[Bug tree-optimization/56350] New: ICE in vectorizable_reduction, at tree-vect-loop.c:4731

[Bug tree-optimization/56350] New: ICE in vectorizable_reduction, at tree-vect-loop.c:4731

[antoine.balestrat at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56350

             Bug #: 56350
           Summary: ICE in vectorizable_reduction, at
                    tree-vect-loop.c:4731
    Classification: Unclassified
           Product: gcc
           Version: 4.8.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: tree-optimization
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: antoine.balestrat@gmail.com


Using GCC 4.8.0 as of 20130215 :

$ cat vect.c
int a, b, c;

void f(void)
{
    for(; c; c++)
        for(b = 0; b < 2; b++)
            a /= 8;
}

$ xgcc -O1 -ftree-vectorize -w vect.c
vect.c: In function ‘f’:
vect.c:3:6: internal compiler error: in vectorizable_reduction, at
tree-vect-loop.c:4731
 void f(void)
      ^
0xa8e953 vectorizable_reduction(gimple_statement_d*, gimple_stmt_iterator*,
gimple_statement_d**, _slp_tree*)
    ../../srcdir/gcc/tree-vect-loop.c:4727
0xa81ff0 vect_analyze_stmt(gimple_statement_d*, bool*, _slp_tree*)
    ../../srcdir/gcc/tree-vect-stmts.c:5691
0xa80f75 vect_analyze_stmt(gimple_statement_d*, bool*, _slp_tree*)
    ../../srcdir/gcc/tree-vect-stmts.c:5613
0x4cffb9 vect_analyze_loop_operations
    ../../srcdir/gcc/tree-vect-loop.c:1443
0xa8c064 vect_analyze_loop_2
    ../../srcdir/gcc/tree-vect-loop.c:1720
0xa8c064 vect_analyze_loop(loop*)
    ../../srcdir/gcc/tree-vect-loop.c:1773
0xa9e06c vectorize_loops()
    ../../srcdir/gcc/tree-vectorizer.c:113
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/56350] [4.7/4.8 Regression] ICE in vectorizable_reduction, at tree-vect-loop.c:4731

[mpolacek at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56350

Marek Polacek <mpolacek at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2013-02-15
                 CC|                            |mpolacek at gcc dot gnu.org
      Known to work|                            |4.6.4
   Target Milestone|---                         |4.8.0
            Summary|ICE in                      |[4.7/4.8 Regression] ICE in
                   |vectorizable_reduction, at  |vectorizable_reduction, at
                   |tree-vect-loop.c:4731       |tree-vect-loop.c:4731
     Ever Confirmed|0                           |1
      Known to fail|                            |4.7.3, 4.8.0

--- Comment #1 from Marek Polacek <mpolacek at gcc dot gnu.org> 2013-02-15 19:52:07 UTC ---
Confirmed.  ICEs with trunk/4.7.

[Bug tree-optimization/56350] [4.7/4.8 Regression] ICE in vectorizable_reduction, at tree-vect-loop.c:4731

[jakub at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56350

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |jakub at gcc dot gnu.org

--- Comment #2 from Jakub Jelinek <jakub at gcc dot gnu.org> 2013-02-17 13:31:58 UTC ---
Started with http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=182388

[Bug tree-optimization/56350] [4.7/4.8 Regression] ICE in vectorizable_reduction, at tree-vect-loop.c:4731

[jakub at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56350

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 #3 from Jakub Jelinek <jakub at gcc dot gnu.org> 2013-02-18 10:41:16 UTC ---
Created attachment 29481
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=29481
gcc48-pr56350.patch

Untested fix.

