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::{self, AssocKind, EarlyBinder, Ty, TyCtxt, TypeFoldable, TypeSuperFoldable};
11 use rustc_middle::ty::{InternalSubsts, SubstsRef};
12 use rustc_target::abi::{Integer, IntegerType};
16 use rustc_hir::def_id::DefId;
18 use rustc_span::symbol::sym;
23 use crate::chalk::lowering::LowerInto;
25 pub struct RustIrDatabase<'tcx> {
26 pub(crate) interner: RustInterner<'tcx>,
29 impl fmt::Debug for RustIrDatabase<'_> {
30 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
31 write!(f, "RustIrDatabase")
35 impl<'tcx> RustIrDatabase<'tcx> {
39 bound_vars: SubstsRef<'tcx>,
40 ) -> Vec<chalk_ir::QuantifiedWhereClause<RustInterner<'tcx>>> {
41 let predicates = self.interner.tcx.predicates_defined_on(def_id).predicates;
44 .map(|(wc, _)| EarlyBinder(*wc).subst(self.interner.tcx, bound_vars))
45 .filter_map(|wc| LowerInto::<
46 Option<chalk_ir::QuantifiedWhereClause<RustInterner<'tcx>>>
47 >::lower_into(wc, self.interner)).collect()
50 fn bounds_for<T>(&self, def_id: DefId, bound_vars: SubstsRef<'tcx>) -> Vec<T>
52 ty::Predicate<'tcx>: LowerInto<'tcx, std::option::Option<T>>,
54 let bounds = self.interner.tcx.bound_explicit_item_bounds(def_id);
58 .map(|(bound, _)| bounds.rebind(*bound).subst(self.interner.tcx, &bound_vars))
59 .filter_map(|bound| LowerInto::<Option<_>>::lower_into(bound, self.interner))
64 impl<'tcx> chalk_solve::RustIrDatabase<RustInterner<'tcx>> for RustIrDatabase<'tcx> {
65 fn interner(&self) -> RustInterner<'tcx> {
69 fn associated_ty_data(
71 assoc_type_id: chalk_ir::AssocTypeId<RustInterner<'tcx>>,
72 ) -> Arc<chalk_solve::rust_ir::AssociatedTyDatum<RustInterner<'tcx>>> {
73 let def_id = assoc_type_id.0;
74 let assoc_item = self.interner.tcx.associated_item(def_id);
75 let Some(trait_def_id) = assoc_item.trait_container(self.interner.tcx) else {
76 unimplemented!("Not possible??");
78 match assoc_item.kind {
80 _ => unimplemented!("Not possible??"),
82 let bound_vars = bound_vars_for_item(self.interner.tcx, def_id);
83 let binders = binders_for(self.interner, bound_vars);
85 let where_clauses = self.where_clauses_for(def_id, bound_vars);
86 let bounds = self.bounds_for(def_id, bound_vars);
88 Arc::new(chalk_solve::rust_ir::AssociatedTyDatum {
89 trait_id: chalk_ir::TraitId(trait_def_id),
92 binders: chalk_ir::Binders::new(
94 chalk_solve::rust_ir::AssociatedTyDatumBound { bounds, where_clauses },
101 trait_id: chalk_ir::TraitId<RustInterner<'tcx>>,
102 ) -> Arc<chalk_solve::rust_ir::TraitDatum<RustInterner<'tcx>>> {
103 use chalk_solve::rust_ir::WellKnownTrait::*;
105 let def_id = trait_id.0;
106 let trait_def = self.interner.tcx.trait_def(def_id);
108 let bound_vars = bound_vars_for_item(self.interner.tcx, def_id);
109 let binders = binders_for(self.interner, bound_vars);
111 let where_clauses = self.where_clauses_for(def_id, bound_vars);
113 let associated_ty_ids: Vec<_> = self
116 .associated_items(def_id)
117 .in_definition_order()
118 .filter(|i| i.kind == AssocKind::Type)
119 .map(|i| chalk_ir::AssocTypeId(i.def_id))
122 let lang_items = self.interner.tcx.lang_items();
123 let well_known = if lang_items.sized_trait() == Some(def_id) {
125 } else if lang_items.copy_trait() == Some(def_id) {
127 } else if lang_items.clone_trait() == Some(def_id) {
129 } else if lang_items.drop_trait() == Some(def_id) {
131 } else if lang_items.fn_trait() == Some(def_id) {
133 } else if lang_items.fn_once_trait() == Some(def_id) {
