[cfe-dev] improved vector bool/pixel support

[Chris Lattner]

On Jul 6, 2010, at 1:46 PM, Douglas Gregor wrote:

>> I'm happy to defer to Doug's opinion here.  However, I thought that the idea of a canonical type was that it represent the structural behavior of the type.  Semantically there should be no difference between the sugared and desugared type.  If "altivec" vectors have more behavior than just how they print, I don't think it's just sugar, right?
> 
> 
> Do AltiVec vectors have more/different behavior from than GCC vectors? I honestly don't know. If they do, they need their own canonical types and we'll need to introduce appropriate implicit conversions between the two kinds of vectors. If the behavior is the same, then it's just sugar.

Yes, they do.  For example, 

my_altivec_vector x = {1} does a splat, not a zero fill.

-Chris