Fake vectors should be aligned... when possible #108
Description
Else this shows with DMD or GDC with AVX emulated vectors are not aligned, and we want to perform SSE aligned operations on them.
Note that it won't work when allocated by GC => https://issues.dlang.org/show_bug.cgi?id=10826
Note that DMD doesn't align stack variable proper => https://issues.dlang.org/show_bug.cgi?id=16098