inline Address.functionDelegateCall and remove from Address library

contracts/mocks/AddressImpl.sol

@@ -32,11 +32,6 @@ contract AddressImpl {
         emit CallReturnValue(abi.decode(returnData, (string)));
     }
 
-    function functionDelegateCall(address target, bytes calldata data) external {
-        bytes memory returnData = Address.functionDelegateCall(target, data);
-        emit CallReturnValue(abi.decode(returnData, (string)));
-    }
-
     // sendValue's tests require the contract to hold Ether
     receive () external payable { }
 }

contracts/proxy/ERC1967/ERC1967Upgrade.sol

@@ -50,7 +50,7 @@ abstract contract ERC1967Upgrade is ERC1967Storage {
         _setImplementation(newImplementation);
         emit Upgraded(newImplementation);
         if (data.length > 0 || forceCall) {
-            Address.functionDelegateCall(newImplementation, data);
+            _functionDelegateCall(newImplementation, data);
         }
     }
 
@@ -65,7 +65,7 @@ abstract contract ERC1967Upgrade is ERC1967Storage {
         // Initial upgrade and setup call
         _setImplementation(newImplementation);
         if (data.length > 0 || forceCall) {
-            Address.functionDelegateCall(newImplementation, data);
+            _functionDelegateCall(newImplementation, data);
         }
 
         // Perform rollback test if not already in progress
@@ -73,7 +73,7 @@ abstract contract ERC1967Upgrade is ERC1967Storage {
         if (!rollbackTesting.value) {
             // Trigger rollback using upgradeTo from the new implementation
             rollbackTesting.value = true;
-            Address.functionDelegateCall(
+            _functionDelegateCall(
                 newImplementation,
                 abi.encodeWithSignature(
                     "upgradeTo(address)",
@@ -99,7 +99,7 @@ abstract contract ERC1967Upgrade is ERC1967Storage {
         _setBeacon(newBeacon);
         emit BeaconUpgraded(newBeacon);
         if (data.length > 0 || forceCall) {
-            Address.functionDelegateCall(IBeacon(newBeacon).implementation(), data);
+            _functionDelegateCall(IBeacon(newBeacon).implementation(), data);
         }
     }
 
@@ -112,4 +112,37 @@ abstract contract ERC1967Upgrade is ERC1967Storage {
         emit AdminChanged(_getAdmin(), newAdmin);
         _setAdmin(newAdmin);
     }
+
+    /**
+     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
+     * but performing a delegate call.
+     *
+     * _Available since v3.4._
+     */
+    function _functionDelegateCall(address target, bytes memory data) private returns (bytes memory) {
+        require(Address.isContract(target), "Address: delegate call to non-contract");
+
+        // solhint-disable-next-line avoid-low-level-calls
+        (bool success, bytes memory returndata) = target.delegatecall(data);
+        return _verifyCallResult(success, returndata, "Address: low-level delegate call failed");
+    }
+
+    function _verifyCallResult(bool success, bytes memory returndata, string memory errorMessage) private pure returns(bytes memory) {
+        if (success) {
+            return returndata;
+        } else {
+            // Look for revert reason and bubble it up if present
+            if (returndata.length > 0) {
+                // The easiest way to bubble the revert reason is using memory via assembly
+
+                // solhint-disable-next-line no-inline-assembly
+                assembly {
+                    let returndata_size := mload(returndata)
+                    revert(add(32, returndata), returndata_size)
+                }
+            } else {
+                revert(errorMessage);
+            }
+        }
+    }
 }

contracts/utils/Address.sol

@@ -144,30 +144,6 @@ library Address {
         return _verifyCallResult(success, returndata, errorMessage);
     }
 
-    /**
-     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
-     * but performing a delegate call.
-     *
-     * _Available since v3.4._
-     */
-    function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
-        return functionDelegateCall(target, data, "Address: low-level delegate call failed");
-    }
-
-    /**
-     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
-     * but performing a delegate call.
-     *
-     * _Available since v3.4._
-     */
-    function functionDelegateCall(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {
-        require(isContract(target), "Address: delegate call to non-contract");
-
-        // solhint-disable-next-line avoid-low-level-calls
-        (bool success, bytes memory returndata) = target.delegatecall(data);
-        return _verifyCallResult(success, returndata, errorMessage);
-    }
-
     function _verifyCallResult(bool success, bytes memory returndata, string memory errorMessage) private pure returns(bytes memory) {
         if (success) {
             return returndata;

