diff options
Diffstat (limited to 'compiler/rustc_middle/src/ty/mod.rs')
| -rw-r--r-- | compiler/rustc_middle/src/ty/mod.rs | 500 |
1 files changed, 297 insertions, 203 deletions
diff --git a/compiler/rustc_middle/src/ty/mod.rs b/compiler/rustc_middle/src/ty/mod.rs index 72341e656e2..f9c0fbb23c3 100644 --- a/compiler/rustc_middle/src/ty/mod.rs +++ b/compiler/rustc_middle/src/ty/mod.rs @@ -28,6 +28,7 @@ use crate::ty::fast_reject::SimplifiedType; use crate::ty::util::Discr; pub use adt::*; pub use assoc::*; +pub use generic_args::*; pub use generics::*; use rustc_ast as ast; use rustc_ast::node_id::NodeMap; @@ -53,7 +54,7 @@ use rustc_span::symbol::{kw, sym, Ident, Symbol}; use rustc_span::{ExpnId, ExpnKind, Span}; use rustc_target::abi::{Align, FieldIdx, Integer, IntegerType, VariantIdx}; pub use rustc_target::abi::{ReprFlags, ReprOptions}; -pub use subst::*; +pub use rustc_type_ir::{DebugWithInfcx, InferCtxtLike, OptWithInfcx}; pub use vtable::*; use std::fmt::Debug; @@ -66,6 +67,10 @@ use std::{fmt, str}; pub use crate::ty::diagnostics::*; pub use rustc_type_ir::AliasKind::*; +pub use rustc_type_ir::ConstKind::{ + Bound as BoundCt, Error as ErrorCt, Expr as ExprCt, Infer as InferCt, Param as ParamCt, + Placeholder as PlaceholderCt, Unevaluated, Value, +}; pub use rustc_type_ir::DynKind::*; pub use rustc_type_ir::InferTy::*; pub use rustc_type_ir::RegionKind::*; @@ -77,11 +82,10 @@ pub use self::binding::BindingMode::*; pub use self::closure::{ is_ancestor_or_same_capture, place_to_string_for_capture, BorrowKind, CaptureInfo, CapturedPlace, ClosureKind, ClosureTypeInfo, MinCaptureInformationMap, MinCaptureList, - RootVariableMinCaptureList, UpvarCapture, UpvarCaptureMap, UpvarId, UpvarListMap, UpvarPath, - CAPTURE_STRUCT_LOCAL, + RootVariableMinCaptureList, UpvarCapture, UpvarId, UpvarPath, CAPTURE_STRUCT_LOCAL, }; pub use self::consts::{ - Const, ConstData, ConstInt, ConstKind, Expr, InferConst, ScalarInt, UnevaluatedConst, ValTree, + Const, ConstData, ConstInt, Expr, InferConst, ScalarInt, UnevaluatedConst, ValTree, }; pub use self::context::{ tls, CtxtInterners, DeducedParamAttrs, FreeRegionInfo, GlobalCtxt, Lift, TyCtxt, TyCtxtFeed, @@ -93,12 +97,12 @@ pub use self::rvalue_scopes::RvalueScopes; pub use self::sty::BoundRegionKind::*; pub use self::sty::{ AliasTy, Article, Binder, BoundRegion, BoundRegionKind, BoundTy, BoundTyKind, BoundVar, - BoundVariableKind, CanonicalPolyFnSig, ClosureSubsts, ClosureSubstsParts, ConstVid, + BoundVariableKind, CanonicalPolyFnSig, ClosureArgs, ClosureArgsParts, ConstKind, ConstVid, EarlyBoundRegion, ExistentialPredicate, ExistentialProjection, ExistentialTraitRef, FnSig, - FreeRegion, GenSig, GeneratorSubsts, GeneratorSubstsParts, InlineConstSubsts, - InlineConstSubstsParts, ParamConst, ParamTy, PolyExistentialPredicate, - PolyExistentialProjection, PolyExistentialTraitRef, PolyFnSig, PolyGenSig, PolyTraitRef, - Region, RegionKind, RegionVid, TraitRef, TyKind, TypeAndMut, UpvarSubsts, VarianceDiagInfo, + FreeRegion, GenSig, GeneratorArgs, GeneratorArgsParts, InlineConstArgs, InlineConstArgsParts, + ParamConst, ParamTy, PolyExistentialPredicate, PolyExistentialProjection, + PolyExistentialTraitRef, PolyFnSig, PolyGenSig, PolyTraitRef, Region, RegionKind, RegionVid, + TraitRef, TyKind, TypeAndMut, UpvarArgs, VarianceDiagInfo, }; pub use self::trait_def::TraitDef; pub use self::typeck_results::{ @@ -122,7 +126,6 @@ pub mod layout; pub mod normalize_erasing_regions; pub mod print; pub mod relate; -pub mod subst; pub mod trait_def; pub mod util; pub mod visit; @@ -136,6 +139,7 @@ mod consts; mod context; mod diagnostics; mod erase_regions; +mod generic_args; mod generics; mod impls_ty; mod instance; @@ -144,7 +148,7 @@ mod opaque_types; mod parameterized; mod rvalue_scopes; mod structural_impls; -#[cfg_attr(not(bootstrap), allow(hidden_glob_reexports))] +#[allow(hidden_glob_reexports)] mod sty; mod typeck_results; @@ -456,6 +460,11 @@ impl ty::EarlyBoundRegion { } } +/// A statement that can be proven by a trait solver. This includes things that may +/// show up in where clauses, such as trait predicates and projection predicates, +/// and also things that are emitted as part of type checking such as `ObjectSafe` +/// predicate which is emitted when a type is coerced to a trait object. +/// /// Use this rather than `PredicateKind`, whenever possible. #[derive(Clone, Copy, PartialEq, Eq, Hash, HashStable)] #[rustc_pass_by_value] @@ -487,11 +496,11 @@ impl<'tcx> Predicate<'tcx> { let kind = self .kind() .map_bound(|kind| match kind { - PredicateKind::Clause(Clause::Trait(TraitPredicate { + PredicateKind::Clause(ClauseKind::Trait(TraitPredicate { trait_ref, constness, polarity, - })) => Some(PredicateKind::Clause(Clause::Trait(TraitPredicate { + })) => Some(PredicateKind::Clause(ClauseKind::Trait(TraitPredicate { trait_ref, constness, polarity: polarity.flip()?, @@ -505,10 +514,10 @@ impl<'tcx> Predicate<'tcx> { } pub fn without_const(mut self, tcx: TyCtxt<'tcx>) -> Self { - if let PredicateKind::Clause(Clause::Trait(TraitPredicate { trait_ref, constness, polarity })) = self.kind().skip_binder() + if let PredicateKind::Clause(ClauseKind::Trait(TraitPredicate { trait_ref, constness, polarity })) = self.kind().skip_binder() && constness != BoundConstness::NotConst { - self = tcx.mk_predicate(self.kind().rebind(PredicateKind::Clause(Clause::Trait(TraitPredicate { + self = tcx.mk_predicate(self.kind().rebind(PredicateKind::Clause(ClauseKind::Trait(TraitPredicate { trait_ref, constness: BoundConstness::NotConst, polarity, @@ -520,10 +529,10 @@ impl<'tcx> Predicate<'tcx> { #[instrument(level = "debug", skip(tcx), ret)] pub fn is_coinductive(self, tcx: TyCtxt<'tcx>) -> bool { match self.kind().skip_binder() { - ty::PredicateKind::Clause(ty::Clause::Trait(data)) => { + ty::PredicateKind::Clause(ty::ClauseKind::Trait(data)) => { tcx.trait_is_coinductive(data.def_id()) } - ty::PredicateKind::WellFormed(_) => true, + ty::PredicateKind::Clause(ty::ClauseKind::WellFormed(_)) => true, _ => false, } } @@ -536,21 +545,20 @@ impl<'tcx> Predicate<'tcx> { #[inline] pub fn allow_normalization(self) -> bool { match self.kind().skip_binder() { - PredicateKind::WellFormed(_) => false, - PredicateKind::Clause(Clause::Trait(_)) - | PredicateKind::Clause(Clause::RegionOutlives(_)) - | PredicateKind::Clause(Clause::TypeOutlives(_)) - | PredicateKind::Clause(Clause::Projection(_)) - | PredicateKind::Clause(Clause::ConstArgHasType(..)) + PredicateKind::Clause(ClauseKind::WellFormed(_)) => false, + PredicateKind::Clause(ClauseKind::Trait(_)) + | PredicateKind::Clause(ClauseKind::RegionOutlives(_)) + | PredicateKind::Clause(ClauseKind::TypeOutlives(_)) + | PredicateKind::Clause(ClauseKind::Projection(_)) + | PredicateKind::Clause(ClauseKind::ConstArgHasType(..)) | PredicateKind::AliasRelate(..) | PredicateKind::ObjectSafe(_) | PredicateKind::ClosureKind(_, _, _) | PredicateKind::Subtype(_) | PredicateKind::Coerce(_) - | PredicateKind::ConstEvaluatable(_) + | PredicateKind::Clause(ClauseKind::ConstEvaluatable(_)) | PredicateKind::ConstEquate(_, _) - | PredicateKind::Ambiguous - | PredicateKind::TypeWellFormedFromEnv(_) => true, + | PredicateKind::Ambiguous => true, } } } @@ -561,11 +569,77 @@ impl rustc_errors::IntoDiagnosticArg for Predicate<'_> { } } +impl rustc_errors::IntoDiagnosticArg for Clause<'_> { + fn into_diagnostic_arg(self) -> rustc_errors::DiagnosticArgValue<'static> { + rustc_errors::DiagnosticArgValue::Str(std::borrow::Cow::Owned(self.to_string())) + } +} + +/// A subset of predicates which can be assumed by the trait solver. They show up in +/// an item's where clauses, hence the name `Clause`, and may either be user-written +/// (such as traits) or may be inserted during lowering. +#[derive(Clone, Copy, PartialEq, Eq, Hash, HashStable)] +#[rustc_pass_by_value] +pub struct Clause<'tcx>(Interned<'tcx, WithCachedTypeInfo<ty::Binder<'tcx, PredicateKind<'tcx>>>>); + +impl<'tcx> Clause<'tcx> { + pub fn as_predicate(self) -> Predicate<'tcx> { + Predicate(self.0) + } + + pub fn kind(self) -> Binder<'tcx, ClauseKind<'tcx>> { + self.0.internee.map_bound(|kind| match kind { + PredicateKind::Clause(clause) => clause, + _ => unreachable!(), + }) + } + + pub fn as_trait_clause(self) -> Option<Binder<'tcx, TraitPredicate<'tcx>>> { + let clause = self.kind(); + if let ty::ClauseKind::Trait(trait_clause) = clause.skip_binder() { + Some(clause.rebind(trait_clause)) + } else { + None + } + } + + pub fn as_projection_clause(self) -> Option<Binder<'tcx, ProjectionPredicate<'tcx>>> { + let clause = self.kind(); + if let ty::ClauseKind::Projection(projection_clause) = clause.skip_binder() { + Some(clause.rebind(projection_clause)) + } else { + None + } + } + + pub fn as_type_outlives_clause(self) -> Option<Binder<'tcx, TypeOutlivesPredicate<'tcx>>> { + let clause = self.kind(); + if let ty::ClauseKind::TypeOutlives(o) = clause.skip_binder() { + Some(clause.rebind(o)) + } else { + None + } + } + + pub