#1 Use Calldata instead memory
https://github.com/Plex-Engineer/manifest-v2/blob/f6ebfe679973edf4f64832e64480ff5250ef8486/contracts/Proposal-Store.sol#L35
https://github.com/Plex-Engineer/manifest-v2/blob/f6ebfe679973edf4f64832e64480ff5250ef8486/contracts/Proposal-Store.sol#L42
https://github.com/Plex-Engineer/lending-market-v2/blob/443a8c0fed3c5018e95f3881a31b81a555c42b2d/contracts/Stableswap/BaseV1-periphery.sol#L150
https://github.com/Plex-Engineer/lending-market-v2/blob/443a8c0fed3c5018e95f3881a31b81a555c42b2d/contracts/Stableswap/BaseV1-periphery.sol#L379
In the external functions where the function argument is read-only, the function() has an inputed parameter that using memory, if this function didnt change the parameter, its cheaper to use calldata then memory. so we suggest to change it.
#2 Use Storage instead memory
https://github.com/Plex-Engineer/lending-market-v2/blob/443a8c0fed3c5018e95f3881a31b81a555c42b2d/contracts/Stableswap/BaseV1-core.sol#L222
https://github.com/Plex-Engineer/manifest-v2/blob/f6ebfe679973edf4f64832e64480ff5250ef8486/contracts/Proposal-Store.sol#L38
https://github.com/Plex-Engineer/manifest-v2/blob/f6ebfe679973edf4f64832e64480ff5250ef8486/contracts/Proposal-Store.sol#L45
https://github.com/Plex-Engineer/lending-market-v2/blob/443a8c0fed3c5018e95f3881a31b81a555c42b2d/contracts/Stableswap/BaseV1-core.sol#L164
https://github.com/Plex-Engineer/lending-market-v2/blob/443a8c0fed3c5018e95f3881a31b81a555c42b2d/contracts/Stableswap/BaseV1-core.sol#L193
https://github.com/Plex-Engineer/lending-market-v2/blob/443a8c0fed3c5018e95f3881a31b81a555c42b2d/contracts/Stableswap/BaseV1-core.sol#L208
https://github.com/Plex-Engineer/lending-market-v2/blob/443a8c0fed3c5018e95f3881a31b81a555c42b2d/contracts/Governance/GovernorBravoDelegate.sol#L39
https://github.com/Plex-Engineer/lending-market-v2/blob/443a8c0fed3c5018e95f3881a31b81a555c42b2d/contracts/Accountant/AccountantDelegator.sol#L54
https://github.com/Plex-Engineer/lending-market-v2/blob/443a8c0fed3c5018e95f3881a31b81a555c42b2d/contracts/Accountant/AccountantDelegator.sol#L63
Use storage instead of memory to reduce the gas fee. i suggest change from
uint[] memory _prices = new uint[](points);
to
uint[] storage _prices = new uint[](points);
#3 Visibility
https://github.com/Plex-Engineer/lending-market-v2/blob/443a8c0fed3c5018e95f3881a31b81a555c42b2d/contracts/Stableswap/BaseV1-core.sol#L43
https://github.com/Plex-Engineer/lending-market-v2/blob/443a8c0fed3c5018e95f3881a31b81a555c42b2d/contracts/Governance/GovernorBravoDelegate.sol#L8-L18
https://github.com/Plex-Engineer/lending-market-v2/blob/443a8c0fed3c5018e95f3881a31b81a555c42b2d/contracts/NoteInterest.sol#L20-L23
change visibility from public to private or internal can save gas. so i recommend to change it.
