diff --git a/compiler/rustc_infer/src/infer/canonical/canonicalizer.rs b/compiler/rustc_infer/src/infer/canonical/canonicalizer.rs
index a1a0926cd8188..26ecaebe97f2d 100644
--- a/compiler/rustc_infer/src/infer/canonical/canonicalizer.rs
+++ b/compiler/rustc_infer/src/infer/canonical/canonicalizer.rs
@@ -17,8 +17,7 @@ use tracing::debug;
 
 use crate::infer::InferCtxt;
 use crate::infer::canonical::{
-    Canonical, CanonicalQueryInput, CanonicalTyVarKind, CanonicalVarInfo, CanonicalVarKind,
-    OriginalQueryValues,
+    Canonical, CanonicalQueryInput, CanonicalTyVarKind, CanonicalVarKind, OriginalQueryValues,
 };
 
 impl<'tcx> InferCtxt<'tcx> {
@@ -174,10 +173,8 @@ impl CanonicalizeMode for CanonicalizeQueryResponse {
         match r.kind() {
             ty::ReLateParam(_) | ty::ReErased | ty::ReStatic | ty::ReEarlyParam(..) => r,
 
-            ty::RePlaceholder(placeholder) => canonicalizer.canonical_var_for_region(
-                CanonicalVarInfo { kind: CanonicalVarKind::PlaceholderRegion(placeholder) },
-                r,
-            ),
+            ty::RePlaceholder(placeholder) => canonicalizer
+                .canonical_var_for_region(CanonicalVarKind::PlaceholderRegion(placeholder), r),
 
             ty::ReVar(vid) => {
                 let universe = infcx
@@ -186,10 +183,7 @@ impl CanonicalizeMode for CanonicalizeQueryResponse {
                     .unwrap_region_constraints()
                     .probe_value(vid)
                     .unwrap_err();
-                canonicalizer.canonical_var_for_region(
-                    CanonicalVarInfo { kind: CanonicalVarKind::Region(universe) },
-                    r,
-                )
+                canonicalizer.canonical_var_for_region(CanonicalVarKind::Region(universe), r)
             }
 
             _ => {
@@ -294,7 +288,7 @@ struct Canonicalizer<'cx, 'tcx> {
     /// Set to `None` to disable the resolution of inference variables.
     infcx: Option<&'cx InferCtxt<'tcx>>,
     tcx: TyCtxt<'tcx>,
-    variables: SmallVec<[CanonicalVarInfo<'tcx>; 8]>,
+    variables: SmallVec<[CanonicalVarKind<'tcx>; 8]>,
     query_state: &'cx mut OriginalQueryValues<'tcx>,
     // Note that indices is only used once `var_values` is big enough to be
     // heap-allocated.
@@ -368,9 +362,7 @@ impl<'cx, 'tcx> TypeFolder<TyCtxt<'tcx>> for Canonicalizer<'cx, 'tcx> {
                             ui = ty::UniverseIndex::ROOT;
                         }
                         self.canonicalize_ty_var(
-                            CanonicalVarInfo {
-                                kind: CanonicalVarKind::Ty(CanonicalTyVarKind::General(ui)),
-                            },
+                            CanonicalVarKind::Ty(CanonicalTyVarKind::General(ui)),
                             t,
                         )
                     }
@@ -382,10 +374,7 @@ impl<'cx, 'tcx> TypeFolder<TyCtxt<'tcx>> for Canonicalizer<'cx, 'tcx> {
                 if nt != t {
                     return self.fold_ty(nt);
                 } else {
-                    self.canonicalize_ty_var(
-                        CanonicalVarInfo { kind: CanonicalVarKind::Ty(CanonicalTyVarKind::Int) },
-                        t,
-                    )
+                    self.canonicalize_ty_var(CanonicalVarKind::Ty(CanonicalTyVarKind::Int), t)
                 }
             }
             ty::Infer(ty::FloatVar(vid)) => {
@@ -393,10 +382,7 @@ impl<'cx, 'tcx> TypeFolder<TyCtxt<'tcx>> for Canonicalizer<'cx, 'tcx> {
                 if nt != t {
                     return self.fold_ty(nt);
                 } else {
-                    self.canonicalize_ty_var(
-                        CanonicalVarInfo { kind: CanonicalVarKind::Ty(CanonicalTyVarKind::Float) },
-                        t,
-                    )
+                    self.canonicalize_ty_var(CanonicalVarKind::Ty(CanonicalTyVarKind::Float), t)
                 }
             }
 
@@ -408,10 +394,7 @@ impl<'cx, 'tcx> TypeFolder<TyCtxt<'tcx>> for Canonicalizer<'cx, 'tcx> {
                 if !self.canonicalize_mode.preserve_universes() {
                     placeholder.universe = ty::UniverseIndex::ROOT;
                 }
-                self.canonicalize_ty_var(
-                    CanonicalVarInfo { kind: CanonicalVarKind::PlaceholderTy(placeholder) },
-                    t,
-                )
+                self.canonicalize_ty_var(CanonicalVarKind::PlaceholderTy(placeholder), t)
             }
 
             ty::Bound(debruijn, _) => {
@@ -483,10 +466,7 @@ impl<'cx, 'tcx> TypeFolder<TyCtxt<'tcx>> for Canonicalizer<'cx, 'tcx> {
                             // FIXME: perf problem described in #55921.
                             ui = ty::UniverseIndex::ROOT;
                         }
-                        return self.canonicalize_const_var(
-                            CanonicalVarInfo { kind: CanonicalVarKind::Const(ui) },
-                            ct,
-                        );
+                        return self.canonicalize_const_var(CanonicalVarKind::Const(ui), ct);
                     }
                 }
             }
@@ -501,10 +481,8 @@ impl<'cx, 'tcx> TypeFolder<TyCtxt<'tcx>> for Canonicalizer<'cx, 'tcx> {
                 }
             }
             ty::ConstKind::Placeholder(placeholder) => {
-                return self.canonicalize_const_var(
-                    CanonicalVarInfo { kind: CanonicalVarKind::PlaceholderConst(placeholder) },
-                    ct,
-                );
+                return self
+                    .canonicalize_const_var(CanonicalVarKind::PlaceholderConst(placeholder), ct);
             }
             _ => {}
         }
@@ -595,7 +573,7 @@ impl<'cx, 'tcx> Canonicalizer<'cx, 'tcx> {
         debug_assert!(!out_value.has_infer() && !out_value.has_placeholders());
 
         let canonical_variables =
-            tcx.mk_canonical_var_infos(&canonicalizer.universe_canonicalized_variables());
+            tcx.mk_canonical_var_kinds(&canonicalizer.universe_canonicalized_variables());
 
         let max_universe = canonical_variables
             .iter()
@@ -610,18 +588,22 @@ impl<'cx, 'tcx> Canonicalizer<'cx, 'tcx> {
     /// or returns an existing variable if `kind` has already been
     /// seen. `kind` is expected to be an unbound variable (or
     /// potentially a free region).
-    fn canonical_var(&mut self, info: CanonicalVarInfo<'tcx>, kind: GenericArg<'tcx>) -> BoundVar {
+    fn canonical_var(
+        &mut self,
+        var_kind: CanonicalVarKind<'tcx>,
+        value: GenericArg<'tcx>,
+    ) -> BoundVar {
         let Canonicalizer { variables, query_state, indices, .. } = self;
 
         let var_values = &mut query_state.var_values;
 
-        let universe = info.universe();
+        let universe = var_kind.universe();
         if universe != ty::UniverseIndex::ROOT {
             assert!(self.canonicalize_mode.preserve_universes());
 
             // Insert universe into the universe map. To preserve the order of the
             // universes in the value being canonicalized, we don't update the
-            // universe in `info` until we have finished canonicalizing.
+            // universe in `var_kind` until we have finished canonicalizing.
             match query_state.universe_map.binary_search(&universe) {
                 Err(idx) => query_state.universe_map.insert(idx, universe),
                 Ok(_) => {}
@@ -636,14 +618,14 @@ impl<'cx, 'tcx> Canonicalizer<'cx, 'tcx> {
         if !var_values.spilled() {
             // `var_values` is stack-allocated. `indices` isn't used yet. Do a
             // direct linear search of `var_values`.
-            if let Some(idx) = var_values.iter().position(|&k| k == kind) {
+            if let Some(idx) = var_values.iter().position(|&v| v == value) {
                 // `kind` is already present in `var_values`.
                 BoundVar::new(idx)
             } else {
                 // `kind` isn't present in `var_values`. Append it. Likewise
-                // for `info` and `variables`.
-                variables.push(info);
-                var_values.push(kind);
+                // for `var_kind` and `variables`.
+                variables.push(var_kind);
+                var_values.push(value);
                 assert_eq!(variables.len(), var_values.len());
 
