rustc_middle/ty/
typeck_results.rs

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1use std::collections::hash_map::Entry;
2use std::hash::Hash;
3use std::iter;
4
5use rustc_abi::{FieldIdx, VariantIdx};
6use rustc_data_structures::fx::{FxIndexMap, FxIndexSet};
7use rustc_data_structures::unord::{ExtendUnord, UnordItems, UnordSet};
8use rustc_errors::ErrorGuaranteed;
9use rustc_hir::def::{DefKind, Res};
10use rustc_hir::def_id::{DefId, LocalDefId, LocalDefIdMap};
11use rustc_hir::hir_id::OwnerId;
12use rustc_hir::{
13    self as hir, BindingMode, ByRef, HirId, ItemLocalId, ItemLocalMap, ItemLocalSet, Mutability,
14};
15use rustc_index::IndexVec;
16use rustc_macros::{HashStable, TyDecodable, TyEncodable, TypeFoldable, TypeVisitable};
17use rustc_session::Session;
18use rustc_span::Span;
19
20use super::RvalueScopes;
21use crate::hir::place::Place as HirPlace;
22use crate::infer::canonical::Canonical;
23use crate::mir::FakeReadCause;
24use crate::traits::ObligationCause;
25use crate::ty::{
26    self, BoundVar, CanonicalPolyFnSig, ClosureSizeProfileData, GenericArgKind, GenericArgs,
27    GenericArgsRef, Ty, UserArgs, tls,
28};
29
30#[derive(TyEncodable, TyDecodable, Debug, HashStable)]
31pub struct TypeckResults<'tcx> {
32    /// The `HirId::owner` all `ItemLocalId`s in this table are relative to.
33    pub hir_owner: OwnerId,
34
35    /// Resolved definitions for `<T>::X` associated paths and
36    /// method calls, including those of overloaded operators.
37    type_dependent_defs: ItemLocalMap<Result<(DefKind, DefId), ErrorGuaranteed>>,
38
39    /// Resolved field indices for field accesses in expressions (`S { field }`, `obj.field`)
40    /// or patterns (`S { field }`). The index is often useful by itself, but to learn more
41    /// about the field you also need definition of the variant to which the field
42    /// belongs, but it may not exist if it's a tuple field (`tuple.0`).
43    field_indices: ItemLocalMap<FieldIdx>,
44
45    /// Stores the types for various nodes in the AST. Note that this table
46    /// is not guaranteed to be populated outside inference. See
47    /// typeck::check::fn_ctxt for details.
48    node_types: ItemLocalMap<Ty<'tcx>>,
49
50    /// Stores the type parameters which were instantiated to obtain the type
51    /// of this node. This only applies to nodes that refer to entities
52    /// parameterized by type parameters, such as generic fns, types, or
53    /// other items.
54    node_args: ItemLocalMap<GenericArgsRef<'tcx>>,
55
56    /// This will either store the canonicalized types provided by the user
57    /// or the generic parameters that the user explicitly gave (if any) attached
58    /// to `id`. These will not include any inferred values. The canonical form
59    /// is used to capture things like `_` or other unspecified values.
60    ///
61    /// For example, if the user wrote `foo.collect::<Vec<_>>()`, then the
62    /// canonical generic parameters would include only `for<X> { Vec<X> }`.
63    ///
64    /// See also `AscribeUserType` statement in MIR.
65    user_provided_types: ItemLocalMap<CanonicalUserType<'tcx>>,
66
67    /// Stores the canonicalized types provided by the user. See also
68    /// `AscribeUserType` statement in MIR.
69    pub user_provided_sigs: LocalDefIdMap<CanonicalPolyFnSig<'tcx>>,
70
71    adjustments: ItemLocalMap<Vec<ty::adjustment::Adjustment<'tcx>>>,
72
73    /// Stores the actual binding mode for all instances of [`BindingMode`].
74    pat_binding_modes: ItemLocalMap<BindingMode>,
75
76    /// Top-level patterns incompatible with Rust 2024's match ergonomics. These will be translated
77    /// to a form valid in all Editions, either as a lint diagnostic or hard error.
78    rust_2024_migration_desugared_pats: ItemLocalMap<Rust2024IncompatiblePatInfo>,
79
80    /// Stores the types which were implicitly dereferenced in pattern binding modes
81    /// for later usage in THIR lowering. For example,
82    ///
83    /// ```
84    /// match &&Some(5i32) {
85    ///     Some(n) => {},
86    ///     _ => {},
87    /// }
88    /// ```
89    /// leads to a `vec![&&Option<i32>, &Option<i32>]`. Empty vectors are not stored.
