xref: /llvm-project/libc/test/src/__support/CPP/atomic_test.cpp (revision 170467eeab6a6e2834c706cc709652d7da74085d)
111372555SSiva Chandra Reddy //===-- Unittests for Atomic ----------------------------------------------===//
211372555SSiva Chandra Reddy //
311372555SSiva Chandra Reddy // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
411372555SSiva Chandra Reddy // See https://llvm.org/LICENSE.txt for license information.
511372555SSiva Chandra Reddy // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
611372555SSiva Chandra Reddy //
711372555SSiva Chandra Reddy //===----------------------------------------------------------------------===//
811372555SSiva Chandra Reddy 
911372555SSiva Chandra Reddy #include "src/__support/CPP/atomic.h"
10af1315c2SSiva Chandra Reddy #include "test/UnitTest/Test.h"
1111372555SSiva Chandra Reddy 
1211372555SSiva Chandra Reddy // Tests in this file do not test atomicity as it would require using
1311372555SSiva Chandra Reddy // threads, at which point it becomes a chicken and egg problem.
1411372555SSiva Chandra Reddy 
1511372555SSiva Chandra Reddy TEST(LlvmLibcAtomicTest, LoadStore) {
16b6bc9d72SGuillaume Chatelet   LIBC_NAMESPACE::cpp::Atomic<int> aint(123);
17b6bc9d72SGuillaume Chatelet   ASSERT_EQ(aint.load(LIBC_NAMESPACE::cpp::MemoryOrder::RELAXED), 123);
1811372555SSiva Chandra Reddy 
19b6bc9d72SGuillaume Chatelet   aint.store(100, LIBC_NAMESPACE::cpp::MemoryOrder::RELAXED);
20b6bc9d72SGuillaume Chatelet   ASSERT_EQ(aint.load(LIBC_NAMESPACE::cpp::MemoryOrder::RELAXED), 100);
2111372555SSiva Chandra Reddy 
2211372555SSiva Chandra Reddy   aint = 1234; // Equivalent of store
23b6bc9d72SGuillaume Chatelet   ASSERT_EQ(aint.load(LIBC_NAMESPACE::cpp::MemoryOrder::RELAXED), 1234);
2411372555SSiva Chandra Reddy }
2511372555SSiva Chandra Reddy 
2611372555SSiva Chandra Reddy TEST(LlvmLibcAtomicTest, CompareExchangeStrong) {
2711372555SSiva Chandra Reddy   int desired = 123;
28b6bc9d72SGuillaume Chatelet   LIBC_NAMESPACE::cpp::Atomic<int> aint(desired);
2911372555SSiva Chandra Reddy   ASSERT_TRUE(aint.compare_exchange_strong(desired, 100));
30b6bc9d72SGuillaume Chatelet   ASSERT_EQ(aint.load(LIBC_NAMESPACE::cpp::MemoryOrder::RELAXED), 100);
3111372555SSiva Chandra Reddy 
3211372555SSiva Chandra Reddy   ASSERT_FALSE(aint.compare_exchange_strong(desired, 100));
33b6bc9d72SGuillaume Chatelet   ASSERT_EQ(aint.load(LIBC_NAMESPACE::cpp::MemoryOrder::RELAXED), 100);
3411372555SSiva Chandra Reddy }
3539451e45SSchrodinger ZHU Yifan 
36*170467eeSSchrodinger ZHU Yifan struct alignas(void *) TrivialData {
37*170467eeSSchrodinger ZHU Yifan   char a;
38*170467eeSSchrodinger ZHU Yifan   char b;
39*170467eeSSchrodinger ZHU Yifan   char padding[sizeof(void *) - 2];
4039451e45SSchrodinger ZHU Yifan };
4139451e45SSchrodinger ZHU Yifan 
4239451e45SSchrodinger ZHU Yifan TEST(LlvmLibcAtomicTest, TrivialCompositeData) {
43*170467eeSSchrodinger ZHU Yifan   LIBC_NAMESPACE::cpp::Atomic<TrivialData> data({'a', 'b', {}});
44*170467eeSSchrodinger ZHU Yifan   ASSERT_EQ(data.load(LIBC_NAMESPACE::cpp::MemoryOrder::RELAXED).a, 'a');
45*170467eeSSchrodinger ZHU Yifan   ASSERT_EQ(data.load(LIBC_NAMESPACE::cpp::MemoryOrder::RELAXED).b, 'b');
4639451e45SSchrodinger ZHU Yifan 
47*170467eeSSchrodinger ZHU Yifan   auto old = data.exchange({'c', 'd', {}});
48*170467eeSSchrodinger ZHU Yifan   ASSERT_EQ(data.load(LIBC_NAMESPACE::cpp::MemoryOrder::RELAXED).a, 'c');
49*170467eeSSchrodinger ZHU Yifan   ASSERT_EQ(data.load(LIBC_NAMESPACE::cpp::MemoryOrder::RELAXED).b, 'd');
50*170467eeSSchrodinger ZHU Yifan   ASSERT_EQ(old.a, 'a');
51*170467eeSSchrodinger ZHU Yifan   ASSERT_EQ(old.b, 'b');
5239451e45SSchrodinger ZHU Yifan }
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