Uplift `NormalizesTo`, `CoercePredicate`, and `SubtypePredicate`

10 files changed, 128 insertions, 87 deletions

diff --git a/compiler/rustc_errors/src/diagnostic_impls.rs b/compiler/rustc_errors/src/diagnostic_impls.rs
index 60a2f5469fe..2cc0167dbaa 100644
--- a/compiler/rustc_errors/src/diagnostic_impls.rs
+++ b/compiler/rustc_errors/src/diagnostic_impls.rs
@@ -100,8 +100,6 @@ impl<I: rustc_type_ir::Interner> IntoDiagArg for rustc_type_ir::TraitRef<I> {
     }
 }
 
-
-
 impl<I: rustc_type_ir::Interner> IntoDiagArg for rustc_type_ir::ExistentialTraitRef<I> {
     fn into_diag_arg(self) -> DiagArgValue {
         self.to_string().into_diag_arg()
diff --git a/compiler/rustc_middle/src/ty/context.rs b/compiler/rustc_middle/src/ty/context.rs
index 93fba3fbc86..70fb937cae7 100644
--- a/compiler/rustc_middle/src/ty/context.rs
+++ b/compiler/rustc_middle/src/ty/context.rs
@@ -149,7 +149,7 @@ impl<'tcx> Interner for TyCtxt<'tcx> {
     fn mk_args(self, args: &[Self::GenericArg]) -> Self::GenericArgs {
         self.mk_args(args)
     }
-    
+
     fn check_and_mk_args(
         self,
         def_id: DefId,
@@ -157,7 +157,7 @@ impl<'tcx> Interner for TyCtxt<'tcx> {
     ) -> ty::GenericArgsRef<'tcx> {
         self.check_and_mk_args(def_id, args)
     }
-    
+
     fn parent(self, def_id: Self::DefId) -> Self::DefId {
         self.parent(def_id)
     }
diff --git a/compiler/rustc_middle/src/ty/predicate.rs b/compiler/rustc_middle/src/ty/predicate.rs
index bc5f75f58c3..dbbb86cb28e 100644
--- a/compiler/rustc_middle/src/ty/predicate.rs
+++ b/compiler/rustc_middle/src/ty/predicate.rs
@@ -3,17 +3,20 @@ use rustc_data_structures::intern::Interned;
 use rustc_hir::def_id::DefId;
 use rustc_macros::{HashStable, Lift, TyDecodable, TyEncodable, TypeFoldable, TypeVisitable};
 use rustc_type_ir::ClauseKind as IrClauseKind;
+use rustc_type_ir::CoercePredicate as IrCoercePredicate;
+use rustc_type_ir::ExistentialProjection as IrExistentialProjection;
+use rustc_type_ir::ExistentialTraitRef as IrExistentialTraitRef;
+use rustc_type_ir::NormalizesTo as IrNormalizesTo;
 use rustc_type_ir::PredicateKind as IrPredicateKind;
+use rustc_type_ir::ProjectionPredicate as IrProjectionPredicate;
+use rustc_type_ir::SubtypePredicate as IrSubtypePredicate;
 use rustc_type_ir::TraitPredicate as IrTraitPredicate;
 use rustc_type_ir::TraitRef as IrTraitRef;
-use rustc_type_ir::ProjectionPredicate as IrProjectionPredicate;
-use rustc_type_ir::ExistentialTraitRef as IrExistentialTraitRef;
-use rustc_type_ir::ExistentialProjection as IrExistentialProjection;
 use std::cmp::Ordering;
 
 use crate::ty::{
-    self, AliasTy, Binder, DebruijnIndex, DebugWithInfcx, EarlyBinder,
-    PredicatePolarity, Term, Ty, TyCtxt, TypeFlags, WithCachedTypeInfo,
+    self, Binder, DebruijnIndex, DebugWithInfcx, EarlyBinder, PredicatePolarity, Term, Ty, TyCtxt,
+    TypeFlags, WithCachedTypeInfo,
 };
 
