Dhrystone speed dmd vs gdc

downs default_357-line at yahoo.de
Sun Feb 25 06:31:33 PST 2007


Dave Wrote:

> downs wrote:
> > I just ran the samples/dhry.d compiled with DMD 1.007 vs GDC .23 svn on gcc 4.1.1 using MinGW, on a Pentium M with 1.6g.
> > The used flags were -O -release -inline for DMD and -ffast-math -O3 -frelease -finline-functions for GDC.
> > The observed VAX MIPS ratings were 3280 for GDC, but only 2570 for DMD.
> > (Note that the GDC rating could be increased to 3480 by adding -msse -mfpmath=sse,387, but that is somewhat risky).
> > All tests were run with realtime priority.
> > Do you think this difference in a synthetic benchmark translates into an actual speed difference for real-world applications?
> > Did I miss any DMD compiler flags?
> > Greetings   --downs
> 
> The DMD version maybe using a higher resolution timer -- GetTickCount() vs time() for the GDC 
> version. If so, that may have a lot to do with it.
> 
> On a P4 linux box, if I use an external timer ('time'), DMD consistently outperforms GDC with the 
> switches above by about 15% or so.
I tried the same thing.
18,219s for GDC vs 22,422s for DMD. So the difference seems less, but it's still there.



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