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Tomasz Grysztar



Joined: 16 Jun 2003
Posts: 7802
Location: Kraków, Poland
Tomasz Grysztar
Very simple to do, just open ASSEMBLE.INC file and find the "instruction_assembler" label (around the line 324), and then instruction
Code:
        jnz     extra_characters_on_line    

5 lines below that label.
By changing this instruction to:
Code:
        jnz     assemble_line    

you will get tweaked fasm version, which will accept such an awful multi-instruction lines like this:
Code:
mov eax,0 inc ebx mov eax,[ebx] org 700h mov eax,$    


Last edited by Tomasz Grysztar on 28 Jul 2004, 17:20; edited 1 time in total
Post 28 Jul 2004, 10:09
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crc



Joined: 21 Jun 2003
Posts: 637
Location: Penndel, PA [USA]
crc
Very cool -- now it's pretty close to the syntax I'm using in the assembler I'm writing for use with RetroForth Smile
Post 28 Jul 2004, 10:43
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fasm9



Joined: 19 Jun 2003
Posts: 439
fasm9
awesome!

--
PS: In VIM, you can change it like this.
debian:~/fasm/source# vi assemble.inc
:329s/extra_characters_on_line/assemble_line
:wq
debian:~/fasm/source# _
Post 28 Jul 2004, 10:59
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crc



Joined: 21 Jun 2003
Posts: 637
Location: Penndel, PA [USA]
crc
Any chance of being able to use macros with this? I use a bunch of macros that don't take arguments and would love to be able to string them together with assembly code Smile
Post 28 Jul 2004, 12:05
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Tomasz Grysztar



Joined: 16 Jun 2003
Posts: 7802
Location: Kraków, Poland
Tomasz Grysztar
I'm afraid preprocessor cannot be tweaked so simply.
Post 28 Jul 2004, 17:06
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Joshua



Joined: 12 Jul 2003
Posts: 56
Location: Belgium
Joshua
Well if you could get this to work on preprocessor too, it would solve our multiline fix problem!

Thanks, and keep at it...

PS i hope this tweak (and the preproccor part) can make it in the official version, although i still think a specific character for allowing this would be better
Post 28 Jul 2004, 17:31
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Tommy



Joined: 17 Jun 2003
Posts: 489
Location: Norway
Tommy
I agree Joshua...
Post 28 Jul 2004, 17:35
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Tomasz Grysztar



Joined: 16 Jun 2003
Posts: 7802
Location: Kraków, Poland
Tomasz Grysztar
I'm not going to include it in official releases, too confusing trick. That's why I only posted it here as a kind of curiosity.

But for your problem Joshua, here's another, a bit more complex modification, which I may include in next official version.

All modifications have to be made in PREPROCE.INC

1) find "preprocess_line" label (line 248), after:
Code:
        push    [struc_name]
        push    ecx esi    

put new label:
Code:
      preprocess_current_line:    


2) find "skip_macro_block" label (line 960), before the "skip_macro_symbol" you have the instructions:
Code:
        lods    byte [esi]
        or      al,al
        jnz     extra_characters_on_line
        and     [macro_status],0F0h
        jmp     line_preprocessed    

Change them to:
Code:
        and     [macro_status],0F0h
        lods    byte [esi]
        or      al,al
        jz      line_preprocessed
        dec     esi
        mov     ecx,edi
        sub     ecx,esi
        lea     esi,[esi+ecx-1]
        lea     edi,[edi+1+16]
        mov     ebx,edi
        dec     edi
        std
        rep     movs byte [edi],[esi]
        cld
        sub     edi,16-1
        mov     byte [edi-1],0
        mov     esi,[current_line]
        mov     [current_line],edi
        mov     ecx,4
        rep     movs dword [edi],[esi]
        mov     edi,ebx
        jmp     preprocess_current_line
      skip_macro_symbol:
        movzx   eax,byte [esi]
        inc     esi
        add     esi,eax
        jmp     skip_macro_block
      skip_macro_string:
        lods    dword [esi]
        add     esi,eax
        jmp     skip_macro_block    


This allows putting any instruction or directive in the line after the } symbol ending macro definition.
Example of possible usage:

