Test case that shows a CSE bug related to scopes.

1 files changed, 25 insertions, 0 deletions

diff --git a/test/libyul/yulOptimizerTests/commonSubexpressionEliminator/scopes.yul b/test/libyul/yulOptimizerTests/commonSubexpressionEliminator/scopes.yul
new file mode 100644
index 00000000..35270d87
--- /dev/null
+++ b/test/libyul/yulOptimizerTests/commonSubexpressionEliminator/scopes.yul
@@ -0,0 +1,25 @@
+{
+    let a := 10
+    let x := 20
+    {
+        let b := calldataload(0)
+        let d := calldataload(1)
+        x := d
+    }
+    // We had a bug where "calldataload(0)" was incorrectly replaced by "b"
+    mstore(0, calldataload(0))
+    mstore(0, x)
+}
+// ----
+// commonSubexpressionEliminator
+// {
+//     let a := 10
+//     let x := 20
+//     {
+//         let b := calldataload(0)
+//         let d := calldataload(1)
+//         x := d
+//     }
+//     mstore(0, b)
+//     mstore(0, x)
+// }