135 } else if lang_items.fn_mut_trait() == Some(def_id) {
137 } else if lang_items.unsize_trait() == Some(def_id) {
139 } else if lang_items.unpin_trait() == Some(def_id) {
141 } else if lang_items.coerce_unsized_trait() == Some(def_id) {
143 } else if lang_items.dispatch_from_dyn_trait() == Some(def_id) {
144 Some(DispatchFromDyn)
145 } else if lang_items.tuple_trait() == Some(def_id) {
150 Arc::new(chalk_solve::rust_ir::TraitDatum {
152 binders: chalk_ir::Binders::new(
154 chalk_solve::rust_ir::TraitDatumBound { where_clauses },
156 flags: chalk_solve::rust_ir::TraitFlags {
157 auto: trait_def.has_auto_impl,
158 marker: trait_def.is_marker,
159 upstream: !def_id.is_local(),
160 fundamental: self.interner.tcx.has_attr(def_id, sym::fundamental),
161 non_enumerable: true,
171 adt_id: chalk_ir::AdtId<RustInterner<'tcx>>,
172 ) -> Arc<chalk_solve::rust_ir::AdtDatum<RustInterner<'tcx>>> {
173 let adt_def = adt_id.0;
175 let bound_vars = bound_vars_for_item(self.interner.tcx, adt_def.did());
176 let binders = binders_for(self.interner, bound_vars);
178 let where_clauses = self.where_clauses_for(adt_def.did(), bound_vars);
180 let variants: Vec<_> = adt_def
183 .map(|variant| chalk_solve::rust_ir::AdtVariantDatum {
187 .map(|field| field.ty(self.interner.tcx, bound_vars).lower_into(self.interner))
191 Arc::new(chalk_solve::rust_ir::AdtDatum {
193 binders: chalk_ir::Binders::new(
195 chalk_solve::rust_ir::AdtDatumBound { variants, where_clauses },
197 flags: chalk_solve::rust_ir::AdtFlags {
198 upstream: !adt_def.did().is_local(),
199 fundamental: adt_def.is_fundamental(),
200 phantom_data: adt_def.is_phantom_data(),
202 kind: match adt_def.adt_kind() {
203 ty::AdtKind::Struct => chalk_solve::rust_ir::AdtKind::Struct,
204 ty::AdtKind::Union => chalk_solve::rust_ir::AdtKind::Union,
205 ty::AdtKind::Enum => chalk_solve::rust_ir::AdtKind::Enum,
212 adt_id: chalk_ir::AdtId<RustInterner<'tcx>>,
213 ) -> Arc<chalk_solve::rust_ir::AdtRepr<RustInterner<'tcx>>> {
214 let adt_def = adt_id.0;
215 let int = |i| chalk_ir::TyKind::Scalar(chalk_ir::Scalar::Int(i)).intern(self.interner);
216 let uint = |i| chalk_ir::TyKind::Scalar(chalk_ir::Scalar::Uint(i)).intern(self.interner);
217 Arc::new(chalk_solve::rust_ir::AdtRepr {
218 c: adt_def.repr().c(),
219 packed: adt_def.repr().packed(),
220 int: adt_def.repr().int.map(|i| match i {
221 IntegerType::Pointer(true) => int(chalk_ir::IntTy::Isize),
222 IntegerType::Pointer(false) => uint(chalk_ir::UintTy::Usize),
223 IntegerType::Fixed(i, true) => match i {
224 Integer::I8 => int(chalk_ir::IntTy::I8),
225 Integer::I16 => int(chalk_ir::IntTy::I16),
226 Integer::I32 => int(chalk_ir::IntTy::I32),
227 Integer::I64 => int(chalk_ir::IntTy::I64),
228 Integer::I128 => int(chalk_ir::IntTy::I128),
230 IntegerType::Fixed(i, false) => match i {
231 Integer::I8 => uint(chalk_ir::UintTy::U8),
232 Integer::I16 => uint(chalk_ir::UintTy::U16),
233 Integer::I32 => uint(chalk_ir::UintTy::U32),
234 Integer::I64 => uint(chalk_ir::UintTy::U64),
235 Integer::I128 => uint(chalk_ir::UintTy::U128),
243 adt_id: chalk_ir::AdtId<RustInterner<'tcx>>,
244 ) -> Arc<chalk_solve::rust_ir::AdtSizeAlign> {
245 let tcx = self.interner.tcx;
246 let did = adt_id.0.did();
248 // Grab the ADT and the param we might need to calculate its layout
249 let param_env = tcx.param_env(did);
250 let adt_ty = tcx.type_of(did);
252 // The ADT is a 1-zst if it's a ZST and its alignment is 1.
