diff options
Diffstat (limited to 'compiler/rustc_middle/src/ty/sty.rs')
| -rw-r--r-- | compiler/rustc_middle/src/ty/sty.rs | 144 |
1 files changed, 107 insertions, 37 deletions
diff --git a/compiler/rustc_middle/src/ty/sty.rs b/compiler/rustc_middle/src/ty/sty.rs index 7bda20ffe9a..e6d51c4ec97 100644 --- a/compiler/rustc_middle/src/ty/sty.rs +++ b/compiler/rustc_middle/src/ty/sty.rs @@ -727,13 +727,13 @@ impl<'tcx> PolyExistentialPredicate<'tcx> { ExistentialPredicate::AutoTrait(did) => { let generics = tcx.generics_of(did); let trait_ref = if generics.params.len() == 1 { - tcx.mk_trait_ref(did, [self_ty]) + ty::TraitRef::new(tcx, did, [self_ty]) } else { // If this is an ill-formed auto trait, then synthesize // new error substs for the missing generics. let err_substs = ty::InternalSubsts::extend_with_error(tcx, did, &[self_ty.into()]); - tcx.mk_trait_ref(did, err_substs) + ty::TraitRef::new(tcx, did, err_substs) }; self.rebind(trait_ref).without_const().to_predicate(tcx) } @@ -820,36 +820,68 @@ pub struct TraitRef<'tcx> { pub def_id: DefId, pub substs: SubstsRef<'tcx>, /// This field exists to prevent the creation of `TraitRef` without - /// calling [TyCtxt::mk_trait_ref]. - pub(super) _use_mk_trait_ref_instead: (), + /// calling [`TraitRef::new`]. + pub(super) _use_trait_ref_new_instead: (), } impl<'tcx> TraitRef<'tcx> { + pub fn new( + tcx: TyCtxt<'tcx>, + trait_def_id: DefId, + substs: impl IntoIterator<Item: Into<GenericArg<'tcx>>>, + ) -> Self { + let substs = tcx.check_and_mk_substs(trait_def_id, substs); + Self { def_id: trait_def_id, substs, _use_trait_ref_new_instead: () } + } + + pub fn from_lang_item( + tcx: TyCtxt<'tcx>, + trait_lang_item: LangItem, + span: Span, + substs: impl IntoIterator<Item: Into<ty::GenericArg<'tcx>>>, + ) -> Self { + let trait_def_id = tcx.require_lang_item(trait_lang_item, Some(span)); + Self::new(tcx, trait_def_id, substs) + } + + pub fn from_method( + tcx: TyCtxt<'tcx>, + trait_id: DefId, + substs: SubstsRef<'tcx>, + ) -> ty::TraitRef<'tcx> { + let defs = tcx.generics_of(trait_id); + ty::TraitRef::new(tcx, trait_id, tcx.mk_substs(&substs[..defs.params.len()])) + } + + /// Returns a `TraitRef` of the form `P0: Foo<P1..Pn>` where `Pi` + /// are the parameters defined on trait. + pub fn identity(tcx: TyCtxt<'tcx>, def_id: DefId) -> TraitRef<'tcx> { + ty::TraitRef::new(tcx, def_id, InternalSubsts::identity_for_item(tcx, def_id)) + } + pub fn with_self_ty(self, tcx: TyCtxt<'tcx>, self_ty: Ty<'tcx>) -> Self { - tcx.mk_trait_ref( + ty::TraitRef::new( + tcx, self.def_id, [self_ty.into()].into_iter().chain(self.substs.iter().skip(1)), ) } - /// Returns a `TraitRef` of the form `P0: Foo<P1..Pn>` where `Pi` - /// are the parameters defined on trait. - pub fn identity(tcx: TyCtxt<'tcx>, def_id: DefId) -> Binder<'tcx, TraitRef<'tcx>> { - ty::Binder::dummy(tcx.mk_trait_ref(def_id, InternalSubsts::identity_for_item(tcx, def_id))) + /// Converts this trait ref to a trait predicate with a given `constness` and a positive polarity. + #[inline] + pub fn with_constness(self, constness: ty::BoundConstness) -> ty::TraitPredicate<'tcx> { + ty::TraitPredicate { trait_ref: self, constness, polarity: ty::ImplPolarity::Positive } } + /// Converts this trait ref to a trait predicate without `const` and a positive polarity. #[inline] - pub fn