                 // If `var_values` has become big enough to be heap-allocated,
@@ -653,7 +635,7 @@ impl<'cx, 'tcx> Canonicalizer<'cx, 'tcx> {
                     *indices = var_values
                         .iter()
                         .enumerate()
-                        .map(|(i, &kind)| (kind, BoundVar::new(i)))
+                        .map(|(i, &value)| (value, BoundVar::new(i)))
                         .collect();
                 }
                 // The cv is the index of the appended element.
@@ -661,9 +643,9 @@ impl<'cx, 'tcx> Canonicalizer<'cx, 'tcx> {
             }
         } else {
             // `var_values` is large. Do a hashmap search via `indices`.
-            *indices.entry(kind).or_insert_with(|| {
-                variables.push(info);
-                var_values.push(kind);
+            *indices.entry(value).or_insert_with(|| {
+                variables.push(var_kind);
+                var_values.push(value);
                 assert_eq!(variables.len(), var_values.len());
                 BoundVar::new(variables.len() - 1)
             })
@@ -673,7 +655,7 @@ impl<'cx, 'tcx> Canonicalizer<'cx, 'tcx> {
     /// Replaces the universe indexes used in `var_values` with their index in
     /// `query_state.universe_map`. This minimizes the maximum universe used in
     /// the canonicalized value.
-    fn universe_canonicalized_variables(self) -> SmallVec<[CanonicalVarInfo<'tcx>; 8]> {
+    fn universe_canonicalized_variables(self) -> SmallVec<[CanonicalVarKind<'tcx>; 8]> {
         if self.query_state.universe_map.len() == 1 {
             return self.variables;
         }
@@ -688,37 +670,33 @@ impl<'cx, 'tcx> Canonicalizer<'cx, 'tcx> {
 
         self.variables
             .iter()
-            .map(|v| CanonicalVarInfo {
-                kind: match v.kind {
-                    CanonicalVarKind::Ty(CanonicalTyVarKind::Int | CanonicalTyVarKind::Float) => {
-                        return *v;
-                    }
-                    CanonicalVarKind::Ty(CanonicalTyVarKind::General(u)) => {
-                        CanonicalVarKind::Ty(CanonicalTyVarKind::General(reverse_universe_map[&u]))
-                    }
-                    CanonicalVarKind::Region(u) => {
-                        CanonicalVarKind::Region(reverse_universe_map[&u])
-                    }
-                    CanonicalVarKind::Const(u) => CanonicalVarKind::Const(reverse_universe_map[&u]),
-                    CanonicalVarKind::PlaceholderTy(placeholder) => {
-                        CanonicalVarKind::PlaceholderTy(ty::Placeholder {
-                            universe: reverse_universe_map[&placeholder.universe],
-                            ..placeholder
-                        })
-                    }
-                    CanonicalVarKind::PlaceholderRegion(placeholder) => {
-                        CanonicalVarKind::PlaceholderRegion(ty::Placeholder {
-                            universe: reverse_universe_map[&placeholder.universe],
-                            ..placeholder
-                        })
-                    }
-                    CanonicalVarKind::PlaceholderConst(placeholder) => {
-                        CanonicalVarKind::PlaceholderConst(ty::Placeholder {
-                            universe: reverse_universe_map[&placeholder.universe],
-                            ..placeholder
-                        })
-                    }
-                },
+            .map(|&kind| match kind {
+                CanonicalVarKind::Ty(CanonicalTyVarKind::Int | CanonicalTyVarKind::Float) => {
+                    return kind;
+                }
+                CanonicalVarKind::Ty(CanonicalTyVarKind::General(u)) => {
+                    CanonicalVarKind::Ty(CanonicalTyVarKind::General(reverse_universe_map[&u]))
+                }
+                CanonicalVarKind::Region(u) => CanonicalVarKind::Region(reverse_universe_map[&u]),
+                CanonicalVarKind::Const(u) => CanonicalVarKind::Const(reverse_universe_map[&u]),
+                CanonicalVarKind::PlaceholderTy(placeholder) => {
+                    CanonicalVarKind::PlaceholderTy(ty::Placeholder {
+                        universe: reverse_universe_map[&placeholder.universe],
+                        ..placeholder
+                    })
+                }
+                CanonicalVarKind::PlaceholderRegion(placeholder) => {
+                    CanonicalVarKind::PlaceholderRegion(ty::Placeholder {
+                        universe: reverse_universe_map[&placeholder.universe],
+                        ..placeholder
+                    })
+                }
+                CanonicalVarKind::PlaceholderConst(placeholder) => {
+                    CanonicalVarKind::PlaceholderConst(ty::Placeholder {
+                        universe: reverse_universe_map[&placeholder.universe],
+                        ..placeholder
+                    })
+                }
             })
             .collect()
     }
@@ -740,20 +718,17 @@ impl<'cx, 'tcx> Canonicalizer<'cx, 'tcx> {
         &mut self,
         r: ty::Region<'tcx>,
     ) -> ty::Region<'tcx> {
-        self.canonical_var_for_region(
-            CanonicalVarInfo { kind: CanonicalVarKind::Region(ty::UniverseIndex::ROOT) },
-            r,
-        )
+        self.canonical_var_for_region(CanonicalVarKind::Region(ty::UniverseIndex::ROOT), r)
     }
 
     /// Creates a canonical variable (with the given `info`)
     /// representing the region `r`; return a region referencing it.
     fn canonical_var_for_region(
         &mut self,
-        info: CanonicalVarInfo<'tcx>,
+        var_kind: CanonicalVarKind<'tcx>,
         r: ty::Region<'tcx>,
     ) -> ty::Region<'tcx> {
-        let var = self.canonical_var(info, r.into());
+        let var = self.canonical_var(var_kind, r.into());
         let br = ty::BoundRegion { var, kind: ty::BoundRegionKind::Anon };
         ty::Region::new_bound(self.cx(), self.binder_index, br)
     }
@@ -762,9 +737,13 @@ impl<'cx, 'tcx> Canonicalizer<'cx, 'tcx> {
     /// if `ty_var` is bound to anything; if so, canonicalize
     /// *that*. Otherwise, create a new canonical variable for
     /// `ty_var`.
-    fn canonicalize_ty_var(&mut self, info: CanonicalVarInfo<'tcx>, ty_var: Ty<'tcx>) -> Ty<'tcx> {
+    fn canonicalize_ty_var(
+        &mut self,
+        var_kind: CanonicalVarKind<'tcx>,
+        ty_var: Ty<'tcx>,
+    ) -> Ty<'tcx> {
         debug_assert!(!self.infcx.is_some_and(|infcx| ty_var != infcx.shallow_resolve(ty_var)));
-        let var = self.canonical_var(info, ty_var.into());
+        let var = self.canonical_var(var_kind, ty_var.into());
         Ty::new_bound(self.tcx, self.binder_index, var.into())
     }
 