253 // Mark the ADT as _not_ a 1-zst if there was a layout error.
254 let one_zst = if let Ok(layout) = tcx.layout_of(param_env.and(adt_ty)) {
255 layout.is_zst() && layout.align.abi.bytes() == 1
260 Arc::new(chalk_solve::rust_ir::AdtSizeAlign::from_one_zst(one_zst))
265 fn_def_id: chalk_ir::FnDefId<RustInterner<'tcx>>,
266 ) -> Arc<chalk_solve::rust_ir::FnDefDatum<RustInterner<'tcx>>> {
267 let def_id = fn_def_id.0;
268 let bound_vars = bound_vars_for_item(self.interner.tcx, def_id);
269 let binders = binders_for(self.interner, bound_vars);
271 let where_clauses = self.where_clauses_for(def_id, bound_vars);
273 let sig = self.interner.tcx.bound_fn_sig(def_id);
274 let (inputs_and_output, iobinders, _) = crate::chalk::lowering::collect_bound_vars(
277 sig.map_bound(|s| s.inputs_and_output()).subst(self.interner.tcx, bound_vars),
280 let argument_types = inputs_and_output[..inputs_and_output.len() - 1]
282 .map(|t| sig.rebind(*t).subst(self.interner.tcx, &bound_vars).lower_into(self.interner))
285 let return_type = sig
286 .rebind(inputs_and_output[inputs_and_output.len() - 1])
287 .subst(self.interner.tcx, &bound_vars)
288 .lower_into(self.interner);
290 let bound = chalk_solve::rust_ir::FnDefDatumBound {
291 inputs_and_output: chalk_ir::Binders::new(
293 chalk_solve::rust_ir::FnDefInputsAndOutputDatum { argument_types, return_type },
297 Arc::new(chalk_solve::rust_ir::FnDefDatum {
299 sig: sig.0.lower_into(self.interner),
300 binders: chalk_ir::Binders::new(binders, bound),
306 impl_id: chalk_ir::ImplId<RustInterner<'tcx>>,
307 ) -> Arc<chalk_solve::rust_ir::ImplDatum<RustInterner<'tcx>>> {
308 let def_id = impl_id.0;
309 let bound_vars = bound_vars_for_item(self.interner.tcx, def_id);
310 let binders = binders_for(self.interner, bound_vars);
312 let trait_ref = self.interner.tcx.bound_impl_trait_ref(def_id).expect("not an impl");
313 let trait_ref = trait_ref.subst(self.interner.tcx, bound_vars);
315 let where_clauses = self.where_clauses_for(def_id, bound_vars);
317 let value = chalk_solve::rust_ir::ImplDatumBound {
318 trait_ref: trait_ref.lower_into(self.interner),
322 let associated_ty_value_ids: Vec<_> = self
325 .associated_items(def_id)
326 .in_definition_order()
327 .filter(|i| i.kind == AssocKind::Type)
328 .map(|i| chalk_solve::rust_ir::AssociatedTyValueId(i.def_id))
331 Arc::new(chalk_solve::rust_ir::ImplDatum {
332 polarity: self.interner.tcx.impl_polarity(def_id).lower_into(self.interner),
333 binders: chalk_ir::Binders::new(binders, value),
334 impl_type: chalk_solve::rust_ir::ImplType::Local,
335 associated_ty_value_ids,
341 trait_id: chalk_ir::TraitId<RustInterner<'tcx>>,
342 parameters: &[chalk_ir::GenericArg<RustInterner<'tcx>>],
343 _binders: &chalk_ir::CanonicalVarKinds<RustInterner<'tcx>>,
344 ) -> Vec<chalk_ir::ImplId<RustInterner<'tcx>>> {
345 let def_id = trait_id.0;
347 // FIXME(chalk): use TraitDef::for_each_relevant_impl, but that will