fn as_region_outlives_clause(self) -> Option<Binder<'tcx, RegionOutlivesPredicate<'tcx>>> { + let clause = self.kind(); + if let ty::ClauseKind::RegionOutlives(o) = clause.skip_binder() { + Some(clause.rebind(o)) + } else { + None + } + } + + pub fn without_const(self, tcx: TyCtxt<'tcx>) -> Clause<'tcx> { + self.as_predicate().without_const(tcx).expect_clause() + } +} + #[derive(Clone, Copy, PartialEq, Eq, Hash, TyEncodable, TyDecodable)] #[derive(HashStable, TypeFoldable, TypeVisitable, Lift)] /// A clause is something that can appear in where bounds or be inferred /// by implied bounds. -pub enum Clause<'tcx> { +pub enum ClauseKind<'tcx> { /// Corresponds to `where Foo: Bar<A, B, C>`. `Foo` here would be /// the `Self` type of the trait reference and `A`, `B`, and `C` /// would be the type parameters. @@ -584,24 +658,27 @@ pub enum Clause<'tcx> { /// Ensures that a const generic argument to a parameter `const N: u8` /// is of type `u8`. ConstArgHasType(Const<'tcx>, Ty<'tcx>), + + /// No syntax: `T` well-formed. + WellFormed(GenericArg<'tcx>), + + /// Constant initializer must evaluate successfully. + ConstEvaluatable(ty::Const<'tcx>), } #[derive(Clone, Copy, PartialEq, Eq, Hash, TyEncodable, TyDecodable)] #[derive(HashStable, TypeFoldable, TypeVisitable, Lift)] pub enum PredicateKind<'tcx> { /// Prove a clause - Clause(Clause<'tcx>), - - /// No syntax: `T` well-formed. - WellFormed(GenericArg<'tcx>), + Clause(ClauseKind<'tcx>), /// Trait must be object-safe. ObjectSafe(DefId), /// No direct syntax. May be thought of as `where T: FnFoo<...>` - /// for some substitutions `...` and `T` being a closure type. + /// for some generic args `...` and `T` being a closure type. /// Satisfied (or refuted) once we know the closure's kind. - ClosureKind(DefId, SubstsRef<'tcx>, ClosureKind), + ClosureKind(DefId, GenericArgsRef<'tcx>, ClosureKind), /// `T1 <: T2` /// @@ -620,22 +697,14 @@ pub enum PredicateKind<'tcx> { /// logic. Coerce(CoercePredicate<'tcx>), - /// Constant initializer must evaluate successfully. - ConstEvaluatable(ty::Const<'tcx>), - /// Constants must be equal. The first component is the const that is expected. ConstEquate(Const<'tcx>, Const<'tcx>), - /// Represents a type found in the environment that we can use for implied bounds. - /// - /// Only used for Chalk. - TypeWellFormedFromEnv(Ty<'tcx>), - /// A marker predicate that is always ambiguous. /// Used for coherence to mark opaque types as possibly equal to each other but ambiguous. Ambiguous, - /// Separate from `Clause::Projection` which is used for normalization in new solver. + /// Separate from `ClauseKind::Projection` which is used for normalization in new solver. /// This predicate requires two terms to be equal to eachother. /// /// Only used for new solver @@ -672,7 +741,7 @@ pub struct CratePredicatesMap<'tcx> { pub predicates: FxHashMap<DefId, &'tcx [(Clause<'tcx>, Span)]>, } -impl<'tcx> Predicate<'tcx> { +impl<'tcx> Clause<'tcx> { /// Performs a substitution suitable for going from a /// poly-trait-ref to supertraits that must hold if that /// poly-trait-ref holds. This is slightly different from a normal @@ -682,7 +751,7 @@ impl<'tcx> Predicate<'tcx> { self, tcx: TyCtxt<'tcx>, trait_ref: &ty::PolyTraitRef<'tcx>, - ) -> Predicate<'tcx> { + ) -> Clause<'tcx> { // The interaction between HRTB and supertraits is not entirely // obvious. Let me walk you (and myself) through an example. // @@ -744,15 +813,15 @@ impl<'tcx> Predicate<'tcx> { // this trick achieves that). // Working through the second example: - // trait_ref: for<'x> T: Foo1<'^0.0>; substs: [T, '^0.0] - // predicate: for<'b> Self: Bar1<'a, '^0.0>; substs: [Self, 'a, '^0.0] + // trait_ref: for<'x> T: Foo1<'^0.0>; args: [T, '^0.0] + // predicate: for<'b> Self: Bar1<'a, '^0.0>; args: [Self, 'a, '^0.0] // We want to end up with: // for<'x, 'b> T: Bar1<'^0.0, '^0.1> // To do this: // 1) We must shift all bound vars in predicate by the length // of trait ref's bound vars. So, we would end up with predicate like // Self: Bar1<'a, '^0.1> - // 2) We can then apply the trait substs to this, ending up with + // 2) We can then apply the trait args to this, ending up with // T: Bar1<'^0.0, '^0.1> // 3) Finally, to create the final bound vars, we concatenate the bound // vars of the trait ref with those of the predicate: @@ -764,11 +833,17 @@ impl<'tcx> Predicate<'tcx> { let shifted_pred = tcx.shift_bound_var_indices(trait_bound_vars.len(), bound_pred.skip_binder()); // 