@@ -774,13 +753,13 @@ impl<'cx, 'tcx> Canonicalizer<'cx, 'tcx> {
     /// `const_var`.
     fn canonicalize_const_var(
         &mut self,
-        info: CanonicalVarInfo<'tcx>,
-        const_var: ty::Const<'tcx>,
+        var_kind: CanonicalVarKind<'tcx>,
+        ct_var: ty::Const<'tcx>,
     ) -> ty::Const<'tcx> {
         debug_assert!(
-            !self.infcx.is_some_and(|infcx| const_var != infcx.shallow_resolve_const(const_var))
+            !self.infcx.is_some_and(|infcx| ct_var != infcx.shallow_resolve_const(ct_var))
         );
-        let var = self.canonical_var(info, const_var.into());
+        let var = self.canonical_var(var_kind, ct_var.into());
         ty::Const::new_bound(self.tcx, self.binder_index, var)
     }
 }
diff --git a/compiler/rustc_infer/src/infer/canonical/mod.rs b/compiler/rustc_infer/src/infer/canonical/mod.rs
index 3be07dbe208f9..5dffedc709968 100644
--- a/compiler/rustc_infer/src/infer/canonical/mod.rs
+++ b/compiler/rustc_infer/src/infer/canonical/mod.rs
@@ -81,14 +81,14 @@ impl<'tcx> InferCtxt<'tcx> {
     fn instantiate_canonical_vars(
         &self,
         span: Span,
-        variables: &List<CanonicalVarInfo<'tcx>>,
+        variables: &List<CanonicalVarKind<'tcx>>,
         universe_map: impl Fn(ty::UniverseIndex) -> ty::UniverseIndex,
     ) -> CanonicalVarValues<'tcx> {
         CanonicalVarValues {
             var_values: self.tcx.mk_args_from_iter(
                 variables
                     .iter()
-                    .map(|info| self.instantiate_canonical_var(span, info, &universe_map)),
+                    .map(|kind| self.instantiate_canonical_var(span, kind, &universe_map)),
             ),
         }
     }
@@ -104,10 +104,10 @@ impl<'tcx> InferCtxt<'tcx> {
     pub fn instantiate_canonical_var(
         &self,
         span: Span,
-        cv_info: CanonicalVarInfo<'tcx>,
+        kind: CanonicalVarKind<'tcx>,
         universe_map: impl Fn(ty::UniverseIndex) -> ty::UniverseIndex,
     ) -> GenericArg<'tcx> {
-        match cv_info.kind {
+        match kind {
             CanonicalVarKind::Ty(ty_kind) => {
                 let ty = match ty_kind {
                     CanonicalTyVarKind::General(ui) => {
diff --git a/compiler/rustc_infer/src/infer/canonical/query_response.rs b/compiler/rustc_infer/src/infer/canonical/query_response.rs
index 1ae864c454f28..ec72e05494bef 100644
--- a/compiler/rustc_infer/src/infer/canonical/query_response.rs
+++ b/compiler/rustc_infer/src/infer/canonical/query_response.rs
@@ -445,17 +445,17 @@ impl<'tcx> InferCtxt<'tcx> {
         // a fresh inference variable.
         let result_args = CanonicalVarValues {
             var_values: self.tcx.mk_args_from_iter(
-                query_response.variables.iter().enumerate().map(|(index, info)| {
-                    if info.universe() != ty::UniverseIndex::ROOT {
+                query_response.variables.iter().enumerate().map(|(index, var_kind)| {
+                    if var_kind.universe() != ty::UniverseIndex::ROOT {
                         // A variable from inside a binder of the query. While ideally these shouldn't
                         // exist at all, we have to deal with them for now.
-                        self.instantiate_canonical_var(cause.span, info, |u| {
+                        self.instantiate_canonical_var(cause.span, var_kind, |u| {
                             universe_map[u.as_usize()]
                         })
-                    } else if info.is_existential() {
+                    } else if var_kind.is_existential() {
                         match opt_values[BoundVar::new(index)] {
                             Some(k) => k,
-                            None => self.instantiate_canonical_var(cause.span, info, |u| {
+                            None => self.instantiate_canonical_var(cause.span, var_kind, |u| {
                                 universe_map[u.as_usize()]
                             }),
                         }
diff --git a/compiler/rustc_middle/src/infer/canonical.rs b/compiler/rustc_middle/src/infer/canonical.rs
index 5b8603744961c..2bbc48b633c85 100644
--- a/compiler/rustc_middle/src/infer/canonical.rs
+++ b/compiler/rustc_middle/src/infer/canonical.rs
@@ -27,7 +27,7 @@ use rustc_data_structures::fx::FxHashMap;
 use rustc_data_structures::sync::Lock;
 use rustc_macros::{HashStable, TypeFoldable, TypeVisitable};
 pub use rustc_type_ir as ir;
-pub use rustc_type_ir::{CanonicalTyVarKind, CanonicalVarKind};
+pub use rustc_type_ir::CanonicalTyVarKind;
 use smallvec::SmallVec;
 
 use crate::mir::ConstraintCategory;
@@ -35,9 +35,9 @@ use crate::ty::{self, GenericArg, List, Ty, TyCtxt, TypeFlags, TypeVisitableExt}
 
 pub type CanonicalQueryInput<'tcx, V> = ir::CanonicalQueryInput<TyCtxt<'tcx>, V>;
 pub type Canonical<'tcx, V> = ir::Canonical<TyCtxt<'tcx>, V>;
-pub type CanonicalVarInfo<'tcx> = ir::CanonicalVarInfo<TyCtxt<'tcx>>;
+pub type CanonicalVarKind<'tcx> = ir::CanonicalVarKind<TyCtxt<'tcx>>;
 pub type CanonicalVarValues<'tcx> = ir::CanonicalVarValues<TyCtxt<'tcx>>;
-pub type CanonicalVarInfos<'tcx> = &'tcx List<CanonicalVarInfo<'tcx>>;
+pub type CanonicalVarKinds<'tcx> = &'tcx List<CanonicalVarKind<'tcx>>;
 
 /// When we canonicalize a value to form a query, we wind up replacing
 /// various parts of it with canonical variables. This struct stores
diff --git a/compiler/rustc_middle/src/ty/codec.rs b/compiler/rustc_middle/src/ty/codec.rs
index 5ff87959a800d..e0f70737add00 100644
--- a/compiler/rustc_middle/src/ty/codec.rs
+++ b/compiler/rustc_middle/src/ty/codec.rs
@@ -18,7 +18,7 @@ use rustc_span::source_map::Spanned;
 use rustc_span::{Span, SpanDecoder, SpanEncoder};
 
 use crate::arena::ArenaAllocatable;
-use crate::infer::canonical::{CanonicalVarInfo, CanonicalVarInfos};
+use crate::infer::canonical::{CanonicalVarKind, CanonicalVarKinds};
 use crate::mir::interpret::{AllocId, ConstAllocation, CtfeProvenance};
 use crate::mir::mono::MonoItem;
 use crate::mir::{self};
@@ -310,11 +310,11 @@ impl<'tcx, D: TyDecoder<'tcx>> Decodable<D> for ty::Region<'tcx> {
     }
 }
 
-impl<'tcx, D: TyDecoder<'tcx>> Decodable<D> for CanonicalVarInfos<'tcx> {
+impl<'tcx, D: TyDecoder<'tcx>> Decodable<D> for CanonicalVarKinds<'tcx> {
     fn decode(decoder: &mut D) -> Self {
         let len = decoder.read_usize();
         decoder.interner().mk_canonical_var_infos_from_iter(
-            (0..len).map::<CanonicalVarInfo<'tcx>, _>(|_| Decodable::decode(decoder)),
+            (0..len).map::<CanonicalVarKind<'tcx>, _>(|_| Decodable::decode(decoder)),
         )
     }
 }
diff --git a/compiler/rustc_middle/src/ty/context.rs b/compiler/rustc_middle/src/ty/context.rs
index c205d53b93f1f..8c915fea950a4 100644
--- a/compiler/rustc_middle/src/ty/context.rs
+++ b/compiler/rustc_middle/src/ty/context.rs
@@ -60,7 +60,7 @@ use tracing::{debug, instrument};
 
 use crate::arena::Arena;
 use crate::dep_graph::{DepGraph, DepKindStruct};
-use crate::infer::canonical::{CanonicalParamEnvCache, CanonicalVarInfo, CanonicalVarInfos};
+use crate::infer::canonical::{CanonicalParamEnvCache, CanonicalVarKind, CanonicalVarKinds};
 use crate::lint::lint_level;
 use crate::metadata::ModChild;
 use crate::middle::codegen_fn_attrs::{CodegenFnAttrs, TargetFeature};
@@ -107,9 +107,12 @@ impl<'tcx> Interner for TyCtxt<'tcx> {
         self.mk_predefined_opaques_in_body(data)
     }
     type LocalDefIds = &'tcx ty::List<LocalDefId>;
-    type CanonicalVars = CanonicalVarInfos<'tcx>;
-    fn mk_canonical_var_infos(self, infos: &[ty::CanonicalVarInfo<Self>]) -> Self::CanonicalVars {
-        self.mk_canonical_var_infos(infos)
+    type CanonicalVarKinds = CanonicalVarKinds<'tcx>;
+    fn mk_canonical_var_kinds(
+        self,
+        kinds: &[ty::CanonicalVarKind<Self>],
+    ) -> Self::CanonicalVarKinds {
+        self.mk_canonical_var_kinds(kinds)
     }
 
     type ExternalConstraints = ExternalConstraints<'tcx>;
@@ -833,7 +836,7 @@ pub struct CtxtInterners<'tcx> {
     const_lists: InternedSet<'tcx, List<ty::Const<'tcx>>>,
     args: InternedSet<'tcx, GenericArgs<'tcx>>,
     type_lists: InternedSet<'tcx, List<Ty<'tcx>>>,
-    canonical_var_infos: InternedSet<'tcx, List<CanonicalVarInfo<'tcx>>>,
+    canonical_var_kinds: InternedSet<'tcx, List<CanonicalVarKind<'tcx>>>,
     region: InternedSet<'tcx, RegionKind<'tcx>>,
     poly_existential_predicates: InternedSet<'tcx, List<PolyExistentialPredicate<'tcx>>>,
     predicate: InternedSet<'tcx, WithCachedTypeInfo<ty::Binder<'tcx, PredicateKind<'tcx>>>>,
@@ -872,7 +875,7 @@ impl<'tcx> CtxtInterners<'tcx> {
             type_lists: InternedSet::with_capacity(N * 4),
             region: InternedSet::with_capacity(N * 4),
             poly_existential_predicates: InternedSet::with_capacity(N / 4),
-            canonical_var_infos: InternedSet::with_capacity(N / 2),
+            canonical_var_kinds: InternedSet::with_capacity(N / 2),
             predicate: InternedSet::with_capacity(N),
             clauses: InternedSet::with_capacity(N),
             projs: InternedSet::with_capacity(N * 4),
@@ -2675,7 +2678,7 @@ slice_interners!(
     const_lists: pub mk_const_list(Const<'tcx>),
     args: pub mk_args(GenericArg<'tcx>),
     type_lists: pub mk_type_list(Ty<'tcx>),
-    canonical_var_infos: pub mk_canonical_var_infos(CanonicalVarInfo<'tcx>),
+    canonical_var_kinds: pub mk_canonical_var_kinds(CanonicalVarKind<'tcx>),
     poly_existential_predicates: intern_poly_existential_predicates(PolyExistentialPredicate<'tcx>),
     projs: pub mk_projs(ProjectionKind),
     place_elems: pub mk_place_elems(PlaceElem<'tcx>),
@@ -3055,9 +3058,9 @@ impl<'tcx> TyCtxt<'tcx> {
     pub fn mk_canonical_var_infos_from_iter<I, T>(self, iter: I) -> T::Output
     where
         I: Iterator<Item = T>,
-        T: CollectAndApply<CanonicalVarInfo<'tcx>, &'tcx List<CanonicalVarInfo<'tcx>>>,
+        T: CollectAndApply<CanonicalVarKind<'tcx>, &'tcx List<CanonicalVarKind<'tcx>>>,
     {
-        T::collect_and_apply(iter, |xs| self.mk_canonical_var_infos(xs))
+        T::collect_and_apply(iter, |xs| self.mk_canonical_var_kinds(xs))
     }
 
