rust/tests/mir-opt/pre-codegen/slice_iter.reverse_loop.PreCodegen.after.panic-unwind.mir

// MIR for `reverse_loop` after PreCodegen

fn reverse_loop(_1: &[T], _2: impl Fn(&T)) -> () {
    debug slice => _1;
    debug f => _2;
    let mut _0: ();
    let mut _12: std::slice::Iter<'_, T>;
    let mut _13: std::iter::Rev<std::slice::Iter<'_, T>>;
    let mut _14: std::iter::Rev<std::slice::Iter<'_, T>>;
    let mut _35: std::option::Option<&T>;
    let mut _37: &impl Fn(&T);
    let mut _38: (&T,);
    let _39: ();
    scope 1 {
        debug iter => _14;
        let _36: &T;
        scope 2 {
            debug x => _36;
        }
        scope 18 (inlined <Rev<std::slice::Iter<'_, T>> as Iterator>::next) {
            scope 19 (inlined <std::slice::Iter<'_, T> as DoubleEndedIterator>::next_back) {
                let mut _15: *const T;
                let mut _20: bool;
                let mut _21: *const T;
                let _34: &T;
                scope 20 {
                    let _16: std::ptr::NonNull<T>;
                    let _22: usize;
                    scope 21 {
                    }
                    scope 22 {
                        scope 25 (inlined <NonNull<T> as PartialEq>::eq) {
                            let mut _17: std::ptr::NonNull<T>;
                            let mut _18: *mut T;
                            let mut _19: *mut T;
                            scope 26 (inlined NonNull::<T>::as_ptr) {
                            }
                            scope 27 (inlined NonNull::<T>::as_ptr) {
                            }
                        }
                    }
                    scope 23 (inlined std::ptr::const_ptr::<impl *const T>::addr) {
                        scope 24 (inlined std::ptr::const_ptr::<impl *const T>::cast::<()>) {
                        }
                    }
                }
                scope 28 (inlined std::slice::Iter::<'_, T>::next_back_unchecked) {
                    let _28: std::ptr::NonNull<T>;
                    scope 29 (inlined std::slice::Iter::<'_, T>::pre_dec_end) {
                        let mut _23: *mut *const T;
                        let mut _24: *mut std::ptr::NonNull<T>;
                        let mut _25: std::ptr::NonNull<T>;
                        let mut _29: *mut *const T;
                        let mut _30: *mut usize;
                        let mut _31: usize;
                        let mut _32: usize;
                        scope 30 {
                            scope 31 {
                            }
                            scope 32 {
                                scope 35 (inlined NonNull::<T>::sub) {
                                    scope 36 (inlined #[track_caller] core::num::<impl isize>::unchecked_neg) {
                                        scope 37 (inlined core::ub_checks::check_language_ub) {
                                            scope 38 (inlined core::ub_checks::check_language_ub::runtime) {
                                            }
                                        }
                                    }
                                    scope 39 (inlined NonNull::<T>::offset) {
                                        let mut _26: *mut T;
                                        let mut _27: *mut T;
                                        scope 40 (inlined NonNull::<T>::as_ptr) {
                                        }
                                    }
                                }
                            }
                            scope 33 (inlined std::ptr::mut_ptr::<impl *mut *const T>::cast::<usize>) {
                            }
                            scope 34 (inlined std::ptr::mut_ptr::<impl *mut *const T>::cast::<NonNull<T>>) {
                            }
                        }
                    }
                    scope 41 (inlined NonNull::<T>::as_ref::<'_>) {
                        let _33: *const T;
                        scope 42 (inlined NonNull::<T>::as_ptr) {
                        }
                        scope 43 (inlined std::ptr::mut_ptr::<impl *mut T>::cast_const) {
                        }
                    }
                }
            }
        }
    }
    scope 3 (inlined core::slice::<impl [T]>::iter) {
        scope 4 (inlined std::slice::Iter::<'_, T>::new) {
            let _3: usize;
            let mut _5: std::ptr::NonNull<[T]>;
            let mut _9: *mut T;
            let mut _10: *mut T;
            scope 5 {
                let _8: std::ptr::NonNull<T>;
                scope 6 {
                    let _11: *const T;
                    scope 7 {
                    }
                    scope 11 (inlined std::ptr::without_provenance::<T>) {
                        scope 12 (inlined without_provenance_mut::<T>) {
                        }
                    }
                    scope 13 (inlined NonNull::<T>::as_ptr) {
                    }
                    scope 14 (inlined #[track_caller] std::ptr::mut_ptr::<impl *mut T>::add) {
                    }
                }
                scope 8 (inlined NonNull::<[T]>::from_ref) {
                    let mut _4: *const [T];
                }
                scope 9 (inlined NonNull::<[T]>::cast::<T>) {
                    let mut _6: *mut [T];
                    let mut _7: *mut T;
                    scope 10 (inlined NonNull::<[T]>::as_ptr) {
                    }
                }
            }
        }
    }
    scope 15 (inlined <std::slice::Iter<'_, T> as Iterator>::rev) {
        scope 16 (inlined Rev::<std::slice::Iter<'_, T>>::new) {
        }
    }
    scope 17 (inlined <Rev<std::slice::Iter<'_, T>> as IntoIterator>::into_iter) {
    }