self_ty(&self) -> Ty<'tcx> { - self.substs.type_at(0) + pub fn without_const(self) -> ty::TraitPredicate<'tcx> { + self.with_constness(ty::BoundConstness::NotConst) } - pub fn from_method( - tcx: TyCtxt<'tcx>, - trait_id: DefId, - substs: SubstsRef<'tcx>, - ) -> ty::TraitRef<'tcx> { - let defs = tcx.generics_of(trait_id); - tcx.mk_trait_ref(trait_id, tcx.mk_substs(&substs[..defs.params.len()])) + #[inline] + pub fn self_ty(&self) -> Ty<'tcx> { + self.substs.type_at(0) } } @@ -907,7 +939,7 @@ impl<'tcx> ExistentialTraitRef<'tcx> { // otherwise the escaping vars would be captured by the binder // debug_assert!(!self_ty.has_escaping_bound_vars()); - tcx.mk_trait_ref(self.def_id, [self_ty.into()].into_iter().chain(self.substs.iter())) + ty::TraitRef::new(tcx, self.def_id, [self_ty.into()].into_iter().chain(self.substs.iter())) } } @@ -1158,9 +1190,9 @@ where /// Represents the projection of an associated type. /// -/// For a projection, this would be `<Ty as Trait<...>>::N`. -/// -/// For an opaque type, there is no explicit syntax. +/// * For a projection, this would be `<Ty as Trait<...>>::N<...>`. +/// * For an inherent projection, this would be `Ty::N<...>`. +/// * For an opaque type, there is no explicit syntax. #[derive(Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash, TyEncodable, TyDecodable)] #[derive(HashStable, TypeFoldable, TypeVisitable, Lift)] pub struct AliasTy<'tcx> { @@ -1169,12 +1201,16 @@ pub struct AliasTy<'tcx> { /// For a projection, these are the substitutions for the trait and the /// GAT substitutions, if there are any. /// + /// For an inherent projection, they consist of the self type and the GAT substitutions, + /// if there are any. + /// /// For RPIT the substitutions are for the generics of the function, /// while for TAIT it is used for the generic parameters of the alias. pub substs: SubstsRef<'tcx>, - /// The `DefId` of the `TraitItem` for the associated type `N` if this is a projection, - /// or the `OpaqueType` item if this is an opaque. + /// The `DefId` of the `TraitItem` or `ImplItem` for the associated type `N` depending on whether + /// this is a projection or an inherent projection or the `DefId` of the `OpaqueType` item if + /// this is an opaque. /// /// During codegen, `tcx.type_of(def_id)` can be used to get the type of the /// underlying type if the type is an opaque. @@ -1192,6 +1228,7 @@ pub struct AliasTy<'tcx> { impl<'tcx> AliasTy<'tcx> { pub fn kind(self, tcx: TyCtxt<'tcx>) -> ty::AliasKind { match tcx.def_kind(self.def_id) { + DefKind::AssocTy if let DefKind::Impl { of_trait: false } = tcx.def_kind(tcx.parent(self.def_id)) => ty::Inherent, DefKind::AssocTy | DefKind::ImplTraitPlaceholder => ty::Projection, DefKind::OpaqueTy => ty::Opaque, kind => bug!("unexpected DefKind in AliasTy: {kind:?}"), @@ -1205,6 +1242,17 @@ impl<'tcx> AliasTy<'tcx> { /// The following methods work only with associated type projections. impl<'tcx> AliasTy<'tcx> { + pub fn self_ty(self) -> Ty<'tcx> { + self.substs.type_at(0) + } + + pub fn with_self_ty(self, tcx: TyCtxt<'tcx>, self_ty: Ty<'tcx>) -> Self { + tcx.mk_alias_ty(self.def_id, [self_ty.into()].into_iter().chain(self.substs.iter().skip(1))) + } +} + +/// The following methods work only with trait associated type projections. +impl<'tcx> AliasTy<'tcx> { pub fn