[Bug tree-optimization/34330] New: [4.3 Regression] IC-ftree-parallelize-loops=4 ICE

[Bug tree-optimization/34330] New: [4.3 Regression] IC-ftree-parallelize-loops=4 ICE

[jakub at gcc dot gnu dot org]

/* { dg-do compile } */
/* { dg-options "-O3 -ftree-parallelize-loops=4" } */
struct T
{
  int t;
  struct { short s1, s2, s3, s4 } *s;
};

void
foo (int *a, int *b, int *c, int *d, struct T *e)
{
  int i;
  for (i = 0; i < e->t; i++)
    {
      e->s[i].s1 = a[i];
      e->s[i].s2 = b[i];
      e->s[i].s3 = c[i];
      e->s[i].s4 = d[i];
    }
}

ICEs on x86_64-linux with
test.c: In function 'foo':
test.c:11: internal compiler error: in get_smt_for, at tree-ssa-alias.c:3203
Please submit a full bug report,
with preprocessed source if appropriate.
See <http://gcc.gnu.org/bugs.html> for instructions.


-- 
           Summary: [4.3 Regression] IC-ftree-parallelize-loops=4 ICE
           Product: gcc
           Version: 4.3.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: tree-optimization
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: jakub at gcc dot gnu dot org
 GCC build triplet: i686-pc-linux-gnu
  GCC host triplet: i686-pc-linux-gnu
GCC target triplet: i686-*-*, x86_64-*-*
 BugsThisDependsOn: 33453


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34330

[Bug tree-optimization/34330] -ftree-parallelize-loops=4 ICE with the vectorizer also

[pinskia at gcc dot gnu dot org]

------- Comment #1 from pinskia at gcc dot gnu dot org  2007-12-10 00:23 -------
This is a vectorizer vs not being able to run may_alias after it.

Confirmed.

(gdb) p debug_generic_expr (tag_type)
vector short int


(gdb) p debug_tree(tag)
 <symbol_memory_tag 0x42791ea0 SMT.7
    type <record_type 0x4277ff50 type_0 DI
        size <integer_cst 0x426ce810 constant invariant 64>
        unit size <integer_cst 0x426ce840 constant invariant 8>
        align 16 symtab 0 alias set 5 canonical type 0x4277ff50
        fields <field_decl 0x426eda20 s1 type <integer_type 0x426f5230 short
int>
            HI file t.c line 6 col 18
            size <integer_cst 0x426ce540 constant invariant 16>
            unit size <integer_cst 0x426ce570 constant invariant 2>
            align 16 offset_align 128
            offset <integer_cst 0x426ce300 constant invariant 0>
            bit offset <integer_cst 0x426ceb40 constant invariant 0> context
<record_type 0x4277ff50> chain <field_decl 0x426eda80 s2>> context
<translation_unit_decl 0x4278f1c0 D.1555>
        pointer_to_this <pointer_type 0x4278f070> chain <type_decl 0x4278f000
D.1520>>
    addressable used file t.c line 11 col 1 context <function_decl 0x42781d80
foo>>
$3 = void
(gdb) p debug_generic_expr (0x4277ff50)
struct 
{
  short int s1;
  short int s2;
  short int s3;
  short int s4;
}

(gdb) p tag_set
$5 = 6
(gdb) p get_alias_set (tag) 
$6 = 5


-- 

pinskia at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |dorit at gcc dot gnu dot org
             Status|UNCONFIRMED                 |NEW
     Ever Confirmed|0                           |1
  GCC build triplet|i686-pc-linux-gnu           |
   GCC host triplet|i686-pc-linux-gnu           |
 GCC target triplet|i686-*-*, x86_64-*-*        |
           Keywords|                            |ice-on-valid-code
   Last reconfirmed|0000-00-00 00:00:00         |2007-12-10 00:23:44
               date|                            |
            Summary|-ftree-parallelize-loops=4  |-ftree-parallelize-loops=4
                   |ICE                         |ICE with the vectorizer also


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34330

[Bug tree-optimization/34330] -ftree-parallelize-loops=4 ICE with the vectorizer also

[rakdver at gcc dot gnu dot org]

-- 

rakdver at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
         AssignedTo|unassigned at gcc dot gnu   |rakdver at gcc dot gnu dot
                   |dot org                     |org
             Status|NEW                         |ASSIGNED
   Last reconfirmed|2007-12-10 00:23:44         |2007-12-16 22:07:18
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34330

[Bug tree-optimization/34330] -ftree-parallelize-loops=4 ICE with the vectorizer also

[rakdver at gcc dot gnu dot org]

------- Comment #2 from rakdver at gcc dot gnu dot org  2007-12-18 18:51 -------
I do not see a way how to fix this in 4.3, other than disabling vectorizer when
parallelization is enabled, or vice versa.