90    ///
91    /// See:
92    /// <https://github.com/rust-lang/rfcs/blob/master/text/2005-match-ergonomics.md#definitions>
93    pat_adjustments: ItemLocalMap<Vec<Ty<'tcx>>>,
94
95    /// Set of reference patterns that match against a match-ergonomics inserted reference
96    /// (as opposed to against a reference in the scrutinee type).
97    skipped_ref_pats: ItemLocalSet,
98
99    /// Records the reasons that we picked the kind of each closure;
100    /// not all closures are present in the map.
101    closure_kind_origins: ItemLocalMap<(Span, HirPlace<'tcx>)>,
102
103    /// For each fn, records the "liberated" types of its arguments
104    /// and return type. Liberated means that all bound regions
105    /// (including late-bound regions) are replaced with free
106    /// equivalents. This table is not used in codegen (since regions
107    /// are erased there) and hence is not serialized to metadata.
108    ///
109    /// This table also contains the "revealed" values for any `impl Trait`
110    /// that appear in the signature and whose values are being inferred
111    /// by this function.
112    ///
113    /// # Example
114    ///
115    /// ```rust
116    /// # use std::fmt::Debug;
117    /// fn foo(x: &u32) -> impl Debug { *x }
118    /// ```
119    ///
120    /// The function signature here would be:
121    ///
122    /// ```ignore (illustrative)
123    /// for<'a> fn(&'a u32) -> Foo
124    /// ```
125    ///
126    /// where `Foo` is an opaque type created for this function.
127    ///
128    ///
129    /// The *liberated* form of this would be
130    ///
131    /// ```ignore (illustrative)
132    /// fn(&'a u32) -> u32
133    /// ```
134    ///
135    /// Note that `'a` is not bound (it would be an `ReLateParam`) and
136    /// that the `Foo` opaque type is replaced by its hidden type.
137    liberated_fn_sigs: ItemLocalMap<ty::FnSig<'tcx>>,
138
139    /// For each FRU expression, record the normalized types of the fields
140    /// of the struct - this is needed because it is non-trivial to
141    /// normalize while preserving regions. This table is used only in
142    /// MIR construction and hence is not serialized to metadata.
143    fru_field_types: ItemLocalMap<Vec<Ty<'tcx>>>,
144
145    /// For every coercion cast we add the HIR node ID of the cast
146    /// expression to this set.
147    coercion_casts: ItemLocalSet,
148
149    /// Set of trait imports actually used in the method resolution.
150    /// This is used for warning unused imports.
151    pub used_trait_imports: UnordSet<LocalDefId>,
152
153    /// If any errors occurred while type-checking this body,
154    /// this field will be set to `Some(ErrorGuaranteed)`.
155    pub tainted_by_errors: Option<ErrorGuaranteed>,
156
157    /// All the opaque types that have hidden types set by this function.
158    /// We also store the type here, so that the compiler can use it as a hint
159    /// for figuring out hidden types, even if they are only set in dead code
160    /// (which doesn't show up in MIR).
161    pub concrete_opaque_types: FxIndexMap<ty::OpaqueTypeKey<'tcx>, ty::OpaqueHiddenType<'tcx>>,
162
163    /// Tracks the minimum captures required for a closure;
164    /// see `MinCaptureInformationMap` for more details.
165    pub closure_min_captures: ty::MinCaptureInformationMap<'tcx>,
166
167    /// Tracks the fake reads required for a closure and the reason for the fake read.
168    /// When performing pattern matching for closures, there are times we don't end up
169    /// reading places that are mentioned in a closure (because of _ patterns). However,
170    /// to ensure the places are initialized, we introduce fake reads.
171    /// Consider these two examples:
172    /// ```ignore (discriminant matching with only wildcard arm)
173    /// let x: u8;
174    /// let c = || match x { _ => () };
175    /// ```
176    /// In this example, we don't need to actually read/borrow `x` in `c`, and so we don't
177    /// want to capture it. However, we do still want an error here, because `x` should have
178    /// to be initialized at the point where c is created. Therefore, we add a "fake read"
179    /// instead.
180    /// ```ignore (destructured assignments)
181    /// let c = || {
182    ///     let (t1, t2) = t;
183    /// }
184    /// ```
185    /// In the second example, we capture the disjoint fields of `t` (`t.0` & `t.1`), but
186    /// we never capture `t`. This becomes an issue when we build MIR as we require
187    /// information on `t` in order to create place `t.0` and `t.1`. We can solve this
188    /// issue by fake reading `t`.
189    pub closure_fake_reads: LocalDefIdMap<Vec<(HirPlace<'tcx>, FakeReadCause, HirId)>>,
190
191    /// Tracks the rvalue scoping rules which defines finer scoping for rvalue expressions
192    /// by applying extended parameter rules.
193    /// Details may be find in `rustc_hir_analysis::check::rvalue_scopes`.
194    pub rvalue_scopes: RvalueScopes,
195
196    /// Stores the predicates that apply on coroutine witness types.
