Merge and update snapshots

.forge-snapshots/addLiquidity with empty hook.snap

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-264533
+264375

.forge-snapshots/addLiquidity with native token.snap

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-139393
+139216

.forge-snapshots/addLiquidity.snap

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-144710
+144552

.forge-snapshots/donate gas with 1 token.snap

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-101128
+101147

.forge-snapshots/donate gas with 2 tokens.snap

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-132115
+132153

.forge-snapshots/poolManager bytecode size.snap

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-22511
+22366

.forge-snapshots/removeLiquidity with empty hook.snap

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-55193
+54720

.forge-snapshots/removeLiquidity with native token.snap

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-147379
+146903

.forge-snapshots/removeLiquidity.snap

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-148843
+148370

.forge-snapshots/simple swap.snap

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-146456
+146475

.forge-snapshots/swap against liquidity.snap

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-60115
+60134

.forge-snapshots/swap burn 6909 for input.snap

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-80276
+80275

.forge-snapshots/swap mint native output as 6909.snap

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-138624
+138642

.forge-snapshots/swap mint output as 6909.snap

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-155271
+155290

.forge-snapshots/swap skips hook call if hook is caller.snap

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-155683
+155727

.forge-snapshots/swap with dynamic fee.snap

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-89346
+89365

.forge-snapshots/swap with hooks.snap

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-60093
+60112

.forge-snapshots/update dynamic fee in before swap.snap

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-139972
+139991

src/Extsload.sol

@@ -0,0 +1,28 @@
+// SPDX-License-Identifier: MIT
+pragma solidity >=0.6.0;
+
+import {IExtsload} from "./interfaces/IExtsload.sol";
+
+/// @notice Enables public storage access for efficient state retrieval by external contracts.
+/// https://eips.ethereum.org/EIPS/eip-2330#rationale
+abstract contract Extsload is IExtsload {
+    function extsload(bytes32 slot) external view returns (bytes32 value) {
+        /// @solidity memory-safe-assembly
+        assembly {
+            value := sload(slot)
+        }
+    }
+
+    function extsload(bytes32 startSlot, uint256 nSlots) external view returns (bytes memory) {
+        bytes memory value = new bytes(32 * nSlots);
+
+        /// @solidity memory-safe-assembly
+        assembly {
+            for { let i := 0 } lt(i, nSlots) { i := add(i, 1) } {
+                mstore(add(value, mul(add(i, 1), 32)), sload(add(startSlot, i)))
+            }
+        }
+
+        return value;
+    }
+}

src/PoolManager.sol

@@ -21,9 +21,11 @@ import {Lock} from "./libraries/Lock.sol";
 import {CurrencyDelta} from "./libraries/CurrencyDelta.sol";
 import {NonZeroDeltaCount} from "./libraries/NonZeroDeltaCount.sol";
 import {PoolGetters} from "./libraries/PoolGetters.sol";
+import {Extsload} from "./Extsload.sol";
 
 /// @notice Holds the state for all pools
-contract PoolManager is IPoolManager, ProtocolFees, NoDelegateCall, ERC6909Claims {
+
+contract PoolManager is IPoolManager, ProtocolFees, NoDelegateCall, ERC6909Claims, Extsload {
     using PoolIdLibrary for PoolKey;
     using SafeCast for *;
     using Pool for *;
@@ -176,13 +178,13 @@ contract PoolManager is IPoolManager, ProtocolFees, NoDelegateCall, ERC6909Claim
         PoolKey memory key,
         IPoolManager.ModifyLiquidityParams memory params,
         bytes calldata hookData
-    ) external override onlyWhenUnlocked returns (BalanceDelta delta) {
+    ) external override onlyWhenUnlocked returns (BalanceDelta delta, BalanceDelta feeDelta) {
         PoolId id = key.toId();
         _checkPoolInitialized(id);
 
         key.hooks.beforeModifyLiquidity(key, params, hookData);
 