[Bug tree-optimization/56350] [4.7/4.8 Regression] ICE in vectorizable_reduction, at tree-vect-loop.c:4731

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56350

--- Comment #4 from Richard Biener <rguenth at gcc dot gnu.org> 2013-02-18 13:03:24 UTC ---
Author: rguenth
Date: Mon Feb 18 13:03:15 2013
New Revision: 196118

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=196118
Log:
2013-02-18  Richard Biener  <rguenther@suse.de>

    PR middle-end/56350
    * cfghooks.c (merge_blocks): If we merge a latch into another
    block adjust references to it.
    * cfgloop.c (flow_loops_find): Reset latch before recomputing it.
    (verify_loop_structure): Verify that a recorded latch is in fact
    a latch.

    * gcc.dg/torture/pr56350.c: New testcase.

Added:
    trunk/gcc/testsuite/gcc.dg/torture/pr56350.c
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/cfghooks.c
    trunk/gcc/cfgloop.c
    trunk/gcc/testsuite/ChangeLog

[Bug tree-optimization/56350] [4.7/4.8 Regression] ICE in vectorizable_reduction, at tree-vect-loop.c:4731

[jakub at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56350

--- Comment #5 from Jakub Jelinek <jakub at gcc dot gnu.org> 2013-02-18 14:19:04 UTC ---
The previous commit was for PR56349.

[Bug tree-optimization/56350] [4.7/4.8 Regression] ICE in vectorizable_reduction, at tree-vect-loop.c:4731

[jakub at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56350

--- Comment #6 from Jakub Jelinek <jakub at gcc dot gnu.org> 2013-02-19 09:14:41 UTC ---
Author: jakub
Date: Tue Feb 19 09:14:33 2013
New Revision: 196134

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=196134
Log:
    PR tree-optimization/56350
    * tree-vect-loop.c (vectorizable_reduction): If orig_stmt, return false
    if haven't found reduction or nested cycle operand, rather than
    asserting we must find it.

    * gcc.dg/pr56350.c: New test.

Added:
    trunk/gcc/testsuite/gcc.dg/pr56350.c
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/testsuite/ChangeLog
    trunk/gcc/tree-vect-loop.c

[Bug tree-optimization/56350] [4.7 Regression] ICE in vectorizable_reduction, at tree-vect-loop.c:4731

[jakub at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56350

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
      Known to work|                            |4.8.0
            Summary|[4.7/4.8 Regression] ICE in |[4.7 Regression] ICE in
                   |vectorizable_reduction, at  |vectorizable_reduction, at
                   |tree-vect-loop.c:4731       |tree-vect-loop.c:4731
      Known to fail|4.8.0                       |

--- Comment #7 from Jakub Jelinek <jakub at gcc dot gnu.org> 2013-02-19 09:19:34 UTC ---
Fixed on the trunk so far.

[Bug tree-optimization/56350] [4.7 Regression] ICE in vectorizable_reduction, at tree-vect-loop.c:4731

[jakub at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56350

--- Comment #8 from Jakub Jelinek <jakub at gcc dot gnu.org> 2013-02-19 17:30:35 UTC ---
Author: jakub
Date: Tue Feb 19 17:30:27 2013
New Revision: 196150

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=196150
Log:
    Backported from mainline
    2013-02-19  Jakub Jelinek  <jakub@redhat.com>

    PR tree-optimization/56350
    * tree-vect-loop.c (vectorizable_reduction): If orig_stmt, return false
    if haven't found reduction or nested cycle operand, rather than
    asserting we must find it.

    * gcc.dg/pr56350.c: New test.

Added:
    branches/gcc-4_7-branch/gcc/testsuite/gcc.dg/pr56350.c
Modified:
    branches/gcc-4_7-branch/gcc/ChangeLog
    branches/gcc-4_7-branch/gcc/testsuite/ChangeLog
    branches/gcc-4_7-branch/gcc/tree-vect-loop.c

[Bug tree-optimization/56350] [4.7 Regression] ICE in vectorizable_reduction, at tree-vect-loop.c:4731

[jakub at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56350

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

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

--- Comment #9 from Jakub Jelinek <jakub at gcc dot gnu.org> 2013-02-19 17:45:32 UTC ---
Fixed.