[Bug target/38306] [4.4/4.5/4.6 Regression] 15% slowdown w.r.t. 4.3 of computational kernel on some architectures

Joost.VandeVondele at pci dot uzh.ch gcc-bugzilla@gcc.gnu.org
Sun Feb 20 16:50:00 GMT 2011


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=38306

--- Comment #21 from Joost VandeVondele <Joost.VandeVondele at pci dot uzh.ch> 2011-02-20 16:32:38 UTC ---
... however, the following works great:

> gfortran -O2 -march=native -funroll-loops  -ffast-math  -ftree-vectorize test.f90 ; ./a.out 
Time for evaluation [s]:                        2.700

(notice -O2 instead of -O3, -O2 is thus twice as fast as -O3)



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