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Commit | Line | Data |
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1b1a35ee | 1 | use super::callee::DeferredCallResolution; |
1b1a35ee | 2 | |
c295e0f8 | 3 | use rustc_data_structures::fx::FxHashSet; |
f2b60f7d | 4 | use rustc_data_structures::sync::Lrc; |
1b1a35ee | 5 | use rustc_hir as hir; |
064997fb | 6 | use rustc_hir::def_id::LocalDefId; |
1b1a35ee XL |
7 | use rustc_hir::HirIdMap; |
8 | use rustc_infer::infer; | |
9 | use rustc_infer::infer::{InferCtxt, InferOk, TyCtxtInferExt}; | |
10 | use rustc_middle::ty::fold::TypeFoldable; | |
064997fb | 11 | use rustc_middle::ty::visit::TypeVisitable; |
94222f64 | 12 | use rustc_middle::ty::{self, Ty, TyCtxt}; |
064997fb | 13 | use rustc_span::def_id::LocalDefIdMap; |
1b1a35ee XL |
14 | use rustc_span::{self, Span}; |
15 | use rustc_trait_selection::infer::InferCtxtExt as _; | |
f2b60f7d FG |
16 | use rustc_trait_selection::traits::{ |
17 | self, ObligationCause, ObligationCtxt, TraitEngine, TraitEngineExt as _, | |
18 | }; | |
1b1a35ee XL |
19 | |
20 | use std::cell::RefCell; | |
21 | use std::ops::Deref; | |
22 | ||
23 | /// Closures defined within the function. For example: | |
04454e1e FG |
24 | /// ```ignore (illustrative) |
25 | /// fn foo() { | |
26 | /// bar(move|| { ... }) | |
27 | /// } | |
28 | /// ``` | |
1b1a35ee XL |
29 | /// Here, the function `foo()` and the closure passed to |
30 | /// `bar()` will each have their own `FnCtxt`, but they will | |
31 | /// share the inherited fields. | |
32 | pub struct Inherited<'a, 'tcx> { | |
33 | pub(super) infcx: InferCtxt<'a, 'tcx>, | |
34 | ||
064997fb | 35 | pub(super) typeck_results: &'a RefCell<ty::TypeckResults<'tcx>>, |
1b1a35ee XL |
36 | |
37 | pub(super) locals: RefCell<HirIdMap<super::LocalTy<'tcx>>>, | |
38 | ||
39 | pub(super) fulfillment_cx: RefCell<Box<dyn TraitEngine<'tcx>>>, | |
40 | ||
41 | // Some additional `Sized` obligations badly affect type inference. | |
42 | // These obligations are added in a later stage of typeck. | |
f2b60f7d | 43 | // Removing these may also cause additional complications, see #101066. |
1b1a35ee XL |
44 | pub(super) deferred_sized_obligations: |
45 | RefCell<Vec<(Ty<'tcx>, Span, traits::ObligationCauseCode<'tcx>)>>, | |
46 | ||
47 | // When we process a call like `c()` where `c` is a closure type, | |
48 | // we may not have decided yet whether `c` is a `Fn`, `FnMut`, or | |
49 | // `FnOnce` closure. In that case, we defer full resolution of the | |
50 | // call until upvar inference can kick in and make the | |
51 | // decision. We keep these deferred resolutions grouped by the | |
52 | // def-id of the closure, so that once we decide, we can easily go | |
53 | // back and process them. | |
064997fb | 54 | pub(super) deferred_call_resolutions: RefCell<LocalDefIdMap<Vec<DeferredCallResolution<'tcx>>>>, |
1b1a35ee XL |
55 | |
56 | pub(super) deferred_cast_checks: RefCell<Vec<super::cast::CastCheck<'tcx>>>, | |
57 | ||
923072b8 FG |
