Gas Optimizations

[code423n4]

1. Don't change storage variable needlessly
   contracts\BkdLocker.sol#L144
   Currently it replaces stashedWithdraws[i] even if "i" equals to "stashedWithdraws.length - 1".
   And it calculates stashedWithdraws.length every time after pop right, you can reduce gas by changing the length variable.
   You can replace L144 like below.

--length;
if(i != length) {
    stashedWithdraws[i] = stashedWithdraws[length];
}

2. Needless conditions.
   contracts\tokenomics\InflationManager.sol#L575
   contracts\tokenomics\InflationManager.sol#L589
   contracts\tokenomics\InflationManager.sol#L602

From the logic of the contract, "totalKeeperPoolWeight" will be always non-negative.
Even if this value could be negative, it will be revoked with underflow error before.

3. Use != 0 instead of > 0 for uint variables
   contracts\BkdLocker.sol#L91
   contracts\BkdLocker.sol#L92
   contracts\BkdLocker.sol#L137
   contracts\BkdLocker.sol#L139
   contracts\BkdLocker.sol#L254
   contracts\BkdLocker.sol#L301
   contracts\tokenomics\AmmGauge.sol#L88
   contracts\tokenomics\AmmGauge.sol#L104
   contracts\tokenomics\AmmGauge.sol#L125
   contracts\tokenomics\AmmGauge.sol#L147
   contracts\tokenomics\FeeBurner.sol#L117
   contracts\tokenomics\KeeperGauge.sol#L140
   contracts\tokenomics\LpGauge.sol#L68
   contracts\tokenomics\LpGauge.sol#L114
   contracts\tokenomics\VestedEscrow.sol#L84
   contracts\RewardHandler.sol#L63

4. Change storage to memory if possible
   contracts\BkdLocker.sol#L251

5. An array’s length should be cached to save gas in for-loops
   contracts\StakerVault.sol#L259
   contracts\tokenomics\FeeBurner.sol#L56
   contracts\tokenomics\InflationManager.sol#L116
   contracts\tokenomics\VestedEscrow.sol#L94
   contracts\zaps\PoolMigrationZap.sol#L22
   contracts\zaps\PoolMigrationZap.sol#L39

6. Usage of unchecked can reduce the gas cost
   contracts\StakerVault.sol#L387

allowances[src][msg.sender] = allowance.uncheckedSub(unstaked);

[GalloDaSballo]

Don't change storage variable needlessly

I don't believe the suggestion will work, in lack of POC I'm not giving it points
The suggested change goes out of bounds (last element of array is array.length - 1)

Needless conditions.

Saves 3 gas
3 * 3 = 9

Use != 0 instead of > 0 for uint variables

Only for Requires, listed below

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

3 * 7 = 21

Change storage to memory if possible

In lack of POC I can't give it any points

An array’s length should be cached to save gas in for-loops

3 per instance

3 * 6 = 18

Usage of unchecked can reduce the gas cost

Would save 20 gas

Total Gas Saved
68