Test i2

PPC i2 (ITwo)
"RR reordering w. B-cumul barrier, iwp2.1"

{0:r5=x; 0:r6=y; 0:r1=0; 0:r2=0;
 1:r5=x; 1:r6=y; 1:r3=0; 1:r4=0;
 x=0; y=0;}

P0           | P1           ;
li r1,1      | lwz r3,0(r6) ; 
stw r1,0(r5) | lwz r4,0(r5) ;
sync         |              ;
li r2,1      |              ;
stw r2,0(r6) |              ;
             |              ;

locations [1:r3;1:r4;]

exists(1:r3=1 /\ 1:r4=0)