    bb0: {
        StorageLive(_12);
        StorageLive(_3);
        StorageLive(_8);
        StorageLive(_11);
        _3 = PtrMetadata(copy _1);
        StorageLive(_5);
        StorageLive(_4);
        _4 = &raw const (*_1);
        _5 = copy _4 as std::ptr::NonNull<[T]> (Transmute);
        StorageDead(_4);
        StorageLive(_7);
        StorageLive(_6);
        _6 = copy _5 as *mut [T] (Transmute);
        _7 = copy _6 as *mut T (PtrToPtr);
        StorageDead(_6);
        _8 = copy _7 as std::ptr::NonNull<T> (Transmute);
        StorageDead(_7);
        StorageDead(_5);
        switchInt(const <T as std::mem::SizedTypeProperties>::IS_ZST) -> [0: bb1, otherwise: bb2];
    }

    bb1: {
        StorageLive(_10);
        StorageLive(_9);
        _9 = copy _8 as *mut T (Transmute);
        _10 = Offset(copy _9, copy _3);
        StorageDead(_9);
        _11 = copy _10 as *const T (PtrToPtr);
        StorageDead(_10);
        goto -> bb3;
    }

    bb2: {
        _11 = copy _3 as *const T (Transmute);
        goto -> bb3;
    }

    bb3: {
        _12 = std::slice::Iter::<'_, T> { ptr: copy _8, end_or_len: copy _11, _marker: const ZeroSized: PhantomData<&T> };
        StorageDead(_11);
        StorageDead(_8);
        StorageDead(_3);
        _13 = Rev::<std::slice::Iter<'_, T>> { iter: copy _12 };
        StorageDead(_12);
        StorageLive(_14);
        _14 = copy _13;
        goto -> bb4;
    }

    bb4: {
        StorageLive(_35);
        StorageLive(_22);
        StorageLive(_21);
        StorageLive(_16);
        StorageLive(_34);
        StorageLive(_20);
        switchInt(const <T as std::mem::SizedTypeProperties>::IS_ZST) -> [0: bb5, otherwise: bb6];
    }

    bb5: {
        StorageLive(_15);
        _15 = copy ((_14.0: std::slice::Iter<'_, T>).1: *const T);
        _16 = copy _15 as std::ptr::NonNull<T> (Transmute);
        StorageDead(_15);
        StorageLive(_18);
        StorageLive(_17);
        _17 = copy ((_14.0: std::slice::Iter<'_, T>).0: std::ptr::NonNull<T>);
        _18 = copy _17 as *mut T (Transmute);
        StorageDead(_17);
        StorageLive(_19);
        _19 = copy _16 as *mut T (Transmute);
        _20 = Eq(copy _18, copy _19);
        StorageDead(_19);
        StorageDead(_18);
        goto -> bb7;
    }

