less gas using unchecked

[code423n4]

Handle

Tomio

Vulnerability details

Impact

Cheaper gas using unchecked in MathLib.sol

Proof of Concept

https://github.com/code-423n4/2022-01-elasticswap/blob/main/elasticswap/src/libraries/MathLib.sol#L42

Tools Used

Remix

Recommended Mitigation Steps

example before:

function wDiv(uint256 a, uint256 b) public pure returns (uint256) {
        return ((a * WAD) + (b / 2)) / b;
    }

gas cost 22863

after

function wDiv(uint256 a, uint256 b) public pure returns (uint256) {

        unchecked{
        return ((a * WAD) + (b / 2)) / b;
        }

gas cost 22205

[0xean]

dupe of #177