Omniscia Steadefi Audit

GMXPerpetualDEXLongManager Code Style Findings

GMD-01C: Inefficient Code Repetition

Type	Severity	Location
Gas Optimization		GMXPerpetualDEXLongManager.sol:L111-L123

Description:

The referenced lines of code are executed by the GMXPerpetualDEXLongManager::getTotalUsdgAmount function.

Example:

contracts/vaults/gmx/GMXPerpetualDEXLongManager.sol

110function currentTokenWeight(address _token) public view returns (uint256) {
111  uint256 length = gmxVault.allWhitelistedTokensLength();
112  uint256 usdgSupply;
113
114  address whitelistedToken;
115  bool isWhitelisted;
116
117  for (uint256 i = 0; i < length; i++) {
118    whitelistedToken = gmxVault.allWhitelistedTokens(i);
119    isWhitelisted = gmxVault.whitelistedTokens(whitelistedToken);
120    if (isWhitelisted) {
121      usdgSupply += gmxVault.usdgAmounts(whitelistedToken);
122    }
123  }
124  return gmxVault.usdgAmounts(_token) * SAFE_MULTIPLIER / usdgSupply;
125}

Recommendation:

We advise the function to be invoked within GMXPerpetualDEXLongManager::currentTokenWeight, optimizing its execution cost.

Alleviation (4325253d6de0ea91c1e9fb9e01d2e7e98f3d83a9):

The latest code block of GMXPerpetualDEXLongManager::currentTokenWeight correctly invokes GMXPerpetualDEXLongManager::getTotalUsdgAmount minimizing its bytecode size.

GMD-02C: Inefficient Token Weight Assessment

Type	Severity	Location
Gas Optimization		GMXPerpetualDEXLongManager.sol:L185

Description:

The GMXPerpetualDEXLongManager::assetInfo function calculates the total USDG supply and then proceeds to re-calculate it on each GMXPerpetualDEXLongManager::currentTokenWeight invocation it performs.

Example:

contracts/vaults/gmx/GMXPerpetualDEXLongManager.sol

161// get total supply of USDG
162uint256 usdgSupply = getTotalUsdgAmount();
163
164// calculate manager's glp amt in USDG
165uint256 glpAmtInUsdg = (lpTokenBal * SAFE_MULTIPLIER /
166                        glpTotalSupply)
167                        * usdgSupply
168                        / SAFE_MULTIPLIER;
169
170uint256 length = gmxVault.allWhitelistedTokensLength();
171address[] memory tokenAddress = new address[](length);
172uint256[] memory tokenAmt = new uint256[](length);
173
174address whitelistedToken;
175bool isWhitelisted;
176uint256 tokenWeight;
177
178for (uint256 i = 0; i < length; i++) {
179  // check if token is whitelisted
180  whitelistedToken = gmxVault.allWhitelistedTokens(i);
181  isWhitelisted = gmxVault.whitelistedTokens(whitelistedToken);
182  if (isWhitelisted) {
183    tokenAddress[i] = whitelistedToken;
184    // calculate token weight expressed in token amt
185    tokenWeight = currentTokenWeight(whitelistedToken);

Recommendation:

We advise the code to instead assess the current token weight of a whitelisted token directly by replicating the calculation of GMXPerpetualDEXLongManager::currentTokenWeight with the usdgSupply local variable.

Alleviation (7c9b2b09dbe1f75d8c5ad379e658030ecf1be3a0):

The code has been optimized as advised, making use of the local usdgSupply variable and significantly reducing the gas cost of the referenced function.

GMD-03C: Loop Iterator Optimizations

Type	Severity	Location
Gas Optimization		GMXPerpetualDEXLongManager.sol:L117, L142, L178, L209

Description:

The linked for loops increment / decrement their iterator "safely" due to Solidity's built - in safe arithmetics(post - 0.8.X).

Example:

contracts/vaults/gmx/GMXPerpetualDEXLongManager.sol

117for (uint256 i = 0; i < length; i++) {

Recommendation:

We advise the increment / decrement operations to be performed in an unchecked code block as the last statement within each for loop to optimize their execution cost.

Alleviation (4325253d6de0ea91c1e9fb9e01d2e7e98f3d83a9):

All iterator increment statements have been relocated to unchecked code blocks at the end of each respective for loop's body, optimizing their gas cost.

