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From: "pinskia at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c++/112335] missed optimization on reset and assign unique_ptr
Date: Wed, 01 Nov 2023 15:51:32 +0000	[thread overview]
Message-ID: <bug-112335-4-BKxckogZHL@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-112335-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=112335

--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
  __old_p_6 = MEM[(struct s * &)ps1_2(D)];
  MEM[(struct s * &)ps1_2(D)] = 0B;
  if (__old_p_6 != 0B)
    goto <bb 3>; [53.47%]
  else
    goto <bb 4>; [46.53%]

  <bb 3> [local count: 574129752]:
  s::~s (__old_p_6);
  operator delete (__old_p_6, 1);

  <bb 4> [local count: 1073741824]:
  __p_4 = MEM[(struct s * &)ps2_3(D)];
  MEM[(struct s * &)ps2_3(D)] = 0B;
  __old_p_5 = MEM[(struct s * &)ps1_2(D)];

Well s::~s could touch the reference std::unique_ptr<s> (ps1).

So this could in theory be an invalid optimization.

I am not sure if that is the only issue here though.

  reply	other threads:[~2023-11-01 15:51 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-11-01 13:26 [Bug c++/112335] New: " federico at kircheis dot it
2023-11-01 15:51 ` pinskia at gcc dot gnu.org [this message]
2023-11-02  7:17 ` [Bug c++/112335] " federico at kircheis dot it
2023-11-02  7:19 ` federico at kircheis dot it
2023-11-02  7:30 ` pinskia at gcc dot gnu.org
2023-11-02  8:01 ` federico at kircheis dot it
2023-11-02 17:23 ` redi at gcc dot gnu.org
2023-11-03  8:06 ` federico at kircheis dot it
2023-11-03  9:10 ` redi at gcc dot gnu.org
2023-11-03 10:23 ` federico at kircheis dot it
2023-11-03 14:23 ` redi at gcc dot gnu.org

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