9.51.2.3 Signatures ................... Function signatures are specified with the 'signature' pseudo-opcode, followed by a simple function signature imitating a C++-mangled function type: 'F' followed by an optional 'v', then a sequence of 'i', 'l', 'f', and 'd' characters to mark i32, i64, f32, and f64 parameters, respectively; followed by a final 'E' to mark the end of the function signature.