1 files changed, 27 insertions, 7 deletions
diff --git a/compiler/rustc_mir_dataflow/src/framework/fmt.rs b/compiler/rustc_mir_dataflow/src/framework/fmt.rs
index dc176ba2d03..faf2c411dde 100644
--- a/compiler/rustc_mir_dataflow/src/framework/fmt.rs
+++ b/compiler/rustc_mir_dataflow/src/framework/fmt.rs
@@ -4,7 +4,7 @@
 use std::fmt;
 
 use rustc_index::Idx;
-use rustc_index::bit_set::{BitSet, ChunkedBitSet};
+use rustc_index::bit_set::{BitSet, ChunkedBitSet, MixedBitSet};
 
 use super::lattice::MaybeReachable;
 
@@ -85,8 +85,8 @@ where
         let size = self.domain_size();
         assert_eq!(size, old.domain_size());
 
-        let mut set_in_self = ChunkedBitSet::new_empty(size);
-        let mut cleared_in_self = ChunkedBitSet::new_empty(size);
+        let mut set_in_self = MixedBitSet::new_empty(size);
+        let mut cleared_in_self = MixedBitSet::new_empty(size);
 
         for i in (0..size).map(T::new) {
             match (self.contains(i), old.contains(i)) {
@@ -112,8 +112,8 @@ where
         let size = self.domain_size();
         assert_eq!(size, old.domain_size());
 
-        let mut set_in_self = ChunkedBitSet::new_empty(size);
-        let mut cleared_in_self = ChunkedBitSet::new_empty(size);
+        let mut set_in_self = MixedBitSet::new_empty(size);
+        let mut cleared_in_self = MixedBitSet::new_empty(size);
 
         for i in (0..size).map(T::new) {
             match (self.contains(i), old.contains(i)) {
@@ -127,6 +127,26 @@ where
     }
 }
 
+impl<T, C> DebugWithContext<C> for MixedBitSet<T>
+where
+    T: Idx + DebugWithContext<C>,
+{
+    fn fmt_with(&self, ctxt: &C, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        match self {
+            MixedBitSet::Small(set) => set.fmt_with(ctxt, f),
+            MixedBitSet::Large(set) => set.fmt_with(ctxt, f),
+        }
+    }
+
+    fn fmt_diff_with(&self, old: &Self, ctxt: &C, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        match (self, old) {
+            (MixedBitSet::Small(set), MixedBitSet::Small(old)) => set.fmt_diff_with(old, ctxt, f),
+            (MixedBitSet::Large(set), MixedBitSet::Large(old)) => set.fmt_diff_with(old, ctxt, f),
+            _ => panic!("MixedBitSet size mismatch"),
+        }
+    }
+}
+
 impl<S, C> DebugWithContext<C> for MaybeReachable<S>
 where
     S: DebugWithContext<C>,
@@ -159,8 +179,8 @@ where
 }
 
 fn fmt_diff<T, C>(
-    inserted: &ChunkedBitSet<T>,
-    removed: &ChunkedBitSet<T>,
+    inserted: &MixedBitSet<T>,
+    removed: &MixedBitSet<T>,
     ctxt: &C,
     f: &mut fmt::Formatter<'_>,
 ) -> fmt::Result