rustc_type_ir/
interner.rs

1use std::fmt::Debug;
2use std::hash::Hash;
3use std::ops::Deref;
4
5use rustc_ast_ir::Movability;
6use rustc_index::bit_set::DenseBitSet;
7use smallvec::SmallVec;
8
9use crate::fold::TypeFoldable;
10use crate::inherent::*;
11use crate::ir_print::IrPrint;
12use crate::lang_items::TraitSolverLangItem;
13use crate::relate::Relate;
14use crate::solve::{CanonicalInput, ExternalConstraintsData, PredefinedOpaquesData, QueryResult};
15use crate::visit::{Flags, TypeSuperVisitable, TypeVisitable};
16use crate::{self as ty, search_graph};
17
18#[cfg_attr(feature = "nightly", rustc_diagnostic_item = "type_ir_interner")]
19pub trait Interner:
20    Sized
21    + Copy
22    + IrPrint<ty::AliasTy<Self>>
23    + IrPrint<ty::AliasTerm<Self>>
24    + IrPrint<ty::TraitRef<Self>>
25    + IrPrint<ty::TraitPredicate<Self>>
26    + IrPrint<ty::HostEffectPredicate<Self>>
27    + IrPrint<ty::ExistentialTraitRef<Self>>
28    + IrPrint<ty::ExistentialProjection<Self>>
29    + IrPrint<ty::ProjectionPredicate<Self>>
30    + IrPrint<ty::NormalizesTo<Self>>
31    + IrPrint<ty::SubtypePredicate<Self>>
32    + IrPrint<ty::CoercePredicate<Self>>
33    + IrPrint<ty::FnSig<Self>>
34    + IrPrint<ty::PatternKind<Self>>
35{
36    type DefId: DefId<Self>;
37    type LocalDefId: Copy + Debug + Hash + Eq + Into<Self::DefId> + TypeFoldable<Self>;
38    type Span: Span<Self>;
39
40    type GenericArgs: GenericArgs<Self>;
41    type GenericArgsSlice: Copy + Debug + Hash + Eq + SliceLike<Item = Self::GenericArg>;
42    type GenericArg: GenericArg<Self>;
43    type Term: Term<Self>;
44
45    type BoundVarKinds: Copy + Debug + Hash + Eq + SliceLike<Item = Self::BoundVarKind> + Default;
46    type BoundVarKind: Copy + Debug + Hash + Eq;
47
48    type PredefinedOpaques: Copy
49        + Debug
50        + Hash
51        + Eq
52        + TypeFoldable<Self>
53        + Deref<Target = PredefinedOpaquesData<Self>>;
54    fn mk_predefined_opaques_in_body(
55        self,
56        data: PredefinedOpaquesData<Self>,
57    ) -> Self::PredefinedOpaques;
58
59    type LocalDefIds: Copy
60        + Debug
61        + Hash
62        + Default
63        + Eq
64        + TypeVisitable<Self>
65        + SliceLike<Item = Self::LocalDefId>;
66
67    type CanonicalVars: Copy
68        + Debug
69        + Hash
70        + Eq
71        + SliceLike<Item = ty::CanonicalVarInfo<Self>>
72        + Default;
73    fn mk_canonical_var_infos(self, infos: &[ty::CanonicalVarInfo<Self>]) -> Self::CanonicalVars;
74
75    type ExternalConstraints: Copy
76        + Debug
77        + Hash
78        + Eq
79        + TypeFoldable<Self>
80        + Deref<Target = ExternalConstraintsData<Self>>;
81    fn mk_external_constraints(
82        self,
83        data: ExternalConstraintsData<Self>,
84    ) -> Self::ExternalConstraints;
85
86    type DepNodeIndex;
87    type Tracked<T: Debug + Clone>: Debug;
88    fn mk_tracked<T: Debug + Clone>(
89        self,
90        data: T,
91        dep_node: Self::DepNodeIndex,
92    ) -> Self::Tracked<T>;
93    fn get_tracked<T: Debug + Clone>(self, tracked: &Self::Tracked<T>) -> T;
94    fn with_cached_task<T>(self, task: impl FnOnce() -> T) -> (T, Self::DepNodeIndex);
95
96    // Kinds of tys
97    type Ty: Ty<Self>;
98    type Tys: Tys<Self>;
99    type FnInputTys: Copy + Debug + Hash + Eq + SliceLike<Item = Self::Ty> + TypeVisitable<Self>;
100    type ParamTy: Copy + Debug + Hash + Eq + ParamLike;
101    type BoundTy: Copy + Debug + Hash + Eq + BoundVarLike<Self>;