2) Self: Bar1<'a, '^0.1> -> T: Bar1<'^0.0, '^0.1> - let new = EarlyBinder::bind(shifted_pred).subst(tcx, trait_ref.skip_binder().substs); + let new = EarlyBinder::bind(shifted_pred).instantiate(tcx, trait_ref.skip_binder().args); // 3) ['x] + ['b] -> ['x, 'b] let bound_vars = tcx.mk_bound_variable_kinds_from_iter(trait_bound_vars.iter().chain(pred_bound_vars)); - tcx.reuse_or_mk_predicate(self, ty::Binder::bind_with_vars(new, bound_vars)) + + // FIXME: Is it really perf sensitive to use reuse_or_mk_predicate here? + tcx.reuse_or_mk_predicate( + self.as_predicate(), + ty::Binder::bind_with_vars(PredicateKind::Clause(new), bound_vars), + ) + .expect_clause() } } @@ -792,20 +867,6 @@ pub struct TraitPredicate<'tcx> { pub type PolyTraitPredicate<'tcx> = ty::Binder<'tcx, TraitPredicate<'tcx>>; impl<'tcx> TraitPredicate<'tcx> { - pub fn remap_constness(&mut self, param_env: &mut ParamEnv<'tcx>) { - *param_env = param_env.with_constness(self.constness.and(param_env.constness())) - } - - /// Remap the constness of this predicate before emitting it for diagnostics. - pub fn remap_constness_diag(&mut self, param_env: ParamEnv<'tcx>) { - // this is different to `remap_constness` that callees want to print this predicate - // in case of selection errors. `T: ~const Drop` bounds cannot end up here when the - // param_env is not const because it is always satisfied in non-const contexts. - if let hir::Constness::NotConst = param_env.constness() { - self.constness = ty::BoundConstness::NotConst; - } - } - pub fn with_self_ty(self, tcx: TyCtxt<'tcx>, self_ty: Ty<'tcx>) -> Self { Self { trait_ref: self.trait_ref.with_self_ty(tcx, self_ty), ..self } } @@ -847,14 +908,6 @@ impl<'tcx> PolyTraitPredicate<'tcx> { self.map_bound(|trait_ref| trait_ref.self_ty()) } - /// Remap the constness of this predicate before emitting it for diagnostics. - pub fn remap_constness_diag(&mut self, param_env: ParamEnv<'tcx>) { - *self = self.map_bound(|mut p| { - p.remap_constness_diag(param_env); - p - }); - } - #[inline] pub fn is_const_if_const(self) -> bool { self.skip_binder().is_const_if_const() @@ -1004,7 +1057,7 @@ impl<'tcx> Term<'tcx> { _ => None, }, TermKind::Const(ct) => match ct.kind() { - ConstKind::Unevaluated(uv) => Some(tcx.mk_alias_ty(uv.def, uv.substs)), + ConstKind::Unevaluated(uv) => Some(tcx.mk_alias_ty(uv.def, uv.args)), _ => None, }, } @@ -1189,13 +1242,41 @@ impl<'tcx> ToPredicate<'tcx> for Binder<'tcx, PredicateKind<'tcx>> { } } -impl<'tcx> ToPredicate<'tcx> for Clause<'tcx> { +impl<'tcx> ToPredicate<'tcx> for ClauseKind<'tcx> { #[inline(always)] fn to_predicate(self, tcx: TyCtxt<'tcx>) -> Predicate<'tcx> { tcx.mk_predicate(ty::Binder::dummy(ty::PredicateKind::Clause(self))) } } +impl<'tcx> ToPredicate<'tcx> for Binder<'tcx, ClauseKind<'tcx>> { + #[inline(always)] + fn to_predicate(self, tcx: TyCtxt<'tcx>) -> Predicate<'tcx> { + tcx.mk_predicate(self.map_bound(ty::PredicateKind::Clause)) + } +} + +impl<'tcx> ToPredicate<'tcx> for Clause<'tcx> { + #[inline(always)] + fn to_predicate(self, _tcx: TyCtxt<'tcx>) -> Predicate<'tcx> { + self.as_predicate() + } +} + +impl<'tcx> ToPredicate<'tcx, Clause<'tcx>> for ClauseKind<'tcx> { + #[inline(always)] + fn to_predicate(self, tcx: TyCtxt<'tcx>) -> Clause<'tcx> { + tcx.mk_predicate(Binder::dummy(ty::PredicateKind::Clause(self))).expect_clause() + } +} + +impl<'tcx> ToPredicate<'tcx, Clause<'tcx>> for Binder<'tcx, ClauseKind<'tcx>> { + #[inline(always)] + fn to_predicate(self, tcx: TyCtxt<'tcx>) -> Clause<'tcx> { + tcx.mk_predicate(self.map_bound(|clause| ty::PredicateKind::Clause(clause))).expect_clause() + } +} + impl<'tcx> ToPredicate<'tcx> for TraitRef<'tcx> { #[inline(always)] fn to_predicate(self, tcx: TyCtxt<'tcx>) -> Predicate<'tcx> { @@ -1203,6 +1284,29 @@ impl<'tcx> ToPredicate<'tcx> for TraitRef<'tcx> { } } +impl<'tcx> ToPredicate<'tcx, TraitPredicate<'tcx>> for TraitRef<'tcx> { + #[inline(always)] + fn to_predicate(self, _tcx: TyCtxt<'tcx>) -> TraitPredicate<'tcx> { + self.without_const() + } +} + +impl<'tcx> ToPredicate<'tcx, Clause<'tcx>> for TraitRef<'tcx> { + #[inline(always)] + fn to_predicate(self, tcx: TyCtxt<'tcx>) -> Clause<'tcx> { + let p: Predicate<'tcx> = self.to_predicate(tcx); + p.expect_clause() + } +} + +impl<'tcx> ToPredicate<'tcx, Clause<'tcx>> for TraitPredicate<'tcx> { + #[inline(always)] + fn to_predicate(self, tcx: TyCtxt<'tcx>) -> Clause<'tcx> { + let p: Predicate<'tcx> = self.to_predicate(tcx); + p.expect_clause() + } +} + impl<'tcx> ToPredicate<'tcx> for