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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">OK. It seems like whatever generated that sh_entsize value for i386 is wrong, but I suppose it’s best to handle it as you have anyway.<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 only problem I see with your patch is that according to the ELF spec zero is a valid value for sh_addralign, and if you pass that to llvm::RoundUpToAlignment
it will get a divide-by-zero error. If you check for zero and substitute 1 in that case it should be good to commit.<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">-Andy<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"><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""> Michael Sartain [mailto:mikesart@gmail.com]
<br>
<b>Sent:</b> Friday, August 16, 2013 4:35 PM<br>
<b>To:</b> Kaylor, Andrew<br>
<b>Cc:</b> Greg Clayton; lldb-dev@cs.uiuc.edu<br>
<b>Subject:</b> Re: lldb test failures on 32bit<o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">> As for your patch, am I correct in thinking that I should ignore the history in that review? <o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Yeah, sorry. I need to clear arc out.<br>
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> Can you explain the change to me? What values were you seeing for sh_entsize and sh_addralign?<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 x64, both were 16. On i386, entsize was 4, addralign was 16. The size of the .plt entries are 16 in each case.<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Thanks!<br>
<br>
On Friday, August 16, 2013, Kaylor, Andrew wrote:<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Hi Mike,</span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"> </span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">A variation of reloc-fix-32.patch was committed today by Richard Mitton.</span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"> </span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">I need to do something with stack-fix-32.patch. If I’m reading the documentation correctly, it appears
that stack frames really do need to be 8-byte aligned in Darwin even for 32-bit code.</span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"> </span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Unfortunately, we’re using the same ABI plugin for 32-bit x86 code on Darwin and Linux and at the
level where this check is performed we don’t know which we’re looking at. As far as I know, there really isn’t a significant difference between the two scenarios, so I don’t think we’d want a totally separate ABI plug-in. I just need to see if there’s an
easy way to give it a little target information when it’s created so it can handle the special cases.</span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"> </span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">As for your patch, am I correct in thinking that I should ignore the history in that review? Can
you explain the change to me? What values were you seeing for sh_entsize and sh_addralign?</span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"> </span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">-Andy</span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"> </span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><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""> Michael Sartain [mailto:<a href="javascript:_e(%7b%7d,%20'cvml',%20'mikesart@gmail.com');" target="_blank">mikesart@gmail.com</a>]
<br>
<b>Sent:</b> Thursday, August 15, 2013 1:07 PM<br>
<b>To:</b> Greg Clayton; Kaylor, Andrew<br>
<b>Cc:</b> <a href="javascript:_e(%7b%7d,%20'cvml',%20'lldb-dev@cs.uiuc.edu');" target="_blank">
lldb-dev@cs.uiuc.edu</a><br>
<b>Subject:</b> Re: [lldb-dev] lldb test failures on 32bit</span><o:p></o:p></p>
<p> <o:p></o:p></p>
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<p>I realized Andrew's reloc-fix-32.patch & stack-fix-32.patch weren't checked in and I didn't have them. Applying both of those with my patch below allows me to step over the 32-bit printf() calls now.<o:p></o:p></p>
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<p> <o:p></o:p></p>
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<p>Are those patches what you hope to check in at some point Andrew?<o:p></o:p></p>
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<p> <o:p></o:p></p>
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<p>And please let me know if it's ok to check this in:<o:p></o:p></p>
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<p> <o:p></o:p></p>
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<p><a href="http://llvm-reviews.chandlerc.com/D1189" target="_blank">http://llvm-reviews.chandlerc.com/D1189</a><o:p></o:p></p>
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<p> <o:p></o:p></p>
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<p>Thanks!<o:p></o:p></p>
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<p> -Mike<o:p></o:p></p>
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<p> <o:p></o:p></p>
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<p>On Thu, Aug 15, 2013 at 10:39 AM, Michael Sartain <<a href="mailto:mikesart@gmail.com">mikesart@gmail.com</a>> wrote:<o:p></o:p></p>
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<p>On Tue, Aug 13, 2013 at 6:22 PM, Michael Sartain <<a href="mailto:mikesart@gmail.com">mikesart@gmail.com</a>> wrote:<o:p></o:p></p>
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<p>Unwind info does exist for addresses in main(), and all of this works as expected in x64.<o:p></o:p></p>
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<p> <o:p></o:p></p>
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<p>I'll start debugging where this is failing...<o:p></o:p></p>
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<p> <o:p></o:p></p>
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<p>For x86 elf files, the plt_entsize wasn't being rounded to the proper alignment - this was causing the .plt symbols to be incorrect, along with unwind info, etc. This patch fixes that:<o:p></o:p></p>
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<p> <o:p></o:p></p>
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<p><a href="http://llvm-reviews.chandlerc.com/D1189" target="_blank">http://llvm-reviews.chandlerc.com/D1189</a><o:p></o:p></p>
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<p> <o:p></o:p></p>
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<p>The next problem is we're using the x64 register set, but then calling into the i386 ABI. Ie, this call:<o:p></o:p></p>
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<p> <o:p></o:p></p>
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<p> 246| addr_t pc;<o:p></o:p></p>
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<p> 247+> if (!ReadGPRValue (eRegisterKindGeneric, LLDB_REGNUM_GENERIC_PC, pc))<o:p></o:p></p>
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<p> 248| {<o:p></o:p></p>
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<p> <o:p></o:p></p>
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<p>Winds up here:<o:p></o:p></p>
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<p> <o:p></o:p></p>
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<p>1092| ExecutionContext exe_ctx(m_thread.shared_from_this());<o:p></o:p></p>
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<p>1093| Process *process = exe_ctx.GetProcessPtr();<o:p></o:p></p>
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<p>1094| if (have_unwindplan_regloc == false)<o:p></o:p></p>
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<p>1095| {<o:p></o:p></p>
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<p>1096| // If a volatile register is being requested, we don't want to forward the next frame's register contents<o:p></o:p></p>
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<p>1097| // up the stack -- the register is not retrievable at this frame.<o:p></o:p></p>
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<p>1098| ABI *abi = process ? process->GetABI().get() : NULL;<o:p></o:p></p>
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<p>1099| if (abi)<o:p></o:p></p>
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<p>1100| {<o:p></o:p></p>
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<p>1101+> const RegisterInfo *reg_info = GetRegisterInfoAtIndex(lldb_regnum);<o:p></o:p></p>
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<p>1102| if (reg_info && abi->RegisterIsVolatile (reg_info))<o:p></o:p></p>
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<p>1103| {<o:p></o:p></p>
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<p>1104| UnwindLogMsg ("did not supply reg location for %d (%s) because it is volatile",<o:p></o:p></p>
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<p>1105| lldb_regnum, reg_info->name ? reg_info->name : "??");<o:p></o:p></p>
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