Use `&IndexSlice` instead of `&IndexVec` where possible

All the same reasons as for `[T]`: more general, less pointer chasing, and `&mut IndexSlice` emphasizes that it doesn't change *length*.

3 files changed, 12 insertions, 12 deletions

diff --git a/compiler/rustc_data_structures/src/graph/dominators/mod.rs b/compiler/rustc_data_structures/src/graph/dominators/mod.rs
index 0a21a4249c8..0df9dc112ee 100644
--- a/compiler/rustc_data_structures/src/graph/dominators/mod.rs
+++ b/compiler/rustc_data_structures/src/graph/dominators/mod.rs
@@ -10,7 +10,7 @@
 //! <https://www.cs.princeton.edu/courses/archive/spr03/cs423/download/dominators.pdf>
 
 use super::ControlFlowGraph;
-use rustc_index::vec::{Idx, IndexVec};
+use rustc_index::vec::{Idx, IndexSlice, IndexVec};
 use std::cmp::Ordering;
 
 #[cfg(test)]
@@ -256,10 +256,10 @@ pub fn dominators<G: ControlFlowGraph>(graph: G) -> Dominators<G::Node> {
 /// where `+>` is a proper ancestor and `*>` is just an ancestor.
 #[inline]
 fn eval(
-    ancestor: &mut IndexVec<PreorderIndex, PreorderIndex>,
+    ancestor: &mut IndexSlice<PreorderIndex, PreorderIndex>,
     lastlinked: Option<PreorderIndex>,
-    semi: &IndexVec<PreorderIndex, PreorderIndex>,
-    label: &mut IndexVec<PreorderIndex, PreorderIndex>,
+    semi: &IndexSlice<PreorderIndex, PreorderIndex>,
+    label: &mut IndexSlice<PreorderIndex, PreorderIndex>,
     node: PreorderIndex,
 ) -> PreorderIndex {
     if is_processed(node, lastlinked) {
@@ -277,10 +277,10 @@ fn is_processed(v: PreorderIndex, lastlinked: Option<PreorderIndex>) -> bool {
 
 #[inline]
 fn compress(
-    ancestor: &mut IndexVec<PreorderIndex, PreorderIndex>,
+    ancestor: &mut IndexSlice<PreorderIndex, PreorderIndex>,
     lastlinked: Option<PreorderIndex>,
-    semi: &IndexVec<PreorderIndex, PreorderIndex>,
-    label: &mut IndexVec<PreorderIndex, PreorderIndex>,
+    semi: &IndexSlice<PreorderIndex, PreorderIndex>,
+    label: &mut IndexSlice<PreorderIndex, PreorderIndex>,
     v: PreorderIndex,
 ) {
     assert!(is_processed(v, lastlinked));
diff --git a/compiler/rustc_data_structures/src/graph/iterate/mod.rs b/compiler/rustc_data_structures/src/graph/iterate/mod.rs
index 8a9af300c06..01a83b40a75 100644
--- a/compiler/rustc_data_structures/src/graph/iterate/mod.rs
+++ b/compiler/rustc_data_structures/src/graph/iterate/mod.rs
@@ -1,6 +1,6 @@
 use super::{DirectedGraph, WithNumNodes, WithStartNode, WithSuccessors};
 use rustc_index::bit_set::BitSet;
-use rustc_index::vec::IndexVec;
+use rustc_index::vec::{IndexSlice, IndexVec};
 use std::ops::ControlFlow;
 
 #[cfg(test)]
@@ -31,7 +31,7 @@ fn post_order_walk<G: DirectedGraph + WithSuccessors + WithNumNodes>(
     graph: &G,
     node: G::Node,
     result: &mut Vec<G::Node>,
-    visited: &mut IndexVec<G::Node, bool>,
+    visited: &mut IndexSlice<G::Node, bool>,
 ) {
     struct PostOrderFrame<Node, Iter> {
         node: Node,
diff --git a/compiler/rustc_data_structures/src/graph/scc/mod.rs b/compiler/rustc_data_structures/src/graph/scc/mod.rs
index c4b11951ab7..28c357e54dd 100644
--- a/compiler/rustc_data_structures/src/graph/scc/mod.rs
+++ b/compiler/rustc_data_structures/src/graph/scc/mod.rs
@@ -8,7 +8,7 @@
 use crate::fx::FxHashSet;
 use crate::graph::vec_graph::VecGraph;
 use crate::graph::{DirectedGraph, GraphSuccessors, WithNumEdges, WithNumNodes, WithSuccessors};
-use rustc_index::vec::{Idx, IndexVec};
+use rustc_index::vec::{Idx, IndexSlice, IndexVec};
 use std::ops::Range;
 
 #[cfg(test)]
@@ -43,7 +43,7 @@ impl<N: Idx, S: Idx + Ord> Sccs<N, S> {
         SccsConstruction::construct(graph)
     }
 
-    pub fn scc_indices(&self) -> &IndexVec<N, S> {
+    pub fn scc_indices(&self) -> &IndexSlice<N, S> {
         &self.scc_indices
     }
 
@@ -123,7 +123,7 @@ impl<S: Idx> SccData<S> {
         self.ranges.len()
     }
 
-    pub fn ranges(&self) -> &IndexVec<S, Range<usize>> {
+    pub fn ranges(&self) -> &IndexSlice<S, Range<usize>> {
         &self.ranges
     }