Binder<'tcx, TraitRef<'tcx>> { #[inline(always)] fn to_predicate(self, tcx: TyCtxt<'tcx>) -> Predicate<'tcx> { @@ -1211,6 +1315,14 @@ impl<'tcx> ToPredicate<'tcx> for Binder<'tcx, TraitRef<'tcx>> { } } +impl<'tcx> ToPredicate<'tcx, Clause<'tcx>> for Binder<'tcx, TraitRef<'tcx>> { + #[inline(always)] + fn to_predicate(self, tcx: TyCtxt<'tcx>) -> Clause<'tcx> { + let pred: PolyTraitPredicate<'tcx> = self.to_predicate(tcx); + pred.to_predicate(tcx) + } +} + impl<'tcx> ToPredicate<'tcx, PolyTraitPredicate<'tcx>> for Binder<'tcx, TraitRef<'tcx>> { #[inline(always)] fn to_predicate(self, _: TyCtxt<'tcx>) -> PolyTraitPredicate<'tcx> { @@ -1236,31 +1348,45 @@ impl<'tcx> ToPredicate<'tcx, PolyTraitPredicate<'tcx>> for TraitPredicate<'tcx> impl<'tcx> ToPredicate<'tcx> for PolyTraitPredicate<'tcx> { fn to_predicate(self, tcx: TyCtxt<'tcx>) -> Predicate<'tcx> { - self.map_bound(|p| PredicateKind::Clause(Clause::Trait(p))).to_predicate(tcx) + self.map_bound(|p| PredicateKind::Clause(ClauseKind::Trait(p))).to_predicate(tcx) + } +} + +impl<'tcx> ToPredicate<'tcx, Clause<'tcx>> for PolyTraitPredicate<'tcx> { + fn to_predicate(self, tcx: TyCtxt<'tcx>) -> Clause<'tcx> { + let p: Predicate<'tcx> = self.to_predicate(tcx); + p.expect_clause() } } impl<'tcx> ToPredicate<'tcx> for PolyRegionOutlivesPredicate<'tcx> { fn to_predicate(self, tcx: TyCtxt<'tcx>) -> Predicate<'tcx> { - self.map_bound(|p| PredicateKind::Clause(Clause::RegionOutlives(p))).to_predicate(tcx) + self.map_bound(|p| PredicateKind::Clause(ClauseKind::RegionOutlives(p))).to_predicate(tcx) } } impl<'tcx> ToPredicate<'tcx> for PolyTypeOutlivesPredicate<'tcx> { fn to_predicate(self, tcx: TyCtxt<'tcx>) -> Predicate<'tcx> { - self.map_bound(|p| PredicateKind::Clause(Clause::TypeOutlives(p))).to_predicate(tcx) + self.map_bound(|p| PredicateKind::Clause(ClauseKind::TypeOutlives(p))).to_predicate(tcx) } } impl<'tcx> ToPredicate<'tcx> for PolyProjectionPredicate<'tcx> { fn to_predicate(self, tcx: TyCtxt<'tcx>) -> Predicate<'tcx> { - self.map_bound(|p| PredicateKind::Clause(Clause::Projection(p))).to_predicate(tcx) + self.map_bound(|p| PredicateKind::Clause(ClauseKind::Projection(p))).to_predicate(tcx) + } +} + +impl<'tcx> ToPredicate<'tcx, Clause<'tcx>> for PolyProjectionPredicate<'tcx> { + fn to_predicate(self, tcx: TyCtxt<'tcx>) -> Clause<'tcx> { + let p: Predicate<'tcx> = self.to_predicate(tcx); + p.expect_clause() } } impl<'tcx> ToPredicate<'tcx> for TraitPredicate<'tcx> { fn to_predicate(self, tcx: TyCtxt<'tcx>) -> Predicate<'tcx> { - PredicateKind::Clause(Clause::Trait(self)).to_predicate(tcx) + PredicateKind::Clause(ClauseKind::Trait(self)).to_predicate(tcx) } } @@ -1268,63 +1394,76 @@ impl<'tcx> Predicate<'tcx> { pub fn to_opt_poly_trait_pred(self) -> Option<PolyTraitPredicate<'tcx>> { let predicate = self.kind(); match predicate.skip_binder() { - PredicateKind::Clause(Clause::Trait(t)) => Some(predicate.rebind(t)), - PredicateKind::Clause(Clause::Projection(..)) - | PredicateKind::Clause(Clause::ConstArgHasType(..)) + PredicateKind::Clause(ClauseKind::Trait(t)) => Some(predicate.rebind(t)), + PredicateKind::Clause(ClauseKind::Projection(..)) + | PredicateKind::Clause(ClauseKind::ConstArgHasType(..)) | PredicateKind::AliasRelate(..) | PredicateKind::Subtype(..) | PredicateKind::Coerce(..) - | PredicateKind::Clause(Clause::RegionOutlives(..)) - | PredicateKind::WellFormed(..) + | PredicateKind::Clause(ClauseKind::RegionOutlives(..)) + | PredicateKind::Clause(ClauseKind::WellFormed(..)) | PredicateKind::ObjectSafe(..) | PredicateKind::ClosureKind(..) - | PredicateKind::Clause(Clause::TypeOutlives(..)) - | PredicateKind::ConstEvaluatable(..) + | PredicateKind::Clause(ClauseKind::TypeOutlives(..)) + | PredicateKind::Clause(ClauseKind::ConstEvaluatable(..)) | PredicateKind::ConstEquate(..) - | PredicateKind::Ambiguous - | PredicateKind::TypeWellFormedFromEnv(..) => None, + | PredicateKind::Ambiguous => None, } } pub fn to_opt_poly_projection_pred(self) -> Option<PolyProjectionPredicate<'tcx>> { let predicate = self.kind(); match