Gas Optimizations

[code423n4]

GAS

1. repetition in the same boolean operation

summary

POC https://github.com/code-423n4/2022-04-jpegd/blob/main/contracts/vaults/NFTVault.sol#L699-L728

before '''

require( position.borrowType == BorrowType.NOT_CONFIRMED ||
    (position.borrowType == BorrowType.USE_INSURANCE && _useInsurance) ||
    (position.borrowType == BorrowType.NON_INSURANCE && !_useInsurance),
        "invalid_insurance_mode"
    );

if (position.borrowType == BorrowType.USE_INSURANCE || _useInsurance) {
    //some codes
}

if (position.borrowType == BorrowType.NOT_CONFIRMED) {
    //some codes
}

'''

after '''

bool isNotConfirmed =  position.borrowType == BorrowType.NOT_CONFIRMED;
bool isUseInsurance = position.borrowType == BorrowType.USE_INSURANCE;
bool isNotUseInsurance = position.borrowType == BorrowType.NON_INSURANCE;

require( isNotConfirmed  ||
    (isUseInsurance && _useInsurance) ||
    (isNotUseInsurance && !_useInsurance),
        "invalid_insurance_mode"
    );

if (isUseInsurance || _useInsurance) {
    //some code s
}

if (isNotConfirmed) {
    //some codes
}

'''

2. return the same address

summary

whether the nft is owned by this contract or not, it will return the same address. so that this conditional statement can be omitted to save gas

POC https://github.com/code-423n4/2022-04-jpegd/blob/main/contracts/helpers/CryptoPunksHelper.sol#L31

before '''

address account = ICryptoPunks(nftAddress).punkIndexToAddress(_idx);
return account == address(this) ? owner() : account;

'''

after '''

address account = ICryptoPunks(nftAddress).punkIndexToAddress(_idx);
return account;

'''