Gas Optimizations

[code423n4]

Save gas in for loops by unchecked arithmetic

The for loop has no overflow risk of i. Use an unchecked block to save gas.

Proof of Concept

AuraVestedEscrow.sol
100:        for (uint256 i = 0; i < _recipient.length; i++) {

ExtraRewardsDistributor.sol
233:        for (uint256 i = epochIndex; i < tokenEpochs; i++) {

AuraLocker.sol
174:            for (uint256 i = 0; i < rewardTokensLength; i++) {
306:        for (uint256 i; i < rewardTokensLength; i++) {
410:            for (uint256 i = nextUnlockIndex; i < length; i++) {
664:        for (uint256 i = locksLength; i > 0; i--) {
696:        for (uint256 i = nextUnlockIndex; i < locks.length; i++) {
726:        for (uint256 i = epochIndex + 1; i > 0; i--) {
773:        for (uint256 i = 0; i < userRewardsLength; i++) {

AuraClaimZap.sol
143:        for (uint256 i = 0; i < rewardContracts.length; i++) {
147:        for (uint256 i = 0; i < extraRewardContracts.length; i++) {
151:        for (uint256 i = 0; i < tokenRewardContracts.length; i++) {

Recommendation

Use unchecked blocks to avoid overflow checks, or use ++i rather than i++ if you don't use unchecked blocks.

for (uint256 i = 0; i < length; ) {
    ...
    unchecked {
        ++i;
    }
}