1 files changed, 10 insertions, 0 deletions
diff --git a/compiler/rustc_data_structures/src/sync/parallel.rs b/compiler/rustc_data_structures/src/sync/parallel.rs
index 64db39cc4c6..ab65c7f3a6b 100644
--- a/compiler/rustc_data_structures/src/sync/parallel.rs
+++ b/compiler/rustc_data_structures/src/sync/parallel.rs
@@ -237,3 +237,13 @@ pub fn par_map<I: DynSend, T: IntoIterator<Item = I>, R: DynSend, C: FromIterato
         }
     })
 }
+
+pub fn broadcast<R: DynSend>(op: impl Fn(usize) -> R + DynSync) -> Vec<R> {
+    if mode::is_dyn_thread_safe() {
+        let op = FromDyn::from(op);
+        let results = rayon_core::broadcast(|context| op.derive(op(context.index())));
+        results.into_iter().map(|r| r.into_inner()).collect()
+    } else {
+        vec![op(0)]
+    }
+}