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Date: Mon, 7 Jun 2021 16:29:37 -0500
From: Segher Boessenkool <segher@kernel.crashing.org>
To: will schmidt <will_schmidt@vnet.ibm.com>
Cc: Michael Meissner <meissner@linux.ibm.com>, gcc-patches@gcc.gnu.org,
 David Edelsohn <dje.gcc@gmail.com>, Bill Schmidt <wschmidt@linux.ibm.com>,
 Peter Bergner <bergner@linux.ibm.com>
Subject: Re: [PATCH 2/2] Add IEEE 128-bit fp conditional move on PowerPC.
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On Thu, May 20, 2021 at 02:27:06PM -0500, will schmidt wrote:
> On Tue, 2021-05-18 at 16:28 -0400, Michael Meissner wrote:
> > +  if (compare_mode == result_mode
> > +      || (compare_mode == SFmode && result_mode == DFmode)
> > +      || (compare_mode == DFmode && result_mode == SFmode))
> > +    ;
> > +  else
> > +    return false;
> 
> Interesting if/else block.  May want to reverse the logic. I defer if
> this way is notably simpler than inverting it.

This is not simpler, no.  You want to do something that just returns
*first*, and then not have an "else".  *That* is simpler.

And just write !(...) around the condition, don't try to manually invert
it please.  You want both correct code and readable code, not neither of
these, they are not extremes you need to balance, each helps the other!


Segher