Path: utzoo!attcan!uunet!wuarchive!mailrus!hellgate.utah.edu!uplherc!wicat!sarek!gsarff
From: gsarff@sarek.UUCP (Gary Sarff)
Newsgroups: comp.lang.c
Subject: Re: C Compiler for Unix V.2 Motorola 68020 Port
Message-ID: <00392@sarek.UUCP>
Date: 17 Feb 90 16:19:19 GMT
References: <1990Feb10.035315.1140@esegue.segue.boston.ma.us>
Organization: Programmers in Exile
Lines: 34

In article <1990Feb10.035315.1140@esegue.segue.boston.ma.us>, ray@ntmtka.mn.org (ray) writes:
>I am having a problem compiling the following source:
>
>main()
>{
>	long	x;
>	double	y;
>
>	x = -((long) y);
>}
>
>The faulty generated assembler code is :
> 
>	fneg.d((S%1-12).w,%fp),%d0
>
>The %d0 is obviously wrong.  This should be a floating poing register.
>
>
>Does anybody have any ideas where to start looking in the compiler code?
>Please use email.
>
>Thanks in advance.

I compiled this on my 68020 machine with no-optimization to see what it
was "thinking" and got the following assembler code
  	;trunc2	d:-12(a6),l:d0
	fintrz.d	-12(a6),fp2
	fmove.l	fp2,d0
	neg.l	d0
	move.l	d0,-4(a6)

I don't understand your question, the %d0 is not obviously wrong, "x" is
_not_ a floating point variable so why should the destination be a floating
point register?  Am I misunderstanding you here or what?