[Bug c/56984] New: GCC-4.8.0 ICE in tree_vrp.c

[Bug c/56984] New: GCC-4.8.0 ICE in tree_vrp.c

[ishiura-compiler at ml dot kwansei.ac.jp]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56984

             Bug #: 56984
           Summary: GCC-4.8.0 ICE in tree_vrp.c
    Classification: Unclassified
           Product: gcc
           Version: 4.8.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: ishiura-compiler@ml.kwansei.ac.jp


GCC 4.8.0 with "-O1 -ftree-vrp" option ICEs on 
the following code where sizeof(int) == 4.
The failure occurs in Linux (x86_64 and i686)
and Mac OS X (x86_64).

  $ cat error.c

  int g = 0;
  int main(void)
    {
    if ( (g>>31) < -1 ) { g++; }
    return 0;
  }

  $ x86_64-unknown-linux-gnu-gcc-4.8.0 error.c -O1 -ftree-vrp
  error.c: In function 'main':
  error.c:3:5: internal compiler error: in remove_range_assertions, at
  tree-vrp.c:6276
   int main(void)
       ^
  0x936e7e remove_range_assertions
  ../../gcc/tree-vrp.c:6276
  0x936e7e execute_vrp
  ../../gcc/tree-vrp.c:9299
  Please submit a full bug report,
  with preprocessed source if appropriate.
  Please include the complete backtrace with any bug report.
  See <http://gcc.gnu.org/bugs.html> for instructions.

[Bug tree-optimization/56984] [4.8/4.9 Regression] ICE in tree_vrp.c

[jakub at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56984

Jakub Jelinek <jakub at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2013-04-17
                 CC|                            |jakub at gcc dot gnu.org
   Target Milestone|---                         |4.8.1
            Summary|GCC-4.8.0 ICE in tree_vrp.c |[4.8/4.9 Regression] ICE in
                   |                            |tree_vrp.c
     Ever Confirmed|0                           |1

--- Comment #1 from Jakub Jelinek <jakub at gcc dot gnu.org> 2013-04-17 06:23:02 UTC ---
Started with http://gcc.gnu.org/r184927

[Bug tree-optimization/56984] [4.8/4.9 Regression] ICE in tree_vrp.c

[jakub at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56984

Jakub Jelinek <jakub at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |ASSIGNED
         AssignedTo|unassigned at gcc dot       |jakub at gcc dot gnu.org
                   |gnu.org                     |

--- Comment #2 from Jakub Jelinek <jakub at gcc dot gnu.org> 2013-04-17 07:30:20 UTC ---
Created attachment 29887
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=29887
gcc49-pr56984.patch

Untested fix.  Another thing is that fold resp. gimple_fold aren't able to
optimize (x >> N) < M into 0 if M << N is the minimum value, but that isn't
something VRP should handle.

[Bug tree-optimization/56984] [4.8/4.9 Regression] ICE in tree_vrp.c

[jakub at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56984

Jakub Jelinek <jakub at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|ASSIGNED                    |RESOLVED
         Resolution|                            |FIXED

--- Comment #3 from Jakub Jelinek <jakub at gcc dot gnu.org> 2013-04-18 08:02:24 UTC ---
Author: jakub
Date: Thu Apr 18 07:54:58 2013
New Revision: 198051

URL: http://gcc.gnu.org/viewcvs?rev=198051&root=gcc&view=rev
Log:
    PR tree-optimization/56984
    * tree-vrp.c (register_edge_assert_for_2): For (x >> M) < N
    and (x >> M) >= N don't register any assertion if N << M is the
    minimum value.

    * gcc.c-torture/compile/pr56984.c: New test.

Added:
    trunk/gcc/testsuite/gcc.c-torture/compile/pr56984.c
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/testsuite/ChangeLog
    trunk/gcc/tree-vrp.c

Author: jakub
Date: Thu Apr 18 07:56:03 2013
New Revision: 198052

URL: http://gcc.gnu.org/viewcvs?rev=198052&root=gcc&view=rev
Log:
    PR tree-optimization/56984
    * tree-vrp.c (register_edge_assert_for_2): For (x >> M) < N
    and (x >> M) >= N don't register any assertion if N << M is the
    minimum value.

    * gcc.c-torture/compile/pr56984.c: New test.

Added:
    branches/gcc-4_8-branch/gcc/testsuite/gcc.c-torture/compile/pr56984.c
Modified:
    branches/gcc-4_8-branch/gcc/ChangeLog
    branches/gcc-4_8-branch/gcc/testsuite/ChangeLog
    branches/gcc-4_8-branch/gcc/tree-vrp.c