mov eax,neg 1000h

Index > Main > mov eax,neg 1000h

Author

Thread

ouadji

Joined: 24 Dec 2008
Posts: 1081
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

_________________
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: 19872
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: 3892
Location: vpcmipstrm

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: 1081
Location: Belgium

ouadji 03 Nov 2010, 16:06

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

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

_________________
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: 19872
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: 1081
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

_________________
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: 19872
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: 3892
Location: vpcmipstrm

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

_________________
¯\(°_o)/¯ “languages are not safe - uses can be” Bjarne Stroustrup

04 Nov 2010, 00:52

< 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