Test T99-STADD

AArch64 T99-STADD
{
0:X1=x; 0:X3=y;
1:X1=y; 1:X11=x; 1:X5=z;
}
P0           | P1               ;
MOV W0,#1    | LDR W0,[X1]      ;
STR W0,[X1]  | CMP W0,#1        ;
MOV W2,#1    | B.EQ L0          ;
STLR W2,[X3] | L0:              ;
               | STR W21, [X5];
              | STADD W18, [X5];
              | LDAR W26, [X5];
              | LDR W10,[X11]    ;
Observed
    1:X16=0; 1:X10=0; 1:X0=1;