JPEG'd contest - rokinot's results

NFTEscrow.sol

https://github.com/code-423n4/2022-04-jpegd/blob/main/contracts/escrow/NFTEscrow.sol#L91

Utilizing keccak256 over sha256 for your salt will significantly decrease gas usage.

LPFarming.sol

https://github.com/code-423n4/2022-04-jpegd/blob/main/contracts/farming/LPFarming.sol#L256

This function is somewhat redundant and can be removed for more efficient gas, although you might want to keep it due to a slightly improved readability.

https://github.com/code-423n4/2022-04-jpegd/blob/main/contracts/farming/LPFarming.sol#L348

Use ++i instead of i++ in for loops.

StrategyPUSDConvex.sol

https://github.com/code-423n4/2022-04-jpegd/blob/main/contracts/vaults/yVault/strategies/StrategyPUSDConvex.sol#L145

Use ++i instead of i++ in for loops.

https://github.com/code-423n4/2022-04-jpegd/blob/main/contracts/vaults/yVault/strategies/StrategyPUSDConvex.sol#L262

Based on the logic of the function and the @notice above it, it's unlikely an hypotethical circumstance would require the controller to know which strategy token IERC20 was sent here. With this in mind, these five require functions can be condensed into a single requirement, which consumes less gas. An example of a possible substition is given below:

require(want != _asset && pusd != _asset && usdc != _asset && weth != _asset && jpeg != _asset, "strategy_token");

Controller.sol

https://github.com/code-423n4/2022-04-jpegd/blob/main/contracts/vaults/yVault/Controller.sol#L69

approveStrategy and revokeStrategy are the only functions allowed to modify the state of approvedStrategies[_token][_strategy]. Keep in mind that state variables, mappings included, are all initialized as 0 in solidity by default, which means all mappings will default to false.

You can save gas by removing both require functions from revokeStrategy, since address(0) will never pass as an approved strategy.

In other words, it's not necessary to check if the token or the address is valid to revoke the strategy, since only valid tokens and addresses will be set to true anyway.

NFTVault.sol

https://github.com/code-423n4/2022-04-jpegd/blob/main/contracts/vaults/NFTVault.sol#L181

https://github.com/code-423n4/2022-04-jpegd/blob/main/contracts/vaults/NFTVault.sol#L184

Use ++i and ++j consecutively for loops.