    bb6: {
        _21 = copy ((_14.0: std::slice::Iter<'_, T>).1: *const T);
        _22 = copy _21 as usize (Transmute);
        _20 = Eq(copy _22, const 0_usize);
        goto -> bb7;
    }

    bb7: {
        switchInt(move _20) -> [0: bb8, otherwise: bb17];
    }

    bb8: {
        StorageLive(_28);
        StorageLive(_30);
        StorageLive(_24);
        StorageLive(_25);
        switchInt(const <T as std::mem::SizedTypeProperties>::IS_ZST) -> [0: bb9, otherwise: bb12];
    }

    bb9: {
        StorageLive(_23);
        _23 = &raw mut ((_14.0: std::slice::Iter<'_, T>).1: *const T);
        _24 = copy _23 as *mut std::ptr::NonNull<T> (PtrToPtr);
        StorageDead(_23);
        _25 = copy (*_24);
        switchInt(const <T as std::mem::SizedTypeProperties>::IS_ZST) -> [0: bb10, otherwise: bb11];
    }

    bb10: {
        StorageLive(_27);
        StorageLive(_26);
        _26 = copy _25 as *mut T (Transmute);
        _27 = Offset(copy _26, const -1_isize);
        StorageDead(_26);
        _25 = copy _27 as std::ptr::NonNull<T> (Transmute);
        StorageDead(_27);
        goto -> bb11;
    }

    bb11: {
        (*_24) = move _25;
        _28 = copy (*_24);
        goto -> bb13;
    }

    bb12: {
        StorageLive(_29);
        _29 = &raw mut ((_14.0: std::slice::Iter<'_, T>).1: *const T);
        _30 = copy _29 as *mut usize (PtrToPtr);
        StorageDead(_29);
        StorageLive(_32);
        StorageLive(_31);
        _31 = copy (*_30);
        _32 = SubUnchecked(move _31, const 1_usize);
        StorageDead(_31);
        (*_30) = move _32;
        StorageDead(_32);
        _28 = copy ((_14.0: std::slice::Iter<'_, T>).0: std::ptr::NonNull<T>);
        goto -> bb13;
    }

    bb13: {
        StorageDead(_25);
        StorageDead(_24);
        StorageDead(_30);
        StorageLive(_33);
        _33 = copy _28 as *const T (Transmute);
        _34 = &(*_33);
        StorageDead(_33);
        StorageDead(_28);
        _35 = Option::<&T>::Some(copy _34);
        StorageDead(_20);
        StorageDead(_34);
        StorageDead(_16);
        StorageDead(_21);
        StorageDead(_22);
        _36 = copy ((_35 as Some).0: &T);
        StorageLive(_37);
        _37 = &_2;
        StorageLive(_38);
        _38 = (copy _36,);
        _39 = <impl Fn(&T) as Fn<(&T,)>>::call(move _37, move _38) -> [return: bb14, unwind: bb15];
    }

    bb14: {
        StorageDead(_38);
        StorageDead(_37);
        StorageDead(_35);
        goto -> bb4;
    }

    bb15 (cleanup): {
        drop(_2) -> [return: bb16, unwind terminate(cleanup)];
    }

    bb16 (cleanup): {
        resume;
    }

    bb17: {
        StorageDead(_20);
        StorageDead(_34);
        StorageDead(_16);
        StorageDead(_21);
        StorageDead(_22);
        StorageDead(_35);
        StorageDead(_14);
        drop(_2) -> [return: bb18, unwind continue];
    }

    bb18: {
        return;
    }
}