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From: "jakub at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug rtl-optimization/51023] [4.7 Regression] likely integer wrong code bug
Date: Wed, 09 Nov 2011 09:42:00 -0000	[thread overview]
Message-ID: <bug-51023-4-TM9ZXmPF4L@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-51023-4@http.gcc.gnu.org/bugzilla/>

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51023

--- Comment #4 from Jakub Jelinek <jakub at gcc dot gnu.org> 2011-11-09 09:39:28 UTC ---
Created attachment 25765
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=25765
gcc47-pr51023.patch

Part of that patch is clearly bogus, as const_op here is a constant in wider
mode than the inner mode of SIGN_EXTEND, thus before the comparison checked
not just that the sign bit is clear, but also any bits above it.

The simplify_set change from the same patch is questionable too.


  parent reply	other threads:[~2011-11-09  9:39 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-11-08  5:54 [Bug c/51023] New: " regehr at cs dot utah.edu
2011-11-08  6:47 ` [Bug c/51023] " regehr at cs dot utah.edu
2011-11-08 10:26 ` [Bug rtl-optimization/51023] [4.7 Regression] " rguenth at gcc dot gnu.org
2011-11-08 23:15 ` jakub at gcc dot gnu.org
2011-11-09  9:42 ` jakub at gcc dot gnu.org [this message]
2011-11-10 16:02 ` jakub at gcc dot gnu.org
2011-11-10 17:29 ` jakub at gcc dot gnu.org

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