// 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 _4: &std::option::Option; let mut _7: bool; let mut _8: u32; scope 2 { } scope 3 (inlined Option::::is_none) { debug self => _4; let mut _6: bool; scope 4 (inlined Option::::is_some) { debug self => _4; let mut _5: isize; } } scope 5 (inlined core::num::::wrapping_add) { debug self => _1; debug rhs => _8; } } bb0: { StorageLive(_7); StorageLive(_4); StorageLive(_3); _3 = ::forward_checked(_1, _2) -> [return: bb1, unwind continue]; } bb1: { _4 = &_3; StorageLive(_6); _5 = discriminant((*_4)); _6 = Eq(_5, const 1_isize); _7 = Not(move _6); StorageDead(_6); StorageDead(_3); StorageDead(_4); switchInt(move _7) -> [0: bb3, otherwise: bb2]; } bb2: { assert(!const true, "attempt to compute `{} + {}`, which would overflow", const _, const 1_u32) -> [success: bb3, unwind continue]; } bb3: { StorageDead(_7); StorageLive(_8); _8 = _2 as u32 (IntToInt); _0 = Add(_1, _8); StorageDead(_8); return; } }