predicate.skip_binder() { - PredicateKind::Clause(Clause::Projection(t)) => Some(predicate.rebind(t)), - PredicateKind::Clause(Clause::Trait(..)) - | PredicateKind::Clause(Clause::ConstArgHasType(..)) + PredicateKind::Clause(ClauseKind::Projection(t)) => Some(predicate.rebind(t)), + PredicateKind::Clause(ClauseKind::Trait(..)) + | PredicateKind::Clause(ClauseKind::ConstArgHasType(..)) | PredicateKind::AliasRelate(..) | PredicateKind::Subtype(..) | PredicateKind::Coerce(..) - | PredicateKind::Clause(Clause::RegionOutlives(..)) - | PredicateKind::WellFormed(..) + | PredicateKind::Clause(ClauseKind::RegionOutlives(..)) + | PredicateKind::Clause(ClauseKind::WellFormed(..)) | PredicateKind::ObjectSafe(..) | PredicateKind::ClosureKind(..) - | PredicateKind::Clause(Clause::TypeOutlives(..)) - | PredicateKind::ConstEvaluatable(..) + | PredicateKind::Clause(ClauseKind::TypeOutlives(..)) + | PredicateKind::Clause(ClauseKind::ConstEvaluatable(..)) | PredicateKind::ConstEquate(..) - | PredicateKind::Ambiguous - | PredicateKind::TypeWellFormedFromEnv(..) => None, + | PredicateKind::Ambiguous => None, } } pub fn to_opt_type_outlives(self) -> Option<PolyTypeOutlivesPredicate<'tcx>> { let predicate = self.kind(); match predicate.skip_binder() { - PredicateKind::Clause(Clause::TypeOutlives(data)) => Some(predicate.rebind(data)), - PredicateKind::Clause(Clause::Trait(..)) - | PredicateKind::Clause(Clause::ConstArgHasType(..)) - | PredicateKind::Clause(Clause::Projection(..)) + PredicateKind::Clause(ClauseKind::TypeOutlives(data)) => Some(predicate.rebind(data)), + PredicateKind::Clause(ClauseKind::Trait(..)) + | PredicateKind::Clause(ClauseKind::ConstArgHasType(..)) + | PredicateKind::Clause(ClauseKind::Projection(..)) | PredicateKind::AliasRelate(..) | PredicateKind::Subtype(..) | PredicateKind::Coerce(..) - | PredicateKind::Clause(Clause::RegionOutlives(..)) - | PredicateKind::WellFormed(..) + | PredicateKind::Clause(ClauseKind::RegionOutlives(..)) + | PredicateKind::Clause(ClauseKind::WellFormed(..)) | PredicateKind::ObjectSafe(..) | PredicateKind::ClosureKind(..) - | PredicateKind::ConstEvaluatable(..) + | PredicateKind::Clause(ClauseKind::ConstEvaluatable(..)) | PredicateKind::ConstEquate(..) - | PredicateKind::Ambiguous - | PredicateKind::TypeWellFormedFromEnv(..) => None, + | PredicateKind::Ambiguous => None, + } + } + + /// Matches a `PredicateKind::Clause` and turns it into a `Clause`, otherwise returns `None`. + pub fn as_clause(self) -> Option<Clause<'tcx>> { + match self.kind().skip_binder() { + PredicateKind::Clause(..) => Some(self.expect_clause()), + _ => None, + } + } + + /// Assert that the predicate is a clause. + pub fn expect_clause(self) -> Clause<'tcx> { + match self.kind().skip_binder() { + PredicateKind::Clause(..) => Clause(self.0), + _ => bug!("{self} is not a clause"), } } } @@ -1350,7 +1489,7 @@ impl<'tcx> Predicate<'tcx> { /// [usize:Bar<isize>]]`. #[derive(Clone, Debug, TypeFoldable, TypeVisitable)] pub struct InstantiatedPredicates<'tcx> { - pub predicates: Vec<Predicate<'tcx>>, + pub predicates: Vec<Clause<'tcx>>, pub spans: Vec<Span>, } @@ -1369,9 +1508,9 @@ impl<'tcx> InstantiatedPredicates<'tcx> { } impl<'tcx> IntoIterator for InstantiatedPredicates<'tcx> { - type Item = (Predicate<'tcx>, Span); + type Item = (Clause<'tcx>, Span); - type IntoIter = std::iter::Zip<std::vec::IntoIter<Predicate<'tcx>>, std::vec::IntoIter<Span>>; + type IntoIter = std::iter::Zip<std::vec::IntoIter<Clause<'tcx>>, std::vec::IntoIter<Span>>; fn into_iter(self) -> Self::IntoIter { debug_assert_eq!(self.predicates.len(), self.spans.len()); @@ -1380,10 +1519,10 @@ impl<'tcx> IntoIterator for InstantiatedPredicates<'tcx> { } impl<'a, 'tcx> IntoIterator for &'a InstantiatedPredicates<'tcx> { - type Item = (Predicate<'tcx>, Span); + type Item = (Clause<'tcx>, Span); type IntoIter = std::iter::Zip< - std::iter::Copied<std::slice::Iter<'a, Predicate<'tcx>>>, + std::iter::Copied<std::slice::Iter<'a, Clause<'tcx>>>, std::iter::Copied<std::slice::Iter<'a, Span>>, >; @@ -1397,7 +1536,7 @@ impl<'a, 'tcx> IntoIterator for &'a InstantiatedPredicates<'tcx> { #[derive(TypeFoldable, TypeVisitable)] pub struct OpaqueTypeKey<'tcx> { pub def_id: LocalDefId, - pub substs: SubstsRef<'tcx>, + pub args: GenericArgsRef<'tcx>, } #[derive(Copy, Clone, Debug, TypeFoldable, TypeVisitable, HashStable, TyEncodable, TyDecodable)] @@ -1468,21 +1607,21 @@ impl<'tcx> OpaqueHiddenType<'tcx> { // typeck errors have subpar spans for opaque types, so delay error reporting until borrowck. ignore_errors: bool, ) -> Self { - let OpaqueTypeKey { def_id, substs } = opaque_type_key; + let OpaqueTypeKey { def_id, args } = opaque_type_key; - // Use substs to build up a reverse map from regions to their + // Use args to build up a reverse map from regions to their // identity mappings. This is necessary because of `impl // Trait` lifetimes are computed by replacing existing // lifetimes with 'static and remapping only those used in the // `impl Trait` return type, resulting in the parameters // shifting. - let id_substs = InternalSubsts::identity_for_item(tcx, def_id); - debug!