Just a general question that I can't seem to find a straight answer to anywhere. My use case is to use the
fst crate in a package targeting wasm. (I think) the
fst crate uses u64 arithmetic pervasively, but my use case for
fst would likely be okay with just
u32 (I have very few destinations).
What I think I know:
According to several different articles I was able to find, such as the answer on SO, below. Using a higher bit number on a lower bit processor will lead to the entire data of that number not fitting into a single register, which (IIUC) means that computation can result in multiple machine instructions.
Does this same performance difference exist on wasm32 while performing arithmetic with u64s? Even if the host is running on a 64bit processor?
I could imagine that the wasm runtime might make a difference, so I'm mostly concerned about how Chrome's WebAssembly runtime might perform.