 pub type TraitRef<'tcx> = IrTraitRef<TyCtxt<'tcx>>;
@@ -23,6 +26,9 @@ pub type ExistentialProjection<'tcx> = IrExistentialProjection<TyCtxt<'tcx>>;
 pub type TraitPredicate<'tcx> = IrTraitPredicate<TyCtxt<'tcx>>;
 pub type ClauseKind<'tcx> = IrClauseKind<TyCtxt<'tcx>>;
 pub type PredicateKind<'tcx> = IrPredicateKind<TyCtxt<'tcx>>;
+pub type NormalizesTo<'tcx> = IrNormalizesTo<TyCtxt<'tcx>>;
+pub type CoercePredicate<'tcx> = IrCoercePredicate<TyCtxt<'tcx>>;
+pub type SubtypePredicate<'tcx> = IrSubtypePredicate<TyCtxt<'tcx>>;
 
 /// 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,
@@ -511,25 +517,8 @@ pub type TypeOutlivesPredicate<'tcx> = OutlivesPredicate<Ty<'tcx>, ty::Region<'t
 pub type PolyRegionOutlivesPredicate<'tcx> = ty::Binder<'tcx, RegionOutlivesPredicate<'tcx>>;
 pub type PolyTypeOutlivesPredicate<'tcx> = ty::Binder<'tcx, TypeOutlivesPredicate<'tcx>>;
 
-/// Encodes that `a` must be a subtype of `b`. The `a_is_expected` flag indicates
-/// whether the `a` type is the type that we should label as "expected" when
-/// presenting user diagnostics.
-#[derive(Clone, Copy, PartialEq, Eq, Hash, Debug, TyEncodable, TyDecodable)]
-#[derive(HashStable, TypeFoldable, TypeVisitable, Lift)]
-pub struct SubtypePredicate<'tcx> {
-    pub a_is_expected: bool,
-    pub a: Ty<'tcx>,
-    pub b: Ty<'tcx>,
-}
 pub type PolySubtypePredicate<'tcx> = ty::Binder<'tcx, SubtypePredicate<'tcx>>;
 
-/// Encodes that we have to coerce *from* the `a` type to the `b` type.
-#[derive(Clone, Copy, PartialEq, Eq, Hash, Debug, TyEncodable, TyDecodable)]
-#[derive(HashStable, TypeFoldable, TypeVisitable, Lift)]
-pub struct CoercePredicate<'tcx> {
-    pub a: Ty<'tcx>,
-    pub b: Ty<'tcx>,
-}
 pub type PolyCoercePredicate<'tcx> = ty::Binder<'tcx, CoercePredicate<'tcx>>;
 
 pub type PolyProjectionPredicate<'tcx> = Binder<'tcx, ProjectionPredicate<'tcx>>;
@@ -568,33 +557,6 @@ impl<'tcx> PolyProjectionPredicate<'tcx> {
     }
 }
 
