Question

I’m trying to learn about $ra, so the output I want is “mainfunction1main” , by main calling function1, function1 returning to main, and main finishing. but for some reason I’m getting an infinite loop which prints “mainfunction1mainfunction1……” what am I doing wrong?

    .data
mainstring: .asciiz "main"  
string1: .asciiz "function1"
string2: .asciiz "function2"
string3: .asciiz "function3"

.text

main:   la $a0,mainstring
        li $v0, 4
        syscall

        jal function1

        la $a0, mainstring
        syscall

function1: la $a0, string1
            syscall
            jr $ra

Answer 1

Like JasonD said, you need to exit your program at the end of main. All you need to do is append two lines at the end of main, like so:

main:
    # ... previous stuff

    li $v0, 10                                                                                                                                                               
    syscall

This will load and run the exit system call (which has a code of 10.)