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From: "rguenth at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug rtl-optimization/106041] [12/13 Regression] infinite loop in
 fast_dce at -O1 with aarch64
Date: Tue, 21 Feb 2023 14:52:14 +0000
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X-Bugzilla-Component: rtl-optimization
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X-Bugzilla-Keywords: compile-time-hog, needs-bisection, needs-reduction
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D106041

--- Comment #10 from Richard Biener <rguenth at gcc dot gnu.org> ---
Confirmed, it never finishes word-level iteration.

static void
fast_dce (bool word_level)

{
...
  while (global_changed)
    {
...
    }

IMHO that "fast" DCE should hard-limit the iteration count anyway.  I'm try=
ing
to reduce the testcase based on that.=