contracts/utils/Multicall.sol

@@ -16,8 +16,41 @@ abstract contract Multicall {
     function multicall(bytes[] calldata data) external returns (bytes[] memory results) {
         results = new bytes[](data.length);
         for (uint i = 0; i < data.length; i++) {
-            results[i] = Address.functionDelegateCall(address(this), data[i]);
+            results[i] = _functionDelegateCall(address(this), data[i]);
         }
         return results;
     }
+
+    /**
+     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
+     * but performing a delegate call.
+     *
+     * _Available since v3.4._
+     */
+    function _functionDelegateCall(address target, bytes memory data) private returns (bytes memory) {
+        require(Address.isContract(target), "Address: delegate call to non-contract");
+
+        // solhint-disable-next-line avoid-low-level-calls
+        (bool success, bytes memory returndata) = target.delegatecall(data);
+        return _verifyCallResult(success, returndata, "Address: low-level delegate call failed");
+    }
+
+    function _verifyCallResult(bool success, bytes memory returndata, string memory errorMessage) private pure returns(bytes memory) {
+        if (success) {
+            return returndata;
+        } else {
+            // Look for revert reason and bubble it up if present
+            if (returndata.length > 0) {
+                // The easiest way to bubble the revert reason is using memory via assembly
+
+                // solhint-disable-next-line no-inline-assembly
+                assembly {
+                    let returndata_size := mload(returndata)
+                    revert(add(32, returndata), returndata_size)
+                }
+            } else {
+                revert(errorMessage);
+            }
+        }
+    }
 }

scripts/upgradeable/patch/01-inline-address-functiondelegatecall.patch

-diff --git a/contracts/mocks/AddressImplUpgradeable.sol b/contracts/mocks/AddressImplUpgradeable.sol
-index 4e92f588..4cbcabb8 100644
---- a/contracts/mocks/AddressImplUpgradeable.sol
-+++ b/contracts/mocks/AddressImplUpgradeable.sol
-@@ -39,11 +39,6 @@ contract AddressImplUpgradeable is Initializable {
-         emit CallReturnValue(abi.decode(returnData, (string)));
-     }
- 
--    function functionDelegateCall(address target, bytes calldata data) external {
--        bytes memory returnData = AddressUpgradeable.functionDelegateCall(target, data);
--        emit CallReturnValue(abi.decode(returnData, (string)));
--    }
--
-     // sendValue's tests require the contract to hold Ether
-     receive () external payable { }
-     uint256[49] private __gap;
-diff --git a/contracts/utils/AddressUpgradeable.sol b/contracts/utils/AddressUpgradeable.sol
-index 89241895..99c1ce78 100644
---- a/contracts/utils/AddressUpgradeable.sol
-+++ b/contracts/utils/AddressUpgradeable.sol
-@@ -144,30 +144,6 @@ library AddressUpgradeable {
-         return _verifyCallResult(success, returndata, errorMessage);
-     }
- 
--    /**
--     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
--     * but performing a delegate call.
--     *
--     * _Available since v3.4._
--     */
--    function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
--        return functionDelegateCall(target, data, "Address: low-level delegate call failed");
--    }
--
--    /**
--     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
--     * but performing a delegate call.
--     *
--     * _Available since v3.4._
--     */
--    function functionDelegateCall(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {
--        require(isContract(target), "Address: delegate call to non-contract");
--
--        // solhint-disable-next-line avoid-low-level-calls
--        (bool success, bytes memory returndata) = target.delegatecall(data);
--        return _verifyCallResult(success, returndata, errorMessage);
--    }
--
-     function _verifyCallResult(bool success, bytes memory returndata, string memory errorMessage) private pure returns(bytes memory) {
-         if (success) {
-             return returndata;
-diff --git a/contracts/utils/MulticallUpgradeable.sol b/contracts/utils/MulticallUpgradeable.sol
-index 62d5047c..a535dfc5 100644
---- a/contracts/utils/MulticallUpgradeable.sol
-+++ b/contracts/utils/MulticallUpgradeable.sol
-@@ -21,9 +21,37 @@ abstract contract MulticallUpgradeable is Initializable {
-     function multicall(bytes[] calldata data) external returns (bytes[] memory results) {
-         results = new bytes[](data.length);
-         for (uint i = 0; i < data.length; i++) {
--            results[i] = AddressUpgradeable.functionDelegateCall(address(this), data[i]);
-+            results[i] = _functionDelegateCall(address(this), data[i]);
-         }
-         return results;
-     }
-+
-+    function _functionDelegateCall(address target, bytes memory data) private returns (bytes memory) {
-+        require(AddressUpgradeable.isContract(target), "Address: delegate call to non-contract");
-+
-+        // solhint-disable-next-line avoid-low-level-calls
-+        (bool success, bytes memory returndata) = target.delegatecall(data);
-+        return _verifyCallResult(success, returndata, "Address: low-level delegate call failed");
-+    }
-+
-+    function _verifyCallResult(bool success, bytes memory returndata, string memory errorMessage) private pure returns(bytes memory) {
-+        if (success) {
-+            return returndata;
-+        } else {
-+            // Look for revert reason and bubble it up if present
-+            if (returndata.length > 0) {
-+                // The easiest way to bubble the revert reason is using memory via assembly
-+
-+                // solhint-disable-next-line no-inline-assembly
-+                assembly {
-+                    let returndata_size := mload(returndata)
-+                    revert(add(32, returndata), returndata_size)
-+                }
-+            } else {
-+                revert(errorMessage);
-+            }
-+        }
-+    }
-+
-     uint256[50] private __gap;
- }