1 //! Provides the `RustIrDatabase` implementation for `chalk-solve`
3 //! The purpose of the `chalk_solve::RustIrDatabase` is to get data about
4 //! specific types, such as bounds, where clauses, or fields. This file contains
5 //! the minimal logic to assemble the types for `chalk-solve` by calling out to
6 //! either the `TyCtxt` (for information about types) or
7 //! `crate::chalk::lowering` (to lower rustc types into Chalk types).
9 use rustc_middle::traits::ChalkRustInterner as RustInterner;
10 use rustc_middle::ty::subst::{InternalSubsts, Subst, SubstsRef};
11 use rustc_middle::ty::{self, AssocItemContainer, AssocKind, TyCtxt};
13 use rustc_hir::def_id::DefId;
15 use rustc_span::symbol::sym;
20 use crate::chalk::lowering::LowerInto;
22 pub struct RustIrDatabase<'tcx> {
23 pub tcx: TyCtxt<'tcx>,
24 pub interner: RustInterner<'tcx>,
27 impl fmt::Debug for RustIrDatabase<'_> {
28 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
29 write!(f, "RustIrDatabase")
33 impl<'tcx> chalk_solve::RustIrDatabase<RustInterner<'tcx>> for RustIrDatabase<'tcx> {
34 fn interner(&self) -> &RustInterner<'tcx> {
38 fn associated_ty_data(
40 assoc_type_id: chalk_ir::AssocTypeId<RustInterner<'tcx>>,
41 ) -> Arc<chalk_solve::rust_ir::AssociatedTyDatum<RustInterner<'tcx>>> {
42 let def_id = assoc_type_id.0;
43 let assoc_item = self.tcx.associated_item(def_id);
44 let trait_def_id = match assoc_item.container {
45 AssocItemContainer::TraitContainer(def_id) => def_id,
46 _ => unimplemented!("Not possible??"),
48 match assoc_item.kind {
50 _ => unimplemented!("Not possible??"),
52 let bound_vars = bound_vars_for_item(self.tcx, def_id);
53 let binders = binders_for(&self.interner, bound_vars);
54 // FIXME(chalk): this really isn't right I don't think. The functions
55 // for GATs are a bit hard to figure out. Are these supposed to be where
57 let predicates = self.tcx.predicates_defined_on(def_id).predicates;
58 let where_clauses: Vec<_> = predicates
60 .map(|(wc, _)| wc.subst(self.tcx, &bound_vars))
61 .filter_map(|wc| LowerInto::<Option<chalk_ir::QuantifiedWhereClause<RustInterner<'tcx>>>>::lower_into(wc, &self.interner)).collect();
63 Arc::new(chalk_solve::rust_ir::AssociatedTyDatum {
64 trait_id: chalk_ir::TraitId(trait_def_id),
67 binders: chalk_ir::Binders::new(
69 chalk_solve::rust_ir::AssociatedTyDatumBound { bounds: vec![], where_clauses },
76 trait_id: chalk_ir::TraitId<RustInterner<'tcx>>,
77 ) -> Arc<chalk_solve::rust_ir::TraitDatum<RustInterner<'tcx>>> {
78 let def_id = trait_id.0;
79 let trait_def = self.tcx.trait_def(def_id);
81 let bound_vars = bound_vars_for_item(self.tcx, def_id);
82 let binders = binders_for(&self.interner, bound_vars);
83 let predicates = self.tcx.predicates_defined_on(def_id).predicates;
84 let where_clauses: Vec<_> = predicates
86 .map(|(wc, _)| wc.subst(self.tcx, &bound_vars))
87 .filter_map(|wc| LowerInto::<Option<chalk_ir::QuantifiedWhereClause<RustInterner<'tcx>>>>::lower_into(wc, &self.interner)).collect();
