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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">I'm not as familiar with all the ins and outs of metadata as maybe I should be, but ultimately the inlined function should have a DWARF description contained
within the description of the caller (which is why you're seeing the call to constructAbstractSubprogramScopeDIE). That suggests that the DISubprogram for the inlined function ought to remain, and its scope should be the DICompileUnit.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">--paulr<o:p></o:p></span></p>
<p class="MsoNormal"><a name="_MailEndCompose"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></a></p>
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<p class="MsoNormal"><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:llvm-dev-bounces@lists.llvm.org]
<b>On Behalf Of </b>Arsen Hakobyan via llvm-dev<br>
<b>Sent:</b> Friday, January 12, 2018 1:57 AM<br>
<b>To:</b> llvm-dev@lists.llvm.org<br>
<b>Subject:</b> [llvm-dev] StripDeadDebugInfo for static inline functions.<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">Hi 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">I would like to understand the strip-dead-debug-info transformation. <o:p></o:p></p>
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<p class="MsoNormal">In my test case there is a static inline function with two local variables.<o:p></o:p></p>
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<p class="MsoNormal">It appears that the function is already inlined before strip-dead-debug-info starts its work. As a result the DICompileUnit is cleaned and its subprograms list has no reference to the DISubprogram for the inlined function, but as there
is reference from the DILocalVariables to the DISubprogram it remains (IMHO).<o:p></o:p></p>
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<p class="MsoNormal">This caused to a segmentation fault while running llc on the optimized IR file at function "constructAbstractSubprogramScopeDIE" in file DwarfDebug.cpp because the scope of the DISubprogram is null (I assume it should be the DICompileUnit).<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">So I would like to know what would be the correct solution for this issue: Update optimization to not remove reference from the subprograms list, or to skip finding scope in llc.<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Any help is highly appreciated.<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Thanks,<o:p></o:p></p>
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<p class="MsoNormal">Arsen<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">-- <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="color:#444444">If it's not fun you're not doing it right -- Fran Tarkenton</span><o:p></o:p></p>
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