Gas Optimizations

[code423n4]

Redundant Operation

Description

address(this).balance - _fromBalance is found to be operated twice while it could be operated once and save the result to a local variable for later use.

Permalinks

• https://github.com/code-423n4/2022-03-lifinance/blob/699c2305fcfb6fe8862b75b26d1d8a2f46a551e6/src/Facets/AnyswapFacet.sol#L101
• https://github.com/code-423n4/2022-03-lifinance/blob/699c2305fcfb6fe8862b75b26d1d8a2f46a551e6/src/Facets/AnyswapFacet.sol#L103

Mitigation

For greater gas-optimization, the code can be rewrite as following:

/* from */
require(address(this).balance - _fromBalance >= _anyswapData.amount, "ERR_INVALID_AMOUNT");
uint256 _postSwapBalance = address(this).balance - _fromBalance;
require(_postSwapBalance > 0, "ERR_INVALID_AMOUNT");

/* to */
uint256 _postSwapBalance = address(this).balance - _fromBalance;
require(_postSwapBalance >= _anyswapData.amount && _postSwapBalance > 0, "ERR_INVALID_AMOUNT");

[gzeoneth]

Warden submitted multiple QA report #149