//===-- sanitizer_atomic_clang_other.h --------------------------*- C++ -*-===// // // 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 // //===----------------------------------------------------------------------===// // // This file is a part of ThreadSanitizer/AddressSanitizer runtime. // Not intended for direct inclusion. Include sanitizer_atomic.h. // //===----------------------------------------------------------------------===// #ifndef SANITIZER_ATOMIC_CLANG_OTHER_H #define SANITIZER_ATOMIC_CLANG_OTHER_H namespace __sanitizer { inline void proc_yield(int cnt) { __asm__ __volatile__("" ::: "memory"); } template inline typename T::Type atomic_load( const volatile T *a, memory_order mo) { DCHECK(mo & (memory_order_relaxed | memory_order_consume | memory_order_acquire | memory_order_seq_cst)); DCHECK(!((uptr)a % sizeof(*a))); typename T::Type v; if (sizeof(*a) < 8 || sizeof(void*) == 8) { // Assume that aligned loads are atomic. if (mo == memory_order_relaxed) { v = a->val_dont_use; } else if (mo == memory_order_consume) { // Assume that processor respects data dependencies // (and that compiler won't break them). __asm__ __volatile__("" ::: "memory"); v = a->val_dont_use; __asm__ __volatile__("" ::: "memory"); } else if (mo == memory_order_acquire) { __asm__ __volatile__("" ::: "memory"); v = a->val_dont_use; __sync_synchronize(); } else { // seq_cst // E.g. on POWER we need a hw fence even before the store. __sync_synchronize(); v = a->val_dont_use; __sync_synchronize(); } } else { __atomic_load(const_cast(&a->val_dont_use), &v, __ATOMIC_SEQ_CST); } return v; } template inline void atomic_store(volatile T *a, typename T::Type v, memory_order mo) { DCHECK(mo & (memory_order_relaxed | memory_order_release | memory_order_seq_cst)); DCHECK(!((uptr)a % sizeof(*a))); if (sizeof(*a) < 8 || sizeof(void*) == 8) { // Assume that aligned loads are atomic. if (mo == memory_order_relaxed) { a->val_dont_use = v; } else if (mo == memory_order_release) { __sync_synchronize(); a->val_dont_use = v; __asm__ __volatile__("" ::: "memory"); } else { // seq_cst __sync_synchronize(); a->val_dont_use = v; __sync_synchronize(); } } else { __atomic_store(&a->val_dont_use, &v, __ATOMIC_SEQ_CST); } } } // namespace __sanitizer #endif // #ifndef SANITIZER_ATOMIC_CLANG_OTHER_H