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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/78528] Recursion not optimized for structs
Date: Thu, 03 Jun 2021 04:52:44 +0000	[thread overview]
Message-ID: <bug-78528-4-YzWUcWlLri@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-78528-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78528

--- Comment #5 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
tailr1:
  D.2500 = strlen (_2);

  <bb 5> :
  lhs$m_value_10 = D.2500.m_value;
  _14 = lhs$m_value_10 + 1;
  D.2496.m_value = _14;

  <bb 6> :
  return D.2496;

For tailr on structures we only allow for structure copies and nothing else.
For an example, if we remove the + 1 part, we do get the tail recursion.  Now
the question becomes is it worth the effect in doing it.

clang can handle this case because they handle structures at a lower level than
GCC does.

           reply	other threads:[~2021-06-03  4:52 UTC|newest]

Thread overview: expand[flat|nested]  mbox.gz  Atom feed
 [parent not found: <bug-78528-4@http.gcc.gnu.org/bugzilla/>]

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