[Bug tree-optimization/53346] [4.6/4.7/4.8 Regression] Bad vectorization in the proc cptrf2 of rnflow.f90

[dominiq at lps dot ens.fr]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53346

--- Comment #9 from Dominique d'Humieres <dominiq at lps dot ens.fr> 2012-05-18 14:49:22 UTC ---
> Unfortunately, the loop in original rnflow test still gets vectorized, with no
> change in the runtime:

Confirmed, at revision 187655 I still get

-O2                      21.8
-O2 -ftree-vectorize     27.9
-O3                      25.2
-O3 -fno-tree-vectorize  21.4

Uneducated guess: is it possible that failed attempts to vectorize may mess up
further optimizations?