[Bug c/46107] New: verify_loop_structure problem

[Bug c/46107] New: verify_loop_structure problem

[dcb314 at hotmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46107

           Summary: verify_loop_structure problem
           Product: gcc
           Version: 4.6.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: dcb314@hotmail.com


Created attachment 22100
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=22100
C source code

I just tried to compile package gambas2-2.21.0 with the latest 4.6
snapshot 20101016 on a Fedora Linux box. The compiler said

gbx_subr_math.c: In function 'SUBR_add_quick':
gbx_subr_math.c:295:6: error: edge from 7 to 9 should be marked irreducible
gbx_subr_math.c:295:6: internal compiler error: in verify_loop_structure, at
cfgloop.c:1562
Please submit a full bug report,
with preprocessed source if appropriate.
See <http://gcc.gnu.org/bugs.html> for instructions.

Source code attached. Flag -O3 required.

[Bug c/46107] [4.6 Regression] -ftree-loop-distribute-patterns caused verify_loop_structure problem

[hjl.tools at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46107

H.J. Lu <hjl.tools at gmail dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2010.10.20 23:05:14
                 CC|                            |hjl.tools at gmail dot com
            Summary|verify_loop_structure       |[4.6 Regression]
                   |problem                     |-ftree-loop-distribute-patt
                   |                            |erns caused
                   |                            |verify_loop_structure
                   |                            |problem
     Ever Confirmed|0                           |1

[Bug tree-optimization/46107] [4.6 Regression] -ftree-loop-distribute-patterns caused verify_loop_structure problem

[pinskia at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46107

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|---                         |4.6.0

[Bug tree-optimization/46107] [4.6 Regression] -ftree-loop-distribute-patterns caused verify_loop_structure problem

[jakub at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46107

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

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

--- Comment #1 from Jakub Jelinek <jakub at gcc dot gnu.org> 2010-11-02 16:18:16 UTC ---
Reduced testcase:

int foo (void) __attribute__ ((noreturn));

void
bar (int x, int *y, int z)
{
  static void *j[] = { &&l1, &&l2 };
l1:
  if (*y)
    goto *j[z];
  foo ();
l2:
  *y ^= (x & 1) ? -1 : 0;
  goto *j[x];
}

[Bug tree-optimization/46107] [4.6 Regression] -ftree-loop-distribute-patterns caused verify_loop_structure problem

[jakub at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46107

--- Comment #2 from Jakub Jelinek <jakub at gcc dot gnu.org> 2010-11-02 16:32:24 UTC ---
verify_loop_structure () passes before loop unswitching, but doesn't pass after
it.

[Bug tree-optimization/46107] [4.6 Regression] -ftree-loop-distribute-patterns caused verify_loop_structure problem

[jakub at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46107

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> 2010-11-02 19:14:43 UTC ---
Created attachment 22234
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=22234
gcc46-pr46107.patch

Untested fix.

[Bug tree-optimization/46107] [4.6 Regression] -ftree-loop-distribute-patterns caused verify_loop_structure problem

[jakub at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46107

--- Comment #4 from Jakub Jelinek <jakub at gcc dot gnu.org> 2010-11-03 09:49:21 UTC ---
Author: jakub
Date: Wed Nov  3 09:49:16 2010
New Revision: 166234

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=166234
Log:
    PR tree-optimization/46107
    * cfgloopmanip.c (loop_version): Set irred_flag back into entry->flags
    if cfg_hook_duplicate_loop_to_header_edge failed.

    * gcc.c-torture/compile/pr46107.c: New test.

Added:
    trunk/gcc/testsuite/gcc.c-torture/compile/pr46107.c
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/cfgloopmanip.c
    trunk/gcc/testsuite/ChangeLog

[Bug tree-optimization/46107] [4.6 Regression] -ftree-loop-distribute-patterns caused verify_loop_structure problem

[jakub at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46107

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

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

--- Comment #5 from Jakub Jelinek <jakub at gcc dot gnu.org> 2010-11-03 09:50:00 UTC ---
Fixed.

[Bug tree-optimization/46107] [4.6 Regression] -ftree-loop-distribute-patterns caused verify_loop_structure problem

[jakub at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46107

--- Comment #6 from Jakub Jelinek <jakub at gcc dot gnu.org> 2010-11-11 20:33:21 UTC ---
Author: jakub
Date: Thu Nov 11 20:33:18 2010
New Revision: 166615

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=166615
Log:
    Backport from mainline
    2010-11-03  Jakub Jelinek  <jakub@redhat.com>

    PR tree-optimization/46107
    * cfgloopmanip.c (loop_version): Set irred_flag back into entry->flags
    if cfg_hook_duplicate_loop_to_header_edge failed.

    * gcc.c-torture/compile/pr46107.c: New test.

Added:
    branches/gcc-4_5-branch/gcc/testsuite/gcc.c-torture/compile/pr46107.c
Modified:
    branches/gcc-4_5-branch/gcc/ChangeLog
    branches/gcc-4_5-branch/gcc/cfgloopmanip.c
    branches/gcc-4_5-branch/gcc/testsuite/ChangeLog

[Bug tree-optimization/46107] [4.6 Regression] -ftree-loop-distribute-patterns caused verify_loop_structure problem

[jakub at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46107

--- Comment #7 from Jakub Jelinek <jakub at gcc dot gnu.org> 2010-11-12 11:28:35 UTC ---
Author: jakub
Date: Fri Nov 12 11:28:32 2010
New Revision: 166649

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=166649
Log:
    Backport from mainline
    2010-11-03  Jakub Jelinek  <jakub@redhat.com>

    PR tree-optimization/46107
    * cfgloopmanip.c (loop_version): Set irred_flag back into entry->flags
    if cfg_hook_duplicate_loop_to_header_edge failed.

    * gcc.c-torture/compile/pr46107.c: New test.

Added:
    branches/gcc-4_4-branch/gcc/testsuite/gcc.c-torture/compile/pr46107.c
Modified:
    branches/gcc-4_4-branch/gcc/ChangeLog
    branches/gcc-4_4-branch/gcc/cfgloopmanip.c
    branches/gcc-4_4-branch/gcc/gimplify.c
    branches/gcc-4_4-branch/gcc/testsuite/ChangeLog