⚡ Fallback callback

.gas-snapshot

@@ -1,17 +1,17 @@
 IETest:testBalanceInERC20() (gas: 62602)
 IETest:testBalanceInETH() (gas: 53716)
-IETest:testCommandSendERC0() (gas: 114380)
-IETest:testCommandSendETH() (gas: 80852)
-IETest:testCommandSendUSDC() (gas: 147088)
-IETest:testCommandSwapDAI() (gas: 101806)
-IETest:testCommandSwapUSDC() (gas: 156797)
-IETest:testDeploy() (gas: 2132114)
+IETest:testCommandSendERC0() (gas: 114314)
+IETest:testCommandSendETH() (gas: 80786)
+IETest:testCommandSendUSDC() (gas: 147022)
+IETest:testCommandSwapDAI() (gas: 101074)
+IETest:testCommandSwapUSDC() (gas: 156385)
+IETest:testDeploy() (gas: 2106248)
 IETest:testENSNameFromENSHelper() (gas: 29103)
-IETest:testENSNameOwnership() (gas: 109220)
+IETest:testENSNameOwnership() (gas: 109286)
 IETest:testIENameSetting() (gas: 8187)
-IETest:testPreviewCommandSendDecimals() (gas: 111568)
-IETest:testPreviewCommandSendUSDC() (gas: 77413)
+IETest:testPreviewCommandSendDecimals() (gas: 111612)
+IETest:testPreviewCommandSendUSDC() (gas: 77435)
 IETest:testPreviewSend() (gas: 54713)
-IETest:testPreviewSendCommand() (gas: 66562)
+IETest:testPreviewSendCommand() (gas: 66584)
 IETest:testSendETH() (gas: 70967)
 IETest:testTotalSupply() (gas: 14871)

src/IE.sol

@@ -294,29 +294,6 @@ contract IE {
         );
     }
 
-    /// @dev Callback for IUniswapV3PoolActions#swap. If ETH is source, WETH is forwarded.
-    function uniswapV3SwapCallback(int256 amount0Delta, int256 amount1Delta, bytes calldata data)
-        public
-        payable
-        virtual
-    {
-        bool isETH;
-        bool zeroForOne;
-        address tokenIn;
-        address payer;
-        assembly ("memory-safe") {
-            isETH := byte(0, calldataload(data.offset))
-            zeroForOne := byte(0, calldataload(add(data.offset, 1)))
-            tokenIn := shr(96, calldataload(add(data.offset, 2)))
-            payer := shr(96, calldataload(add(data.offset, 22)))
-        }
-        isETH
-            ? WETH.safeTransfer(msg.sender, uint256(zeroForOne ? amount0Delta : amount1Delta))
-            : tokenIn.safeTransferFrom(
-                payer, msg.sender, uint256(zeroForOne ? amount0Delta : amount1Delta)
-            );
-    }
-
     /// @dev Computes the create2 address for given token pair.
     function _computePoolAddress(address tokenA, address tokenB)
         internal
@@ -341,6 +318,31 @@ contract IE {
         );
     }
 
+    /// @dev Fallback `uniswapV3SwapCallback`.
+    /// If ETH is swapped, WETH is forwarded.
+    fallback() external {
+        int256 amount0Delta;
+        int256 amount1Delta;
+        bool isETH;
+        bool zeroForOne;
+        address tokenIn;
+        address payer;
+        assembly ("memory-safe") {
+            let pos := 132
+            amount0Delta := calldataload(4)
+            amount1Delta := calldataload(36)
+            isETH := byte(0, calldataload(pos))
+            zeroForOne := byte(0, calldataload(add(pos, 1)))
+            tokenIn := shr(96, calldataload(add(pos, 2)))
+            payer := shr(96, calldataload(add(pos, 22)))
+        }
+        isETH
+            ? WETH.safeTransfer(msg.sender, uint256(zeroForOne ? amount0Delta : amount1Delta))
+            : tokenIn.safeTransferFrom(
+                payer, msg.sender, uint256(zeroForOne ? amount0Delta : amount1Delta)
+            );
+    }
+
     /// ================== BALANCE & SUPPLY HELPERS ================== ///
 
     /// @dev Returns the balance of a named account in a named token.