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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/111388] std:.get_if variant, unnecessary branch when outside of if statement Date: Tue, 12 Sep 2023 14:55:57 +0000 [thread overview] Message-ID: <bug-111388-4-HAPfYZ1GHR@http.gcc.gnu.org/bugzilla/> (raw) In-Reply-To: <bug-111388-4@http.gcc.gnu.org/bugzilla/> https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111388 --- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> --- Note variant can still hold neither ... You might need to add a check for valueless_by_exception here. But variant::index could be improved to say the only values that are valid is [0,N],[-1]. and that will remove the check. Note clang even produces the similar code even with libc++: xorl %eax, %eax cmpl $2, 8(%rdi) cmovaeq %rax, %rdi Just GCC isolates the null pointer access.
next prev parent reply other threads:[~2023-09-12 14:55 UTC|newest] Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top 2023-09-12 11:13 [Bug c++/111388] New: " federico at kircheis dot it 2023-09-12 14:55 ` pinskia at gcc dot gnu.org [this message] 2023-09-12 14:58 ` [Bug tree-optimization/111388] " pinskia at gcc dot gnu.org
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