Test safe011

PPC safe011
"SyncdWW Rfe DpdW Wse"
Cycle=SyncdWW Rfe DpdW Wse
Relax=
Safe=Wse DpdW BCSyncdWW
{
0:r2=x; 0:r5=y;
1:r2=y; 1:r4=x;
}
 P0            | P1           ;
 lwz r1,0(r2)  | li r1,2      ;
 xor r3,r1,r1  | stw r1,0(r2) ;
 li r4,1       | sync         ;
 stwx r4,r3,r5 | li r3,1      ;
               | stw r3,0(r4) ;
exists
(y=2 /\ 0:r1=1)