/* * Copyright (C) 2019 The DOSBox Team * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License along * with this program; if not, write to the Free Software Foundation, Inc., * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */ #ifndef DOSBOX_COMPILER_H #define DOSBOX_COMPILER_H // This header wraps compiler-specific features, so they won't need to // be hacked into the buildsystem. // GCC_LIKELY macro is incorrectly named, because other compilers support // this feature as well (e.g. Clang, Intel); leave it be for now, at // least until full support for C++20 [[likely]] attribute will start arriving // in new compilers. // // Note: '!!' trick is used, to convert non-boolean values to 1 or 0 // to prevent accidental incorrect usage (e.g. when user wraps macro // around a pointer or an integer, expecting usual C semantics). #if C_HAS_BUILTIN_EXPECT #define GCC_LIKELY(x) __builtin_expect(!!(x), 1) #define GCC_UNLIKELY(x) __builtin_expect(!!(x), 0) #else #define GCC_LIKELY #define GCC_UNLIKELY #endif #endif /* DOSBOX_COMPILER_H */