102    type PlaceholderTy: PlaceholderLike;
103
104    // Things stored inside of tys
105    type ErrorGuaranteed: Copy + Debug + Hash + Eq;
106    type BoundExistentialPredicates: BoundExistentialPredicates<Self>;
107    type AllocId: Copy + Debug + Hash + Eq;
108    type Pat: Copy
109        + Debug
110        + Hash
111        + Eq
112        + Debug
113        + Relate<Self>
114        + Flags
115        + IntoKind<Kind = ty::PatternKind<Self>>;
116    type PatList: Copy
117        + Debug
118        + Hash
119        + Default
120        + Eq
121        + TypeVisitable<Self>
122        + SliceLike<Item = Self::Pat>;
123    type Safety: Safety<Self>;
124    type Abi: Abi<Self>;
125
126    // Kinds of consts
127    type Const: Const<Self>;
128    type PlaceholderConst: PlaceholderLike;
129    type ParamConst: Copy + Debug + Hash + Eq + ParamLike;
130    type BoundConst: Copy + Debug + Hash + Eq + BoundVarLike<Self>;
131    type ValueConst: ValueConst<Self>;
132    type ExprConst: ExprConst<Self>;
133    type ValTree: Copy + Debug + Hash + Eq;
134
135    // Kinds of regions
136    type Region: Region<Self>;
137    type EarlyParamRegion: Copy + Debug + Hash + Eq + ParamLike;
138    type LateParamRegion: Copy + Debug + Hash + Eq;
139    type BoundRegion: Copy + Debug + Hash + Eq + BoundVarLike<Self>;
140    type PlaceholderRegion: PlaceholderLike;
141
142    // Predicates
143    type ParamEnv: ParamEnv<Self>;
144    type Predicate: Predicate<Self>;
145    type Clause: Clause<Self>;
146    type Clauses: Copy + Debug + Hash + Eq + TypeSuperVisitable<Self> + Flags;
147
148    fn with_global_cache<R>(self, f: impl FnOnce(&mut search_graph::GlobalCache<Self>) -> R) -> R;
149
150    fn evaluation_is_concurrent(&self) -> bool;
151
152    fn expand_abstract_consts<T: TypeFoldable<Self>>(self, t: T) -> T;
153
154    type GenericsOf: GenericsOf<Self>;
155    fn generics_of(self, def_id: Self::DefId) -> Self::GenericsOf;
156
157    type VariancesOf: Copy + Debug + SliceLike<Item = ty::Variance>;
158    fn variances_of(self, def_id: Self::DefId) -> Self::VariancesOf;
159
160    fn opt_alias_variances(
161        self,
162        kind: impl Into<ty::AliasTermKind>,
163        def_id: Self::DefId,
164    ) -> Option<Self::VariancesOf>;
165
166    fn type_of(self, def_id: Self::DefId) -> ty::EarlyBinder<Self, Self::Ty>;
167    fn type_of_opaque_hir_typeck(self, def_id: Self::LocalDefId)
168    -> ty::EarlyBinder<Self, Self::Ty>;
169
170    type AdtDef: AdtDef<Self>;
171    fn adt_def(self, adt_def_id: Self::DefId) -> Self::AdtDef;
172
173    fn alias_ty_kind(self, alias: ty::AliasTy<Self>) -> ty::AliasTyKind;
174
175    fn alias_term_kind(self, alias: ty::AliasTerm<Self>) -> ty::AliasTermKind;
176
177    fn trait_ref_and_own_args_for_alias(
178        self,
179        def_id: Self::DefId,
180        args: Self::GenericArgs,
181    ) -> (ty::TraitRef<Self>, Self::GenericArgsSlice);
182
183    fn mk_args(self, args: &[Self::GenericArg]) -> Self::GenericArgs;
184
185    fn mk_args_from_iter<I, T>(self, args: I) -> T::Output
186    where
187        I: Iterator<Item = T>,
188        T: CollectAndApply<Self::GenericArg, Self::GenericArgs>;
189
190    fn check_args_compatible(self, def_id: Self::DefId, args: Self::GenericArgs) -> bool;
191
192    fn debug_assert_args_compatible(self, def_id: Self::DefId, args: Self::GenericArgs);
193
194    /// Assert that the args from an `ExistentialTraitRef` or `ExistentialProjection`
195    /// are compatible with the `DefId`.