88 let associated_ty_ids: Vec<_> = self
90 .associated_items(def_id)
91 .in_definition_order()
92 .filter(|i| i.kind == AssocKind::Type)
93 .map(|i| chalk_ir::AssocTypeId(i.def_id))
97 if self.tcx.lang_items().sized_trait().map(|t| def_id == t).unwrap_or(false) {
98 Some(chalk_solve::rust_ir::WellKnownTrait::Sized)
99 } else if self.tcx.lang_items().copy_trait().map(|t| def_id == t).unwrap_or(false) {
100 Some(chalk_solve::rust_ir::WellKnownTrait::Copy)
101 } else if self.tcx.lang_items().clone_trait().map(|t| def_id == t).unwrap_or(false) {
102 Some(chalk_solve::rust_ir::WellKnownTrait::Clone)
103 } else if self.tcx.lang_items().drop_trait().map(|t| def_id == t).unwrap_or(false) {
104 Some(chalk_solve::rust_ir::WellKnownTrait::Drop)
105 } else if self.tcx.lang_items().fn_trait().map(|t| def_id == t).unwrap_or(false) {
106 Some(chalk_solve::rust_ir::WellKnownTrait::Fn)
107 } else if self.tcx.lang_items().fn_once_trait().map(|t| def_id == t).unwrap_or(false) {
108 Some(chalk_solve::rust_ir::WellKnownTrait::FnOnce)
109 } else if self.tcx.lang_items().fn_mut_trait().map(|t| def_id == t).unwrap_or(false) {
110 Some(chalk_solve::rust_ir::WellKnownTrait::FnMut)
114 Arc::new(chalk_solve::rust_ir::TraitDatum {
116 binders: chalk_ir::Binders::new(
118 chalk_solve::rust_ir::TraitDatumBound { where_clauses },
120 flags: chalk_solve::rust_ir::TraitFlags {
121 auto: trait_def.has_auto_impl,
122 marker: trait_def.is_marker,
123 upstream: !def_id.is_local(),
124 fundamental: self.tcx.has_attr(def_id, sym::fundamental),
125 non_enumerable: true,
135 adt_id: chalk_ir::AdtId<RustInterner<'tcx>>,
136 ) -> Arc<chalk_solve::rust_ir::AdtDatum<RustInterner<'tcx>>> {
137 let adt_def = adt_id.0;
139 let bound_vars = bound_vars_for_item(self.tcx, adt_def.did);
140 let binders = binders_for(&self.interner, bound_vars);
142 let predicates = self.tcx.predicates_of(adt_def.did).predicates;
143 let where_clauses: Vec<_> = predicates
145 .map(|(wc, _)| wc.subst(self.tcx, bound_vars))
146 .filter_map(|wc| LowerInto::<Option<chalk_ir::QuantifiedWhereClause<RustInterner<'tcx>>>>::lower_into(wc, &self.interner))
148 let fields = match adt_def.adt_kind() {
149 ty::AdtKind::Struct | ty::AdtKind::Union => {
150 let variant = adt_def.non_enum_variant();
157 .subst(self.tcx, bound_vars)
158 .lower_into(&self.interner)
162 // FIXME(chalk): handle enums; force_impl_for requires this
163 ty::AdtKind::Enum => vec![],
165 let struct_datum = Arc::new(chalk_solve::rust_ir::AdtDatum {
167 binders: chalk_ir::Binders::new(
169 chalk_solve::rust_ir::AdtDatumBound { fields, where_clauses },
171 flags: chalk_solve::rust_ir::AdtFlags {
172 upstream: !adt_def.did.is_local(),
173 fundamental: adt_def.is_fundamental(),
174 phantom_data: adt_def.is_phantom_data(),
182 fn_def_id: chalk_ir::FnDefId<RustInterner<'tcx>>,
183 ) -> Arc<chalk_solve::rust_ir::FnDefDatum<RustInterner<'tcx>>> {
184 let def_id = fn_def_id.0;
