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<p class="MsoNormal"><a name="_MailEndCompose"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">We are also thinking about necessity of horizontal intrinsics : sum, mul, min, max – for floating point and integers, and logical operations
for integers.<o:p></o:p></span></a></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">It will allow to apply target specific optimizations for reduction tail.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"><o:p> </o:p></span></p>
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<p class="MsoNormal" style="margin-left:36.0pt;text-indent:-18.0pt;mso-list:l0 level1 lfo1">
<![if !supportLists]><span style="font-family:"Calibri",sans-serif;color:#2F5496"><span style="mso-list:Ignore">-<span style="font:7.0pt "Times New Roman"">
</span></span></span><![endif]><span dir="LTR"></span><b><i><span style="color:#2F5496"> Elena<o:p></o:p></span></i></b></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"><o:p> </o:p></span></p>
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<p class="MsoNormal"><a name="_____replyseparator"></a><b><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">From:</span></b><span style="font-size:11.0pt;font-family:"Calibri",sans-serif"> llvm-dev [mailto:llvm-dev-bounces@lists.llvm.org]
<b>On Behalf Of </b>Martin J. O'Riordan via llvm-dev<br>
<b>Sent:</b> Monday, May 16, 2016 13:11<br>
<b>To:</b> 'LLVM Developers' <llvm-dev@lists.llvm.org><br>
<b>Subject:</b> Re: [llvm-dev] sum elements in the vector<o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><span lang="EN-IE" style="font-family:"Book Antiqua",serif;color:#1F497D">This would be really cool. We have several instructions that perform horizontal vector operations, and have to use built-ins to select them as there is no easy way
of expressing them in a TD file. Some like SUM for a ‘</span><span lang="EN-IE" style="font-family:"Courier New";color:black">v4i32</span><span lang="EN-IE" style="font-family:"Book Antiqua",serif;color:#1F497D">’ are easy enough to express with a pattern
fragment, SUM ‘</span><span lang="EN-IE" style="font-family:"Courier New";color:black">v8i16</span><span lang="EN-IE" style="font-family:"Book Antiqua",serif;color:#1F497D">’ takes TableGen a long time to compute, but SUM ‘</span><span lang="EN-IE" style="font-family:"Courier New";color:black">v16i8</span><span lang="EN-IE" style="font-family:"Book Antiqua",serif;color:#1F497D">’
resulted in TableGen disappearing into itself for hours trying to reduce the patterns before I gave up and cancelled it.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-IE" style="font-family:"Book Antiqua",serif;color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-IE" style="font-family:"Book Antiqua",serif;color:#1F497D">If there were ISD nodes for these, then it would be far simpler to express in TableGen, and also, the pattern fragments only match a very specific form of IR to the
desired instruction.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-IE" style="font-family:"Book Antiqua",serif;color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-IE" style="font-family:"Book Antiqua",serif;color:#1F497D">The horizontal operations are particularly useful for finalising a vectorised operation - for example I may want to compute the scalar MAX, MIN or SUM of a large
number of items. If the number of items is divisible by the vector lanes (e.g. 4, 8, or 16 in our case), then 4, 8 or 16 at a time can be computed using normal vector operation, and then the final scalar value can be computed using a single horizontal operation.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-IE" style="font-family:"Book Antiqua",serif;color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-IE" style="font-family:"Book Antiqua",serif;color:#1F497D"> MartinO<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-IE" style="font-family:"Book Antiqua",serif;color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><b><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">From:</span></b><span style="font-size:11.0pt;font-family:"Calibri",sans-serif"> llvm-dev [<a href="mailto:llvm-dev-bounces@lists.llvm.org">mailto:llvm-dev-bounces@lists.llvm.org</a>]
<b>On Behalf Of </b>Chandler Carruth via llvm-dev<br>
<b>Sent:</b> 16 May 2016 2:16<br>
<b>To:</b> Shahid, Asghar-ahmad; Rail Shafigulin; llvm-dev; Hal Finkel<br>
<b>Subject:</b> Re: [llvm-dev] sum elements in the vector<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-IE"><o:p> </o:p></span></p>
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<p class="MsoNormal"><span lang="EN-IE">I'm starting to think we should directly implement horizontal operations on vector types.<o:p></o:p></span></p>
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<p class="MsoNormal"><span lang="EN-IE"><o:p> </o:p></span></p>
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<p class="MsoNormal"><span lang="EN-IE">My suspicion is that coming up with a nice model for this would help us a lot with things like:<o:p></o:p></span></p>
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<p class="MsoNormal"><span lang="EN-IE">- Idiom recognition of reduction patterns that use horizontal arithmetic<o:p></o:p></span></p>
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<p class="MsoNormal"><span lang="EN-IE">- Ability to use horizontal operations in SLPVectorizer<o:p></o:p></span></p>
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<p class="MsoNormal"><span lang="EN-IE">- Significantly easier cost modeling of vectorizing loops with reductions in LoopVectorize<o:p></o:p></span></p>
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<p class="MsoNormal"><span lang="EN-IE">- Other things I've not thought of?<o:p></o:p></span></p>
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<p class="MsoNormal"><span lang="EN-IE"><br>
</span><span lang="EN-IE" style="font-family:"Helvetica",sans-serif"> Curious what others think?</span><span lang="EN-IE"><o:p></o:p></span></p>
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<p class="MsoNormal"><span lang="EN-IE"><o:p> </o:p></span></p>
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<p class="MsoNormal"><span lang="EN-IE" style="font-family:"Helvetica",sans-serif">-Chandler</span><span lang="EN-IE"><o:p></o:p></span></p>
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<p class="MsoNormal"><span lang="EN-IE"><o:p> </o:p></span></p>
