How do I reverse an array in place in assembly?

I am supposed to reverse an array in place. I have been working on it for a while and this is what I have. Can anyone tell me w开发者_Python百科hat I'm doing wrong?

.data
array BYTE 10h, 20h, 30h, 40h

.code
main PROC
    mov esi, 0
    mov edi, 0
    mov esi, OFFSET array
    mov edi, OFFSET array + SIZEOF array
    mov ecx, SIZEOF array/2

l1: mov al, [esi]
    mov bl, [edi]
    mov [edi], al
    mov [esi], bl
    inc esi
    dec edi
    LOOP l1

    call DumpRegs
    call DumpMem

    exit

main ENDP

END main

---

Try to declare two arrays, one intilized with your values and the other one could be like this using DUP operator 5 DUP (?)

And start moving values from first array to the second using a loop.

Example:

.data myArr1 DWORD 5, 4, 3, 2, 1 myArr2 DWORD 5 DUP (?)

.code main proc mov edi, offset myArr1 add edi, sizeof myArr1 mov esi, offset myArr2 mov ecx, lengthof myArr2

reverseLoop: add ebx, [edi] mov[edi], ebx sub edi, type myArr2 add esi, type myArr1 mov eax, [edi] call writeint

LOOP reverseLoop

exit main endp end main