[Bug tree-optimization/24483] New: [4.1 Regression] ICE in ivopts

[Bug tree-optimization/24483] New: [4.1 Regression] ICE in ivopts

[pinskia at gcc dot gnu dot org]

Take the following code:
int f ()
{       int j0, j1, j2, j3, j4, j5, j6, j7, j8, j9, a;
        a = 0;
        for (j0 = 0; j0 < 2; j0 ++)
        for (j1 = j0; j1 < 2; j1 ++)
        for (j2 = j1; j2 < 2; j2 ++)
        for (j3 = j2; j3 < 2; j3 ++)
        for (j4 = j3; j4 < 2; j4 ++)
        for (j5 = j4; j5 < 2; j5 ++)
        for (j6 = j5; j6 < 2; j6 ++)
        for (j7 = j6; j7 < 2; j7 ++)
        for (j8 = j7; j8 < 2; j8 ++)
        for (j9 = j8; j9 < 2; j9 ++)
        a += j0 + j1 + j2 + j3 + j4 + j5 + j6 + j7 + j8 + j9;
        return a;
}

---

Right now we ICE:
t.c:2: internal compiler error: in aff_combination_to_tree, at
tree-ssa-loop-ivopts.c:2948
Please submit a full bug report,
with preprocessed source if appropriate.
See <URL:http://gcc.gnu.org/bugs.html> for instructions.

This was generated with the awk script from PR 18595.


-- 
           Summary: [4.1 Regression] ICE in ivopts
           Product: gcc
           Version: 4.1.0
            Status: UNCONFIRMED
          Keywords: ice-on-valid-code
          Severity: critical
          Priority: P2
         Component: tree-optimization
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: pinskia at gcc dot gnu dot org
GCC target triplet: x86_64-linux-gnu
OtherBugsDependingO 18595
             nThis:


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=24483

[Bug tree-optimization/24483] [4.1 Regression] ICE in ivopts

[pinskia at gcc dot gnu dot org]

-- 

pinskia at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |rakdver at gcc dot gnu dot
                   |                            |org
   Target Milestone|---                         |4.1.0


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=24483

[Bug tree-optimization/24483] [4.1 Regression] ICE in ivopts

[steven at gcc dot gnu dot org]

------- Comment #1 from steven at gcc dot gnu dot org  2005-10-25 15:30 -------
Backtrace:

Breakpoint 1, fancy_abort (file=0xb1cc18
"../../mainline/gcc/tree-ssa-loop-ivopts.c",
    line=2948, function=0xb1d0bb "aff_combination_to_tree") at diagnostic.c:590
590       internal_error ("in %s, at %s:%d", function, trim_filename (file),
line);
(gdb) up
#1  0x000000000056db37 in aff_combination_to_tree (comb=0x7fbfffec30)
    at tree-ssa-loop-ivopts.c:2948
2948      gcc_assert (comb->n == MAX_AFF_ELTS || comb->rest == NULL_TREE);
(gdb) p *comb
$17 = {type = 0x2a9589e580, mask = 4294967295, offset = 0, n = 2, elts =
{0x2a95a8f680,
    0x2a95a639a0, 0x2a95a6d8c0, 0x2a95a6d850, 0x2a95a6d850, 0x2a95a6d8c0,
0x2a95a6d930,
    0x2a95a6d9a0}, coefs = {1, 1, 0, 0, 1, 1, 1, 1}, rest = 0x2a95a8f700}
(gdb) call debug_generic_expr (comb->elts[0])
(unsigned intD.3) -j9D.1618_41
(gdb) call debug_generic_expr (comb->elts[1])
ivtmp.30D.1722_4
(gdb) call debug_generic_expr (comb->elts[2])
j6D.1615_65
(gdb) call debug_generic_expr (comb->elts[3])
j5D.1614_64
(gdb) call debug_generic_expr (comb->elts[4])
j5D.1614_64
(gdb) call debug_generic_expr (comb->elts[5])
j6D.1615_65
(gdb) call debug_generic_expr (comb->elts[6])
j7D.1616_66
(gdb) call debug_generic_expr (comb->elts[7])
j8D.1617_67
(gdb) call debug_generic_expr (comb->rest)
(unsigned intD.3) j9D.1618_41
(gdb) 

Why do we have (comb->n == 2) when we have 8 elts?


