eqtype bug?

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Borsuc

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

Borsuc 13 Jan 2006, 18:25

just wanted to mention maybe it's not a bug, but I use:

Code:

if ~ p1 eqtype 0
  err
end if

p1 is a macro parameter. It works okay if I call it with 'eax'.. it gives error, which is good.. but it doesn't give error when I use a name, like 'Something'.. it's like it is a number?? Obviously it's a name.. another funny thing is:

Code:

if xxxx eqtype 0
  display 'xxxx'
end if

xxxx is, of course, not defined anywhere, so it's not a numeric constant.. Why does it display 'xxxx'? It this a bug?

PS: How can I be assured and preserve the FASM directives, numbers, etc.. like:

Code:

macro xxx p1, p2
{
  if ~ p1 eqtype 0
    err
  end if
  ; do somethin'
}


; some code
define 0 somethin'

; or
define eqtype ...

xxx 5, 10  ; this will not be generated properly, because
           ; '0' and 'eqtype' are replaced, even though
           ; in my code it isn't even obvious I use them

Is there a way I can be assured that some Fasm directives or numbers are preserved and local to a macro?

PS2: is err a good choice for stopping compilation errors? because it will give a 'invalid instruction' error, even though I use it for various purposes. Is

Code:

err "Parameter must be a numeric constant"

valid? Or what directive can I use to accomplish same thing? thank you

Regards Very Happy

13 Jan 2006, 18:25

Tomasz Grysztar

Joined: 16 Jun 2003
Posts: 8351
Location: Kraków, Poland

Tomasz Grysztar 13 Jan 2006, 18:55

Each unknown name for assembler is a label, it doesn't matter whether it actually gets defined or not - you can put a label inside the "if 0" block so it never gets defined actually, but it doesn't change a fact that for assembler it is a label - thus part of numerical expression.

So "xxx" is of the same type as "+xxx" and "xxx+0" - they are all numerical expressions (and "+xxx" is in fact equivalent to "xxx" for the assembler, so "xxx eq +xxx" is true condition).

Last edited by Tomasz Grysztar on 13 Jan 2006, 19:03; edited 2 times in total

13 Jan 2006, 18:55

Tomasz Grysztar

Joined: 16 Jun 2003
Posts: 8351
Location: Kraków, Poland

Tomasz Grysztar 13 Jan 2006, 18:59

As for the second problem you can do it like:

Code:

macro xxx p1, p2
{
  define eqtype eqtype
  define 0 0
  if ~ p1 eqtype 0
    err
  end if
  restore eqtype,0
}


define 0 somethin'

define eqtype ...

xxx 5, 10

13 Jan 2006, 18:59

Tomasz Grysztar

Joined: 16 Jun 2003
Posts: 8351
Location: Kraków, Poland

Tomasz Grysztar 13 Jan 2006, 19:05

And for the third one: the "err" is something like "ud2" opcode - you can be sure it will always cause an error and is fully backward-compatible, since there always wasn't any instruction of such name (except, of course, when you define such macro etc.)

13 Jan 2006, 19:05

Borsuc

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

Borsuc 13 Jan 2006, 19:07

Tomasz Grysztar wrote:

Each unknown name for assembler is a label, it doesn't matter whether it actually gets defined or not - you can put a label inside the "if 0" block so it never gets defined actually, but it doesn't change a fact that for assembler it is a label - thus part of numerical expression.

So "xxx" is of the same type as "+xxx" and "xxx+0" - they are all numerical expressions (and "+xxx" is in fact equivalent to "xxx" for the assembler, so "xxx eq +xxx" is true condition).

how to check if it is a number or is it impossible?
thanks for other replies. Very Happy

13 Jan 2006, 19:07

Tomasz Grysztar

Joined: 16 Jun 2003
Posts: 8351
Location: Kraków, Poland

Tomasz Grysztar 13 Jan 2006, 19:16

"eqtype" doesn't distinguish numerical expression, so any solution would be a tricky one.

13 Jan 2006, 19:16

Borsuc

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

Borsuc 13 Jan 2006, 19:25

just kidding Very Happy

i'm not sad Smile

thx

EDIT: what's ud2? It compiled ok.. I thought it was just an arbitrary name?

13 Jan 2006, 19:25

Tomasz Grysztar

Joined: 16 Jun 2003
Posts: 8351
Location: Kraków, Poland

Tomasz Grysztar 13 Jan 2006, 20:10

For UD2 see the Intel manuals. Wink

13 Jan 2006, 20:10

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