-- 

rakdver at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
         AssignedTo|rakdver at gcc dot gnu dot  |unassigned at gcc dot gnu
                   |org                         |dot org
             Status|ASSIGNED                    |NEW


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34330

[Bug tree-optimization/34330] -ftree-parallelize-loops=4 ICE with the vectorizer also

[dorit at gcc dot gnu dot org]

------- Comment #3 from dorit at gcc dot gnu dot org  2007-12-19 09:38 -------
> This is a vectorizer vs not being able to run may_alias after it

can you please remind me why we can't run may_alias after the vectorizer? (and
what do you think can be done about it?)


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34330

[Bug tree-optimization/34330] -ftree-parallelize-loops=4 ICE with the vectorizer also

[jakub at gcc dot gnu dot org]

------- Comment #4 from jakub at gcc dot gnu dot org  2007-12-19 09:46 -------
We could even TODO_rebuild_alias only if vectorizer changed anything...


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34330

[Bug tree-optimization/34330] -ftree-parallelize-loops=4 ICE with the vectorizer also

[rakdver at gcc dot gnu dot org]

------- Comment #5 from rakdver at gcc dot gnu dot org  2008-01-21 17:35 -------
(In reply to comment #3)
> > This is a vectorizer vs not being able to run may_alias after it
> 
> can you please remind me why we can't run may_alias after the vectorizer? (and
> what do you think can be done about it?)

As for this ICE: may_alias rebuilds the smt's, and finds that the smt for the
pointers created by vectorizer should be different (based on their type, not
the artificial ones created by vectorizer).

If we removed the hacks to update the alias info from vectorizer and run
may_alias instead, we might get type-based alias analysis related
misscompilations, as we create code of form

vector_type *p = &object_of_arbitrary_type;
*p = something;

And TBA might decide that references through vector_type and arbitrary_type
cannot alias.

I actually tried this some time ago, and I was not able to get misscompilations
this way (I am not really sure why).  However, I got many fails in the
testsuite (that I did not have time to investigate), so there may be some other
problems with alias analysis after vectorizer.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34330

[Bug tree-optimization/34330] -ftree-parallelize-loops=4 ICE with the vectorizer also

[razya at il dot ibm dot com]

------- Comment #6 from razya at il dot ibm dot com  2008-05-12 09:13 -------
(In reply to comment #0)
> /* { dg-do compile } */
> /* { dg-options "-O3 -ftree-parallelize-loops=4" } */
> struct T
> {
>   int t;
>   struct { short s1, s2, s3, s4 } *s;
> };
> void
> foo (int *a, int *b, int *c, int *d, struct T *e)
> {
>   int i;
>   for (i = 0; i < e->t; i++)
>     {
>       e->s[i].s1 = a[i];
>       e->s[i].s2 = b[i];
>       e->s[i].s3 = c[i];
>       e->s[i].s4 = d[i];
>     }
> }
> ICEs on x86_64-linux with
> test.c: In function 'foo':
> test.c:11: internal compiler error: in get_smt_for, at tree-ssa-alias.c:3203
> Please submit a full bug report,
> with preprocessed source if appropriate.
> See <http://gcc.gnu.org/bugs.html> for instructions.

I'm getting the same ICE (with r134722) when running spec2006/gobmk on power6.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34330

[Bug tree-optimization/34330] -ftree-parallelize-loops=4 ICE with the vectorizer also

[razya at il dot ibm dot com]

------- Comment #7 from razya at il dot ibm dot com  2008-05-12 09:42 -------
(In reply to comment #6)
> I'm getting the same ICE (with r134722) when running spec2006/gobmk on power6.

