Maia DAO Ecosystem - naman1778's results

[G-01] Using calldata instead of memory for read-only arguments in external functions saves gas

When a function with a memory array is called externally, the abi.decode() step has to use a for-loop to copy each index of the calldata to the memory index. Each iteration of this for-loop costs at least 60 gas (i.e. 60 * <mem_array>.length). Using calldata directly, obliviates the need for such a loop in the contract code and runtime execution. Note that even if an interface defines a function as having memory arguments, it’s still valid for implementation contracs to use calldata arguments instead.

If the array is passed to an internal function which passes the array to another internal function where the array is modified and therefore memory is used in the external call, it’s still more gass-efficient to use calldata when the external function uses modifiers, since the modifiers may prevent the internal functions from being called. Structs have the same overhead as an array of length one

Note that I’ve also flagged instances where the function is public but can be marked as external since it’s not called by the contract, and cases where a constructor is involved

There are 27 instances of this issue in 13 files

File: src/ulysses-omnichain/factories/ERC20hTokenRootFactory.sol

54: function createToken(string memory _name, string memory _symbol)

https://github.com/code-423n4/2023-05-maia/blob/main/src/ulysses-omnichain/factories/ERC20hTokenRootFactory.sol

File: src/ulysses-omnichain/factories/ERC20hTokenBranchFactory.sol

60: function createToken(string memory _name, string memory _symbol)

https://github.com/code-423n4/2023-05-maia/blob/main/src/ulysses-omnichain/factories/ERC20hTokenBranchFactory.sol

File: src/ulysses-amm/UlyssesToken.sol	

88: function setWeights(uint256[] memory _weights) external nonReentrant onlyOwner {

https://github.com/code-423n4/2023-05-maia/blob/main/src/ulysses-amm/UlyssesToken.sol

File: src/ulysses-omnichain/BaseBranchRouter.sol

65: function callOutAndBridge(bytes calldata params, DepositInput memory dParams, uint128 remoteExecutionGas)

76: function callOutAndBridgeMultiple(
77:    bytes calldata params,
78:    DepositMultipleInput memory dParams,
79:    uint128 remoteExecutionGas
80: ) external payable lock {

112: function anyExecuteSettlement(bytes calldata, SettlementParams memory)

123: function anyExecuteSettlementMultiple(bytes calldata, SettlementMultipleParams memory)

https://github.com/code-423n4/2023-05-maia/blob/main/src/ulysses-omnichain/BaseBranchRouter.sol

File: src/ulysses-omnichain/ArbitrumBranchPort.sol

96: function bridgeInMultiple(address _recipient, address[] memory _localAddresses, uint256[] memory _amounts)

129: function bridgeOutMultiple(
130:     address _depositor,
131:     address[] memory _localAddresses,
132:     address[] memory _underlyingAddresses,
133:     uint256[] memory _amounts,
134:     uint256[] memory _deposits
135: ) external override(IBranchPort, BranchPort) requiresBridgeAgent {

https://github.com/code-423n4/2023-05-maia/blob/main/src/ulysses-omnichain/ArbitrumBranchPort.sol

File: src/ulysses-omnichain/CoreRootRouter.sol

379: function anyExecuteDepositSingle(bytes1, bytes memory, DepositParams memory, uint24)

390: function anyExecuteDepositMultiple(bytes1, bytes calldata, DepositMultipleParams memory, uint24)

400: function anyExecuteSigned(bytes1, bytes memory, address, uint24)

411: function anyExecuteSignedDepositSingle(bytes1, bytes memory, DepositParams memory, address, uint24)

422: function anyExecuteSignedDepositMultiple(bytes1, bytes memory, DepositMultipleParams memory, address, uint24)

https://github.com/code-423n4/2023-05-maia/blob/main/src/ulysses-omnichain/CoreRootRouter.sol

File: src/ulysses-omnichain/BranchPort.sol

226: function bridgeInMultiple(address _recipient, address[] memory _localAddresses, uint256[] memory _amounts)

