test: insanesync: convert to C++

[model-checker.git] / test / insanesync.cc

diff --git a/test/insanesync.cc b/test/insanesync.cc
new file mode 100644 (file)
index 0000000..57c610e
--- /dev/null
+++ b/test/insanesync.cc
@@ -0,0 +1,71 @@
+#include <stdlib.h>
+#include <stdio.h>
+#include <threads.h>
+#include <atomic>
+
+#include "librace.h"
+#include "model-assert.h"
+
+using namespace std;
+
+atomic_int x;
+atomic_int y;
+atomic_intptr_t z;
+atomic_intptr_t z2;
+
+int r1, r2, r3; /* "local" variables */
+
+/**
+               This example illustrates a self-satisfying cycle involving
+               synchronization.  A failed synchronization creates the store that
+               causes the synchronization to fail.
+
+               The C++11 memory model nominally allows r1=0, r2=1, r3=5.
+
+               This example is insane, we don't support that behavior.
+*/
+
+
+static void a(void *obj)
+{
+       z.store((intptr_t)&y, memory_order_relaxed);
+       r1 = y.fetch_add(1, memory_order_release);
+       z.store((intptr_t)&x, memory_order_relaxed);
+       r2 = y.fetch_add(1, memory_order_release);
+}
+
+
+static void b(void *obj)
+{
+       r3 = y.fetch_add(1, memory_order_acquire);
+       void *ptr = (void *)z.load(memory_order_relaxed);
+       z2.store((intptr_t)ptr, memory_order_relaxed);
+}
+
+static void c(void *obj)
+{
+       atomic_int *ptr2 = (atomic_int *)z2.load(memory_order_relaxed);
+       (*ptr2).store(5, memory_order_relaxed);
+}
+
+int user_main(int argc, char **argv)
+{
+       thrd_t t1, t2, t3;
+
+       atomic_init(&x, 0);
+       atomic_init(&y, 0);
+       atomic_init(&z, (intptr_t) &x);
+       atomic_init(&z2, (intptr_t) &x);
+
+       thrd_create(&t1, (thrd_start_t)&a, NULL);
+       thrd_create(&t2, (thrd_start_t)&b, NULL);
+       thrd_create(&t3, (thrd_start_t)&c, NULL);
+
+       thrd_join(t1);
+       thrd_join(t2);
+       thrd_join(t3);
+
+       printf("r1=%d, r2=%d, r3=%d\n", r1, r2, r3);
+
+       return 0;
+}