Test C11-D

AArch64 C11-D
"Fourth example from notes41"
{
0:X1=x; 0:X3=y;
1:X1=y; 1:X3=x;
}
 P0           | P1           ;
 MOV W0,#2    | MOV W0,#2    ;
 STLR W0,[X1] | STLR W0,[X1] ;
 MOV W2,#1    | MOV W2,#1    ;
 STR W2,[X3]  | STR W2,[X3]  ;
 LDAR W9,[X3] | LDAR W9,[X3] ;
exists
(x=2 /\ y=2 /\ 0:X9=1 /\ 1:X9=1)