196    fn debug_assert_existential_args_compatible(self, def_id: Self::DefId, args: Self::GenericArgs);
197
198    fn mk_type_list_from_iter<I, T>(self, args: I) -> T::Output
199    where
200        I: Iterator<Item = T>,
201        T: CollectAndApply<Self::Ty, Self::Tys>;
202
203    fn parent(self, def_id: Self::DefId) -> Self::DefId;
204
205    fn recursion_limit(self) -> usize;
206
207    type Features: Features<Self>;
208    fn features(self) -> Self::Features;
209
210    fn coroutine_hidden_types(
211        self,
212        def_id: Self::DefId,
213    ) -> ty::EarlyBinder<Self, ty::Binder<Self, Self::Tys>>;
214
215    fn fn_sig(
216        self,
217        def_id: Self::DefId,
218    ) -> ty::EarlyBinder<Self, ty::Binder<Self, ty::FnSig<Self>>>;
219
220    fn coroutine_movability(self, def_id: Self::DefId) -> Movability;
221
222    fn coroutine_for_closure(self, def_id: Self::DefId) -> Self::DefId;
223
224    fn generics_require_sized_self(self, def_id: Self::DefId) -> bool;
225
226    fn item_bounds(
227        self,
228        def_id: Self::DefId,
229    ) -> ty::EarlyBinder<Self, impl IntoIterator<Item = Self::Clause>>;
230
231    fn item_self_bounds(
232        self,
233        def_id: Self::DefId,
234    ) -> ty::EarlyBinder<Self, impl IntoIterator<Item = Self::Clause>>;
235
236    fn item_non_self_bounds(
237        self,
238        def_id: Self::DefId,
239    ) -> ty::EarlyBinder<Self, impl IntoIterator<Item = Self::Clause>>;
240
241    fn predicates_of(
242        self,
243        def_id: Self::DefId,
244    ) -> ty::EarlyBinder<Self, impl IntoIterator<Item = Self::Clause>>;
245
246    fn own_predicates_of(
247        self,
248        def_id: Self::DefId,
249    ) -> ty::EarlyBinder<Self, impl IntoIterator<Item = Self::Clause>>;
250
251    fn explicit_super_predicates_of(
252        self,
253        def_id: Self::DefId,
254    ) -> ty::EarlyBinder<Self, impl IntoIterator<Item = (Self::Clause, Self::Span)>>;
255
256    fn explicit_implied_predicates_of(
257        self,
258        def_id: Self::DefId,
259    ) -> ty::EarlyBinder<Self, impl IntoIterator<Item = (Self::Clause, Self::Span)>>;
260
261    fn impl_is_const(self, def_id: Self::DefId) -> bool;
262    fn fn_is_const(self, def_id: Self::DefId) -> bool;
263    fn alias_has_const_conditions(self, def_id: Self::DefId) -> bool;
264    fn const_conditions(
265        self,
266        def_id: Self::DefId,
267    ) -> ty::EarlyBinder<Self, impl IntoIterator<Item = ty::Binder<Self, ty::TraitRef<Self>>>>;
268    fn explicit_implied_const_bounds(
269        self,
270        def_id: Self::DefId,
271    ) -> ty::EarlyBinder<Self, impl IntoIterator<Item = ty::Binder<Self, ty::TraitRef<Self>>>>;
272
273    fn impl_self_is_guaranteed_unsized(self, def_id: Self::DefId) -> bool;
274
275    fn has_target_features(self, def_id: Self::DefId) -> bool;
276
277    fn require_lang_item(self, lang_item: TraitSolverLangItem) -> Self::DefId;
278
279    fn is_lang_item(self, def_id: Self::DefId, lang_item: TraitSolverLangItem) -> bool;
280
281    fn is_default_trait(self, def_id: Self::DefId) -> bool;
282
283    fn as_lang_item(self, def_id: Self::DefId) -> Option<TraitSolverLangItem>;
284
285    fn associated_type_def_ids(self, def_id: Self::DefId) -> impl IntoIterator<Item = Self::DefId>;
286
287    fn for_each_relevant_impl(
288        self,
