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From: "rguenth at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
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Subject: [Bug tree-optimization/102880] [12 Regression] Dead Code Elimination
 Regression at -O3
Date: Fri, 22 Oct 2021 08:44:18 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D102880

--- Comment #4 from Richard Biener <rguenth at gcc dot gnu.org> ---
Created attachment 51652
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=3D51652&action=3Dedit
not working patch

OK, that's definitely a too simplistic idea, the basic assessment still hol=
ds
though.  CD-DCE benefits from forwarders for equal PHI arguments.

Not working patch attached (using the common dominator idea).  Regresses
for example gcc.c-torture/execute/20050218-1.c.=