197    /// formatting modified file tests/ui/coroutine/retain-resume-ref.rs
198    pub coroutine_stalled_predicates: FxIndexSet<(ty::Predicate<'tcx>, ObligationCause<'tcx>)>,
199
200    /// We sometimes treat byte string literals (which are of type `&[u8; N]`)
201    /// as `&[u8]`, depending on the pattern in which they are used.
202    /// This hashset records all instances where we behave
203    /// like this to allow `const_to_pat` to reliably handle this situation.
204    pub treat_byte_string_as_slice: ItemLocalSet,
205
206    /// Contains the data for evaluating the effect of feature `capture_disjoint_fields`
207    /// on closure size.
208    pub closure_size_eval: LocalDefIdMap<ClosureSizeProfileData<'tcx>>,
209
210    /// Container types and field indices of `offset_of!` expressions
211    offset_of_data: ItemLocalMap<(Ty<'tcx>, Vec<(VariantIdx, FieldIdx)>)>,
212}
213
214impl<'tcx> TypeckResults<'tcx> {
215    pub fn new(hir_owner: OwnerId) -> TypeckResults<'tcx> {
216        TypeckResults {
217            hir_owner,
218            type_dependent_defs: Default::default(),
219            field_indices: Default::default(),
220            user_provided_types: Default::default(),
221            user_provided_sigs: Default::default(),
222            node_types: Default::default(),
223            node_args: Default::default(),
224            adjustments: Default::default(),
225            pat_binding_modes: Default::default(),
226            pat_adjustments: Default::default(),
227            rust_2024_migration_desugared_pats: Default::default(),
228            skipped_ref_pats: Default::default(),
229            closure_kind_origins: Default::default(),
230            liberated_fn_sigs: Default::default(),
231            fru_field_types: Default::default(),
232            coercion_casts: Default::default(),
233            used_trait_imports: Default::default(),
234            tainted_by_errors: None,
235            concrete_opaque_types: Default::default(),
236            closure_min_captures: Default::default(),
237            closure_fake_reads: Default::default(),
238            rvalue_scopes: Default::default(),
239            coroutine_stalled_predicates: Default::default(),
240            treat_byte_string_as_slice: Default::default(),
241            closure_size_eval: Default::default(),
242            offset_of_data: Default::default(),
243        }
244    }
245
246    /// Returns the final resolution of a `QPath` in an `Expr` or `Pat` node.
247    pub fn qpath_res(&self, qpath: &hir::QPath<'_>, id: HirId) -> Res {
248        match *qpath {
249            hir::QPath::Resolved(_, path) => path.res,
250            hir::QPath::TypeRelative(..) | hir::QPath::LangItem(..) => self
251                .type_dependent_def(id)
252                .map_or(Res::Err, |(kind, def_id)| Res::Def(kind, def_id)),
253        }
254    }
255
256    pub fn type_dependent_defs(
257        &self,
258    ) -> LocalTableInContext<'_, Result<(DefKind, DefId), ErrorGuaranteed>> {
259        LocalTableInContext { hir_owner: self.hir_owner, data: &self.type_dependent_defs }
260    }
261
262    pub fn type_dependent_def(&self, id: HirId) -> Option<(DefKind, DefId)> {
263        validate_hir_id_for_typeck_results(self.hir_owner, id);
264        self.type_dependent_defs.get(&id.local_id).cloned().and_then(|r| r.ok())
265    }
266
267    pub fn type_dependent_def_id(&self, id: HirId) -> Option<DefId> {
268        self.type_dependent_def(id).map(|(_, def_id)| def_id)
269    }
270
271    pub fn type_dependent_defs_mut(
272        &mut self,
273    ) -> LocalTableInContextMut<'_, Result<(DefKind, DefId), ErrorGuaranteed>> {
274        LocalTableInContextMut { hir_owner: self.hir_owner, data: &mut self.type_dependent_defs }
275    }
276
277    pub fn field_indices(&self) -> LocalTableInContext<'_, FieldIdx> {
278        LocalTableInContext { hir_owner: self.hir_owner, data: &self.field_indices }
279    }
280
281    pub fn field_indices_mut(&mut self) -> LocalTableInContextMut<'_, FieldIdx> {
282        LocalTableInContextMut { hir_owner: self.hir_owner, data: &mut self.field_indices }
283    }
284
