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Date: Mon, 14 Sep 2015 20:38:00 -0000
From: Joseph Myers <joseph@codesourcery.com>
To: Richard Biener <richard.guenther@gmail.com>
CC: David Sherwood <david.sherwood@arm.com>, GCC Patches	<gcc-patches@gcc.gnu.org>, Richard Sandiford <Richard.Sandiford@arm.com>
Subject: Re: [PING][Patch] Add support for IEEE-conformant versions of scalar fmin* and fmax*
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On Mon, 14 Sep 2015, Richard Biener wrote:

> To make progess here I think adding new optabs is fine.  So can you
> split out that part and implement builtin expanders
> for fmin/max instead?
> 
> Btw, FMIN/MAX_EXPR are not commutative AFAIK because of behavior for
> fmax (-NaN, NaN)
> vs. fmax (NaN, -NaN)?

For those cases, it's unspecified which NaN is returned, so they can be 
considered commutative (and likewise for the case when the arguments are 0 
and -0).

-- 
Joseph S. Myers
joseph@codesourcery.com