(?id_substs); + let id_args = GenericArgs::identity_for_item(tcx, def_id); + debug!(?id_args); - // This zip may have several times the same lifetime in `substs` paired with a different - // lifetime from `id_substs`. Simply `collect`ing the iterator is the correct behaviour: + // This zip may have several times the same lifetime in `args` paired with a different + // lifetime from `id_args`. Simply `collect`ing the iterator is the correct behaviour: // it will pick the last one, which is the one we introduced in the impl-trait desugaring. - let map = substs.iter().zip(id_substs).collect(); + let map = args.iter().zip(id_args).collect(); debug!("map = {:#?}", map); // Convert the type from the function into a type valid outside @@ -1533,21 +1672,18 @@ pub struct ParamEnv<'tcx> { /// want `Reveal::All`. /// /// Note: This is packed, use the reveal() method to access it. - packed: CopyTaggedPtr<&'tcx List<Predicate<'tcx>>, ParamTag, true>, + packed: CopyTaggedPtr<&'tcx List<Clause<'tcx>>, ParamTag, true>, } #[derive(Copy, Clone)] struct ParamTag { reveal: traits::Reveal, - constness: hir::Constness, } impl_tag! { impl Tag for ParamTag; - ParamTag { reveal: traits::Reveal::UserFacing, constness: hir::Constness::NotConst }, - ParamTag { reveal: traits::Reveal::All, constness: hir::Constness::NotConst }, - ParamTag { reveal: traits::Reveal::UserFacing, constness: hir::Constness::Const }, - ParamTag { reveal: traits::Reveal::All, constness: hir::Constness::Const }, + ParamTag { reveal: traits::Reveal::UserFacing }, + ParamTag { reveal: traits::Reveal::All }, } impl<'tcx> fmt::Debug for ParamEnv<'tcx> { @@ -1555,7 +1691,6 @@ impl<'tcx> fmt::Debug for ParamEnv<'tcx> { f.debug_struct("ParamEnv") .field("caller_bounds", &self.caller_bounds()) .field("reveal", &self.reveal()) - .field("constness", &self.constness()) .finish() } } @@ -1564,7 +1699,6 @@ impl<'a, 'tcx> HashStable<StableHashingContext<'a>> for ParamEnv<'tcx> { fn hash_stable(&self, hcx: &mut StableHashingContext<'a>, hasher: &mut StableHasher) { self.caller_bounds().hash_stable(hcx, hasher); self.reveal().hash_stable(hcx, hasher); - self.constness().hash_stable(hcx, hasher); } } @@ -1576,7 +1710,6 @@ impl<'tcx> TypeFoldable<TyCtxt<'tcx>> for ParamEnv<'tcx> { Ok(ParamEnv::new( self.caller_bounds().try_fold_with(folder)?, self.reveal().try_fold_with(folder)?, - self.constness(), )) } } @@ -1595,11 +1728,11 @@ impl<'tcx> ParamEnv<'tcx> { /// type-checking. #[inline] pub fn empty() -> Self { - Self::new(List::empty(), Reveal::UserFacing, hir::Constness::NotConst) + Self::new(List::empty(), Reveal::UserFacing) } #[inline] - pub fn caller_bounds(self) -> &'tcx List<Predicate<'tcx>> { + pub fn caller_bounds(self) -> &'tcx List<Clause<'tcx>> { self.packed.pointer() } @@ -1608,16 +1741,6 @@ impl<'tcx> ParamEnv<'tcx> { self.packed.tag().reveal } - #[inline] - pub fn constness(self) -> hir::Constness { - self.packed.tag().constness - } - - #[inline] - pub fn is_const(self) -> bool { - self.packed.tag().constness == hir::Constness::Const - } - /// Construct a trait environment with no where-clauses in scope /// where the values of all `impl Trait` and other hidden types /// are revealed. This is suitable for monomorphized, post-typeck @@ -1627,17 +1750,13 @@ impl<'tcx> ParamEnv<'tcx> { /// or invoke `param_env.with_reveal_all()`. #[inline] pub fn reveal_all() -> Self { - Self::new(List::empty(), Reveal::All, hir::Constness::NotConst) + Self::new(List::empty(), Reveal::All) } /// Construct a trait environment with the given set of predicates. #[inline] - pub fn new( - caller_bounds: &'tcx List<Predicate<'tcx>>, - reveal: Reveal, - constness: hir::Constness, - ) -> Self { - ty::ParamEnv { packed: CopyTaggedPtr::new(caller_bounds, ParamTag { reveal, constness }) } + pub fn new(caller_bounds: &'tcx List<Clause<'tcx>>, reveal: Reveal) -> Self { + ty::ParamEnv { packed: CopyTaggedPtr::new(caller_bounds, ParamTag { reveal }) } } pub fn with_user_facing(mut self) -> Self { @@ -1645,29 +1764,6 @@ impl<'tcx> ParamEnv<'tcx> { self } - #[inline] - pub fn with_constness(mut self, constness: hir::Constness) -> Self { - self.packed.set_tag(ParamTag { constness, ..self.packed.tag() }); - self - } - - #[inline] - pub fn with_const(mut self) -> Self { - self.packed.set_tag(ParamTag { constness: hir::Constness::Const, ..self.packed.tag() }); - self - } - - #[inline] - pub fn without_const(mut self) -> Self { - self.packed.set_tag(ParamTag { constness: hir::Constness::NotConst, ..self.packed.tag() }); - self - } - - #[inline] - pub fn remap_constness_with(&mut self, mut constness: ty::BoundConstness) { - *self = self.with_constness(constness.and(self.constness())) - } - /// Returns a new parameter environment with the same clauses, but /// which "reveals" the true results of projections in all cases /// (even for associated types that are specializable). This is @@ -1682,17 +1778,13 @@ impl<'tcx> ParamEnv<'tcx> { return self; } - ParamEnv::new( - tcx.reveal_opaque_types_in_bounds(self.caller_bounds()), - Reveal::All, - self.constness(), - ) + ParamEnv::new(tcx.reveal_opaque_types_in_bounds(self.caller_bounds()), Reveal::All) } /// Returns this same environment but with no caller bounds. #[inline] pub fn without_caller_bounds(self) -> Self { - Self::new(List::empty(), self.reveal(), self.constness()) + Self::new(List::empty(), self.reveal()) } /// Creates a suitable environment in which to perform trait @@ -1874,6 +1966,22 @@ impl VariantDef { &self.fields[FieldIdx::from_u32(0)] } + + /// Returns the last field in this variant, if present. + #[inline] + pub fn tail_opt(&self) -> Option<&FieldDef> { + self.fields.raw.last() + } + + /// Returns the last field in this variant. + /// + /// # Panics + /// + /// Panics, if the variant has no fields. + #[inline] + pub fn tail(&self) -> &FieldDef { + self.tail_opt().expect("expected unsized ADT to have a tail field") + } } impl PartialEq for VariantDef { @@ -1987,10 +2095,10 @@ impl Hash for FieldDef { } impl<'tcx> FieldDef { - /// Returns the type of this field. The resulting type is not normalized. The `subst` is + /// Returns the type of this field. The resulting type is not normalized. The `arg` is /// typically obtained via the second field of [`TyKind::Adt`]. - pub fn ty(&self, tcx: TyCtxt<'tcx>, subst: SubstsRef<'tcx>) -> Ty<'tcx> { - tcx.type_of(self.did).subst(tcx, subst) + pub fn ty(&self, tcx: TyCtxt<'tcx>, arg: GenericArgsRef<'tcx>) -> Ty<'tcx> { + tcx.type_of(self.did).instantiate(tcx, arg) } /// Computes the `Ident` of this variant by looking up the `Span` @@ -2214,8 +2322,8 @@ impl<'tcx> TyCtxt<'tcx> { let impl_trait_ref2 = self.impl_trait_ref(def_id2); // If either trait impl references an error, they're allowed to overlap, // as one of them essentially doesn't exist. - if impl_trait_ref1.is_some_and(|tr| tr.subst_identity().references_error()) - || impl_trait_ref2.is_some_and(|tr| tr.subst_identity().references_error()) + if impl_trait_ref1.is_some_and(|tr| tr.instantiate_identity().references_error()) + || impl_trait_ref2.is_some_and(|tr| tr.instantiate_identity().references_error()) { return Some(ImplOverlapKind::Permitted { marker: false }); } @@ -2511,7 +2619,6 @@ impl<'tcx> TyCtxt<'tcx> { | Some(ImplTraitInTraitData::Impl { fn_def_id, .. }) => fn_def_id, None => { while let def_kind = self.def_kind(def_id) && def_kind != DefKind::AssocFn { - debug_assert_eq!(def_kind, DefKind::ImplTraitPlaceholder); def_id = self.parent(def_id); } def_id @@ -2536,33 +2643,20 @@ impl<'tcx> TyCtxt<'tcx> { return false; } - let Some(item) = self.opt_associated_item(def_id) else { return false; }; + let Some(item) = self.opt_associated_item(def_id) else { + return false; + }; if item.container != ty::AssocItemContainer::ImplContainer { return false; } - let Some(trait_item_def_id) = item.trait_item_def_id else { return false; }; - - if self.lower_impl_trait_in_trait_to_assoc_ty() { - return !self - .associated_types_for_impl_traits_in_associated_fn(trait_item_def_id) - .is_empty(); - } + let Some(trait_item_def_id) = item.trait_item_def_id else { + return false; + }; - // FIXME(RPITIT): This does a somewhat manual walk through the signature - // of the trait fn to look for any RPITITs, but that's kinda doing a lot - // of work. We can probably remove this when we refactor RPITITs to be - // associated types. - self.fn_sig(trait_item_def_id).subst_identity().skip_binder().output().walk().any(|arg| { - if let ty::GenericArgKind::Type(ty) = arg.unpack() - && let ty::Alias(ty::Projection, data) = ty.kind() - && self.def_kind(data.def_id) == DefKind::ImplTraitPlaceholder - { - true - } else { - false - } - }) + return !self + .associated_types_for_impl_traits_in_associated_fn(trait_item_def_id) + .is_empty(); } } |