<div dir="ltr">Davide, you should s/~0/EmptyKey/<div>and s/~1/TombstoneKey/</div></div><div class="gmail_extra"><br><div class="gmail_quote">On Tue, Dec 13, 2016 at 7:33 PM, Vedant Kumar via Phabricator <span dir="ltr"><<a href="mailto:reviews@reviews.llvm.org" target="_blank">reviews@reviews.llvm.org</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">vsk added inline comments.<br>
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Comment at: include/llvm/Transforms/<wbr>Scalar/GVNExpression.h:63<br>
<span class="">+      return false;<br>
+    if (getOpcode() == ~0U || getOpcode() == ~1U)<br>
+      return true;<br>
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</span>Could you add a brief comment explaining the significance of the ~0U, ~1U, and ~2U opcodes before using them? In particular, it would be nice to explain why we don't look at 'Other' when Opcode is in {~0,~1}.<br>
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<a href="https://reviews.llvm.org/D26224" rel="noreferrer" target="_blank">https://reviews.llvm.org/<wbr>D26224</a><br>
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