Re: Poor performance with GNAT-GPL-2017

[Emile <emile.lunardon@gmail.com>]

Le samedi 10 juin 2017 13:23:34 UTC+2, Charly a écrit :
> Hi,
> 
> when I found the new GNAT-GPL-2017 this morning I was happy and installed it at once.
> But I was rather disappointed about the poor performance.
> To be more precise:
> 
> When I switch to new hard- or software I allways check the performance with my private tool:
> It solves Rubics Tabgle https://www.jaapsch.net/puzzles/tangle.htm with an ada programm, using one task per core.
> 
> With GNAT-GPL-2016 (gcc 4.9.4) it took about 0,4 sec to find both solutions,
> with GNAT-GPL-2017 (gcc 6.3.1) it takes about 0,8 sec to find both solutions,
> which means the program is slower by a factor of 2.
> 
> In both cases I use the following options: 
> -O3 -gnatA -gnatn -funroll-loops -fPIC -gnatp -g -gnatW8 -gnatVn -mtune=amdfam10 -gnat12
> 
> Any ideas??
> 
> Sincerly
> Charly

Is it the 64 Bits Linux version of GNAT which presents this performance slow down ?