1 files changed, 45 insertions, 0 deletions
diff --git a/compiler/rustc_data_structures/src/graph/dominators/tests.rs b/compiler/rustc_data_structures/src/graph/dominators/tests.rs
new file mode 100644
index 000000000..ff31d8f7f
--- /dev/null
+++ b/compiler/rustc_data_structures/src/graph/dominators/tests.rs
@@ -0,0 +1,45 @@
+use super::*;
+
+use super::super::tests::TestGraph;
+
+#[test]
+fn diamond() {
+    let graph = TestGraph::new(0, &[(0, 1), (0, 2), (1, 3), (2, 3)]);
+
+    let dominators = dominators(&graph);
+    let immediate_dominators = &dominators.immediate_dominators;
+    assert_eq!(immediate_dominators[0], Some(0));
+    assert_eq!(immediate_dominators[1], Some(0));
+    assert_eq!(immediate_dominators[2], Some(0));
+    assert_eq!(immediate_dominators[3], Some(0));
+}
+
+#[test]
+fn paper() {
+    // example from the paper:
+    let graph = TestGraph::new(
+        6,
+        &[(6, 5), (6, 4), (5, 1), (4, 2), (4, 3), (1, 2), (2, 3), (3, 2), (2, 1)],
+    );
+
+    let dominators = dominators(&graph);
+    let immediate_dominators = &dominators.immediate_dominators;
+    assert_eq!(immediate_dominators[0], None); // <-- note that 0 is not in graph
+    assert_eq!(immediate_dominators[1], Some(6));
+    assert_eq!(immediate_dominators[2], Some(6));
+    assert_eq!(immediate_dominators[3], Some(6));
+    assert_eq!(immediate_dominators[4], Some(6));
+    assert_eq!(immediate_dominators[5], Some(6));
+    assert_eq!(immediate_dominators[6], Some(6));
+}
+
+#[test]
+fn paper_slt() {
+    // example from the paper:
+    let graph = TestGraph::new(
+        1,
+        &[(1, 2), (1, 3), (2, 3), (2, 7), (3, 4), (3, 6), (4, 5), (5, 4), (6, 7), (7, 8), (8, 5)],
+    );
+
+    dominators(&graph);
+}