Ecosyste.ms: Awesome
An open API service indexing awesome lists of open source software.
https://github.com/WTFAcademy/WTF-gas-optimization
WTF Solidity gas optimization techniques, verified with Foundry.
https://github.com/WTFAcademy/WTF-gas-optimization
blockchain dapp ethereum smart-contracts solidity web3
Last synced: about 2 months ago
JSON representation
WTF Solidity gas optimization techniques, verified with Foundry.
- Host: GitHub
- URL: https://github.com/WTFAcademy/WTF-gas-optimization
- Owner: WTFAcademy
- Created: 2023-03-15T06:45:59.000Z (over 1 year ago)
- Default Branch: main
- Last Pushed: 2024-05-21T08:41:27.000Z (4 months ago)
- Last Synced: 2024-07-29T03:33:15.101Z (about 2 months ago)
- Topics: blockchain, dapp, ethereum, smart-contracts, solidity, web3
- Language: Solidity
- Homepage:
- Size: 135 KB
- Stars: 201
- Watchers: 5
- Forks: 38
- Open Issues: 0
-
Metadata Files:
- Readme: README.md
Awesome Lists containing this project
- DeFi-Developer-Road-Map - WTF Gas Optimisation
README
# WTF Gas Optimization
Solidity gas optimization techniques, verified with Foundry.
总结 Solidity 智能合约省 gas 技巧，并使用 Foundry 验证。
Lead by [@0xKaso](https://github.com/0xKaso)
## Outline
[1. use constant and immutable](#1-use-constant-and-immutable)
[2. use calldata over memory](#2-use-calldata-over-memory)
[3. use Bitmap](#3-use-bitmap)
[4. use unchecked](#4-use-unchecked)
[5. use uint256 over uint8](#5-use-uint256-over-uint8)
[6. use custom error over require/assert](#6-use-custom-error-over-requireassert)
[7. use local variable over storage](#7-use-local-variable-over-storage)
[8. use clone over new/create2 to deploy contracts](#8-use-clone-over-newcreate2-to-deploy-contract)
[9. packing storage slots](#9-packing-storage-slots)
[10. use ++i as better increment](#10-use-i-as-better-increment)
[11. use uint in reentrancy guard](#11-use-uint-in-reentrancy-guard)
[12. use < over <=](#12-use--over)
[13. optimized selector/method id](#13-optimized-selector)
[14. selector/method-id order matters](#14-selector-order)
[15. use shorter string in require()](#15-shorter-string-in-require)
[16. use short circuit in logic operation `||` or `&&`](#16-short-circuit-in-logic-operation)
[17. delete variables to get gas refund](#17-delete-variables-to-get-gas-refund)
[18. do not initialize state variables with default values](#18-do-not-initialize-state-variables-with-default-values)
[19. swap 2 variables in 1 line with destructuring assignment](#19-swap-2-variables-in-1-line-with-destructuring-assignment)
[20. set constructor to payable to save gas](#20-set-constructor-to-payable-to-save-gas)
[21. use bytes32 for short string](#21-use-bytes32-for-short-string)
[22. use fixed-size array over dynamic array](#22-use-fixed-size-array-over-dynamic-array)
[23. use event to store data when possible](#23-use-event-to-store-data-when-possible)
[24. use `mapping` over `array` when possible](#24-use-mapping-over-array-when-possible)
## 1. use constant and immutable
[Code](https://github.com/WTFAcademy/WTF-gas-optimization/blob/main/01_Constant/Constant.sol) | [文章](https://github.com/WTFAcademy/WTF-gas-optimization/blob/main/01_Constant/readme.md)
**Testing**
```
forge test --contracts 01_Constant/Constant.t.sol --gas-report
```
**Gas report**
| Function Name | Gas Cost |
| ---------------- | -------- |
| varConstant | 161 ✅ |
| **varImmutable** | 161 ✅ |
| variable | 2261 |
