| Issue | Contexts | Estimated Gas Saved | |
|---|---|---|---|
| GAS‑1 | abi.encode() is less efficient than abi.encodepacked() |
6 | 600 |
| GAS‑2 | Setting the constructor to payable |
5 | 65 |
| GAS‑3 | Duplicated require()/revert() Checks Should Be Refactored To A Modifier Or Function |
2 | 56 |
| GAS‑4 | Use assembly to write address storage values |
15 | - |
| GAS‑5 | Use hardcoded address instead address(this) |
16 | - |
| GAS‑6 | Optimize names to save gas | 9 | 198 |
| GAS‑7 | <x> += <y> Costs More Gas Than <x> = <x> + <y> For State Variables |
10 | - |
| GAS‑8 | Public Functions To External | 8 | - |
| GAS‑9 | Splitting require() Statements That Use && Saves Gas |
2 | 18 |
| GAS‑10 | Usage of uints/ints smaller than 32 bytes (256 bits) incurs overhead |
25 | - |
| GAS‑11 | Using unchecked blocks to save gas |
3 | 408 |
| GAS‑12 | Use solidity version 0.8.17 to gain some gas boost | 15 | 1320 |
| GAS‑13 | Using storage instead of memory saves gas |
4 | 1400 |
Total: 159 contexts over 22 issues
See for more information: https://github.com/ConnorBlockchain/Solidity-Encode-Gas-Comparison
82: lendgine = address(new Lendgine{ salt: keccak256(abi.encode(token0, token1, token0Exp, token1Exp, upperBound)) }());https://github.com/code-423n4/2023-01-numoen/tree/main/src/core/Factory.sol#L82
150: abi.encode(https://github.com/code-423n4/2023-01-numoen/tree/main/src/periphery/LendgineRouter.sol#L150
268: abi.encode(https://github.com/code-423n4/2023-01-numoen/tree/main/src/periphery/LendgineRouter.sol#L268
160: abi.encode(https://github.com/code-423n4/2023-01-numoen/tree/main/src/periphery/LiquidityManager.sol#L160
108: abi.encode(params.tokenIn)https://github.com/code-423n4/2023-01-numoen/tree/main/src/periphery/SwapHelper.sol#L108
28: keccak256(abi.encode(token0, token1, token0Exp, token1Exp, upperBound)),Saves ~13 gas per instance
27: constructor()https://github.com/code-423n4/2023-01-numoen/tree/main/src/core/ImmutableState.sol#L27
49: constructor(
address _factory,
address _uniswapV2Factory,
address _uniswapV3Factory,
address _weth
)
SwapHelper(_uniswapV2Factory, _uniswapV3Factory)
Payment(_weth)https://github.com/code-423n4/2023-01-numoen/tree/main/src/periphery/LendgineRouter.sol#L49
75: constructor(address _factory, address _weth) Payment(_weth)https://github.com/code-423n4/2023-01-numoen/tree/main/src/periphery/LiquidityManager.sol#L75
17: constructor(address _weth)https://github.com/code-423n4/2023-01-numoen/tree/main/src/periphery/Payment.sol#L17
29: constructor(address _uniswapV2Factory, address _uniswapV3Factory)https://github.com/code-423n4/2023-01-numoen/tree/main/src/periphery/SwapHelper.sol#L29
Saves deployment costs
61: require(reserveIn > 0 && reserveOut > 0, "UniswapV2Library: INSUFFICIENT_LIQUIDITY");
79: require(reserveIn > 0 && reserveOut > 0, "UniswapV2Library: INSUFFICIENT_LIQUIDITY");
135: _totalPositionSize = totalPositionSize; // SLOADhttps://github.com/code-423n4/2023-01-numoen/tree/main/src/core/Lendgine.sol#L135
163: _totalPositionSize = totalPositionSize; // SLOADhttps://github.com/code-423n4/2023-01-numoen/tree/main/src/core/Lendgine.sol#L163
164: _totalLiquidity = totalLiquidity; // SLOADhttps://github.com/code-423n4/2023-01-numoen/tree/main/src/core/Lendgine.sol#L164
214: _totalLiquidityBorrowed = totalLiquidityBorrowed; // SLOADhttps://github.com/code-423n4/2023-01-numoen/tree/main/src/core/Lendgine.sol#L214
247: _totalLiquidityBorrowed = totalLiquidityBorrowed; // SLOADhttps://github.com/code-423n4/2023-01-numoen/tree/main/src/core/Lendgine.sol#L247
267: _rewardPerPositionStored = rewardPerPositionStored; // SLOADhttps://github.com/code-423n4/2023-01-numoen/tree/main/src/core/Lendgine.sol#L267
73: _totalLiquidity = totalLiquidity; // SLOADhttps://github.com/code-423n4/2023-01-numoen/tree/main/src/core/Pair.sol#L73
96: _totalLiquidity = totalLiquidity; // SLOADhttps://github.com/code-423n4/2023-01-numoen/tree/main/src/core/Pair.sol#L96
47: _positionInfo = positionInfo;https://github.com/code-423n4/2023-01-numoen/tree/main/src/core/libraries/Position.sol#L47
Instead of using address(this), it is more gas-efficient to pre-calculate and use the hardcoded address. Foundry's script.sol and solmate's LibRlp.sol contracts can help achieve this.