     pub fn mk_place_elems_from_iter<I, T>(self, iter: I) -> T::Output
diff --git a/compiler/rustc_next_trait_solver/src/canonicalizer.rs b/compiler/rustc_next_trait_solver/src/canonicalizer.rs
index bbb4a162027dc..93b8940ee37d8 100644
--- a/compiler/rustc_next_trait_solver/src/canonicalizer.rs
+++ b/compiler/rustc_next_trait_solver/src/canonicalizer.rs
@@ -4,8 +4,8 @@ use rustc_type_ir::data_structures::{HashMap, ensure_sufficient_stack};
 use rustc_type_ir::inherent::*;
 use rustc_type_ir::solve::{Goal, QueryInput};
 use rustc_type_ir::{
-    self as ty, Canonical, CanonicalTyVarKind, CanonicalVarInfo, CanonicalVarKind, InferCtxtLike,
-    Interner, TypeFoldable, TypeFolder, TypeSuperFoldable, TypeVisitableExt,
+    self as ty, Canonical, CanonicalTyVarKind, CanonicalVarKind, InferCtxtLike, Interner,
+    TypeFoldable, TypeFolder, TypeSuperFoldable, TypeVisitableExt,
 };
 
 use crate::delegate::SolverDelegate;
@@ -50,7 +50,7 @@ pub struct Canonicalizer<'a, D: SolverDelegate<Interner = I>, I: Interner> {
 
     // Mutable fields.
     variables: &'a mut Vec<I::GenericArg>,
-    primitive_var_infos: Vec<CanonicalVarInfo<I>>,
+    var_kinds: Vec<CanonicalVarKind<I>>,
     variable_lookup_table: HashMap<I::GenericArg, usize>,
     binder_index: ty::DebruijnIndex,
 
@@ -73,7 +73,7 @@ impl<'a, D: SolverDelegate<Interner = I>, I: Interner> Canonicalizer<'a, D, I> {
 
             variables,
             variable_lookup_table: Default::default(),
-            primitive_var_infos: Vec::new(),
+            var_kinds: Vec::new(),
             binder_index: ty::INNERMOST,
 
             cache: Default::default(),
@@ -106,7 +106,7 @@ impl<'a, D: SolverDelegate<Interner = I>, I: Interner> Canonicalizer<'a, D, I> {
 
             variables,
             variable_lookup_table: Default::default(),
-            primitive_var_infos: Vec::new(),
+            var_kinds: Vec::new(),
             binder_index: ty::INNERMOST,
 
             cache: Default::default(),
@@ -123,7 +123,7 @@ impl<'a, D: SolverDelegate<Interner = I>, I: Interner> Canonicalizer<'a, D, I> {
             // We're able to reuse the `variable_lookup_table` as whether or not
             // it already contains an entry for `'static` does not matter.
             variable_lookup_table: env_canonicalizer.variable_lookup_table,
-            primitive_var_infos: env_canonicalizer.primitive_var_infos,
+            var_kinds: env_canonicalizer.var_kinds,
             binder_index: ty::INNERMOST,
 
             // We do not reuse the cache as it may contain entries whose canonicalized
@@ -149,7 +149,7 @@ impl<'a, D: SolverDelegate<Interner = I>, I: Interner> Canonicalizer<'a, D, I> {
     fn get_or_insert_bound_var(
         &mut self,
         arg: impl Into<I::GenericArg>,
-        canonical_var_info: CanonicalVarInfo<I>,
+        kind: CanonicalVarKind<I>,
     ) -> ty::BoundVar {
         // FIXME: 16 is made up and arbitrary. We should look at some
         // perf data here.
@@ -162,14 +162,14 @@ impl<'a, D: SolverDelegate<Interner = I>, I: Interner> Canonicalizer<'a, D, I> {
             *self.variable_lookup_table.entry(arg).or_insert_with(|| {
                 let var = self.variables.len();
                 self.variables.push(arg);
-                self.primitive_var_infos.push(canonical_var_info);
+                self.var_kinds.push(kind);
                 var
             })
         } else {
             self.variables.iter().position(|&v| v == arg).unwrap_or_else(|| {
                 let var = self.variables.len();
                 self.variables.push(arg);
-                self.primitive_var_infos.push(canonical_var_info);
+                self.var_kinds.push(kind);
                 var
             })
         };
@@ -177,8 +177,8 @@ impl<'a, D: SolverDelegate<Interner = I>, I: Interner> Canonicalizer<'a, D, I> {
         ty::BoundVar::from(idx)
     }
 
-    fn finalize(self) -> (ty::UniverseIndex, I::CanonicalVars) {
-        let mut var_infos = self.primitive_var_infos;
+    fn finalize(self) -> (ty::UniverseIndex, I::CanonicalVarKinds) {
+        let mut var_kinds = self.var_kinds;
         // See the rustc-dev-guide section about how we deal with universes
         // during canonicalization in the new solver.
         match self.canonicalize_mode {
@@ -192,25 +192,25 @@ impl<'a, D: SolverDelegate<Interner = I>, I: Interner> Canonicalizer<'a, D, I> {
             // information for placeholders and inference variables created inside
             // of the query.
             CanonicalizeMode::Response { max_input_universe } => {
-                for var in var_infos.iter_mut() {
+                for var in var_kinds.iter_mut() {
                     let uv = var.universe();
                     let new_uv = ty::UniverseIndex::from(
                         uv.index().saturating_sub(max_input_universe.index()),
                     );
                     *var = var.with_updated_universe(new_uv);
                 }
-                let max_universe = var_infos
+                let max_universe = var_kinds
                     .iter()
-                    .map(|info| info.universe())
+                    .map(|kind| kind.universe())
                     .max()
                     .unwrap_or(ty::UniverseIndex::ROOT);
 
-                let var_infos = self.delegate.cx().mk_canonical_var_infos(&var_infos);
-                return (max_universe, var_infos);
+                let var_kinds = self.delegate.cx().mk_canonical_var_kinds(&var_kinds);
+                return (max_universe, var_kinds);
             }
         }
 
