2 files changed, 40 insertions, 84 deletions
diff --git a/compiler/rustc_middle/src/infer/canonical.rs b/compiler/rustc_middle/src/infer/canonical.rs
index 41beca072..64b63f4c5 100644
--- a/compiler/rustc_middle/src/infer/canonical.rs
+++ b/compiler/rustc_middle/src/infer/canonical.rs
@@ -21,35 +21,17 @@
 //!
 //! [c]: https://rust-lang.github.io/chalk/book/canonical_queries/canonicalization.html
 
-use crate::infer::MemberConstraint;
-use crate::mir::ConstraintCategory;
-use crate::ty::GenericArg;
-use crate::ty::{self, BoundVar, List, Region, Ty, TyCtxt};
 use rustc_macros::HashStable;
+use rustc_type_ir::Canonical as IrCanonical;
 use smallvec::SmallVec;
-use std::fmt::Display;
 use std::ops::Index;
 
-/// A "canonicalized" type `V` is one where all free inference
-/// variables have been rewritten to "canonical vars". These are
-/// numbered starting from 0 in order of first appearance.
-#[derive(Copy, Clone, Debug, PartialEq, Eq, Hash, TyDecodable, TyEncodable)]
-#[derive(HashStable, TypeFoldable, TypeVisitable)]
-pub struct Canonical<'tcx, V> {
-    pub value: V,
-    pub max_universe: ty::UniverseIndex,
-    pub variables: CanonicalVarInfos<'tcx>,
-}
+use crate::infer::MemberConstraint;
+use crate::mir::ConstraintCategory;
+use crate::ty::GenericArg;
+use crate::ty::{self, BoundVar, List, Region, Ty, TyCtxt};
 
-impl<'tcx, V: Display> std::fmt::Display for Canonical<'tcx, V> {
-    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
-        write!(
-            f,
-            "Canonical {{ value: {}, max_universe: {:?}, variables: {:?} }}",
-            self.value, self.max_universe, self.variables
-        )
-    }
-}
+pub type Canonical<'tcx, V> = IrCanonical<TyCtxt<'tcx>, V>;
 
 pub type CanonicalVarInfos<'tcx> = &'tcx List<CanonicalVarInfo<'tcx>>;
 
@@ -104,7 +86,7 @@ impl CanonicalVarValues<'_> {
                     } else {
                         // It's ok if this region var isn't unique
                     }
-                },
+                }
                 ty::GenericArgKind::Type(ty) => {
                     if let ty::Bound(ty::INNERMOST, bt) = *ty.kind()
                         && var == bt.var
@@ -240,7 +222,7 @@ pub enum CanonicalVarKind<'tcx> {
     Effect,
 
     /// A "placeholder" that represents "any const".
-    PlaceholderConst(ty::PlaceholderConst<'tcx>, Ty<'tcx>),
+    PlaceholderConst(ty::PlaceholderConst, Ty<'tcx>),
 }
 
 impl<'tcx> CanonicalVarKind<'tcx> {
@@ -379,56 +361,6 @@ impl<'tcx, R> QueryResponse<'tcx, R> {
     }
 }
 