References: https://book.getfoundry.sh/reference/forge-std/compute-create-address
https://twitter.com/transmissions11/status/1518507047943245824
108: uint256 shares = balanceOf[address(this)];
115: _burn(address(this), shares);
https://github.com/code-423n4/2023-01-numoen/tree/main/src/core/Lendgine.sol#L108
https://github.com/code-423n4/2023-01-numoen/tree/main/src/core/Lendgine.sol#L115
14: token.staticcall(abi.encodeWithSelector(bytes4(keccak256(bytes("balanceOf(address)"))), address(this)));
https://github.com/code-423n4/2023-01-numoen/tree/main/src/libraries/Balance.sol#L14
148: address(this),
https://github.com/code-423n4/2023-01-numoen/tree/main/src/periphery/LendgineRouter.sol#L148
235: if (decoded.recipient != address(this)) {
https://github.com/code-423n4/2023-01-numoen/tree/main/src/periphery/LendgineRouter.sol#L235
262: address recipient = params.recipient == address(0) ? address(this) : params.recipient;
267: address(this),
https://github.com/code-423n4/2023-01-numoen/tree/main/src/periphery/LendgineRouter.sol#L262
https://github.com/code-423n4/2023-01-numoen/tree/main/src/periphery/LendgineRouter.sol#L267
158: address(this),
177: (, uint256 rewardPerPositionPaid,) = ILendgine(lendgine).positions(address(this));
https://github.com/code-423n4/2023-01-numoen/tree/main/src/periphery/LiquidityManager.sol#L158
https://github.com/code-423n4/2023-01-numoen/tree/main/src/periphery/LiquidityManager.sol#L177
206: address recipient = params.recipient == address(0) ? address(this) : params.recipient;
213: (, uint256 rewardPerPositionPaid,) = ILendgine(lendgine).positions(address(this));
https://github.com/code-423n4/2023-01-numoen/tree/main/src/periphery/LiquidityManager.sol#L206
https://github.com/code-423n4/2023-01-numoen/tree/main/src/periphery/LiquidityManager.sol#L213
233: address recipient = params.recipient == address(0) ? address(this) : params.recipient;
237: (, uint256 rewardPerPositionPaid,) = ILendgine(params.lendgine).positions(address(this));
https://github.com/code-423n4/2023-01-numoen/tree/main/src/periphery/LiquidityManager.sol#L233
https://github.com/code-423n4/2023-01-numoen/tree/main/src/periphery/LiquidityManager.sol#L237
45: if (address(this).balance > 0) SafeTransferLib.safeTransferETH(msg.sender, address(this).balance);
https://github.com/code-423n4/2023-01-numoen/tree/main/src/periphery/Payment.sol#L45
53: if (token == weth && address(this).balance >= value) {
57: } else if (payer == address(this)) {
https://github.com/code-423n4/2023-01-numoen/tree/main/src/periphery/Payment.sol#L53
https://github.com/code-423n4/2023-01-numoen/tree/main/src/periphery/Payment.sol#L57
Use hardcoded address
Contracts most called functions could simply save gas by function ordering via Method ID. Calling a function at runtime will be cheaper if the function is positioned earlier in the order (has a relatively lower Method ID) because 22 gas are added to the cost of a function for every position that came before it. The caller can save on gas if you prioritize most called functions.
See more here
All in-scope contracts
Find a lower method ID name for the most called functions for example Call() vs. Call1() is cheaper by 22 gas For example, the function IDs in the Gauge.sol contract will be the most used; A lower method ID may be given.