348 // require us to be able to interconvert `Ty<'tcx>`, and we're
351 let all_impls = self.interner.tcx.all_impls(def_id);
352 let matched_impls = all_impls.filter(|impl_def_id| {
353 use chalk_ir::could_match::CouldMatch;
354 let trait_ref = self.interner.tcx.bound_impl_trait_ref(*impl_def_id).unwrap();
355 let bound_vars = bound_vars_for_item(self.interner.tcx, *impl_def_id);
357 let self_ty = trait_ref.map_bound(|t| t.self_ty());
358 let self_ty = self_ty.subst(self.interner.tcx, bound_vars);
359 let lowered_ty = self_ty.lower_into(self.interner);
361 parameters[0].assert_ty_ref(self.interner).could_match(
363 self.unification_database(),
368 let impls = matched_impls.map(chalk_ir::ImplId).collect();
372 fn impl_provided_for(
374 auto_trait_id: chalk_ir::TraitId<RustInterner<'tcx>>,
375 chalk_ty: &chalk_ir::TyKind<RustInterner<'tcx>>,
377 use chalk_ir::Scalar::*;
378 use chalk_ir::TyKind::*;
380 let trait_def_id = auto_trait_id.0;
381 let all_impls = self.interner.tcx.all_impls(trait_def_id);
382 for impl_def_id in all_impls {
383 let trait_ref = self.interner.tcx.impl_trait_ref(impl_def_id).unwrap();
384 let self_ty = trait_ref.self_ty();
385 let provides = match (self_ty.kind(), chalk_ty) {
386 (&ty::Adt(impl_adt_def, ..), Adt(id, ..)) => impl_adt_def.did() == id.0.did(),
387 (_, AssociatedType(_ty_id, ..)) => {
388 // FIXME(chalk): See https://github.com/rust-lang/rust/pull/77152#discussion_r494484774
391 (ty::Bool, Scalar(Bool)) => true,
392 (ty::Char, Scalar(Char)) => true,
393 (ty::Int(ty1), Scalar(Int(ty2))) => matches!(
395 (ty::IntTy::Isize, chalk_ir::IntTy::Isize)
396 | (ty::IntTy::I8, chalk_ir::IntTy::I8)
397 | (ty::IntTy::I16, chalk_ir::IntTy::I16)
398 | (ty::IntTy::I32, chalk_ir::IntTy::I32)
399 | (ty::IntTy::I64, chalk_ir::IntTy::I64)
400 | (ty::IntTy::I128, chalk_ir::IntTy::I128)
402 (ty::Uint(ty1), Scalar(Uint(ty2))) => matches!(
404 (ty::UintTy::Usize, chalk_ir::UintTy::Usize)
405 | (ty::UintTy::U8, chalk_ir::UintTy::U8)
406 | (ty::UintTy::U16, chalk_ir::UintTy::U16)
407 | (ty::UintTy::U32, chalk_ir::UintTy::U32)
408 | (ty::UintTy::U64, chalk_ir::UintTy::U64)
409 | (ty::UintTy::U128, chalk_ir::UintTy::U128)
411 (ty::Float(ty1), Scalar(Float(ty2))) => matches!(
413 (ty::FloatTy::F32, chalk_ir::FloatTy::F32)
414 | (ty::FloatTy::F64, chalk_ir::FloatTy::F64)
416 (&ty::Tuple(substs), Tuple(len, _)) => substs.len() == *len,
417 (&ty::Array(..), Array(..)) => true,
418 (&ty::Slice(..), Slice(..)) => true,
419 (&ty::RawPtr(type_and_mut), Raw(mutability, _)) => {
420 match (type_and_mut.mutbl, mutability) {
421 (ast::Mutability::Mut, chalk_ir::Mutability::Mut) => true,
422 (ast::Mutability::Mut, chalk_ir::Mutability::Not) => false,
423 (ast::Mutability::Not, chalk_ir::Mutability::Mut) => false,
424 (ast::Mutability::Not, chalk_ir::Mutability::Not) => true,
427 (&ty::Ref(.., mutability1), Ref(mutability2, ..)) => {
