Test MP+lwsync+addr-BIS

PPC MP+lwsync+addr-BIS
"Variation on MP+lwsync+addr: Fr to a store in program"
{
0:r2=x; 0:r4=y;
1:r2=y; 1:r5=x;
2:r2=x;
}
 P0           | P1            | P2           ;
 li r1,2      | lwz r1,0(r2)  | li r1,1      ;
 stw r1,0(r2) | xor r3,r1,r1  | stw r1,0(r2) ;
 lwsync       | lwzx r4,r3,r5 |              ;
 li r3,1      |               |              ;
 stw r3,0(r4) |               |              ;
exists
(x=2 /\ 1:r1=1 /\ 1:r4=1)