<div dir="ltr"><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Sun, Jun 20, 2021 at 12:24 PM 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;">Hi,<br><div><br><blockquote type="cite"><div>On Oct 25, 2020, at 17:47, Nikita Popov 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: Nikita Popov<br>Date: 2020-10-25T18:46:50+01:00<br>New Revision: 22a5cde541c3306e53279fd02c6d60ae6178ef10<br><br>URL: <a href="https://github.com/llvm/llvm-project/commit/22a5cde541c3306e53279fd02c6d60ae6178ef10" target="_blank">https://github.com/llvm/llvm-project/commit/22a5cde541c3306e53279fd02c6d60ae6178ef10</a><br>DIFF: <a href="https://github.com/llvm/llvm-project/commit/22a5cde541c3306e53279fd02c6d60ae6178ef10.diff" target="_blank">https://github.com/llvm/llvm-project/commit/22a5cde541c3306e53279fd02c6d60ae6178ef10.diff</a><br><br>LOG: [SCEV] Separate out constant folding in mul expr creation<br><br>Separate out the code handling constant folding into a separate<br>block, that is independent of other folds that need a constant<br>first operand. Also make some minor adjustments to make the<br>constant folding look nearly identical to the same code in<br>getAddExpr().<br><br>The only reason this change is not strictly NFC is that the<br>C1*(C2+V) fold is moved below the constant folding, which means<br>that it now also applies to C1*C2*(C3+V), as it should.<br><br>Added: <br></div></div></blockquote></div><br><div><br></div><div>It looks like this change may cause a crash in LoopStrengthReduce: <font face="arial, sans-serif"><span style="white-space:pre-wrap"><a href="https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=35400" target="_blank">https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=35400</a></span></font></div><div><br></div><div>To reproduce, run `llc` on <span style="font-family:arial,sans-serif;white-space:pre-wrap"> </span><font face="arial, sans-serif"><span style="white-space:pre-wrap"><a href="https://oss-fuzz.com/download?testcase_id=5243727227518976" target="_blank">https://oss-fuzz.com/download?testcase_id=5243727227518976</a></span></font></div></div></blockquote><div><br></div><div>Looks like this is <a href="https://bugs.llvm.org/show_bug.cgi?id=50765">https://bugs.llvm.org/show_bug.cgi?id=50765</a>.</div><div><br></div><div>Nikita<br> </div></div></div>