[Bug tree-optimization/50873] New: The fix to PR50730 causes gcc.c-torture/unsorted/dilayout.c to ICE

[Bug tree-optimization/50873] New: The fix to PR50730 causes gcc.c-torture/unsorted/dilayout.c to ICE

[mgretton at sourceware dot org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50873

             Bug #: 50873
           Summary: The fix to PR50730 causes
                    gcc.c-torture/unsorted/dilayout.c to ICE
    Classification: Unclassified
           Product: gcc
           Version: 4.7.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: tree-optimization
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: mgretton@sourceware.org
                CC: irar@il.ibm.com
            Target: arm*-*-*


The fix to PR50730 (revision 180367 -
http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=180367) causes the test
gcc.c-torture/unsorted/dilayout.c to ICE at -O3.

A reduced test case is:

$ cat test.c
/* arm-none-eabi-gcc -mcpu=cortex-a9 -mfpu=neon -mfloat-abi=soft -O3 test.c  */
struct ii
{
  int a;
  int b;
};
struct foo
{
  int a;
  struct ii ab;
};
struct ii
foo (int *p, struct foo a)
{
  p[0] = a.a;
  p[1] = a.ab.a;
}
/* end of test.c.  */
$ arm-none-eabi-gcc -mcpu=cortex-a9 -mfpu=neon -mfloat-abi=soft -O3 test.c
test.c: In function 'foo':
test.c:15:11: internal compiler error: in expand_insn, at optabs.c:7693

-fno-tree-vectorize causes the issue to go away.

The issue still exists in revision 180524

[Bug tree-optimization/50873] The fix to PR50730 causes gcc.c-torture/unsorted/dilayout.c to ICE

[irar at il dot ibm.com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50873

Ira Rosen <irar at il dot ibm.com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2011-10-27
     Ever Confirmed|0                           |1

--- Comment #1 from Ira Rosen <irar at il dot ibm.com> 2011-10-27 08:44:32 UTC ---
I see this too, but I don't think it's my patch's fault. I reverted it and the
reduced test still failed. The patch makes no difference for this basic block -
it gets vectorized with or without it.

[Bug tree-optimization/50873] The fix to PR50730 causes gcc.c-torture/unsorted/dilayout.c to ICE

[mgretton at sourceware dot org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50873

--- Comment #2 from Matthew Gretton-Dann <mgretton at sourceware dot org> 2011-10-27 13:31:27 UTC ---
(In reply to comment #1)
> I see this too, but I don't think it's my patch's fault. I reverted it and the
> reduced test still failed. The patch makes no difference for this basic block -
> it gets vectorized with or without it.

Apologies if I've miss labelled this issue - git bisect suggested that r180367
was where the issue was introduced.  I will take another look this afternoon to
see if I misread the output and it was another check-in nearby.

[Bug tree-optimization/50873] The fix to PR50730 causes gcc.c-torture/unsorted/dilayout.c to ICE

[rsandifo at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50873

rsandifo@gcc.gnu.org <rsandifo at gcc dot gnu.org> changed:

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

--- Comment #3 from rsandifo at gcc dot gnu.org <rsandifo at gcc dot gnu.org> 2011-12-07 11:45:40 UTC ---
We need to tweak maybe_legitimize_operand_same_code
(thanks Ramana for the heads-up).  Testing a fix.

[Bug tree-optimization/50873] The fix to PR50730 causes gcc.c-torture/unsorted/dilayout.c to ICE

[rsandifo at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50873

--- Comment #4 from rsandifo at gcc dot gnu.org <rsandifo at gcc dot gnu.org> 2011-12-12 15:18:29 UTC ---
Author: rsandifo
Date: Mon Dec 12 15:18:24 2011
New Revision: 182244

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=182244
Log:
gcc/
    PR middle-end/50873
    * optabs.c (maybe_legitimize_operand_same_code): Use copy_to_mode_reg
    instead of force_reg.  Do nothing if the address is already a
    non-virtual pseudo register.

Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/optabs.c

[Bug tree-optimization/50873] The fix to PR50730 causes gcc.c-torture/unsorted/dilayout.c to ICE

[rsandifo at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50873

rsandifo@gcc.gnu.org <rsandifo at gcc dot gnu.org> changed:

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

--- Comment #5 from rsandifo at gcc dot gnu.org <rsandifo at gcc dot gnu.org> 2012-01-18 09:32:44 UTC ---
Fixed on trunk.