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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/80641] missed optimization with with
 std::vector resize in loop
Date: Wed, 09 Aug 2023 23:15:25 +0000
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X-Bugzilla-Component: tree-optimization
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X-Bugzilla-Keywords: missed-optimization
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D80641

--- Comment #16 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Note starting in GCC 13 at -O3, we are able to optimize this all the way to:
```
int f ()
{
  int * _54;

  <bb 2> [local count: 114863531]:
  _54 =3D operator new (16);
  MEM <uint128_t> [(char * {ref-all})_54] =3D 0x30000000200000001;
  operator delete (_54, 16);
  return 0;

}
```
If we change the name of the function to f rather than main. In GCC 14 we a=
ble
to optimize even without the name change (there has been some inlining heur=
stic
changes there).=