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From: "rguenth at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug tree-optimization/111820] [13/14 Regression] Compiler time hog
 in the vectorizer with `-O3 -fno-tree-vrp`
Date: Mon, 16 Oct 2023 07:14:18 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D111820

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Priority|P3                          |P2
                 CC|                            |crazylht at gmail dot com

--- Comment #3 from Richard Biener <rguenth at gcc dot gnu.org> ---
        for (unsigned i =3D 0; i !=3D skipn - 1; i++)
          begin =3D wi::mul (begin, wi::to_wide (step_expr));

(gdb) p skipn
$5 =3D 4294967292

niters is 4294967292 in vect_update_ivs_after_vectorizer.  Maybe the loop
should terminate when begin is zero.  But I wonder why we pass in 'niters'
and then name it 'skip_niters' ...

CCing author for fixing.=