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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">The MachO handling isn’t always straightforward in that it has a lot of bit fields to handle while it’s also trying to accommodate the format abstractions baked
into the interfaces. The actual relocation type gets extracted in the RuntimeDyldMachO::resolveRelocation function (RuntimeDyldMachO.cpp:32) before it is passed on to the architecture-specific handlers. So the mask you mentioned is probably OK.<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 fact that this relocation type isn’t handled is, of course, the root of your problem.<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">MCJIT has grown on an as-needed basis up to now, with only the relocation types we were actually seeing being implemented. Unfortunately, I don’t know enough
about MachO to help with this one. Maybe Jim Grosbach can help?<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>
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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""> llvmdev-bounces@cs.uiuc.edu [mailto:llvmdev-bounces@cs.uiuc.edu]
<b>On Behalf Of </b>Weiss, Eran<br>
<b>Sent:</b> Tuesday, April 09, 2013 11:51 PM<br>
<b>To:</b> Jiong Wang<br>
<b>Cc:</b> llvmdev@cs.uiuc.edu<br>
<b>Subject:</b> Re: [LLVMdev] Migration from JIT to MCJIT<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"><span style="font-size:10.5pt;font-family:"Calibri","sans-serif";color:black">Thank you for the help.<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:10.5pt;font-family:"Calibri","sans-serif";color:black"><o:p> </o:p></span></p>
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<p class="MsoNormal"><span style="font-size:10.5pt;font-family:"Calibri","sans-serif";color:black">The relocation type value is anded with </span><span class="apple-style-span"><span style="font-size:8.5pt;font-family:"Menlo","serif";color:#2C2ECF">0xffffffffL</span></span><span style="font-size:10.5pt;font-family:"Calibri","sans-serif";color:black">.
(RuntimeDyldMachO.cpp:214)<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:10.5pt;font-family:"Calibri","sans-serif";color:black">Maybe this mask should be different?<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:10.5pt;font-family:"Calibri","sans-serif";color:black">Anyway, it seems like this relocation isn't implemented. (RuntimeDyldMachO.cpp:104)<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:10.5pt;font-family:"Calibri","sans-serif";color:black"><o:p> </o:p></span></p>
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<p class="MsoNormal"><b><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:black">From:
</span></b><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:black">Jiong Wang <<a href="mailto:jiwang@tilera.com">jiwang@tilera.com</a>><br>
<b>Date: </b>Tue, 9 Apr 2013 09:42:03 -0400<br>
<b>To: </b>Eran Weiss <<a href="mailto:eran.weiss@emc.com">eran.weiss@emc.com</a>><br>
<b>Cc: </b>"<a href="mailto:llvmdev@cs.uiuc.edu">llvmdev@cs.uiuc.edu</a>" <<a href="mailto:llvmdev@cs.uiuc.edu">llvmdev@cs.uiuc.edu</a>><br>
<b>Subject: </b>Re: [LLVMdev] Migration from JIT to MCJIT<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:10.5pt;font-family:"Calibri","sans-serif";color:black"><o:p> </o:p></span></p>
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<p class="MsoNormal"><span style="font-size:10.5pt;font-family:"MS Gothic";color:black">于</span><span style="font-size:10.5pt;font-family:"Calibri","sans-serif";color:black"> 2013/4/9 21:08, Weiss, Eran
</span><span style="font-size:10.5pt;font-family:"MS Gothic";color:black">写道</span><span style="font-size:10.5pt;font-family:"Calibri","sans-serif";color:black">:<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:10.5pt;font-family:"Calibri","sans-serif";color:black">Hi,<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:10.5pt;font-family:"Calibri","sans-serif";color:black"><o:p> </o:p></span></p>
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<p class="MsoNormal"><span style="font-size:10.5pt;font-family:"Calibri","sans-serif";color:black">I'm migrating my code (running on mac) from using JIT to MCJIT. My code generates in memory, mostly using the llvm-c api, and then runs the generated code.<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:10.5pt;font-family:"Calibri","sans-serif";color:black">When I try to use MCJIT I encounter a problem with relocations of external symbols – functions compiled statically beforehand with gcc.<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:10.5pt;font-family:"Calibri","sans-serif";color:black"><o:p> </o:p></span></p>
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<p class="MsoNormal"><span style="font-size:10.5pt;font-family:"Calibri","sans-serif";color:black">I get the following error:<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:10.5pt;font-family:"Calibri","sans-serif";color:black"><o:p> </o:p></span></p>
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<p class="MsoNormal"><span style="font-size:10.5pt;font-family:"Calibri","sans-serif";color:black">Invalid relocation type!<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:10.5pt;font-family:"Calibri","sans-serif";color:black">UNREACHABLE executed at /Users/weisse4/dev/llvm/llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldMachO.cpp:89<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:10.5pt;font-family:"Calibri","sans-serif";color:black"><o:p> </o:p></span></p>
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<p class="MsoNormal"><span style="font-size:10.5pt;font-family:"Calibri","sans-serif";color:black">While debugging, I see that the relocation type read in is 218103811, which seems corrupt to me.<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:10.5pt;font-family:"Calibri","sans-serif";color:black"><br>
Hi Weiss,<br>
<br>
I do not have any experience on Mach binary format, but the hex value of 218103811 is 0xd000003 (maybe the relocation type is RIT_Generic_PreboundLazyPointer = 3), something looks like a relocation entry composed of "symbol index" + "relocation type".<br>
maybe something is wrong, that the relocation entry is not anded with a mask to get the final relocation type.<br>
<br>
---<br>
Regards,<br>
Jiong<br>
<br>
<br>
<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:10.5pt;font-family:"Calibri","sans-serif";color:black">Did someone encounter a similar error? Or can direct me to changes that I need to do while migrating from JIT to MCJIT?<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:10.5pt;font-family:"Calibri","sans-serif";color:black"><o:p> </o:p></span></p>
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<p class="MsoNormal"><span style="font-size:10.5pt;font-family:"Calibri","sans-serif";color:black">Thanks.<o:p></o:p></span></p>
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<br>
<br>
<o:p></o:p></span></p>
<pre><span style="color:black">_______________________________________________<o:p></o:p></span></pre>
<pre><span style="color:black">LLVM Developers mailing list<o:p></o:p></span></pre>
<pre><span style="color:black"><a href="mailto:LLVMdev@cs.uiuc.edu">LLVMdev@cs.uiuc.edu</a> <a href="http://llvm.cs.uiuc.edu">http://llvm.cs.uiuc.edu</a><a href="http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev">http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev</a><o:p></o:p></span></pre>
<p class="MsoNormal"><span style="font-size:10.5pt;font-family:"Calibri","sans-serif";color:black"><o:p> </o:p></span></p>
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