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<p class="MsoNormal">Hi,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I am building a minikernel of the 4 x N kernel and testing it in different architectures. Currently I am trying with in an ARMv8 with Advanced NEON using double-FP.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I see that this kernel operates with 4 particles at the time. When I use double-FP I can fill each SIMD unit with 2 FP numbers (128 bits long for Advanced NEON). I checked that that some interactions in this kernel between the 4 particles
are not performed: particle 3 and 4 have net force = 0 (in this minikernel). Am I losing something here? Is the kernel prepared to operate in double precision for vector lengths of 128 bits? Is the masking mechanism intended to solve this issue?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Note: when I use single-FP the 4 forces are different from 0 as I expected.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Thanks a lot for the help ;) <o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><b><span style="font-size:10.0pt;color:#666666">Best regards | Mit freundlichen Grüßen</span></b><span style="font-size:10.0pt;color:#666666"><o:p></o:p></span></p>
<p class="MsoNormal"><b><span style="font-size:10.0pt;color:#666666"><o:p> </o:p></span></b></p>
<p class="MsoNormal"><b><span style="font-size:10.0pt;color:#666666">Guido Giuntoli</span></b><b><span style="font-size:10.0pt;color:#1F497D"><o:p></o:p></span></b></p>
<p class="MsoNormal"><b><span style="font-size:10.0pt;color:#666666"><o:p> </o:p></span></b></p>
<p class="MsoNormal">HUAWEI TECHNOLOGIES Duesseldorf GmbH<br>
Hansaallee 205, 40549 Dusseldorf, Germany, <a href="http://www.huawei.com/"><b><span style="color:blue">www.huawei.com</span></b></a><br>
Registered Office: Düsseldorf, Register Court Düsseldorf, HRB 56063, <br>
Managing Director: Li Peng, Li Jian, Shi Yanli<b><span style="font-size:8.0pt;font-family:"Arial",sans-serif;color:gray"><o:p></o:p></span></b></p>
<p class="MsoNormal"><span lang="DE">Sitz der Gesellschaft: Düsseldorf, Amtsgericht Düsseldorf, HRB 56063,
<br>
Geschäftsführer: Li Peng, Li Jian, Shi Yanli<o:p></o:p></span></p>
<p class="MsoNormal"><b><span lang="EN-GB" style="font-size:9.0pt">-----------------------------------------------------------------------------------------------</span></b><span style="color:#1F497D"><o:p></o:p></span></p>
<p class="MsoNormal"><b><span style="font-size:9.0pt">This e-mail and its attachments contain confidential information from HUAWEI, which is intended only for the person or entity whose address is listed above. Any use of the information contained herein in
any way (including, but not limited to, total or partial disclosure, reproduction, or dissemination) by persons other than the intended recipient(s) is prohibited. If you receive this e-mail in error, please notify the sender by phone or email immediately
and delete it!</span></b><b><o:p></o:p></b></p>
<p class="MsoNormal"><o:p> </o:p></p>
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