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<p>Please put it as review in Phabricator so others can comment too. I am wondering how we can test this behaviour.<br>
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<p>One can use -fno-asynchronous-unwind-tables with clang to disable generation of .eh_frame but the startup code<br>
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<p>still brings in that section. <br>
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<p>You also need to run clang-format to make sure formatting is right and I see some strange characters in the patch file.<br>
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<p>> + // Try to find .debug_frame section even if .eh_frame doesn't exist. <br>
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<p>s/<span style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 16px; background-color: rgb(255, 255, 255);">even if</span>/if/<br>
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<p>Thanks,<br>
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<p>Abid<br>
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<div id="divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" color="#000000" style="font-size:11pt"><b>From:</b> Tatyana Krasnukha <Tatyana.Krasnukha@synopsys.com><br>
<b>Sent:</b> Tuesday, May 23, 2017 6:20 PM<br>
<b>To:</b> Abid, Hafiz; lldb-commits@lists.llvm.org<br>
<b>Subject:</b> RE: [Lldb-commits] Patch for fixing FDE indexing when scan debug_info section</font>
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<p class="MsoNormal">Done. I have also added a little change which allow to use debug_info section when eh_frame is absent. This case really can take place on some platforms.</p>
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<p class="MsoNormal">Thanks,</p>
<p class="MsoNormal">Tatyana</p>
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<p class="MsoNormal"><b>From:</b> Abid, Hafiz [mailto:Hafiz_Abid@mentor.com] <br>
<b>Sent:</b> Tuesday, 23 May, 2017 3:31 PM<br>
<b>To:</b> Tatyana Krasnukha <Tatyana.Krasnukha@synopsys.com>; lldb-commits@lists.llvm.org<br>
<b>Subject:</b> Re: [Lldb-commits] Patch for fixing FDE indexing when scan debug_info section</p>
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<p class="MsoNormal"><span style="font-size:12.0pt; color:black">It looks ok to me. Please put the differences of .eh_frame and</span></p>
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<p class="MsoNormal"><span style="font-size:12.0pt; color:black">.debug_frame that you described below in code comments too.</span></p>
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<p class="MsoNormal"><span style="font-size:12.0pt; color:black">Thanks,</span></p>
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<p class="MsoNormal"><span style="font-size:12.0pt; color:black">Abid</span></p>
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<p><span style="font-family:"Calibri",sans-serif; color:black"> </span></p>
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<p class="MsoNormal"><b><span style="color:black">From:</span></b><span style="color:black"> lldb-commits <<a href="mailto:lldb-commits-bounces@lists.llvm.org">lldb-commits-bounces@lists.llvm.org</a>> on behalf of Tatyana Krasnukha via lldb-commits <<a href="mailto:lldb-commits@lists.llvm.org">lldb-commits@lists.llvm.org</a>><br>
<b>Sent:</b> Thursday, May 18, 2017 9:37 PM<br>
<b>To:</b> <a href="mailto:lldb-commits@lists.llvm.org">lldb-commits@lists.llvm.org</a><br>
<b>Subject:</b> [Lldb-commits] Patch for fixing FDE indexing when scan debug_info section</span><span style="font-size:12.0pt; color:#212121">
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<p class="MsoNormal"><span style="color:#212121">Fix FDE indexing while scan debug_info section.</span></p>
<p class="MsoNormal"><span style="color:#212121"> </span></p>
<p class="MsoNormal"><span style="color:#212121">There are some </span><span style="color:black">differences between eh_frame and debug_frame formats that are not considered by
</span><span style="font-size:9.5pt; font-family:Consolas; color:#2B91AF">DWARFCallFrameInfo</span><span style="font-size:9.5pt; font-family:Consolas; color:black">::GetFDEIndex</span><span style="color:black">.</span><span style="color:#212121"></span></p>
<p class="MsoNormal"><span style="color:black">An FDE entry contains </span><span style="color:#212121">CIE_pointer
</span><span style="color:black">in debug_frame in same place as cie_id in eh_frame. As described in
<a href="https://urldefense.proofpoint.com/v2/url?u=http-3A__www.dwarfstd.org_doc_dwarf-2D2.0.0.pdf&d=DwMFAw&c=DPL6_X_6JkXFx7AXWqB0tg&r=yfnu24japkhNGh-WqJObHXmH3mINtC_2FO828lrNpM0&m=6bXYUUYhGtSz4V-aPy_DuviU1kYtmn9rHUU-2aIGDzE&s=kMPV12z6OBKSq3lC8HgNgMkv23SamtORaFALS-I-Vts&e=">
dwarf standard</a> (section 6.4.1),</span><span style="color:#212121"></span></p>
<p class="MsoNormal"><span style="color:#212121">CIE_pointer is an “offset into the .debug_frame section”. So, variable cie_offset should be equal
</span><span style="color:black">cie_id for debug_frame.</span><span style="color:#212121"></span></p>
<p class="MsoNormal"><span style="color:black">FDE entries with zeroth CIE pointer (which is actually placed in
</span><span style="color:#212121">cie_id variable</span><span style="color:black">) shouldn’t be ignored also.</span><span style="color:#212121"></span></p>
<p class="MsoNormal"><span style="color:black"> </span><span style="color:#212121"></span></p>
<p class="MsoNormal"><span style="color:black">I had same issue as described here
<a href="https://urldefense.proofpoint.com/v2/url?u=http-3A__lists.llvm.org_pipermail_lldb-2Ddev_2014-2DOctober_005520.html&d=DwMFAw&c=DPL6_X_6JkXFx7AXWqB0tg&r=yfnu24japkhNGh-WqJObHXmH3mINtC_2FO828lrNpM0&m=6bXYUUYhGtSz4V-aPy_DuviU1kYtmn9rHUU-2aIGDzE&s=7NGym3Cx6gVwlzBRE44Zm6Teee6tMi9Iq-BTRMjM6Pc&e=">
http://lists.llvm.org/pipermail/lldb-dev/2014-October/005520.html</a> , and these changes have fixed it for me (with "m_is_eh_frame" set to false, of course).
</span><span style="color:#212121"></span></p>
<p class="MsoNormal"><span style="font-family:"Courier New"; color:#212121"> </span><span style="color:#212121"></span></p>
<p class="MsoNormal"><b><span style="font-size:10.0pt; font-family:"Arial",sans-serif; color:#212121">Tatyana Krasnukha</span></b><span style="color:#212121"></span></p>
<p class="MsoNormal"><span style="font-size:9.0pt; font-family:"Arial",sans-serif; color:#212121">Software Engineer, Sr. I, Solutions Group, Synopsys Inc.</span><span style="color:#212121"></span></p>
<p class="MsoNormal"><span style="font-size:9.0pt; font-family:"Arial",sans-serif; color:#212121">w +7.812.408.7463 | m +7 981 757-4491 |
</span><span style="color:#212121"><a href="mailto:tatyana@synopsys.com"><span style="font-size:9.0pt; font-family:"Arial",sans-serif; color:blue">tatyana@synopsys.com</span></a></span></p>
<p class="MsoNormal"><span style="color:#212121"> </span></p>
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