QuickSwap and StellaSwap contest - emrekocak's results

15000 - 3000 can be changed to 12000 and save some gas

Instead of performing mathematical operations, the result can be written directly.

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In require(), Use != 0 Instead of > 0 With Uint Values

In a require, when checking a uint, using != 0 instead of > 0 saves 6 gas. This will jump over or avoid an extra ISZERO opcode.

Instances include:
src/core/contracts/AlgebraPool.sol:224 src/core/contracts/AlgebraPool.sol:434 src/core/contracts/AlgebraPool.sol:454 src/core/contracts/AlgebraPool.sol:455 src/core/contracts/AlgebraPool.sol:469 src/core/contracts/AlgebraPool.sol:898 src/core/contracts/libraries/PriceMovementMath.sol:52 src/core/contracts/libraries/PriceMovementMath.sol:53

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++i COSTS LESS GAS COMPARED TO i++ OR i += 1

++i costs less gas compared to i++ or i += 1 for unsigned integer, as pre-increment is cheaper (about 5 gas per iteration). This statement is true even with the optimizer enabled.

i++ increments i and returns the initial value of i. Which means:

uint i = 1; i++; // == 1 but i == 2 
But ++i returns the actual incremented value:

uint i = 1; ++i; // == 2 and i == 2 too, so no need for a temporary variable
In the first case, the compiler has to create a temporary variable (when used) for returning 1 instead of 2

Instance includes:

src/core/contracts/libraries/DataStorage.sol:307 I suggest using ++i instead of i++ to increment the value of a uint variable.

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Cache array length in for loops can save gas

Reading array length at each iteration of the loop takes 6 gas (3 for mload and 3 to place memory_offset) in the stack.
Caching the array length in the stack saves around 3 gas per iteration.

Instances include:

src/core/contracts/libraries/DataStorage.sol:307

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Not initializing unit variable to default value of zero

Instance includes:
src/core/contracts/libraries/DataStorage.sol:307

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USE A MORE RECENT VERSION OF SOLIDITY

Use a solidity version of at least 0.8.0 to get overflow protection without LowGasSafeMath Use a solidity version of at least 0.8.2 to get simple compiler automatic inlining Use a solidity version of at least 0.8.3 to get better struct packing and cheaper multiple storage reads Use a solidity version of at least 0.8.4 to get custom errors, which are cheaper at deployment than revert()/require() strings Use a solidity version of at least 0.8.10 to have external calls skip contract existence checks if the external call has a return value.

Instances include: src/core/contracts/AlgebraFactory.sol:2 src/core/contracts/AlgebraPool.sol:2 src/core/contracts/AlgebraPoolDeployer.sol:2 src/core/contracts/DataStorageOperator.sol:2 src/core/contracts/libraries/AdaptiveFee.sol:2 src/core/contracts/libraries/Constants.sol:2 src/core/contracts/libraries/DataStorage.sol:2 src/core/contracts/libraries/PriceMovementMath.sol:2 src/core/contracts/libraries/TickManager.sol:2 src/core/contracts/libraries/TickTable.sol:2 src/core/contracts/libraries/TokenDeltaMath.sol:2](https://github.com/code-423n4/2022-09-quickswap/blob/main/src/core/contracts/libraries/TokenDeltaMath.sol#L2) [src/core/contracts/base/PoolImmutables.sol:2](https://github.com/code-423n4/2022-09-quickswap/blob/main/src/core/contracts/base/PoolImmutables.sol#L2) [src/core/contracts/base/PoolState.sol:2`