Date: Tue, 3 Jan 2012 16:52:21 +0100 From: Pawel Jakub Dawidek <pjd@FreeBSD.org> To: Ed Schouten <ed@FreeBSD.org> Cc: svn-src-head@freebsd.org, svn-src-all@freebsd.org, src-committers@freebsd.org Subject: Re: svn commit: r229198 - in head: share/man/man9 sys/conf sys/libkern sys/sys Message-ID: <20120103155221.GB1663@garage.freebsd.pl> In-Reply-To: <201201012026.q01KQBS5029156@svn.freebsd.org> References: <201201012026.q01KQBS5029156@svn.freebsd.org>
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--yEPQxsgoJgBvi8ip Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Sun, Jan 01, 2012 at 08:26:11PM +0000, Ed Schouten wrote: > Author: ed > Date: Sun Jan 1 20:26:11 2012 > New Revision: 229198 > URL: http://svn.freebsd.org/changeset/base/229198 >=20 > Log: > Introducing memcchr(3). > =20 > It seems two of the file system drivers we have in the tree, namely ufs > and ext3, use a function called `skpc()'. The meaning of this function > does not seem to be documented in FreeBSD, but it turns out one needs to > be a VAX programmer to understand what it does. > =20 > SPKC is an instruction on the VAX that does the opposite of memchr(). It > searches for the non-equal character. Add a new function called > memcchr() to the tree that has the following advantages over skpc(): > =20 > - It has a name that makes more sense than skpc(). Just like strcspn() > matches the complement of strspn(), memcchr() is the complement of > memchr(). > =20 > - It is faster than skpc(). Similar to our strlen() in libc, it compares > entire words, instead of single bytes. It seems that for this routine > this yields a sixfold performance increase on amd64. > =20 > - It has a man page. >=20 > Added: > head/share/man/man9/memcchr.3 (contents, props changed) Shouldn't this be memcchr.9? --=20 Pawel Jakub Dawidek http://www.wheelsystems.com FreeBSD committer http://www.FreeBSD.org Am I Evil? Yes, I Am! http://yomoli.com --yEPQxsgoJgBvi8ip Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.14 (FreeBSD) iEYEARECAAYFAk8DJDUACgkQForvXbEpPzSUlgCfRU8b0la4rX2k3GmkU+uBsj5q 14UAoLti0y6TJbXigPmK7JWM6Xu4V28Z =Czu1 -----END PGP SIGNATURE----- --yEPQxsgoJgBvi8ip--
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