## 2. use calldata over memory
[Code](https://github.com/WTFAcademy/WTF-gas-optimization/blob/main/02_CalldataAndMemory/CalldataAndMemory.sol) | [文章](https://github.com/WTFAcademy/WTF-gas-optimization/tree/main/02_CalldataAndMemory/readme.md)
**Testing**
```
forge test --contracts 02_CalldataAndMemory/CalldataAndMemory.T.sol --gas-report
```
**Gas report**
| Function Name | Gas Cost |
| ------------------- | -------- |
| **writeByCalldata** | 67905 ✅ |
| writeByMemory | 68456 |
## 3. use Bitmap
[Code](https://github.com/WTFAcademy/WTF-gas-optimization/blob/main/03_Bitmap/Bitmap.sol) | [文章](https://github.com/WTFAcademy/WTF-gas-optimization/blob/main/03_Bitmap/readme.md)
**Testing**
```
forge test --contracts 03_Bitmap/Bitmap.T.sol --gas-report
```
**Gas report**
| Function Name | Gas Cost |
| --------------------- | -------- |
| **setDataWithBitmap** | 22366 ✅ |
| setDataWithBoolArray | 35729 |
## 4. use unchecked
[Code](https://github.com/WTFAcademy/WTF-gas-optimization/blob/main/04_Unchecked/Unchecked.sol) | [文章](https://github.com/WTFAcademy/WTF-gas-optimization/blob/main/04_Unchecked/readme.md)
**Testing**
```
forge test --contracts 04_unchecked/Unchecked.T.sol --gas-report
```
**Gas report**
| Function Name | Gas Cost |
| ---------------- | --------- |
| forNormal | 1910309 |
| **forUnckecked** | 570287 ✅ |
## 5. use uint256 over uint8
[Code](https://github.com/WTFAcademy/WTF-gas-optimization/blob/main/05_Uint/Uint.sol) | [文章](https://github.com/WTFAcademy/WTF-gas-optimization/blob/main/05_Uint/readme.md)
**Testing**
```
forge test --contracts 05_Uint/Uint.T.sol --gas-report
```
**Gas report**
| Function Name | Gas Cost |
| ---------------- | -------- |
| read Uint8 | 2301 |
| read Uint32 | 2301 |
| **read Uint256** | 2261 ✅ |
| set Uint8 | 22234 |
| set Uint128 | 22234 |
| **set Uint256** | 22238 |
| UseUint8 | 53,427 |
| UseUint32 | 53,895 |
| **UseUint256** | 42,950 ✅ |
## 6. use custom error over require/assert
[Code](https://github.com/WTFAcademy/WTF-gas-optimization/blob/main/06_Error/Error.sol) | [文章](https://github.com/WTFAcademy/WTF-gas-optimization/blob/main/06_Error/readme.md)
**Testing**
```
forge test --contracts 06_Error/Error.T.sol --gas-report
```
**Gas report**
| Error Name | Gas Cost |
| ---------- | -------- |
| Assert | 180 |
| Require | 268 |
| **Revert** | 164 ✅ |
## 7. use local variable over storage
[Code](https://github.com/WTFAcademy/WTF-gas-optimization/blob/main/07_LocalData/LocalData.sol) | [文章](https://github.com/WTFAcademy/WTF-gas-optimization/blob/main/07_LocalData/readme.md)
**Testing**
```bash
forge test --contracts 07_LocalData/LocalData.T.sol --gas-report
```
**Gas report**
| Data Type | Gas Cost |
| ------------- | ---------- |
| **localData** | 1902339 ✅ |
| storageData | 4022155 |
## 8. use clone over new/create2 to deploy contract
[Code](https://github.com/WTFAcademy/WTF-gas-optimization/blob/main/08_Clone/Clone.sol) | [文章](https://github.com/WTFAcademy/WTF-gas-optimization/blob/main/08_Clone/readme.md)
**Testing**
```bash
forge test --contracts 08_Clone/Clone.T.sol --gas-report
```
**Gas report**
| Create Type | Gas Cost |
| ----------- | -------- |
| **clone** | 41493 ✅ |
| create2 | 93031 |
| new | 79515 |
## 9. packing storage slots
[Code](https://github.com/WTFAcademy/WTF-gas-optimization/blob/main/09_Packing/Packing.sol) | [文章](https://github.com/WTFAcademy/WTF-gas-optimization/blob/main/09_Packing/readme.md)
**Testing**
```bash
forge test --contracts 09_Packing/Packing.T.sol --gas-report