-        delta = pools[id].modifyLiquidity(
+        (delta, feeDelta) = pools[id].modifyLiquidity(
             Pool.ModifyLiquidityParams({
                 owner: msg.sender,
                 tickLower: params.tickLower,
@@ -192,7 +194,7 @@ contract PoolManager is IPoolManager, ProtocolFees, NoDelegateCall, ERC6909Claim
             })
         );
 
-        _accountPoolBalanceDelta(key, delta);
+        _accountPoolBalanceDelta(key, delta + feeDelta);
 
         emit ModifyLiquidity(id, msg.sender, params.tickLower, params.tickUpper, params.liquidityDelta);
 
@@ -269,6 +271,7 @@ contract PoolManager is IPoolManager, ProtocolFees, NoDelegateCall, ERC6909Claim
         if (currency.isNative()) {
             paid = msg.value;
         } else {
+            if (msg.value > 0) revert NonZeroNativeValue();
             uint256 reservesBefore = reservesOf[currency];
             reservesOf[currency] = currency.balanceOfSelf();
             paid = reservesOf[currency] - reservesBefore;
@@ -297,26 +300,6 @@ contract PoolManager is IPoolManager, ProtocolFees, NoDelegateCall, ERC6909Claim
         pools[id].setSwapFee(newDynamicSwapFee);
     }
 
-    function extsload(bytes32 slot) external view returns (bytes32 value) {
-        /// @solidity memory-safe-assembly
-        assembly {
-            value := sload(slot)
-        }
-    }
-
-    function extsload(bytes32 startSlot, uint256 nSlots) external view returns (bytes memory) {
-        bytes memory value = new bytes(32 * nSlots);
-
-        /// @solidity memory-safe-assembly
-        assembly {
-            for { let i := 0 } lt(i, nSlots) { i := add(i, 1) } {
-                mstore(add(value, mul(add(i, 1), 32)), sload(add(startSlot, i)))
-            }
-        }
-
-        return value;
-    }
-
     function getNonzeroDeltaCount() external view returns (uint256 _nonzeroDeltaCount) {
         return NonZeroDeltaCount.read();
     }

src/interfaces/IExtsload.sol

@@ -0,0 +1,15 @@
+// SPDX-License-Identifier: MIT
+pragma solidity >=0.6.0;
+
+interface IExtsload {
+    /// @notice Called by external contracts to access granular pool state
+    /// @param slot Key of slot to sload
+    /// @return value The value of the slot as bytes32
+    function extsload(bytes32 slot) external view returns (bytes32 value);
+
+    /// @notice Called by external contracts to access granular pool state
+    /// @param slot Key of slot to start sloading from
+    /// @param nSlots Number of slots to load into return value
+    /// @return value The value of the sload-ed slots concatenated as dynamic bytes
+    function extsload(bytes32 slot, uint256 nSlots) external view returns (bytes memory value);
+}

src/interfaces/IPoolManager.sol

@@ -10,8 +10,9 @@ import {IProtocolFees} from "./IProtocolFees.sol";
 import {BalanceDelta} from "../types/BalanceDelta.sol";
 import {PoolId} from "../types/PoolId.sol";
 import {Position} from "../libraries/Position.sol";
+import {IExtsload} from "./IExtsload.sol";
 
-interface IPoolManager is IProtocolFees, IERC6909Claims {
+interface IPoolManager is IProtocolFees, IERC6909Claims, IExtsload {
     /// @notice Thrown when a currency is not netted out after the contract is unlocked
     error CurrencyNotSettled();
 
@@ -36,6 +37,9 @@ interface IPoolManager is IProtocolFees, IERC6909Claims {
     /// or on a pool that does not have a dynamic swap fee.
     error UnauthorizedDynamicSwapFeeUpdate();
 
