Test LB+rs

ARM LB+rs () "LB+rs Register shadowing illustration"
{
 P0:R4=x; P1:R4=x; P0:R5=y; P1:R5=y;
 [x] = 0; [y] = 0;
}
   P0          |     P1            ;
ldr R1, R4     | ldr  R3, R5  ;
mov  R2, R1    | add R3, R3, 1  ;
mov  R1, 1     | str  R3, R4  ;
str R1, R5     |                   ;

Observed
    0:R1=1; 0:R2=2; 1:R3=2; x=2; y=1;