Gas Optimizations

[code423n4]

Gas Report

G-01: cache array length in for loops

When looping over an array the condition of the loop is checked for every iteration. If you read the length of a storage variable multiple times it can get quite expensive. Instead, cache the length of memory and check that.

// bad
for (uint i; i < arr.length; i++) {

}

// good
uint length = arr.length;
for (uint i; i < length; i++) {

}

There are quite a number of instances where this can be used. Just search for "for (" and you'll find them.

G-02: cache storage variables that are read multiple times within a function

Whenever you read the same storage variable twice, you should cache it in memory. It will save you a SLOAD.

An example would be platformFee in _earmarkRewards() L526-L528

[GalloDaSballo]

Less than 200 gas saved

[GalloDaSballo]

Very basic against even the other "less than 500 gas" reports