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<p class="MsoNormal"><span lang="EN-IE">On Wed, May 11, 2016 at 10:07 PM Shahid, Asghar-ahmad via llvm-dev <<a href="mailto:llvm-dev@lists.llvm.org">llvm-dev@lists.llvm.org</a>> wrote:<o:p></o:p></span></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">></span> why in order to add this particular instruction (sum elements in a vector) I need to add an
insrinsic?<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Adding intrinsic is not the only way, it is one of the way and user WILL-NOT be required to invoke<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">It specifically.<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Currently LLVM does not have any instruction to directly represent “sum of elements in a vector” and<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">generate your particular instruction.However, you can do it without intrinsic by pattern matching the<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">LLVM-IRs representing “sum of elements in vector” to your particular instruction in DAGCombiner.<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Regards,<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Shahid<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"> </span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"> </span><o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><b><span style="font-size:10.0pt;font-family:"Tahoma",sans-serif">From:</span></b><span style="font-size:10.0pt;font-family:"Tahoma",sans-serif"> Rail Shafigulin [mailto:<a href="mailto:rail@esenciatech.com" target="_blank">rail@esenciatech.com</a>]
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<b>Sent:</b> Monday, May 09, 2016 11:59 PM<br>
<b>To:</b> Shahid, Asghar-ahmad; llvm-dev<br>
<b>Cc:</b> Das, Dibyendu</span><o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:10.0pt;font-family:"Tahoma",sans-serif"><br>
<b>Subject:</b> Re: [llvm-dev] sum elements in the vector</span><o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">I'm a little confused. Here is why.<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">I was able to add a vector add instruction to my target without using any intrinsics and without adding any new instructions to LLVM. So here is my question: how come I managed
to add a new vector instruction without adding an intrinsic and why in order to add this particular instruction (sum elements in a vector) I need to add an insrinsic?<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Another question that I have is whether compiler will be able to target this new instruction (sum elements in a vector) if it is implemented as an intrinsic or the user will have
to specifically invoke an instrinsic.<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Pardon if questions seem dumb, I'm still learning things.<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Any help is appreciated. <o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">On Fri, May 6, 2016 at 1:51 PM, Rail Shafigulin <<a href="mailto:rail@esenciatech.com" target="_blank">rail@esenciatech.com</a>> wrote:<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Thanks for the reply. These steps will add an instruction as an intrinsic. Is it possible to add an actual new instruction so that a compiler could target it during an optimization?
How hard is it to do it? Is that a realistic objective.<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="color:#888888">Rail</span><o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">On Mon, Apr 4, 2016 at 9:02 PM, Shahid, Asghar-ahmad <<a href="mailto:Asghar-ahmad.Shahid@amd.com" target="_blank">Asghar-ahmad.Shahid@amd.com</a>> wrote:<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">Hi Rail,</span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"> </span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">We had done this for generation of X86 PSAD (sum of absolute difference) instruction through</span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">Llvm intrinsic. Doing this requires following</span><o:p></o:p></p>
<p><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">1.</span><span style="font-size:7.0pt;color:#1F497D">
</span><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">Define an intrinsic, xyz(), for the required instruction and corresponding SDNode</span><o:p></o:p></p>
<p><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">2.</span><span style="font-size:7.0pt;color:#1F497D">
</span><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">Generate the “call xyz() “ IR based the matched pattern</span><o:p></o:p></p>
<p><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">3.</span><span style="font-size:7.0pt;color:#1F497D">
</span><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">Map “call xyz()” IR to corresponding SDNode in SelectionDagBuilder.cpp</span><o:p></o:p></p>
<p><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">4.</span><span style="font-size:7.0pt;color:#1F497D">
</span><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">Provide default expansion of the xyz() intrinsic</span><o:p></o:p></p>
<p><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">5.</span><span style="font-size:7.0pt;color:#1F497D">
</span><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">Legalize type and/or operation</span><o:p></o:p></p>
<p><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">6.</span><span style="font-size:7.0pt;color:#1F497D">
</span><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">Provide Lowering of intrinsic/SDNode to generate your target instruction</span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"> </span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">You can visit
<a href="http://llvm.org/docs/ExtendingLLVM.html" target="_blank">http://llvm.org/docs/ExtendingLLVM.html</a> for details.</span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"> </span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">Regards,</span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">Shahid
</span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"> </span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"> </span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"> </span><o:p></o:p></p>
<div style="border:none;border-left:solid blue 1.5pt;padding:0cm 0cm 0cm 4.0pt">
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<div style="border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0cm 0cm 0cm">
