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<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Verdana",sans-serif;color:#1F497D;mso-fareast-language:EN-US">I think we are all in agreement.
<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Verdana",sans-serif;color:#1F497D;mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Verdana",sans-serif;color:#1F497D;mso-fareast-language:EN-US">Daniel is just pointing out that the compiler should be optimizing the case where the user implied the unneeded barrier (by writing</span><span style="font-size:10.0pt;font-family:"Lucida Console";color:#1F497D;mso-fareast-language:EN-US">
omp parallel {omp for/do {}}), </span><span style="font-size:10.0pt;font-family:"Verdana",sans-serif;color:#1F497D;mso-fareast-language:EN-US">and that if it does that down the line, it’s safe for the front-end to do the
</span><span style="font-size:10.0pt;font-family:"Lucida Console";color:#1F497D;mso-fareast-language:EN-US">omp parallel for => omp parallel { omp for {} }</span><span style="font-size:10.0pt;font-family:"Verdana",sans-serif;color:#1F497D;mso-fareast-language:EN-US">
transformation.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Lucida Console";color:#1F497D;mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Verdana",sans-serif;color:#1F497D">-- Jim<br>
<br>
Jim Cownie <james.h.cownie@intel.com><br>
SSG/DPD/TCAR (Technical Computing, Analyzers, and Runtimes)<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Verdana",sans-serif;color:#1F497D">Tel: +44 117 9071438</span><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Verdana",sans-serif;color:#1F497D;mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><b><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri",sans-serif">From:</span></b><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri",sans-serif"> C Bergström [mailto:cbergstrom@pathscale.com]
<br>
<b>Sent:</b> Friday, June 9, 2017 3:39 PM<br>
<b>To:</b> Daniel Schürmann <daniel.schuermann@campus.tu-berlin.de><br>
<b>Cc:</b> Cownie, James H <james.h.cownie@intel.com>; openmp-dev@lists.llvm.org<br>
<b>Subject:</b> Re: [Openmp-dev] Proposal: Resolve combined directives in parsing phase<o:p></o:p></span></p>
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<p class="MsoNormal" style="margin-bottom:12.0pt">James is really clear on the point of "AS-IF" - The compiler can do anything as long as the user can't observe a difference in the behavior. The standard can say add a barrier, but if the compiler can make the
code visibly act the same with our without a barrier that's all that matters.<br>
<br>
<o:p></o:p></p>
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