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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/94802] Failure to recognize identities with __builtin_clz
Date: Tue, 05 Jan 2021 10:28:36 +0000	[thread overview]
Message-ID: <bug-94802-4-PhZIbEmwc6@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-94802-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94802

--- Comment #7 from Richard Biener <rguenth at gcc dot gnu.org> ---
Which means it won't help for foo():

  <bb 2> :
  if (b_2(D) >= a_3(D))
    goto <bb 3>; [INV]
  else
    goto <bb 4>; [INV]

  <bb 3> :
  iftmp.0_5 = b_2(D) - a_3(D);

  <bb 4> :
  # iftmp.0_1 = PHI <iftmp.0_5(3), 0(2)>
  return iftmp.0_1;

  parent reply	other threads:[~2021-01-05 10:28 UTC|newest]

Thread overview: 14+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-04-27 15:10 [Bug tree-optimization/94802] New: " gabravier at gmail dot com
2020-04-27 15:14 ` [Bug tree-optimization/94802] " gabravier at gmail dot com
2020-04-27 15:22 ` jakub at gcc dot gnu.org
2020-12-31 10:10 ` cvs-commit at gcc dot gnu.org
2020-12-31 10:15 ` jakub at gcc dot gnu.org
2021-01-02  8:44 ` jakub at gcc dot gnu.org
2021-01-05 10:25 ` rguenth at gcc dot gnu.org
2021-01-05 10:28 ` rguenth at gcc dot gnu.org [this message]
2021-01-05 11:18 ` jakub at gcc dot gnu.org
2021-01-05 12:13 ` jakub at gcc dot gnu.org
2021-01-05 14:32 ` denis.campredon at gmail dot com
2021-01-05 18:14 ` cvs-commit at gcc dot gnu.org
2021-01-05 18:16 ` jakub at gcc dot gnu.org
2021-08-14 22:29 ` pinskia at gcc dot gnu.org

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