+    ///@notice Thrown when native currency is passed to a non native settlement
+    error NonZeroNativeValue();
+
     /// @notice Emitted when a new pool is initialized
     /// @param id The abi encoded hash of the pool key struct for the new pool
     /// @param currency0 The first currency of the pool by address sort order
@@ -157,10 +161,11 @@ interface IPoolManager is IProtocolFees, IERC6909Claims {
     /// @param key The pool to modify liquidity in
     /// @param params The parameters for modifying the liquidity
     /// @param hookData Any data to pass to the callback, via `IUnlockCallback(msg.sender).unlockCallback(data)`
-    /// @return delta The balance delta of the liquidity
+    /// @return delta The balance delta of the liquidity change
+    /// @return feeDelta The balance delta of the fees generated in the liquidity range
     function modifyLiquidity(PoolKey memory key, ModifyLiquidityParams memory params, bytes calldata hookData)
         external
-        returns (BalanceDelta);
+        returns (BalanceDelta, BalanceDelta);
 
     struct SwapParams {
         bool zeroForOne;
@@ -193,15 +198,4 @@ interface IPoolManager is IProtocolFees, IERC6909Claims {
 
     /// @notice Updates the pools swap fees for the a pool that has enabled dynamic swap fees.
     function updateDynamicSwapFee(PoolKey memory key, uint24 newDynamicSwapFee) external;
-
-    /// @notice Called by external contracts to access granular pool state
-    /// @param slot Key of slot to sload
-    /// @return value The value of the slot as bytes32
-    function extsload(bytes32 slot) external view returns (bytes32 value);
-
-    /// @notice Called by external contracts to access granular pool state
-    /// @param slot Key of slot to start sloading from
-    /// @param nSlots Number of slots to load into return value
-    /// @return value The value of the sload-ed slots concatenated as dynamic bytes
-    function extsload(bytes32 slot, uint256 nSlots) external view returns (bytes memory value);
 }

src/libraries/LiquidityMath.sol

@@ -0,0 +1,20 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+pragma solidity ^0.8.20;
+
+/// @title Math library for liquidity
+library LiquidityMath {
+    /// @notice Add a signed liquidity delta to liquidity and revert if it overflows or underflows
+    /// @param x The liquidity before change
+    /// @param y The delta by which liquidity should be changed
+    /// @return z The liquidity delta
+    function addDelta(uint128 x, int128 y) internal pure returns (uint128 z) {
+        assembly {
+            z := add(x, y)
+            if shr(128, z) {
+                // revert SafeCastOverflow()
+                mstore(0, 0x93dafdf1)
+                revert(0x1c, 0x04)
+            }
+        }
+    }
+}

src/libraries/Pool.sol

@@ -11,6 +11,7 @@ import {SqrtPriceMath} from "./SqrtPriceMath.sol";
 import {SwapMath} from "./SwapMath.sol";
 import {BalanceDelta, toBalanceDelta} from "../types/BalanceDelta.sol";
 import {ProtocolFeeLibrary} from "./ProtocolFeeLibrary.sol";
+import {LiquidityMath} from "./LiquidityMath.sol";
 
 library Pool {
     using SafeCast for *;
@@ -151,10 +152,11 @@ library Pool {
     /// @notice Effect changes to a position in a pool
     /// @dev PoolManager checks that the pool is initialized before calling
     /// @param params the position details and the change to the position's liquidity to effect
-    /// @return result the deltas of the token balances of the pool
+    /// @return delta the deltas of the token balances of the pool, from the liquidity change
+    /// @return feeDelta the fees generated by the liquidity range
     function modifyLiquidity(State storage self, ModifyLiquidityParams memory params)
         internal
-        returns (BalanceDelta result)
+        returns (BalanceDelta delta, BalanceDelta feeDelta)
     {
         int128 liquidityDelta = params.liquidityDelta;
         int24 tickLower = params.tickLower;
@@ -214,27 +216,25 @@ library Pool {
             if (tick < tickLower) {
                 // current tick is below the passed range; liquidity can only become in range by crossing from left to
                 // right, when we'll need _more_ currency0 (it's becoming more valuable) so user must provide it
-                result = toBalanceDelta(
+                delta = toBalanceDelta(
                     SqrtPriceMath.getAmount0Delta(
                         TickMath.getSqrtRatioAtTick(tickLower), TickMath.getSqrtRatioAtTick(tickUpper), liquidityDelta
                     ).toInt128(),
                     0
                 );
             } else if (tick < tickUpper) {
-                result = toBalanceDelta(
+                delta = toBalanceDelta(
                     SqrtPriceMath.getAmount0Delta(sqrtPriceX96, TickMath.getSqrtRatioAtTick(tickUpper), liquidityDelta)
                         .toInt128(),
                     SqrtPriceMath.getAmount1Delta(TickMath.getSqrtRatioAtTick(tickLower), sqrtPriceX96, liquidityDelta)
                         .toInt128()
                 );
 
