[utest][cpp]add cpp-atomic testcase.

Author: Rbb666

examples/utest/testcases/cpp11/tc_atomic.cpp

@@ -0,0 +1,271 @@
+/*
+ * Copyright (c) 2006-2025, RT-Thread Development Team
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * Change Logs:
+ * Date           Author       Notes
+ * 2025-09-19     Rbb666       the first version
+ */
+
+#include <rtthread.h>
+#include "utest.h"
+#include <thread>
+#include <atomic>
+#include <cstdint>
+
+/**
+ * @brief Test load and store operations for int32_t atomic variables in multi-threaded environment.
+ *        Verifies atomicity by performing increment and decrement operations concurrently.
+ */
+static void test_atomic_load_store_int32(void)
+{
+    constexpr int        kRound = 10000000;
+    std::atomic<int32_t> thread_count(0);
+    std::atomic<int32_t> count(100);
+    uassert_int_equal(count.load(), 100);
+
+    auto func1 = [&]() mutable {
+        for (int i = 0; i < kRound; ++i)
+        {
+            ++count;
+        }
+        ++thread_count;
+    };
+
+    auto func2 = [&]() mutable {
+        for (int i = 0; i < kRound; ++i)
+        {
+            --count;
+        }
+        ++thread_count;
+    };
+
+    std::thread t1(func1);
+    std::thread t2(func2);
+    t1.join();
+    t2.join();
+
+    uassert_int_equal(count.load(), 100);
+    uassert_int_equal(thread_count.load(), 2);
+}
+
+/**
+ * @brief Test load and store operations for int64_t atomic variables in multi-threaded environment.
+ *        Verifies atomicity by performing increment and decrement operations concurrently.
+ */
+static void test_atomic_load_store_int64(void)
+{
+    constexpr int        kRound = 10000000;
+    std::atomic<int64_t> thread_count(0);
+    std::atomic<int64_t> count(100);
+    uassert_int_equal(count.load(), 100);
+
+    auto func1 = [&]() mutable {
+        for (int i = 0; i < kRound; ++i)
+        {
+            ++count;
+        }
+        ++thread_count;
+    };
+
+    auto func2 = [&]() mutable {
+        for (int i = 0; i < kRound; ++i)
+        {
+            --count;
+        }
+        ++thread_count;
+    };
+
+    std::thread t1(func1);
+    std::thread t2(func2);
+    t1.join();
+    t2.join();
+
+    uassert_int_equal(count.load(), 100);
+    uassert_int_equal(thread_count.load(), 2);
+}
+
+/**
+ * @brief Test basic atomic operations for int32_t, including load, store, fetch_add, fetch_sub,
+ *        fetch_and, fetch_or, fetch_xor, exchange, and compare_exchange_strong.
+ */
+static void test_atomic_basic_int32(void)
+{
+    std::atomic<int32_t> val;
+    val = 10;
+    uassert_int_equal(val.load(), 10);
+
+    val++;
+    uassert_int_equal(val.load(), 11);
+
+    val--;
+    uassert_int_equal(val.load(), 10);
+
+    auto a = val.load();
+    val.store(a);
+    val.fetch_add(1);
+    uassert_int_equal(val.load(), 11);
+    val.fetch_sub(1);
+    uassert_int_equal(val.load(), 10);
+
+    val.fetch_and(14);
+    uassert_int_equal(val.load(), 10);
+
+    val.fetch_or(11); //1010
+    uassert_int_equal(val.load(), 11);
+
+    val.fetch_xor(4);
+    uassert_int_equal(val.load(), 15);
+
+    val.exchange(1);
+    uassert_int_equal(val.load(), 1);
+
+    int32_t x         = 2;
+    int32_t y         = 3;
+    bool    exchanged = val.compare_exchange_strong(x, y);
+    uassert_false(exchanged);
+    uassert_int_equal(val.load(), 1);
+    uassert_int_equal(x, 1);
+    exchanged = val.compare_exchange_strong(x, y);
+    uassert_true(exchanged);
+    uassert_int_equal(val.load(), 3);
+    uassert_int_equal(x, 1);
+}
+
+/**
+ * @brief Test basic atomic operations for int64_t, including load, store, fetch_add, fetch_sub,
+ *        fetch_and, fetch_or, fetch_xor, exchange, and compare_exchange_strong.
+ */
+static void test_atomic_basic_int64(void)
+{
+    std::atomic<int64_t> val;
+    val = 10;
