Date: Tue, 19 Oct 2010 22:11:50 +0000 (UTC) From: Jilles Tjoelker <jilles@FreeBSD.org> To: cvs-src-old@freebsd.org Subject: cvs commit: src/lib/libc/i386/string Makefile.inc strlen.S Message-ID: <201010192212.o9JMCCD4045078@repoman.freebsd.org>
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jilles 2010-10-19 22:11:50 UTC
FreeBSD src repository
Modified files: (Branch: RELENG_8)
lib/libc/i386/string Makefile.inc
Removed files: (Branch: RELENG_8)
lib/libc/i386/string strlen.S
Log:
SVN rev 214086 on 2010-10-19 22:11:50Z by jilles
MFC r213326: 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.
A simple test on a Phenom II showed the C version, compiled with -O2, to be
about twice as fast determining the length of 100000 strings between 0 and
255 bytes long.
Revision Changes Path
1.13.34.2 +1 -1 src/lib/libc/i386/string/Makefile.inc
1.10.2.2 +0 -54 src/lib/libc/i386/string/strlen.S (dead)
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