Cheat Engine Forum Index Cheat Engine
The Official Site of Cheat Engine
 
 FAQFAQ   SearchSearch   MemberlistMemberlist   UsergroupsUsergroups   RegisterRegister 
 ProfileProfile   Log in to check your private messagesLog in to check your private messages   Log inLog in 


Assembly: puzzled about a jump instruction

 
Post new topic   Reply to topic    Cheat Engine Forum Index -> General programming
View previous topic :: View next topic  
Author Message
Csimbi
I post too much
Reputation: 97

Joined: 14 Jul 2007
Posts: 3330
PostPosted: Sun Sep 22, 2013 3:03 pm    Post subject: Assembly: puzzled about a jump instruction Reply with quote
Hi all,
I have encountered an instruction which leaves me puzzled because it does not seem to be doing what I am expecting it to be doing.

I attached two screenshots.
You'll see the following instruction on the first screenshot:
Code:
jmp dword ptr [eax*4+UFO.exe+34A7D0]


By all rights, when EAX==0, it should jump to UFO.exe+0x34A7D0 (=0x74A7D0). However, it simply jumps to the next instruction, as seen on the second screenshot (which shows the trace).

Could someone explain to me why does this happen?

Thanks!

CE_Jump_disasm.png
 Description:
 Filesize:  7.21 KB
 Viewed:  3705 Time(s)

CE_Jump_disasm.png
CE_Jump_trace.png
 Description:
 Filesize:  8.33 KB
 Viewed:  3705 Time(s)

CE_Jump_trace.png
Back to top
View user's profile Send private message
Dark Byte
Site Admin
Reputation: 471

Joined: 09 May 2003
Posts: 25824
Location: The netherlands
PostPosted: Sun Sep 22, 2013 3:25 pm    Post subject: Reply with quote
It will jump to the location the 4 byte value at ufo.exe+34a7d0 represents
In this case, that address contains the value ufo.exe+34a684
_________________
Do not ask me about online cheats. I don't know any and wont help finding them.

Like my help? Join me on Patreon so i can keep helping
Back to top
View user's profile Send private message MSN Messenger
Csimbi
I post too much
Reputation: 97

Joined: 14 Jul 2007
Posts: 3330
PostPosted: Sun Sep 22, 2013 8:13 pm    Post subject: Reply with quote
Meh, too easy Wink
Thanks!
Back to top
View user's profile Send private message
Display posts from previous:   
Post new topic   Reply to topic    Cheat Engine Forum Index -> General programming All times are GMT - 6 Hours
Page 1 of 1

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You cannot attach files in this forum
You can download files in this forum


Powered by phpBB © 2001, 2005 phpBB Group

CE Wiki   IRC (#CEF)   Twitter
Third party websites