#4 Default value
https://github.com/Plex-Engineer/lending-market-v2/blob/443a8c0fed3c5018e95f3881a31b81a555c42b2d/contracts/Stableswap/BaseV1-core.sol#L48
https://github.com/Plex-Engineer/lending-market-v2/blob/443a8c0fed3c5018e95f3881a31b81a555c42b2d/contracts/Stableswap/BaseV1-core.sol#L72
https://github.com/Plex-Engineer/lending-market-v2/blob/443a8c0fed3c5018e95f3881a31b81a555c42b2d/contracts/Stableswap/BaseV1-core.sol#L226-L227
https://github.com/Plex-Engineer/lending-market-v2/blob/443a8c0fed3c5018e95f3881a31b81a555c42b2d/contracts/Governance/GovernorBravoDelegate.sol#L88
the default value of uint is 0, so remove unnecassary explicit code initializations for default values e.g uint i = 0; to uint i;.
#5 Struct the mapping
https://github.com/Plex-Engineer/lending-market-v2/blob/443a8c0fed3c5018e95f3881a31b81a555c42b2d/contracts/Stableswap/BaseV1-core.sol#L51
struct the mapping (address=>uint) can reduce the gas fee.
#6 mload cheaper than sload.
https://github.com/Plex-Engineer/lending-market-v2/blob/443a8c0fed3c5018e95f3881a31b81a555c42b2d/contracts/Stableswap/BaseV1-core.sol#L172
Sload are more expensive then Mload and Mstore. Using Mload can reduce the gas fee.
so i suggest to change from
reserve0 = balance0;
reserve1 = balance1;
blockTimestampLast = blockTimestamp;
emit Sync(reserve0, reserve1);
to
reserve0 = balance0;
reserve1 = balance1;
blockTimestampLast = blockTimestamp;
emit Sync(balance0, balance1);
#7 Looping (Aritmathic)
https://github.com/Plex-Engineer/lending-market-v2/blob/443a8c0fed3c5018e95f3881a31b81a555c42b2d/contracts/Stableswap/BaseV1-core.sol#L210
default uint is 0 so remove unnecassary explicit can reduce gas.
caching the array length can reduce gas it caused access to a local variable is more cheap than query storage / calldata / memory in solidity.
pre increment e.g ++i more cheaper gas than post increment e.g i++. i suggest to use pre increment.
#8 use += (operation) instead =
https://github.com/Plex-Engineer/lending-market-v2/blob/443a8c0fed3c5018e95f3881a31b81a555c42b2d/contracts/Stableswap/BaseV1-core.sol#L235
change from
index = index + 1;
to
index =+ 1;
it can reduce gas fee.
#9 cache the routes.ength
https://github.com/Plex-Engineer/lending-market-v2/blob/443a8c0fed3c5018e95f3881a31b81a555c42b2d/contracts/Stableswap/BaseV1-periphery.sol#L379
caching routes.length to memory because use multiple times can reduce the gas.
#10 Use !=0 instead of >0
https://github.com/Plex-Engineer/lending-market-v2/blob/443a8c0fed3c5018e95f3881a31b81a555c42b2d/contracts/Stableswap/BaseV1-core.sol#L275
https://github.com/Plex-Engineer/lending-market-v2/blob/443a8c0fed3c5018e95f3881a31b81a555c42b2d/contracts/Stableswap/BaseV1-core.sol#L256
https://github.com/Plex-Engineer/lending-market-v2/blob/443a8c0fed3c5018e95f3881a31b81a555c42b2d/contracts/Stableswap/BaseV1-core.sol#L289
https://github.com/Plex-Engineer/lending-market-v2/blob/443a8c0fed3c5018e95f3881a31b81a555c42b2d/contracts/Stableswap/BaseV1-core.sol#L306
for unsigned integer, >0 is less efficient then !=0, so use !=0 instead of >0.
apply to others.
