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<p class="MsoNormal">Hi Alexey,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Adding llvm-ir bitcode support means adding/adapting the tags for LOAD/STORE instructions and adding<o:p></o:p></p>
<p class="MsoNormal">the support for the noalias_sidechannel at the right places.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I had a short attempt to implement it when preparing the public patches, but I am not familiar with that<o:p></o:p></p>
<p class="MsoNormal">part of the llvm code. When I noticed that it would take a lot longer than anticipated, I postponed it.<o:p></o:p></p>
<p class="MsoNormal">Also because it is likely that the way how the noalias_sidechannel was added to LoadInst/StoreInst might<o:p></o:p></p>
<p class="MsoNormal">change.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">At this moment, I am not planning to work on this. For the current implementation, there might be<o:p></o:p></p>
<p class="MsoNormal">a number of possibilities for adding support :<o:p></o:p></p>
<p class="MsoNormal"> - maybe 2 new tags are needed (FUNC_CODE_INST_{LOAD_NOALIAS,STORE_NOALIAS})<o:p></o:p></p>
<p class="MsoNormal"> - or maybe it is sufficient to add the noalias_sidechannels as extra operands and look at the number of<o:p></o:p></p>
<p class="MsoNormal"> operands to see if they are present or not<o:p></o:p></p>
<p class="MsoNormal"> - or maybe it is sufficient to look at the number of operands, and the noalias_sidechannel operand should<o:p></o:p></p>
<p class="MsoNormal"> be added with an extra bit, indicating if it is really there or not...<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Greetings,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Jeroen Dobbelaere<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal"><b>From:</b> Alexey Zhikhartsev <alexey.zhikhar@gmail.com> <br>
<b>Sent:</b> Thursday, October 31, 2019 16:21<br>
<b>To:</b> Jeroen Dobbelaere <dobbel@synopsys.com><br>
<b>Cc:</b> llvm-dev@lists.llvm.org<br>
<b>Subject:</b> Re: [llvm-dev] Full restrict support - status update<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Hi Jeroen,<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Thank you very much for the great work, it is much appreciated.<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">> - For now, there is still no llvm-ir bitcode support for the load/store noalias_sidechannel argument<span style="font-size:9.5pt;font-family:"Arial",sans-serif">.</span><o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Do you have plans to work on this in the near future? Do you know how much work it is and if there are significant hurdles?<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,<o:p></o:p></p>
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<p class="MsoNormal">Alexey<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">[...]<o:p></o:p></p>
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