Converting this C++ for loop into assembly language [closed] - c++

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Basically what I am trying to do is convert this block of c++ & assembly into purely assembly, I am a bit confused as to how to conver the for loop and the rest into assembly, if anyone could let me know where I am going wrong that would be great.
This is the original
void encrypt_chars (int length, char EKey) // Encryption Function.
{ char temp_char; // Char temporary store.
for (int i = 0; i < length; i++) // Encrypt characters one at a time.
{
temp_char = OChars [i]; // Orignal Chars.
__asm { // Switch to inline assembly.
push eax
push ecx
movzx ecx,temp_char
push ecx
lea eax,EKey
push eax
call encrypt4 // Call the encryption subroutine
add esp, 8
mov temp_char,al
pop ecx
pop eax
}
EChars [i] = temp_char; // Store encrypted char in the encrypted chars array.
}
return;
Then this is my attempt at convering the c++ parts into assembly which is what I am stuggling with and would appreciate some pointers -
void encrypt_chars(int lengths, char EKey) // Encryption Function.
{
char temp_char;
__asm {
mov dword ptr[i], 0
jmp encrypt_chars
mov eax, dword ptr[i]
add eax, 1
mov dword ptr[i], eax
mov eax, dword ptr[i]
cmp eax, dword ptr[lengths]
jge encrypt_chars
mov eax, dword ptr[i]
mov cl, byte ptr[eax]
mov byte ptr[temp_char], cl
push eax
push ecx
movzx ecx,temp_char
push ecx
lea eax,EKey
push eax
call encrypt4 // Call the encryption subroutine
add esp, 8
mov temp_char,al
pop ecx
pop eax
mov eax, dword ptr[i]
mov cl, byte ptr[temp_char]
mov byte ptr[eax], cl
}
return;

Answer 1

Here is an assembly example of a for loop:
mov R1, #5 ; This is the limit of the loop
mov R0, #0 ; R0 is the loop index, initialize the loop index variable.
loop:
cmp R0, R1 ; Part of the compare expression in for loop.
bge loop_exit;
;
; The statement block for the for loop.
inc R0 ; The increment part of the for loop
b loop ; Loop around to the compare part of the loop.
; First statement after the for loop
loop_exit: