Test dx5

PPC dx5 (BasicDXFive)
"Simple sync test, no syncs"
{
 0:r1=1; 0:r4=x; 0:r5=y;
 1:r1=1; 1:r4=x; 1:r5=y;
 2:r2=2; 2:r5=y ;
}

P0             | P1            |P2             ;
lwz r2,0(r5)   | lwz r2,0(r4)  |stw r2,0(r5)   ;
sync           |xor r9,r2,r2   |               ;
stw r1,0(r4)   |stwx r1,r9,r5  |               ;


exists (0:r2=2 /\ 1:r2=1 /\ y=2)