From: Zack Weinberg <zack@codesourcery.com>
To: Kevin Atkinson <kevin@atkinson.dhs.org>
Cc: gcc@gcc.gnu.org
Subject: Re: Slow memcmp for aligned strings on Pentium 3
Date: Fri, 04 Apr 2003 08:52:00 -0000 [thread overview]
Message-ID: <87llyq9b0e.fsf@egil.codesourcery.com> (raw)
In-Reply-To: <Pine.LNX.4.44.0304031945240.912-200000@kevin-pc.atkinson.dhs.org> (Kevin Atkinson's message of "Thu, 03 Apr 2003 21:11:04 -0500 (EST)")
Kevin Atkinson <kevin@atkinson.dhs.org> writes:
> I was doing some tests with with memcmp and it seams that gcc 3.2.2 always
> uses cmps, even for aligned strings.
>
> I did some tests and discovered that using cmps was rather slow, compared
> to a simple loop and then a bswap and subtract at the end.
Patches are welcome.
zw
next prev parent reply other threads:[~2003-04-04 3:50 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2003-04-04 6:22 Kevin Atkinson
2003-04-04 8:52 ` Zack Weinberg [this message]
2003-04-04 15:16 ` Kevin Atkinson
2003-04-04 13:18 Roger Sayle
2003-04-04 14:51 ` Kevin Atkinson
2003-04-04 17:08 ` Kevin Atkinson
2003-04-04 18:58 ` Marcel Cox
2003-04-04 19:27 ` Kevin Atkinson
2003-04-04 14:33 Bonzini
2003-04-04 17:13 Jerry Quinn
2003-04-04 17:29 ` Kevin Atkinson
2003-04-06 5:54 ` Jerry Quinn
2003-04-06 22:17 ` Kevin Atkinson
2003-04-07 17:30 ` Jerry Quinn
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