C dep+plain (* * Result: Never * * This litmus test demonstrates that in LKMM, plain accesses * carry dependencies much like accesses to registers: * The data stored to *z1 and *z2 by P0() originates from P0()'s * READ_ONCE(), and therefore using that data to compute the * conditional of P0()'s if-statement creates a control dependency * from that READ_ONCE() to P0()'s WRITE_ONCE(). *) {} P0(int *x, int *y, int *z1, int *z2) { int a = READ_ONCE(*x); *z1 = a; *z2 = *z1; if (*z2 == 1) WRITE_ONCE(*y, 1); } P1(int *x, int *y) { int r = smp_load_acquire(y); smp_store_release(x, r); } exists (x=1 /\ y=1)