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<p class="MsoNormal" style="margin-left:.5in">If the sanitizers already rely on the debug info line table, which<br>
already has a file table, why can't frame layout descriptions use<br>
that as well?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal" style="margin-left:4.8pt">the frame layout descriptions contain names of the local variables, which are not part of line tables.<o:p></o:p></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"><a name="_MailEndCompose"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Sorry, I was not clear, but I was actually responding to this statement:<o:p></o:p></span></a></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">> Frame layout<br>
> descriptions encode line numbers for local variable declarations. They<br>
> don't include file names to keep object size under control, and we<br>
> can't really afford to add more duplicate debug info.<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"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">This suggests that omitting file info from frame layout descriptions is a problem. But surely whoever is reading the descriptions can get file info from the
line table, so there is no need to duplicate that info—in short, why is this a problem in frame layouts?<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">I assume you build your own frame layout descriptions because you want to work with –gmlt info instead of requiring full –g info? If you have full –g then
the variable info is in the .debug_info section already.<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>
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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""> Kostya Serebryany [mailto:kcc@google.com]
<br>
<b>Sent:</b> Thursday, December 08, 2016 9:35 AM<br>
<b>To:</b> Robinson, Paul<br>
<b>Cc:</b> Evgenii Stepanov; llvm-dev@lists.llvm.org<br>
<b>Subject:</b> Re: [llvm-dev] Debug Locations for Optimized Code<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">On Wed, Dec 7, 2016 at 5:49 PM, Robinson, Paul <<a href="mailto:paul.robinson@sony.com" target="_blank">paul.robinson@sony.com</a>> wrote:<o:p></o:p></p>
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<br>
> -----Original Message-----<br>
> From: Evgenii Stepanov [mailto:<a href="mailto:eugeni.stepanov@gmail.com">eugeni.stepanov@gmail.com</a>]<br>
> Sent: Wednesday, December 07, 2016 4:51 PM<br>
> To: Kostya Serebryany<br>
> Cc: Robinson, Paul; <a href="mailto:llvm-dev@lists.llvm.org">llvm-dev@lists.llvm.org</a><br>
> Subject: Re: [llvm-dev] Debug Locations for Optimized Code<br>
><br>
> In fact, we are already using "parallel" debug info. Frame layout<br>
> descriptions encode line numbers for local variable declarations. They<br>
> don't include file names to keep object size under control, and we<br>
> can't really afford to add more duplicate debug info.<br>
><br>
> On Wed, Dec 7, 2016 at 1:44 PM, Kostya Serebryany via llvm-dev<br>
> <<a href="mailto:llvm-dev@lists.llvm.org">llvm-dev@lists.llvm.org</a>> wrote:<br>
> > my 2c.<br>
> ><br>
> > the sanitizers rely on debug info to produce human-readable error<br>
> messages,<br>
<br>
If the sanitizers already rely on the debug info line table, which<br>
already has a file table, why can't frame layout descriptions use<br>
that as well?<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">the frame layout descriptions contain names of the local variables, which are not part of line tables.<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal" style="margin-bottom:12.0pt">--paulr<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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