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From: "pinskia at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug tree-optimization/102216] False positive warray-bounds with -O2
Date: Mon, 06 Sep 2021 20:46:14 +0000 [thread overview]
Message-ID: <bug-102216-4-rcgwazL1zv@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-102216-4@http.gcc.gnu.org/bugzilla/>
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102216
--- Comment #2 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
(In reply to Andrew Pinski from comment #1)
> The problem is dead code:
> language_names_p_9 = &MEM <const char *> [(void *)_4 + 24B];
> MEM[(const char * *)_4 + 24B] = "";
> MEM[(const char * *)_4 + 32B] = "";
> MEM[(const char * *)_4 + 40B] = 0B;
> _2 = _4 + 40;
> D.50907._M_comp = compare_cstrings;
> __comp = D.50907;
> if (_2 != language_names_p_9)
> goto <bb 3>; [53.47%]
> else
> goto <bb 12>; [46.53%]
>
> <bb 3> [local count: 574129759]:
> _15 = _2 - language_names_p_9;
> _16 = _15 /[ex] 8;
>
> ...
> _22 = _2 - language_names_p_9;
I have a (hack) patch which removes the first if statement but still does not
fold _15 and _22.
next prev parent reply other threads:[~2021-09-06 20:46 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-09-06 10:14 [Bug tree-optimization/102216] New: " vries at gcc dot gnu.org
2021-09-06 10:45 ` [Bug tree-optimization/102216] " pinskia at gcc dot gnu.org
2021-09-06 20:46 ` pinskia at gcc dot gnu.org [this message]
2021-09-07 1:32 ` [Bug tree-optimization/102216] [12 Regression] missed optimization causing Warray-bounds pinskia at gcc dot gnu.org
2021-09-07 1:47 ` pinskia at gcc dot gnu.org
2021-09-07 6:31 ` pinskia at gcc dot gnu.org
2021-09-07 7:21 ` pinskia at gcc dot gnu.org
2021-09-07 18:50 ` pinskia at gcc dot gnu.org
2021-09-07 21:37 ` pinskia at gcc dot gnu.org
2021-09-15 16:40 ` msebor at gcc dot gnu.org
2021-09-15 19:19 ` pinskia at gcc dot gnu.org
2021-10-27 9:28 ` pinskia at gcc dot gnu.org
2021-11-23 0:50 ` pinskia at gcc dot gnu.org
2021-11-23 1:31 ` pinskia at gcc dot gnu.org
2021-11-23 5:30 ` pinskia at gcc dot gnu.org
2021-11-23 8:45 ` pinskia at gcc dot gnu.org
2021-11-23 9:57 ` cvs-commit at gcc dot gnu.org
2021-11-23 10:01 ` pinskia at gcc dot gnu.org
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