Test SB+mbs

C SB+o-mb-o+o-mb-o
Hash=664109a9d0f37cc80d331a1ae22a0a3f

{x=0; y=0;}


P0(int* x,int* y) {
  WRITE_ONCE(*x,1);
  smp_mb();
  int r2 = READ_ONCE(*y);
}

P1(int* x,int* y) {
  WRITE_ONCE(*y,1);
  smp_mb();
  int r4 = READ_ONCE(*x);
}

exists (0:r2=0 /\ 1:r4=0)

C11 equivalent: c11-prop-src/sb+o-mb-o+o-mb-o.litmus