Date: Tue, 30 Sep 2003 13:45:14 -0700 (PDT) From: Maxime Henrion <mux@FreeBSD.org> To: src-committers@FreeBSD.org, cvs-src@FreeBSD.org, cvs-all@FreeBSD.org Subject: cvs commit: src/sys/sys cdefs.h Message-ID: <200309302045.h8UKjE9j021972@repoman.freebsd.org>
next in thread | raw e-mail | index | archive | help
mux 2003/09/30 13:45:14 PDT
FreeBSD src repository
Modified files:
sys/sys cdefs.h
Log:
Introduce new __predict_false(exp) and __predict_true(exp) keywords.
Their purpose is to give explicit hints to the compiler to judge
the likelyhood of a test to succeed or fail. Not all architectures
have support for such optimizations, but for those who do, it can
give a nice performance improvement in hot loops.
Obviously, this should be used very rarely in very specific code.
Reviewed by: peter
Obtained from: OpenBSD
Revision Changes Path
1.77 +36 -0 src/sys/sys/cdefs.h
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?200309302045.h8UKjE9j021972>