| //===-- Utilities for suspending threads ----------------------------------===// |
| // |
| // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
| // See https://llvm.org/LICENSE.txt for license information. |
| // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #ifndef LLVM_LIBC_SRC___SUPPORT_THREADS_SLEEP_H |
| #define LLVM_LIBC_SRC___SUPPORT_THREADS_SLEEP_H |
| |
| #include "src/__support/macros/attributes.h" |
| |
| namespace LIBC_NAMESPACE { |
| |
| /// Suspend the thread briefly to assist the thread scheduler during busy loops. |
| LIBC_INLINE void sleep_briefly() { |
| #if defined(LIBC_TARGET_ARCH_IS_NVPTX) |
| if (__nvvm_reflect("__CUDA_ARCH") >= 700) |
| LIBC_INLINE_ASM("nanosleep.u32 64;" ::: "memory"); |
| #elif defined(LIBC_TARGET_ARCH_IS_AMDGPU) |
| __builtin_amdgcn_s_sleep(2); |
| #elif defined(LIBC_TARGET_ARCH_IS_X86) |
| __builtin_ia32_pause(); |
| #elif defined(LIBC_TARGET_ARCH_IS_AARCH64) |
| __builtin_arm_isb(0xf); |
| #else |
| // Simply do nothing if sleeping isn't supported on this platform. |
| #endif |
| } |
| |
| } // namespace LIBC_NAMESPACE |
| |
| #endif // LLVM_LIBC_SRC___SUPPORT_THREADS_SLEEP_H |
