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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">I think you want to start from TargetMachine and then find an appropriate place to add a new interface function from there. You’ll want to pass a pointer to the
target machine to your pass’ constructor via the create function. You probably want to create your pass from TargetPassConfig::addISelPrepare(). If you look at that function you’ll find some other passes that use a TargetMachine argument.<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>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">-Andy<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"> Kevin Neal [mailto:Kevin.Neal@sas.com]
<br>
<b>Sent:</b> Tuesday, April 03, 2018 9:25 AM<br>
<b>To:</b> llvm-dev@lists.llvm.org<br>
<b>Cc:</b> Kaylor, Andrew <andrew.kaylor@intel.com><br>
<b>Subject:</b> [llvm] Query the target from an opt pass?<o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Courier New"">I'm working on the #pragma STDC FENV_ACCESS ON support, specifically<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Courier New"">the support for a strict version of the FP to unsigned int conversion.<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif"> </span><span style="font-size:11.0pt;font-family:"Courier New""><o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Courier New"">I've got a pass that runs and converts a new intrinsic into code that
<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Courier New"">uses the FP to signed int conversion code similar to how SelectionDAG<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Courier New"">handles this now. Except that SelectionDAG will let the target handle<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Courier New"">it if the target says it will.<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Courier New""> <o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Courier New"">How do I, from an "optimization" pass, query the target to see if it<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Courier New"">already has a better way of handling exactly this case? I grepped around<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Courier New"">and I didn't see anything in a pass that looked like what I need.<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Courier New""> <o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Courier New"">Oh, and the reason I did this as a pass is because I need to add branches,<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Courier New"">which means splitting basic blocks. I don't think I can do this in<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Courier New"">SelectionDAG.<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Calibri",sans-serif">--</span><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">
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</span><span style="font-size:10.0pt;font-family:"Courier New"">Kevin P. Neal<br>
SAS/C and SAS/C++ Compiler</span><span style="font-size:11.0pt;font-family:"Courier New""><o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Courier New"">Host Research and Development</span><span style="font-size:11.0pt;font-family:"Courier New""><o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Courier New"">SAS Institute, Inc.</span><span style="font-size:11.0pt;font-family:"Courier New""><o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif"> </span><span style="font-size:11.0pt;font-family:"Courier New""><o:p></o:p></span></p>
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