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<div class="moz-cite-prefix">On 2/28/2018 5:46 PM, Chris Lattner
wrote:<br>
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cite="mid:900CDC6D-15A2-488C-B19D-EBCB8A73775D@nondot.org">
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On Feb 28, 2018, at 3:29 PM, Kaylor, Andrew via llvm-dev <<a
href="mailto:llvm-dev@lists.llvm.org" class=""
moz-do-not-send="true">llvm-dev@lists.llvm.org</a>> wrote:<br
class="">
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class="">For the first part of Sanjay’s question, I
think the answer is, “Yes, we can fold all of these to
NaN in the general case.” </span></div>
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<div>Agreed. Those IR instructions are undefined on SNAN, and
that undef could take on an SNAN value. Folding these
instructions to undef seems reasonable, and it is arguable
that you could even fold it to an ‘unreachable'.</div>
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fdiv snan, snan is undefined? As opposed to producing a qnan, as
specified by IEEE-754?<br>
<p>-Eli<br>
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<pre class="moz-signature" cols="72">--
Employee of Qualcomm Innovation Center, Inc.
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project</pre>
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