-/// Used by the new solver. Unlike a `ProjectionPredicate` this can only be
-/// proven by actually normalizing `alias`.
-#[derive(Copy, Clone, PartialEq, Eq, Hash, TyEncodable, TyDecodable)]
-#[derive(HashStable, TypeFoldable, TypeVisitable, Lift)]
-pub struct NormalizesTo<'tcx> {
-    pub alias: AliasTy<'tcx>,
-    pub term: Term<'tcx>,
-}
-
-impl<'tcx> NormalizesTo<'tcx> {
-    pub fn self_ty(self) -> Ty<'tcx> {
-        self.alias.self_ty()
-    }
-
-    pub fn with_self_ty(self, tcx: TyCtxt<'tcx>, self_ty: Ty<'tcx>) -> NormalizesTo<'tcx> {
-        Self { alias: self.alias.with_self_ty(tcx, self_ty), ..self }
-    }
-
-    pub fn trait_def_id(self, tcx: TyCtxt<'tcx>) -> DefId {
-        self.alias.trait_def_id(tcx)
-    }
-
-    pub fn def_id(self) -> DefId {
-        self.alias.def_id
-    }
-}
-
 pub trait ToPolyTraitRef<'tcx> {
     fn to_poly_trait_ref(&self) -> PolyTraitRef<'tcx>;
 }
diff --git a/compiler/rustc_middle/src/ty/print/pretty.rs b/compiler/rustc_middle/src/ty/print/pretty.rs
index 9e5edb97fe2..6137a5fd48a 100644
--- a/compiler/rustc_middle/src/ty/print/pretty.rs
+++ b/compiler/rustc_middle/src/ty/print/pretty.rs
@@ -3105,6 +3105,24 @@ define_print! {
         cx.reset_type_limit();
         p!(print(self.term))
     }
+
+    ty::SubtypePredicate<'tcx> {
+        p!(print(self.a), " <: ");
+        cx.reset_type_limit();
+        p!(print(self.b))
+    }
+
+    ty::CoercePredicate<'tcx> {
+        p!(print(self.a), " -> ");
+        cx.reset_type_limit();
+        p!(print(self.b))
+    }
+
+    ty::NormalizesTo<'tcx> {
+        p!(print(self.alias), " normalizes-to ");
+        cx.reset_type_limit();
+        p!(print(self.term))
+    }
 }
 
 define_print_and_forward_display! {
@@ -3180,24 +3198,6 @@ define_print_and_forward_display! {
         p!(write("{}", self.name))
     }
 
-    ty::SubtypePredicate<'tcx> {
-        p!(print(self.a), " <: ");
-        cx.reset_type_limit();
-        p!(print(self.b))
-    }
-
-    ty::CoercePredicate<'tcx> {
-        p!(print(self.a), " -> ");
-        cx.reset_type_limit();
-        p!(print(self.b))
-    }
-
-    ty::NormalizesTo<'tcx> {
-        p!(print(self.alias), " normalizes-to ");
-        cx.reset_type_limit();
-        p!(print(self.term))
-    }
-
     ty::Term<'tcx> {
       match self.unpack() {
         ty::TermKind::Ty(ty) => p!(print(ty)),
diff --git a/compiler/rustc_middle/src/ty/structural_impls.rs b/compiler/rustc_middle/src/ty/structural_impls.rs
index b08ae4e5890..dc071b295aa 100644
--- a/compiler/rustc_middle/src/ty/structural_impls.rs
+++ b/compiler/rustc_middle/src/ty/structural_impls.rs
@@ -152,12 +152,6 @@ impl fmt::Debug for ty::ParamConst {
     }
 }
 
-impl<'tcx> fmt::Debug for ty::NormalizesTo<'tcx> {
-    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        write!(f, "NormalizesTo({:?}, {:?})", self.alias, self.term)
-    }
-}
-
 impl<'tcx> fmt::Debug for ty::Predicate<'tcx> {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         write!(f, "{:?}", self.kind())
diff --git a/compiler/rustc_type_ir/src/inherent.rs b/compiler/rustc_type_ir/src/inherent.rs
index cf67f82efd7..a50967a3b18 100644
--- a/compiler/rustc_type_ir/src/inherent.rs
+++ b/compiler/rustc_type_ir/src/inherent.rs
@@ -90,7 +90,7 @@ pub trait BoundVars<I: Interner> {
     fn has_no_bound_vars(&self) -> bool;
 }
 
