<div dir="ltr">Thanks! I reverted and will reduce the test. Most likely, there is an opposing transform in instcombine.<br></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Fri, Jun 10, 2022 at 3:05 AM Martin Storsjö <<a href="mailto:martin@martin.st">martin@martin.st</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">On Thu, 9 Jun 2022, Sanjay Patel via llvm-commits wrote:<br>
<br>
><br>
> Author: Sanjay Patel<br>
> Date: 2022-06-09T16:59:26-04:00<br>
> New Revision: afa192cfb6049a15c5542d132d500b910b802c74<br>
><br>
> URL: <a href="https://github.com/llvm/llvm-project/commit/afa192cfb6049a15c5542d132d500b910b802c74" rel="noreferrer" target="_blank">https://github.com/llvm/llvm-project/commit/afa192cfb6049a15c5542d132d500b910b802c74</a><br>
> DIFF: <a href="https://github.com/llvm/llvm-project/commit/afa192cfb6049a15c5542d132d500b910b802c74.diff" rel="noreferrer" target="_blank">https://github.com/llvm/llvm-project/commit/afa192cfb6049a15c5542d132d500b910b802c74.diff</a><br>
><br>
> LOG: [InstCombine] add narrowing transform for low-masked binop with zext operand<br>
><br>
> <a href="https://alive2.llvm.org/ce/z/hRy3rE" rel="noreferrer" target="_blank">https://alive2.llvm.org/ce/z/hRy3rE</a><br>
><br>
> As shown in D123408, we can produce this pattern when moving<br>
> cast around, and we already have a related fold for a binop<br>
> with a constant operand.<br>
<br>
This commit causes breakage for me - one file which used to compile in <br>
around a second now hangs (doesn't complete in many minutes at least).<br>
<br>
To reproduce, download <a href="https://martin.st/temp/remap-preproc.c" rel="noreferrer" target="_blank">https://martin.st/temp/remap-preproc.c</a> and try to <br>
compile it with "clang -target x86_64-w64-mingw32 -w -c -O2 <br>
remap-preproc.c".<br>
<br>
// Martin<br>
<br>
</blockquote></div>