```
**Gas report**
| Create Type | Gas Cost |
| ----------- | --------- |
| normal | 133521 |
| **packing** | 111351 ✅ |
## 10. use ++i as better increment
[Code](https://github.com/WTFAcademy/WTF-gas-optimization/blob/main/10_Increment/Increment.sol) | [文章](https://github.com/WTFAcademy/WTF-gas-optimization/blob/main/10_Increment/readme.md)
```bash
forge test --contracts 10_Increment/Increment.T.sol --gas-report
```
**Gas report**
| Increment | Gas Cost |
| --------- | -------- |
| i += 1 | 204 |
| i = i +1 | 204 |
| i++ | 198 |
| ++i | 193 ✅ |
## 11. use Uint in Reentrancy Guard
[Code](https://github.com/WTFAcademy/WTF-gas-optimization/blob/main/11_ReentrancyGuard/ReentrancyGuard.sol) | [文章](https://github.com/WTFAcademy/WTF-gas-optimization/blob/main/11_ReentrancyGuard/readme.md)
**Testing**
```bash
forge test --contracts 11_ReentrancyGuard/ReentrancyGuard.T.sol --gas-report
```
**Gas report**
| ReentrancyGuard | Gas Cost | tips |
| -----------------| -------- | ----------------------------------|
| Bool | 27757 | |
| Uint01 | 27604 | 0 to non-zero -> 20000 gas |
| **Uint12** | 13908 ✅ | non-zero to non-zero -> 2900 gas |
## 12. use < over <=
[Code](https://github.com/WTFAcademy/WTF-gas-optimization/blob/main/12_LessThan/LessThan.sol) | [文章](https://github.com/WTFAcademy/WTF-gas-optimization/blob/main/12_LessThan/readme.md)
**Testing**
```bash
forge test --contracts 12_LessThan/LessThan.t.sol --gas-report
```
**Gas report**
| Operator | Gas Cost |
| ---------------- | -------- |
| <= | 250 |
| <| 247 ✅ |
## 13 optimized selector
[Code](https://github.com/WTFAcademy/WTF-gas-optimization/blob/main/13_MethodName/MethodName.sol) | [文章](https://github.com/WTFAcademy/WTF-gas-optimization/blob/main/13_MethodName/readme.md)
**Testing**
```bash
forge test --contracts 13_MethodName/MethodName.t.sol --gas-report
```
**Gas report**
| Operator | Gas Cost |
| ---------------- | -------- |
| regular selector 0xf8a8fd6d | 5285 |
| optimized selector 0x000073eb | 5265 ✅ |
## 14 selector order
[Code](https://github.com/WTFAcademy/WTF-gas-optimization/blob/main/14_MethodIdSort) | [文章](https://github.com/WTFAcademy/WTF-gas-optimization/blob/main/14_MethodIdSort/readme.md)
**Testing**
```bash
forge test --contracts 14_MethodIdSort/MethodIdSort.t.sol --gas-report
```
**Gas report**
| Operator | Gas Cost |
| -------- | -------- |
| test1 0x0dbe671f | 164 |
| test2 0x66e41cb7 | 142 |
| test3 0x0a8e8e01 | 120 |
| test_y2K 0x000073eb | 98 ✅ |
## 15 shorter string in require()
[Code](https://github.com/WTFAcademy/WTF-gas-optimization/blob/main/15_RequireString/RequireString.sol)｜[文章](https://github.com/WTFAcademy/WTF-gas-optimization/blob/main/15_RequireString)
**Testing**
```bash
forge test --contracts 15_RequireString/RequireString.t.sol --gas-report
```
**Gas report**
| Operator | Gas Cost |
| -------- | -------- |
| longString | 2578 |
| shortString | 2347 ✅ |
## 16. short circuit in logic operation
[Code](https://github.com/WTFAcademy/WTF-gas-optimization/blob/main/16_ShortCircuit/ShortCircuit.sol) | [文章](https://github.com/WTFAcademy/WTF-gas-optimization/blob/main/16_ShortCircuit/readme.md)
**Testing**
```bash
forge test --contracts 16_ShortCircuit/ShortCircuit.t.sol --gas-report
```
**Gas report**
| Operator | Gas Cost |
| -------- | -------- |
| normal | 191,282 |
| shortCircuit | 120 ✅ |
