diff options
Diffstat (limited to 'src/librustc_middle/traits/mod.rs')
| -rw-r--r-- | src/librustc_middle/traits/mod.rs | 153 |
1 files changed, 73 insertions, 80 deletions
diff --git a/src/librustc_middle/traits/mod.rs b/src/librustc_middle/traits/mod.rs index 9afab5a4d2f..56787304d4e 100644 --- a/src/librustc_middle/traits/mod.rs +++ b/src/librustc_middle/traits/mod.rs @@ -27,9 +27,9 @@ pub use self::select::{EvaluationCache, EvaluationResult, OverflowError, Selecti pub type ChalkCanonicalGoal<'tcx> = Canonical<'tcx, ChalkEnvironmentAndGoal<'tcx>>; +pub use self::ImplSource::*; pub use self::ObligationCauseCode::*; pub use self::SelectionError::*; -pub use self::Vtable::*; pub use self::chalk::{ ChalkEnvironmentAndGoal, ChalkEnvironmentClause, RustDefId as ChalkRustDefId, @@ -343,15 +343,10 @@ pub enum SelectionError<'tcx> { /// - `Err(e)`: error `e` occurred pub type SelectionResult<'tcx, T> = Result<Option<T>, SelectionError<'tcx>>; -/// Given the successful resolution of an obligation, the `Vtable` -/// indicates where the vtable comes from. Note that while we call this -/// a "vtable", it does not necessarily indicate dynamic dispatch at -/// runtime. `Vtable` instances just tell the compiler where to find -/// methods, but in generic code those methods are typically statically -/// dispatched -- only when an object is constructed is a `Vtable` -/// instance reified into an actual vtable. +/// Given the successful resolution of an obligation, the `ImplSource` +/// indicates where the impl comes from. /// -/// For example, the vtable may be tied to a specific impl (case A), +/// For example, the obligation may be satisfied by a specific impl (case A), /// or it may be relative to some bound that is in scope (case B). /// /// ``` @@ -363,136 +358,136 @@ pub type SelectionResult<'tcx, T> = Result<Option<T>, SelectionError<'tcx>>; /// param: T, /// mixed: Option<T>) { /// -/// // Case A: Vtable points at a specific impl. Only possible when +/// // Case A: ImplSource points at a specific impl. Only possible when /// // type is concretely known. If the impl itself has bounded -/// // type parameters, Vtable will carry resolutions for those as well: -/// concrete.clone(); // Vtable(Impl_1, [Vtable(Impl_2, [Vtable(Impl_3)])]) +/// // type parameters, ImplSource will carry resolutions for those as well: +/// concrete.clone(); // ImplSource(Impl_1, [ImplSource(Impl_2, [ImplSource(Impl_3)])]) /// -/// // Case B: Vtable must be provided by caller. This applies when +/// // Case B: ImplSource must be provided by caller. This applies when /// // type is a type parameter. -/// param.clone(); // VtableParam +/// param.clone(); // ImplSourceParam /// /// // Case C: A mix of cases A and B. -/// mixed.clone(); // Vtable(Impl_1, [VtableParam]) +/// mixed.clone(); // ImplSource(Impl_1, [ImplSourceParam]) /// } /// ``` /// /// ### The type parameter `N` /// -/// See explanation on `VtableImplData`. +/// See explanation on `ImplSourceUserDefinedData`. #[derive(Clone, PartialEq, Eq, RustcEncodable, RustcDecodable, HashStable, TypeFoldable)] -pub enum Vtable<'tcx, N> { - /// Vtable identifying a particular impl. - VtableImpl(VtableImplData<'tcx, N>), +pub enum ImplSource<'tcx, N> { + /// ImplSource identifying a particular impl. + ImplSourceUserDefined(ImplSourceUserDefinedData<'tcx, N>), - /// Vtable for auto trait implementations. + /// ImplSource for auto trait implementations. /// This carries the information and nested obligations with regards /// to an auto implementation for a trait `Trait`. The nested obligations /// ensure the trait implementation holds for all the constituent types. - VtableAutoImpl(VtableAutoImplData<N>), + ImplSourceAutoImpl(ImplSourceAutoImplData<N>), /// Successful resolution to an obligation provided by the caller /// for some type parameter. The `Vec<N>` represents the /// obligations incurred from normalizing the where-clause (if /// any). - VtableParam(Vec<N>), + ImplSourceParam(Vec<N>), /// Virtual calls through an object. - VtableObject(VtableObjectData<'tcx, N>), + ImplSourceObject(ImplSourceObjectData<'tcx, N>), /// Successful resolution for a builtin