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Date: Sun, 23 May 2021 21:26:00 -0400
From: Mike Frysinger <vapier@gentoo.org>
To: Faraz Shahbazker <fshahbazker@wavecomp.com>
Cc: gdb-patches@sourceware.org, "Maciej W . Rozycki" <macro@orcam.me.uk>,
 Chao-ying Fu <cfu@wavecomp.com>
Subject: Re: [EXTERNAL]Re: [PATCH 2/5] sim: Factor out NaN handling in
 floating point operations
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 gdb-patches@sourceware.org,
 "Maciej W . Rozycki" <macro@orcam.me.uk>,
 Chao-ying Fu <cfu@wavecomp.com>
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On 23 May 2021 12:02, Faraz Shahbazker wrote:
> On 5/22/21 6:55 AM, Mike Frysinger wrote:
> > so some of the logic you replaced below do:
> > 	if (sim_fpu_is_qnan (l))
> > 	  {
> > 	    *f = *l;
> > 	    return 0;
> > 	  }
> > 	if (sim_fpu_is_qnan (r))
> > 	  {
> > 	    *f = *r;
> > 	    return 0;
> > 	  }
> > 
> > but others do:
> > 	if (sim_fpu_is_qnan (l))
> > 	  {
> > 	    *f = *l;
> > 	    f->class = sim_fpu_class_qnan;
> > 	    return 0;
> > 	  }
> > 	if (sim_fpu_is_qnan (r))
> > 	  {
> > 	    *f = *r;
> > 	    f->class = sim_fpu_class_qnan;
> > 	    return 0;
> > 	  }
> > 
> > it seems like we should have been consistently doing the latter ?
> 
> Isn't the extra assignment redundant? If sim_fpu_is_qnan(l), then 
> l->class == sim_fpu_class_qnan, and so *f = *l is sufficient.
> 
> Only sNaN-handling needs the extra assignment because it has to be 
> downgraded to qNaN.

gotcha, sounds good.  so the old code that was assigning the class didn't
need to, and you're cleaning that up.
-mike