Tim Prince <n8tm@xxxxxxx> writes: > You would require _attribute__(aligned) and similar gcc extensions to > inform the compiler about alignments so as to enable more use of aligned > instructions. Without those, it's not practical to auto-vectorize short > loops, except by explicit low-level coding (e.g. sse intrinsics). In > any case, a loop of trip 9 might not be efficiently vectorizable. The problem I had when I played with this sort of thing before, was not gcc, but libc, which doesn't align general allocations enough for SSE (and I gather the libc devs have no intention of adding such a feature), so one needs to jump through a lot of hoops to make sure heap-allocated stuff is aligned properly. It seemed like a big pain ... -Miles -- Suburbia: where they tear out the trees and then name streets after them.
