Some timings after LCM, resp. alignment of stack doubles on i686

Toon Moene toon@moene.indiv.nluug.nl
Tue Mar 23 22:26:00 GMT 1999


L.S.,

Here are some timings for our NWP code after addition of LCM and after
the alignment code for stack doubles went into egcs.

                  Pre-LCM            with LCM          with alignment

0SUPOBS TOOK :    0.30999946594      0.32000064850        0.31000041962
0DATACH TOOK :  147.2699890137     150.6799926758       148.7799987793
0ANAEVA TOOK :  214.6200103760     209.6599884033       200.5200042725
0GRPEVA TOOK : 1259.9199218750    1973.4698486328      1227.4000244141
0HUMSUP TOOK :    0.05993652344      0.05004882812        0.05004882812
0DATACH TOOK :   46.0799560547      46.5000000000        46.8900146484
0HUMEVA TOOK :   23.9699707031      23.1499023438        23.2700195312
0GRPEVA TOOK :   31.8000488281      32.6699218750        31.3900146484

See the fourth line !  This code contains _some_ DOUBLE PRECISION
variables and automatic arrays.  Apparently something in the LCM code
generation threw it off-alignment, which was repaired by the alignment
updates.

Unfortunately, the forecast code crashes (it generates NaNs and then
dies) since the LCM change; I'll have to dig into that.

HTH,

-- 
Toon Moene (toon@moene.indiv.nluug.nl)
Saturnushof 14, 3738 XG  Maartensdijk, The Netherlands
Phone: +31 346 214290; Fax: +31 346 214286
g77 Support: fortran@gnu.org; egcs: egcs-bugs@cygnus.com


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