local macro namespace and virtual names conflict

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strap89

Joined: 15 Feb 2009
Posts: 23
Location: Russia

strap89 28 Feb 2009, 16:42

Hi!
Please say, what wrong in this code:

Code:

struc ST {.x db ?}
d1 ST
d2 ST
macro MC NST
{
       local dv
    virtual at d#NST
            dv ST
       end virtual
 mov eax,dv.x
}
MC 1
MC 2

Fasm say: dv.x undefined
But when i remove 'local dv' and 'MC 2' fasm compile OK.

Code:

struc ST {.x db ?}
d1 ST
d2 ST
macro MC NST
{
   ;local dv
   virtual at d#NST
            dv ST
       end virtual
 mov eax,dv.x
}
MC 1
;MC 2

P.S. i'm need remove 'MC 2' because 'dv' already defined.

28 Feb 2009, 16:42

Tomasz Grysztar

Joined: 16 Jun 2003
Posts: 8359
Location: Kraków, Poland

Tomasz Grysztar 28 Feb 2009, 16:44

The "dv.x" is seen by fasm as one whole name, so the "dv" local is not recognized inside it. The correct way to do it is:

Code:

struc ST {.x db ?}
d1 ST 
d2 ST 
macro MC NST 
{ 
        local dv 
        virtual at d#NST 
                dv ST 
        end virtual 
        mov eax,dv#.x
} 
MC 1 
MC 2

28 Feb 2009, 16:44

strap89

Joined: 15 Feb 2009
Posts: 23
Location: Russia

strap89 28 Feb 2009, 17:11

Big thanks!
I have another small problem (similar), may it be writed in this thread?

Code:

macro DD NV {d#NV dd NV}
rept 4 counter
{
    DD counter-1
}

Goal is to have zero based names, but it not work.

28 Feb 2009, 17:11

LocoDelAssembly
Your code has a bug

Joined: 06 May 2005
Posts: 4624
Location: Argentina

LocoDelAssembly 28 Feb 2009, 17:16

TFM kindly says wrote:

The counter symbol by default counts from 1, but you can declare different
base value by placing the number preceded by colon immediately after the name
of counter. For example:

rept 8 n:0 { pxor xmm#n,xmm#n }

28 Feb 2009, 17:16

strap89

Joined: 15 Feb 2009
Posts: 23
Location: Russia

strap89 28 Feb 2009, 17:22

That is not complete solution:

Code:

macro DD NV {d#NV dd NV}
rept 4 counter
{
      DD counter*2
}

Problem returned. That is only example, i'm try understand what is it in place after #. From documentation:"It can be useful, because
it’s done after the arguments and local names are replaced with their values". So it must be a number... or not calculated expression?

28 Feb 2009, 17:22

revolution
When all else fails, read the source

Joined: 24 Aug 2004
Posts: 20459
Location: In your JS exploiting you and your system

revolution 28 Feb 2009, 17:27

Code:

irp counter,0,2,4,6 { ... }

28 Feb 2009, 17:27

revolution
When all else fails, read the source

Joined: 24 Aug 2004
Posts: 20459
Location: In your JS exploiting you and your system

revolution 28 Feb 2009, 17:29

See here also.

28 Feb 2009, 17:29

strap89

Joined: 15 Feb 2009
Posts: 23
Location: Russia

strap89 28 Feb 2009, 18:09

Great examples! I'm like such code. But problem not solved:

Code:

macro pre_dec result,x {
        match xx,x { 
                rept xx j:0 { 
                        result equ j 
                \\} 
        \} 
}
macro DD NV
{
display 'NV=',NV+30h,13,10
        d#NV dd NV
}
rept 4 counter
{
    pre_dec result,counter
      mov eax,result
      DD result
}

It work as EQU, mov eax ,result compiled OK. But after # it not compiled. May be after # we work with expression, not with it value (may be problem come only at one of pass).
By the way, in this code compiler error is: symbol already defined, but display show different numbers, but previous code say: illegal instruction.
May be it's posiible to know: what symbol already defined. Is it d0 or d1 or d3 or may be dresult? Please, i'm try to understand rules to use such code.

