302@op5.se> (raw)
In-Reply-To: <20090617102332.GA32353@coredump.intra.peff.net>
Jeff King wrote:
>
> 3. Replace compat/regex with something faster. It still produces
> exponential behavior in complex cases where glibc does not, and it
> seems to be about 1/3 as fast on Paolo's regex.
>
> I haven't looked at how large or how portable the glibc
> implementation is. Another alternative is that we could provide a
> simple compat/ as now, and have better support for linking against
> an external library like pcre, if it is available.
>
The glibc implementation is quite large. Cutting the library-specific
cruft it still sits at about 10k LOC.
Using PCRE is a no-go, as it uses perl-compatible regexes even for the
posix-compatible API, as per pcreposix(3):
When PCRE is called via these functions, it is only the API that is
POSIX-like in style. The syntax and semantics of the regular expres-
sions themselves are still those of Perl, subject to the setting of
various PCRE options, as described below. "POSIX-like in style" means
that the API approximates to the POSIX definition; it is not fully
POSIX-compatible, and in multi-byte encoding domains it is probably
even less compatible.
This would probably surprise some "git grep" users quite a lot, I think.
I like your other two suggestions though. The stuff already in compat/
seems to work well enough, so with Paolo's improved pattern it should
be fine.
--
Andreas Ericsson andreas.ericsson@op5.se
OP5 AB www.op5.se
Tel: +46 8-230225 Fax: +46 8-230231
Considering the successes of the wars on alcohol, poverty, drugs and
terror, I think we should give some serious thought to declaring war
on peace.
next prev parent reply other threads:[~2009-06-17 11:31 UTC|newest]
Thread overview: 37+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-06-16 1:37 git diff looping? John Bito
2009-06-16 2:44 ` Jeff Epler
2009-06-16 2:53 ` John Bito
2009-06-16 11:47 ` Jeff King
2009-06-16 12:07 ` Jeff King
2009-06-16 12:11 ` [PATCH 1/2] Makefile: refactor regex compat support Jeff King
2009-06-16 18:47 ` Johannes Sixt
2009-06-16 19:05 ` Jeff King
2009-06-16 19:07 ` [PATCH v2 " Jeff King
2009-06-16 19:08 ` [PATCH v2 2/2] Makefile: use compat regex on Solaris Jeff King
2009-06-16 20:07 ` Brandon Casey
2009-06-17 13:15 ` Mike Ralphson
2009-06-17 13:55 ` Mike Ralphson
2009-06-16 12:14 ` [PATCH " Jeff King
2009-06-16 15:48 ` git diff looping? John Bito
2009-06-16 16:51 ` Junio C Hamano
2009-06-16 17:15 ` Jeff King
2009-06-16 17:35 ` Brandon Casey
2009-06-16 17:39 ` John Bito
2009-06-16 17:41 ` Jeff King
2009-06-16 20:22 ` Brandon Casey
2009-06-17 8:46 ` Paolo Bonzini
2009-06-17 10:23 ` Jeff King
2009-06-17 11:02 ` Paolo Bonzini
2009-06-17 11:31 ` Andreas Ericsson [this message]
2009-06-17 13:08 ` Paolo Bonzini
2009-06-17 13:16 ` Andreas Ericsson
2009-06-17 13:58 ` Paolo Bonzini
2009-06-17 14:26 ` [PATCH] avoid exponential regex match for java and objc function names Paolo Bonzini
2009-06-17 15:46 ` demerphq
2009-06-17 15:56 ` Jeff King
2009-06-17 16:00 ` demerphq
2009-06-17 16:04 ` Paolo Bonzini
2009-06-17 16:42 ` Junio C Hamano
2009-06-18 6:45 ` Paolo Bonzini
2009-06-16 17:16 ` git diff looping? John Bito
2009-06-16 17:24 ` Jeff King
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
List information: http://vger.kernel.org/majordomo-info.html
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=4A38D408.7000302@op5.se \
--to=ae@op5.se \
--cc=git@vger.kernel.org \
--cc=gitster@pobox.com \
--cc=jwbito@gmail.com \
--cc=paolo.bonzini@gmail.com \
--cc=peff@peff.net \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
Code repositories for project(s) associated with this public inbox
https://80x24.org/mirrors/git.git
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).