Add tests

Author: r0qs

Diff for: test/libsolidity/semanticTests/storage/delete_overflow_bug_collision.sol

@@ -0,0 +1,29 @@
+contract C {
+    uint256 y = 42;
+
+    function getArray() internal returns (uint256[10][1] storage x) {
+        assembly {
+            x.slot := sub(0, 1)
+        }
+    }
+
+    function f() public returns (uint256[10] memory) {
+        uint256[10][1] storage x = getArray();
+        for (uint i = 0; i < 10; i++)
+            x[0][i] = i;
+        delete x[0];
+        return x[0];
+    }
+
+    function g() public view returns (uint256) {
+        return y;
+    }
+}
+
+// ----
+// g() -> 42
+// f() -> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
+// gas irOptimized: 168243
+// gas legacy: 170463
+// gas legacyOptimized: 168219
+// g() -> 0

Diff for: test/libsolidity/semanticTests/storage/delete_overflow_bug_large_mapping_storage_boundary.sol

@@ -0,0 +1,24 @@
+contract C {
+    mapping(string => uint256[256][2**240]) m;
+
+    function f() public returns (uint256[256] memory) {
+        uint256[256][2**240] storage a = m["v 2.2.3"]; // storage slot at: 115727151504557284028719796883655996022159813646012550228975965253679287557055
+        uint256 slot;
+         assembly {
+             slot := a.slot
+         }
+
+        // Pick the largest k such that `slot + 256 * k` <= `2**256 - 1`
+        uint240 k = uint240((type(uint256).max - slot) / 256);
+        require(k <= type(uint240).max);
+
+        a[k] = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10];
+        delete a[k];
+        return a[k];
+    }
+}
+
+// ----
+// f() -> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
+// gas irOptimized: 723216
+// gas legacyOptimized: 717881

Diff for: test/libsolidity/semanticTests/storage/delete_overflow_bug_partial_assignment.sol

@@ -0,0 +1,19 @@
+contract C {
+    function getArray() internal returns (uint256[10][1] storage x) {
+        assembly {
+            x.slot := sub(0, 1)
+        }
+    }
+    function f() public returns (uint256[10] memory) {
+        uint256[10][1] storage x = getArray();
+        for (uint i = 0; i < 10; i++)
+            x[0][i] = i;
+        x[0] = [11, 12, 13];
+        return x[0];
+    }
+}
+// ----
+// f() -> 11, 12, 13, 0, 0, 0, 0, 0, 0, 0
+// gas irOptimized: 198025
+// gas legacy: 200268
+// gas legacyOptimized: 198039

Diff for: test/libsolidity/semanticTests/storage/delete_overflow_bug_storage_layout.sol

@@ -0,0 +1,22 @@
+contract C layout at 2**256 - 2 {
+    uint256 a;
+
+    function getArray() internal returns (uint256[10][1] storage x) {
+        assembly {
+            x.slot := a.slot
+        }
+    }
+
+    function f() public returns (uint256[10] memory) {
+        uint256[10][1] storage x = getArray();
+        for (uint i = 0; i < 10; i++)
+            x[0][i] = i;
+        delete x[0];
+        return x[0];
+    }
+}
+// ----
+// f() -> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
+// gas irOptimized: 181930
+// gas legacy: 184143
+// gas legacyOptimized: 181900