28 Feb 2009, 18:09

revolution
When all else fails, read the source

Joined: 24 Aug 2004
Posts: 20459
Location: In your JS exploiting you and your system

revolution 28 Feb 2009, 23:55

strap89 wrote:

compiler error is: symbol already defined

Use local to solve that problem:

Code:

local result

28 Feb 2009, 23:55

strap89

Joined: 15 Feb 2009
Posts: 23
Location: Russia

strap89 01 Mar 2009, 04:24

I'm try define GLOBAL symbols with different names - local not usable.

01 Mar 2009, 04:24

revolution
When all else fails, read the source

Joined: 24 Aug 2004
Posts: 20459
Location: In your JS exploiting you and your system

revolution 01 Mar 2009, 04:35

Use both local and then match to dereference "result" into the value EUQated. Or, if the list is lot too large, use irp as above.

01 Mar 2009, 04:35

strap89

Joined: 15 Feb 2009
Posts: 23
Location: Russia

strap89 01 Mar 2009, 05:04

In previous sample i'm ry to use EQU - it not work.
IMHO I'm understand problem: name after # resolved to there value, but resolution have only one level (nested expression no resolved).

Code:

macro A
{
  name#1 dd 0
 XF equ 1
    pame#XF dd 1
        YF fix 2
    rame#YF dd 1
        ZF fix YF
   wame#ZF dd 1
}
A

This code produce such names (generated by symbols.exe utility):
name1: defined in {line generated by a.asm[11] from a.asm[3]}
pameXF: defined in {line generated by a.asm[11] from a.asm[5]}
rame2: defined in {line generated by a.asm[11] from a.asm[7]}
wameXF: defined in {line generated by a.asm[11] from a.asm[9]}
1. digit converted to digit itself
2. equ not converted (it's name used). It's not shown but XF=1 work as equ.
3. fix converted to it's value
4. double fix (ZF) converted to name of previous level (YF).

01 Mar 2009, 05:04

revolution
When all else fails, read the source

Joined: 24 Aug 2004
Posts: 20459
Location: In your JS exploiting you and your system

revolution 01 Mar 2009, 05:13

strap89 wrote:

(nested expression no resolved)

Did you see my last post? match can do the conversion for the values.

01 Mar 2009, 05:13

strap89

Joined: 15 Feb 2009
Posts: 23
Location: Russia

strap89 01 Mar 2009, 05:33

I'm see last post but i'm not understand what you meen. How dereference LOCAL name into GLOBAL namespace? Simple EQU not work.

01 Mar 2009, 05:33

revolution
When all else fails, read the source

Joined: 24 Aug 2004
Posts: 20459
Location: In your JS exploiting you and your system

revolution 01 Mar 2009, 06:11

strap89 wrote:

I'm see last post but i'm not understand what you meen. How dereference LOCAL name into GLOBAL namespace? Simple EQU not work.

Code:

macro DD NV {d#NV dd NV}

macro pre_mul result,x,y {
        match xx yy,x y {
                result equ xx
                rept xx {
                        match w,result {
                                rept yy j:w {
                                        result equ j
                                \\\\}
                        \\\}
                \\}
        \}
} 

rept 400 counter:0 {
  local result
        pre_mul result,counter,2
    match r,result \{
             DD r
        \}
}

mov eax,d4
mov eax,d10
mov eax,d400

01 Mar 2009, 06:11

strap89

Joined: 15 Feb 2009
Posts: 23
Location: Russia

strap89 01 Mar 2009, 12:42

Thanks!
Now i'm begin to undestand how it work. But at least at this example local is not needed, compiled ok without it. 'pre_mul' preset 'result' and not use it previous value.

01 Mar 2009, 12:42

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