1C IRIW+poonceonces+OnceOnce
2
3(*
4 * Result: Sometimes
5 *
6 * Test of independent reads from independent writes with nothing
7 * between each pairs of reads.  In other words, is anything at all
8 * needed to cause two different reading processes to agree on the order
9 * of a pair of writes, where each write is to a different variable by a
10 * different process?
11 *)
12
13{
14	int x;
15	int y;
16}
17
18P0(int *x)
19{
20	WRITE_ONCE(*x, 1);
21}
22
23P1(int *x, int *y)
24{
25	int r0;
26	int r1;
27
28	r0 = READ_ONCE(*x);
29	r1 = READ_ONCE(*y);
30}
31
32P2(int *y)
33{
34	WRITE_ONCE(*y, 1);
35}
36
37P3(int *x, int *y)
38{
39	int r0;
40	int r1;
41
42	r0 = READ_ONCE(*y);
43	r1 = READ_ONCE(*x);
44}
45
46exists (1:r0=1 /\ 1:r1=0 /\ 3:r0=1 /\ 3:r1=0)
47