Whitespace and its use in macroinstructions

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hafai

Joined: 12 Jun 2011
Posts: 8

hafai 08 Dec 2011, 00:13

I'm looking to use whitespace in my macroinstructions, more specifically a tab character in its name. But as macronames aren't quote-enclosed something like the following won't work.

Code:

macro "\t rest_of_macro_name" arg

I'm not even sure if fasm understands escape-sequences like that as I have always had to manually enter the hex-value of what normally would be escaped when writing string literals. So basically I'm looking for confirmation as to whether or not I need to find a new way to achieve what I want.[/code]

08 Dec 2011, 00:13

AsmGuru62

Joined: 28 Jan 2004
Posts: 1657
Location: Toronto, Canada

AsmGuru62 08 Dec 2011, 01:05

Curious.... why that feature may be needed?
What does a TAB in the macro name can be used for?

08 Dec 2011, 01:05

hafai

Joined: 12 Jun 2011
Posts: 8

hafai 08 Dec 2011, 04:45

I actually want to create a macro that has the name of something like a tab or a certain number of spaces. It would then have the next word tell it which sub part (with an if statement) of the macro to execute. So something like, "[TAB]/[certain number of spaces] sub-part args" would call the [TAB] macro with the name and args. As I already format my code using tabs I could then naturally invoke my macros without having to remember the [TAB]. And as long as I don't create a sub-part that has the name of a standard assembly instruction then the if statements would cause normal instructions to operate normally.

I'm not sure if I'm describing what I want to do quite right but I just need to know if FASM can do this by default. If not then I guess I'll have to re-compile it with some modifications to handle what I want.

08 Dec 2011, 04:45

addes3

Joined: 09 May 2011
Posts: 29

addes3 08 Dec 2011, 20:56

Sorry, but this is not supported by FASM, as it removes all extra whitespace. FASM doesn't support escape-sequences.

This is an extremely odd request. Just so you know, a macro can use old macros with the same name or the actual instruction.

Example:

Code:

macro mov op1,op2,op3
{
   if op3 eq
      mov op1,2op2
   else
      mov op1,op2
      mov op2,op3
   end if
}

08 Dec 2011, 20:56

hafai

Joined: 12 Jun 2011
Posts: 8

hafai 09 Dec 2011, 12:50

I was aware of 'overloading' an instruction with macro-instructions as the preprocessor just outputs assembly (well, text that the rest of the assembler hopes is legal source code for the following stages). I may have found a better solution for my problem. One that may actually be far better.

But I have one more question. Does the preprocessor get run on the source code several times? Until it returns with no changes? So if in the process of resolving a macro-instruction it creates a new one it would then resolve the new one during a second run through?

09 Dec 2011, 12:50

revolution
When all else fails, read the source

Joined: 24 Aug 2004
Posts: 20416
Location: In your JS exploiting you and your system

revolution 09 Dec 2011, 20:34

hafai wrote:

But I have one more question. Does the preprocessor get run on the source code several times?

The preprocessor is single-pass. The assembler is multi-pass.

09 Dec 2011, 20:34

hafai

Joined: 12 Jun 2011
Posts: 8

hafai 09 Dec 2011, 21:30

Okay. Thank you.

09 Dec 2011, 21:30

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