185 let bound_vars = bound_vars_for_item(self.tcx, def_id);
186 let binders = binders_for(&self.interner, bound_vars);
188 let predicates = self.tcx.predicates_defined_on(def_id).predicates;
189 let where_clauses: Vec<_> = predicates
191 .map(|(wc, _)| wc.subst(self.tcx, &bound_vars))
192 .filter_map(|wc| LowerInto::<Option<chalk_ir::QuantifiedWhereClause<RustInterner<'tcx>>>>::lower_into(wc, &self.interner)).collect();
194 let sig = self.tcx.fn_sig(def_id);
195 let inputs_and_output = sig.inputs_and_output();
196 let (inputs_and_output, iobinders, _) = crate::chalk::lowering::collect_bound_vars(
202 let argument_types = inputs_and_output[..inputs_and_output.len() - 1]
204 .map(|t| t.subst(self.tcx, &bound_vars).lower_into(&self.interner))
207 let return_type = inputs_and_output[inputs_and_output.len() - 1]
208 .subst(self.tcx, &bound_vars)
209 .lower_into(&self.interner);
211 let bound = chalk_solve::rust_ir::FnDefDatumBound {
212 inputs_and_output: chalk_ir::Binders::new(
214 chalk_solve::rust_ir::FnDefInputsAndOutputDatum { argument_types, return_type },
218 Arc::new(chalk_solve::rust_ir::FnDefDatum {
221 binders: chalk_ir::Binders::new(binders, bound),
227 impl_id: chalk_ir::ImplId<RustInterner<'tcx>>,
228 ) -> Arc<chalk_solve::rust_ir::ImplDatum<RustInterner<'tcx>>> {
229 let def_id = impl_id.0;
230 let bound_vars = bound_vars_for_item(self.tcx, def_id);
231 let binders = binders_for(&self.interner, bound_vars);
233 let trait_ref = self.tcx.impl_trait_ref(def_id).expect("not an impl");
234 let trait_ref = trait_ref.subst(self.tcx, bound_vars);
236 let predicates = self.tcx.predicates_of(def_id).predicates;
237 let where_clauses: Vec<_> = predicates
239 .map(|(wc, _)| wc.subst(self.tcx, bound_vars))
240 .filter_map(|wc| LowerInto::<Option<chalk_ir::QuantifiedWhereClause<RustInterner<'tcx>>>>::lower_into(wc, &self.interner)).collect();
242 let value = chalk_solve::rust_ir::ImplDatumBound {
243 trait_ref: trait_ref.lower_into(&self.interner),
247 Arc::new(chalk_solve::rust_ir::ImplDatum {
248 polarity: chalk_solve::rust_ir::Polarity::Positive,
249 binders: chalk_ir::Binders::new(binders, value),
250 impl_type: chalk_solve::rust_ir::ImplType::Local,
251 associated_ty_value_ids: vec![],
257 trait_id: chalk_ir::TraitId<RustInterner<'tcx>>,
258 parameters: &[chalk_ir::GenericArg<RustInterner<'tcx>>],
259 ) -> Vec<chalk_ir::ImplId<RustInterner<'tcx>>> {
260 let def_id = trait_id.0;
262 // FIXME(chalk): use TraitDef::for_each_relevant_impl, but that will
263 // require us to be able to interconvert `Ty<'tcx>`, and we're
266 let all_impls = self.tcx.all_impls(def_id);
267 let matched_impls = all_impls.filter(|impl_def_id| {
268 use chalk_ir::could_match::CouldMatch;
269 let trait_ref = self.tcx.impl_trait_ref(*impl_def_id).unwrap();
270 let bound_vars = bound_vars_for_item(self.tcx, *impl_def_id);
272 let self_ty = trait_ref.self_ty();
273 let self_ty = self_ty.subst(self.tcx, bound_vars);
