Disable vectorization on pre SSE2

[Benjamin Kramer]

On 05.03.2014, at 18:02, Arnold Schwaighofer <aschwaighofer at apple.com> wrote:

> Hi all,
> 
> does anyone have objections against disabling vectorization on pre SSE2 architectures. I don’t think we have bots testing this and so bugs are likely (see PR18036). We fail in isel for a simple vector select.

This is the right thing to do, getting the bugs fixed would also be a good thing :)

- Ben