Manu Evans: I appreciate your efforts. I answer to the OP that DMD doesn't yet offer most of the things discussed in this thread. But I think that it's better to add and work on high-performance features when the basics of D are in better shape. Currently there are more basic fishes to implement or debug, like tuples syntax sugar, module system issues, const issues, inout, and so on and on (on the other hand I agree that it's OK to discuss even now D design ideas that will allow that future high performance).
> Hardware vectors are NOT float[4]'s, they are a reference to an > 128bit hardware register upon which various vector operations may be > supported, they are probably aligned, and they are only accessible > in 128bit quantities. I think they should be explicitly defined as > such. What do you want to do when CPU with 256 bit registers appear? When they grow to 512 bit? To 1024? Do you want to keep adding specific types? How many things do you want to add to D in the next 15 years of CPU evolution? Bye, bearophile
