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<p class="MsoNormal"><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.<o:p></o:p></span></p>
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<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 [mailto:llvm-dev-bounces@lists.llvm.org]
<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 <llvm-dev@lists.llvm.org><br>
<b>Subject:</b> [llvm-dev] sum elements in the vector<o:p></o:p></span></p>
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<p class="MsoNormal">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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<p class="MsoNormal">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>
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<p class="MsoNormal">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>
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<p class="MsoNormal">Any help is appreciated.<br clear="all">
<o:p></o:p></p>
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<p class="MsoNormal">-- <o:p></o:p></p>
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<p class="MsoNormal">Rail Shafigulin<o:p></o:p></p>
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<p class="MsoNormal">Software Engineer <br>
Esencia Technologies<o:p></o:p></p>
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