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From: "jakub at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug tree-optimization/94956] Unable to remove impossible ffs() test
 for zero
Date: Tue, 05 May 2020 18:21:35 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D94956

--- Comment #3 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Another option would be to fold FFS (x) for x known non-zero into CTZ (x) +=
 1
in match.pd.=