428 match (mutability1, mutability2) {
429 (ast::Mutability::Mut, chalk_ir::Mutability::Mut) => true,
430 (ast::Mutability::Mut, chalk_ir::Mutability::Not) => false,
431 (ast::Mutability::Not, chalk_ir::Mutability::Mut) => false,
432 (ast::Mutability::Not, chalk_ir::Mutability::Not) => true,
436 &ty::Alias(ty::Opaque, ty::AliasTy { def_id, substs: _ }),
437 OpaqueType(opaque_ty_id, ..),
438 ) => def_id == opaque_ty_id.0,
439 (&ty::FnDef(def_id, ..), FnDef(fn_def_id, ..)) => def_id == fn_def_id.0,
440 (&ty::Str, Str) => true,
441 (&ty::Never, Never) => true,
442 (&ty::Closure(def_id, ..), Closure(closure_id, _)) => def_id == closure_id.0,
443 (&ty::Foreign(def_id), Foreign(foreign_def_id)) => def_id == foreign_def_id.0,
444 (&ty::Error(..), Error) => false,
454 fn associated_ty_value(
456 associated_ty_id: chalk_solve::rust_ir::AssociatedTyValueId<RustInterner<'tcx>>,
457 ) -> Arc<chalk_solve::rust_ir::AssociatedTyValue<RustInterner<'tcx>>> {
458 let def_id = associated_ty_id.0;
459 let assoc_item = self.interner.tcx.associated_item(def_id);
460 let impl_id = assoc_item.container_id(self.interner.tcx);
461 match assoc_item.kind {
462 AssocKind::Type => {}
463 _ => unimplemented!("Not possible??"),
466 let trait_item_id = assoc_item.trait_item_def_id.expect("assoc_ty with no trait version");
467 let bound_vars = bound_vars_for_item(self.interner.tcx, def_id);
468 let binders = binders_for(self.interner, bound_vars);
472 .bound_type_of(def_id)
473 .subst(self.interner.tcx, bound_vars)
474 .lower_into(self.interner);
476 Arc::new(chalk_solve::rust_ir::AssociatedTyValue {
477 impl_id: chalk_ir::ImplId(impl_id),
478 associated_ty_id: chalk_ir::AssocTypeId(trait_item_id),
479 value: chalk_ir::Binders::new(
481 chalk_solve::rust_ir::AssociatedTyValueBound { ty },
486 fn custom_clauses(&self) -> Vec<chalk_ir::ProgramClause<RustInterner<'tcx>>> {
490 fn local_impls_to_coherence_check(
492 _trait_id: chalk_ir::TraitId<RustInterner<'tcx>>,
493 ) -> Vec<chalk_ir::ImplId<RustInterner<'tcx>>> {
499 opaque_ty_id: chalk_ir::OpaqueTyId<RustInterner<'tcx>>,
500 ) -> Arc<chalk_solve::rust_ir::OpaqueTyDatum<RustInterner<'tcx>>> {
501 let bound_vars = ty::fold::shift_vars(
503 bound_vars_for_item(self.interner.tcx, opaque_ty_id.0),
506 let where_clauses = self.where_clauses_for(opaque_ty_id.0, bound_vars);
508 let identity_substs = InternalSubsts::identity_for_item(self.interner.tcx, opaque_ty_id.0);
510 let explicit_item_bounds = self.interner.tcx.bound_explicit_item_bounds(opaque_ty_id.0);
516 explicit_item_bounds.rebind(*bound).subst(self.interner.tcx, &bound_vars)
519 bound.fold_with(&mut ReplaceOpaqueTyFolder {
520 tcx: self.interner.tcx,
523 binder_index: ty::INNERMOST,
526 .filter_map(|bound| {
528 Option<chalk_ir::QuantifiedWhereClause<RustInterner<'tcx>>>
529 >::lower_into(bound, self.interner)
533 // Binder for the bound variable representing the concrete impl Trait type.