91: totalLiquidityBorrowed += liquidity;
https://github.com/code-423n4/2023-01-numoen/tree/main/src/core/Lendgine.sol#L91
114: totalLiquidityBorrowed -= liquidity;
https://github.com/code-423n4/2023-01-numoen/tree/main/src/core/Lendgine.sol#L114
176: totalPositionSize -= size;
https://github.com/code-423n4/2023-01-numoen/tree/main/src/core/Lendgine.sol#L176
257: rewardPerPositionStored += FullMath.mulDiv(dilutionSpeculative, 1e18, totalPositionSize);
https://github.com/code-423n4/2023-01-numoen/tree/main/src/core/Lendgine.sol#L257
178: position.tokensOwed += FullMath.mulDiv(position.size, rewardPerPositionPaid - position.rewardPerPositionPaid, 1e18);
180: position.size += size;
https://github.com/code-423n4/2023-01-numoen/tree/main/src/periphery/LiquidityManager.sol#L178
https://github.com/code-423n4/2023-01-numoen/tree/main/src/periphery/LiquidityManager.sol#L180
214: position.tokensOwed += FullMath.mulDiv(position.size, rewardPerPositionPaid - position.rewardPerPositionPaid, 1e18);
216: position.size -= params.size;
https://github.com/code-423n4/2023-01-numoen/tree/main/src/periphery/LiquidityManager.sol#L214
https://github.com/code-423n4/2023-01-numoen/tree/main/src/periphery/LiquidityManager.sol#L216
238: position.tokensOwed += FullMath.mulDiv(position.size, rewardPerPositionPaid - position.rewardPerPositionPaid, 1e18);
242: position.tokensOwed -= amount;
https://github.com/code-423n4/2023-01-numoen/tree/main/src/periphery/LiquidityManager.sol#L238
https://github.com/code-423n4/2023-01-numoen/tree/main/src/periphery/LiquidityManager.sol#L242
The following functions could be set external to save gas and improve code quality. External call cost is less expensive than of public functions.
function getBorrowRate(uint256 borrowedLiquidity, uint256 totalLiquidity) public pure override returns (uint256 rate) {https://github.com/code-423n4/2023-01-numoen/tree/main/src/core/JumpRate.sol#L13
function convertLiquidityToShare(uint256 liquidity) public view override returns (uint256) {https://github.com/code-423n4/2023-01-numoen/tree/main/src/core/Lendgine.sol#L213
function convertShareToLiquidity(uint256 shares) public view override returns (uint256) {https://github.com/code-423n4/2023-01-numoen/tree/main/src/core/Lendgine.sol#L219
function convertCollateralToLiquidity(uint256 collateral) public view override returns (uint256) {https://github.com/code-423n4/2023-01-numoen/tree/main/src/core/Lendgine.sol#L224
function convertLiquidityToCollateral(uint256 liquidity) public view override returns (uint256) {https://github.com/code-423n4/2023-01-numoen/tree/main/src/core/Lendgine.sol#L229
function invariant(uint256 amount0, uint256 amount1, uint256 liquidity) public view override returns (bool) {https://github.com/code-423n4/2023-01-numoen/tree/main/src/core/Pair.sol#L53
function unwrapWETH(uint256 amountMinimum, address recipient) public payable {https://github.com/code-423n4/2023-01-numoen/tree/main/src/periphery/Payment.sol#L25
function sweepToken(address token, uint256 amountMinimum, address recipient) public payable {https://github.com/code-423n4/2023-01-numoen/tree/main/src/periphery/Payment.sol#L35
Instead of using operator && on a single require. Using a two require can save more gas.
i.e.
for require(reserveIn > 0 && reserveOut > 0, "UniswapV2Library: INSUFFICIENT_LIQUIDITY"); use:
require(reserveIn > 0);
require(reserveOut > 0);
61: require(reserveIn > 0 && reserveOut > 0, "UniswapV2Library: INSUFFICIENT_LIQUIDITY");79: require(reserveIn > 0 && reserveOut > 0, "UniswapV2Library: INSUFFICIENT_LIQUIDITY");When using elements that are smaller than 32 bytes, your contract's gas usage may be higher. This is because the EVM operates on 32 bytes at a time. Therefore, if the element is smaller than that, the EVM must use more operations in order to reduce the size of the element from 32 bytes to the desired size.
