#include <pthread.h>
#include <stdio.h>
#include <unistd.h>
const int kTestCount = 4;
typedef long long T;
T atomics[kTestCount * 2];
void Test(int test, T *p, bool main_thread) {
volatile T sink;
if (test == 0) {
if (main_thread)
__atomic_fetch_add(p, 1, __ATOMIC_RELAXED);
else
__atomic_fetch_add(p, 1, __ATOMIC_RELAXED);
} else if (test == 1) {
if (main_thread)
__atomic_exchange_n(p, 1, __ATOMIC_ACQ_REL);
else
__atomic_exchange_n(p, 1, __ATOMIC_ACQ_REL);
} else if (test == 2) {
if (main_thread)
sink = __atomic_load_n(p, __ATOMIC_SEQ_CST);
else
__atomic_store_n(p, 1, __ATOMIC_SEQ_CST);
} else if (test == 3) {
if (main_thread)
sink = __atomic_load_n(p, __ATOMIC_SEQ_CST);
else
sink = *p;
}
}
void *Thread(void *p) {
for (int i = 0; i < kTestCount; i++) {
Test(i, &atomics[i], false);
}
sleep(2);
for (int i = 0; i < kTestCount; i++) {
fprintf(stderr, "Test %d reverse\n", i);
Test(i, &atomics[kTestCount + i], false);
}
return 0;
}
int main() {
pthread_t t;
pthread_create(&t, 0, Thread, 0);
sleep(1);
for (int i = 0; i < kTestCount; i++) {
fprintf(stderr, "Test %d\n", i);
Test(i, &atomics[i], true);
}
for (int i = 0; i < kTestCount; i++) {
Test(i, &atomics[kTestCount + i], true);
}
pthread_join(t, 0);
}