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<p class="MsoNormal">Probably you want to a pass to transform select instructions to control flow late, after optimizations have run. Trying to prevent clang IR generation and IR optimizations from forming selects is way too difficult.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I don’t think this transform exists as an independent pass, but you can borrow code from CodeGenPrepare::optimizeSelectInst.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">-Eli<o:p></o:p></p>
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<p class="MsoNormal"><b>From:</b> llvm-dev <llvm-dev-bounces@lists.llvm.org> <b>On Behalf Of
</b>Robert Henry via llvm-dev<br>
<b>Sent:</b> Thursday, August 1, 2019 4:54 PM<br>
<b>To:</b> llvm-dev@lists.llvm.org<br>
<b>Subject:</b> [EXT] [llvm-dev] how to generate select-free LLVM IR?<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal"><span style="font-size:12.0pt;color:black">I run "clang ... --emit-llvm ....". I get LLVM IR select instructions out. I don't want select instructions, but want explicit control flow.<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:12.0pt;color:black"><o:p> </o:p></span></p>
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<p class="MsoNormal"><span style="font-size:12.0pt;color:black">Is there a way to do this?<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:12.0pt;color:black"><o:p> </o:p></span></p>
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<p class="MsoNormal"><span style="font-size:12.0pt;color:black">I'm scared of disabling the SimplifyCFG pass since it appears to do much more than just rewrite to use select statements.<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:12.0pt;color:black"><o:p> </o:p></span></p>
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