JUMP instruction bug I've seen for me

flat assembler
Message board for the users of flat assembler.

Index > Main > JUMP instruction bug I've seen for me

Author

Thread

Diicorp95

Joined: 18 Mar 2021
Posts: 3

Diicorp95 18 Mar 2021, 13:17

Hello, people! Do you have any idea why

Code:

jmp 0x00007E00

compiles into

Code:

jmp 0x00000200

?

I'm sure that I did everything OK. Sad

18 Mar 2021, 13:17

Diicorp95

Joined: 18 Mar 2021
Posts: 3

Diicorp95 18 Mar 2021, 13:53

I think that's because of org 0x7C00, because 0x7E00 - 0x7C00 = 0x0200...

18 Mar 2021, 13:53

revolution
When all else fails, read the source

Joined: 24 Aug 2004
Posts: 20571
Location: In your JS exploiting you and your system

revolution 18 Mar 2021, 16:20

All jmp and call instructions are IP relative when you use an immediate operand.

Everything is as expected.

18 Mar 2021, 16:20

Diicorp95

Joined: 18 Mar 2021
Posts: 3

Diicorp95 19 Mar 2021, 15:15

revolution wrote:

All jmp and call instructions are IP relative when you use an immediate operand.

Everything is as expected.

I've tested it on zero-filled IP.

19 Mar 2021, 15:15

< Last Thread | Next Thread >

Forum Rules:

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