Remove unused HybridBitSet methods from BitSetExt.

Author: nnethercote

compiler/rustc_mir_dataflow/src/framework/lattice.rs

@@ -40,7 +40,7 @@
 
 use std::iter;
 
-use rustc_index::bit_set::{BitSet, ChunkedBitSet, HybridBitSet};
+use rustc_index::bit_set::{BitSet, ChunkedBitSet};
 use rustc_index::{Idx, IndexVec};
 
 use crate::framework::BitSetExt;
@@ -198,14 +198,6 @@ impl<T: Idx> BitSetExt<T> for Dual<BitSet<T>> {
     fn contains(&self, elem: T) -> bool {
         self.0.contains(elem)
     }
-
-    fn union(&mut self, other: &HybridBitSet<T>) {
-        self.0.union(other);
-    }
-
-    fn subtract(&mut self, other: &HybridBitSet<T>) {
-        self.0.subtract(other);
-    }
 }
 
 impl<T: MeetSemiLattice> JoinSemiLattice for Dual<T> {
@@ -331,20 +323,6 @@ impl<T, S: BitSetExt<T>> BitSetExt<T> for MaybeReachable<S> {
     fn contains(&self, elem: T) -> bool {
         self.contains(elem)
     }
-
-    fn union(&mut self, other: &HybridBitSet<T>) {
-        match self {
-            MaybeReachable::Unreachable => {}
-            MaybeReachable::Reachable(set) => set.union(other),
-        }
-    }
-
-    fn subtract(&mut self, other: &HybridBitSet<T>) {
-        match self {
-            MaybeReachable::Unreachable => {}
-            MaybeReachable::Reachable(set) => set.subtract(other),
-        }
-    }
 }
 
 impl<V: Clone> Clone for MaybeReachable<V> {

compiler/rustc_mir_dataflow/src/framework/mod.rs

@@ -34,7 +34,7 @@
 use std::cmp::Ordering;
 
 use rustc_data_structures::work_queue::WorkQueue;
-use rustc_index::bit_set::{BitSet, ChunkedBitSet, HybridBitSet};
+use rustc_index::bit_set::{BitSet, ChunkedBitSet};
 use rustc_index::{Idx, IndexVec};
 use rustc_middle::bug;
 use rustc_middle::mir::{self, BasicBlock, CallReturnPlaces, Location, TerminatorEdges, traversal};
@@ -62,36 +62,18 @@ pub use self::visitor::{ResultsVisitor, visit_results};
 /// operations needed by all of them.
 pub trait BitSetExt<T> {
     fn contains(&self, elem: T) -> bool;
-    fn union(&mut self, other: &HybridBitSet<T>);
-    fn subtract(&mut self, other: &HybridBitSet<T>);
 }
 
 impl<T: Idx> BitSetExt<T> for BitSet<T> {
     fn contains(&self, elem: T) -> bool {
         self.contains(elem)
     }
-
-    fn union(&mut self, other: &HybridBitSet<T>) {
-        self.union(other);
-    }
-
-    fn subtract(&mut self, other: &HybridBitSet<T>) {
-        self.subtract(other);
-    }
 }
 
 impl<T: Idx> BitSetExt<T> for ChunkedBitSet<T> {
     fn contains(&self, elem: T) -> bool {
         self.contains(elem)
     }
-
-    fn union(&mut self, other: &HybridBitSet<T>) {
-        self.union(other);
-    }
-
-    fn subtract(&mut self, other: &HybridBitSet<T>) {
-        self.subtract(other);
-    }
 }
 
 /// A dataflow problem with an arbitrarily complex transfer function.