-                self.liquidity = liquidityDelta < 0
-                    ? self.liquidity - uint128(-liquidityDelta)
-                    : self.liquidity + uint128(liquidityDelta);
+                self.liquidity = LiquidityMath.addDelta(self.liquidity, liquidityDelta);
             } else {
                 // current tick is above the passed range; liquidity can only become in range by crossing from right to
                 // left, when we'll need _more_ currency1 (it's becoming more valuable) so user must provide it
-                result = toBalanceDelta(
+                delta = toBalanceDelta(
                     0,
                     SqrtPriceMath.getAmount1Delta(
                         TickMath.getSqrtRatioAtTick(tickLower), TickMath.getSqrtRatioAtTick(tickUpper), liquidityDelta
@@ -244,7 +244,7 @@ library Pool {
         }
 
         // Fees earned from LPing are added to the user's currency delta.
-        result = result + toBalanceDelta(feesOwed0.toInt128(), feesOwed1.toInt128());
+        feeDelta = toBalanceDelta(feesOwed0.toInt128(), feesOwed1.toInt128());
     }
 
     struct SwapCache {
@@ -415,9 +415,7 @@ library Pool {
                         if (zeroForOne) liquidityNet = -liquidityNet;
                     }
 
-                    state.liquidity = liquidityNet < 0
-                        ? state.liquidity - uint128(-liquidityNet)
-                        : state.liquidity + uint128(liquidityNet);
+                    state.liquidity = LiquidityMath.addDelta(state.liquidity, liquidityNet);
                 }
 
                 unchecked {
@@ -526,9 +524,7 @@ library Pool {
             liquidityNetBefore := shr(128, liquidity)
         }
 
-        liquidityGrossAfter = liquidityDelta < 0
-            ? liquidityGrossBefore - uint128(-liquidityDelta)
-            : liquidityGrossBefore + uint128(liquidityDelta);
+        liquidityGrossAfter = LiquidityMath.addDelta(liquidityGrossBefore, liquidityDelta);
 
         flipped = (liquidityGrossAfter == 0) != (liquidityGrossBefore == 0);
 

src/libraries/Position.sol

@@ -3,6 +3,7 @@ pragma solidity ^0.8.20;
 
 import {FullMath} from "./FullMath.sol";
 import {FixedPoint128} from "./FixedPoint128.sol";
+import {LiquidityMath} from "./LiquidityMath.sol";
 
 /// @title Position
 /// @notice Positions represent an owner address' liquidity between a lower and upper tick boundary
@@ -63,8 +64,7 @@ library Position {
             if (liquidity == 0) revert CannotUpdateEmptyPosition(); // disallow pokes for 0 liquidity positions
             liquidityNext = liquidity;
         } else {
-            liquidityNext =
-                liquidityDelta < 0 ? liquidity - uint128(-liquidityDelta) : liquidity + uint128(liquidityDelta);
+            liquidityNext = LiquidityMath.addDelta(liquidity, liquidityDelta);
         }
 
         // calculate accumulated fees. overflow in the subtraction of fee growth is expected

src/test/LiquidityMathTest.sol

@@ -0,0 +1,10 @@
+// SPDX-License-Identifier: UNLICENSED
+pragma solidity ^0.8.20;
+
+import {LiquidityMath} from "../libraries/LiquidityMath.sol";
+
+contract LiquidityMathTest {
+    function addDelta(uint128 x, int128 y) external pure returns (uint128 z) {
+        return LiquidityMath.addDelta(x, y);
+    }
+}