Add a test

Author: saethlin

tests/mir-opt/reference_prop_do_not_reuse_move.rs

@@ -0,0 +1,44 @@
+//@ test-mir-pass: ReferencePropagation
+
+#![feature(custom_mir, core_intrinsics)]
+#![allow(internal_features)]
+#![crate_type = "lib"]
+
+use std::intrinsics::mir::*;
+
+#[inline(never)]
+fn opaque(_: impl Sized, _: impl Sized) {}
+
+#[custom_mir(dialect = "runtime")]
+pub fn fn0() {
+    // CHECK-LABEL: fn0
+    // CHECK: _9 = opaque::<&u8, &u64>(copy (_2.1: &u8), copy _6) -> [return: bb1, unwind unreachable];
+    mir! {
+        let _1: (u8, u8);
+        let _2: (u64, &u8);
+        let _3: (u8, &&u64);
+        let _4: u64;
+        let _5: &u64;
+        let _6: &u64;
+        let _7: &u64;
+        let _8: u64;
+        let n: ();
+        {
+            _3.0 = 0;
+            _1 = (0, _3.0);
+            _4 = 0;
+            _2.1 = &_1.0;
+            _8 = 0;
+            _5 = &_8;
+            _5 = &_4;
+            _6 = _5;
+            _7 = _6;
+            _3.1 = &_6;
+            Call(n = opaque(_2.1, Move(_6)), ReturnTo(bb1), UnwindUnreachable())
+        }
+        bb1 = {
+            _2.0 = *_7;
+            Return()
+        }
+    }
+}