534 let existential_binder = chalk_ir::VariableKinds::from1(
536 chalk_ir::VariableKind::Ty(chalk_ir::TyVariableKind::General),
539 let value = chalk_solve::rust_ir::OpaqueTyDatumBound {
540 bounds: chalk_ir::Binders::new(existential_binder.clone(), bounds),
541 where_clauses: chalk_ir::Binders::new(existential_binder, where_clauses),
544 let binders = binders_for(self.interner, bound_vars);
545 Arc::new(chalk_solve::rust_ir::OpaqueTyDatum {
547 bound: chalk_ir::Binders::new(binders, value),
551 fn program_clauses_for_env(
553 environment: &chalk_ir::Environment<RustInterner<'tcx>>,
554 ) -> chalk_ir::ProgramClauses<RustInterner<'tcx>> {
555 chalk_solve::program_clauses_for_env(self, environment)
558 fn well_known_trait_id(
560 well_known_trait: chalk_solve::rust_ir::WellKnownTrait,
561 ) -> Option<chalk_ir::TraitId<RustInterner<'tcx>>> {
562 use chalk_solve::rust_ir::WellKnownTrait::*;
563 let lang_items = self.interner.tcx.lang_items();
564 let def_id = match well_known_trait {
565 Sized => lang_items.sized_trait(),
566 Copy => lang_items.copy_trait(),
567 Clone => lang_items.clone_trait(),
568 Drop => lang_items.drop_trait(),
569 Fn => lang_items.fn_trait(),
570 FnMut => lang_items.fn_mut_trait(),
571 FnOnce => lang_items.fn_once_trait(),
572 Generator => lang_items.gen_trait(),
573 Unsize => lang_items.unsize_trait(),
574 Unpin => lang_items.unpin_trait(),
575 CoerceUnsized => lang_items.coerce_unsized_trait(),
576 DiscriminantKind => lang_items.discriminant_kind_trait(),
577 DispatchFromDyn => lang_items.dispatch_from_dyn_trait(),
578 Tuple => lang_items.tuple_trait(),
580 def_id.map(chalk_ir::TraitId)
583 fn is_object_safe(&self, trait_id: chalk_ir::TraitId<RustInterner<'tcx>>) -> bool {
584 self.interner.tcx.is_object_safe(trait_id.0)
587 fn hidden_opaque_type(
589 _id: chalk_ir::OpaqueTyId<RustInterner<'tcx>>,
590 ) -> chalk_ir::Ty<RustInterner<'tcx>> {
591 // FIXME(chalk): actually get hidden ty
594 .mk_ty(ty::Tuple(self.interner.tcx.intern_type_list(&[])))
595 .lower_into(self.interner)
600 _closure_id: chalk_ir::ClosureId<RustInterner<'tcx>>,
601 substs: &chalk_ir::Substitution<RustInterner<'tcx>>,
602 ) -> chalk_solve::rust_ir::ClosureKind {
603 let kind = &substs.as_slice(self.interner)[substs.len(self.interner) - 3];
604 match kind.assert_ty_ref(self.interner).kind(self.interner) {
605 chalk_ir::TyKind::Scalar(chalk_ir::Scalar::Int(int_ty)) => match int_ty {
606 chalk_ir::IntTy::I8 => chalk_solve::rust_ir::ClosureKind::Fn,
607 chalk_ir::IntTy::I16 => chalk_solve::rust_ir::ClosureKind::FnMut,
608 chalk_ir::IntTy::I32 => chalk_solve::rust_ir::ClosureKind::FnOnce,
609 _ => bug!("bad closure kind"),
611 _ => bug!("bad closure kind"),
615 fn closure_inputs_and_output(
617 _closure_id: chalk_ir::ClosureId<RustInterner<'tcx>>,
618 substs: &chalk_ir::Substitution<RustInterner<'tcx>>,
619 ) -> chalk_ir::Binders<chalk_solve::rust_ir::FnDefInputsAndOutputDatum<RustInterner<'tcx>>>
621 let sig = &substs.as_slice(self.interner)[substs.len(self.interner) - 2];
