svn commit: r213326 - head/lib/libc/i386/string
Roman Divacky
rdivacky at FreeBSD.org
Fri Oct 1 13:38:47 UTC 2010
On Fri, Oct 01, 2010 at 01:10:11PM +0000, Jilles Tjoelker wrote:
> Author: jilles
> Date: Fri Oct 1 13:10:11 2010
> New Revision: 213326
> URL: http://svn.freebsd.org/changeset/base/213326
>
> Log:
> libc: Remove the i386 assembler version of strlen(3).
>
> On anything modern, the C version, which processes a word at a time, is much
> faster. The Intel optimization manual explicitly warns against using REP
> prefixes with SCAS or CMPS, which is exactly what the assembler version
> does.
there's "rep cmps" in bcmp.S and memcmp.S in both amd64/i386
they both have C counterparts, no idea how fast those are (they
are going char by char).
does this wisdom apply to those too?
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