Small Vectors Proposal

[Mikola Lysenko]

Oskar Linde wrote:
> For discussion, here is a not very thought out counter proposal:
> 
> 1. Make the D 2.0 static array pass-by-value instead of it's 
> inconsistent and strange pseudo-reference/value type heritage from C. 
> (Pass by reference could be retained for extern(C) functions only).
> 
> 2. Define ABIs for SSE2, SSE3, etc platforms so that small static arrays 
> can be allocated and passed in SIMD registers.
> 
> 3. Implement vector operations for static arrays.
> 

After thinking about it some more, I believe this approach would 
probably work just as well.  Another possibility is to simply restrict 
vectors to floating point types only:

ie, float2, float3, float4, double2, double3, double4, real2, real3, real4.

This makes the number of new types only 9 instead of 57.  The 
disadvantage is that it is no longer easy to use the MMX extensions 
which are specially tailored for integer vectors.  Overall, I guess I'd 
be happy with either situation.