622 match sig.assert_ty_ref(self.interner).kind(self.interner) {
623 chalk_ir::TyKind::Function(f) => {
624 let substitution = f.substitution.0.as_slice(self.interner);
625 let return_type = substitution.last().unwrap().assert_ty_ref(self.interner).clone();
626 // Closure arguments are tupled
627 let argument_tuple = substitution[0].assert_ty_ref(self.interner);
628 let argument_types = match argument_tuple.kind(self.interner) {
629 chalk_ir::TyKind::Tuple(_len, substitution) => substitution
631 .map(|arg| arg.assert_ty_ref(self.interner))
634 _ => bug!("Expecting closure FnSig args to be tupled."),
637 chalk_ir::Binders::new(
638 chalk_ir::VariableKinds::from_iter(
640 (0..f.num_binders).map(|_| chalk_ir::VariableKind::Lifetime),
642 chalk_solve::rust_ir::FnDefInputsAndOutputDatum { argument_types, return_type },
645 _ => panic!("Invalid sig."),
651 _closure_id: chalk_ir::ClosureId<RustInterner<'tcx>>,
652 substs: &chalk_ir::Substitution<RustInterner<'tcx>>,
653 ) -> chalk_ir::Binders<chalk_ir::Ty<RustInterner<'tcx>>> {
654 let inputs_and_output = self.closure_inputs_and_output(_closure_id, substs);
655 let tuple = substs.as_slice(self.interner).last().unwrap().assert_ty_ref(self.interner);
656 inputs_and_output.map_ref(|_| tuple.clone())
659 fn closure_fn_substitution(
661 _closure_id: chalk_ir::ClosureId<RustInterner<'tcx>>,
662 substs: &chalk_ir::Substitution<RustInterner<'tcx>>,
663 ) -> chalk_ir::Substitution<RustInterner<'tcx>> {
664 let substitution = &substs.as_slice(self.interner)[0..substs.len(self.interner) - 3];
665 chalk_ir::Substitution::from_iter(self.interner, substitution)
670 _generator_id: chalk_ir::GeneratorId<RustInterner<'tcx>>,
671 ) -> Arc<chalk_solve::rust_ir::GeneratorDatum<RustInterner<'tcx>>> {
675 fn generator_witness_datum(
677 _generator_id: chalk_ir::GeneratorId<RustInterner<'tcx>>,
678 ) -> Arc<chalk_solve::rust_ir::GeneratorWitnessDatum<RustInterner<'tcx>>> {
682 fn unification_database(&self) -> &dyn chalk_ir::UnificationDatabase<RustInterner<'tcx>> {
686 fn discriminant_type(
688 _: chalk_ir::Ty<RustInterner<'tcx>>,
689 ) -> chalk_ir::Ty<RustInterner<'tcx>> {
694 impl<'tcx> chalk_ir::UnificationDatabase<RustInterner<'tcx>> for RustIrDatabase<'tcx> {
697 def_id: chalk_ir::FnDefId<RustInterner<'tcx>>,
698 ) -> chalk_ir::Variances<RustInterner<'tcx>> {
699 let variances = self.interner.tcx.variances_of(def_id.0);
700 chalk_ir::Variances::from_iter(
702 variances.iter().map(|v| v.lower_into(self.interner)),
708 adt_id: chalk_ir::AdtId<RustInterner<'tcx>>,
709 ) -> chalk_ir::Variances<RustInterner<'tcx>> {
710 let variances = self.interner.tcx.variances_of(adt_id.0.did());
711 chalk_ir::Variances::from_iter(
713 variances.iter().map(|v| v.lower_into(self.interner)),
718 /// Creates an `InternalSubsts` that maps each generic parameter to a higher-ranked
719 /// var bound at index `0`. For types, we use a `BoundVar` index equal to
720 /// the type parameter index. For regions, we use the `BoundRegionKind::BrNamed`
721 /// variant (which has a `DefId`).