-        // Given a `var_infos` with existentials `En` and universals `Un` in
+        // Given a `var_kinds` with existentials `En` and universals `Un` in
         // universes `n`, this algorithm compresses them in place so that:
         //
         // - the new universe indices are as small as possible
@@ -219,12 +219,12 @@ impl<'a, D: SolverDelegate<Interner = I>, I: Interner> Canonicalizer<'a, D, I> {
         //   2. put a placeholder in the same universe as an existential which cannot name it
         //
         // Let's walk through an example:
-        // - var_infos: [E0, U1, E5, U2, E2, E6, U6], curr_compressed_uv: 0, next_orig_uv: 0
-        // - var_infos: [E0, U1, E5, U2, E2, E6, U6], curr_compressed_uv: 0, next_orig_uv: 1
-        // - var_infos: [E0, U1, E5, U2, E2, E6, U6], curr_compressed_uv: 1, next_orig_uv: 2
-        // - var_infos: [E0, U1, E5, U1, E1, E6, U6], curr_compressed_uv: 1, next_orig_uv: 5
-        // - var_infos: [E0, U1, E2, U1, E1, E6, U6], curr_compressed_uv: 2, next_orig_uv: 6
-        // - var_infos: [E0, U1, E1, U1, E1, E3, U3], curr_compressed_uv: 2, next_orig_uv: -
+        // - var_kinds: [E0, U1, E5, U2, E2, E6, U6], curr_compressed_uv: 0, next_orig_uv: 0
+        // - var_kinds: [E0, U1, E5, U2, E2, E6, U6], curr_compressed_uv: 0, next_orig_uv: 1
+        // - var_kinds: [E0, U1, E5, U2, E2, E6, U6], curr_compressed_uv: 1, next_orig_uv: 2
+        // - var_kinds: [E0, U1, E5, U1, E1, E6, U6], curr_compressed_uv: 1, next_orig_uv: 5
+        // - var_kinds: [E0, U1, E2, U1, E1, E6, U6], curr_compressed_uv: 2, next_orig_uv: 6
+        // - var_kinds: [E0, U1, E1, U1, E1, E3, U3], curr_compressed_uv: 2, next_orig_uv: -
         //
         // This algorithm runs in `O(mn)` where `n` is the number of different universes and
         // `m` the number of variables. This should be fine as both are expected to be small.
@@ -232,7 +232,7 @@ impl<'a, D: SolverDelegate<Interner = I>, I: Interner> Canonicalizer<'a, D, I> {
         let mut existential_in_new_uv = None;
         let mut next_orig_uv = Some(ty::UniverseIndex::ROOT);
         while let Some(orig_uv) = next_orig_uv.take() {
-            let mut update_uv = |var: &mut CanonicalVarInfo<I>, orig_uv, is_existential| {
+            let mut update_uv = |var: &mut CanonicalVarKind<I>, orig_uv, is_existential| {
                 let uv = var.universe();
                 match uv.cmp(&orig_uv) {
                     Ordering::Less => (), // Already updated
@@ -284,7 +284,7 @@ impl<'a, D: SolverDelegate<Interner = I>, I: Interner> Canonicalizer<'a, D, I> {
             // Whenever we compress the universe of a placeholder, no existential with
             // an already compressed universe can name that placeholder.
             for is_existential in [false, true] {
-                for var in var_infos.iter_mut() {
+                for var in var_kinds.iter_mut() {
                     // We simply put all regions from the input into the highest
                     // compressed universe, so we only deal with them at the end.
                     if !var.is_region() {
@@ -298,7 +298,7 @@ impl<'a, D: SolverDelegate<Interner = I>, I: Interner> Canonicalizer<'a, D, I> {
 
         // We put all regions into a separate universe.
         let mut first_region = true;
-        for var in var_infos.iter_mut() {
+        for var in var_kinds.iter_mut() {
             if var.is_region() {
                 if first_region {
                     first_region = false;
@@ -309,8 +309,8 @@ impl<'a, D: SolverDelegate<Interner = I>, I: Interner> Canonicalizer<'a, D, I> {
             }
         }
 
-        let var_infos = self.delegate.cx().mk_canonical_var_infos(&var_infos);
-        (curr_compressed_uv, var_infos)
+        let var_kinds = self.delegate.cx().mk_canonical_var_kinds(&var_kinds);
+        (curr_compressed_uv, var_kinds)
     }
 
     fn cached_fold_ty(&mut self, t: I::Ty) -> I::Ty {
@@ -391,7 +391,7 @@ impl<'a, D: SolverDelegate<Interner = I>, I: Interner> Canonicalizer<'a, D, I> {
             }
         };
 
-        let var = self.get_or_insert_bound_var(t, CanonicalVarInfo { kind });
+        let var = self.get_or_insert_bound_var(t, kind);
 
         Ty::new_anon_bound(self.cx(), self.binder_index, var)
     }
@@ -475,7 +475,7 @@ impl<D: SolverDelegate<Interner = I>, I: Interner> TypeFolder<I> for Canonicaliz
             }
         };
 
-        let var = self.get_or_insert_bound_var(r, CanonicalVarInfo { kind });
+        let var = self.get_or_insert_bound_var(r, kind);
 
         Region::new_anon_bound(self.cx(), self.binder_index, var)
     }
@@ -525,7 +525,7 @@ impl<D: SolverDelegate<Interner = I>, I: Interner> TypeFolder<I> for Canonicaliz
             | ty::ConstKind::Expr(_) => return c.super_fold_with(self),
         };
 
-        let var = self.get_or_insert_bound_var(c, CanonicalVarInfo { kind });
+        let var = self.get_or_insert_bound_var(c, kind);
 
         Const::new_anon_bound(self.cx(), self.binder_index, var)
     }
diff --git a/compiler/rustc_next_trait_solver/src/delegate.rs b/compiler/rustc_next_trait_solver/src/delegate.rs
index bb923612cffc4..32dc85b3e6a71 100644
--- a/compiler/rustc_next_trait_solver/src/delegate.rs
+++ b/compiler/rustc_next_trait_solver/src/delegate.rs
@@ -61,7 +61,7 @@ pub trait SolverDelegate: Deref<Target = Self::Infcx> + Sized {
 
     fn instantiate_canonical_var_with_infer(
         &self,
-        cv_info: ty::CanonicalVarInfo<Self::Interner>,
+        kind: ty::CanonicalVarKind<Self::Interner>,
         span: <Self::Interner as Interner>::Span,
         universe_map: impl Fn(ty::UniverseIndex) -> ty::UniverseIndex,
     ) -> <Self::Interner as Interner>::GenericArg;
diff --git a/compiler/rustc_next_trait_solver/src/solve/eval_ctxt/canonical.rs b/compiler/rustc_next_trait_solver/src/solve/eval_ctxt/canonical.rs
index c62f2e2e0e95f..455a178595b29 100644
--- a/compiler/rustc_next_trait_solver/src/solve/eval_ctxt/canonical.rs
+++ b/compiler/rustc_next_trait_solver/src/solve/eval_ctxt/canonical.rs
@@ -360,15 +360,15 @@ where
         }
 
         let var_values = delegate.cx().mk_args_from_iter(
-            response.variables.iter().enumerate().map(|(index, info)| {
-                if info.universe() != ty::UniverseIndex::ROOT {
+            response.variables.iter().enumerate().map(|(index, var_kind)| {
+                if var_kind.universe() != ty::UniverseIndex::ROOT {
                     // A variable from inside a binder of the query. While ideally these shouldn't
                     // exist at all (see the FIXME at the start of this method), we have to deal with
                     // them for now.
-                    delegate.instantiate_canonical_var_with_infer(info, span, |idx| {
+                    delegate.instantiate_canonical_var_with_infer(var_kind, span, |idx| {
                         prev_universe + idx.index()
                     })
-                } else if info.is_existential() {
+                } else if var_kind.is_existential() {
                     // As an optimization we sometimes avoid creating a new inference variable here.
                     //
                     // All new inference variables we create start out in the current universe of the caller.
@@ -379,12 +379,13 @@ where
                     if let Some(v) = opt_values[ty::BoundVar::from_usize(index)] {
                         v
                     } else {
-                        delegate.instantiate_canonical_var_with_infer(info, span, |_| prev_universe)
+                        delegate
+                            .instantiate_canonical_var_with_infer(var_kind, span, |_| prev_universe)
                     }
                 } else {
                     // For placeholders which were already part of the input, we simply map this
                     // universal bound variable back the placeholder of the input.
-                    original_values[info.expect_placeholder_index()]
+                    original_values[var_kind.expect_placeholder_index()]
                 }
             }),
         );
diff --git a/compiler/rustc_next_trait_solver/src/solve/eval_ctxt/mod.rs b/compiler/rustc_next_trait_solver/src/solve/eval_ctxt/mod.rs
index 9a4b95903a970..dfabb94ebfc60 100644
--- a/compiler/rustc_next_trait_solver/src/solve/eval_ctxt/mod.rs
+++ b/compiler/rustc_next_trait_solver/src/solve/eval_ctxt/mod.rs
@@ -91,7 +91,7 @@ where
 
     /// The variable info for the `var_values`, only used to make an ambiguous response
     /// with no constraints.
-    variables: I::CanonicalVars,
+    variables: I::CanonicalVarKinds,
 