The same failure appears also for other benchmarks from spec2006:
h264ref, gromacs, calculix, tonto, wrf


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34330

[Bug tree-optimization/34330] -ftree-parallelize-loops=4 ICE with the vectorizer also

[rguenth at gcc dot gnu dot org]

------- Comment #8 from rguenth at gcc dot gnu dot org  2008-05-13 09:07 -------
To fix potential TBAA miscompilations the vectorizer could mark all pointer
(types) it creates with TYPE_REF_CAN_ALIAS_ALL.  But I guess I have a more
pragmatic fix for this.


-- 

rguenth at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
         AssignedTo|unassigned at gcc dot gnu   |rguenth at gcc dot gnu dot
                   |dot org                     |org
             Status|NEW                         |ASSIGNED
   Last reconfirmed|2007-12-16 22:07:18         |2008-05-13 09:07:52
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34330

[Bug tree-optimization/34330] -ftree-parallelize-loops=4 ICE with the vectorizer also

[rguenth at gcc dot gnu dot org]

------- Comment #9 from rguenth at gcc dot gnu dot org  2008-05-15 08:22 -------
Fixed on the trunk.


-- 

rguenth at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
      Known to fail|                            |4.3.0
      Known to work|                            |4.4.0
   Target Milestone|---                         |4.4.0


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34330

[Bug tree-optimization/34330] -ftree-parallelize-loops=4 ICE with the vectorizer also

[rguenth at gcc dot gnu dot org]

------- Comment #10 from rguenth at gcc dot gnu dot org  2008-05-15 08:22 -------
Subject: Bug 34330

Author: rguenth
Date: Thu May 15 08:21:32 2008
New Revision: 135329

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=135329
Log:
2008-05-15  Richard Guenther  <rguenther@suse.de>

        PR tree-optimization/34330
        * tree-ssa-alias.c (get_smt_for): Only assert that accesses
        through the pointer will alias the SMT.

        * gcc.dg/torture/pr34330.c: New testcase.

Added:
    trunk/gcc/testsuite/gcc.dg/torture/pr34330.c
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/testsuite/ChangeLog
    trunk/gcc/tree-ssa-alias.c


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34330

[Bug tree-optimization/34330] -ftree-parallelize-loops=4 ICE with the vectorizer also

[razya at il dot ibm dot com]

------- Comment #11 from razya at il dot ibm dot com  2008-05-15 09:23 -------
(In reply to comment #10)
> Subject: Bug 34330
> Author: rguenth
> Date: Thu May 15 08:21:32 2008
> New Revision: 135329
> URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=135329
> Log:
> 2008-05-15  Richard Guenther  <rguenther@suse.de>
>         PR tree-optimization/34330
>         * tree-ssa-alias.c (get_smt_for): Only assert that accesses
>         through the pointer will alias the SMT.
>         * gcc.dg/torture/pr34330.c: New testcase.
> Added:
>     trunk/gcc/testsuite/gcc.dg/torture/pr34330.c
> Modified:
>     trunk/gcc/ChangeLog
>     trunk/gcc/testsuite/ChangeLog
>     trunk/gcc/tree-ssa-alias.c

/* { dg-do compile } */
/* { dg-options "-O3 -ftree-parallelize-loops=4 -c" } */

struct p7prior_s {

  int   mnum;                   /* number of mat emission Dirichlet mixtures */
  float mq[200];          /* probabilities of mnum components          */
  float m[200][20];  /* match emission terms per mix component    */

};

struct p7prior_s *default_amino_prior(void);
struct p7prior_s *P7AllocPrior(void);

struct p7prior_s *
default_amino_prior(void)
{
  struct p7prior_s *pri;

  static float defmq[5] = {
    0.178091, 0.056591, 0.0960191, 0.0781233, 0.0834977 };
 static float defm[5][6] = {
    { 0.270671, 0.039848, 0.017576, 0.016415, 0.014268,
      0.216147 },
    { 0.021465, 0.010300, 0.011741, 0.010883, 0.385651,
      0.029156 },
    { 0.561459, 0.045448, 0.438366, 0.764167, 0.087364,
      0.583402 },
    { 0.070143, 0.011140, 0.019479, 0.094657, 0.013162,
      0.073732 },
    { 0.041103, 0.014794, 0.005610, 0.010216, 0.153602,
      0.012049 }
  };

  pri = P7AllocPrior();
  pri->mnum  = 5;
  for (q = 0; q < pri->mnum; q++)
    {
      pri->mq[q] = defmq[q];
      for (x = 0; x < 6; x++)
        pri->m[q][x] = defm[q][x];
    }
  return pri;
}

After applying Richard's patch, I'm still getting what seems to be a similar
problem.
prior.c:17: internal compiler error: in add_call_clobber_ops, at
tree-ssa-operands.c:1822
this was tested on power6, when both vectoriztion and autopar are enabled.
no failure when enabled seperately.



