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From: "jakub at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug tree-optimization/46957] http://blog.regehr.org/archives/320 Example 1
Date: Thu, 16 Dec 2010 09:31:00 -0000	[thread overview]
Message-ID: <bug-46957-4-68BXiKfQM7@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-46957-4@http.gcc.gnu.org/bugzilla/>

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46957

--- Comment #2 from Jakub Jelinek <jakub at gcc dot gnu.org> 2010-12-16 09:31:43 UTC ---
Indeed, that's another possibility, could handle even more complex expressions.
On the other side, it makes sense to do it only if the initial value is
constant and thus we can expect the result is constant too, otherwise we might
risk creating too expensive operation instead of the loop (especially when the
loop doesn't roll too many times).  And we'd need some peel limit for that too,
as for a couple of passes until optimizers clean stuff up we could increase
number of stmts a lot.


  parent reply	other threads:[~2010-12-16  9:31 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2010-12-15 14:47 [Bug tree-optimization/46957] New: " jakub at gcc dot gnu.org
2010-12-16  0:54 ` [Bug tree-optimization/46957] " hubicka at gcc dot gnu.org
2010-12-16  9:31 ` jakub at gcc dot gnu.org [this message]
2010-12-16 12:11 ` hubicka at gcc dot gnu.org
2021-08-10 17:47 ` pinskia at gcc dot gnu.org

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