Test ccv3

PPC ccv3 (CCThree)
"Boehm/adve CC example (Fig.8), sync"
{
0:r1=1 ; 0:r5=x;
1:r5=x ; 1:r6=y;
2:r5=x ; 2:r6=y; 2:r1=1; 2:r2=2;
3:r5=x ;
}
P0          |P1          |P2          |P3          ;
stw r1,0(r5)|lwz r1,0(r5)|stw r1,0(r6)|lwz r1,0(r5);
            |sync        |sync        |            ;
            |lwz r2,0(r6)|stw r2,0(r5)|lwz r2,0(r5);

(*
  May not be seq consistent.
*)
locations [x;]
~exists 
(1:r1=1 /\ 1:r2=0 /\ 3:r1=2 /\ 3:r2=1)
(*
Observed (doko)
(1:r1=1 /\ 1:r2=0 /\ 3:r1=0 /\ 3:r2=0 /\ x=1)
(* ws;rf/fr *)
*)