mfbt/Likely.h
author David Anderson <danderson@mozilla.com>
Wed, 29 Aug 2012 17:57:37 -0700
changeset 110338 7bf95bb092331b1db96ba9d561400fcdfb9f09d6
parent 98587 1a0f4431003105008d31616e75b8db2d3291d54f
child 111181 6a2d1a3556b94d4bac0d0283dfe6152110d7af79
permissions -rw-r--r--
Merge from mozilla-central.

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* 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 mozilla_Likely_h_
#define mozilla_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 /* mozilla_Likely_h_ */