| //===-- Definition of type which can represent a futex word ---------------===// |
| // |
| // 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_TYPES_FUTEX_WORD_H__ |
| #define __LLVM_LIBC_TYPES_FUTEX_WORD_H__ |
| |
| typedef struct { |
| #if defined(__unix__) && (defined(__x86_64__) || defined(__aarch64__)) |
| // Futex word should be aligned appropriately to allow target atomic |
| // instructions. This declaration mimics the internal setup. |
| _Alignas(sizeof(unsigned int) > _Alignof(unsigned int) |
| ? sizeof(unsigned int) |
| : _Alignof(unsigned int)) unsigned int __word; |
| _Static_assert(sizeof(unsigned int) == 4, "Unexpected size of unsigned int."); |
| #else |
| #error "A type to represent a futex word is not available for the target arch." |
| #endif |
| } __futex_word; |
| |
| #endif // __LLVM_LIBC_TYPES_FUTEX_WORD_H__ |