289        trait_def_id: Self::DefId,
290        self_ty: Self::Ty,
291        f: impl FnMut(Self::DefId),
292    );
293
294    fn has_item_definition(self, def_id: Self::DefId) -> bool;
295
296    fn impl_specializes(self, impl_def_id: Self::DefId, victim_def_id: Self::DefId) -> bool;
297
298    fn impl_is_default(self, impl_def_id: Self::DefId) -> bool;
299
300    fn impl_trait_ref(self, impl_def_id: Self::DefId) -> ty::EarlyBinder<Self, ty::TraitRef<Self>>;
301
302    fn impl_polarity(self, impl_def_id: Self::DefId) -> ty::ImplPolarity;
303
304    fn trait_is_auto(self, trait_def_id: Self::DefId) -> bool;
305
306    fn trait_is_coinductive(self, trait_def_id: Self::DefId) -> bool;
307
308    fn trait_is_alias(self, trait_def_id: Self::DefId) -> bool;
309
310    fn trait_is_dyn_compatible(self, trait_def_id: Self::DefId) -> bool;
311
312    fn trait_is_fundamental(self, def_id: Self::DefId) -> bool;
313
314    fn trait_may_be_implemented_via_object(self, trait_def_id: Self::DefId) -> bool;
315
316    /// Returns `true` if this is an `unsafe trait`.
317    fn trait_is_unsafe(self, trait_def_id: Self::DefId) -> bool;
318
319    fn is_impl_trait_in_trait(self, def_id: Self::DefId) -> bool;
320
321    fn delay_bug(self, msg: impl ToString) -> Self::ErrorGuaranteed;
322
323    fn is_general_coroutine(self, coroutine_def_id: Self::DefId) -> bool;
324    fn coroutine_is_async(self, coroutine_def_id: Self::DefId) -> bool;
325    fn coroutine_is_gen(self, coroutine_def_id: Self::DefId) -> bool;
326    fn coroutine_is_async_gen(self, coroutine_def_id: Self::DefId) -> bool;
327
328    type UnsizingParams: Deref<Target = DenseBitSet<u32>>;
329    fn unsizing_params_for_adt(self, adt_def_id: Self::DefId) -> Self::UnsizingParams;
330
331    fn find_const_ty_from_env(
332        self,
333        param_env: Self::ParamEnv,
334        placeholder: Self::PlaceholderConst,
335    ) -> Self::Ty;
336
337    fn anonymize_bound_vars<T: TypeFoldable<Self>>(
338        self,
339        binder: ty::Binder<Self, T>,
340    ) -> ty::Binder<Self, T>;
341
342    fn opaque_types_defined_by(self, defining_anchor: Self::LocalDefId) -> Self::LocalDefIds;
343
344    fn opaque_types_and_coroutines_defined_by(
345        self,
346        defining_anchor: Self::LocalDefId,
347    ) -> Self::LocalDefIds;
348}
349
350/// Imagine you have a function `F: FnOnce(&[T]) -> R`, plus an iterator `iter`
351/// that produces `T` items. You could combine them with
352/// `f(&iter.collect::<Vec<_>>())`, but this requires allocating memory for the
353/// `Vec`.
354///
355/// This trait allows for faster implementations, intended for cases where the
356/// number of items produced by the iterator is small. There is a blanket impl
357/// for `T` items, but there is also a fallible impl for `Result<T, E>` items.
358pub trait CollectAndApply<T, R>: Sized {
359    type Output;
360
361    /// Produce a result of type `Self::Output` from `iter`. The result will
362    /// typically be produced by applying `f` on the elements produced by
363    /// `iter`, though this may not happen in some impls, e.g. if an error
364    /// occurred during iteration.
365    fn collect_and_apply<I, F>(iter: I, f: F) -> Self::Output
366    where
367        I: Iterator<Item = Self>,
368        F: FnOnce(&[T]) -> R;
369}
370
371/// The blanket impl that always collects all elements and applies `f`.
