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Date: Mon, 23 Apr 2012 14:43:00 -0000
From: Alan Modra <amodra@gmail.com>
To: Steven Bosscher <stevenb.gcc@gmail.com>
Cc: Richard Guenther <richard.guenther@gmail.com>,	GCC Mailing List <gcc@gcc.gnu.org>,	Richard Guenther <rguenther@suse.de>
Subject: Re: A case where PHI-OPT pessimizes the code
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Mail-Followup-To: Steven Bosscher <stevenb.gcc@gmail.com>,	Richard Guenther <richard.guenther@gmail.com>,	GCC Mailing List <gcc@gcc.gnu.org>,	Richard Guenther <rguenther@suse.de>
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On Mon, Apr 23, 2012 at 02:50:13PM +0200, Steven Bosscher wrote:
>   csui = (ONEUL << a);
>   b = ((csui & cst) != 0);
>   if (b)
>     return 1;
>   else
>     return 0;

We (powerpc) would be much better if this were

   csui = (ONEUL << a);
   return (csui & cst) >> a;

Other targets would probably benefit too.

-- 
Alan Modra
Australia Development Lab, IBM