285    pub fn field_index(&self, id: HirId) -> FieldIdx {
286        self.field_indices().get(id).cloned().expect("no index for a field")
287    }
288
289    pub fn opt_field_index(&self, id: HirId) -> Option<FieldIdx> {
290        self.field_indices().get(id).cloned()
291    }
292
293    pub fn user_provided_types(&self) -> LocalTableInContext<'_, CanonicalUserType<'tcx>> {
294        LocalTableInContext { hir_owner: self.hir_owner, data: &self.user_provided_types }
295    }
296
297    pub fn user_provided_types_mut(
298        &mut self,
299    ) -> LocalTableInContextMut<'_, CanonicalUserType<'tcx>> {
300        LocalTableInContextMut { hir_owner: self.hir_owner, data: &mut self.user_provided_types }
301    }
302
303    pub fn node_types(&self) -> LocalTableInContext<'_, Ty<'tcx>> {
304        LocalTableInContext { hir_owner: self.hir_owner, data: &self.node_types }
305    }
306
307    pub fn node_types_mut(&mut self) -> LocalTableInContextMut<'_, Ty<'tcx>> {
308        LocalTableInContextMut { hir_owner: self.hir_owner, data: &mut self.node_types }
309    }
310
311    pub fn node_type(&self, id: HirId) -> Ty<'tcx> {
312        self.node_type_opt(id).unwrap_or_else(|| {
313            bug!("node_type: no type for node {}", tls::with(|tcx| tcx.hir_id_to_string(id)))
314        })
315    }
316
317    pub fn node_type_opt(&self, id: HirId) -> Option<Ty<'tcx>> {
318        validate_hir_id_for_typeck_results(self.hir_owner, id);
319        self.node_types.get(&id.local_id).cloned()
320    }
321
322    pub fn node_args_mut(&mut self) -> LocalTableInContextMut<'_, GenericArgsRef<'tcx>> {
323        LocalTableInContextMut { hir_owner: self.hir_owner, data: &mut self.node_args }
324    }
325
326    pub fn node_args(&self, id: HirId) -> GenericArgsRef<'tcx> {
327        validate_hir_id_for_typeck_results(self.hir_owner, id);
328        self.node_args.get(&id.local_id).cloned().unwrap_or_else(|| GenericArgs::empty())
329    }
330
331    pub fn node_args_opt(&self, id: HirId) -> Option<GenericArgsRef<'tcx>> {
332        validate_hir_id_for_typeck_results(self.hir_owner, id);
333        self.node_args.get(&id.local_id).cloned()
334    }
335
336    /// Returns the type of a pattern as a monotype. Like [`expr_ty`], this function
337    /// doesn't provide type parameter args.
338    ///
339    /// [`expr_ty`]: TypeckResults::expr_ty
340    pub fn pat_ty(&self, pat: &hir::Pat<'_>) -> Ty<'tcx> {
341        self.node_type(pat.hir_id)
342    }
343
344    /// Returns the type of an expression as a monotype.
345    ///
346    /// NB (1): This is the PRE-ADJUSTMENT TYPE for the expression. That is, in
347    /// some cases, we insert `Adjustment` annotations such as auto-deref or
348    /// auto-ref. The type returned by this function does not consider such
349    /// adjustments. See [`Self::expr_ty_adjusted`] instead.
350    ///
351    /// NB (2): This type doesn't provide type parameter args; e.g., if you
352    /// ask for the type of `id` in `id(3)`, it will return `fn(&isize) -> isize`
353    /// instead of `fn(ty) -> T with T = isize`.
354    pub fn expr_ty(&self, expr: &hir::Expr<'_>) -> Ty<'tcx> {
355        self.node_type(expr.hir_id)
356    }
357
358    pub fn expr_ty_opt(&self, expr: &hir::Expr<'_>) -> Option<Ty<'tcx>> {
359        self.node_type_opt(expr.hir_id)
360    }
361
362    pub fn adjustments(&self) -> LocalTableInContext<'_, Vec<ty::adjustment::Adjustment<'tcx>>> {
363        LocalTableInContext { hir_owner: self.hir_owner, data: &self.adjustments }
364    }
365
366    pub fn adjustments_mut(
367        &mut self,
368    ) -> LocalTableInContextMut<'_, Vec<ty::adjustment::Adjustment<'tcx>>> {
369        LocalTableInContextMut { hir_owner: self.hir_owner, data: &mut self.adjustments }
370    }
371
372    pub fn expr_adjustments(&self, expr: &hir::Expr<'_>) -> &[ty::adjustment::Adjustment<'tcx>] {
373        validate_hir_id_for_typeck_results(self.hir_owner, expr.hir_id);
374        self.adjustments.get(&expr.hir_id.local_id).map_or(&[], |a| &a[..])
375    }
376
377    /// Returns the type of `expr`, considering any `Adjustment`
378    /// entry recorded for that expression.
