<div dir="ltr">Thanks! Constant expressions strike again...working on a reduction now.<br></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Sun, Jun 20, 2021 at 5:49 AM Florian Hahn <<a href="mailto:florian_hahn@apple.com">florian_hahn@apple.com</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div style="overflow-wrap: break-word;"><br><div><br><blockquote type="cite"><div>On Jun 14, 2021, at 17:55, Sanjay Patel via llvm-commits <<a href="mailto:llvm-commits@lists.llvm.org" target="_blank">llvm-commits@lists.llvm.org</a>> wrote:</div><br><div><div><br>Author: Sanjay Patel<br>Date: 2021-06-14T12:54:35-04:00<br>New Revision: 8591640379ac9175a8a8493126ecf0b44e3bb4af<br><br>URL: <a href="https://github.com/llvm/llvm-project/commit/8591640379ac9175a8a8493126ecf0b44e3bb4af" target="_blank">https://github.com/llvm/llvm-project/commit/8591640379ac9175a8a8493126ecf0b44e3bb4af</a><br>DIFF: <a href="https://github.com/llvm/llvm-project/commit/8591640379ac9175a8a8493126ecf0b44e3bb4af.diff" target="_blank">https://github.com/llvm/llvm-project/commit/8591640379ac9175a8a8493126ecf0b44e3bb4af.diff</a><br><br>LOG: [InstCombine] add DeMorgan folds for logical ops in select form<br><br>We canonicalized to these select patterns (poison-safe logic)<br>with D101191, so we need to reduce 'not' ops when possible<br>as we would with 'and'/'or' instructions.<br><br>This is shown in a secondary example in:<br><a href="https://llvm.org/PR50389" target="_blank">https://llvm.org/PR50389</a><br><br><a href="https://alive2.llvm.org/ce/z/BvsESh" target="_blank">https://alive2.llvm.org/ce/z/BvsESh</a><br><br></div></div></blockquote><br></div><div>It looks like this is causing an infinite loop in InstCombine: <font face="arial, sans-serif"><span style="white-space:pre-wrap"><a href="https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=35399" target="_blank">https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=35399</a></span></font></div><div><br></div><div>Cheers,</div><div>Florian</div><br></div></blockquote></div>