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<p class="MsoNormal"><a name="_MailEndCompose"><span style="font-size:10.0pt;font-family:"Verdana",sans-serif;color:#1F497D;mso-fareast-language:EN-US">Chandler,<o:p></o:p></span></a></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">That raises a more meta-question for me, which is “Why should StreamExecutor be in LLVM at all?”<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">AFAICS, with you approach<o:p></o:p></span></p>
<p class="MsoListParagraph" style="text-indent:-18.0pt;mso-list:l0 level1 lfo1"><![if !supportLists]><span style="font-size:10.0pt;font-family:Symbol;color:#1F497D;mso-fareast-language:EN-US"><span style="mso-list:Ignore">·<span style="font:7.0pt "Times New Roman"">
</span></span></span><![endif]><span style="font-size:10.0pt;font-family:"Verdana",sans-serif;color:#1F497D;mso-fareast-language:EN-US">It is not a runtime library whose interface the compiler needs to understand.<o:p></o:p></span></p>
<p class="MsoListParagraph" style="text-indent:-18.0pt;mso-list:l0 level1 lfo1"><![if !supportLists]><span style="font-size:10.0pt;font-family:Symbol;color:#1F497D;mso-fareast-language:EN-US"><span style="mso-list:Ignore">·<span style="font:7.0pt "Times New Roman"">
</span></span></span><![endif]><span style="font-size:10.0pt;font-family:"Verdana",sans-serif;color:#1F497D;mso-fareast-language:EN-US">It does not depend on any LLVM runtime libraries.<o:p></o:p></span></p>
<p class="MsoListParagraph" style="text-indent:-18.0pt;mso-list:l0 level1 lfo1"><![if !supportLists]><span style="font-size:10.0pt;font-family:Symbol;color:#1F497D;mso-fareast-language:EN-US"><span style="mso-list:Ignore">·<span style="font:7.0pt "Times New Roman"">
</span></span></span><![endif]><span style="font-size:10.0pt;font-family:"Verdana",sans-serif;color:#1F497D;mso-fareast-language:EN-US">It is expected to be used with out-of-tree plugins.<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">If I got all of that right, what connection does it have with LLVM that makes having it in the LLVM tree necessary, or an improvement
over simply having it on github (or whatever your favourite open-source hosting location is)?<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">Did I misunderstand something?<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">-- Jim<br>
<br>
James 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"> Chandler Carruth [mailto:chandlerc@google.com]
<br>
<b>Sent:</b> Tuesday, March 15, 2016 10:44 AM<br>
<b>To:</b> Jason Henline <jhen@google.com>; C Bergström <cbergstrom@pathscale.com>; Cownie, James H <james.h.cownie@intel.com><br>
<b>Cc:</b> llvm-dev <llvm-dev@lists.llvm.org>; cfe-dev <cfe-dev@lists.llvm.org>; openmp-dev@lists.llvm.org<br>
<b>Subject:</b> Re: [cfe-dev] [Openmp-dev] RFC: Proposing an LLVM subproject for parallelism runtime and support libraries<o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal" style="margin-bottom:10.0pt">On Mon, Mar 14, 2016 at 6:51 PM Jason Henline via cfe-dev <<a href="mailto:cfe-dev@lists.llvm.org">cfe-dev@lists.llvm.org</a>> wrote:<o:p></o:p></p>
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<p class="MsoNormal" style="margin-bottom:10.0pt">I think it would be great if StreamExecutor could use liboffload to perform its offloading under the hood. Right now offloading is handled in StreamExecutor using platform plugins, so I think it could be very
natural for us to write a plugin which basically forwards to liboffload.<o:p></o:p></p>
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<p class="MsoNormal" style="margin-bottom:10.0pt"><o:p> </o:p></p>
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<p class="MsoNormal" style="margin-bottom:10.0pt">I think that having a liboffload plugin would be nice, but I don't think we should really base everything on top of this for a few reasons:<o:p></o:p></p>
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<p class="MsoNormal" style="margin-bottom:10.0pt"><o:p> </o:p></p>
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<p class="MsoNormal" style="margin-bottom:10.0pt">1) I think we already have a nice plugin interface specifically designed to support out-of-tree platforms with StreamExecutor, and it wouldn't make a lot of sense to force them to re-implement there stuff.<o:p></o:p></p>
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<p class="MsoNormal" style="margin-bottom:10.0pt"><o:p> </o:p></p>
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<p class="MsoNormal" style="margin-bottom:10.0pt">2) Some platforms may not want or be able to use the liboffload style plugin.<o:p></o:p></p>
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<p class="MsoNormal" style="margin-bottom:10.0pt"><o:p> </o:p></p>
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<p class="MsoNormal" style="margin-bottom:10.0pt">It seems like if the OpenMP folks want to add a liboffload plugin to StreamExecutor, that would be an awesome additional platform, but I don't see why we need to force the coupling here.<o:p></o:p></p>
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<p class="MsoNormal" style="margin-bottom:10.0pt"><o:p> </o:p></p>
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<p class="MsoNormal" style="margin-bottom:10.0pt">My 2 cents.<o:p></o:p></p>
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<p class="MsoNormal" style="margin-bottom:10.0pt">-Chandler<o:p></o:p></p>
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