mov eax,neg 1000h

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ouadji

Joined: 24 Dec 2008
Posts: 1080
Location: Belgium

ouadji 03 Nov 2010, 14:54

Code:

mov eax, neg 1000h

yes ... i could easily do it with "0-1000h"
but it would be more elegant, more "neat", with "neg". Wink

(never satisfied (me) ... yes, it is also true ! Razz

)

a little macro bitRAKE ? <-- Wink

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I am not young enough to know everything (Oscar Wilde)-

03 Nov 2010, 14:54

JohnFound

Joined: 16 Jun 2003
Posts: 3499
Location: Bulgaria

JohnFound 03 Nov 2010, 14:59

ouadji wrote:

Code:
mov eax, neg 1000h
    
yes ... i could easily do it with "0-1000h"
but it would be more elegant, more "neat", with "neg".

(never satisfied (me) ... yes, it is also true ! )

a little macro bitRAKE ? <--

Why not simply:

Code:

mov eax, -1000h

Or better:

Code:

mov eax, -$1000

03 Nov 2010, 14:59

revolution
When all else fails, read the source

Joined: 24 Aug 2004
Posts: 20657
Location: In your JS exploiting you and your system

revolution 03 Nov 2010, 15:02

Or even better Wink

Code:

mov eax,-0x1000

03 Nov 2010, 15:02

bitRAKE

Joined: 21 Jul 2003
Posts: 4249
Location: vpcmpistri

bitRAKE 03 Nov 2010, 15:09

Code:

macro mov dest,src {
  temp equ src
  match =neg num,src \{
    restore temp
    temp equ -num
  \}
  mov dest,num
}

...just off the top of my head. Wink

03 Nov 2010, 15:09

baldr

Joined: 19 Mar 2008
Posts: 1651

baldr 03 Nov 2010, 15:47

ouadji,

I've seen a = -1*b at least once.

----8<----
bitRAKE,

imul dest, src, -1 probably will handle all other flavors of src, then. Wink

03 Nov 2010, 15:47

ouadji

Joined: 24 Dec 2008
Posts: 1080
Location: Belgium

ouadji 03 Nov 2010, 16:06

ok ... i still missed a good opportunity to keep quiet ! Wink

imul dest, src, -1 <--- Laughing

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I am not young enough to know everything (Oscar Wilde)-

03 Nov 2010, 16:06

revolution
When all else fails, read the source

Joined: 24 Aug 2004
Posts: 20657
Location: In your JS exploiting you and your system

revolution 03 Nov 2010, 16:10

baldr wrote:

imul dest, src, -1 probably will handle all other flavors of src, then.

Should that be: imul dest, src, neg 1? Razz

03 Nov 2010, 16:10

ouadji

Joined: 24 Dec 2008
Posts: 1080
Location: Belgium

ouadji 03 Nov 2010, 16:15

Quote:

Should that be: imul dest, src, neg 1

revolution, you make me laugh

some recursion ? Very Happy

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I am not young enough to know everything (Oscar Wilde)-

03 Nov 2010, 16:15

baldr

Joined: 19 Mar 2008
Posts: 1651

baldr 03 Nov 2010, 17:33

revolution,

Isn't it my turn to be Mr. Hyde? Wink

03 Nov 2010, 17:33

revolution
When all else fails, read the source

Joined: 24 Aug 2004
Posts: 20657
Location: In your JS exploiting you and your system

revolution 04 Nov 2010, 00:09

ouadji: You can also use this:

Code:

neg fix -

baldr wrote:

Isn't it my turn to be Mr. Hyde?

Okay, tag, you're it. I'll try to be the smart Dr. J but I'm not sure I can do it as well as you.

04 Nov 2010, 00:09

bitRAKE

Joined: 21 Jul 2003
Posts: 4249
Location: vpcmpistri

bitRAKE 04 Nov 2010, 00:52

Code:

macro mov dest,src {
  temp equ src
  match =neg num,src \{
    restore temp
    temp equ -num
  \}
  mov dest,temp
  restore temp
}

...fixed.

He aska for a macro I give 'em a macro.

The pattern works for all kinds of domain specific syntax tweaks.

"NEG fix -" woo, scary.

Actually, it would be trivial to add NEG to FASM's expression calculator.

Code:

single_operand_operators:
 db 1,'+',0
 db 1,'-',083h
 db 3,'neg',083h
 db 3,'not',0D0h
 db 3,'plt',0E1h
 db 3,'rva',0E0h
 db 0

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04 Nov 2010, 00:52

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