[Bug fortran/40581] New: Missed optimization in scalar operators on arrays

[Bug fortran/40581] New: Missed optimization in scalar operators on arrays

[burnus at gcc dot gnu dot org]

Found at
http://groups.google.com/group/comp.lang.fortran/browse_thread/thread/b232bca9766094cc
which contains several tests:

- NR : Normal Routines
- ER : Elemental Routines
- NF : Normal Functions (scalar operators)
- EF : Elemental functions (vector operators)
- SC : Scalar Computation 

The interesting point is if one compares NF/NR or NF/ER.
Using ifort   11.1 with -O3 -xHost        the result is 1.16 or 1.03.
Using gfortran 4.5 with -O3 -march=native the result is 1.31 or 1.41
   using -funroll-loops -O3 -march=native               1.49 or 1.59
   using -fwhole-file   -O3 -march=native               1.33 or 1.42
   (latest draft patch posted to fortran@)

Expected: The NF version is faster.

In total, the result does not look bad for gfortran, however (AMD64):

gfortran -O3 -march=native -funroll-loops var_dep.f90 test.f90
 NR    2.0121260  2.1001320  1.9041190
 ER    1.8761170  1.9561219  1.8081129
 NF    3.1001940  3.2042003  3.0761924
 EF    2.6561656  2.6641660  2.6561661
 SC   2.00023651E-02  2.00023651E-02  1.60007477E-02

ifort -O3 -xHost var_dep.f90 test.f90

 NR    2.396150  2.364148  2.324145
 ER    2.224138  2.164135  2.172136
 NF    2.768173  2.720170  2.736171
 EF    2.592162  2.552160  2.560160
 SC   1.6001701E-02  2.0000458E-02  1.6000748E-02


-- 
           Summary: Missed optimization in scalar operators on arrays
           Product: gcc
           Version: 4.5.0
            Status: UNCONFIRMED
          Keywords: missed-optimization
          Severity: normal
          Priority: P3
         Component: fortran
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: burnus at gcc dot gnu dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40581

[Bug fortran/40581] Missed optimization in scalar operators on arrays

[pault at gcc dot gnu dot org]

------- Comment #1 from pault at gcc dot gnu dot org  2009-12-18 14:53 -------
What do you want to do with this, Tobias?

Confirmed

Paul


-- 

pault at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
     Ever Confirmed|0                           |1
   Last reconfirmed|0000-00-00 00:00:00         |2009-12-18 14:53:13
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40581

[Bug fortran/40581] Missed optimization in scalar operators on arrays

[dfranke at gcc dot gnu dot org]

------- Comment #2 from dfranke at gcc dot gnu dot org  2010-05-23 19:18 -------
(In reply to comment #1)
> What do you want to do with this, Tobias?

This PR is still somewhat sparse on detail of the nature of the problem?!


-- 

dfranke at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |dfranke at gcc dot gnu dot
                   |                            |org
             Status|NEW                         |WAITING


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40581

[Bug fortran/40581] Missed optimization in scalar operators on arrays

[dfranke at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40581

Daniel Franke <dfranke at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|WAITING                     |RESOLVED
         Resolution|                            |INVALID

--- Comment #3 from Daniel Franke <dfranke at gcc dot gnu.org> 2010-12-27 23:30:51 UTC ---
Still unclear what this is about. Closing.
Tobias, please reopen if you want to keep this.