trait_def_id(self, tcx: TyCtxt<'tcx>) -> DefId { match tcx.def_kind(self.def_id) { DefKind::AssocTy | DefKind::AssocConst => tcx.parent(self.def_id), @@ -1217,7 +1265,7 @@ impl<'tcx> AliasTy<'tcx> { /// Extracts the underlying trait reference and own substs from this projection. /// For example, if this is a projection of `<T as StreamingIterator>::Item<'a>`, - /// then this function would return a `T: Iterator` trait reference and `['a]` as the own substs + /// then this function would return a `T: StreamingIterator` trait reference and `['a]` as the own substs pub fn trait_ref_and_own_substs( self, tcx: TyCtxt<'tcx>, @@ -1226,7 +1274,7 @@ impl<'tcx> AliasTy<'tcx> { let trait_def_id = self.trait_def_id(tcx); let trait_generics = tcx.generics_of(trait_def_id); ( - tcx.mk_trait_ref(trait_def_id, self.substs.truncate_to(tcx, trait_generics)), + ty::TraitRef::new(tcx, trait_def_id, self.substs.truncate_to(tcx, trait_generics)), &self.substs[trait_generics.count()..], ) } @@ -1240,15 +1288,30 @@ impl<'tcx> AliasTy<'tcx> { /// as well. pub fn trait_ref(self, tcx: TyCtxt<'tcx>) -> ty::TraitRef<'tcx> { let def_id = self.trait_def_id(tcx); - tcx.mk_trait_ref(def_id, self.substs.truncate_to(tcx, tcx.generics_of(def_id))) + ty::TraitRef::new(tcx, def_id, self.substs.truncate_to(tcx, tcx.generics_of(def_id))) } +} - pub fn self_ty(self) -> Ty<'tcx> { - self.substs.type_at(0) - } +/// The following methods work only with inherent associated type projections. +impl<'tcx> AliasTy<'tcx> { + /// Transform the substitutions to have the given `impl` substs as the base and the GAT substs on top of that. + /// + /// Does the following transformation: + /// + /// ```text + /// [Self, P_0...P_m] -> [I_0...I_n, P_0...P_m] + /// + /// I_i impl subst + /// P_j GAT subst + /// ``` + pub fn rebase_substs_onto_impl( + self, + impl_substs: ty::SubstsRef<'tcx>, + tcx: TyCtxt<'tcx>, + ) -> ty::SubstsRef<'tcx> { + debug_assert_eq!(self.kind(tcx), ty::Inherent); - pub fn with_self_ty(self, tcx: TyCtxt<'tcx>, self_ty: Ty<'tcx>) -> Self { - tcx.mk_alias_ty(self.def_id, [self_ty.into()].into_iter().chain(self.substs.iter().skip(1))) + tcx.mk_substs_from_iter(impl_substs.into_iter().chain(self.substs.into_iter().skip(1))) } } @@ -1645,7 +1708,9 @@ impl<'tcx> Region<'tcx> { ty::ReErased => { flags = flags | TypeFlags::HAS_RE_ERASED; } - ty::ReError(_) => {} + ty::ReError(_) => { + flags = flags | TypeFlags::HAS_FREE_REGIONS; + } } debug!("type_flags({:?}) = {:?}", self, flags); @@ -2303,13 +2368,11 @@ impl<'tcx> Ty<'tcx> { ty::Adt(def, _substs) => def.sized_constraint(tcx).0.is_empty(), - ty::Alias(..) | ty::Param(_) => false, + ty::Alias(..) | ty::Param(_) | ty::Placeholder(..) => false, ty::Infer(ty::TyVar(_)) => false, - ty::Bound(..) - | ty::Placeholder(..) - | ty::Infer(ty::FreshTy(_) | ty::FreshIntTy(_) | ty::FreshFloatTy(_)) => { + ty::Bound(..) | ty::Infer(ty::FreshTy(_) | ty::FreshIntTy(_) | ty::FreshFloatTy(_)) => { bug!("`is_trivially_sized` applied to unexpected type: {:?}", self) } } @@ -2400,6 +2463,13 @@ impl<'tcx> Ty<'tcx> { _ => None, } } + + pub fn is_c_void(self, tcx: TyCtxt<'_>) -> bool { + match self.kind() { + ty::Adt(adt, _) => tcx.lang_items().get(LangItem::CVoid) == Some(adt.did()), + _ => false, + } + } } /// Extra information about why we ended up with a particular variance. |