260: function bridgeOutMultiple(
261:    address _depositor,
262:    address[] memory _localAddresses,
263:    address[] memory _underlyingAddresses,
264:    uint256[] memory _amounts,
265:    uint256[] memory _deposits
266: ) external virtual requiresBridgeAgent {

421: function anyExecuteSignedDepositMultiple(
422:     bytes1 funcId,
423:     bytes memory encodedData,
424:     DepositMultipleParams calldata,
425:     address userAccount,
426:     uint24
427: ) external payable requiresExecutor lock returns (bool success, bytes memory result) {

https://github.com/code-423n4/2023-05-maia/blob/main/src/ulysses-omnichain/BranchPort.sol

File: src/ulysses-omnichain/RootPort.sol	

420: function addNewChain(
421:     address _pledger,
422:     uint256 _pledgedInitialAmount,
423:     address _coreBranchBridgeAgentAddress,
424:     uint24 _chainId,
425:     string memory _wrappedGasTokenName,
426:     string memory _wrappedGasTokenSymbol,
427:     uint24 _fee,
428:     uint24 _priceImpactPercentage,
429:     uint160 _sqrtPriceX96,
430:     address _nonFungiblePositionManagerAddress,
431:     address _newLocalBranchWrappedNativeTokenAddress,
432:     address _newUnderlyingBranchWrappedNativeTokenAddress
433: ) external onlyOwner {

https://github.com/code-423n4/2023-05-maia/blob/main/src/ulysses-omnichain/RootPort.sol

File: src/uni-v3-staker/UniswapV3Staker.sol 

157: function createIncentive(IncentiveKey memory key, uint256 reward) external {

187: function endIncentive(IncentiveKey memory key) external returns (uint256 refund) {

243: function withdrawToken(uint256 tokenId, address to, bytes memory data) external {

287: function getRewardInfo(IncentiveKey memory key, uint256 tokenId)

361: function unstakeToken(IncentiveKey memory key, uint256 tokenId) external {

https://github.com/code-423n4/2023-05-maia/blob/main/src/uni-v3-staker/UniswapV3Staker.sol

File: src/ulysses-omnichain/RootBridgeAgent.sol

275: function callOut(address _recipient, bytes memory _data, uint24 _toChain) external payable lock requiresRouter {

https://github.com/code-423n4/2023-05-maia/blob/main/src/ulysses-omnichain/RootBridgeAgent.sol

File: src/ulysses-omnichain/BranchBridgeAgent.sol

192: function callOutAndBridge(bytes calldata _params, DepositInput memory _dParams, uint128 _remoteExecutionGas)

https://github.com/code-423n4/2023-05-maia/blob/main/src/ulysses-omnichain/BranchBridgeAgent.sol

File: src/talos/factories/TalosBaseStrategyFactory.sol	

55: function createTalosBaseStrategy(
57:     IUniswapV3Pool pool,
58:     ITalosOptimizer optimizer,
59:     address strategyManager,
60:     bytes memory data
61: ) external {

https://github.com/code-423n4/2023-05-maia/blob/main/src/talos/factories/TalosBaseStrategyFactory.sol

File: src/gauges/factories/BaseV2GaugeFactory.sol 

109: function createGauge(address strategy, bytes memory data) external onlyOwner {

https://github.com/code-423n4/2023-05-maia/blob/main/src/gauges/factories/BaseV2GaugeFactory.sol

Test Code

contract GasTest is DSTest {
    Contract0 c0;
    Contract1 c1;
    function setUp() public {
        c0 = new Contract0();
        c1 = new Contract1();
    }
    function testGas() public {
        c0.not_optimized("Naman");
        c1.optimized("Naman");
    }
}

contract Contract0 {

     function not_optimized(string memory a) public returns(string memory){
         return a;
     }
}

contract Contract1 {

     function optimized(string calldata a) public returns(string calldata){
         return a;
     }
}

Gas Report

[G-02] Use abi.encodePacked() instead of abi.encode()

Changing abi.encode function to abi.encodePacked can save gas since the abi.encode function pads extra null bytes at the end of the call data, which is unnecessary. Also, in general, abi.encodePacked is more gas-efficient (see Solidity-Encode-Gas-Comparison).

