The for loop in Swap.sweepFees() follows this for-each pattern:
for (uint256 i = 0; i < array.length; i++) {
// do something with `array[i]`
}
In such for loops, the array.length is read on every iteration, instead of caching it once in a local variable and read it again using the local variable.
Impact
Calldata reads are a bit more expensive than reading local variables.
Tool Used
Manual code review.
Recommended Mitigation Steps
Read these values from calldata once, cache them in local variables and then read them again using the local variables. For example:
uint256 length = array.length;
for (uint256 i = 0; i < length; i++) {
// do something with `array[i]`
}
This is similar but a different recommendation to #18 as this is referring to the repeated calls to .length which 18 doesn't suggest. Leaving as unique and valid
Handle
pants
Vulnerability details
The for loop in
Swap.sweepFees()
follows this for-each pattern:In such for loops, the
array.length
is read on every iteration, instead of caching it once in a local variable and read it again using the local variable.Impact
Calldata reads are a bit more expensive than reading local variables.
Tool Used
Manual code review.
Recommended Mitigation Steps
Read these values from calldata once, cache them in local variables and then read them again using the local variables. For example: