// MIR for `step_forward` after PreCodegen fn step_forward(_1: u32, _2: usize) -> u32 { debug x => _1; debug n => _2; let mut _0: u32; scope 1 (inlined ::forward) { debug start => _1; debug n => _2; let _3: std::option::Option; let mut _6: bool; let mut _7: u32; scope 2 { } scope 3 (inlined Option::::is_none) { debug self => &_3; let mut _5: bool; scope 4 (inlined Option::::is_some) { debug self => &_3; let mut _4: isize; } } scope 5 (inlined core::num::::wrapping_add) { debug self => _1; debug rhs => _7; } } bb0: { StorageLive(_6); StorageLive(_3); _3 = ::forward_checked(_1, _2) -> [return: bb1, unwind continue]; } bb1: { StorageLive(_5); _4 = discriminant(_3); _5 = Eq(_4, const 1_isize); _6 = Not(move _5); StorageDead(_5); StorageDead(_3); switchInt(move _6) -> [0: bb3, otherwise: bb2]; } bb2: { assert(!const true, "attempt to compute `{} + {}`, which would overflow", const _, const 1_u32) -> [success: bb3, unwind continue]; } bb3: { StorageDead(_6); StorageLive(_7); _7 = _2 as u32 (IntToInt); _0 = Add(_1, _7); StorageDead(_7); return; } }