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From: "msebor at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug tree-optimization/85315] missed range optimisation opportunity for derefences where index must be 0 or otherwise constrained
Date: Wed, 18 Nov 2020 15:46:04 +0000	[thread overview]
Message-ID: <bug-85315-4-8MfCi0xaf6@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-85315-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85315

--- Comment #14 from Martin Sebor <msebor at gcc dot gnu.org> ---
Andrew, we discussed the same idea for built-in functions at Couldron.  For
instance, in:

  void f (const char *s, int n)
  {
    char a[8];
    memcpy (a, s, n);     // n must be in [0, 8]
    if (n < 0 || n > 8)   // fold to false
      abort ();
  }

  parent reply	other threads:[~2020-11-18 15:46 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <bug-85315-4@http.gcc.gnu.org/bugzilla/>
2020-11-17 17:42 ` amacleod at redhat dot com
2020-11-18  7:37 ` rguenth at gcc dot gnu.org
2020-11-18 14:55 ` amacleod at redhat dot com
2020-11-18 15:17 ` jakub at gcc dot gnu.org
2020-11-18 15:46 ` msebor at gcc dot gnu.org [this message]
2020-11-18 19:05 ` rguenther at suse dot de
2020-11-19 16:24 ` amacleod at redhat dot com

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