mfbt/Likely.h
author Gregory Szorc <gps@mozilla.com>
Wed, 28 Jan 2015 13:37:00 -0800
branchGECKO140_2012062401_RELBRANCH
changeset 120204 49838761146e772650e6739254d82541b76d2540
parent 92606 17c65d32c7b891e70435561b965b71c355bd28ac
child 100672 1a0f4431003105008d31616e75b8db2d3291d54f
permissions -rw-r--r--
Close old release branch GECKO140_2012062401_RELBRANCH

/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this file,
 * You can obtain one at http://mozilla.org/MPL/2.0/. */

/*
 * MOZ_LIKELY and MOZ_UNLIKELY macros to hint to the compiler how a
 * boolean predicate should be branch-predicted.
 */

#ifndef Likely_h_
#define Likely_h_

#if defined(__clang__) || (defined(__GNUC__) && (__GNUC__ > 2))
#  define MOZ_LIKELY(x)   (__builtin_expect((x), 1))
#  define MOZ_UNLIKELY(x) (__builtin_expect((x), 0))
#else
#  define MOZ_LIKELY(x)   (x)
#  define MOZ_UNLIKELY(x) (x)
#endif

#endif /* Likely_h_ */