- // MIR for `mutate_discriminant` before JumpThreading + // MIR for `mutate_discriminant` after JumpThreading fn mutate_discriminant() -> u8 { let mut _0: u8; let mut _1: std::option::Option; let mut _2: isize; bb0: { discriminant(_1) = 1; (((_1 as variant#1).0: NonZeroUsize).0: usize) = const 0_usize; _2 = discriminant(_1); switchInt(copy _2) -> [0: bb1, otherwise: bb2]; } bb1: { _0 = const 1_u8; return; } bb2: { _0 = const 2_u8; unreachable; } }