Test co7

PPC co7 (PPCCoSeven)
"Coherence tests, fr as ppo (+ pppo-ext)"
{
0:r6=x; 0:r7=y;
1:r6=x; 1:r7=y;
}
P0           |P1           ;
lwz r1,0(r7) |lwz r1,0(r6) ;
xor r9,r1,r1 |xor r9,r1,r1 ;
lwzx r2,r9,r6|lwzx r2,r9,r7;
li r3,1      |li r3,1      ;
stw r3,0(r6) |stw r3,0(r7) ;
locations
[0:r1; 0:r2; 1:r1; 1:r2;]
~exists
(0:r1=1 /\ 0:r2=0 /\ 1:r1=1 /\ 1:r2=0)