rename `BitSet` to `DenseBitSet`

This should make it clearer that this bitset is dense, with the
advantages and disadvantages that it entails.

1 files changed, 2 insertions, 2 deletions

diff --git a/compiler/rustc_mir_transform/src/nrvo.rs b/compiler/rustc_mir_transform/src/nrvo.rs
index cd026ed6806..35872de3852 100644
--- a/compiler/rustc_mir_transform/src/nrvo.rs
+++ b/compiler/rustc_mir_transform/src/nrvo.rs
@@ -1,7 +1,7 @@
 //! See the docs for [`RenameReturnPlace`].
 
 use rustc_hir::Mutability;
-use rustc_index::bit_set::BitSet;
+use rustc_index::bit_set::DenseBitSet;
 use rustc_middle::bug;
 use rustc_middle::mir::visit::{MutVisitor, NonUseContext, PlaceContext, Visitor};
 use rustc_middle::mir::{self, BasicBlock, Local, Location};
@@ -116,7 +116,7 @@ fn local_eligible_for_nrvo(body: &mir::Body<'_>) -> Option<Local> {
 
 fn find_local_assigned_to_return_place(start: BasicBlock, body: &mir::Body<'_>) -> Option<Local> {
     let mut block = start;
-    let mut seen = BitSet::new_empty(body.basic_blocks.len());
+    let mut seen = DenseBitSet::new_empty(body.basic_blocks.len());
 
     // Iterate as long as `block` has exactly one predecessor that we have not yet visited.
     while seen.insert(block) {