[Bug tree-optimization/44913] [4.6 Regression] -ftree-vectorize causes FAIL: gcc.dg/pr44838.c execution test

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=44913

Richard Guenther  changed:

   What|Removed |Added

 Status|ASSIGNED|RESOLVED
 Resolution||FIXED

--- Comment #5 from Richard Guenther  2010-10-14 
15:55:34 UTC ---
Fixed.

[Bug tree-optimization/44913] [4.6 Regression] -ftree-vectorize causes FAIL: gcc.dg/pr44838.c execution test

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=44913

--- Comment #4 from Richard Guenther  2010-10-14 
15:51:22 UTC ---
Author: rguenth
Date: Thu Oct 14 15:51:15 2010
New Revision: 165473

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=165473
Log:
2010-10-14  Richard Guenther  

PR tree-optimization/44913
* tree-data-ref.c (disjoint_objects_p): Remove.
(dr_may_alias_p): Simplify.  Only hand the base object to
the alias-oracle.
* tree-ssa-alias.c (ptr_deref_may_alias_decl_p): Handle
some more trees, bail out instead of asserting.
(ptr_derefs_may_alias_p): Likewise.  Export.
(refs_may_alias_p_1): Handle STRING_CSTs.
* tree-ssa-alias.h (ptr_derefs_may_alias_p): Declare.

* gcc.dg/torture/pr44913.c: New testcase.

Added:
trunk/gcc/testsuite/gcc.dg/torture/pr44913.c
Modified:
trunk/gcc/ChangeLog
trunk/gcc/testsuite/ChangeLog
trunk/gcc/tree-data-ref.c
trunk/gcc/tree-ssa-alias.c
trunk/gcc/tree-ssa-alias.h

[Bug tree-optimization/44913] [4.6 Regression] -ftree-vectorize causes FAIL: gcc.dg/pr44838.c execution test

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=44913

Richard Guenther  changed:

   What|Removed |Added

 Status|NEW |ASSIGNED
 AssignedTo|unassigned at gcc dot   |rguenth at gcc dot gnu.org
   |gnu.org |

--- Comment #3 from Richard Guenther  2010-10-14 
10:38:45 UTC ---
Mine.

[Bug tree-optimization/44913] [4.6 Regression] -ftree-vectorize causes FAIL: gcc.dg/pr44838.c execution test

[jakub at gcc dot gnu dot org]

-- 

jakub at gcc dot gnu dot org changed:

   What|Removed |Added

   Priority|P3  |P1


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=44913

[Bug tree-optimization/44913] [4.6 Regression] -ftree-vectorize causes FAIL: gcc.dg/pr44838.c execution test

[rguenth at gcc dot gnu dot org]

--- Comment #2 from rguenth at gcc dot gnu dot org  2010-07-23 12:35 ---
Confirmed.  We end up vectorizing

void
foo (int *a, int n)
{
  int *lasta = a + n;
  for (; a != lasta; a++)
{
  *a *= 2;
  a[1] = a[-1] + a[-2];
}
}

not seeing the dependence of *a vs a[-1] because via
initialize_data_dependence_relation we ask the alias-oracle whether
*a may alias a[-1] (which it doesn't).  So we end up not computing
a dependence distance.

May we not use the alias-oracle (on the full ref) here?


-- 

rguenth at gcc dot gnu dot org changed:

   What|Removed |Added

 CC||spop at gcc dot gnu dot org
 Status|UNCONFIRMED |NEW
 Ever Confirmed|0   |1
   Last reconfirmed|-00-00 00:00:00 |2010-07-23 12:35:43
   date||


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=44913

[Bug tree-optimization/44913] [4.6 Regression] -ftree-vectorize causes FAIL: gcc.dg/pr44838.c execution test

[hjl dot tools at gmail dot com]

--- Comment #1 from hjl dot tools at gmail dot com  2010-07-11 23:11 ---
This is caused by revision 161655:

http://gcc.gnu.org/ml/gcc-cvs/2010-07/msg6.html


-- 

hjl dot tools at gmail dot com changed:

   What|Removed |Added

 CC||rguenth at gcc dot gnu dot
   ||org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=44913

[Bug tree-optimization/44913] [4.6 Regression] -ftree-vectorize causes FAIL: gcc.dg/pr44838.c execution test

[rguenth at gcc dot gnu dot org]

-- 

rguenth at gcc dot gnu dot org changed:

   What|Removed |Added

   Keywords||wrong-code
   Target Milestone|--- |4.6.0


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=44913