379    pub fn expr_ty_adjusted(&self, expr: &hir::Expr<'_>) -> Ty<'tcx> {
380        self.expr_adjustments(expr).last().map_or_else(|| self.expr_ty(expr), |adj| adj.target)
381    }
382
383    pub fn expr_ty_adjusted_opt(&self, expr: &hir::Expr<'_>) -> Option<Ty<'tcx>> {
384        self.expr_adjustments(expr).last().map(|adj| adj.target).or_else(|| self.expr_ty_opt(expr))
385    }
386
387    pub fn is_method_call(&self, expr: &hir::Expr<'_>) -> bool {
388        // Only paths and method calls/overloaded operators have
389        // entries in type_dependent_defs, ignore the former here.
390        if let hir::ExprKind::Path(_) = expr.kind {
391            return false;
392        }
393
394        matches!(self.type_dependent_defs().get(expr.hir_id), Some(Ok((DefKind::AssocFn, _))))
395    }
396
397    /// Returns the computed binding mode for a `PatKind::Binding` pattern
398    /// (after match ergonomics adjustments).
399    pub fn extract_binding_mode(&self, s: &Session, id: HirId, sp: Span) -> BindingMode {
400        self.pat_binding_modes().get(id).copied().unwrap_or_else(|| {
401            s.dcx().span_bug(sp, "missing binding mode");
402        })
403    }
404
405    pub fn pat_binding_modes(&self) -> LocalTableInContext<'_, BindingMode> {
406        LocalTableInContext { hir_owner: self.hir_owner, data: &self.pat_binding_modes }
407    }
408
409    pub fn pat_binding_modes_mut(&mut self) -> LocalTableInContextMut<'_, BindingMode> {
410        LocalTableInContextMut { hir_owner: self.hir_owner, data: &mut self.pat_binding_modes }
411    }
412
413    pub fn pat_adjustments(&self) -> LocalTableInContext<'_, Vec<Ty<'tcx>>> {
414        LocalTableInContext { hir_owner: self.hir_owner, data: &self.pat_adjustments }
415    }
416
417    pub fn pat_adjustments_mut(&mut self) -> LocalTableInContextMut<'_, Vec<Ty<'tcx>>> {
418        LocalTableInContextMut { hir_owner: self.hir_owner, data: &mut self.pat_adjustments }
419    }
420
421    pub fn rust_2024_migration_desugared_pats(
422        &self,
423    ) -> LocalTableInContext<'_, Rust2024IncompatiblePatInfo> {
424        LocalTableInContext {
425            hir_owner: self.hir_owner,
426            data: &self.rust_2024_migration_desugared_pats,
427        }
428    }
429
430    pub fn rust_2024_migration_desugared_pats_mut(
431        &mut self,
432    ) -> LocalTableInContextMut<'_, Rust2024IncompatiblePatInfo> {
433        LocalTableInContextMut {
434            hir_owner: self.hir_owner,
435            data: &mut self.rust_2024_migration_desugared_pats,
436        }
437    }
438
439    pub fn skipped_ref_pats(&self) -> LocalSetInContext<'_> {
440        LocalSetInContext { hir_owner: self.hir_owner, data: &self.skipped_ref_pats }
441    }
442
443    pub fn skipped_ref_pats_mut(&mut self) -> LocalSetInContextMut<'_> {
444        LocalSetInContextMut { hir_owner: self.hir_owner, data: &mut self.skipped_ref_pats }
445    }
446
447    /// Does the pattern recursively contain a `ref mut` binding in it?
448    ///
449    /// This is used to determined whether a `deref` pattern should emit a `Deref`
450    /// or `DerefMut` call for its pattern scrutinee.
451    ///
452    /// This is computed from the typeck results since we want to make
453    /// sure to apply any match-ergonomics adjustments, which we cannot
454    /// determine from the HIR alone.
455    pub fn pat_has_ref_mut_binding(&self, pat: &hir::Pat<'_>) -> bool {
456        let mut has_ref_mut = false;
457        pat.walk(|pat| {
458            if let hir::PatKind::Binding(_, id, _, _) = pat.kind
459                && let Some(BindingMode(ByRef::Yes(Mutability::Mut), _)) =
460                    self.pat_binding_modes().get(id)
461            {
462                has_ref_mut = true;
463                // No need to continue recursing
464                false
465            } else {
466                true
467            }
468        });
469        has_ref_mut
470    }
471
472    /// For a given closure, returns the iterator of `ty::CapturedPlace`s that are captured
473    /// by the closure.
