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Hello Gabriele,<br>
<br>
It is possible that the feature is not enabled on the Arm platform. I see some special handling for X86_64 for this feature.<br>
<br>
<a href="https://github.com/flang-compiler/flang/blob/cb42a171b6462b2f3acd3e1841a56a1ae08291ef/tools/flang2/flang2exe/llassem.cpp#L1129">https://github.com/flang-compiler/flang/blob/cb42a171b6462b2f3acd3e1841a56a1ae08291ef/tools/flang2/flang2exe/llassem.cpp#L1129</a><br>
<br>
--Kiran</div>
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<div id="divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" style="font-size:11pt" color="#000000"><b>From:</b> Jost, Gabriele (ARC-TNC)[Supersmith] <gabriele.jost@nasa.gov><br>
<b>Sent:</b> 23 April 2020 19:49<br>
<b>To:</b> Kiran Chandramohan <Kiran.Chandramohan@arm.com><br>
<b>Cc:</b> flang-dev@lists.llvm.org <flang-dev@lists.llvm.org><br>
<b>Subject:</b> Re: [EXTERNAL] Re: arm + denormals</font>
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<p class="x_MsoNormal">Many thanks. I will give this a try. Yes, indeed, it is for the arm platform.</p>
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<p class="x_MsoNormal"><span style="font-size:10.5pt; color:black">Gabriele Jost</span></p>
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<p class="x_MsoNormal"><b><span style="font-size:12.0pt; color:black">From: </span>
</b><span style="font-size:12.0pt; color:black">Kiran Chandramohan <Kiran.Chandramohan@arm.com><br>
<b>Date: </b>Thursday, April 23, 2020 at 11:37 AM<br>
<b>To: </b>"Jost, Gabriele (ARC-TNC)[Supersmith]" <gabriele.jost@nasa.gov><br>
<b>Cc: </b>"flang-dev@lists.llvm.org" <flang-dev@lists.llvm.org><br>
<b>Subject: </b>Re: [EXTERNAL] Re: arm + denormals</span></p>
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<p class="x_MsoNormal"><span style="font-size:12.0pt; color:black">Ahh.<br>
<br>
What about Mflushz? <br>
Also, Is this question specifically for the Arm platform?<br>
<br>
--Kiran</span></p>
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<p class="x_MsoNormal"><b><span style="color:black">From:</span></b><span style="color:black"> Jost, Gabriele (ARC-TNC)[Supersmith] <gabriele.jost@nasa.gov><br>
<b>Sent:</b> 23 April 2020 19:14<br>
<b>To:</b> Kiran Chandramohan <Kiran.Chandramohan@arm.com><br>
<b>Subject:</b> Re: [EXTERNAL] Re: arm + denormals</span> </p>
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<p class="x_xmsonormal">Thanks for the reply, Kiran. So, the message comes from the code itself, not from the compiler. There are denormals, but if the compiler could flush those to 0, the code would not detect them, I think. The denormals don’t impact the
results, just the timings, because the code checks for them.</p>
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<p class="x_xmsonormal"><span style="font-size:10.5pt; color:black">Scientific & HPC Application P.O. Box 1</span></p>
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<p class="x_xmsonormal"><b><span style="font-size:12.0pt; color:black">From: </span>
</b><span style="font-size:12.0pt; color:black">Kiran Chandramohan <Kiran.Chandramohan@arm.com><br>
<b>Date: </b>Thursday, April 23, 2020 at 11:07 AM<br>
<b>To: </b>"flang-dev@lists.llvm.org" <flang-dev@lists.llvm.org>, "Jost, Gabriele (ARC-TNC)[Supersmith]" <gabriele.jost@nasa.gov><br>
<b>Subject: </b>[EXTERNAL] Re: arm + denormals</span></p>
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<p class="x_xmsonormal"><span style="font-size:12.0pt; color:black">Hello Gabriele,<br>
<br>
Does setting the environment variable NO_STOP_MESSAGE help?</span><br>
<span style="font-size:12.0pt; color:black">export NO_STOP_MESSAGE=1<br>
<br>
--Kiran</span></p>
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<p class="x_xmsonormal"><b><span style="color:black">From:</span></b><span style="color:black"> flang-dev <flang-dev-bounces@lists.llvm.org> on behalf of Jost, Gabriele (ARC-TNC)[Supersmith] via flang-dev <flang-dev@lists.llvm.org><br>
<b>Sent:</b> 18 April 2020 22:56<br>
<b>To:</b> flang-dev@lists.llvm.org <flang-dev@lists.llvm.org><br>
<b>Subject:</b> [flang-dev] arm + denormals</span> </p>
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<p class="x_xxmsonormal"><span style="font-size:11.0pt">Hello,</span></p>
<p class="x_xxmsonormal"><span style="font-size:11.0pt">I am running into the problem that flang checks to see if they are denormals. If it thinks they are denormals, it prints out a warning. That slows down the runtime a lot.</span></p>
<p class="x_xxmsonormal"><span style="font-size:11.0pt">Other folks have compiled the same code with ifort using -ftz, probably because they are not concerned about underflows. Is there something similar available for flang, to avoid the checking/printing warnings?</span></p>
<p class="x_xxmsonormal"><span style="font-size:11.0pt">Thanks and greetings,</span></p>
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<p class="x_xxmsonormal"><span style="font-size:10.5pt; color:black">Gabriele Jost</span></p>
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<p class="x_xxmsonormal"><span style="font-size:10.5pt; color:black">Gabriele Jost NASA Ames Research Center</span></p>
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