Test LB+isync+data

PPC LB+isync+data
"ISyncdRW Rfe DpDatadW Rfe"
Cycle=Rfe ISyncdRW Rfe DpDatadW
{
0:r2=x; 0:r4=y;
1:r2=y; 1:r4=x;
}
 P0           | P1           ;
 lwz r1,0(r2) | lwz r1,0(r2) ;
 isync        | xor r3,r1,r1 ;
 li r3,1      | addi r3,r3,1 ;
 stw r3,0(r4) | stw r3,0(r4) ;
Observed
    0:r1=1; 1:r1=1;