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comrade

Joined: 16 Jun 2003
Posts: 1138
Location: Russian Federation

comrade

Is it possible to do something like $B that points to previous instruction?

Code:

nop
; at this point, $B points to nop
xor eax,eax
; at this point, $B points to xor eax,eax
inc eax
; at this point, $B points to inc eax

For example, to find size of instruction I do:

Code:

.x = $
movzx   eax,al
display $-.x+30h

But with $B would be much simpler, and I could have a macro to do it:

Code:

macro showsize {
display ($-$B)+30h
}

_________________
comrade (comrade64@live.com; http://comrade.ownz.com/)

29 May 2004, 17:27

Tommy

Joined: 17 Jun 2003
Posts: 489
Location: Norway

Tommy

Seems to be a good idea if it's possible... Wink

29 May 2004, 18:54

comrade

Joined: 16 Jun 2003
Posts: 1138
Location: Russian Federation

comrade

Maybe there could other uses for it, but I cannot think of any.

_________________
comrade (comrade64@live.com; http://comrade.ownz.com/)

29 May 2004, 19:05

Tommy

Joined: 17 Jun 2003
Posts: 489
Location: Norway

Tommy

A solution:

Code:

macro showsize asm_code {
  local x
  x = $
  asm_code
  display $ - x + 30h, 13, 10
}

use32
showsize <movzx eax, al>

29 May 2004, 19:37

comrade

Joined: 16 Jun 2003
Posts: 1138
Location: Russian Federation

comrade

That works, but not as elegant as it would be with $B. Encapsulating instruction into showsize <> is extra work I was hoping to avoid.

_________________
comrade (comrade64@live.com; http://comrade.ownz.com/)

29 May 2004, 21:37

Tomasz Grysztar

Joined: 16 Jun 2003
Posts: 7991
Location: Kraków, Poland

Tomasz Grysztar

Well, to avoid <> characters you can do it this way:

Code:

macro showsize [asm_code] {
  common local x
  x = $
  asm_code
  display $ - x + 30h, 13, 10
}

showsize movzx eax, al

And I'm sorry, there seems to be no simple way to add such feature as $B you suggested.

30 May 2004, 01:30

comrade

Joined: 16 Jun 2003
Posts: 1138
Location: Russian Federation

comrade

that's good enough, thanks Smile

_________________
comrade (comrade64@live.com; http://comrade.ownz.com/)

30 May 2004, 03:51

Tommy

Joined: 17 Jun 2003
Posts: 489
Location: Norway

Tommy

There I learned something new about FASM macro-technology... Thanks, Privalov!

30 May 2004, 09:59

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