[Bug tree-optimization/43657] [4.3/4.4/4.5/4.6 Regression] -ftree-loop-linear causes FAIL: gcc.dg/vect/vect-cond-5.c execution test

[Bug tree-optimization/43657] [4.3/4.4/4.5/4.6 Regression] -ftree-loop-linear causes FAIL: gcc.dg/vect/vect-cond-5.c execution test

[changpeng.fang at amd dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43657

--- Comment #4 from Changpeng Fang <changpeng.fang at amd dot com> 2010-10-19 21:27:46 UTC ---
 for (k = 0; k < 32; k++)
    {
      res = 0;
      for (j = 0; j < 32; j++) 
        for (i = 0; i < 32; i++)
          { 
            next = a[i][j]; 
            res = c > cond_array[i+k][j] ? next : res;
          }

      out[k] = res;
    }


gcc interchanges i and j loops, which is not legal in this case.
Apparently, res takes the last value of a[i][j] that satisfies the 
condition c > cond_array[i+k][j]. As a result, change in the 
reference order will get a different value for res.

Anyone knows where to do this legality check?

What about the interchange in Graphite for this case?

[Bug tree-optimization/43657] [4.3/4.4/4.5/4.6 Regression] -ftree-loop-linear causes FAIL: gcc.dg/vect/vect-cond-5.c execution test

[aoliva at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43657

Alexandre Oliva <aoliva at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |ASSIGNED
   Last reconfirmed|                            |2011.01.16 11:50:32
                 CC|                            |aoliva at gcc dot gnu.org
      Known to work|                            |
         AssignedTo|unassigned at gcc dot       |aoliva at gcc dot gnu.org
                   |gnu.org                     |
     Ever Confirmed|0                           |1
      Known to fail|                            |

--- Comment #5 from Alexandre Oliva <aoliva at gcc dot gnu.org> 2011-01-16 11:50:32 UTC ---
Been looking into this.  There doesn't seem to be anything to prevent the loop
from being transformed when an SSA DEF escapes the loop.  Trying to fix.

[Bug tree-optimization/43657] [4.3/4.4/4.5/4.6 Regression] -ftree-loop-linear causes FAIL: gcc.dg/vect/vect-cond-5.c execution test

[aoliva at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43657

--- Comment #6 from Alexandre Oliva <aoliva at gcc dot gnu.org> 2011-01-16 12:29:18 UTC ---
Created attachment 22982
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=22982
Proposed patch

This avoids the transformation, but...  Is the test too strict?  My reasoning
is that, since we're in closed form (right?), the exit block will only have
PHIs for stuff that is changed wthin the loop and is used outside the loop. 
Does that sound sound? :-)

[Bug tree-optimization/43657] [4.3/4.4/4.5/4.6 Regression] -ftree-loop-linear causes FAIL: gcc.dg/vect/vect-cond-5.c execution test

[spop at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43657

--- Comment #7 from Sebastian Pop <spop at gcc dot gnu.org> 2011-01-18 20:54:38 UTC ---
Author: spop
Date: Tue Jan 18 20:54:34 2011
New Revision: 168964

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=168964
Log:
Add testcase for PR43657.

2011-01-18  Sebastian Pop  <sebastian.pop@amd.com>

    PR tree-optimization/43657
    * gcc.dg/graphite/pr43657.c: New.

Added:
    branches/graphite/gcc/testsuite/gcc.dg/graphite/pr43657.c
Modified:
    branches/graphite/gcc/ChangeLog.graphite

[Bug tree-optimization/43657] [4.3/4.4/4.5/4.6 Regression] -ftree-loop-linear causes FAIL: gcc.dg/vect/vect-cond-5.c execution test

[spop at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43657

Sebastian Pop <spop at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
         AssignedTo|aoliva at gcc dot gnu.org   |spop at gcc dot gnu.org

--- Comment #8 from Sebastian Pop <spop at gcc dot gnu.org> 2011-01-18 20:55:48 UTC ---
Fixed on the graphite branch.

[Bug tree-optimization/43657] [4.3/4.4/4.5/4.6 Regression] -ftree-loop-linear causes FAIL: gcc.dg/vect/vect-cond-5.c execution test

[spop at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43657

--- Comment #9 from Sebastian Pop <spop at gcc dot gnu.org> 2011-01-25 21:25:05 UTC ---
Author: spop
Date: Tue Jan 25 21:24:53 2011
New Revision: 169254

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=169254
Log:
Add testcase for PR43657.

2011-01-18  Sebastian Pop  <sebastian.pop@amd.com>

    PR tree-optimization/43657
    * gcc.dg/graphite/pr43657.c: New.

Added:
    trunk/gcc/testsuite/gcc.dg/graphite/pr43657.c
Modified:
    trunk/gcc/testsuite/ChangeLog

[Bug tree-optimization/43657] [4.3/4.4/4.5/4.6 Regression] -ftree-loop-linear causes FAIL: gcc.dg/vect/vect-cond-5.c execution test

[spop at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43657

Sebastian Pop <spop at gcc dot gnu.org> changed:

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

--- Comment #10 from Sebastian Pop <spop at gcc dot gnu.org> 2011-01-25 21:28:55 UTC ---
Fixed.

[Bug tree-optimization/43657] [4.3/4.4/4.5/4.6 Regression] -ftree-loop-linear causes FAIL: gcc.dg/vect/vect-cond-5.c execution test

[dnovillo at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43657

--- Comment #11 from Diego Novillo <dnovillo at gcc dot gnu.org> 2011-02-02 17:48:23 UTC ---
Author: dnovillo
Date: Wed Feb  2 17:48:17 2011
New Revision: 169593

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=169593
Log:
Add testcase for PR43657.

2011-01-18  Sebastian Pop  <sebastian.pop@amd.com>

    PR tree-optimization/43657
    * gcc.dg/graphite/pr43657.c: New.

Added:
    branches/google/integration/gcc/testsuite/gcc.dg/graphite/pr43657.c
Modified:
    branches/google/integration/gcc/testsuite/ChangeLog

[Bug tree-optimization/43657] [4.3/4.4/4.5/4.6 Regression] -ftree-loop-linear causes FAIL: gcc.dg/vect/vect-cond-5.c execution test

[jakub at gcc dot gnu dot org]

------- Comment #3 from jakub at gcc dot gnu dot org  2010-05-26 11:15 -------
Created an attachment (id=20748)
 --> (http://gcc.gnu.org/bugzilla/attachment.cgi?id=20748&action=view)
pr43657.c

Slightly adjusted testcase.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43657

[Bug tree-optimization/43657] [4.3/4.4/4.5/4.6 Regression] -ftree-loop-linear causes FAIL: gcc.dg/vect/vect-cond-5.c execution test

[rguenth at gcc dot gnu dot org]

------- Comment #2 from rguenth at gcc dot gnu dot org  2010-05-22 18:13 -------
GCC 4.3.5 is being released, adjusting target milestone.


-- 

rguenth at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|4.3.5                       |4.3.6


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43657

[Bug tree-optimization/43657] [4.3/4.4/4.5/4.6 Regression] -ftree-loop-linear causes FAIL: gcc.dg/vect/vect-cond-5.c execution test

[rguenth at gcc dot gnu dot org]

-- 

rguenth at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Priority|P3                          |P2


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43657