Code:
macro struct name
 {
   common
   name@struct fix name
   struc name {
 }

macro struct_helper name
 {
   virtual at 0
   name name
   sizeof.#name = $ - name
   name equ sizeof.#name
   end virtual
 }

ends fix } struct_helper name@struct

; And now some nice definition:

struct RECT
   .left   dd ?
   .top    dd ?
   .right  dd ?
   .bottom dd ?
ends    
Post 28 Jul 2004, 18:19
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crc



Joined: 21 Jun 2003
Posts: 637
Location: Penndel, PA [USA]
crc
Quote:
I'm not going to include it in official releases, too confusing trick. That's why I only posted it here as a kind of curiosity.


I can understand that. Even so, I think I'll keep the hack in my copy of FASM Smile
Post 28 Jul 2004, 23:23
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Tomasz Grysztar



Joined: 16 Jun 2003
Posts: 7802
Location: Kraków, Poland
Tomasz Grysztar
Question to everyone: would you want/accept this second change (allowing instructions/directives after macro ending character) in official releases?
Post 29 Jul 2004, 09:53
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decard



Joined: 11 Sep 2003
Posts: 1092
Location: Poland
decard
Of course, as it would make FASM preprocessor more powerful Wink
Post 29 Jul 2004, 10:08
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Tommy



Joined: 17 Jun 2003
Posts: 489
Location: Norway
Tommy
Yes! That would be great, Privalov! Wink
Post 29 Jul 2004, 10:22
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crc



Joined: 21 Jun 2003
Posts: 637
Location: Penndel, PA [USA]
crc
Sure, keep the second change in the official releases. It doesn't hurt anything from what I've seen, and actually makes some things easier
Post 29 Jul 2004, 10:49
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Tomasz Grysztar



Joined: 16 Jun 2003
Posts: 7802
Location: Kraków, Poland
Tomasz Grysztar
OK, I will also replace the "struct" macro in the standard includes with this version - it makes the includes much more elegant.
Post 29 Jul 2004, 11:27
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Tomasz Grysztar



Joined: 16 Jun 2003
Posts: 7802
Location: Kraków, Poland
Tomasz Grysztar
One side-effect of this feature is that you can define multiple macros in the same line, like:
Code:
macro alpha {db 1} macro beta {db 2} macro gamma {db 3}    
Post 29 Jul 2004, 12:57
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pelaillo
Missing in inaction


Joined: 19 Jun 2003
Posts: 878
Location: Colombia
pelaillo
Very good!
Even the first tweak could be in the official release as long as it didn't become an habit to write such kind of code.
In other words, compiler has the power but programmers the good sense to write readable code, given that even without the tweax exist the possibility to write obfuscated code Smile
Post 29 Jul 2004, 13:03
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Imagist



Joined: 13 Jun 2004
Posts: 114
Location: Pennsylvania (USA)
Imagist
If bad programmers start abusing the powers you add to FASM, you can just remove the changes from the next version of FASM. Very Happy

Ugh, I can't imagine the horror of wading through a FASM program written on one line. I've done it with a C program that had been reverse compiled and posted on a site (the guy's program wasn't programmed to add white space) and that was miserable, but at least then I had semicolons to tell me where the statements ended.

I like FASM the way it is. There's no point adding stuff that no good programmer will ever use. But it's like I said, if it becomes a problem you can always take it out.
Post 29 Jul 2004, 14:49
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vid
Verbosity in development


Joined: 05 Sep 2003
Posts: 7105
Location: Slovakia
vid
i like second one (commands behind "}"), unless it little bit "unsyntactical" it solves few problems so it's OK.
First one, of course, no.
Post 29 Jul 2004, 18:23
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Tomasz Grysztar



Joined: 16 Jun 2003
Posts: 7802
Location: Kraków, Poland
Tomasz Grysztar
vid: so we agree.
Post 29 Jul 2004, 18:32
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Joshua



Joined: 12 Jul 2003
Posts: 56
Location: Belgium
Joshua
Thanks priv! This is all i needed...

Now for the next question: When will the new official fasm version (with this feature in it) be released? Wink
Post 29 Jul 2004, 18:35
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