3 files changed, 8 insertions, 35 deletions
diff --git a/compiler/rustc_middle/src/ty/context.rs b/compiler/rustc_middle/src/ty/context.rs
index 6e53b5bb520..318a18715e4 100644
--- a/compiler/rustc_middle/src/ty/context.rs
+++ b/compiler/rustc_middle/src/ty/context.rs
@@ -1488,13 +1488,14 @@ impl<'tcx> TyCtxt<'tcx> {
     }
 
     /// Returns the `DefId` and the `BoundRegionKind` corresponding to the given region.
-    pub fn is_suitable_region(self, mut region: Region<'tcx>) -> Option<FreeRegionInfo> {
+    pub fn is_suitable_region(
+        self,
+        generic_param_scope: LocalDefId,
+        mut region: Region<'tcx>,
+    ) -> Option<FreeRegionInfo> {
         let (suitable_region_binding_scope, bound_region) = loop {
-            let def_id = match region.kind() {
-                ty::ReLateParam(fr) => fr.bound_region.get_id()?.as_local()?,
-                ty::ReEarlyParam(ebr) => ebr.def_id.as_local()?,
-                _ => return None, // not a free region
-            };
+            let def_id =
+                region.opt_param_def_id(self, generic_param_scope.to_def_id())?.as_local()?;
             let scope = self.local_parent(def_id);
             if self.def_kind(scope) == DefKind::OpaqueTy {
                 // Lifetime params of opaque types are synthetic and thus irrelevant to
@@ -2633,7 +2634,6 @@ impl<'tcx> TyCtxt<'tcx> {
                     return ty::Region::new_early_param(
                         self,
                         ty::EarlyParamRegion {
-                            def_id: ebv,
                             index: generics
                                 .param_def_id_to_index(self, ebv)
                                 .expect("early-bound var should be present in fn generics"),
diff --git a/compiler/rustc_middle/src/ty/generics.rs b/compiler/rustc_middle/src/ty/generics.rs
index 870e4865aea..8fdff40024b 100644
--- a/compiler/rustc_middle/src/ty/generics.rs
+++ b/compiler/rustc_middle/src/ty/generics.rs
@@ -66,7 +66,7 @@ pub struct GenericParamDef {
 impl GenericParamDef {
     pub fn to_early_bound_region_data(&self) -> ty::EarlyParamRegion {
         if let GenericParamDefKind::Lifetime = self.kind {
-            ty::EarlyParamRegion { def_id: self.def_id, index: self.index, name: self.name }
+            ty::EarlyParamRegion { index: self.index, name: self.name }
         } else {
             bug!("cannot convert a non-lifetime parameter def to an early bound region")
         }
diff --git a/compiler/rustc_middle/src/ty/region.rs b/compiler/rustc_middle/src/ty/region.rs
index 0e07ef31c26..0807cbf91d1 100644
--- a/compiler/rustc_middle/src/ty/region.rs
+++ b/compiler/rustc_middle/src/ty/region.rs
@@ -265,33 +265,6 @@ impl<'tcx> Region<'tcx> {
         flags
     }
 
-    /// Given an early-bound or free region, returns the `DefId` where it was bound.
-    /// For example, consider the regions in this snippet of code:
-    ///
-    /// ```ignore (illustrative)
-    /// impl<'a> Foo {
-    /// //   ^^ -- early bound, declared on an impl
-    ///
-    ///     fn bar<'b, 'c>(x: &self, y: &'b u32, z: &'c u64) where 'static: 'c
-    /// //         ^^  ^^     ^ anonymous, late-bound
-    /// //         |   early-bound, appears in where-clauses
-    /// //         late-bound, appears only in fn args
-    ///     {..}
-    /// }
-    /// ```
-    ///
-    /// Here, `free_region_binding_scope('a)` would return the `DefId`
-    /// of the impl, and for all the other highlighted regions, it
-    /// would return the `DefId` of the function. In other cases (not shown), this
-    /// function might return the `DefId` of a closure.
-    pub fn free_region_binding_scope(self, tcx: TyCtxt<'_>) -> DefId {
-        match *self {
-            ty::ReEarlyParam(br) => tcx.parent(br.def_id),
-            ty::ReLateParam(fr) => fr.scope,
-            _ => bug!("free_region_binding_scope invoked on inappropriate region: {:?}", self),
-        }
-    }
-
     /// True for free regions other than `'static`.
     pub fn is_param(self) -> bool {
         matches!(*self, ty::ReEarlyParam(_) | ty::ReLateParam(_))