Replace BigInt.shift_right with Z.shift_right

tests/regression/40-threadid/12-threads.c

@@ -0,0 +1,50 @@
+
+#include <goblint.h>
+#include <pthread.h>
+
+/* Slab sizing definitions. */
+#define POWER_SMALLEST 1
+#define POWER_LARGEST 16 /* actual cap is 255 */
+#define LARGEST_ID POWER_LARGEST
+/* Locks for cache LRU operations */
+pthread_mutex_t lru_locks[POWER_LARGEST];
+static pthread_t item_crawler_tid;
+
+int myglobal;
+
+void memcached_thread_init(int nthreads, void *arg) {
+    int i;
+    for (i = 0; i < POWER_LARGEST; i++) {
+        pthread_mutex_init(&lru_locks[i], NULL);
+    }
+}
+
+void *item_crawler_thread(void *arg) {
+    int i, r1, r2;
+    for (i = POWER_SMALLEST; i < LARGEST_ID; i++) {
+        pthread_mutex_lock(&lru_locks[i]);
+        myglobal = myglobal + 1; // RACE!
+        if (r1) {
+            pthread_mutex_unlock(&lru_locks[i]);
+            continue;
+        }
+        // if (r2) {
+        //     int x = 0;
+        // }
+    }
+    return NULL;
+}
+
+int main(void) {
+    int i;
+    int num_threads = rand();
+    memcached_thread_init(num_threads, NULL);
+    pthread_create(&item_crawler_tid, NULL, item_crawler_thread, NULL);
+    for (i = POWER_SMALLEST; i < LARGEST_ID; i++) {
+        pthread_mutex_lock(&lru_locks[i]);
+        myglobal = myglobal + 1; // RACE!
+        pthread_mutex_unlock(&lru_locks[i]);
+    }
+    pthread_join(&item_crawler_tid, NULL);
+    return 0;
+}