return value for macro

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khanh1984

Joined: 13 Jul 2009
Posts: 17

khanh1984 17 Jul 2009, 02:31

anyone thinks we should implement the macro in a way that allows ruturn value like a fuction.

A very simple example is an implementation of macro sizeof.

For every structure that are not yet defined sizeof structure inside I want to implement something looks like:

Code:

macro sizeof structure
{
virtual at 0
xyz structure
@:
abc = @-0 ;sizeof value here
return sizeof  ; now sizeof structure = size of that structure if structure is valid
}

of course there will be another way around but my example is the simplest solution and you can find many cases where you can use this feature.

17 Jul 2009, 02:31

khanh1984

Joined: 13 Jul 2009
Posts: 17

khanh1984 17 Jul 2009, 08:22

Dear Tomasz,

I've think of very simple idea to implement this feature. in macro we will add another type such as:

word macro sizeof Structure
{
macro inside here
return value
}
So when fasm encounters the macro above, it realizes that this macro is different from normal macro 'cause it has type 'word' in front. Then it decides to implement a normal macro of random name with same code inside, it will calculate all the value based on that macro. Finally, after have return value, it simplies define a constant with the name sizeof structure to that value.

What do you think about my idea. Please post your opinion.

17 Jul 2009, 08:22

Fanael

Joined: 03 Jul 2009
Posts: 168

Fanael 17 Jul 2009, 08:33

Tomasz, please don't implement inline macros in FASM!

17 Jul 2009, 08:33

khanh1984

Joined: 13 Jul 2009
Posts: 17

khanh1984 17 Jul 2009, 09:39

Fanael,
What do mean by inline macro ???
I only know inline asm in high-level language
and why do you think it is bad??? please give your answer in more detail?

17 Jul 2009, 09:39

Fanael

Joined: 03 Jul 2009
Posts: 168

Fanael 17 Jul 2009, 12:35

Tomasz Grysztar wrote:

No, inlining the macros is something against the fasm's concept. The macro in fasm is just a special kind of "mnemonic", which gets converted into chain of other lines by preprocessor. Just like each assembly language instruction spans one line, the macroinstruction spans one line.

http://board.flatassembler.net/topic.php?p=30436#30436

17 Jul 2009, 12:35

bitRAKE

Joined: 21 Jul 2003
Posts: 4016
Location: vpcmpistri

bitRAKE 17 Jul 2009, 13:43

Here are a couple way to implement return values:

Code:

macro sizeof structure {
        local ..xyz
 virtual at 0
                ..xyz structure
             sizeof.return = $ - ..xyz
   end virtual
}

macro sizeof return,structure {
   local ..xyz
 virtual at 0
                ..xyz structure
             return = $ - ..xyz
  end virtual
}

edit: thanks, LocoDelAssembly

Last edited by bitRAKE on 18 Jul 2009, 23:47; edited 2 times in total

17 Jul 2009, 13:43

Azu

Joined: 16 Dec 2008
Posts: 1159

Azu 18 Jul 2009, 03:49

Here you go

macro return value{
mov eax,value
ret
}

Last edited by Azu on 18 Jul 2009, 18:15; edited 1 time in total

18 Jul 2009, 03:49

Borsuc

Joined: 29 Dec 2005
Posts: 2465
Location: Bucharest, Romania

Borsuc 18 Jul 2009, 18:01

@Azu: shouldn't you reverse the name & parameter? Razz

18 Jul 2009, 18:01

LocoDelAssembly
Your code has a bug

Joined: 06 May 2005
Posts: 4624
Location: Argentina

LocoDelAssembly 18 Jul 2009, 18:27

bitRAKE's code needs a little adjustment, it is better to use "local ..xyz" to not interfere with the caller scope.

18 Jul 2009, 18:27

khanh1984

Joined: 13 Jul 2009
Posts: 17

khanh1984 23 Jul 2009, 06:44

bitRake:

I understand your macro but for the command like this:

mov eax, sizeof structure

how your macro fits in this situation. I mean when fasm encounters the line above, it will replace sizeof structure with your macro but the above like is one line command, your macro is 2 line so how you will be sure that Fasm will replace only sizeof.return value in that "mov" instruction.

23 Jul 2009, 06:44

bitRAKE

Joined: 21 Jul 2003
Posts: 4016
Location: vpcmpistri

bitRAKE 23 Jul 2009, 13:56

FASM doesn't support inline macros, and I'm not attempting to solve inline (one line) macro problem. Use two lines in source code. Example, http://board.flatassembler.net/topic.php?t=10472

23 Jul 2009, 13:56

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