372impl<T, R> CollectAndApply<T, R> for T {
373    type Output = R;
374
375    /// Equivalent to `f(&iter.collect::<Vec<_>>())`.
376    fn collect_and_apply<I, F>(mut iter: I, f: F) -> R
377    where
378        I: Iterator<Item = T>,
379        F: FnOnce(&[T]) -> R,
380    {
381        // This code is hot enough that it's worth specializing for the most
382        // common length lists, to avoid the overhead of `SmallVec` creation.
383        // Lengths 0, 1, and 2 typically account for ~95% of cases. If
384        // `size_hint` is incorrect a panic will occur via an `unwrap` or an
385        // `assert`.
386        match iter.size_hint() {
387            (0, Some(0)) => {
388                assert!(iter.next().is_none());
389                f(&[])
390            }
391            (1, Some(1)) => {
392                let t0 = iter.next().unwrap();
393                assert!(iter.next().is_none());
394                f(&[t0])
395            }
396            (2, Some(2)) => {
397                let t0 = iter.next().unwrap();
398                let t1 = iter.next().unwrap();
399                assert!(iter.next().is_none());
400                f(&[t0, t1])
401            }
402            _ => f(&iter.collect::<SmallVec<[_; 8]>>()),
403        }
404    }
405}
406
407/// A fallible impl that will fail, without calling `f`, if there are any
408/// errors during collection.
409impl<T, R, E> CollectAndApply<T, R> for Result<T, E> {
410    type Output = Result<R, E>;
411
412    /// Equivalent to `Ok(f(&iter.collect::<Result<Vec<_>>>()?))`.
413    fn collect_and_apply<I, F>(mut iter: I, f: F) -> Result<R, E>
414    where
415        I: Iterator<Item = Result<T, E>>,
416        F: FnOnce(&[T]) -> R,
417    {
418        // This code is hot enough that it's worth specializing for the most
419        // common length lists, to avoid the overhead of `SmallVec` creation.
420        // Lengths 0, 1, and 2 typically account for ~95% of cases. If
421        // `size_hint` is incorrect a panic will occur via an `unwrap` or an
422        // `assert`, unless a failure happens first, in which case the result
423        // will be an error anyway.
424        Ok(match iter.size_hint() {
425            (0, Some(0)) => {
426                assert!(iter.next().is_none());
427                f(&[])
428            }
429            (1, Some(1)) => {
430                let t0 = iter.next().unwrap()?;
431                assert!(iter.next().is_none());
432                f(&[t0])
433            }
434            (2, Some(2)) => {
435                let t0 = iter.next().unwrap()?;
436                let t1 = iter.next().unwrap()?;
437                assert!(iter.next().is_none());
438                f(&[t0, t1])
439            }
440            _ => f(&iter.collect::<Result<SmallVec<[_; 8]>, _>>()?),
441        })
442    }
443}
444
445impl<I: Interner> search_graph::Cx for I {
446    type Input = CanonicalInput<I>;
447    type Result = QueryResult<I>;
448
449    type DepNodeIndex = I::DepNodeIndex;
450    type Tracked<T: Debug + Clone> = I::Tracked<T>;
451    fn mk_tracked<T: Debug + Clone>(
452        self,
453        data: T,
454        dep_node_index: I::DepNodeIndex,
455    ) -> I::Tracked<T> {
456        I::mk_tracked(self, data, dep_node_index)
457    }
458    fn get_tracked<T: Debug + Clone>(self, tracked: &I::Tracked<T>) -> T {
459        I::get_tracked(self, tracked)
460    }
461    fn with_cached_task<T>(self, task: impl FnOnce() -> T) -> (T, I::DepNodeIndex) {
462        I::with_cached_task(self, task)
463    }
464    fn with_global_cache<R>(self, f: impl FnOnce(&mut search_graph::GlobalCache<Self>) -> R) -> R {
465        I::with_global_cache(self, f)
466    }
467    fn evaluation_is_concurrent(&self) -> bool {
468        self.evaluation_is_concurrent()
469    }
470}
rustc_type_ir/interner.rs

rustc_type_ir/
interner.rs
