[cxx-abi-dev] mangling vector types

[Mark Mitchell]

Jason Merrill wrote:

> to represent the type of vec in an element-based mangling, the number of
> elements would need to be expressed as I/sizeof(T), which is not more
> compact.
> 
> That, and the fact that vector_size takes a number of bytes rather than
> elements suggests that maybe the former is more natural for working with
> vector hardware.

>From a language-design point of view, I don't understand why we're using
bytes there.  It seems unnecessarily low-level.  So, using a byte-based
mangling seems consistent with GCC's language extension, but I'm not
sure why that's a particularly good language extension.  Of course, if
it's a language extension that everyone has accepted and is therefore
standard (not in the ISO sense, but in the everyone-does-it sense), then
abstract goodness is irrelevant.

-- 
Mark Mitchell
CodeSourcery
mark at codesourcery.com
(650) 331-3385 x713