https://docs.soliditylang.org/en/v0.8.11/internals/layout_in_storage.html
Each operation involving a uint8 costs an extra 22-28 gas (depending on whether the other operand is also a variable of type uint8) as compared to ones involving uint256, due to the compiler having to clear the higher bits of the memory word before operating on the uint8, as well as the associated stack operations of doing so. Use a larger size then downcast where needed
50: uint128 token0Exp;https://github.com/code-423n4/2023-01-numoen/tree/main/src/core/Factory.sol#L50
51: uint128 token1Exp;https://github.com/code-423n4/2023-01-numoen/tree/main/src/core/Factory.sol#L51
30: uint128 _token0Exp;https://github.com/code-423n4/2023-01-numoen/tree/main/src/core/ImmutableState.sol#L30
31: uint128 _token1Exp;https://github.com/code-423n4/2023-01-numoen/tree/main/src/core/ImmutableState.sol#L31
40: uint120 public override reserve0;https://github.com/code-423n4/2023-01-numoen/tree/main/src/core/Pair.sol#L40
43: uint120 public override reserve1;https://github.com/code-423n4/2023-01-numoen/tree/main/src/core/Pair.sol#L43
119: uint120 _reserve0 = reserve0;https://github.com/code-423n4/2023-01-numoen/tree/main/src/core/Pair.sol#L119
120: uint120 _reserve1 = reserve1;https://github.com/code-423n4/2023-01-numoen/tree/main/src/core/Pair.sol#L120
62: uint24 fee;https://github.com/code-423n4/2023-01-numoen/tree/main/src/periphery/SwapHelper.sol#L62
Solidity version 0.8+ comes with implicit overflow and underflow checks on unsigned integers. When an overflow or an underflow isn’t possible (as an example, when a comparison is made before the arithmetic operation), some gas can be saved by using an unchecked block
14: require((z = x - uint256(-y)) < x, "LS");
https://github.com/code-423n4/2023-01-numoen/tree/main/src/core/libraries/PositionMath.sol#L14
107: zeroForOne ? TickMath.MIN_SQRT_RATIO + 1 : TickMath.MAX_SQRT_RATIO - 1,
https://github.com/code-423n4/2023-01-numoen/tree/main/src/periphery/SwapHelper.sol#L107
81: uint256 denominator = (reserveOut - amountOut) * 997;
Upgrade to the latest solidity version 0.8.17 to get additional gas savings.
pragma solidity ^0.8.4;https://github.com/code-423n4/2023-01-numoen/tree/main/src/core/Factory.sol#L2
pragma solidity ^0.8.0;https://github.com/code-423n4/2023-01-numoen/tree/main/src/core/ImmutableState.sol#L2
pragma solidity ^0.8.0;https://github.com/code-423n4/2023-01-numoen/tree/main/src/core/JumpRate.sol#L2
pragma solidity ^0.8.4;https://github.com/code-423n4/2023-01-numoen/tree/main/src/core/Lendgine.sol#L2
pragma solidity ^0.8.4;https://github.com/code-423n4/2023-01-numoen/tree/main/src/core/Pair.sol#L2
pragma solidity ^0.8.4;https://github.com/code-423n4/2023-01-numoen/tree/main/src/core/libraries/Position.sol#L2
pragma solidity >=0.5.0;https://github.com/code-423n4/2023-01-numoen/tree/main/src/core/libraries/PositionMath.sol#L2
pragma solidity ^0.8.4;https://github.com/code-423n4/2023-01-numoen/tree/main/src/libraries/Balance.sol#L2
pragma solidity ^0.8.0;https://github.com/code-423n4/2023-01-numoen/tree/main/src/libraries/SafeCast.sol#L2
pragma solidity ^0.8.4;https://github.com/code-423n4/2023-01-numoen/tree/main/src/periphery/LendgineRouter.sol#L2
pragma solidity ^0.8.4;https://github.com/code-423n4/2023-01-numoen/tree/main/src/periphery/LiquidityManager.sol#L2
pragma solidity ^0.8.4;https://github.com/code-423n4/2023-01-numoen/tree/main/src/periphery/Payment.sol#L2
pragma solidity ^0.8.4;https://github.com/code-423n4/2023-01-numoen/tree/main/src/periphery/SwapHelper.sol#L2
pragma solidity >=0.5.0;pragma solidity >=0.8.0;When fetching data from a storage location, assigning the data to a memory variable causes all fields of the struct/array to be read from storage, which incurs a Gcoldsload (2100 gas) for each field of the struct/array. If the fields are read from the new memory variable, they incur an additional MLOAD rather than a cheap stack read. Instead of declearing the variable with the memory keyword, declaring the variable with the storage keyword and caching any fields that need to be re-read in stack variables, will be much cheaper, only incuring the Gcoldsload for the fields actually read. The only time it makes sense to read the whole struct/array into a memory variable, is if the full struct/array is being returned by the function, is being passed to a function that requires memory, or if the array/struct is being read from another memory array/struct
167: Position.Info memory positionInfo = positions[msg.sender];
https://github.com/code-423n4/2023-01-numoen/tree/main/src/core/Lendgine.sol#L167
175: Position memory position = positions[params.recipient][lendgine];
https://github.com/code-423n4/2023-01-numoen/tree/main/src/periphery/LiquidityManager.sol#L175
211: Position memory position = positions[msg.sender][lendgine];
https://github.com/code-423n4/2023-01-numoen/tree/main/src/periphery/LiquidityManager.sol#L211
235: Position memory position = positions[msg.sender][params.lendgine];
https://github.com/code-423n4/2023-01-numoen/tree/main/src/periphery/LiquidityManager.sol#L235