// MIR for `forward_loop` after PreCodegen

fn forward_loop(_1: u32, _2: u32, _3: impl Fn(u32)) -> () {
    debug start => _1;
    debug end => _2;
    debug f => _3;
    let mut _0: ();
    let mut _4: u32;
    let mut _7: std::option::Option<u32>;
    let mut _10: isize;
    let mut _12: &impl Fn(u32);
    let mut _13: (u32,);
    let _14: ();
    scope 1 {
        debug iter => std::ops::Range<u32>{ .0 => _4, .1 => _2, };
        let _11: u32;
        scope 2 {
            debug x => _11;
        }
        scope 4 (inlined iter::range::<impl Iterator for std::ops::Range<u32>>::next) {
            debug self => &std::ops::Range<u32>{ .0 => _4, .1 => _2, };
            scope 5 (inlined <std::ops::Range<u32> as iter::range::RangeIteratorImpl>::spec_next) {
                debug self => &std::ops::Range<u32>{ .0 => _4, .1 => _2, };
                let mut _6: bool;
                let _8: u32;
                let mut _9: u32;
                scope 6 {
                    debug old => _8;
                    scope 7 {
                    }
                }
                scope 8 (inlined cmp::impls::<impl PartialOrd for u32>::lt) {
                    debug self => &_4;
                    debug other => &_2;
                    let mut _5: u32;
                }
            }
        }
    }
    scope 3 (inlined <std::ops::Range<u32> as IntoIterator>::into_iter) {
        debug self => std::ops::Range<u32>{ .0 => _1, .1 => _2, };
    }

    bb0: {
        StorageLive(_4);
        _4 = _1;
        goto -> bb1;
    }

    bb1: {
        StorageLive(_7);
        StorageLive(_8);
        StorageLive(_6);
        StorageLive(_5);
        _5 = _4;
        _6 = Lt(move _5, _2);
        StorageDead(_5);
        switchInt(move _6) -> [0: bb2, otherwise: bb3];
    }

    bb2: {
        _7 = Option::<u32>::None;
        goto -> bb5;
    }

    bb3: {
        _8 = _4;
        StorageLive(_9);
        _9 = <u32 as Step>::forward_unchecked(_8, const 1_usize) -> [return: bb4, unwind: bb11];
    }

    bb4: {
        _4 = move _9;
        StorageDead(_9);
        _7 = Option::<u32>::Some(_8);
        goto -> bb5;
    }

    bb5: {
        StorageDead(_6);
        StorageDead(_8);
        _10 = discriminant(_7);
        switchInt(move _10) -> [0: bb6, 1: bb8, otherwise: bb10];
    }

    bb6: {
        StorageDead(_7);
        StorageDead(_4);
        drop(_3) -> [return: bb7, unwind continue];
    }

    bb7: {
        return;
    }

    bb8: {
        _11 = ((_7 as Some).0: u32);
        StorageLive(_12);
        _12 = &_3;
        StorageLive(_13);
        _13 = (_11,);
        _14 = <impl Fn(u32) as Fn<(u32,)>>::call(move _12, move _13) -> [return: bb9, unwind: bb11];
    }

    bb9: {
        StorageDead(_13);
        StorageDead(_12);
        StorageDead(_7);
        goto -> bb1;
    }

    bb10: {
        unreachable;
    }

    bb11 (cleanup): {
        drop(_3) -> [return: bb12, unwind terminate];
    }

    bb12 (cleanup): {
        resume;
    }
}