return example ASM

addThree:
        push    rbp
        mov     rbp, rsp
        mov     DWORD PTR [rbp-4], edi
        mov     eax, DWORD PTR [rbp-4]
        add     eax, 3
        pop     rbp
        ret
main:
        push    rbp
        mov     rbp, rsp
        sub     rsp, 16
        mov     DWORD PTR [rbp-4], 0
        mov     edi, 2
        call    addThree
        mov     DWORD PTR [rbp-4], eax
        add     DWORD PTR [rbp-4], 5
        mov     eax, 0
        leave
        ret


;Line 9 is where the program begins.
;Line 10, 11, and 12 are just some setup.
;Line 13 is where it initializes "n" to be zero.
;Line 14 moves the integer "2" into the register "edi".
;Line 15 calls "addThree" and the program jumps to executing from line 2.
;Lines 2 and 3 are just some setup.
;Lines 4 and 5 are just moving the value from the edi register into the eax register (the value being the integer "2").
;Line 6 then performs an addition operation (value of eax+2) which stores the resulting value in the eax register.
;Line 7 does some cleanup, and then line 8 returns. Now the program jumps down to line 16, right after the call to addThree.
;Line 16 moves the value from eax to somewhere in memory.
;Line 17 performs an addition operation which adds 5 to the value that was returned from addThree.
;Line 18 sets up the zero for the return code, then finally...
;Lines 19 and 20 is the conclusion of our program: termination.