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<p class="MsoNormal"><span lang="EN-US">Hi Florian,</span></p>
<p class="MsoNormal"><span lang="EN-US"> It</span>’<span lang="EN-US">s been a while since I lasted posted a reply on this mailing list. I</span>’<span lang="EN-US">ve been going through code in the FuzzMutate folder and commit
<a href="https://reviews.llvm.org/D96654">https://reviews.llvm.org/D96654</a> for quite some time now. While the current IRMutator implementation allows for module / function level mutation, only instruction level mutations are implemented, namely instruction
injection and deletion, which does not preserve the original semantics of the program. I think the sound mutation rule examples provided by Johannes is something I work on in the summer. Aside from that, do you see any opportunity that D96654 alive2-based
fuzzer could be expanded on, or are there anything that you wished to implement but not yet done (because I see the label NOT-TO-BE-MERGED)?</span></p>
<p class="MsoNormal"><span lang="EN-US">My personal opinion is that it</span>’<span lang="EN-US">s pretty feature complete. Any other advice will be helpful too:)</span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Thanks in advance,</span></p>
<p class="MsoNormal"><span lang="EN-US">Chibin Zhang</span></p>
<p class="MsoNormal"><span lang="EN-US">2021.3.25</span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:12.0pt;font-family:SimSun"><o:p> </o:p></span></p>
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<p class="MsoNormal" style="border:none;padding:0cm"><b>发件人<span lang="EN-US">: </span>
</b><span lang="EN-US"><a href="mailto:florian_hahn@apple.com">Florian Hahn</a><br>
</span><b>发送时间<span lang="EN-US">: </span></b><span lang="EN-US">2021</span>年<span lang="EN-US">3</span>月<span lang="EN-US">10</span>日<span lang="EN-US"> 5:22<br>
</span><b>收件人<span lang="EN-US">: </span></b><span lang="EN-US"><a href="mailto:johannesdoerfert@gmail.com">Johannes Doerfert</a>;
<a href="mailto:zhangchb1@shanghaitech.edu.cn"><span lang="EN-US"><span lang="EN-US">张驰斌</span></span></a><br>
</span><b>抄送<span lang="EN-US">: </span></b><span lang="EN-US"><a href="mailto:llvm-dev@lists.llvm.org">llvm-dev</a>;
<a href="mailto:regehr@cs.utah.edu">John Regehr</a><br>
</span><b>主题<span lang="EN-US">: </span></b><span lang="EN-US">Re: [llvm-dev] Applying for GSoC 2021(Fuzzing LLVM-IR Passes)</span></p>
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<p class="MsoNormal"><span lang="EN-US" style="font-size:12.0pt;font-family:SimSun"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">> On Mar 8, 2021, at 23:17, Johannes Doerfert <johannesdoerfert@gmail.com> wrote:</span></p>
<p class="MsoNormal"><span lang="EN-US">> </span></p>
<p class="MsoNormal"><span lang="EN-US">> Having Alive2 as oracle would certainly be great.</span></p>
<p class="MsoNormal"><span lang="EN-US">> </span></p>
<p class="MsoNormal"><span lang="EN-US">> Some rough ideas that can be worked on in parallel if we have multiple GSoC students:</span></p>
<p class="MsoNormal"><span lang="EN-US">> - mutation rules we know are sound, e.g., remove guarantees, add 1 iteration loops, etc.</span></p>
<p class="MsoNormal"><span lang="EN-US">> - input generation, equivalence checking (alive, partial evaluation, ...)</span></p>
<p class="MsoNormal"><span lang="EN-US">> - fragment extraction from larger codes + input tracking -> reproducer splitting, faster equivalence checking, ...</span></p>
<p class="MsoNormal"><span lang="EN-US">> </span></p>
<p class="MsoNormal"><span lang="EN-US">> We certainly can come up with more things.</span></p>
<p class="MsoNormal"><span lang="EN-US">> </span></p>
<p class="MsoNormal"><span lang="EN-US">> Would either or both of your (or anyone else) be interested in co-mentoring students?</span></p>
<p class="MsoNormal"><span lang="EN-US">> We have multiple interested ones already, even though my project description is lacking any detail.</span></p>
<p class="MsoNormal"><span lang="EN-US">> </span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">I</span>’<span lang="EN-US">d be happy to help out.</span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Cheers,</span></p>
<p class="MsoNormal"><span lang="EN-US">Florian</span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
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