Question

make multiply function with ‘add’ command，

Convert to mips code

Don’t use ‘mult’

Use 'add' multiple times

Get input from key-board and display the result in the console window

Answer 1

.data
prompt1: .asciiz "Please enter the first signed (decimal) integer: "
prompt2: .asciiz "Please enter the second signed (decimal) integer: "
result_msg: .asciiz "The result of these two 16-bit integers\' multiplication is: "
.text
.globl main
main:
li $v0, 4 #print prompt
la $a0, prompt1
syscall

li $v0, 5 #read multiplicand
syscall
move $s0, $v0

li $v0, 4 #print prompt
la $a0, prompt2
syscall

li $v0, 5 #read multiplier
syscall
move $s1, $v0

Mult: ori $t0,$zero,1 #mask
move $s3, $0 #initialize the result register
move $t1, $0

loop: beq $s1, $zero, end #if the multiplier is 0 then finished
and $t1, $t0, $s1 #mask
beq $t1, 1, mult_add   
beq $t1, 0, shift

mult_add: addu $s3, $s3, $s0 #add to get product

shift:
sll $s0, $s0, 1 #shift multiplicand left
srl $s1, $s1, 1 #shift multiplier right

j loop

result: #input the print_string
li $v0, 4
la $a0, result_msg
syscall

exit:
li $v0, 1 #input result
move $a0, $s3
syscall

li $v0, 10 #exit
syscall