Test n1s

PPC n1s  (PPCNOneSync)
"not exactly iriw, sync barriers"
{
P0:r4=x ; P0:r5=y ;
P1:r4=x ; P1:r5=y ;
P2:r4=x ; P2:r5=y ;
P3:r4=x ; P3:r5=y ;
P2:r1=1 ; P2:r2=4 ;
P3:r2=2 ; P3:r1=3 ;
}

P0           |P1           |P2           |P3           ;
lwz r1,0(r4) |lwz r1,0(r4) |stw r2,0(r5) |stw r2,0(r5) ;
sync         |sync         |sync         |sync         ;
lwz r2,0(r5) |lwz r2,0(r5) |stw r1,0(r4) |stw r1,0(r4) ;
locations [x; y; 0:r1; 0:r2; 1:r1; 1:r2;]