Consider using abi.encodePacked() here:

Use abi.encodePacked() where possible to save gas

There are 17 instances of this issue in 8 files:

File: src/ulysses-omnichain/ArbitrumCoreBranchRouter.sol

53: abi.encode(_underlyingAddress, address(0), name, symbol);

98: bytes memory data = abi.encode(newBridgeAgent, _rootBridgeAgent);

https://github.com/code-423n4/2023-05-maia/blob/main/src/ulysses-omnichain/ArbitrumCoreBranchRouter.sol

File: src/ulysses-omnichain/CoreBranchRouter.sol 	

48: bytes memory data = abi.encode(msg.sender, _globalAddress, _toChain, _rootExecutionGas);

https://github.com/code-423n4/2023-05-maia/blob/main/src/ulysses-omnichain/CoreBranchRouter.sol

File: src/ulysses-omnichain/CoreRootRouter.sol 

107: bytes memory data = abi.encode(

158: bytes memory data = abi.encode(

238: bytes memory data = abi.encode(_branchBridgeAgentFactory);

259: bytes memory data = abi.encode(_branchBridgeAgent);

282: bytes memory data = abi.encode(_underlyingToken, _minimumReservesRatio);

309: bytes memory data = abi.encode(_portStrategy, _underlyingToken, _dailyManagementLimit, _isUpdateDailyLimit);

https://github.com/code-423n4/2023-05-maia/blob/main/src/ulysses-omnichain/CoreRootRouter.sol

File: src/governance/GovernorBravoDelegateMaia.sol

198: !timelock.queuedTransactions(keccak256(abi.encode(target, value, signature, data, eta))),

346: keccak256(abi.encode(DOMAIN_TYPEHASH, keccak256(bytes(name)), getChainIdInternal(), address(this)));

347: bytes32 structHash = keccak256(abi.encode(BALLOT_TYPEHASH, proposalId, support));

https://github.com/code-423n4/2023-05-maia/blob/main/src/governance/GovernorBravoDelegateMaia.sol

File: src/ulysses-omnichain/RootBridgeAgent.sol

689: abi.encode(SwapCallbackData({tokenIn: gasTokenGlobalAddress}))

733: abi.encode(SwapCallbackData({tokenIn: address(wrappedNativeToken)}))

https://github.com/code-423n4/2023-05-maia/blob/main/src/ulysses-omnichain/RootBridgeAgent.sol

File: src/erc-20/ERC20MultiVotes.sol

368: "\x19\x01", DOMAIN_SEPARATOR(), keccak256(abi.encode(DELEGATION_TYPEHASH, delegatee, nonce, expiry))

https://github.com/code-423n4/2023-05-maia/blob/main/src/erc-20/ERC20MultiVotes.sol

File: src/uni-v3-staker/libraries/IncentiveId.sol

17: return keccak256(abi.encode(key));

https://github.com/code-423n4/2023-05-maia/blob/main/src/uni-v3-staker/libraries/IncentiveId.sol

File: src/talos/libraries/PoolActions.sol	

51: abi.encode(SwapCallbackData({zeroForOne: zeroForOne}))

https://github.com/code-423n4/2023-05-maia/blob/main/src/talos/libraries/PoolActions.sol

Test Code

contract GasTest is DSTest {
    Contract0 c0;
    Contract1 c1;
    function setUp() public {
        c0 = new Contract0();
        c1 = new Contract1();
    }
    function testGas() public {
        c0.not_optimized();
        c1.optimized();
    }
}
contract Contract0 {
    string a = "Code4rena";
    function not_optimized() public returns(bytes32){
        return keccak256(abi.encode(a));
    }
}
contract Contract1 {
    string a = "Code4rena";
    function optimized() public returns(bytes32){
        return keccak256(abi.encodePacked(a));
    }
}

