Test CO-LB

PPC CO-LB

{0:r2=x; 1:r2=x;}

 P0           | P1           ;
 lwz r0,0(r2) | lwz r0,0(r2) ;
 li r1,1      | li r1,2      ;
 stw r1,0(r2) | stw r1,0(r2) ;

exists (0:r0=2 /\ 1:r0=1)