274 let lowered_ty = self_ty.lower_into(&self.interner);
276 parameters[0].assert_ty_ref(&self.interner).could_match(&self.interner, &lowered_ty)
279 let impls = matched_impls.map(|matched_impl| chalk_ir::ImplId(matched_impl)).collect();
283 fn impl_provided_for(
285 auto_trait_id: chalk_ir::TraitId<RustInterner<'tcx>>,
286 adt_id: chalk_ir::AdtId<RustInterner<'tcx>>,
288 let trait_def_id = auto_trait_id.0;
289 let adt_def = adt_id.0;
290 let all_impls = self.tcx.all_impls(trait_def_id);
291 for impl_def_id in all_impls {
292 let trait_ref = self.tcx.impl_trait_ref(impl_def_id).unwrap();
293 let self_ty = trait_ref.self_ty();
295 ty::Adt(impl_adt_def, _) => {
296 if impl_adt_def == adt_def {
306 fn associated_ty_value(
308 associated_ty_id: chalk_solve::rust_ir::AssociatedTyValueId<RustInterner<'tcx>>,
309 ) -> Arc<chalk_solve::rust_ir::AssociatedTyValue<RustInterner<'tcx>>> {
310 let def_id = associated_ty_id.0;
311 let assoc_item = self.tcx.associated_item(def_id);
312 let impl_id = match assoc_item.container {
313 AssocItemContainer::TraitContainer(def_id) => def_id,
314 _ => unimplemented!("Not possible??"),
316 match assoc_item.kind {
317 AssocKind::Type => {}
318 _ => unimplemented!("Not possible??"),
320 let bound_vars = bound_vars_for_item(self.tcx, def_id);
321 let binders = binders_for(&self.interner, bound_vars);
322 let ty = self.tcx.type_of(def_id);
324 Arc::new(chalk_solve::rust_ir::AssociatedTyValue {
325 impl_id: chalk_ir::ImplId(impl_id),
326 associated_ty_id: chalk_ir::AssocTypeId(def_id),
327 value: chalk_ir::Binders::new(
329 chalk_solve::rust_ir::AssociatedTyValueBound { ty: ty.lower_into(&self.interner) },
334 fn custom_clauses(&self) -> Vec<chalk_ir::ProgramClause<RustInterner<'tcx>>> {
338 fn local_impls_to_coherence_check(
340 _trait_id: chalk_ir::TraitId<RustInterner<'tcx>>,
341 ) -> Vec<chalk_ir::ImplId<RustInterner<'tcx>>> {
347 opaque_ty_id: chalk_ir::OpaqueTyId<RustInterner<'tcx>>,
348 ) -> Arc<chalk_solve::rust_ir::OpaqueTyDatum<RustInterner<'tcx>>> {
349 let bound_vars = bound_vars_for_item(self.tcx, opaque_ty_id.0);
350 let binders = binders_for(&self.interner, bound_vars);
351 let predicates = self.tcx.predicates_defined_on(opaque_ty_id.0).predicates;
352 let where_clauses: Vec<_> = predicates
354 .map(|(wc, _)| wc.subst(self.tcx, &bound_vars))
355 .filter_map(|wc| LowerInto::<Option<chalk_ir::QuantifiedWhereClause<RustInterner<'tcx>>>>::lower_into(wc, &self.interner)).collect();
357 let value = chalk_solve::rust_ir::OpaqueTyDatumBound {
358 bounds: chalk_ir::Binders::new(binders, where_clauses),
360 Arc::new(chalk_solve::rust_ir::OpaqueTyDatum {
362 bound: chalk_ir::Binders::new(chalk_ir::VariableKinds::new(&self.interner), value),
366 /// Since Chalk can't handle all Rust types currently, we have to handle
367 /// some specially for now. Over time, these `Some` returns will change to
368 /// `None` and eventually this function will be removed.