Gas Report

[G-03] Using XOR (^) and OR (|) bitwise equivalents // check for equal to and not equal to

On Remix, given only uint256 types, the following are logical equivalents, but don’t cost the same amount of gas:

(a != b || c != d || e != f) costs 571 ((a ^ b) | (c ^ d) | (e ^ f)) != 0 costs 498 (saving 73 gas) Consider rewriting as following to save gas:

To have a == b means that every 0 and 1 match on both variables. Meaning that a XOR (operator ^) would evaluate to 0 ((a ^ b) == 0), as it excludes by definition any equalities. Now, if a != b, this means that there’s at least somewhere a 1 and a 0 not matching between a and b, making (a ^ b) != 0.

Both formulas are logically equivalent and using the XOR bitwise operator costs actually the same amount of gas:

However, it is much cheaper to use the bitwise OR operator (|) than comparing the truthy or falsy values

There are 7 instances of this issue in 4 files:

File: src/ulysses-omnichain/RootPort.sol 	

494: getUnderlyingTokenFromLocal[_ecoTokenGlobalAddress][localChainId] != address(0)
495:     || getLocalTokenFromUnder[_ecoTokenGlobalAddress][localChainId] != address(0)

https://github.com/code-423n4/2023-05-maia/blob/main/src/ulysses-omnichain/RootPort.sol

File: src/governance/GovernorBravoDelegateMaia.sol

449: msg.sender == admin || msg.sender == whitelistGuardian,

https://github.com/code-423n4/2023-05-maia/blob/main/src/governance/GovernorBravoDelegateMaia.sol

File: src/ulysses-omnichain/RootBridgeAgent.sol

665: if (gasTokenGlobalAddress == address(0) || poolAddress == address(0)) revert InvalidGasPool();

709: if (gasTokenGlobalAddress == address(0) || poolAddress == address(0)) revert InvalidGasPool();

https://github.com/code-423n4/2023-05-maia/blob/main/src/ulysses-omnichain/RootBridgeAgent.sol

File: src/ulysses-omnichain/BranchBridgeAgent.sol

814: _hTokens.length != _tokens.length || _tokens.length != _amounts.length
815:     || _amounts.length != _deposits.length

1243: if ((flag == 0x00) || (flag == 0x01) || (flag == 0x02)) {

1272: } else if ((flag == 0x04) || (flag == 0x05)) {

https://github.com/code-423n4/2023-05-maia/blob/main/src/ulysses-omnichain/BranchBridgeAgent.sol

Test Code

contract GasTest is DSTest {
    Contract0 c0;
    Contract1 c1;
    function setUp() public {
        c0 = new Contract0();
        c1 = new Contract1();
    }
    function testGas() public {
        c0.not_optimized(5,10,16);
        c1.optimized(5,10,16);
    }
}
contract Contract0 {
    address a;
    function not_optimized(uint8 x,uint8 y, uint8 z) public returns(bool){
        if(x!=5 || y!=10 || z!=15){
            return true;
        }
    }
}
contract Contract1 {
    address a;
    function optimized(uint8 x,uint8 y, uint8 z) public returns(bool){
        if(((x^5) | (y^10) | (z^15)) != 0){
            return true;
        }
    }
}

Gas Report

[G-04] Instead of counting down in for statements, count up

Counting down is more gas efficient than counting up in for loop. There are 65 instances of this issue in 20 files:

File: src/ulysses-omnichain/VirtualAccount.sol	

48: for (uint256 i = 0; i < calls.length; i++) {

https://github.com/code-423n4/2023-05-maia/blob/main/src/ulysses-omnichain/VirtualAccount.sol

File: src/ulysses-amm/UlyssesRouter.sol 

78: for (uint256 i = 0; i < length;) {
82:        ++i;

https://github.com/code-423n4/2023-05-maia/blob/main/src/ulysses-amm/UlyssesRouter.sol

