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From: "burnus at gcc dot gnu dot org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug fortran/32512] efficiency of RESHAPE and SPREAD
Date: Tue, 26 Jun 2007 11:54:00 -0000	[thread overview]
Message-ID: <20070626115421.2634.qmail@sourceware.org> (raw)
In-Reply-To: <bug-32512-14211@http.gcc.gnu.org/bugzilla/>



------- Comment #3 from burnus at gcc dot gnu dot org  2007-06-26 11:54 -------
Just to show how much time can be saved, I compared the speed with different
compilers (on x86-64/Linux):

gfortran sunstudio12  ifort9.1/10 open64  NAGf95  g95
-------------------------------------------------------
 0.024   0.02575      0.024       0.024   0.03    0.028 (1)
 0.028   0.025365     0.024       0.024   0.03    0.028 (2)
 6.12    0.025514     2.420       0.024   2.59   21.373 (3)
10.47    4.307007   18.4371       2.616  11.58   10.660 (4)
-------------------------------------------------------
(1) matrix_op(a), (2) matrix_op(transpose(a))
(3) matrix_op(reshape(b,shape=(/n,n+1/)))
(4) matrix_op(spread(c,dim=1,ncopies=n))

Thus especially RESHAPE has a huge potential.


-- 

burnus at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |burnus at gcc dot gnu dot
                   |                            |org
             Status|UNCONFIRMED                 |NEW
     Ever Confirmed|0                           |1
   Last reconfirmed|0000-00-00 00:00:00         |2007-06-26 11:54:21
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=32512


  parent reply	other threads:[~2007-06-26 11:54 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2007-06-26  6:28 [Bug fortran/32512] New: " highegg at gmail dot com
2007-06-26  6:36 ` [Bug fortran/32512] " highegg at gmail dot com
2007-06-26 10:56 ` highegg at gmail dot com
2007-06-26 11:54 ` burnus at gcc dot gnu dot org [this message]
2008-03-28 23:24 ` tkoenig at gcc dot gnu dot org
2008-04-13 20:17 ` tkoenig at gcc dot gnu dot org
2008-11-30 19:54 ` pault at gcc dot gnu dot org
2010-05-09 18:43 ` dfranke at gcc dot gnu dot org

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