-- 

steven at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
     Ever Confirmed|0                           |1
   Last reconfirmed|0000-00-00 00:00:00         |2005-10-25 15:30:24
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=24483

[Bug tree-optimization/24483] [4.1 Regression] ICE in ivopts

[rakdver at atrey dot karlin dot mff dot cuni dot cz]

------- Comment #2 from rakdver at atrey dot karlin dot mff dot cuni dot cz  2005-10-25 15:56 -------
Subject: Re:  [4.1 Regression] ICE in ivopts

Hello,

> Breakpoint 1, fancy_abort (file=0xb1cc18
> "../../mainline/gcc/tree-ssa-loop-ivopts.c",
>     line=2948, function=0xb1d0bb "aff_combination_to_tree") at diagnostic.c:590
> 590       internal_error ("in %s, at %s:%d", function, trim_filename (file),
> line);
> (gdb) up
> #1  0x000000000056db37 in aff_combination_to_tree (comb=0x7fbfffec30)
>     at tree-ssa-loop-ivopts.c:2948
> 2948      gcc_assert (comb->n == MAX_AFF_ELTS || comb->rest == NULL_TREE);
> (gdb) p *comb
> $17 = {type = 0x2a9589e580, mask = 4294967295, offset = 0, n = 2, elts =
> {0x2a95a8f680,
>     0x2a95a639a0, 0x2a95a6d8c0, 0x2a95a6d850, 0x2a95a6d850, 0x2a95a6d8c0,
> 0x2a95a6d930,
>     0x2a95a6d9a0}, coefs = {1, 1, 0, 0, 1, 1, 1, 1}, rest = 0x2a95a8f700}
> (gdb) call debug_generic_expr (comb->elts[0])
> (unsigned intD.3) -j9D.1618_41
> (gdb) call debug_generic_expr (comb->elts[1])
> ivtmp.30D.1722_4
> (gdb) call debug_generic_expr (comb->elts[2])
> j6D.1615_65
> (gdb) call debug_generic_expr (comb->elts[3])
> j5D.1614_64
> (gdb) call debug_generic_expr (comb->elts[4])
> j5D.1614_64
> (gdb) call debug_generic_expr (comb->elts[5])
> j6D.1615_65
> (gdb) call debug_generic_expr (comb->elts[6])
> j7D.1616_66
> (gdb) call debug_generic_expr (comb->elts[7])
> j8D.1617_67
> (gdb) call debug_generic_expr (comb->rest)
> (unsigned intD.3) j9D.1618_41
> (gdb) 
> 
> Why do we have (comb->n == 2) when we have 8 elts?

that's not necessarily a bug, # of elements in the combination may get
changed due to arithmetical operations with it, and the old elements
are not zeroed.  But once comb->n < MAX_AFF_ELTS, comb->rest should be
moved to the available slot in elts, which apparently some function
fails to do.  I will have a look.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=24483

[Bug tree-optimization/24483] [4.1 Regression] ICE in ivopts

[rakdver at gcc dot gnu dot org]

------- Comment #3 from rakdver at gcc dot gnu dot org  2005-10-26 13:02 -------
Patch:

http://gcc.gnu.org/ml/gcc-patches/2005-10/msg01527.html


-- 

rakdver at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |patch


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=24483

[Bug tree-optimization/24483] [4.1 Regression] ICE in ivopts

[mmitchel at gcc dot gnu dot org]

------- Comment #4 from mmitchel at gcc dot gnu dot org  2005-10-31 06:35 -------
ICE on reasonable code; showstopper.


-- 

mmitchel at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Priority|P2                          |P1


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=24483

[Bug tree-optimization/24483] [4.1 Regression] ICE in ivopts

[rakdver at gcc dot gnu dot org]

------- Comment #5 from rakdver at gcc dot gnu dot org  2005-11-03 16:28 -------
Subject: Bug 24483

Author: rakdver
Date: Thu Nov  3 16:28:09 2005
New Revision: 106440

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=106440
Log:
        PR tree-optimization/24483
        * tree-ssa-loop-ivopts.c (aff_combination_add_elt): Move rest
        field to elts if possible.


Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/tree-ssa-loop-ivopts.c


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=24483

[Bug tree-optimization/24483] [4.1 Regression] ICE in ivopts

[pinskia at gcc dot gnu dot org]

------- Comment #6 from pinskia at gcc dot gnu dot org  2005-11-03 18:12 -------
Fixed.


-- 

pinskia at gcc dot gnu dot org changed:

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


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=24483