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From: "spop at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug tree-optimization/47271] [4.6 Regression] if-conversion removes a test (if), the function generates invalid outputs
Date: Tue, 18 Jan 2011 19:39:00 -0000	[thread overview]
Message-ID: <bug-47271-4-7ArROQ9Mev@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-47271-4@http.gcc.gnu.org/bugzilla/>

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47271

--- Comment #5 from Sebastian Pop <spop at gcc dot gnu.org> 2011-01-18 18:45:27 UTC ---
In this loop:

  for (i=0, nops=0 ; i<codelen ; i += ((codestr[i] >= 90) ? 3 : 1))
    {
      addrmap[i] = i - nops;
      if (codestr[i] == 9)
    nops++;
    }

it looks like this part: i += ((codestr[i] >= 90) ? 3 : 1)
is miscompiled into:

  # i_35 = PHI <i_19(8), 0(2)>
  iftmp.0_4 = [cond_expr] D.2702_12 != 9 ? 3 : 1;
  i_19 = iftmp.0_4 + i_35;

the predicate for the increment is wrongly computed.


  parent reply	other threads:[~2011-01-18 18:45 UTC|newest]

Thread overview: 20+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-01-12 19:04 [Bug c/47271] New: gcc-4.6 -O1 -ftree-vectorize " victor.stinner at haypocalc dot com
2011-01-12 19:42 ` [Bug c/47271] " victor.stinner at haypocalc dot com
2011-01-12 20:00 ` [Bug tree-optimization/47271] " hjl.tools at gmail dot com
2011-01-12 20:59 ` hjl.tools at gmail dot com
2011-01-12 21:35 ` [Bug tree-optimization/47271] [4.6 Regression] if-conversion " rguenth at gcc dot gnu.org
2011-01-12 23:48 ` spop at gcc dot gnu.org
2011-01-18 19:39 ` spop at gcc dot gnu.org [this message]
2011-01-18 21:33 ` spop at gcc dot gnu.org
2011-01-24 18:17 ` jakub at gcc dot gnu.org
2011-01-24 18:53 ` spop at gcc dot gnu.org
2011-01-24 19:25 ` spop at gcc dot gnu.org
2011-01-24 19:54 ` spop at gcc dot gnu.org
2011-01-24 19:57 ` jakub at gcc dot gnu.org
2011-01-24 20:21 ` spop at gcc dot gnu.org
2011-01-24 20:51 ` jakub at gcc dot gnu.org
2011-01-24 21:07 ` spop at gcc dot gnu.org
2011-01-24 21:09 ` jakub at gcc dot gnu.org
2011-01-25 15:04 ` spop at gcc dot gnu.org
2011-01-25 15:05 ` spop at gcc dot gnu.org
2011-02-02 17:49 ` dnovillo at gcc dot gnu.org

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