[Bug tree-optimization/57081] New: Segmentation fault in simple_iv (tree-scalar-evolution.c:3151)

[Bug tree-optimization/57081] New: Segmentation fault in simple_iv (tree-scalar-evolution.c:3151)

[antoine.balestrat at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57081

             Bug #: 57081
           Summary: Segmentation fault in simple_iv
                    (tree-scalar-evolution.c:3151)
    Classification: Unclassified
           Product: gcc
           Version: 4.9.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: tree-optimization
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: antoine.balestrat@gmail.com


Using GCC 4.9.0 as of 20130426 :

$ cat seg.c
int a;

void f(void)
{
    int b;

    if(0)
lbl:
        goto lbl;

    if(b)
    {
        int p = 0;
        goto lbl;
    }

    a = 0;
    while(b++);
    goto lbl;
}

$ xgcc -w -O2 seg.c
seg.c: In function ‘f’:
seg.c:20:1: internal compiler error: Segmentation fault
 }
 ^
0x90ba1f crash_signal
    ../../srcdir/gcc/toplev.c:333
0x9a90c4 simple_iv(loop*, loop*, tree_node*, affine_iv*, bool)
    ../../srcdir/gcc/tree-scalar-evolution.c:3151
0x86ec0f is_comparison_with_loop_invariant_p
    ../../srcdir/gcc/predict.c:1084
0x8725ac predict_loops
    ../../srcdir/gcc/predict.c:1552
0x8725ac tree_estimate_probability()
    ../../srcdir/gcc/predict.c:2342
0x872f10 tree_estimate_probability_driver
    ../../srcdir/gcc/predict.c:2379
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.
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From: "mikpe at it dot uu.se" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c/57080] Invalid optimization (-O2) when doing double -> int conversion (on big endian archs(?))
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http://gcc.gnu.org/bugzilla/show_bug.cgi?idW080

--- Comment #3 from Mikael Pettersson <mikpe at it dot uu.se> 2013-04-26 11:49:44 UTC ---
Created attachment 29946
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id)946
test case

I can reproduce the issue on m68k: with the attached test case I get 4 on
m68k-linux (big-endian), but 5 on x86_64-linux (little-endian).

I don't see any conversions to char or unsigned, so I don't think PR27394 is
related.

The issue goes away with -ffloat-store on m68k.  I haven't analyzed it further.

On the big-endian armv5teb-linux-gnueabi I get 5, but it's soft-fp.

[Bug tree-optimization/57081] [4.9 Regression] Segmentation fault in simple_iv (tree-scalar-evolution.c:3151)

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57081

--- Comment #2 from Richard Biener <rguenth at gcc dot gnu.org> 2013-04-26 12:00:08 UTC ---
Happens via max_loop_iterations called from finite_loop_p called from DCE.
It expects loop_optimizer_finalize to free them - which is probably a
good assumption.  I'll fix it.

[Bug tree-optimization/57081] [4.9 Regression] Segmentation fault in simple_iv (tree-scalar-evolution.c:3151)

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57081

Richard Biener <rguenth at gcc dot gnu.org> changed:

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

--- Comment #3 from Richard Biener <rguenth at gcc dot gnu.org> 2013-04-29 09:09:28 UTC ---
Author: rguenth
Date: Mon Apr 29 09:09:08 2013
New Revision: 198392

URL: http://gcc.gnu.org/viewcvs?rev=198392&root=gcc&view=rev
Log:
2013-04-29  Richard Biener  <rguenther@suse.de>

    PR tree-optimization/57081
    * loop-init.c: Include tree-flow.h.
    (loop_optimizer_finalize): Free number of iteration estimates.
    * Makefile.in (loop-init.o): Add $(TREE_FLOW_H) dependency.

    * gcc.dg/torture/pr57081.c: New testcase.

Added:
    trunk/gcc/testsuite/gcc.dg/torture/pr57081.c
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/Makefile.in
    trunk/gcc/loop-init.c
    trunk/gcc/testsuite/ChangeLog