File: src/ulysses-amm/UlyssesToken.sol	

95: for (uint256 i = 0; i < assets.length; i++) {

111: for (uint256 i = 0; i < assets.length; i++) {

https://github.com/code-423n4/2023-05-maia/blob/main/src/ulysses-amm/UlyssesToken.sol

File: src/gauges/factories/BaseV2GaugeManager.sol 

64: for (uint256 i = 0; i < length;) {

https://github.com/code-423n4/2023-05-maia/blob/main/src/gauges/factories/BaseV2GaugeManager.sol

File: src/ulysses-amm/factories/UlyssesFactory.sol

99: for (uint256 i = 0; i < length;) {
103:         ++i;

107: for (uint256 i = 0; i < length;) {
119:         ++i;

110: for (uint256 j = 0; j < length;) {    
114:         ++j;

123: for (uint256 i = 0; i < length;) { 
127:         ++i;

145: for (uint256 i = 0; i < length;) {
153:         ++i;

https://github.com/code-423n4/2023-05-maia/blob/main/src/ulysses-amm/factories/UlyssesFactory.sol

File: src/ulysses-omnichain/ArbitrumBranchPort.sol

101: for (uint256 i = 0; i < _localAddresses.length;) {
105:         ++i;

136: for (uint256 i = 0; i < _localAddresses.length;) {
151:         ++i;

https://github.com/code-423n4/2023-05-maia/blob/main/src/ulysses-omnichain/ArbitrumBranchPort.sol

File: src/rewards/rewards/FlywheelGaugeRewards.sol	

176: for (uint256 i = 0; i < size; i++) {

https://github.com/code-423n4/2023-05-maia/blob/main/src/rewards/rewards/FlywheelGaugeRewards.sol

File: src/ulysses-omnichain/BranchPort.sol

231: for (uint256 i = 0; i < _localAddresses.length;) {
235:         ++i;

267: for (uint256 i = 0; i < _localAddresses.length;) {
280:         i++;

https://github.com/code-423n4/2023-05-maia/blob/main/src/ulysses-omnichain/BranchPort.sol

File: src/ulysses-omnichain/RootBridgeAgentExecutor.sol

364: for (uint256 i = 0; i < uint256(uint8(numOfAssets));) {
411:         ++i;

https://github.com/code-423n4/2023-05-maia/blob/main/src/ulysses-omnichain/RootBridgeAgentExecutor.sol

File: src/ulysses-omnichain/MulticallRootRouter.sol	

146: for (uint256 i = 0; i < outputTokens.length;) {
150:         ++i;

311: for (uint256 i = 0; i < outputParams.outputTokens.length;) {
315:         ++i;

387: for (uint256 i = 0; i < outputParams.outputTokens.length;) {
391:         ++i;

463: for (uint256 i = 0; i < outputParams.outputTokens.length;) {
467:         ++i;

https://github.com/code-423n4/2023-05-maia/blob/main/src/ulysses-omnichain/MulticallRootRouter.sol

File: src/governance/GovernorBravoDelegateMaia.sol

181: for (uint256 i = 0; i < proposal.targets.length; i++) {

215: for (uint256 i = 0; i < proposal.targets.length; i++) {

251: for (uint256 i = 0; i < proposal.targets.length; i++) {

https://github.com/code-423n4/2023-05-maia/blob/main/src/governance/GovernorBravoDelegateMaia.sol

File: src/ulysses-amm/UlyssesPool.sol 	

130: for (uint256 i = 1; i < bandwidthStateList.length; i++) {

175: for (uint256 i = 1; i < index; i++) {

189: for (uint256 i = 1; i < index;) {
198:         ++i;

211: for (uint256 i = 1; i <= index; i++) {

232: for (uint256 i = 1; i < bandwidthStateList.length; i++) {

253: for (uint256 i = 1; i < bandwidthStateList.length;) {
265:         ++i;

