diff --git a/src/llvm-project b/src/llvm-project
index 2b9078f4afae8..8404254254e2b 160000
--- a/src/llvm-project
+++ b/src/llvm-project
@@ -1 +1 @@
-Subproject commit 2b9078f4afae82f60c5ac0fdb4af42d269e2f2f3
+Subproject commit 8404254254e2b4c9a80e7403659f6391b08203df
diff --git a/src/test/codegen/merge-functions.rs b/src/test/codegen/merge-functions.rs
new file mode 100644
index 0000000000000..5eefc0f98f1fe
--- /dev/null
+++ b/src/test/codegen/merge-functions.rs
@@ -0,0 +1,14 @@
+// compile-flags: -O
+#![crate_type = "lib"]
+
+// CHECK: @func2 = {{.*}}alias{{.*}}@func1
+
+#[no_mangle]
+pub fn func1(c: char) -> bool {
+    c == 's' || c == 'm' || c == 'h' || c == 'd' || c == 'w'
+}
+
+#[no_mangle]
+pub fn func2(c: char) -> bool {
+    matches!(c, 's' | 'm' | 'h' | 'd' | 'w')
+}