Test safe336

PPC safe336
"SyncsWW Rfe SyncdRW Rfe DpdR Fre"
Cycle=SyncsWW Rfe SyncdRW Rfe DpdR Fre
Relax=
Safe=Fre DpdR BCSyncsWW BCSyncdRW
{
0:r2=y; 0:r4=x;
1:r2=x; 1:r5=y;
2:r2=y;
}
 P0           | P1            | P2           ;
 lwz r1,0(r2) | lwz r1,0(r2)  | li r1,1      ;
 sync         | xor r3,r1,r1  | stw r1,0(r2) ;
 li r3,1      | lwzx r4,r3,r5 | sync         ;
 stw r3,0(r4) |               | li r3,2      ;
              |               | stw r3,0(r2) ;
exists
(y=2 /\ 0:r1=2 /\ 1:r1=1 /\ 1:r4=0)