Juicebox V2 contest - delfin454000's results

JBPayoutRedemptionPaymentTerminal.sol: L594-610

JBPayoutRedemptionPaymentTerminal.sol: L1008-1173

JBPayoutRedemptionPaymentTerminal.sol: L1396-1424

JBSplitsStore.sol: L204-224

Example (JBSplitsStore.sol: L211-221):

      for (uint256 _j = 0; _j < _splits.length; _j++) {
        // Check for sameness.
        if (
          _splits[_j].percent == _currentSplits[_i].percent &&
          _splits[_j].beneficiary == _currentSplits[_i].beneficiary &&
          _splits[_j].allocator == _currentSplits[_i].allocator &&
          _splits[_j].projectId == _currentSplits[_i].projectId &&
          // Allow lock extention.
          _splits[_j].lockedUntil >= _currentSplits[_i].lockedUntil
        ) _includesLocked = true;
      }

Change uint256 _j = 0; to uint256 _j;

Array length should not be looked up in every iteration of a `for` loop

Since calculating the array length costs gas, it's best to read the length of the array from memory before executing the loop

The array length is looked up in every iteration of the nine for loops referenced below:

JBSplitsStore.sol: L211-221

JBSplitsStore.sol: L229-280

JBPayoutRedemptionPaymentTerminal.sol: L1008-1173

JBFundingCycleStore.sol: L724-734

Example (JBSplitsStore.sol: L211-221):

      for (uint256 _j = 0; _j < _splits.length; _j++) {
        // Check for sameness.
        if (
          _splits[_j].percent == _currentSplits[_i].percent &&
          _splits[_j].beneficiary == _currentSplits[_i].beneficiary &&
          _splits[_j].allocator == _currentSplits[_i].allocator &&
          _splits[_j].projectId == _currentSplits[_i].projectId &&
          // Allow lock extention.
          _splits[_j].lockedUntil >= _currentSplits[_i].lockedUntil
        ) _includesLocked = true;
      }

Suggestion:

      uint256 totalSplitsLength = _splits.length; 
      for (uint256 _j = 0; _j < totalSplitsLength; _j++) {
        // Check for sameness.
        if (
          _splits[_j].percent == _currentSplits[_i].percent &&
          _splits[_j].beneficiary == _currentSplits[_i].beneficiary &&
          _splits[_j].allocator == _currentSplits[_i].allocator &&
          _splits[_j].projectId == _currentSplits[_i].projectId &&
          // Allow lock extention.
          _splits[_j].lockedUntil >= _currentSplits[_i].lockedUntil
        ) _includesLocked = true;
      }

Use `++i` instead of `i++` to increase count in a `for` loop

Since use of i++ (or j++ or equivalent counter) cost more gas, it is better to use ++i/++j

i++, _i++ or _j++ is used in the 10 for loops referenced below:

JBSplitsStore.sol: L204-224

JBSplitsStore.sol: L211-221

JBSplitsStore.sol: L229-280

JBSplitsStore.sol: L304-331

JBFundingCycleStore.sol: L724-734

Example (JBSplitsStore.sol: L211-221):

      for (uint256 _j = 0; _j < _splits.length; _j++) {
        // Check for sameness.
        if (
          _splits[_j].percent == _currentSplits[_i].percent &&
          _splits[_j].beneficiary == _currentSplits[_i].beneficiary &&
          _splits[_j].allocator == _currentSplits[_i].allocator &&
          _splits[_j].projectId == _currentSplits[_i].projectId &&
          // Allow lock extention.
          _splits[_j].lockedUntil >= _currentSplits[_i].lockedUntil
        ) _includesLocked = true;
      }

Suggestion:

      for (uint256 _j = 0; _j < _splits.length; ++_j) {
        // Check for sameness.
        if (
          _splits[_j].percent == _currentSplits[_i].percent &&
          _splits[_j].beneficiary == _currentSplits[_i].beneficiary &&
          _splits[_j].allocator == _currentSplits[_i].allocator &&
          _splits[_j].projectId == _currentSplits[_i].projectId &&
          // Allow lock extention.
          _splits[_j].lockedUntil >= _currentSplits[_i].lockedUntil
        ) _includesLocked = true;
      }

Avoid use of default "checked" behavior in a `for` loop

Underflow/overflow checks are made every time i++ (or ++i or equivalent counter) is called. Such checks are unnecessary since i is already limited. Therefore, use unchecked{++i}/unchecked{i++} instead

Default checked behavior is used in the six for loops referenced below:

Example (JBOperatorStore.sol: L165-172):

    for (uint256 _i = 0; _i < _indexes.length; _i++) {
      uint256 _index = _indexes[_i];

      if (_index > 255) revert PERMISSION_INDEX_OUT_OF_BOUNDS();

      // Turn the bit at the index on.
      packed |= 1 << _index;
    }

Suggestion:

    for (uint256 _i = 0; _i < _indexes.length;) {
      uint256 _index = _indexes[_i];

      if (_index > 255) revert PERMISSION_INDEX_OUT_OF_BOUNDS();

      // Turn the bit at the index on.
      packed |= 1 << _index;

      unchecked {
        _i++;
      }
    }

`For` loop gas optimization example

While, for presentation purposes, I have separated the for loop-related gas savings opportunities above, they should be combined. Below I show how all four of the gas saving methods outlined in this submission can be implemented together.

Don't initialize the loop counter to zero
Read the array length before executing the loop
Use ++i rather than i++
Use unchecked ++i