GMD-04C: Repetition of Statements

Type	Severity	Location
Gas Optimization		GMXPerpetualDEXLongManager.sol:L235-L240, L257-L262

Description:

The ManagerAction.Deposit and ManagerAction.AddLiquidity flows are identical within GMXPerpetualDEXLongManager::work.

Example:

contracts/vaults/gmx/GMXPerpetualDEXLongManager.sol

234// ********** Deposit Flow **********
235if (_action == ManagerAction.Deposit) {
236  // borrow from lending pool
237  _borrow(_borrowTokenAmt);
238  // add tokens to LP receive LP tokens and stake
239  _addLiquidity();
240}
241
242// ********** Withdraw Flow **********
243if (_action == ManagerAction.Withdraw) {
244  if (_lpAmt > 0) {
245    // If estimated LP amount is more than actual LP amount owned
246    if (_lpAmt > lpTokenAmt()) {
247      _lpAmt = lpTokenAmt();
248    }
249    // remove LP receive token
250    _removeLiquidity(_lpAmt);
251    // repay lending pool
252    _repay(_repayTokenAmt);
253  }
254}
255
256// ********** Rebalance: Add Liquidity Flow **********
257if (_action == ManagerAction.AddLiquidity) {
258  // Borrow from lending pool
259  _borrow(_borrowTokenAmt);
260  // Add tokens to lp receive lp tokens
261  _addLiquidity();
262}

Recommendation:

We advise their conditionals to be merged with an else (||) clause, optimizing the codebase.

Alleviation (4325253d6de0ea91c1e9fb9e01d2e7e98f3d83a9):

The code branches of ManagerAction.AddLiquidity and ManagerAction.Deposit have been merged to the same if block as per our recommendation.

GMD-05C: Variable Mutability Specifiers (Immutable)

Type	Severity	Location
Gas Optimization		GMXPerpetualDEXLongManager.sol:L64-L71

Description:

The linked variables are assigned to only once during the contract's constructor.

Example:

contracts/vaults/gmx/GMXPerpetualDEXLongManager.sol

54constructor(
55  IGMXPerpetualDEXLongVault _vault,
56  ILendingPool _tokenLendingPool,
57  IGMXRewardRouterHandler _rewardRouterHandler,
58  IGMXRewardRouter _rewardRouter,
59  IGMXStakePool _stakePool,
60  IGMXGLPManager _glpManager,
61  IGMXRewardReader _rewardReader,
62  IGMXVault _gmxVault
63) {
64  vault = _vault;
65  tokenLendingPool = _tokenLendingPool;
66  rewardRouterHandler = _rewardRouterHandler;
67  rewardRouter = _rewardRouter;
68  stakePool = _stakePool;
69  glpManager = _glpManager;
70  rewardReader = _rewardReader;
71  gmxVault = _gmxVault;
72  IERC20(rewardRouter.weth()).approve(address(glpManager), type(uint256).max);
73  IERC20(token()).approve(address(glpManager), type(uint256).max);
74  IERC20(token()).approve(address(tokenLendingPool), type(uint256).max);
75}

Recommendation:

We advise them to be set as immutable greatly optimizing their read-access gas cost.

Alleviation (4325253d6de0ea91c1e9fb9e01d2e7e98f3d83a9):

All variables have been set as immutable per our recommendation, greatly reducing their read-access gas cost.

Omniscia Steadefi Audit

GMXPerpetualDEXLongManager Code Style Findings

GMXPerpetualDEXLongManager Code Style Findings

GMD-01C: Inefficient Code Repetition

Description:

Example:

Recommendation:

Alleviation (4325253d6de0ea91c1e9fb9e01d2e7e98f3d83a9):

GMD-02C: Inefficient Token Weight Assessment

Description:

Example:

Recommendation:

Alleviation (7c9b2b09dbe1f75d8c5ad379e658030ecf1be3a0):

GMD-03C: Loop Iterator Optimizations

Description:

Example:

Recommendation:

Alleviation (4325253d6de0ea91c1e9fb9e01d2e7e98f3d83a9):

GMD-04C: Repetition of Statements

Description:

Example:

Recommendation:

Alleviation (4325253d6de0ea91c1e9fb9e01d2e7e98f3d83a9):

GMD-05C: Variable Mutability Specifiers (Immutable)

Description:

Example:

Recommendation:

Alleviation (4325253d6de0ea91c1e9fb9e01d2e7e98f3d83a9):

ChainLinkOracle.sol (CLO-C)

GMXPerpetualDEXLongReader.sol (GMP-C)

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