58 | pub(super) deferred_transmute_checks: RefCell<Vec<(Ty<'tcx>, Ty<'tcx>, Span)>>, |
59 | ||
60 | pub(super) deferred_asm_checks: RefCell<Vec<(&'tcx hir::InlineAsm<'tcx>, hir::HirId)>>, | |
61 | ||
1b1a35ee XL |
62 | pub(super) deferred_generator_interiors: |
63 | RefCell<Vec<(hir::BodyId, Ty<'tcx>, hir::GeneratorKind)>>, | |
64 | ||
1b1a35ee | 65 | pub(super) body_id: Option<hir::BodyId>, |
c295e0f8 XL |
66 | |
67 | /// Whenever we introduce an adjustment from `!` into a type variable, | |
68 | /// we record that type variable here. This is later used to inform | |
69 | /// fallback. See the `fallback` module for details. | |
70 | pub(super) diverging_type_vars: RefCell<FxHashSet<Ty<'tcx>>>, | |
1b1a35ee XL |
71 | } |
72 | ||
73 | impl<'a, 'tcx> Deref for Inherited<'a, 'tcx> { | |
74 | type Target = InferCtxt<'a, 'tcx>; | |
75 | fn deref(&self) -> &Self::Target { | |
76 | &self.infcx | |
77 | } | |
78 | } | |
79 | ||
5e7ed085 FG |
80 | /// A temporary returned by `Inherited::build(...)`. This is necessary |
81 | /// for multiple `InferCtxt` to share the same `in_progress_typeck_results` | |
82 | /// without using `Rc` or something similar. | |
1b1a35ee XL |
83 | pub struct InheritedBuilder<'tcx> { |
84 | infcx: infer::InferCtxtBuilder<'tcx>, | |
85 | def_id: LocalDefId, | |
86 | } | |
87 | ||
a2a8927a | 88 | impl<'tcx> Inherited<'_, 'tcx> { |
1b1a35ee XL |
89 | pub fn build(tcx: TyCtxt<'tcx>, def_id: LocalDefId) -> InheritedBuilder<'tcx> { |
90 | let hir_owner = tcx.hir().local_def_id_to_hir_id(def_id).owner; | |
91 | ||
92 | InheritedBuilder { | |
064997fb FG |
93 | infcx: tcx |
94 | .infer_ctxt() | |
95 | .ignoring_regions() | |
f2b60f7d FG |
96 | .with_fresh_in_progress_typeck_results(hir_owner) |
97 | .with_normalize_fn_sig_for_diagnostic(Lrc::new(move |infcx, fn_sig| { | |
98 | if fn_sig.has_escaping_bound_vars() { | |
99 | return fn_sig; | |
100 | } | |
101 | infcx.probe(|_| { | |
102 | let ocx = ObligationCtxt::new_in_snapshot(infcx); | |
103 | let normalized_fn_sig = ocx.normalize( | |
104 | ObligationCause::dummy(), | |
105 | // FIXME(compiler-errors): This is probably not the right param-env... | |
106 | infcx.tcx.param_env(def_id), | |
107 | fn_sig, | |
108 | ); | |
109 | if ocx.select_all_or_error().is_empty() { | |
110 | let normalized_fn_sig = | |
111 | infcx.resolve_vars_if_possible(normalized_fn_sig); | |
112 | if !normalized_fn_sig.needs_infer() { | |
113 | return normalized_fn_sig; | |
114 | } | |
115 | } | |
116 | fn_sig | |
117 | }) | |
118 | })), | |
1b1a35ee XL |
119 | def_id, |
120 | } | |
121 | } | |
122 | } | |
123 | ||
124 | impl<'tcx> InheritedBuilder<'tcx> { | |
125 | pub fn enter<F, R>(&mut self, f: F) -> R | |
126 | where | |
127 | F: for<'a> FnOnce(Inherited<'a, 'tcx>) -> R, | |
128 | { | |
129 | let def_id = self.def_id; | |
130 | self.infcx.enter(|infcx| f(Inherited::new(infcx, def_id))) | |
131 | } | |
132 | } | |
133 | ||
a2a8927a | 134 | impl<'a, 'tcx> Inherited<'a, 'tcx> { |
