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<p class="MsoNormal">Have you read <a href="http://llvm.org/docs/CodeGenerator.html#instruction-selection-section">
http://llvm.org/docs/CodeGenerator.html#instruction-selection-section</a> ? That covers the general DAG representation and the meaning of a “chain”.<o:p></o:p></p>
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<p class="MsoNormal">In general, if you don’t understand how something in SelectionDAG is supposed to work, I’d suggest looking at other targets, and using the dumping options frequently.<o:p></o:p></p>
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<p class="MsoNormal">-Eli<o:p></o:p></p>
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<p class="MsoNormal" style="margin-left:.5in"><b>From:</b> llvm-dev <llvm-dev-bounces@lists.llvm.org>
<b>On Behalf Of </b>jeniffer lesley via llvm-dev<br>
<b>Sent:</b> Saturday, August 1, 2020 10:35 AM<br>
<b>To:</b> llvm-dev@lists.llvm.org<br>
<b>Subject:</b> [EXT] [llvm-dev] Understanding assert in SelectionDAGBuilder.cpp<o:p></o:p></p>
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<p class="MsoNormal" style="margin-left:.5in">Hi,<o:p></o:p></p>
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<p class="MsoNormal" style="margin-left:.5in">I am new to LLVM. I am experimenting with a toy backend. I don't understand
<o:p></o:p></p>
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<p class="MsoNormal" style="margin-left:.5in">"LowerFormalArguments didn't return a valid chain" in SelectionDAGBuilder.cpp file. What is the interface here? What does it mean by returning a Chain?<o:p></o:p></p>
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<p class="MsoNormal" style="margin-left:.5in"><o:p> </o:p></p>
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<p class="MsoNormal" style="margin-left:.5in">Thanks<o:p></o:p></p>
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<p class="MsoNormal" style="margin-left:.5in">Jen. <o:p></o:p></p>
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<p class="MsoNormal" style="margin-left:.5in"><o:p> </o:p></p>
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