     /// What kind of goal we're currently computing, see the enum definition
     /// for more info.
diff --git a/compiler/rustc_next_trait_solver/src/solve/mod.rs b/compiler/rustc_next_trait_solver/src/solve/mod.rs
index 8173146e2fe24..2a64180715411 100644
--- a/compiler/rustc_next_trait_solver/src/solve/mod.rs
+++ b/compiler/rustc_next_trait_solver/src/solve/mod.rs
@@ -354,7 +354,7 @@ where
 fn response_no_constraints_raw<I: Interner>(
     cx: I,
     max_universe: ty::UniverseIndex,
-    variables: I::CanonicalVars,
+    variables: I::CanonicalVarKinds,
     certainty: Certainty,
 ) -> CanonicalResponse<I> {
     ty::Canonical {
diff --git a/compiler/rustc_trait_selection/src/solve/delegate.rs b/compiler/rustc_trait_selection/src/solve/delegate.rs
index a60642b953ced..b68a784536604 100644
--- a/compiler/rustc_trait_selection/src/solve/delegate.rs
+++ b/compiler/rustc_trait_selection/src/solve/delegate.rs
@@ -5,7 +5,7 @@ use rustc_hir::LangItem;
 use rustc_hir::def_id::{CRATE_DEF_ID, DefId};
 use rustc_infer::infer::canonical::query_response::make_query_region_constraints;
 use rustc_infer::infer::canonical::{
-    Canonical, CanonicalExt as _, CanonicalQueryInput, CanonicalVarInfo, CanonicalVarValues,
+    Canonical, CanonicalExt as _, CanonicalQueryInput, CanonicalVarKind, CanonicalVarValues,
 };
 use rustc_infer::infer::{InferCtxt, RegionVariableOrigin, SubregionOrigin, TyCtxtInferExt};
 use rustc_infer::traits::solve::Goal;
@@ -190,11 +190,11 @@ impl<'tcx> rustc_next_trait_solver::delegate::SolverDelegate for SolverDelegate<
 
     fn instantiate_canonical_var_with_infer(
         &self,
-        cv_info: CanonicalVarInfo<'tcx>,
+        kind: CanonicalVarKind<'tcx>,
         span: Span,
         universe_map: impl Fn(ty::UniverseIndex) -> ty::UniverseIndex,
     ) -> ty::GenericArg<'tcx> {
-        self.0.instantiate_canonical_var(span, cv_info, universe_map)
+        self.0.instantiate_canonical_var(span, kind, universe_map)
     }
 
     fn add_item_bounds_for_hidden_type(
diff --git a/compiler/rustc_type_ir/src/canonical.rs b/compiler/rustc_type_ir/src/canonical.rs
index 67b67df4b2817..2b1b0617cef6a 100644
--- a/compiler/rustc_type_ir/src/canonical.rs
+++ b/compiler/rustc_type_ir/src/canonical.rs
@@ -41,7 +41,7 @@ pub struct CanonicalQueryInput<I: Interner, V> {
 pub struct Canonical<I: Interner, V> {
     pub value: V,
     pub max_universe: UniverseIndex,
-    pub variables: I::CanonicalVars,
+    pub variables: I::CanonicalVarKinds,
 }
 
 impl<I: Interner, V> Canonical<I, V> {
@@ -89,63 +89,6 @@ impl<I: Interner, V: fmt::Display> fmt::Display for Canonical<I, V> {
 /// a copy of the canonical value in some other inference context,
 /// with fresh inference variables replacing the canonical values.
 #[derive_where(Clone, Copy, Hash, PartialEq, Eq, Debug; I: Interner)]
-#[derive(TypeVisitable_Generic, TypeFoldable_Generic)]
-#[cfg_attr(
-    feature = "nightly",
-    derive(Decodable_NoContext, Encodable_NoContext, HashStable_NoContext)
-)]
-pub struct CanonicalVarInfo<I: Interner> {
-    pub kind: CanonicalVarKind<I>,
-}
-
-impl<I: Interner> CanonicalVarInfo<I> {
-    pub fn universe(self) -> UniverseIndex {
-        self.kind.universe()
-    }
-
-    #[must_use]
-    pub fn with_updated_universe(self, ui: UniverseIndex) -> CanonicalVarInfo<I> {
-        CanonicalVarInfo { kind: self.kind.with_updated_universe(ui) }
-    }
-
-    pub fn is_existential(&self) -> bool {
-        match self.kind {
-            CanonicalVarKind::Ty(_) => true,
-            CanonicalVarKind::PlaceholderTy(_) => false,
-            CanonicalVarKind::Region(_) => true,
-            CanonicalVarKind::PlaceholderRegion(..) => false,
-            CanonicalVarKind::Const(_) => true,
-            CanonicalVarKind::PlaceholderConst(_) => false,
-        }
-    }
-
-    pub fn is_region(&self) -> bool {
-        match self.kind {
-            CanonicalVarKind::Region(_) | CanonicalVarKind::PlaceholderRegion(_) => true,
-            CanonicalVarKind::Ty(_)
-            | CanonicalVarKind::PlaceholderTy(_)
-            | CanonicalVarKind::Const(_)
-            | CanonicalVarKind::PlaceholderConst(_) => false,
-        }
-    }
-
-    pub fn expect_placeholder_index(self) -> usize {
-        match self.kind {
-            CanonicalVarKind::Ty(_) | CanonicalVarKind::Region(_) | CanonicalVarKind::Const(_) => {
-                panic!("expected placeholder: {self:?}")
-            }
-
-            CanonicalVarKind::PlaceholderRegion(placeholder) => placeholder.var().as_usize(),
-            CanonicalVarKind::PlaceholderTy(placeholder) => placeholder.var().as_usize(),
-            CanonicalVarKind::PlaceholderConst(placeholder) => placeholder.var().as_usize(),
-        }
-    }
-}
-
-/// Describes the "kind" of the canonical variable. This is a "kind"
-/// in the type-theory sense of the term -- i.e., a "meta" type system
-/// that analyzes type-like values.
-#[derive_where(Clone, Copy, Hash, PartialEq, Eq, Debug; I: Interner)]
 #[cfg_attr(
     feature = "nightly",
     derive(Decodable_NoContext, Encodable_NoContext, HashStable_NoContext)
@@ -214,6 +157,39 @@ impl<I: Interner> CanonicalVarKind<I> {
             }
         }
     }
+
+    pub fn is_existential(self) -> bool {
+        match self {
+            CanonicalVarKind::Ty(_) => true,
+            CanonicalVarKind::PlaceholderTy(_) => false,
+            CanonicalVarKind::Region(_) => true,
+            CanonicalVarKind::PlaceholderRegion(..) => false,
+            CanonicalVarKind::Const(_) => true,
+            CanonicalVarKind::PlaceholderConst(_) => false,
+        }
+    }
+
+    pub fn is_region(self) -> bool {
+        match self {
+            CanonicalVarKind::Region(_) | CanonicalVarKind::PlaceholderRegion(_) => true,
+            CanonicalVarKind::Ty(_)
+            | CanonicalVarKind::PlaceholderTy(_)
+            | CanonicalVarKind::Const(_)
+            | CanonicalVarKind::PlaceholderConst(_) => false,
+        }
+    }
+
+    pub fn expect_placeholder_index(self) -> usize {
+        match self {
+            CanonicalVarKind::Ty(_) | CanonicalVarKind::Region(_) | CanonicalVarKind::Const(_) => {
+                panic!("expected placeholder: {self:?}")
+            }
+
+            CanonicalVarKind::PlaceholderRegion(placeholder) => placeholder.var().as_usize(),
+            CanonicalVarKind::PlaceholderTy(placeholder) => placeholder.var().as_usize(),
+            CanonicalVarKind::PlaceholderConst(placeholder) => placeholder.var().as_usize(),
+        }
+    }
 }
 
 /// Rust actually has more than one category of type variables;
@@ -306,11 +282,11 @@ impl<I: Interner> CanonicalVarValues<I> {
 
     // Given a list of canonical variables, construct a set of values which are
     // the identity response.
-    pub fn make_identity(cx: I, infos: I::CanonicalVars) -> CanonicalVarValues<I> {
+    pub fn make_identity(cx: I, infos: I::CanonicalVarKinds) -> CanonicalVarValues<I> {
         CanonicalVarValues {
             var_values: cx.mk_args_from_iter(infos.iter().enumerate().map(
-                |(i, info)| -> I::GenericArg {
-                    match info.kind {
+                |(i, kind)| -> I::GenericArg {
+                    match kind {
                         CanonicalVarKind::Ty(_) | CanonicalVarKind::PlaceholderTy(_) => {
                             Ty::new_anon_bound(cx, ty::INNERMOST, ty::BoundVar::from_usize(i))
                                 .into()
diff --git a/compiler/rustc_type_ir/src/interner.rs b/compiler/rustc_type_ir/src/interner.rs
index c10241cfcf0f6..7e88114df460f 100644
--- a/compiler/rustc_type_ir/src/interner.rs
+++ b/compiler/rustc_type_ir/src/interner.rs
@@ -64,13 +64,16 @@ pub trait Interner:
         + TypeVisitable<Self>
         + SliceLike<Item = Self::LocalDefId>;
 