064997fb | 135 | fn new(infcx: InferCtxt<'a, 'tcx>, def_id: LocalDefId) -> Self { |
1b1a35ee | 136 | let tcx = infcx.tcx; |
064997fb FG |
137 | let body_id = tcx.hir().maybe_body_owned_by(def_id); |
138 | let typeck_results = | |
139 | infcx.in_progress_typeck_results.expect("building `FnCtxt` without typeck results"); | |
1b1a35ee XL |
140 | |
141 | Inherited { | |
064997fb | 142 | typeck_results, |
1b1a35ee | 143 | infcx, |
6a06907d | 144 | fulfillment_cx: RefCell::new(<dyn TraitEngine<'_>>::new(tcx)), |
1b1a35ee XL |
145 | locals: RefCell::new(Default::default()), |
146 | deferred_sized_obligations: RefCell::new(Vec::new()), | |
147 | deferred_call_resolutions: RefCell::new(Default::default()), | |
148 | deferred_cast_checks: RefCell::new(Vec::new()), | |
923072b8 FG |
149 | deferred_transmute_checks: RefCell::new(Vec::new()), |
150 | deferred_asm_checks: RefCell::new(Vec::new()), | |
1b1a35ee | 151 | deferred_generator_interiors: RefCell::new(Vec::new()), |
c295e0f8 | 152 | diverging_type_vars: RefCell::new(Default::default()), |
1b1a35ee XL |
153 | body_id, |
154 | } | |
155 | } | |
156 | ||
5e7ed085 | 157 | #[instrument(level = "debug", skip(self))] |
1b1a35ee | 158 | pub(super) fn register_predicate(&self, obligation: traits::PredicateObligation<'tcx>) { |
1b1a35ee XL |
159 | if obligation.has_escaping_bound_vars() { |
160 | span_bug!(obligation.cause.span, "escaping bound vars in predicate {:?}", obligation); | |
161 | } | |
162 | self.fulfillment_cx.borrow_mut().register_predicate_obligation(self, obligation); | |
163 | } | |
164 | ||
165 | pub(super) fn register_predicates<I>(&self, obligations: I) | |
166 | where | |
167 | I: IntoIterator<Item = traits::PredicateObligation<'tcx>>, | |
168 | { | |
169 | for obligation in obligations { | |
170 | self.register_predicate(obligation); | |
171 | } | |
172 | } | |
173 | ||
174 | pub(super) fn register_infer_ok_obligations<T>(&self, infer_ok: InferOk<'tcx, T>) -> T { | |
175 | self.register_predicates(infer_ok.obligations); | |
176 | infer_ok.value | |
177 | } | |
178 | ||
179 | pub(super) fn normalize_associated_types_in<T>( | |
180 | &self, | |
181 | span: Span, | |
182 | body_id: hir::HirId, | |
183 | param_env: ty::ParamEnv<'tcx>, | |
fc512014 | 184 | value: T, |
1b1a35ee XL |
185 | ) -> T |
186 | where | |
187 | T: TypeFoldable<'tcx>, | |
188 | { | |
136023e0 XL |
189 | self.normalize_associated_types_in_with_cause( |
190 | ObligationCause::misc(span, body_id), | |
191 | param_env, | |
192 | value, | |
193 | ) | |
194 | } | |
195 | ||
196 | pub(super) fn normalize_associated_types_in_with_cause<T>( | |
197 | &self, | |
198 | cause: ObligationCause<'tcx>, | |
199 | param_env: ty::ParamEnv<'tcx>, | |
200 | value: T, | |
201 | ) -> T | |
202 | where | |
203 | T: TypeFoldable<'tcx>, | |
204 | { | |
205 | let ok = self.partially_normalize_associated_types_in(cause, param_env, value); | |
206 | debug!(?ok); | |
1b1a35ee XL |
207 | self.register_infer_ok_obligations(ok) |
208 | } | |
209 | } |