Altivec + 16 byte alignment

[Richard Kenner]

    It's just a function call, exposed to the front end.  Nice and clean.

In which case, why not do it totally in the back end?  I don't see it as
a big deal, but I'm not sure what you gain by adding a call to that function
into every front end.

    > And then you have the problem of alignment of *types*, where you have to
    > be able to guarantee the alignment for both stack and memory.

    Why is that a problem?

It isn't necessarily, just another case to be concerned about.