371 well_known: chalk_solve::rust_ir::WellKnownTrait,
372 ty: &chalk_ir::TyData<RustInterner<'tcx>>,
374 use chalk_ir::TyData::*;
376 chalk_solve::rust_ir::WellKnownTrait::Sized => match ty {
377 Apply(apply) => match apply.name {
378 chalk_ir::TypeName::Adt(chalk_ir::AdtId(adt_def)) => match adt_def.adt_kind() {
379 ty::AdtKind::Struct | ty::AdtKind::Union => None,
380 ty::AdtKind::Enum => {
381 let constraint = self.tcx.adt_sized_constraint(adt_def.did);
382 if constraint.0.len() > 0 { unimplemented!() } else { Some(true) }
392 | BoundVar(_) => None,
394 chalk_solve::rust_ir::WellKnownTrait::Copy
395 | chalk_solve::rust_ir::WellKnownTrait::Clone => match ty {
396 Apply(apply) => match apply.name {
397 chalk_ir::TypeName::Adt(chalk_ir::AdtId(adt_def)) => match adt_def.adt_kind() {
398 ty::AdtKind::Struct | ty::AdtKind::Union => None,
399 ty::AdtKind::Enum => {
400 let constraint = self.tcx.adt_sized_constraint(adt_def.did);
401 if constraint.0.len() > 0 { unimplemented!() } else { Some(true) }
411 | BoundVar(_) => None,
413 chalk_solve::rust_ir::WellKnownTrait::Drop => None,
414 chalk_solve::rust_ir::WellKnownTrait::Fn => None,
415 chalk_solve::rust_ir::WellKnownTrait::FnMut => None,
416 chalk_solve::rust_ir::WellKnownTrait::FnOnce => None,
417 chalk_solve::rust_ir::WellKnownTrait::Unsize => None,
421 fn program_clauses_for_env(
423 environment: &chalk_ir::Environment<RustInterner<'tcx>>,
424 ) -> chalk_ir::ProgramClauses<RustInterner<'tcx>> {
425 chalk_solve::program_clauses_for_env(self, environment)
428 fn well_known_trait_id(
430 well_known_trait: chalk_solve::rust_ir::WellKnownTrait,
431 ) -> Option<chalk_ir::TraitId<RustInterner<'tcx>>> {
432 use chalk_solve::rust_ir::WellKnownTrait::*;
433 let def_id = match well_known_trait {
434 Sized => self.tcx.lang_items().sized_trait(),
435 Copy => self.tcx.lang_items().copy_trait(),
436 Clone => self.tcx.lang_items().clone_trait(),
437 Drop => self.tcx.lang_items().drop_trait(),
438 Fn => self.tcx.lang_items().fn_trait(),
439 FnMut => self.tcx.lang_items().fn_mut_trait(),
440 FnOnce => self.tcx.lang_items().fn_once_trait(),
441 Unsize => self.tcx.lang_items().unsize_trait(),
443 def_id.map(|t| chalk_ir::TraitId(t))
446 fn is_object_safe(&self, trait_id: chalk_ir::TraitId<RustInterner<'tcx>>) -> bool {
447 self.tcx.is_object_safe(trait_id.0)
450 fn hidden_opaque_type(
452 _id: chalk_ir::OpaqueTyId<RustInterner<'tcx>>,
453 ) -> chalk_ir::Ty<RustInterner<'tcx>> {
454 // FIXME(chalk): actually get hidden ty
455 self.tcx.mk_ty(ty::Tuple(self.tcx.intern_substs(&[]))).lower_into(&self.interner)
460 _closure_id: chalk_ir::ClosureId<RustInterner<'tcx>>,
461 substs: &chalk_ir::Substitution<RustInterner<'tcx>>,
462 ) -> chalk_solve::rust_ir::ClosureKind {
463 let kind = &substs.parameters(&self.interner)[substs.len(&self.interner) - 3];
464 match kind.assert_ty_ref(&self.interner).data(&self.interner) {
465 chalk_ir::TyData::Apply(apply) => match apply.name {
466 chalk_ir::TypeName::Scalar(scalar) => match scalar {
467 chalk_ir::Scalar::Int(int_ty) => match int_ty {
468 chalk_ir::IntTy::I8 => chalk_solve::rust_ir::ClosureKind::Fn,
469 chalk_ir::IntTy::I16 => chalk_solve::rust_ir::ClosureKind::FnMut,
470 chalk_ir::IntTy::I32 => chalk_solve::rust_ir::ClosureKind::FnOnce,
471 _ => bug!("bad closure kind"),
473 _ => bug!("bad closure kind"),
475 _ => bug!("bad closure kind"),
477 _ => bug!("bad closure kind"),
481 fn closure_inputs_and_output(