-// TODO: Uplift `AliasTy`
+// FIXME: Uplift `AliasTy`
 pub trait AliasTy<I: Interner>: Copy + DebugWithInfcx<I> + Hash + Eq + Sized {
     fn new(
         interner: I,
@@ -107,5 +107,4 @@ pub trait AliasTy<I: Interner>: Copy + DebugWithInfcx<I> + Hash + Eq + Sized {
     fn self_ty(self) -> I::Ty;
 
     fn with_self_ty(self, tcx: I, self_ty: I::Ty) -> Self;
-
 }
diff --git a/compiler/rustc_type_ir/src/interner.rs b/compiler/rustc_type_ir/src/interner.rs
index bfa769237a1..17d9f4242fd 100644
--- a/compiler/rustc_type_ir/src/interner.rs
+++ b/compiler/rustc_type_ir/src/interner.rs
@@ -6,8 +6,8 @@ use crate::inherent::*;
 use crate::ir_print::IrPrint;
 use crate::visit::{Flags, TypeSuperVisitable, TypeVisitable};
 use crate::{
-    CanonicalVarInfo, DebugWithInfcx, ExistentialProjection, ExistentialTraitRef,
-    ProjectionPredicate, TraitPredicate, TraitRef,
+    CanonicalVarInfo, CoercePredicate, DebugWithInfcx, ExistentialProjection, ExistentialTraitRef,
+    NormalizesTo, ProjectionPredicate, SubtypePredicate, TraitPredicate, TraitRef,
 };
 
 pub trait Interner:
@@ -18,6 +18,9 @@ pub trait Interner:
     + IrPrint<ExistentialTraitRef<Self>>
     + IrPrint<ExistentialProjection<Self>>
     + IrPrint<ProjectionPredicate<Self>>
+    + IrPrint<NormalizesTo<Self>>
+    + IrPrint<SubtypePredicate<Self>>
+    + IrPrint<CoercePredicate<Self>>
 {
     type DefId: Copy + Debug + Hash + Eq;
     type DefiningOpaqueTypes: Copy + Debug + Hash + Default + Eq + TypeVisitable<Self>;
diff --git a/compiler/rustc_type_ir/src/ir_print.rs b/compiler/rustc_type_ir/src/ir_print.rs
index 9b72764b4d1..5885139754a 100644
--- a/compiler/rustc_type_ir/src/ir_print.rs
+++ b/compiler/rustc_type_ir/src/ir_print.rs
@@ -1,8 +1,8 @@
 use std::fmt;
 
 use crate::{
-    ExistentialProjection, ExistentialTraitRef, Interner, ProjectionPredicate, TraitPredicate,
-    TraitRef,
+    CoercePredicate, ExistentialProjection, ExistentialTraitRef, Interner, NormalizesTo,
+    ProjectionPredicate, SubtypePredicate, TraitPredicate, TraitRef,
 };
 
 pub trait IrPrint<T> {
@@ -39,7 +39,10 @@ define_display_via_print!(
     TraitPredicate,
     ExistentialTraitRef,
     ExistentialProjection,
-    ProjectionPredicate
+    ProjectionPredicate,
+    NormalizesTo,
+    SubtypePredicate,
+    CoercePredicate,
 );
 
 define_debug_via_print!(TraitRef, ExistentialTraitRef, ExistentialProjection);
diff --git a/compiler/rustc_type_ir/src/lib.rs b/compiler/rustc_type_ir/src/lib.rs
index 184b882c2b7..04cacd987d0 100644
--- a/compiler/rustc_type_ir/src/lib.rs
+++ b/compiler/rustc_type_ir/src/lib.rs
@@ -37,9 +37,9 @@ mod debug;
 mod flags;
 mod infcx;
 mod interner;
+mod predicate;
 mod predicate_kind;
 mod region_kind;
-mod predicate;
 
 pub use canonical::*;
 #[cfg(feature = "nightly")]
@@ -49,9 +49,9 @@ pub use debug::{DebugWithInfcx, WithInfcx};
 pub use flags::*;
 pub use infcx::InferCtxtLike;
 pub use interner::*;
+pub use predicate::*;
 pub use predicate_kind::*;
 pub use region_kind::*;
-pub use predicate::*;
 pub use ty_info::*;
 pub use ty_kind::*;
 pub use AliasKind::*;
diff --git a/compiler/rustc_type_ir/src/predicate.rs b/compiler/rustc_type_ir/src/predicate.rs
index 9cd9319a1b1..b16227ee10f 100644
--- a/compiler/rustc_type_ir/src/predicate.rs
+++ b/compiler/rustc_type_ir/src/predicate.rs
@@ -187,7 +187,11 @@ impl<I: Interner> ExistentialTraitRef<I> {
         // otherwise the escaping vars would be captured by the binder
         // debug_assert!(!self_ty.has_escaping_bound_vars());
 
