In nightly builds of Rust (on 64-bit x86 platforms; no idea about support elsewhere), `(a as u128) * (b as u128)` where `a` and `b` are 64-bit integers will com

In nightly builds of Rust (on 64-bit x86 platforms; no idea about support elsewhere), `(a as u128) * (b as u128)` where `a` and `b` are 64-bit integers will compile to a single `mul` instruction: see https://godbolt.org/g/Be7ncs https://godbolt.org/g/Be7ncs