Backd Tokenomics contest - 0x29A's results

QA

Use unchecked lib

PoolMigrationZap.sol

Enforce pattern on loops

You can add the unchecked math lib like you do on the others contracts to safely increment the i var, saving gas and make contract consistent with the others by enforcing the same style.

On PoolMigrationZap.sol#L39-L44 you are doing a unchecked increment in the loop, but in the rest of the code you a different pattern. Add the unchecked math lib and change:

        for (uint256 i; i < oldPoolAddresses_.length; ) {
            migrate(oldPoolAddresses_[i]);
            unchecked {
                ++i;
            }
        }

To;

        for (uint256 i; i < oldPoolAddresses_.length; i = i.uncheckedInc()) {
            migrate(oldPoolAddresses_[i]);
        }

_underlyingNewPools can end with a wrong data

If underlying_ is address(0) then _underlyingNewPools[address(0)] will be fill...

Consider change lines PoolMigrationZap.sol#L26-L27 from:

            _underlyingNewPools[underlying_] = newPool_;
            if (underlying_ == address(0)) continue;

To:

            if (underlying_ == address(0)) continue;
            _underlyingNewPools[underlying_] = newPool_;

ConvexStrategyBase.sol

Change var name to avoid shadow

On line L287 you are declaring variable with the same name, i understang that is for caching, but i recommend to change the variable name, consider changing this;

        address _swapperRouter = address(_swapperRouter);
        IERC20(token_).safeApprove(_swapperRouter, 0);
        IERC20(token_).safeApprove(_swapperRouter, type(uint256).max);

To this;

        address swapperRouter_ = address(_swapperRouter);
        IERC20(token_).safeApprove(swapperRouter_, 0);
        IERC20(token_).safeApprove(swapperRouter_, type(uint256).max);

LiquidityPool.sol

Add check before calling safeApprove

In think you will need a check before doing the safeApprove call on LiquidityPool.sol#L700 Just replace;

IERC20(lpToken_).safeApprove(staker_, type(uint256).max);

With

if (IERC20(lpToken_).allowance(staker_, spender) > 0) return;
IERC20(lpToken_).safeApprove(staker_, type(uint256).max);

_keeperGauge

Missing event emission

Critical function dont emit events; InflationManager.sol#L58-L63:setMinter InflationManager.sol#L89:deactivateWeightBasedKeeperDistribution

Gas optimizations

Use unchecked lib to increment safe variables

PoolMigrationZap.sol

You can add the unchecked math lib like you do on the others contracts to safely increment the i var, saving gas and make contract consistent with the others by enforcing the same style.

Recommendation, add using UncheckedMath for uint256 And on line PoolMigrationZap.sol#L22 change;

for (uint256 i; i < newPools_.length; ++i) {

To

for (uint256 i; i < newPools_.length; i = i.uncheckedInc()) {

TopUpKeeperHelper.sol

On line TopUpKeeperHelper.sol#L52 you coul use unchecked math lib to increment the variable. Change:

topupsAdded++;

To:

topupsAdded = topupsAdded.uncheckedInc();

KeeperGauge.sol

On lines #L98 and L59 you could use unchecked math lib, consider change;

epoch++;

To;

epoch = epoch.uncheckedInc();

Use unchecked for decrement i

On BkdLocker.sol#L140 you can do a unchecked decrement (or add a function to the Unchecked math to do it) change;

i = i - 1;

to;

unchecked { --i; }

Cache .length

You could cache lenght of arrays to save gas; RewardHandler.sol#L41-L42 StakerVault.sol#L259 VestedEscrow.sol#L94

Use require(foo != 0) instead of require(foo > 0)

>0 is less gas efficient than !0 if you enable the optimizer at 10k AND you’re in a require statement.

BkdLocker.sol#L91 BkdLocker.sol#L92 BkdLocker.sol#L137 VestedEscrow.sol#L84 KeeperGauge.sol#L140 AmmGauge.sol#L104 AmmGauge.sol#L125