From: Sven LUTHER <luther@dpt-info.u-strasbg.fr>
To: Chris Hecker <checker@d6.com>
Cc: eijiro_sumii@anet.ne.jp, caml-list@inria.fr,
gerd@gerd-stolpmann.de, sumii@venus.is.s.u-tokyo.ac.jp
Subject: Re: substring match like "strstr"
Date: Tue, 12 Dec 2000 11:07:19 +0100 [thread overview]
Message-ID: <20001212110719.B25607@lambda.u-strasbg.fr> (raw)
In-Reply-To: <4.3.2.7.2.20001211103237.00c12100@shell16.ba.best.com>; from checker@d6.com on Mon, Dec 11, 2000 at 01:07:22PM -0800
On Mon, Dec 11, 2000 at 01:07:22PM -0800, Chris Hecker wrote:
>
> >The results (execution time in seconds) were as follows.
> > strstr 55.74
> > regexp 154.37
> > OCamlA 302.57
> > OCamlB 129.23
>
> Any ideas why strstr blows the others away? What's the libc strstr look like? I just looked in the MSVC source and it's a braindead while loop (copied below), so it's not like it's doing a fancy Boyer-Moore or anything. This is exactly the kind of problem on which I'd expect caml to come within 10% of c.
Is this kind of thing not one of the field which can take advantage of the
vector units included in the processor, like mmx, altivec and the equivalent
in alpha or sparc processors ? Not sure though, it would depend on the actual
implementation used and command set.
Friendly,
Sven Luther
next prev parent reply other threads:[~2000-12-14 17:48 UTC|newest]
Thread overview: 23+ messages / expand[flat|nested] mbox.gz Atom feed top
2000-12-08 6:04 eijiro_sumii
2000-12-08 12:57 ` Gerd Stolpmann
2000-12-10 13:16 ` eijiro_sumii
2000-12-10 15:39 ` Gerd Stolpmann
2000-12-11 3:57 ` eijiro_sumii
2000-12-12 13:58 ` Julian Assange
2000-12-11 21:07 ` Chris Hecker
2000-12-11 22:22 ` Gerd Stolpmann
2000-12-12 5:06 ` Chris Hecker
2000-12-12 12:28 ` Jean-Christophe Filliatre
2000-12-13 10:02 ` eijiro_sumii
2000-12-13 10:17 ` Eijiro Sumii
2000-12-13 10:53 ` Julian Assange
2000-12-13 13:28 ` Eijiro Sumii
2000-12-12 3:28 ` eijiro_sumii
2000-12-13 1:12 ` John Prevost
2000-12-13 2:35 ` Chris Hecker
2000-12-12 10:07 ` Sven LUTHER [this message]
2000-12-14 3:36 ` eijiro_sumii
2000-12-14 6:48 ` Chris Hecker
2000-12-14 8:02 ` eijiro_sumii
2000-12-14 21:53 ` Stephan Tolksdorf
2000-12-14 21:12 Ruchira Datta
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