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><b><span style="font-size:10.0pt;font-family:"Tahoma",sans-serif">From:</span></b><span style="font-size:10.0pt;font-family:"Tahoma",sans-serif"> llvm-dev [mailto:<a href="mailto:llvm-dev-bounces@lists.llvm.org" target="_blank">llvm-dev-bounces@lists.llvm.org</a>]
<b>On Behalf Of </b>Rail Shafigulin via llvm-dev<br>
<b>Sent:</b> Monday, April 04, 2016 11:00 PM<br>
<b>To:</b> Das, Dibyendu<br>
<b>Cc:</b> <a href="mailto:llvm-dev@lists.llvm.org" target="_blank">llvm-dev@lists.llvm.org</a><br>
<b>Subject:</b> Re: [llvm-dev] sum elements in the vector</span><o:p></o:p></p>
</div>
</div>
<div>
<div>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Thanks for the pointers. I looked at hadd instructions. They seem to do very similar to what I need. Unfortunately as I said before my LLVM experience is limited. My understanding
is that when I create a new type of SDNode I need to specify a pattern for it, so that when LLVM is analyzing the code and is seeing a given pattern it would create this particular node. I'm really struggling to understand how it is done. So here are the problems
that I'm having.<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">1. How do I identify that pattern that should be used?<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">2. How do I specify a given pattern? <o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
</div>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Do you (or someone else) mind helping me out? <o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
</div>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Any help is appreciated.<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">On Mon, Apr 4, 2016 at 9:59 AM, Das, Dibyendu <<a href="mailto:Dibyendu.Das@amd.com" target="_blank">Dibyendu.Das@amd.com</a>> wrote:<o:p></o:p></p>
<div>
<div>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">This is roughly along the lines of x86 hadd* instructions though the semantics of hadd* may not exactly
match what you are looking for. This is probably more in line with x86/ARM SAD-like instructions but I don’t think llvm generates SAD without intrinsics.</span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"> </span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><b><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">From:</span></b><span style="font-size:11.0pt;font-family:"Calibri",sans-serif"> llvm-dev [mailto:<a href="mailto:llvm-dev-bounces@lists.llvm.org" target="_blank">llvm-dev-bounces@lists.llvm.org</a>]
<b>On Behalf Of </b>Rail Shafigulin via llvm-dev<br>
<b>Sent:</b> Monday, April 04, 2016 9:34 AM<br>
<b>To:</b> llvm-dev <<a href="mailto:llvm-dev@lists.llvm.org" target="_blank">llvm-dev@lists.llvm.org</a>><br>
<b>Subject:</b> [llvm-dev] sum elements in the vector</span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
<div>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">My target has an instruction that adds up all elements in the vector and stores the result in a register. I'm trying to implement it in my compiler but I'm not sure even where to
start.<o:p></o:p></p>
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<div>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
</div>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">I did look at other targets, but they don't seem to have anything like it ( I could be wrong. My experience with LLVM is limited, so if I missed it, I'd appreciate if someone could
point it out ). <o:p></o:p></p>
</div>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">My understanding is that if SDNode for such an instruction doesn't exist I have to define one. Unfortunately, I don't know how to do it. I don't even know where to start looking.
Would someone care to point me in the right direction? <o:p></o:p></p>
</div>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
</div>
<div>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Any help is appreciated.<br clear="all">
<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
</div>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">--
<o:p></o:p></p>
<div>
<div>
<div>
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<div>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Rail Shafigulin<o:p></o:p></p>
</div>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Software Engineer
<br>
Esencia Technologies<o:p></o:p></p>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><br>
<br clear="all">
<o:p></o:p></p>
<div>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
</div>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">--
<o:p></o:p></p>
<div>
<div>
<div>
<div>
<div>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Rail Shafigulin<o:p></o:p></p>
</div>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Software Engineer
<br>
Esencia Technologies<o:p></o:p></p>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
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</div>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><br>
<br clear="all">
<o:p></o:p></p>
<div>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
</div>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">--
<o:p></o:p></p>
<div>
<div>
<div>
<div>
<div>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Rail Shafigulin<o:p></o:p></p>
</div>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Software Engineer
<br>
Esencia Technologies<o:p></o:p></p>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><br>
<br clear="all">
<o:p></o:p></p>
<div>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
</div>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">--
<o:p></o:p></p>
<div>
<div>
<div>
<div>
<div>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Rail Shafigulin<o:p></o:p></p>
</div>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Software Engineer
<br>
Esencia Technologies<o:p></o:p></p>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
<p class="MsoNormal"><span lang="EN-IE">_______________________________________________<br>
LLVM Developers mailing list<br>
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<a href="http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev" target="_blank">http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev</a><o:p></o:p></span></p>
</blockquote>
</div>
</div>
</div>
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