3Write in ARM assembly language the following operations wit

3.Write in ARM assembly language the following operations without using multiplication instruction (5p.each)
      3.1. A * 17
      3.2. A * 23

Solution

Firstly for A*17, lets do multilpication like A*17 = A*16 + A

mov bx,ax ; save a*1 into b

shl ax,1 ; ax=ax*2

shl ax,1 ; ax = ax*4

shl ax,1 ;ax = ax * 8

shl ax,1 ;ax = ax * 16

add ax,bx ; ax = ax*17

similary for A*23 = A*32 - (A*8+A)

mov bx,ax ; save a*1 into b

shl ax,1 ; ax=ax*2

shl ax,1 ; ax = ax*4

shl ax,1 ;ax = ax * 8

add ax,bx ; ax=ax*9

mov bx,ax ; save ax*9 into bx

shl ax,1 ;a=a*32

sub ax,bx ; ax=ax*32 - ax*9