-        TraitRef::new(interner, self.def_id, [self_ty.into()].into_iter().chain(self.args.into_iter()))
+        TraitRef::new(
+            interner,
+            self.def_id,
+            [self_ty.into()].into_iter().chain(self.args.into_iter()),
+        )
     }
 }
 
@@ -296,3 +300,81 @@ impl<I: Interner> fmt::Debug for ProjectionPredicate<I> {
         write!(f, "ProjectionPredicate({:?}, {:?})", self.projection_ty, self.term)
     }
 }
+
+/// Used by the new solver. Unlike a `ProjectionPredicate` this can only be
+/// proven by actually normalizing `alias`.
+#[derive(derivative::Derivative)]
+#[derivative(
+    Clone(bound = ""),
+    Copy(bound = ""),
+    Hash(bound = ""),
+    PartialEq(bound = ""),
+    Eq(bound = "")
+)]
+#[derive(TypeVisitable_Generic, TypeFoldable_Generic, Lift_Generic)]
+#[cfg_attr(feature = "nightly", derive(TyDecodable, TyEncodable, HashStable_NoContext))]
+pub struct NormalizesTo<I: Interner> {
+    pub alias: I::AliasTy,
+    pub term: I::Term,
+}
+
+impl<I: Interner> NormalizesTo<I> {
+    pub fn self_ty(self) -> I::Ty {
+        self.alias.self_ty()
+    }
+
+    pub fn with_self_ty(self, tcx: I, self_ty: I::Ty) -> NormalizesTo<I> {
+        Self { alias: self.alias.with_self_ty(tcx, self_ty), ..self }
+    }
+
+    pub fn trait_def_id(self, tcx: I) -> I::DefId {
+        self.alias.trait_def_id(tcx)
+    }
+
+    pub fn def_id(self) -> I::DefId {
+        self.alias.def_id()
+    }
+}
+
+impl<I: Interner> fmt::Debug for NormalizesTo<I> {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        write!(f, "NormalizesTo({:?}, {:?})", self.alias, self.term)
+    }
+}
+
+/// Encodes that `a` must be a subtype of `b`. The `a_is_expected` flag indicates
+/// whether the `a` type is the type that we should label as "expected" when
+/// presenting user diagnostics.
+#[derive(derivative::Derivative)]
+#[derivative(
+    Clone(bound = ""),
+    Copy(bound = ""),
+    Hash(bound = ""),
+    PartialEq(bound = ""),
+    Eq(bound = ""),
+    Debug(bound = "")
+)]
+#[derive(TypeVisitable_Generic, TypeFoldable_Generic, Lift_Generic)]
+#[cfg_attr(feature = "nightly", derive(TyDecodable, TyEncodable, HashStable_NoContext))]
+pub struct SubtypePredicate<I: Interner> {
+    pub a_is_expected: bool,
+    pub a: I::Ty,
+    pub b: I::Ty,
+}
+
+/// Encodes that we have to coerce *from* the `a` type to the `b` type.
+#[derive(derivative::Derivative)]
+#[derivative(
+    Clone(bound = ""),
+    Copy(bound = ""),
+    Hash(bound = ""),
+    PartialEq(bound = ""),
+    Eq(bound = ""),
+    Debug(bound = "")
+)]
+#[derive(TypeVisitable_Generic, TypeFoldable_Generic, Lift_Generic)]
+#[cfg_attr(feature = "nightly", derive(TyDecodable, TyEncodable, HashStable_NoContext))]
+pub struct CoercePredicate<I: Interner> {
+    pub a: I::Ty,
+    pub b: I::Ty,
+}