474    pub fn closure_min_captures_flattened(
475        &self,
476        closure_def_id: LocalDefId,
477    ) -> impl Iterator<Item = &ty::CapturedPlace<'tcx>> {
478        self.closure_min_captures
479            .get(&closure_def_id)
480            .map(|closure_min_captures| closure_min_captures.values().flat_map(|v| v.iter()))
481            .into_iter()
482            .flatten()
483    }
484
485    pub fn closure_kind_origins(&self) -> LocalTableInContext<'_, (Span, HirPlace<'tcx>)> {
486        LocalTableInContext { hir_owner: self.hir_owner, data: &self.closure_kind_origins }
487    }
488
489    pub fn closure_kind_origins_mut(
490        &mut self,
491    ) -> LocalTableInContextMut<'_, (Span, HirPlace<'tcx>)> {
492        LocalTableInContextMut { hir_owner: self.hir_owner, data: &mut self.closure_kind_origins }
493    }
494
495    pub fn liberated_fn_sigs(&self) -> LocalTableInContext<'_, ty::FnSig<'tcx>> {
496        LocalTableInContext { hir_owner: self.hir_owner, data: &self.liberated_fn_sigs }
497    }
498
499    pub fn liberated_fn_sigs_mut(&mut self) -> LocalTableInContextMut<'_, ty::FnSig<'tcx>> {
500        LocalTableInContextMut { hir_owner: self.hir_owner, data: &mut self.liberated_fn_sigs }
501    }
502
503    pub fn fru_field_types(&self) -> LocalTableInContext<'_, Vec<Ty<'tcx>>> {
504        LocalTableInContext { hir_owner: self.hir_owner, data: &self.fru_field_types }
505    }
506
507    pub fn fru_field_types_mut(&mut self) -> LocalTableInContextMut<'_, Vec<Ty<'tcx>>> {
508        LocalTableInContextMut { hir_owner: self.hir_owner, data: &mut self.fru_field_types }
509    }
510
511    pub fn is_coercion_cast(&self, hir_id: HirId) -> bool {
512        validate_hir_id_for_typeck_results(self.hir_owner, hir_id);
513        self.coercion_casts.contains(&hir_id.local_id)
514    }
515
516    pub fn set_coercion_cast(&mut self, id: ItemLocalId) {
517        self.coercion_casts.insert(id);
518    }
519
520    pub fn coercion_casts(&self) -> &ItemLocalSet {
521        &self.coercion_casts
522    }
523
524    pub fn offset_of_data(
525        &self,
526    ) -> LocalTableInContext<'_, (Ty<'tcx>, Vec<(VariantIdx, FieldIdx)>)> {
527        LocalTableInContext { hir_owner: self.hir_owner, data: &self.offset_of_data }
528    }
529
530    pub fn offset_of_data_mut(
531        &mut self,
532    ) -> LocalTableInContextMut<'_, (Ty<'tcx>, Vec<(VariantIdx, FieldIdx)>)> {
533        LocalTableInContextMut { hir_owner: self.hir_owner, data: &mut self.offset_of_data }
534    }
535}
536
537/// Validate that the given HirId (respectively its `local_id` part) can be
538/// safely used as a key in the maps of a TypeckResults. For that to be
539/// the case, the HirId must have the same `owner` as all the other IDs in
540/// this table (signified by `hir_owner`). Otherwise the HirId
541/// would be in a different frame of reference and using its `local_id`
542/// would result in lookup errors, or worse, in silently wrong data being
543/// stored/returned.
544#[inline]
545fn validate_hir_id_for_typeck_results(hir_owner: OwnerId, hir_id: HirId) {
546    if hir_id.owner != hir_owner {
547        invalid_hir_id_for_typeck_results(hir_owner, hir_id);
548    }
549}
550
551#[cold]
552#[inline(never)]
553fn invalid_hir_id_for_typeck_results(hir_owner: OwnerId, hir_id: HirId) {
554    ty::tls::with(|tcx| {
555        bug!(
556            "node {} cannot be placed in TypeckResults with hir_owner {:?}",
557            tcx.hir_id_to_string(hir_id),
558            hir_owner
559        )
560    });
561}
562
563pub struct LocalTableInContext<'a, V> {
564    hir_owner: OwnerId,
565    data: &'a ItemLocalMap<V>,
566}
567
568impl<'a, V> LocalTableInContext<'a, V> {
569    pub fn contains_key(&self, id: HirId) -> bool {
570        validate_hir_id_for_typeck_results(self.hir_owner, id);
571        self.data.contains_key(&id.local_id)
572    }
573
574    pub fn get(&self, id: HirId) -> Option<&'a V> {
575        validate_hir_id_for_typeck_results(self.hir_owner, id);
576        self.data.get(&id.local_id)
577    }
578
579    pub fn items(
580        &self,
581    ) -> UnordItems<(hir::ItemLocalId, &'a V), impl Iterator<Item = (hir::ItemLocalId, &'a V)>>
582    {
583        self.data.items().map(|(id, value)| (*id, value))
584    }
585
586    pub fn items_in_stable_order(&self) -> Vec<(ItemLocalId, &'a V)> {
