-O3 and -ftree-vectorize

[Uros Bizjak]

Hello!

4.9 does not enable -ftree-vectorize for -O3 (and Ofast) anymore. Is
this intentional?

$/ssd/uros/gcc-build/gcc/xgcc -B /ssd/uros/gcc-build/gcc -O3 -Q
--help=optimizers

...
-ftree-vectorize                      [disabled]
...

This is the reason for low scores on SciMark v2.0 as conducted by
Phoronix. Please see comment #18 in [1].

[1] http://phoronix.com/forums/showthread.php?95147-Clang-s-Competition-For-GCC-On-Intel-Haswell/page2

Uros.