-impl<'tcx, R> Canonical<'tcx, QueryResponse<'tcx, R>> {
-    pub fn is_proven(&self) -> bool {
-        self.value.is_proven()
-    }
-
-    pub fn is_ambiguous(&self) -> bool {
-        !self.is_proven()
-    }
-}
-
-impl<'tcx, V> Canonical<'tcx, V> {
-    /// Allows you to map the `value` of a canonical while keeping the
-    /// same set of bound variables.
-    ///
-    /// **WARNING:** This function is very easy to mis-use, hence the
-    /// name!  In particular, the new value `W` must use all **the
-    /// same type/region variables** in **precisely the same order**
-    /// as the original! (The ordering is defined by the
-    /// `TypeFoldable` implementation of the type in question.)
-    ///
-    /// An example of a **correct** use of this:
-    ///
-    /// ```rust,ignore (not real code)
-    /// let a: Canonical<'_, T> = ...;
-    /// let b: Canonical<'_, (T,)> = a.unchecked_map(|v| (v, ));
-    /// ```
-    ///
-    /// An example of an **incorrect** use of this:
-    ///
-    /// ```rust,ignore (not real code)
-    /// let a: Canonical<'tcx, T> = ...;
-    /// let ty: Ty<'tcx> = ...;
-    /// let b: Canonical<'tcx, (T, Ty<'tcx>)> = a.unchecked_map(|v| (v, ty));
-    /// ```
-    pub fn unchecked_map<W>(self, map_op: impl FnOnce(V) -> W) -> Canonical<'tcx, W> {
-        let Canonical { max_universe, variables, value } = self;
-        Canonical { max_universe, variables, value: map_op(value) }
-    }
-
-    /// Allows you to map the `value` of a canonical while keeping the same set of
-    /// bound variables.
-    ///
-    /// **WARNING:** This function is very easy to mis-use, hence the name! See
-    /// the comment of [Canonical::unchecked_map] for more details.
-    pub fn unchecked_rebind<W>(self, value: W) -> Canonical<'tcx, W> {
-        let Canonical { max_universe, variables, value: _ } = self;
-        Canonical { max_universe, variables, value }
-    }
-}
-
 pub type QueryOutlivesConstraint<'tcx> =
     (ty::OutlivesPredicate<GenericArg<'tcx>, Region<'tcx>>, ConstraintCategory<'tcx>);
 
diff --git a/compiler/rustc_middle/src/infer/unify_key.rs b/compiler/rustc_middle/src/infer/unify_key.rs
index 7ca964759..041a63776 100644
--- a/compiler/rustc_middle/src/infer/unify_key.rs
+++ b/compiler/rustc_middle/src/infer/unify_key.rs
@@ -141,18 +141,30 @@ pub struct ConstVarValue<'tcx> {
     pub val: ConstVariableValue<'tcx>,
 }
 
-impl<'tcx> UnifyKey for ty::ConstVid<'tcx> {
+#[derive(PartialEq, Copy, Clone, Debug)]
+pub struct ConstVidKey<'tcx> {
+    pub vid: ty::ConstVid,
+    pub phantom: PhantomData<ty::Const<'tcx>>,
+}
+
+impl<'tcx> From<ty::ConstVid> for ConstVidKey<'tcx> {
+    fn from(vid: ty::ConstVid) -> Self {
+        ConstVidKey { vid, phantom: PhantomData }
+    }
+}
+
+impl<'tcx> UnifyKey for ConstVidKey<'tcx> {
     type Value = ConstVarValue<'tcx>;
     #[inline]
     fn index(&self) -> u32 {
-        self.index
+        self.vid.as_u32()
     }
     #[inline]
     fn from_index(i: u32) -> Self {
-        ty::ConstVid { index: i, phantom: PhantomData }
+        ConstVidKey::from(ty::ConstVid::from_u32(i))
     }
     fn tag() -> &'static str {
-        "ConstVid"
+        "ConstVidKey"
     }
 }
 
@@ -224,17 +236,29 @@ impl<'tcx> UnifyValue for EffectVarValue<'tcx> {
     }
 }
 
-impl<'tcx> UnifyKey for ty::EffectVid<'tcx> {
+#[derive(PartialEq, Copy, Clone, Debug)]
+pub struct EffectVidKey<'tcx> {
+    pub vid: ty::EffectVid,
+    pub phantom: PhantomData<EffectVarValue<'tcx>>,
+}
+
+impl<'tcx> From<ty::EffectVid> for EffectVidKey<'tcx> {
+    fn from(vid: ty::EffectVid) -> Self {
+        EffectVidKey { vid, phantom: PhantomData }
+    }
+}
+
+impl<'tcx> UnifyKey for EffectVidKey<'tcx> {
     type Value = Option<EffectVarValue<'tcx>>;
     #[inline]
     fn index(&self) -> u32 {
-        self.index
+        self.vid.as_u32()
     }
     #[inline]
     fn from_index(i: u32) -> Self {
-        ty::EffectVid { index: i, phantom: PhantomData }
+        EffectVidKey::from(ty::EffectVid::from_u32(i))
     }
     fn tag() -> &'static str {
-        "EffectVid"
+        "EffectVidKey"
     }
 }