Merge pull request #7390 from ethereum/sloadTest

Load resolver involving staticcall.

test/libyul/yulOptimizerTests/loadResolver/staticcall.yul

@@ -0,0 +1,27 @@
+{
+    let a := 0
+    let b := 1
+    let c := 2
+    sstore(a, b)
+    mstore(900, 7)
+    let d := staticcall(10000, 10, 0, 200, 0, 200)
+    sstore(add(a, 1), mload(900))
+    // Main test objective: replace this sload.
+    mstore(0, sload(a))
+}
+// ====
+// step: loadResolver
+// EVMVersion: >=byzantium
+// ----
+// {
+//     let a := 0
+//     let b := 1
+//     sstore(a, b)
+//     let _1 := 7
+//     let _2 := 900
+//     mstore(_2, _1)
+//     let _3 := 200
+//     pop(staticcall(10000, 10, a, _3, a, _3))
+//     sstore(1, mload(_2))
+//     mstore(a, b)
+// }