Cheat Engine

です · Newbie cheater Reputation: 0 Joined: 09 Feb 2008 Posts: 20

I searched around the forums, also checked Wikipedia and various documentations for x86 assembly... but I couldn't find anything on what I want to do.

In CE, I want to use registersymbol to register a function that I want to be able to call from anywhere. The function is basically a very simple custom division (which works perfectly, btw) without remainders or float support.

The way I'm using it is:

Dark Byte · Posted: Sat Feb 23, 2008 6:19 pm Post subject:

there are 2 things that I don't get

1:
2 pushes, 3 pops ?

2:
What type of parametertype does DivisionMain use (stdcall, or registers?)
if stdcall, the 2 pushes will be poped off by the DivisionMain
if registers the push isn't even needed, unless you just wanted to save the value, in which case, why the 3th pop ?

if c-decl, then the pushes will not be popped off by DivisionMain and you have to pop them off yourself. But again, why the 3th pop ?

です · Newbie cheater Reputation: 0 Joined: 09 Feb 2008 Posts: 20

Since ecx is the answer to the division, DivisionMain pushes it. Also, I'm just using registers as parameters (I guess?).

Basically, it works like this:

push eax //number to divide
push ebx //number to divide eax by
call DivisionMain
...
// now inside of DivisionMain:
push ecx // answer, which is the result of division behind the scenes, which returns the right value
...
ret
...
// what ret SHOULD return to:
-do stuff with ecx here-
pop eax
pop ebx
pop ecx

If I absolutely have to post more of the division code I will, but I'm perfectly sure that there's no errors in it.

EDIT: Maybe the problem is the way I'm doing it. I have an auto-assemble script that injects the division function and registers a symbol. Then, I have another auto-assemble script that triggers when I fire a shot, which is the code that you see calling DivisionMain.

EDIT2: (not sure if I can double post to just say it's resolved, so I'll just edit)

It seems I didn't completely understand how it worked. I thought that each register had it's own stack so I could just push and pop whenever I wanted. It must have been returning to 0 because I had pushed ecx (usually at 0) to the top of the stack, when ret would pop the value on the top and return to it. So stupidity on my part.