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From: Dan Cross <cross@math.psu.edu>
To: 9fans@cse.psu.edu
Subject: Re: [9fans] calling function with (variable number of) parameters
Date: Thu, 21 Jun 2001 10:13:57 -0400	[thread overview]
Message-ID: <200106211413.KAA16146@augusta.math.psu.edu> (raw)
In-Reply-To: <20010620155421.A1669@gmx.net>

In article <20010620155421.A1669@gmx.net> you write:
>I've already tried to write it in assembler. The problem is that after the
>function returns, I don't know how many args I have to pop from the stack.
>And I can't get the number from a local variable, because I don't know the
>frame pointer anymore (I modified SP pushing the args before I called the
>function).

So save space for n + 1 parameters on the stack; the last won't be used
by your called function, and you could store the number of parameters in
it.  When you return, pop the last item off the stack, and use that to
recalculate the frame pointer.

	- Dan C.



  parent reply	other threads:[~2001-06-21 14:13 UTC|newest]

Thread overview: 12+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2001-06-20 19:51 rog
2001-06-20 19:54 ` Latchesar Ionkov
2001-06-21 12:39   ` Douglas A. Gwyn
2001-06-21 13:48     ` Latchesar Ionkov
2001-06-21 14:13   ` Dan Cross [this message]
  -- strict thread matches above, loose matches on Subject: below --
2001-06-21 14:33 rog
2001-06-21 15:16 ` Dan Cross
2001-06-21 15:17 ` Latchesar Ionkov
2001-06-29 22:11   ` Boyd Roberts
2001-06-20 14:11 Latchesar Ionkov
2001-06-20 16:30 ` Douglas A. Gwyn
2001-06-20 18:23   ` Latchesar Ionkov

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