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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Abstractly, (I don't get inside this code as much as I should) debug info works on a translation-unit basis, not a function basis, so regenerating a single
function's debug info is not a natural or well-isolated operation.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">You might have to emit each function as its own LLVM module and re-JIT the module?<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">People more deeply familiar with how the metadata stuff works might be able to offer better suggestions.<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>deadal nix via llvm-dev<br>
<b>Sent:</b> Friday, October 02, 2015 11:38 PM<br>
<b>To:</b> llvm-dev<br>
<b>Subject:</b> [llvm-dev] Editing metadata<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" style="margin-bottom:12.0pt">Hi all,<o:p></o:p></p>
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<p class="MsoNormal">I'm using the JIT capabilities of LLVM. But so far, I've been unable to use the debug capabilities of LLVM in conjunction with the JIT. The problematic scenario goes as follow :<o:p></o:p></p>
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<p class="MsoNormal"> - Emit some IR with debug infos.<o:p></o:p></p>
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<p class="MsoNormal"> - Install hooks to get back into some codepath that I do not wish to codegen at this stage.<o:p></o:p></p>
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<p class="MsoNormal"> - JIT the method. This require to finalize the DIBuilder to complete the emission of debug metadata.<o:p></o:p></p>
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<p class="MsoNormal"> - Later on, emit IR for some of the missing branches. Here the problem surface :<o:p></o:p></p>
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<p class="MsoNormal"> - Without debug infos, the codegen for this specific method can be invalidated and redone, all is fine.<o:p></o:p></p>
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<p class="MsoNormal" style="margin-bottom:12.0pt"> - With debug infos, the metadata have been finalized already, and it doesn't seems that it is possible to revert this<o:p></o:p></p>
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<p class="MsoNormal" style="margin-bottom:12.0pt">Is there a way to make that work ? If not, is there a patch I can work on to make that work ?<o:p></o:p></p>
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<p class="MsoNormal">Thank in advance,<o:p></o:p></p>
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