722 fn bound_vars_for_item<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> SubstsRef<'tcx> {
723 InternalSubsts::for_item(tcx, def_id, |param, substs| match param.kind {
724 ty::GenericParamDefKind::Type { .. } => tcx
728 var: ty::BoundVar::from(param.index),
729 kind: ty::BoundTyKind::Param(param.name),
734 ty::GenericParamDefKind::Lifetime => {
735 let br = ty::BoundRegion {
736 var: ty::BoundVar::from_usize(substs.len()),
737 kind: ty::BrAnon(substs.len() as u32, None),
739 tcx.mk_region(ty::ReLateBound(ty::INNERMOST, br)).into()
742 ty::GenericParamDefKind::Const { .. } => tcx
744 ty::ConstKind::Bound(ty::INNERMOST, ty::BoundVar::from(param.index)),
745 tcx.type_of(param.def_id),
751 fn binders_for<'tcx>(
752 interner: RustInterner<'tcx>,
753 bound_vars: SubstsRef<'tcx>,
754 ) -> chalk_ir::VariableKinds<RustInterner<'tcx>> {
755 chalk_ir::VariableKinds::from_iter(
757 bound_vars.iter().map(|arg| match arg.unpack() {
758 ty::subst::GenericArgKind::Lifetime(_re) => chalk_ir::VariableKind::Lifetime,
759 ty::subst::GenericArgKind::Type(_ty) => {
760 chalk_ir::VariableKind::Ty(chalk_ir::TyVariableKind::General)
762 ty::subst::GenericArgKind::Const(c) => {
763 chalk_ir::VariableKind::Const(c.ty().lower_into(interner))
769 struct ReplaceOpaqueTyFolder<'tcx> {
771 opaque_ty_id: chalk_ir::OpaqueTyId<RustInterner<'tcx>>,
772 identity_substs: SubstsRef<'tcx>,
773 binder_index: ty::DebruijnIndex,
776 impl<'tcx> ty::TypeFolder<'tcx> for ReplaceOpaqueTyFolder<'tcx> {
777 fn tcx<'b>(&'b self) -> TyCtxt<'tcx> {
781 fn fold_binder<T: TypeFoldable<'tcx>>(
783 t: ty::Binder<'tcx, T>,
784 ) -> ty::Binder<'tcx, T> {
785 self.binder_index.shift_in(1);
786 let t = t.super_fold_with(self);
787 self.binder_index.shift_out(1);
791 fn fold_ty(&mut self, ty: Ty<'tcx>) -> Ty<'tcx> {
792 if let ty::Alias(ty::Opaque, ty::AliasTy { def_id, substs }) = *ty.kind() {
793 if def_id == self.opaque_ty_id.0 && substs == self.identity_substs {
794 return self.tcx.mk_ty(ty::Bound(
796 ty::BoundTy::from(ty::BoundVar::from_u32(0)),