+    uassert_int_equal(val.load(), 10);
+
+    val++;
+    uassert_int_equal(val.load(), 11);
+
+    val--;
+    uassert_int_equal(val.load(), 10);
+
+    auto a = val.load();
+    val.store(a);
+    val.fetch_add(1);
+    uassert_int_equal(val.load(), 11);
+    val.fetch_sub(1);
+    uassert_int_equal(val.load(), 10);
+
+    val.fetch_and(14);
+    uassert_int_equal(val.load(), 10);
+
+    val.fetch_or(11); //1010
+    uassert_int_equal(val.load(), 11);
+
+    val.fetch_xor(4);
+    uassert_int_equal(val.load(), 15);
+
+    val.exchange(1);
+    uassert_int_equal(val.load(), 1);
+
+    int64_t x         = 2;
+    int64_t y         = 3;
+    bool    exchanged = val.compare_exchange_strong(x, y);
+    uassert_false(exchanged);
+    uassert_int_equal(val.load(), 1);
+    uassert_int_equal(x, 1);
+    exchanged = val.compare_exchange_strong(x, y);
+    uassert_true(exchanged);
+    uassert_int_equal(val.load(), 3);
+    uassert_int_equal(x, 1);
+}
+
+/**
+ * @brief Test atomic operations for bool type, including store, load, exchange, and compare_exchange_strong.
+ */
+static void test_atomic_bool(void)
+{
+    std::atomic<bool> flag(false);
+    flag.store(true);
+    uassert_true(flag.load());
+    flag.exchange(false);
+    uassert_false(flag.load());
+    bool expected = false;
+    bool desired  = true;
+    uassert_true(flag.compare_exchange_strong(expected, desired));
+    uassert_true(flag.load());
+}
+
+/**
+ * @brief Test atomic operations for pointer type (int*), including store, load, and exchange.
+ */
+static void test_atomic_pointer(void)
+{
+    int                a = 1, b = 2;
+    std::atomic<int *> ptr(&a);
+    ptr.store(&b);
+    uassert_int_equal(*ptr.load(), 2);
+    int *old = ptr.exchange(&a);
+    uassert_ptr_equal(old, &b);
+    uassert_int_equal(*ptr.load(), 1);
+}
+
+/**
+ * @brief Test memory ordering constraints using memory_order_release and memory_order_acquire.
+ */
+static void test_memory_order(void)
+{
+    std::atomic<int> x(0);
+    std::atomic<int> y(0);
+    // Simple test for memory order
+    x.store(1, std::memory_order_release);
+    y.store(2, std::memory_order_release);
+    uassert_int_equal(x.load(std::memory_order_acquire), 1);
+    uassert_int_equal(y.load(std::memory_order_acquire), 2);
+}
+
+/**
+ * @brief Test compare_exchange_weak operation, which may fail spuriously and requires looping.
+ */
+static void test_compare_exchange_weak(void)
+{
+    std::atomic<int> val(1);
+    int              expected = 1;
+    int              desired  = 2;
+    while (!val.compare_exchange_weak(expected, desired))
+    {
+        expected = 1; // reset
+    }
+    uassert_int_equal(val.load(), 2);
+}
+
+static rt_err_t utest_tc_init(void)
+{
+    return RT_EOK;
+}
+
+static rt_err_t utest_tc_cleanup(void)
+{
+    return RT_EOK;
+}
+
+static void testcase(void)
+{
+    /* Test load and store operations for int32_t atomic variables in multi-threaded environment */
+    UTEST_UNIT_RUN(test_atomic_load_store_int32);
+    /* Test load and store operations for int64_t atomic variables in multi-threaded environment */
+    UTEST_UNIT_RUN(test_atomic_load_store_int64);
+    /* Test basic atomic operations for int32_t */
+    UTEST_UNIT_RUN(test_atomic_basic_int32);
+    /* Test basic atomic operations for int64_t */
+    UTEST_UNIT_RUN(test_atomic_basic_int64);
+    /* Test atomic operations for bool type */
+    UTEST_UNIT_RUN(test_atomic_bool);
+    /* Test atomic operations for pointer type */
+    UTEST_UNIT_RUN(test_atomic_pointer);
+    /* Test memory ordering constraints */
+    UTEST_UNIT_RUN(test_memory_order);
+    /* Test compare_exchange_weak operation */
+    UTEST_UNIT_RUN(test_compare_exchange_weak);
+}
+UTEST_TC_EXPORT(testcase, "testcases.cpp11.atomic_tc", utest_tc_init, utest_tc_cleanup, 10);