## 17. delete variables to get gas refund
[Code](https://github.com/WTFAcademy/WTF-gas-optimization/blob/main/17_DeleteVar/DeleteVar.sol) | [文章](https://github.com/WTFAcademy/WTF-gas-optimization/blob/main/17_DeleteVar/readme.md)
**Testing**
```bash
forge test --contracts 17_DeleteVar/DeleteVar.t.sol --gas-report
```
**Gas report**
| Operator | Gas Cost |
| -------- | -------- |
| update | 22,238 |
| updateDefault | 2360 ✅ |
| updateDelete | 2316 ✅ |
## 18. do not initialize state variables with default values
[Code](https://github.com/WTFAcademy/WTF-gas-optimization/blob/main/18_InitDefault)
**Testing**
```bash
forge test --contracts 18_InitDefault/InitDefault.t.sol --gas-report
```
**Gas report**
| Operator | Gas Cost |
| -------- | -------- |
| testDefault | 67,148 ✅ |
| testInitDefault | 69,376 |
## 19. swap 2 variables in 1 line with destructuring assignment
[Code](https://github.com/WTFAcademy/WTF-gas-optimization/blob/main/19_SwapVars)
**Testing**
```bash
forge test --contracts 19_SwapVars/SwapVars.t.sol --gas-report
```
**Gas report**
**This technique will not save gas, but it makes your code look better :p**
| Operator | Gas Cost |
| -------- | -------- |
| swap | 282 |
| desSwap | 282 ✅ |
## 20. set constructor to payable to save gas
You can cut out 10 opcodes in the creation-time EVM bytecode if you declare a constructor payable. The following opcodes are cut out:
- `CALLVALUE`
- `DUP1`
- `ISZERO`
- `PUSH2`
- `JUMPI`
- `PUSH1`
- `DUP1`
- `REVERT`
- `JUMPDEST`
- `POP`
In Solidity, this chunk of assembly would mean the following:
```solidity
if(msg.value != 0) revert();
```
[Code](https://github.com/WTFAcademy/WTF-gas-optimization/blob/main/20_PayableConstructor)
**Testing**
```bash
forge test --contracts 20_PayableConstructor/PayableConstructor.t.sol --gas-report
```
**Gas report**
| Operator | Gas Cost |
| -------- | -------- |
| default | 67,171 |
| payable constructor | 67,102 ✅ |
## 21. use bytes32 for short string
[Code](https://github.com/WTFAcademy/WTF-gas-optimization/blob/main/21_Bytes32String)
**Testing**
```bash
forge test --contracts 21_Bytes32String/Bytes32String.t.sol --gas-report
```
**Gas report**
| Operator | Gas Cost |
| -------- | -------- |
| setBytes32 | 22,222 ✅ |
| setString | 22,682 |
## 22. use fixed-size array over dynamic array
[Code](https://github.com/WTFAcademy/WTF-gas-optimization/blob/main/22_FixedSize)
**Testing**
```bash
forge test --contracts 22_FixedSize/FixedSize.t.sol --gas-report
```
**Gas report**
| Operator | Gas Cost |
| -------- | -------- |
| set dynamic-length array | 2,224,770 |
| set fixed-length array | 2,182,608 ✅ |
## 23. use `event` to store data when possible
[Code](https://github.com/WTFAcademy/WTF-gas-optimization/blob/main/23_Event)
**Testing**
```bash
forge test --contracts 23_Event/Event.t.sol --gas-report
```
**Gas report**
| Operator | Gas Cost |
| -------- | -------- |
| useVar | 22,216 |
| useEvent | 1,189 ✅ |
## 24. use `mapping` over `array` when possible
[Code](https://github.com/WTFAcademy/WTF-gas-optimization/blob/main/24_MappingArray)
**Testing**
```bash
forge test --contracts 24_MappingArray/MappingArray.t.sol --gas-report
```
**Gas report**
| Operator | Gas Cost |
| -------- | -------- |
| Mapping get | 451 ✅ |
| Mapping insert | 22,385 ✅ |
| Mapping remove | 305 ✅ |
| Array get | 710 |
| Array insert | 44,442 |
| Array remove | 748 |
## WTF Gas Optimization 贡献者
贡献者是WTF学院的基石
## Reference
1. [Solidity-Gas-Optimization-Tips](https://github.com/devanshbatham/Solidity-Gas-Optimization-Tips)