C C-IRIW+o+o+o-mb-o+o-mb-o.litmus

{
}

P0(int *x)
{
	WRITE_ONCE(*x, 1);
}

P1(int *y)
{
	WRITE_ONCE(*y, 1);
}

P2(int *x, int *y)
{
	int r1;
	int r2;

	r1 = READ_ONCE(*x);
	smp_mb();
	r2 = READ_ONCE(*y);
}

P3(int *x, int *y)
{
	int r1;
	int r2;

	r1 = READ_ONCE(*y);
	smp_mb();
	r2 = READ_ONCE(*x);
}

exists
(2:r1=1 /\ 2:r2=0 /\ 3:r1=1 /\ 3:r2=0)