278: for (uint256 i = 1; i < bandwidthStateList.length;) {
289:         ++i;

296: for (uint256 i = 1; i < bandwidthStateList.length; i++) {

906: for (uint256 i = 1; i < length;) {
931:         ++i;

961: for (uint256 i = 1; i < length;) {
1002:         ++i;

1043: for (uint256 i = 1; i < length;) {
1069:         ++i;

https://github.com/code-423n4/2023-05-maia/blob/main/src/ulysses-amm/UlyssesPool.sol

File: src/ulysses-omnichain/RootBridgeAgent.sol

342: for (uint256 i = 0; i < _globalAddresses.length;) {
354:         ++i;

408: for (uint256 i = 0; i < _dParams.hTokens.length;) {
423:         ++i;

561: for (uint256 i = 0; i < newGas.length;) {
564:         ++i;

596: for (uint256 i = 0; i < settlement.hTokens.length;) {
610:         ++i;

https://github.com/code-423n4/2023-05-maia/blob/main/src/ulysses-omnichain/RootBridgeAgent.sol

File: src/ulysses-omnichain/BranchBridgeAgent.sol

283: for (uint256 i = 0; i < _dParams.hTokens.length; i++) {

580: for (uint256 i = 0; i < numOfAssets;) {
632:         ++i; 

719: for (uint256 i = 0; i < _dParams.hTokens.length; i++) {

951: for (uint256 i = 0; i < deposit.hTokens.length;) {
955:         ++i;

1354: for (uint256 i = 0; i < _deposits.length; i++) {

https://github.com/code-423n4/2023-05-maia/blob/main/src/ulysses-omnichain/BranchBridgeAgent.sol

File: src/gauges/BaseV2Gauge.sol 

114: for (uint256 i = 0; i < length;) {
118:         i++;

https://github.com/code-423n4/2023-05-maia/blob/main/src/gauges/BaseV2Gauge.sol

File: src/gauges/factories/BaseV2GaugeFactory.sol 	

77: for (uint256 i = 0; i < length;) {
81:         i++;

93: for (uint256 i = start; i < end;) {
97:         i++;

https://github.com/code-423n4/2023-05-maia/blob/main/src/gauges/factories/BaseV2GaugeFactory.sol

File: src/erc-4626/ERC4626MultiToken.sol 

50: for (uint256 i = 0; i < length;) {
60:         i++;

68: for (uint256 i = 0; i < length;) {
72:         i++;

79: for (uint256 i = 0; i < length;) {
83:         i++;

170: for (uint256 i = 0; i < length;) {
174:         i++;

201: for (uint256 i = 0; i < length;) {
205:         i++;

216: for (uint256 i = 0; i < length;) {
219:         i++;

235: for (uint256 i = 0; i < length;) {
238:         i++;

250: for (uint256 i = 0; i < length;) {
254:         i++;

https://github.com/code-423n4/2023-05-maia/blob/main/src/erc-4626/ERC4626MultiToken.sol

File: src/erc-20/ERC20Boost.sol 	    

52: for (uint256 i = 0; i < num;) {
55:         i++;

98: for (uint256 i = 0; i < num;) {
101:         i++;

156: for (uint256 i = 0; i < length;) {
166:         i++;

207: for (uint256 i = 0; i < num && i < length;) {
224:         i++;

236: for (uint256 i = 0; i < size;) {
245:         i++;

https://github.com/code-423n4/2023-05-maia/blob/main/src/erc-20/ERC20Boost.sol

File: src/erc-20/ERC20MultiVotes.sol

328: for (uint256 i = 0; i < size && (userFreeVotes + totalFreed) < votes; i++) {

https://github.com/code-423n4/2023-05-maia/blob/main/src/erc-20/ERC20MultiVotes.sol

File: src/erc-20/ERC20Gauges.sol	

114: for (uint256 i = 0; i < num;) {
117:         i++;

155: for (uint256 i = 0; i < num;) {
158:         i++;