#11 short error message
https://github.com/Plex-Engineer/lending-market-v2/blob/443a8c0fed3c5018e95f3881a31b81a555c42b2d/contracts/Governance/GovernorBravoDelegate.sol#L158
https://github.com/Plex-Engineer/lending-market-v2/blob/443a8c0fed3c5018e95f3881a31b81a555c42b2d/contracts/Governance/GovernorBravoDelegate.sol#L140
https://github.com/Plex-Engineer/lending-market-v2/blob/443a8c0fed3c5018e95f3881a31b81a555c42b2d/contracts/Governance/GovernorBravoDelegate.sol#L129
https://github.com/Plex-Engineer/lending-market-v2/blob/443a8c0fed3c5018e95f3881a31b81a555c42b2d/contracts/Stableswap/BaseV1-periphery.sol#L420
https://github.com/Plex-Engineer/lending-market-v2/blob/443a8c0fed3c5018e95f3881a31b81a555c42b2d/contracts/Stableswap/BaseV1-periphery.sol#L123
https://github.com/Plex-Engineer/lending-market-v2/blob/443a8c0fed3c5018e95f3881a31b81a555c42b2d/contracts/Stableswap/BaseV1-periphery.sol#L122
https://github.com/Plex-Engineer/lending-market-v2/blob/443a8c0fed3c5018e95f3881a31b81a555c42b2d/contracts/Stableswap/BaseV1-periphery.sol#L104
https://github.com/Plex-Engineer/lending-market-v2/blob/443a8c0fed3c5018e95f3881a31b81a555c42b2d/contracts/Stableswap/BaseV1-periphery.sol#L241
https://github.com/Plex-Engineer/lending-market-v2/blob/443a8c0fed3c5018e95f3881a31b81a555c42b2d/contracts/Stableswap/BaseV1-periphery.sol#L246
https://github.com/Plex-Engineer/lending-market-v2/blob/443a8c0fed3c5018e95f3881a31b81a555c42b2d/contracts/WETH.sol#L29
https://github.com/Plex-Engineer/lending-market-v2/blob/443a8c0fed3c5018e95f3881a31b81a555c42b2d/contracts/WETH.sol#L72
https://github.com/Plex-Engineer/lending-market-v2/blob/443a8c0fed3c5018e95f3881a31b81a555c42b2d/contracts/WETH.sol#L89-L90
https://github.com/Plex-Engineer/lending-market-v2/blob/443a8c0fed3c5018e95f3881a31b81a555c42b2d/contracts/Accountant/AccountantDelegator.sol#L123
https://github.com/Plex-Engineer/lending-market-v2/blob/443a8c0fed3c5018e95f3881a31b81a555c42b2d/contracts/Treasury/TreasuryDelegator.sol#L31-L32
reduce string size of error message to bytes 32 can reduce the gas fee. reduce these if possible.
#12 Cache the routes.length
https://github.com/Plex-Engineer/lending-market-v2/blob/443a8c0fed3c5018e95f3881a31b81a555c42b2d/contracts/Stableswap/BaseV1-periphery.sol#L151
caching routes.length to memory because use multiple times can reduce the gas.
#13 Caching the unigovProposal.targets.length
https://github.com/Plex-Engineer/lending-market-v2/blob/443a8c0fed3c5018e95f3881a31b81a555c42b2d/contracts/Governance/GovernorBravoDelegate.sol#L42
caching unigovProposal.targets.length to memory because use multiple times can reduce the gas.
#14 use require instead &&
https://github.com/Plex-Engineer/lending-market/blob/755424c1f9ab3f9f0408443e6606f94e4f08a990/contracts/Governance/GovernorBravoDelegate.sol#L42-L45
use require instead of && for efficient gas cost. change it from
require(unigovProposal.targets.length == unigovProposal.values.length &&
unigovProposal.targets.length == unigovProposal.signatures.length &&
unigovProposal.targets.length == unigovProposal.calldatas.length,
"GovernorBravo::propose: proposal function information arity mismatch");
to
require(unigovProposal.targets.length == unigovProposal.values.length, "GovernorBravo::propose:
proposal function information arity mismatch");
require(unigovProposal.targets.length == unigovProposal.signatures.length, "GovernorBravo::propose:
proposal function information arity mismatch");
require(unigovProposal.targets.length == unigovProposal.calldatas.length, "GovernorBravo::propose:
proposal function information arity mismatch");