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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Read the code assuming useAllLinkageNames() is false. Then recognize that we go through applySubprogramDefinitionAttributes for both declarations and definitions
(don't blame me, it was like that when I found it).<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">When we go through here for the declaration, there's no prior declaration, so SPDecl is null. DeclLinkageName is empty, useAllLinkageNames() is false, and
getAbstractSPDies() also returns nothing. So the declaration does not get a linkage name.<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">When we come through for the definition, there is a prior declaration, so SPDecl points to it (i.e. the metadata). DeclLinkageName is non-empty, because the
declaration metadata does have a linkage name. Therefore we once again do not emit the linkage name.<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">After the patch, when we come through for the definition, there is a prior declaration, so SPDecl points to the metadata. But the declaration DIE doesn't have
a linkage-name attribute, so DeclLinkageName is empty. This allows us to emit the linkage name on the definition (which is the abstract origin).<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">The same thing will be true in the updated patch I'm about to upload, but we won't be looking into the DIE to figure it out.<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-commits [mailto:llvm-commits-bounces@lists.llvm.org]
<b>On Behalf Of </b>David Blaikie via llvm-commits<br>
<b>Sent:</b> Thursday, December 01, 2016 1:50 PM<br>
<b>To:</b> reviews+D27320+public+0ef1c083eb06e109@reviews.llvm.org; echristo@gmail.com; aprantl@apple.com<br>
<b>Cc:</b> llvm-commits@lists.llvm.org<br>
<b>Subject:</b> Re: [PATCH] D27320: [DWARF] Put linkage-name on abstract origin even when there's a declaration<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">Reading the actual code - I'm now a bit confused. It looks like it's duplicating the linkage name but I thought the patch description was saying it was missing from the declaration.<br>
<br>
I'm confused.<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">On Thu, Dec 1, 2016 at 1:44 PM Paul Robinson via Phabricator <<a href="mailto:reviews@reviews.llvm.org">reviews@reviews.llvm.org</a>> wrote:<o:p></o:p></p>
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<p class="MsoNormal" style="margin-bottom:12.0pt">probinson added inline comments.<br>
<br>
<br>
================<br>
Comment at: lib/CodeGen/AsmPrinter/DwarfUnit.cpp:1162<br>
"getOrCreateSubprogramDIE");<br>
- DeclLinkageName = SPDecl->getLinkageName();<br>
+ DeclLinkageName = getDieLinkageName(DeclDie);<br>
unsigned DeclID =<br>
----------------<br>
I had thought about making this<br>
```<br>
if (DD->useAllLinkageNames())<br>
DeclLinkageName = SPDecl->getLinkageName();<br>
```<br>
and so not needing the extra static function, but actually looking into the DIE itself seemed more robust.<br>
<br>
<br>
<a href="https://reviews.llvm.org/D27320" target="_blank">https://reviews.llvm.org/D27320</a><br>
<br>
<br>
<o:p></o:p></p>
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