587        self.data.items().map(|(&k, v)| (k, v)).into_sorted_stable_ord_by_key(|(k, _)| k)
588    }
589}
590
591impl<'a, V> ::std::ops::Index<HirId> for LocalTableInContext<'a, V> {
592    type Output = V;
593
594    fn index(&self, key: HirId) -> &V {
595        self.get(key).unwrap_or_else(|| {
596            bug!("LocalTableInContext({:?}): key {:?} not found", self.hir_owner, key)
597        })
598    }
599}
600
601pub struct LocalTableInContextMut<'a, V> {
602    hir_owner: OwnerId,
603    data: &'a mut ItemLocalMap<V>,
604}
605
606impl<'a, V> LocalTableInContextMut<'a, V> {
607    pub fn get_mut(&mut self, id: HirId) -> Option<&mut V> {
608        validate_hir_id_for_typeck_results(self.hir_owner, id);
609        self.data.get_mut(&id.local_id)
610    }
611
612    pub fn get(&mut self, id: HirId) -> Option<&V> {
613        validate_hir_id_for_typeck_results(self.hir_owner, id);
614        self.data.get(&id.local_id)
615    }
616
617    pub fn entry(&mut self, id: HirId) -> Entry<'_, hir::ItemLocalId, V> {
618        validate_hir_id_for_typeck_results(self.hir_owner, id);
619        self.data.entry(id.local_id)
620    }
621
622    pub fn insert(&mut self, id: HirId, val: V) -> Option<V> {
623        validate_hir_id_for_typeck_results(self.hir_owner, id);
624        self.data.insert(id.local_id, val)
625    }
626
627    pub fn remove(&mut self, id: HirId) -> Option<V> {
628        validate_hir_id_for_typeck_results(self.hir_owner, id);
629        self.data.remove(&id.local_id)
630    }
631
632    pub fn extend(&mut self, items: UnordItems<(HirId, V), impl Iterator<Item = (HirId, V)>>) {
633        self.data.extend_unord(items.map(|(id, value)| {
634            validate_hir_id_for_typeck_results(self.hir_owner, id);
635            (id.local_id, value)
636        }))
637    }
638}
639
640#[derive(Clone, Copy, Debug)]
641pub struct LocalSetInContext<'a> {
642    hir_owner: OwnerId,
643    data: &'a ItemLocalSet,
644}
645
646impl<'a> LocalSetInContext<'a> {
647    pub fn is_empty(&self) -> bool {
648        self.data.is_empty()
649    }
650
651    pub fn contains(&self, id: hir::HirId) -> bool {
652        validate_hir_id_for_typeck_results(self.hir_owner, id);
653        self.data.contains(&id.local_id)
654    }
655}
656
657#[derive(Debug)]
658pub struct LocalSetInContextMut<'a> {
659    hir_owner: OwnerId,
660    data: &'a mut ItemLocalSet,
661}
662
663impl<'a> LocalSetInContextMut<'a> {
664    pub fn is_empty(&self) -> bool {
665        self.data.is_empty()
666    }
667
668    pub fn contains(&self, id: hir::HirId) -> bool {
669        validate_hir_id_for_typeck_results(self.hir_owner, id);
670        self.data.contains(&id.local_id)
671    }
672    pub fn insert(&mut self, id: hir::HirId) -> bool {
673        validate_hir_id_for_typeck_results(self.hir_owner, id);
674        self.data.insert(id.local_id)
675    }
676
677    pub fn remove(&mut self, id: hir::HirId) -> bool {
678        validate_hir_id_for_typeck_results(self.hir_owner, id);
679        self.data.remove(&id.local_id)
680    }
681}
682
683rustc_index::newtype_index! {
684    #[derive(HashStable)]
685    #[encodable]
686    #[debug_format = "UserType({})"]
687    pub struct UserTypeAnnotationIndex {
688        const START_INDEX = 0;
689    }
690}
691
692/// Mapping of type annotation indices to canonical user type annotations.
693pub type CanonicalUserTypeAnnotations<'tcx> =
694    IndexVec<UserTypeAnnotationIndex, CanonicalUserTypeAnnotation<'tcx>>;
695
696#[derive(Clone, Debug, TyEncodable, TyDecodable, HashStable, TypeFoldable, TypeVisitable)]
697pub struct CanonicalUserTypeAnnotation<'tcx> {
698    pub user_ty: Box<CanonicalUserType<'tcx>>,
699    pub span: Span,
700    pub inferred_ty: Ty<'tcx>,
701}
702
703/// Canonical user type annotation.
704pub type CanonicalUserType<'tcx> = Canonical<'tcx, UserType<'tcx>>;
705
706#[derive(Copy, Clone, Debug, PartialEq, TyEncodable, TyDecodable)]
707#[derive(Eq, Hash, HashStable, TypeFoldable, TypeVisitable)]
708pub struct UserType<'tcx> {
709    pub kind: UserTypeKind<'tcx>,
710    pub bounds: ty::Clauses<'tcx>,
711}
712
713impl<'tcx> UserType<'tcx> {
714    pub fn new(kind: UserTypeKind<'tcx>) -> UserType<'tcx> {
715        UserType { kind, bounds: ty::ListWithCachedTypeInfo::empty() }
716    }
717
718    /// A user type annotation with additional bounds that need to be enforced.
