>> This not only ensures correct 32 bit integer semantics (like wrapping around), but also helps the engines to use actual integer instructions in the generated machine code.

But there is only one type of number in javascript. Everything is just a double(BigInt aside). You get a 32-bit integer because the bitwise operator casts the result to one. c has the exact same semantics as any other js number.

Yeah there are tricks to convince the engine you are using an integral type but those unless you are doing a lot of benchmarks they aren't really useful. Any compilation tier can choose to use any intermediate representation it wants.