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From: "hubicka at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug libstdc++/110287] _M_check_len is expensive
Date: Fri, 16 Jun 2023 14:48:10 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D110287

--- Comment #1 from Jan Hubicka <hubicka at gcc dot gnu.org> ---
Another problem is:

  D.27747 =3D _8;
  if (__n.3_2 > _8)
    goto <bb 5>; [34.00%]
  else
    goto <bb 6>; [66.00%]

  <bb 5> [local count: 364926196]:

  <bb 6> [local count: 1073312330]:
  # _18 =3D PHI <&D.27747(4), &__n(5)>
  _3 =3D *_18;

which is simply computation of maximum but done in a way not understood unt=
il
phiprop=