-    type CanonicalVars: Copy
+    type CanonicalVarKinds: Copy
         + Debug
         + Hash
         + Eq
-        + SliceLike<Item = ty::CanonicalVarInfo<Self>>
+        + SliceLike<Item = ty::CanonicalVarKind<Self>>
         + Default;
-    fn mk_canonical_var_infos(self, infos: &[ty::CanonicalVarInfo<Self>]) -> Self::CanonicalVars;
+    fn mk_canonical_var_kinds(
+        self,
+        kinds: &[ty::CanonicalVarKind<Self>],
+    ) -> Self::CanonicalVarKinds;
 
     type ExternalConstraints: Copy
         + Debug
diff --git a/tests/mir-opt/address_of.address_of_reborrow.SimplifyCfg-initial.after.mir b/tests/mir-opt/address_of.address_of_reborrow.SimplifyCfg-initial.after.mir
index 5fc77f95eaf72..8afb6ad250e03 100644
--- a/tests/mir-opt/address_of.address_of_reborrow.SimplifyCfg-initial.after.mir
+++ b/tests/mir-opt/address_of.address_of_reborrow.SimplifyCfg-initial.after.mir
@@ -1,34 +1,34 @@
 // MIR for `address_of_reborrow` after SimplifyCfg-initial
 
 | User Type Annotations
-| 0: user_ty: Canonical { value: Ty(*const ^0), max_universe: U0, variables: [CanonicalVarInfo { kind: Ty(General(U0)) }] }, span: $DIR/address_of.rs:8:10: 8:18, inferred_ty: *const [i32; 10]
-| 1: user_ty: Canonical { value: Ty(*const dyn std::marker::Send), max_universe: U0, variables: [CanonicalVarInfo { kind: Region(U0) }] }, span: $DIR/address_of.rs:10:10: 10:25, inferred_ty: *const dyn std::marker::Send
-| 2: user_ty: Canonical { value: Ty(*const ^0), max_universe: U0, variables: [CanonicalVarInfo { kind: Ty(General(U0)) }] }, span: $DIR/address_of.rs:14:12: 14:20, inferred_ty: *const [i32; 10]
-| 3: user_ty: Canonical { value: Ty(*const ^0), max_universe: U0, variables: [CanonicalVarInfo { kind: Ty(General(U0)) }] }, span: $DIR/address_of.rs:14:12: 14:20, inferred_ty: *const [i32; 10]
+| 0: user_ty: Canonical { value: Ty(*const ^0), max_universe: U0, variables: [Ty(General(U0))] }, span: $DIR/address_of.rs:8:10: 8:18, inferred_ty: *const [i32; 10]
+| 1: user_ty: Canonical { value: Ty(*const dyn std::marker::Send), max_universe: U0, variables: [Region(U0)] }, span: $DIR/address_of.rs:10:10: 10:25, inferred_ty: *const dyn std::marker::Send
+| 2: user_ty: Canonical { value: Ty(*const ^0), max_universe: U0, variables: [Ty(General(U0))] }, span: $DIR/address_of.rs:14:12: 14:20, inferred_ty: *const [i32; 10]
+| 3: user_ty: Canonical { value: Ty(*const ^0), max_universe: U0, variables: [Ty(General(U0))] }, span: $DIR/address_of.rs:14:12: 14:20, inferred_ty: *const [i32; 10]
 | 4: user_ty: Canonical { value: Ty(*const [i32; 10]), max_universe: U0, variables: [] }, span: $DIR/address_of.rs:15:12: 15:28, inferred_ty: *const [i32; 10]
 | 5: user_ty: Canonical { value: Ty(*const [i32; 10]), max_universe: U0, variables: [] }, span: $DIR/address_of.rs:15:12: 15:28, inferred_ty: *const [i32; 10]
-| 6: user_ty: Canonical { value: Ty(*const dyn std::marker::Send), max_universe: U0, variables: [CanonicalVarInfo { kind: Region(U0) }] }, span: $DIR/address_of.rs:16:12: 16:27, inferred_ty: *const dyn std::marker::Send
-| 7: user_ty: Canonical { value: Ty(*const dyn std::marker::Send), max_universe: U0, variables: [CanonicalVarInfo { kind: Region(U0) }] }, span: $DIR/address_of.rs:16:12: 16:27, inferred_ty: *const dyn std::marker::Send
+| 6: user_ty: Canonical { value: Ty(*const dyn std::marker::Send), max_universe: U0, variables: [Region(U0)] }, span: $DIR/address_of.rs:16:12: 16:27, inferred_ty: *const dyn std::marker::Send
+| 7: user_ty: Canonical { value: Ty(*const dyn std::marker::Send), max_universe: U0, variables: [Region(U0)] }, span: $DIR/address_of.rs:16:12: 16:27, inferred_ty: *const dyn std::marker::Send
 | 8: user_ty: Canonical { value: Ty(*const [i32]), max_universe: U0, variables: [] }, span: $DIR/address_of.rs:17:12: 17:24, inferred_ty: *const [i32]
 | 9: user_ty: Canonical { value: Ty(*const [i32]), max_universe: U0, variables: [] }, span: $DIR/address_of.rs:17:12: 17:24, inferred_ty: *const [i32]
-| 10: user_ty: Canonical { value: Ty(*const ^0), max_universe: U0, variables: [CanonicalVarInfo { kind: Ty(General(U0)) }] }, span: $DIR/address_of.rs:19:10: 19:18, inferred_ty: *const [i32; 10]
-| 11: user_ty: Canonical { value: Ty(*const dyn std::marker::Send), max_universe: U0, variables: [CanonicalVarInfo { kind: Region(U0) }] }, span: $DIR/address_of.rs:21:10: 21:25, inferred_ty: *const dyn std::marker::Send
-| 12: user_ty: Canonical { value: Ty(*const ^0), max_universe: U0, variables: [CanonicalVarInfo { kind: Ty(General(U0)) }] }, span: $DIR/address_of.rs:24:12: 24:20, inferred_ty: *const [i32; 10]
-| 13: user_ty: Canonical { value: Ty(*const ^0), max_universe: U0, variables: [CanonicalVarInfo { kind: Ty(General(U0)) }] }, span: $DIR/address_of.rs:24:12: 24:20, inferred_ty: *const [i32; 10]
+| 10: user_ty: Canonical { value: Ty(*const ^0), max_universe: U0, variables: [Ty(General(U0))] }, span: $DIR/address_of.rs:19:10: 19:18, inferred_ty: *const [i32; 10]
+| 11: user_ty: Canonical { value: Ty(*const dyn std::marker::Send), max_universe: U0, variables: [Region(U0)] }, span: $DIR/address_of.rs:21:10: 21:25, inferred_ty: *const dyn std::marker::Send
+| 12: user_ty: Canonical { value: Ty(*const ^0), max_universe: U0, variables: [Ty(General(U0))] }, span: $DIR/address_of.rs:24:12: 24:20, inferred_ty: *const [i32; 10]
+| 13: user_ty: Canonical { value: Ty(*const ^0), max_universe: U0, variables: [Ty(General(U0))] }, span: $DIR/address_of.rs:24:12: 24:20, inferred_ty: *const [i32; 10]
 | 14: user_ty: Canonical { value: Ty(*const [i32; 10]), max_universe: U0, variables: [] }, span: $DIR/address_of.rs:25:12: 25:28, inferred_ty: *const [i32; 10]
 | 15: user_ty: Canonical { value: Ty(*const [i32; 10]), max_universe: U0, variables: [] }, span: $DIR/address_of.rs:25:12: 25:28, inferred_ty: *const [i32; 10]
-| 16: user_ty: Canonical { value: Ty(*const dyn std::marker::Send), max_universe: U0, variables: [CanonicalVarInfo { kind: Region(U0) }] }, span: $DIR/address_of.rs:26:12: 26:27, inferred_ty: *const dyn std::marker::Send
-| 17: user_ty: Canonical { value: Ty(*const dyn std::marker::Send), max_universe: U0, variables: [CanonicalVarInfo { kind: Region(U0) }] }, span: $DIR/address_of.rs:26:12: 26:27, inferred_ty: *const dyn std::marker::Send
+| 16: user_ty: Canonical { value: Ty(*const dyn std::marker::Send), max_universe: U0, variables: [Region(U0)] }, span: $DIR/address_of.rs:26:12: 26:27, inferred_ty: *const dyn std::marker::Send
+| 17: user_ty: Canonical { value: Ty(*const dyn std::marker::Send), max_universe: U0, variables: [Region(U0)] }, span: $DIR/address_of.rs:26:12: 26:27, inferred_ty: *const dyn std::marker::Send
 | 18: user_ty: Canonical { value: Ty(*const [i32]), max_universe: U0, variables: [] }, span: $DIR/address_of.rs:27:12: 27:24, inferred_ty: *const [i32]
 | 19: user_ty: Canonical { value: Ty(*const [i32]), max_universe: U0, variables: [] }, span: $DIR/address_of.rs:27:12: 27:24, inferred_ty: *const [i32]
-| 20: user_ty: Canonical { value: Ty(*mut ^0), max_universe: U0, variables: [CanonicalVarInfo { kind: Ty(General(U0)) }] }, span: $DIR/address_of.rs:29:10: 29:16, inferred_ty: *mut [i32; 10]
-| 21: user_ty: Canonical { value: Ty(*mut dyn std::marker::Send), max_universe: U0, variables: [CanonicalVarInfo { kind: Region(U0) }] }, span: $DIR/address_of.rs:31:10: 31:23, inferred_ty: *mut dyn std::marker::Send
-| 22: user_ty: Canonical { value: Ty(*mut ^0), max_universe: U0, variables: [CanonicalVarInfo { kind: Ty(General(U0)) }] }, span: $DIR/address_of.rs:34:12: 34:18, inferred_ty: *mut [i32; 10]
-| 23: user_ty: Canonical { value: Ty(*mut ^0), max_universe: U0, variables: [CanonicalVarInfo { kind: Ty(General(U0)) }] }, span: $DIR/address_of.rs:34:12: 34:18, inferred_ty: *mut [i32; 10]
+| 20: user_ty: Canonical { value: Ty(*mut ^0), max_universe: U0, variables: [Ty(General(U0))] }, span: $DIR/address_of.rs:29:10: 29:16, inferred_ty: *mut [i32; 10]
+| 21: user_ty: Canonical { value: Ty(*mut dyn std::marker::Send), max_universe: U0, variables: [Region(U0)] }, span: $DIR/address_of.rs:31:10: 31:23, inferred_ty: *mut dyn std::marker::Send
+| 22: user_ty: Canonical { value: Ty(*mut ^0), max_universe: U0, variables: [Ty(General(U0))] }, span: $DIR/address_of.rs:34:12: 34:18, inferred_ty: *mut [i32; 10]
+| 23: user_ty: Canonical { value: Ty(*mut ^0), max_universe: U0, variables: [Ty(General(U0))] }, span: $DIR/address_of.rs:34:12: 34:18, inferred_ty: *mut [i32; 10]
 | 24: user_ty: Canonical { value: Ty(*mut [i32; 10]), max_universe: U0, variables: [] }, span: $DIR/address_of.rs:35:12: 35:26, inferred_ty: *mut [i32; 10]
 | 25: user_ty: Canonical { value: Ty(*mut [i32; 10]), max_universe: U0, variables: [] }, span: $DIR/address_of.rs:35:12: 35:26, inferred_ty: *mut [i32; 10]
-| 26: user_ty: Canonical { value: Ty(*mut dyn std::marker::Send), max_universe: U0, variables: [CanonicalVarInfo { kind: Region(U0) }] }, span: $DIR/address_of.rs:36:12: 36:25, inferred_ty: *mut dyn std::marker::Send
-| 27: user_ty: Canonical { value: Ty(*mut dyn std::marker::Send), max_universe: U0, variables: [CanonicalVarInfo { kind: Region(U0) }] }, span: $DIR/address_of.rs:36:12: 36:25, inferred_ty: *mut dyn std::marker::Send
+| 26: user_ty: Canonical { value: Ty(*mut dyn std::marker::Send), max_universe: U0, variables: [Region(U0)] }, span: $DIR/address_of.rs:36:12: 36:25, inferred_ty: *mut dyn std::marker::Send
+| 27: user_ty: Canonical { value: Ty(*mut dyn std::marker::Send), max_universe: U0, variables: [Region(U0)] }, span: $DIR/address_of.rs:36:12: 36:25, inferred_ty: *mut dyn std::marker::Send
 | 28: user_ty: Canonical { value: Ty(*mut [i32]), max_universe: U0, variables: [] }, span: $DIR/address_of.rs:37:12: 37:22, inferred_ty: *mut [i32]
 | 29: user_ty: Canonical { value: Ty(*mut [i32]), max_universe: U0, variables: [] }, span: $DIR/address_of.rs:37:12: 37:22, inferred_ty: *mut [i32]
 |
diff --git a/tests/mir-opt/building/receiver_ptr_mutability.main.built.after.mir b/tests/mir-opt/building/receiver_ptr_mutability.main.built.after.mir
index 6e349a2a24ff6..744553c7cd266 100644
--- a/tests/mir-opt/building/receiver_ptr_mutability.main.built.after.mir
+++ b/tests/mir-opt/building/receiver_ptr_mutability.main.built.after.mir
@@ -3,8 +3,8 @@
 | User Type Annotations
 | 0: user_ty: Canonical { value: Ty(*mut Test), max_universe: U0, variables: [] }, span: $DIR/receiver_ptr_mutability.rs:15:14: 15:23, inferred_ty: *mut Test
 | 1: user_ty: Canonical { value: Ty(*mut Test), max_universe: U0, variables: [] }, span: $DIR/receiver_ptr_mutability.rs:15:14: 15:23, inferred_ty: *mut Test
-| 2: user_ty: Canonical { value: Ty(&&&&*mut Test), max_universe: U0, variables: [CanonicalVarInfo { kind: Region(U0) }, CanonicalVarInfo { kind: Region(U0) }, CanonicalVarInfo { kind: Region(U0) }, CanonicalVarInfo { kind: Region(U0) }] }, span: $DIR/receiver_ptr_mutability.rs:19:18: 19:31, inferred_ty: &&&&*mut Test
-| 3: user_ty: Canonical { value: Ty(&&&&*mut Test), max_universe: U0, variables: [CanonicalVarInfo { kind: Region(U0) }, CanonicalVarInfo { kind: Region(U0) }, CanonicalVarInfo { kind: Region(U0) }, CanonicalVarInfo { kind: Region(U0) }] }, span: $DIR/receiver_ptr_mutability.rs:19:18: 19:31, inferred_ty: &&&&*mut Test
+| 2: user_ty: Canonical { value: Ty(&&&&*mut Test), max_universe: U0, variables: [Region(U0), Region(U0), Region(U0), Region(U0)] }, span: $DIR/receiver_ptr_mutability.rs:19:18: 19:31, inferred_ty: &&&&*mut Test
+| 3: user_ty: Canonical { value: Ty(&&&&*mut Test), max_universe: U0, variables: [Region(U0), Region(U0), Region(U0), Region(U0)] }, span: $DIR/receiver_ptr_mutability.rs:19:18: 19:31, inferred_ty: &&&&*mut Test
 |
 fn main() -> () {
     let mut _0: ();
diff --git a/tests/rustdoc-js/auxiliary/interner.rs b/tests/rustdoc-js/auxiliary/interner.rs
index e4e4ff6276d66..8af3b732ef7a0 100644
--- a/tests/rustdoc-js/auxiliary/interner.rs
+++ b/tests/rustdoc-js/auxiliary/interner.rs
@@ -18,7 +18,7 @@ pub trait Interner: Sized {
     type Binder<T: TypeVisitable<Self>>: BoundVars<Self> + TypeSuperVisitable<Self>;
     type BoundVars: IntoIterator<Item = Self::BoundVar>;
     type BoundVar;
-    type CanonicalVars: Copy + Debug + Hash + Eq + IntoIterator<Item = CanonicalVarInfo<Self>>;
+    type CanonicalVarKinds: Copy + Debug + Hash + Eq + IntoIterator<Item = CanonicalVarKind<Self>>;
     type Ty: Copy
         + DebugWithInfcx<Self>
         + Hash
@@ -77,7 +77,7 @@ pub trait Interner: Sized {
     type ClosureKind: Copy + Debug + Hash + Eq;
 
