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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/110060] Adding optimizer hints to std::vector causes a new -Wstringop-overread false positive
Date: Wed, 31 May 2023 22:53:42 +0000 [thread overview]
Message-ID: <bug-110060-4-H8pLm5ywN4@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-110060-4@http.gcc.gnu.org/bugzilla/>
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110060
Andrew Pinski <pinskia at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Keywords| |missed-optimization
--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Hmm:
```
MEM[(struct _Vector_base *)&w]._M_impl.D.25239._M_start = _73;
_66 = _73 + 1;
MEM[(struct _Vector_base *)&w]._M_impl.D.25239._M_end_of_storage = _66;
MEM[(struct vector *)&w].D.25935._M_impl.D.25239._M_finish = _66;
_486 = _63 + 2;
v.D.25935._M_impl.D.25239._M_finish = _486;
_154 = _63 + 3;
v.D.25935._M_impl.D.25239._M_finish = _154;
_138 = MEM[(struct X * const &)&v];
_215 = v.D.25935._M_impl.D.25239._M_end_of_storage;
_216 = v.D.25935._M_impl.D.25239._M_finish;
if (_215 != _216)
```
There is huge missed optimizations here.
I noticed that the last fre is not iterative and we have the case where many of
the ifs are removed due to fre and forwprop at the end.
next prev parent reply other threads:[~2023-05-31 22:53 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-05-31 11:59 [Bug tree-optimization/110060] New: " redi at gcc dot gnu.org
2023-05-31 22:53 ` pinskia at gcc dot gnu.org [this message]
2023-05-31 23:07 ` [Bug tree-optimization/110060] " redi at gcc dot gnu.org
2023-05-31 23:16 ` pinskia at gcc dot gnu.org
2023-05-31 23:31 ` pinskia at gcc dot gnu.org
2023-05-31 23:32 ` redi at gcc dot gnu.org
2023-05-31 23:38 ` pinskia at gcc dot gnu.org
2023-06-01 8:37 ` redi at gcc dot gnu.org
2023-06-01 9:35 ` [Bug libstdc++/110060] [14 Regression] " redi at gcc dot gnu.org
2023-06-01 15:09 ` cvs-commit at gcc dot gnu.org
2023-06-01 15:11 ` redi at gcc dot gnu.org
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