483 _closure_id: chalk_ir::ClosureId<RustInterner<'tcx>>,
484 substs: &chalk_ir::Substitution<RustInterner<'tcx>>,
485 ) -> chalk_ir::Binders<chalk_solve::rust_ir::FnDefInputsAndOutputDatum<RustInterner<'tcx>>>
487 let sig = &substs.parameters(&self.interner)[substs.len(&self.interner) - 2];
488 match sig.assert_ty_ref(&self.interner).data(&self.interner) {
489 chalk_ir::TyData::Function(f) => {
490 let substitution = f.substitution.parameters(&self.interner);
492 substitution.last().unwrap().assert_ty_ref(&self.interner).clone();
493 // Closure arguments are tupled
494 let argument_tuple = substitution[0].assert_ty_ref(&self.interner);
495 let argument_types = match argument_tuple.data(&self.interner) {
496 chalk_ir::TyData::Apply(apply) => match apply.name {
497 chalk_ir::TypeName::Tuple(_) => apply
499 .iter(&self.interner)
500 .map(|arg| arg.assert_ty_ref(&self.interner))
503 _ => bug!("Expecting closure FnSig args to be tupled."),
505 _ => bug!("Expecting closure FnSig args to be tupled."),
508 chalk_ir::Binders::new(
509 chalk_ir::VariableKinds::from(
511 (0..f.num_binders).map(|_| chalk_ir::VariableKind::Lifetime),
513 chalk_solve::rust_ir::FnDefInputsAndOutputDatum { argument_types, return_type },
516 _ => panic!("Invalid sig."),
522 _closure_id: chalk_ir::ClosureId<RustInterner<'tcx>>,
523 substs: &chalk_ir::Substitution<RustInterner<'tcx>>,
524 ) -> chalk_ir::Binders<chalk_ir::Ty<RustInterner<'tcx>>> {
525 let inputs_and_output = self.closure_inputs_and_output(_closure_id, substs);
526 let tuple = substs.parameters(&self.interner).last().unwrap().assert_ty_ref(&self.interner);
527 inputs_and_output.map_ref(|_| tuple.clone())
530 fn closure_fn_substitution(
532 _closure_id: chalk_ir::ClosureId<RustInterner<'tcx>>,
533 substs: &chalk_ir::Substitution<RustInterner<'tcx>>,
534 ) -> chalk_ir::Substitution<RustInterner<'tcx>> {
535 let substitution = &substs.parameters(&self.interner)[0..substs.len(&self.interner) - 3];
536 chalk_ir::Substitution::from(&self.interner, substitution)
540 /// Creates a `InternalSubsts` that maps each generic parameter to a higher-ranked
541 /// var bound at index `0`. For types, we use a `BoundVar` index equal to
542 /// the type parameter index. For regions, we use the `BoundRegion::BrNamed`
543 /// variant (which has a `DefId`).
544 fn bound_vars_for_item(tcx: TyCtxt<'tcx>, def_id: DefId) -> SubstsRef<'tcx> {
545 InternalSubsts::for_item(tcx, def_id, |param, substs| match param.kind {
546 ty::GenericParamDefKind::Type { .. } => tcx
550 var: ty::BoundVar::from(param.index),
551 kind: ty::BoundTyKind::Param(param.name),
556 ty::GenericParamDefKind::Lifetime => tcx
557 .mk_region(ty::RegionKind::ReLateBound(
559 ty::BoundRegion::BrAnon(substs.len() as u32),
563 ty::GenericParamDefKind::Const => tcx
564 .mk_const(ty::Const {
565 val: ty::ConstKind::Bound(ty::INNERMOST, ty::BoundVar::from(param.index)),
566 ty: tcx.type_of(param.def_id),
572 fn binders_for<'tcx>(
573 interner: &RustInterner<'tcx>,
574 bound_vars: SubstsRef<'tcx>,
575 ) -> chalk_ir::VariableKinds<RustInterner<'tcx>> {
576 chalk_ir::VariableKinds::from(
578 bound_vars.iter().map(|arg| match arg.unpack() {
579 ty::subst::GenericArgKind::Lifetime(_re) => chalk_ir::VariableKind::Lifetime,
580 ty::subst::GenericArgKind::Type(_ty) => {
581 chalk_ir::VariableKind::Ty(chalk_ir::TyKind::General)
583 ty::subst::GenericArgKind::Const(c) => {
584 chalk_ir::VariableKind::Const(c.ty.lower_into(interner))