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;playing with the stack
section .data
arg db 255
section .text
global _start
uhh:
; save stack
push ebp
; create local stack
mov ebp, esp
; create "local" variable(s) by subtracting the stack by X bytes
sub ebp, 4
; first argument is 3 dwords (4 bytes * 3) in...
; copy first argument to eax
mov eax, [ebp+12]
; mov eax (first arg) into local stack variable
mov [ebp-4], eax
; clear eax
mov eax, 0
; mov local variable into ebx
mov ebx, [ebp-4]
; reset stack pointer
; aka, giveth back what we taketh away
add ebp, 4
; restore stack
mov esp, ebp
pop ebp
ret
_start:
; save stack
push ebp
mov ebp, esp
; push value of 'arg' to the stack from ebx
mov ebx, [arg]
push ebx
; clear ebx
mov ebx, 0
call uhh
; restore ebx (because I can.) should be value of 'arg'
pop ebx
; restore stack
mov esp, ebp
pop ebp
; exit program, ebx is return value
mov eax, 1
int 80h
ret
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