> For the complete documentation index, see [llms.txt](https://alham-rizvi.gitbook.io/alhamrizvi/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://alham-rizvi.gitbook.io/alhamrizvi/picoctf-writeups/picoctf/reverse-engineering/bit-o-asm-3.md).

# Bit-O-Asm-3

### Bit-O-Asm-3 — PicoCTF Walkthrough (Reverse Engineering)

Now the function actually does a small calculation. Still, the approach is the same: follow what happens to **EAX**.

The inputs (`edi`, `rsi`) are stored but never used again. The real logic starts with two constants:

```asm
mov DWORD PTR [rbp-0xc], 0x9fe1a
mov DWORD PTR [rbp-0x8], 0x4
```

So:

* `var_c = 0x9fe1a` → 654,874
* `var_8 = 4`

Next, the value is loaded into `EAX` and multiplied:

```asm
mov eax, DWORD PTR [rbp-0xc]
imul eax, DWORD PTR [rbp-0x8]
```

This gives:

```
654,874 × 4 = 2,619,496
```

Then a constant is added:

```asm
add eax, 0x1f5
```

Since:

```
0x1f5 = 501
```

Final calculation:

```
2,619,496 + 501 = 2,619,997
```

That value is returned via `EAX`.

***

### Final Answer

```
2619997
```


---

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