Even x86, it would appear, wants to do aligned loads. I'm a little
surprised by that though maybe I shouldn't be as there is a RISC
implemented by the microcode under the x86 CPU.
I don't think there's ever been a CPU design where unaligned accesses run at the same speed as naturally aligned accesses. The worst case is an unaligned access that straddles a machine-word boundary.
-Paul W.