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<p class="MsoNormal"><a name="_MailEndCompose"><span style="color:#1F497D">Hi! <o:p>
</o:p></span></a></p>
<p class="MsoNormal"><span style="color:#1F497D">Will appreciate any comments regarding this question.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
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<p class="MsoNormal"><span style="color:#1F497D">Best regards, <o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D">Artur Gainullin<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
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<p class="MsoNormal"><a name="_____replyseparator"></a><b>From:</b> Gainullin, Artur
<br>
<b>Sent:</b> Thursday, November 30, 2017 10:56 AM<br>
<b>To:</b> peter@pcc.me.uk<br>
<b>Cc:</b> llvm-dev@lists.llvm.org<br>
<b>Subject:</b> Question about visibility analysis for whole program devirtualization pass<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Hi!<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I have a question about whole program devirtualization pass. According to my understanding devirtualization is performed only for the classes that have hidden LTO visibility and this visibility is controlled by attributes in the source
level or command line options. So visibility analysis is currently performed only in the front-end. But LLVM has LTO internalization pass that uses information from the linker to mark symbols as internal if it is possible. Have you ever considered to make
an analysis of visibility at this level (after internalization pass)? Or it is not possible for some reasons?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Best regards, <o:p></o:p></p>
<p class="MsoNormal">Artur Gainullin<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
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