719    /// These bounds are lowered from `impl Trait` in bindings.
720    pub fn new_with_bounds(kind: UserTypeKind<'tcx>, bounds: ty::Clauses<'tcx>) -> UserType<'tcx> {
721        UserType { kind, bounds }
722    }
723}
724
725/// A user-given type annotation attached to a constant. These arise
726/// from constants that are named via paths, like `Foo::<A>::new` and
727/// so forth.
728#[derive(Copy, Clone, Debug, PartialEq, TyEncodable, TyDecodable)]
729#[derive(Eq, Hash, HashStable, TypeFoldable, TypeVisitable)]
730pub enum UserTypeKind<'tcx> {
731    Ty(Ty<'tcx>),
732
733    /// The canonical type is the result of `type_of(def_id)` with the
734    /// given generic parameters applied.
735    TypeOf(DefId, UserArgs<'tcx>),
736}
737
738pub trait IsIdentity {
739    fn is_identity(&self) -> bool;
740}
741
742impl<'tcx> IsIdentity for CanonicalUserType<'tcx> {
743    /// Returns `true` if this represents the generic parameters of the form `[?0, ?1, ?2]`,
744    /// i.e., each thing is mapped to a canonical variable with the same index.
745    fn is_identity(&self) -> bool {
746        if !self.value.bounds.is_empty() {
747            return false;
748        }
749
750        match self.value.kind {
751            UserTypeKind::Ty(_) => false,
752            UserTypeKind::TypeOf(_, user_args) => {
753                if user_args.user_self_ty.is_some() {
754                    return false;
755                }
756
757                iter::zip(user_args.args, BoundVar::ZERO..).all(|(kind, cvar)| {
758                    match kind.unpack() {
759                        GenericArgKind::Type(ty) => match ty.kind() {
760                            ty::Bound(debruijn, b) => {
761                                // We only allow a `ty::INNERMOST` index in generic parameters.
762                                assert_eq!(*debruijn, ty::INNERMOST);
763                                cvar == b.var
764                            }
765                            _ => false,
766                        },
767
768                        GenericArgKind::Lifetime(r) => match *r {
769                            ty::ReBound(debruijn, br) => {
770                                // We only allow a `ty::INNERMOST` index in generic parameters.
771                                assert_eq!(debruijn, ty::INNERMOST);
772                                cvar == br.var
773                            }
774                            _ => false,
775                        },
776
777                        GenericArgKind::Const(ct) => match ct.kind() {
778                            ty::ConstKind::Bound(debruijn, b) => {
779                                // We only allow a `ty::INNERMOST` index in generic parameters.
780                                assert_eq!(debruijn, ty::INNERMOST);
781                                cvar == b
782                            }
783                            _ => false,
784                        },
785                    }
786                })
787            }
788        }
789    }
790}
791
792impl<'tcx> std::fmt::Display for UserType<'tcx> {
793    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
794        if self.bounds.is_empty() {
795            self.kind.fmt(f)
796        } else {
797            self.kind.fmt(f)?;
798            write!(f, " + ")?;
799            std::fmt::Debug::fmt(&self.bounds, f)
800        }
801    }
802}
803
804impl<'tcx> std::fmt::Display for UserTypeKind<'tcx> {
805    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
806        match self {
807            Self::Ty(arg0) => {
808                ty::print::with_no_trimmed_paths!(write!(f, "Ty({})", arg0))
809            }
810            Self::TypeOf(arg0, arg1) => write!(f, "TypeOf({:?}, {:?})", arg0, arg1),
811        }
812    }
813}
814
815/// Information on a pattern incompatible with Rust 2024, for use by the error/migration diagnostic
816/// emitted during THIR construction.
817#[derive(TyEncodable, TyDecodable, Debug, HashStable)]
818pub struct Rust2024IncompatiblePatInfo {
819    /// Labeled spans for `&`s, `&mut`s, and binding modifiers incompatible with Rust 2024.
820    pub primary_labels: Vec<(Span, String)>,
821    /// Whether any binding modifiers occur under a non-`move` default binding mode.
822    pub bad_modifiers: bool,
823    /// Whether any `&` or `&mut` patterns occur under a non-`move` default binding mode.
824    pub bad_ref_pats: bool,
825    /// If `true`, we can give a simpler suggestion solely by eliding explicit binding modifiers.
826    pub suggest_eliding_modes: bool,
827}
rustc_middle/ty/typeck_results.rs

rustc_middle/ty/
typeck_results.rs
