Altivec + 16 byte alignment

[Neil Booth]

Richard Kenner wrote:-

>     Exactly, but now it seems *you're* the one arguing for putting the
>     check in the front end.
> 
> Not necessarily: it can be checked when laying out the type in stor-layout.c.

stor-layout.c is part of the front end; it just happens to be part of
GCC that is shared between all front ends.  And it shows - it's overly
generic and nearly incomprehensible.

The C parser I'm working on won't use it to lay out types, since I don't
use trees.  I'll have to ensure that what stor-layout.c does (during
lowering) is the same as what I've done.  At least in an initial
implementation.

Neil.