trait. - VtableBuiltin(VtableBuiltinData<N>), + ImplSourceBuiltin(ImplSourceBuiltinData<N>), - /// Vtable automatically generated for a closure. The `DefId` is the ID - /// of the closure expression. This is a `VtableImpl` in spirit, but the + /// ImplSource automatically generated for a closure. The `DefId` is the ID + /// of the closure expression. This is a `ImplSourceUserDefined` in spirit, but the /// impl is generated by the compiler and does not appear in the source. - VtableClosure(VtableClosureData<'tcx, N>), + ImplSourceClosure(ImplSourceClosureData<'tcx, N>), /// Same as above, but for a function pointer type with the given signature. - VtableFnPointer(VtableFnPointerData<'tcx, N>), + ImplSourceFnPointer(ImplSourceFnPointerData<'tcx, N>), - /// Vtable for a builtin `DeterminantKind` trait implementation. - VtableDiscriminantKind(VtableDiscriminantKindData), + /// ImplSource for a builtin `DeterminantKind` trait implementation. + ImplSourceDiscriminantKind(ImplSourceDiscriminantKindData), - /// Vtable automatically generated for a generator. - VtableGenerator(VtableGeneratorData<'tcx, N>), + /// ImplSource automatically generated for a generator. + ImplSourceGenerator(ImplSourceGeneratorData<'tcx, N>), - /// Vtable for a trait alias. - VtableTraitAlias(VtableTraitAliasData<'tcx, N>), + /// ImplSource for a trait alias. + ImplSourceTraitAlias(ImplSourceTraitAliasData<'tcx, N>), } -impl<'tcx, N> Vtable<'tcx, N> { +impl<'tcx, N> ImplSource<'tcx, N> { pub fn nested_obligations(self) -> Vec<N> { match self { - VtableImpl(i) => i.nested, - VtableParam(n) => n, - VtableBuiltin(i) => i.nested, - VtableAutoImpl(d) => d.nested, - VtableClosure(c) => c.nested, - VtableGenerator(c) => c.nested, - VtableObject(d) => d.nested, - VtableFnPointer(d) => d.nested, - VtableDiscriminantKind(VtableDiscriminantKindData) => Vec::new(), - VtableTraitAlias(d) => d.nested, + ImplSourceUserDefined(i) => i.nested, + ImplSourceParam(n) => n, + ImplSourceBuiltin(i) => i.nested, + ImplSourceAutoImpl(d) => d.nested, + ImplSourceClosure(c) => c.nested, + ImplSourceGenerator(c) => c.nested, + ImplSourceObject(d) => d.nested, + ImplSourceFnPointer(d) => d.nested, + ImplSourceDiscriminantKind(ImplSourceDiscriminantKindData) => Vec::new(), + ImplSourceTraitAlias(d) => d.nested, } } pub fn borrow_nested_obligations(&self) -> &[N] { match &self { - VtableImpl(i) => &i.nested[..], - VtableParam(n) => &n[..], - VtableBuiltin(i) => &i.nested[..], - VtableAutoImpl(d) => &d.nested[..], - VtableClosure(c) => &c.nested[..], - VtableGenerator(c) => &c.nested[..], - VtableObject(d) => &d.nested[..], - VtableFnPointer(d) => &d.nested[..], - VtableDiscriminantKind(VtableDiscriminantKindData) => &[], - VtableTraitAlias(d) => &d.nested[..], + ImplSourceUserDefined(i) => &i.nested[..], + ImplSourceParam(n) => &n[..], + ImplSourceBuiltin(i) => &i.nested[..], + ImplSourceAutoImpl(d) => &d.nested[..], + ImplSourceClosure(c) => &c.nested[..], + ImplSourceGenerator(c) => &c.nested[..], + ImplSourceObject(d) => &d.nested[..], + ImplSourceFnPointer(d) => &d.nested[..], + ImplSourceDiscriminantKind(ImplSourceDiscriminantKindData) => &[], + ImplSourceTraitAlias(d) => &d.nested[..], } } - pub fn map<M, F>(self, f: F) -> Vtable<'tcx, M> + pub fn map<M, F>(self, f: F) -> ImplSource<'tcx, M> where F: FnMut(N) -> M, { match self { - VtableImpl(i) => VtableImpl(VtableImplData { + ImplSourceUserDefined(i) => ImplSourceUserDefined(ImplSourceUserDefinedData { impl_def_id: i.impl_def_id, substs: i.substs, nested: i.nested.into_iter().map(f).collect(), }), - VtableParam(n) => VtableParam(n.into_iter().map(f).collect()), - VtableBuiltin(i) => { - VtableBuiltin(VtableBuiltinData { nested: i.nested.into_iter().map(f).collect() }) - } - VtableObject(o) => VtableObject(VtableObjectData { + ImplSourceParam(n) => ImplSourceParam(n.into_iter().map(f).collect()), + ImplSourceBuiltin(i) => ImplSourceBuiltin(ImplSourceBuiltinData { + nested: i.nested.into_iter().map(f).collect(), + }), + ImplSourceObject(o) => ImplSourceObject(ImplSourceObjectData { upcast_trait_ref: o.upcast_trait_ref, vtable_base: o.vtable_base, nested: o.nested.into_iter().map(f).collect(), }), - VtableAutoImpl(d) => VtableAutoImpl(VtableAutoImplData { + ImplSourceAutoImpl(d) => ImplSourceAutoImpl(ImplSourceAutoImplData { trait_def_id: d.trait_def_id, nested: d.nested.into_iter().map(f).collect(), }), - VtableClosure(c) => VtableClosure(VtableClosureData { + ImplSourceClosure(c) => ImplSourceClosure(ImplSourceClosureData { closure_def_id: c.closure_def_id, substs: c.substs, nested: c.nested.into_iter().map(f).collect(), }), - VtableGenerator(c) => VtableGenerator(VtableGeneratorData { + ImplSourceGenerator(c) => ImplSourceGenerator(ImplSourceGeneratorData { generator_def_id: c.generator_def_id, substs: c.substs, nested: c.nested.into_iter().map(f).collect(), }), - VtableFnPointer(p) => VtableFnPointer(VtableFnPointerData { + ImplSourceFnPointer(p) => ImplSourceFnPointer(ImplSourceFnPointerData { fn_ty: p.fn_ty, nested: p.nested.into_iter().map(f).collect(), }), - VtableDiscriminantKind(VtableDiscriminantKindData) => { - VtableDiscriminantKind(VtableDiscriminantKindData) + ImplSourceDiscriminantKind(ImplSourceDiscriminantKindData) => { + ImplSourceDiscriminantKind(ImplSourceDiscriminantKindData) } - VtableTraitAlias(d) => VtableTraitAlias(VtableTraitAliasData { + ImplSourceTraitAlias(d) => ImplSourceTraitAlias(ImplSourceTraitAliasData { alias_def_id: d.alias_def_id, substs: d.substs, nested: d.nested.into_iter().map(f).collect(), @@ -512,14 +507,14 @@ impl<'tcx, N> Vtable<'tcx, N> { /// is `()`, because codegen only requires a shallow resolution of an /// impl, and nested obligations are satisfied later. #[derive(Clone, PartialEq, Eq, RustcEncodable, RustcDecodable, HashStable, TypeFoldable)] -pub struct VtableImplData<'tcx, N> { +pub struct ImplSourceUserDefinedData<'tcx, N> { pub impl_def_id: DefId, pub substs: SubstsRef<'tcx>, pub nested: Vec<N>, } #[derive(Clone, PartialEq, Eq, RustcEncodable, RustcDecodable, HashStable, TypeFoldable)] -pub struct VtableGeneratorData<'tcx, N> { +pub struct ImplSourceGeneratorData<'tcx, N> { pub generator_def_id: DefId, pub substs: SubstsRef<'tcx>, /// Nested obligations. This can be non-empty if the generator @@ -528,7 +523,7 @@ pub struct VtableGeneratorData<'tcx, N> { } #[derive(Clone, PartialEq, Eq, RustcEncodable, RustcDecodable, HashStable, TypeFoldable)] -pub struct VtableClosureData<'tcx, N> { +pub struct ImplSourceClosureData<'tcx, N> { pub closure_def_id: DefId, pub substs: SubstsRef<'tcx>, /// Nested obligations. This can be non-empty if the closure @@ -537,20 +532,18 @@ pub struct VtableClosureData<'tcx, N> { } #[derive(Clone, PartialEq, Eq, RustcEncodable, RustcDecodable, HashStable, TypeFoldable)] -pub struct VtableAutoImplData<N> { +pub struct ImplSourceAutoImplData<N> { pub trait_def_id: DefId, pub nested: Vec<N>, } #[derive(Clone, PartialEq, Eq, RustcEncodable, RustcDecodable, HashStable, TypeFoldable)] -pub struct VtableBuiltinData<N> { +pub struct ImplSourceBuiltinData<N> { pub nested: Vec<N>, } -/// A vtable for some object-safe trait `Foo` automatically derived -/// for the object type `Foo`. #[derive(PartialEq, Eq, Clone, RustcEncodable, RustcDecodable, HashStable, TypeFoldable)] -pub struct VtableObjectData<'tcx, N> { +pub struct ImplSourceObjectData<'tcx, N> { /// `Foo` upcast to the obligation trait. This will be some supertrait of `Foo`. pub upcast_trait_ref: ty::PolyTraitRef<'tcx>, @@ -563,17 +556,17 @@ pub struct VtableObjectData<'tcx, N> { } #[derive(Clone, PartialEq, Eq, RustcEncodable, RustcDecodable, HashStable, TypeFoldable)] -pub struct VtableFnPointerData<'tcx, N> { +pub struct ImplSourceFnPointerData<'tcx, N> { pub fn_ty: Ty<'tcx>, pub nested: Vec<N>, } // FIXME(@lcnr): This should be refactored and merged with other builtin vtables. #[derive(Clone, Debug, PartialEq, Eq, RustcEncodable, RustcDecodable, HashStable, TypeFoldable)] -pub struct VtableDiscriminantKindData; +pub struct ImplSourceDiscriminantKindData; #[derive(Clone, PartialEq, Eq, RustcEncodable, RustcDecodable, HashStable, TypeFoldable)] -pub struct VtableTraitAliasData<'tcx, N> { +pub struct ImplSourceTraitAliasData<'tcx, N> { pub alias_def_id: DefId, pub substs: SubstsRef<'tcx>, pub nested: Vec<N>, |