Test RSDWI

PPC RSDWI
{
0:r2=x; 0:r4=y;
1:r2=y; 1:r5=z; 1:r9=x;
2:r2=z;
}
 P0           | P1            | P2           ;
              | li r10,1      |              ;
              | stw r10,0(r5) |              ;
 li r1,1      | lwz r1,0(r2)  | li r1,2      ;
 stw r1,0(r2) | xor r3,r1,r1  | stw r1,0(r2) ;
 lwsync       | lwzx r4,r3,r5 |              ;
 li r3,1      | lwz r6,0(r5)  |              ;
 stw r3,0(r4) | xor r7,r6,r6  |              ;
              | lwzx r8,r7,r9 |              ;
Observed
    1:r1=0; 1:r4=1; 1:r6=2; 1:r8=0; z=2;
and 1:r1=1; 1:r4=2; 1:r6=2; 1:r8=0; z=2;