-- 

razya at il dot ibm dot com changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |razya at il dot ibm dot com


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34330

[Bug tree-optimization/34330] -ftree-parallelize-loops=4 ICE with the vectorizer also

[rguenth at gcc dot gnu dot org]

------- Comment #12 from rguenth at gcc dot gnu dot org  2008-05-15 09:27 -------
  int q, x;

is missing in the testcase.  I suppose you tried on the 4.3 branch?


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34330

[Bug tree-optimization/34330] -ftree-parallelize-loops=4 ICE with the vectorizer also

[rguenth at gcc dot gnu dot org]

------- Comment #13 from rguenth at gcc dot gnu dot org  2008-05-15 09:29 -------
I see this also even without the patch.  Can you open a new PR for this?


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34330

[Bug tree-optimization/34330] -ftree-parallelize-loops=4 ICE with the vectorizer also

[razya at il dot ibm dot com]

------- Comment #14 from razya at il dot ibm dot com  2008-05-15 09:41 -------
(In reply to comment #13)
> I see this also even without the patch.  Can you open a new PR for this?

(In reply to comment #12)
>   int q, x;
> is missing in the testcase.  I suppose you tried on the 4.3 branch?

No, actually it's 4.4


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34330

[Bug tree-optimization/34330] -ftree-parallelize-loops=4 ICE with the vectorizer also

[razya at il dot ibm dot com]

------- Comment #15 from razya at il dot ibm dot com  2008-05-15 09:46 -------
(In reply to comment #13)
> I see this also even without the patch.  Can you open a new PR for this?

Sure.
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36244


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34330

[Bug tree-optimization/34330] -ftree-parallelize-loops=4 ICE with the vectorizer also

[rguenth at gcc dot gnu dot org]

------- Comment #16 from rguenth at gcc dot gnu dot org  2008-05-20 21:04 -------
Fixed.


-- 

rguenth at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|ASSIGNED                    |RESOLVED
         Resolution|                            |FIXED
   Target Milestone|4.4.0                       |4.3.1


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34330

[Bug tree-optimization/34330] -ftree-parallelize-loops=4 ICE with the vectorizer also

[rguenth at gcc dot gnu dot org]

------- Comment #17 from rguenth at gcc dot gnu dot org  2008-05-20 21:05 -------
Subject: Bug 34330

Author: rguenth
Date: Tue May 20 21:03:59 2008
New Revision: 135680

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=135680
Log:
2008-05-20  Richard Guenther  <rguenther@suse.de>

        Backport from mainline:
        2008-05-15  Richard Guenther  <rguenther@suse.de>

        PR tree-optimization/34330
        * tree-ssa-alias.c (get_smt_for): Only assert that accesses
        through the pointer will alias the SMT.

        * gcc.dg/torture/pr34330.c: New testcase.

        PR middle-end/36244
        * tree-ssa-alias.c (new_type_alias): Do not set TREE_READONLY.
        * tree-flow-inline.h (unmodifiable_var_p): Memory tags never
        represent unmodifiable vars.

        * gcc.dg/torture/pr36244.c: New testcase.

Added:
    branches/gcc-4_3-branch/gcc/testsuite/gcc.dg/torture/pr34330.c
      - copied unchanged from r135329,
trunk/gcc/testsuite/gcc.dg/torture/pr34330.c
    branches/gcc-4_3-branch/gcc/testsuite/gcc.dg/torture/pr36244.c
      - copied unchanged from r135336,
trunk/gcc/testsuite/gcc.dg/torture/pr36244.c
Modified:
    branches/gcc-4_3-branch/gcc/ChangeLog
    branches/gcc-4_3-branch/gcc/testsuite/ChangeLog
    branches/gcc-4_3-branch/gcc/tree-flow-inline.h
    branches/gcc-4_3-branch/gcc/tree-ssa-alias.c


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34330