rustc_passes/
hir_id_validator.rs

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1use rustc_data_structures::sync::Lock;
2use rustc_hir as hir;
3use rustc_hir::def_id::LocalDefId;
4use rustc_hir::{HirId, ItemLocalId, intravisit};
5use rustc_index::bit_set::GrowableBitSet;
6use rustc_middle::hir::nested_filter;
7use rustc_middle::ty::TyCtxt;
8
9pub fn check_crate(tcx: TyCtxt<'_>) {
10    let errors = Lock::new(Vec::new());
11
12    tcx.par_hir_for_each_module(|module_id| {
13        let mut v =
14            HirIdValidator { tcx, owner: None, hir_ids_seen: Default::default(), errors: &errors };
15
16        tcx.hir_visit_item_likes_in_module(module_id, &mut v);
17    });
18
19    let errors = errors.into_inner();
20
21    if !errors.is_empty() {
22        let message = errors.iter().fold(String::new(), |s1, s2| s1 + "\n" + s2);
23        tcx.dcx().delayed_bug(message);
24    }
25}
26
27struct HirIdValidator<'a, 'hir> {
28    tcx: TyCtxt<'hir>,
29    owner: Option<hir::OwnerId>,
30    hir_ids_seen: GrowableBitSet<ItemLocalId>,
31    errors: &'a Lock<Vec<String>>,
32}
33
34impl<'a, 'hir> HirIdValidator<'a, 'hir> {
35    fn new_visitor(&self, tcx: TyCtxt<'hir>) -> HirIdValidator<'a, 'hir> {
36        HirIdValidator { tcx, owner: None, hir_ids_seen: Default::default(), errors: self.errors }
37    }
38
39    #[cold]
40    #[inline(never)]
41    fn error(&self, f: impl FnOnce() -> String) {
42        self.errors.lock().push(f());
43    }
44
45    fn check<F: FnOnce(&mut HirIdValidator<'a, 'hir>)>(&mut self, owner: hir::OwnerId, walk: F) {
46        assert!(self.owner.is_none());
47        self.owner = Some(owner);
48        walk(self);
49
50        if owner == hir::CRATE_OWNER_ID {
51            return;
52        }
53
54        // There's always at least one entry for the owning item itself
55        let max = self
56            .hir_ids_seen
57            .iter()
58            .map(|local_id| local_id.as_usize())
59            .max()
60            .expect("owning item has no entry");
61
62        if max != self.hir_ids_seen.len() - 1 {
63            let pretty_owner = self.tcx.hir_def_path(owner.def_id).to_string_no_crate_verbose();
64
65            let missing_items: Vec<_> = (0..=max as u32)
66                .map(|i| ItemLocalId::from_u32(i))
67                .filter(|&local_id| !self.hir_ids_seen.contains(local_id))
68                .map(|local_id| self.tcx.hir_id_to_string(HirId { owner, local_id }))
69                .collect();
70
71            let seen_items: Vec<_> = self
72                .hir_ids_seen
73                .iter()
74                .map(|local_id| self.tcx.hir_id_to_string(HirId { owner, local_id }))
75                .collect();
76
77            self.error(|| {
78                format!(
79                    "ItemLocalIds not assigned densely in {pretty_owner}. \
80            Max ItemLocalId = {max}, missing IDs = {missing_items:#?}; seen IDs = {seen_items:#?}"
81                )
82            });
83        }
84    }
85
86    fn check_nested_id(&mut self, id: LocalDefId) {
87        let Some(owner) = self.owner else { return };
88        let def_parent = self.tcx.local_parent(id);
89        let def_parent_hir_id = self.tcx.local_def_id_to_hir_id(def_parent);
90        if def_parent_hir_id.owner != owner {
91            self.error(|| {
92                format!(
93                    "inconsistent Def parent at `{:?}` for `{:?}`:\nexpected={:?}\nfound={:?}",
94                    self.tcx.def_span(id),
95                    id,
96                    owner,
97                    def_parent_hir_id
98                )
99            });
100        }
101    }
102}
103
104impl<'a, 'hir> intravisit::Visitor<'hir> for HirIdValidator<'a, 'hir> {
105    type NestedFilter = nested_filter::OnlyBodies;
106
107    fn maybe_tcx(&mut self) -> Self::MaybeTyCtxt {
108        self.tcx
109    }
110
111    fn visit_nested_item(&mut self, id: hir::ItemId) {
112        self.check_nested_id(id.owner_id.def_id);
113    }
114
115    fn visit_nested_trait_item(&mut self, id: hir::TraitItemId) {
116        self.check_nested_id(id.owner_id.def_id);
117    }
118
119    fn visit_nested_impl_item(&mut self, id: hir::ImplItemId) {
120        self.check_nested_id(id.owner_id.def_id);
121    }
122
123    fn visit_nested_foreign_item(&mut self, id: hir::ForeignItemId) {
124        self.check_nested_id(id.owner_id.def_id);
125    }
126
127    fn visit_item(&mut self, i: &'hir hir::Item<'hir>) {
128        let mut inner_visitor = self.new_visitor(self.tcx);
129        inner_visitor.check(i.owner_id, |this| intravisit::walk_item(this, i));
130    }
131
132    fn visit_id(&mut self, hir_id: HirId) {
133        let owner = self.owner.expect("no owner");
134
135        if owner != hir_id.owner {
136            self.error(|| {
137                format!(
138                    "HirIdValidator: The recorded owner of {} is {} instead of {}",
139                    self.tcx.hir_id_to_string(hir_id),
140                    self.tcx.hir_def_path(hir_id.owner.def_id).to_string_no_crate_verbose(),
141                    self.tcx.hir_def_path(owner.def_id).to_string_no_crate_verbose()
142                )
143            });
144        }
145
146        self.hir_ids_seen.insert(hir_id.local_id);
147    }
148
149    fn visit_foreign_item(&mut self, i: &'hir hir::ForeignItem<'hir>) {
150        let mut inner_visitor = self.new_visitor(self.tcx);
151        inner_visitor.check(i.owner_id, |this| intravisit::walk_foreign_item(this, i));
152    }
153
154    fn visit_trait_item(&mut self, i: &'hir hir::TraitItem<'hir>) {
155        let mut inner_visitor = self.new_visitor(self.tcx);
156        inner_visitor.check(i.owner_id, |this| intravisit::walk_trait_item(this, i));
157    }
158
159    fn visit_impl_item(&mut self, i: &'hir hir::ImplItem<'hir>) {
160        let mut inner_visitor = self.new_visitor(self.tcx);
161        inner_visitor.check(i.owner_id, |this| intravisit::walk_impl_item(this, i));
162    }
163
164    fn visit_pattern_type_pattern(&mut self, p: &'hir hir::TyPat<'hir>) {
165        intravisit::walk_ty_pat(self, p)
166    }
167}
rustc_passes/hir_id_validator.rs

rustc_passes/
hir_id_validator.rs
