cpu_relax.h

/**
 * ai-utils -- C++ Core utilities
 *
 * @file
 * @brief Declaration of cpu_relax().
 *
 * @Copyright (C) 2018  Carlo Wood.
 *
 * pub   dsa3072/C155A4EEE4E527A2 2018-08-16 Carlo Wood (CarloWood on Libera) <carlo@alinoe.com>
 * fingerprint: 8020 B266 6305 EE2F D53E  6827 C155 A4EE E4E5 27A2
 *
 * This file is part of ai-utils.
 *
 * ai-utils 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 3 of the License, or
 * (at your option) any later version.
 *
 * ai-utils 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 ai-utils.  If not, see <http://www.gnu.org/licenses/>.
 */

#pragma once

[[gnu::always_inline]] inline static void cpu_relax()
{
#if defined(__x86_64__) || defined(__i386__)
  asm volatile("pause" ::: "memory");
#elif defined(__aarch64__)
  asm volatile("yield" ::: "memory");
#else
#error "Please extent utils/cpu_relax.h for your architecture."
#endif
}