solution exercise 2.3


.global _mac
_mac mv .s A4,A5
mv .s B4,A6
zero .l A4
mvk .s 10,A2
loop: ldw .d *A5++,A0
ldw .d *A6++,A1
nop 4
mpy .m A0,A1,A3
nop
add .l A4,A3,A4
sub .l A2,1,A2
[A2] b .s loop
nop 5
b B11
nop 5