     // Required method
-    fn mk_canonical_var_infos(self, infos: &[CanonicalVarInfo<Self>]) -> Self::CanonicalVars;
+    fn mk_canonical_var_kinds(self, kinds: &[CanonicalVarKind<Self>]) -> Self::CanonicalVarKinds;
 }
 
 pub trait DebugWithInfcx<I: Interner>: Debug {
@@ -104,10 +104,6 @@ pub trait TypeSuperVisitable<I: Interner>: TypeVisitable<I> {
     fn super_visit_with<V: TypeVisitor<I>>(&self, visitor: &mut V) -> V::Result;
 }
 
-pub struct CanonicalVarInfo<I: Interner> {
-    pub kind: CanonicalVarKind<I>,
-}
-
 pub struct CanonicalVarKind<I>(std::marker::PhantomData<I>);
 
 pub struct TyKind<I>(std::marker::PhantomData<I>);
diff --git a/tests/rustdoc-js/looks-like-rustc-interner.js b/tests/rustdoc-js/looks-like-rustc-interner.js
index d6d2764c3aede..7d0511944546a 100644
--- a/tests/rustdoc-js/looks-like-rustc-interner.js
+++ b/tests/rustdoc-js/looks-like-rustc-interner.js
@@ -3,13 +3,13 @@
 
 const EXPECTED = [
     {
-        'query': 'canonicalvarinfo, intoiterator -> intoiterator',
+        'query': 'CanonicalVarKind, intoiterator -> intoiterator',
         'others': [],
     },
     {
-        'query': '[canonicalvarinfo], interner<tys=intoiterator> -> intoiterator',
+        'query': '[CanonicalVarKind], interner<tys=intoiterator> -> intoiterator',
         'others': [
-            { 'path': 'looks_like_rustc_interner::Interner', 'name': 'mk_canonical_var_infos' },
+            { 'path': 'looks_like_rustc_interner::Interner', 'name': 'mk_canonical_var_kinds' },
         ],
     },
 ];