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Re: [PATCH] Optimize strstr, strcasestr and memmem

From: Maxim Kuvyrkov <maxim at codesourcery dot com>
To: Joseph S.Myers <joseph at codesourcery dot com>
Cc: <libc-alpha at sourceware dot org>
Date: Wed, 30 May 2012 20:57:43 +1200
Subject: Re: [PATCH] Optimize strstr, strcasestr and memmem
References: <2C516CF2-D083-4C1D-AD27-6A31D381D548@codesourcery.com> <Pine.LNX.4.64.1205271850560.2360@digraph.polyomino.org.uk>

On 28/05/2012, at 6:53 AM, Joseph S. Myers wrote:

> There is an open bug (bug 11607) specifically about strstr slowing down 
> (in particular cases) when the worst-case-linear implementation was 
> introduced.  So the test in that bug may be useful for benchmarking the 
> patch (and if it appears to fix the regression then it will be appropriate 
> to list [BZ #11607] in the ChangeLog entry, etc.).

Joseph, thanks for the pointer.  This bug hits the short-needle case that I focused on in this patch submission.  The patches cut testcase's runtime by 3-5 times, depending on multilib (-m32/-m64).

--
Maxim Kuvyrkov
CodeSourcery / Mentor Graphics

References:
- [PATCH] Optimize strstr, strcasestr and memmem
  - From: Maxim Kuvyrkov
- Re: [PATCH] Optimize strstr, strcasestr and memmem
  - From: Joseph S. Myers

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