I need to subtract two numbers that the user will input. It is my first time writing in assembly that's why the code might not be at all great but I tried to make it as legible as possible.
Here is my code:
.data # Program data are placed below the .data directive
num1: .word 0 # First integer variable, initialized to 0
num2: .word 0 # Second integer variable, initialized to 0
subs: .word 0 # Variable for storing the sum of the two integers
str: .asciiz "Name: Name Surname\nA.M: Somenumber\n" # Storing string in variable str
str1: .asciiz "Enter first integer: " #
str2: .asciiz "Enter second integer: " #
finalStr: .asciiz "The result of the substraction is " #
.text # Program is placed under the .text directive
main: # Standard label in QtSpim for the main program. It should be always used
li $v0, 4
la $a0, str # Store string
syscall # Use this MIPS command to execute a system call
li $v0, 4
la $a0, str1 # Store string
syscall # Use this MIPS command to execute a system call
li $v0,5 # Read integer
syscall # Invoke the operating system.
li $v0,1 # Print integer
lw $a0,num1 # Load the integer
syscall # Invoke the operating system.
li $v0, 4
la $a0, str2 # Store string
syscall # Use this MIPS command to execute a system call
li $v0,5 # Read integer
syscall # Invoke the operating system.
li $v0,1 # Print integer
lw $a1,num2 # Load the integer
syscall # Invoke the operating system.
sub $s0, $a1, $a0 # Substraction
sw $s0, subs # Store the difference in memory (in variable subs)
la $a0, finalStr # To print a string, first its address should be stored to register $a0
li $v0, 4 # System call value for print_string.
syscall # Use this MIPS command to execute a system call
move $a0, $s0 # To print an integer, it should be first stored to register $a0
li $v0, 1 # System call value for print_int
li $v0,10
syscall
My problem is that I'm not really sure if the input field of code is correct since in console right after I Input it shows a zero and the second input a huge ridiculous number. Also the subtraction doesn't get shown at all.
Here is an example of the console in the last run:
Name: Name Surname
A.M: Somenumber
Enter first integer: 5
0Enter second integer: 10
268501072The result of the substraction is
Any ideas of where the problem might be?