259: for (uint256 i = 0; i < size;) {
266:         i++;

338: for (uint256 i = 0; i < size;) {
346:         i++;       

536: for (uint256 i = 0; i < size && (userFreeWeight + totalFreed) < weight;) {
548:         i++;

https://github.com/code-423n4/2023-05-maia/blob/main/src/erc-20/ERC20Gauges.sol

Test Code

contract GasTest is DSTest {
    Contract0 c0;
    Contract1 c1;
    function setUp() public {
        c0 = new Contract0();
        c1 = new Contract1();
    }
    function testGas() public {
        c0.AddNum();
        c1.AddNum();
    }
}


contract Contract0 {
    uint256 num = 3;
    function AddNum() public {
        uint256 _num = num;
        for(uint i=0;i<=9;i++){
            _num = _num +1;
        }
        num = _num;
    }
}


contract Contract1 {
    uint256 num = 3;
    function AddNum() public {
        uint256 _num = num;
        for(uint i=9;i>=0;i--){
            _num = _num +1;
        }
        num = _num;
    }
}

Gas Report

[G-05] Use != 0 instead of > 0

Using > 0 costs more gas than != 0 when used on a uint.

There are 2 instances of this issue in 2 files:

File: src/ulysses-amm/UlyssesToken.sol	

35: require(_weight > 0);

https://github.com/code-423n4/2023-05-maia/blob/main/src/ulysses-amm/UlyssesToken.sol

File: src/erc-4626/ERC4626MultiToken.sol 	

52: require(_weights[i] > 0);

https://github.com/code-423n4/2023-05-maia/blob/main/src/erc-4626/ERC4626MultiToken.sol

Test Code

contract GasTest is DSTest {
    Contract0 c0;
    Contract1 c1;
    function setUp() public {
        c0 = new Contract0();
        c1 = new Contract1();
    }
    function testGas() public {
        c0.not_optimized(5);
        c1.optimized(5);
    }
}

contract Contract0 {
    function not_optimized(uint8 x) public returns(uint8){
        require(x>0,"x is greater than 0");
    }
}

contract Contract1 {
    function optimized(uint8 x) public returns(uint8){
        require(x!=0,"x is greater than 0");
    }
}v

Gas Report

[G-06] Stack variable used as a cheaper cache for a state variable is only used once

If the variable is only accessed once, it’s cheaper to use the state variable directly that one time, and save the 3 gas the extra stack assignment would spend.

There are 5 instances of this issue in 3 files:

File: src/ulysses-amm/UlyssesRouter.sol 

50: UlyssesPool ulysses = getUlyssesLP(poolId);

60: UlyssesPool ulysses = getUlyssesLP(poolId);

https://github.com/code-423n4/2023-05-maia/blob/main/src/ulysses-amm/UlyssesRouter.sol

File: src/gauges/factories/BribesFactory.sol 	

91: uint256 id = bribeFlywheels.length;

https://github.com/code-423n4/2023-05-maia/blob/main/src/gauges/factories/BribesFactory.sol

File: src/ulysses-omnichain/RootPort.sol 	

189: address globalAddress = getGlobalTokenFromLocal[_localAddress][_fromChain];

204: address localAddress = getLocalTokenFromGlobal[_globalAddress][_fromChain];

https://github.com/code-423n4/2023-05-maia/blob/main/src/ulysses-omnichain/RootPort.sol

Test Code

contract GasTest is DSTest {
    Contract0 c0;
    Contract1 c1;
    function setUp() public {
        c0 = new Contract0();
        c1 = new Contract1();
    }
    function testGas() public {
        c0.not_optimized();
        c1.optimized();
    }
}

contract Contract0 {
    uint256 num = 5;
    uint256 sum;
    function not_optimized() public returns(bool){
        uint256 num1 = num;
        sum = num1 + 2;
    }
}

contract Contract1 {
    uint256 num = 5;
    uint256 sum;
    function optimized() public returns(bool){
        sum = num + 2;
    }
}

Gas Report