38 lines · cpp
1//===----------------------------------------------------------------------===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8 9// REQUIRES: clang10 11// Adding "-fsanitize=thread" directly causes many platforms to fail (because12// they don't support tsan), and causes other sanitizer builds to fail (e.g.13// asan and tsan don't mix). Instead, require the tsan feature.14// REQUIRES: tsan15 16// This test verifies behavior specified by [atomics.types.operations.req]/21:17//18// When only one memory_order argument is supplied, the value of success is19// order, and the value of failure is order except that a value of20// memory_order_acq_rel shall be replaced by the value memory_order_acquire21// and a value of memory_order_release shall be replaced by the value22// memory_order_relaxed.23//24// This test mirrors replace_failure_order.pass.cpp. However, we also want to25// verify the codegen is correct. This verifies a bug where memory_order_acq_rel26// was not being replaced with memory_order_acquire in external27// TSAN-instrumented tests.28 29// RUN: %{cxx} -c %s %{flags} %{compile_flags} -O2 -stdlib=libc++ -S -emit-llvm -o %t.ll30 31#include <atomic>32 33// Note: libc++ tests do not use on FileCheck.34// RUN: grep -E "call i32 @__tsan_atomic32_compare_exchange_val\(.*, i32 1, i32 4, i32 2\)" %t.ll35bool strong_memory_order_acq_rel(std::atomic<int>* a, int cmp) {36 return a->compare_exchange_strong(cmp, 1, std::memory_order_acq_rel);37}38