Gas Calculation Reference¶

Summary¶

Gas calculation in Fukuii is fully compliant with Ethereum specifications including EIP-2929 cold/warm storage access costs.

Status: ✅ Verified and compliant with ethereum/tests

EIP-2929 Gas Costs¶

EIP-2929 introduced cold/warm storage access costs for Berlin and later forks:

Operation	Cold Access	Warm Access
SLOAD	2,100 gas	100 gas
SSTORE (0 → non-zero)	22,100 gas	20,000 gas
SSTORE (non-zero → different)	5,000 gas	2,900 gas

Implementation Details¶

The gas calculation correctly handles: - G_cold_sload: 2,100 gas (first access to storage slot) - G_warm_storage_read: 100 gas (subsequent accesses) - G_sset: 20,000 gas (setting fresh slot) - G_sreset: 2,900 gas (resetting existing slot)

Example Calculation¶

For a simple contract that stores a value:

Contract Code: 0x600160010160005500
- PUSH1 0x01: 3 gas
- PUSH1 0x01: 3 gas
- ADD: 3 gas
- PUSH1 0x00: 3 gas
- SSTORE (cold): 20,000 (G_sset) + 2,100 (G_cold_sload) = 22,100 gas
- STOP: 0 gas
Transaction intrinsic: 21,000 gas
Total: 21,000 + 3 + 3 + 3 + 3 + 22,100 = 43,112 gas

Fork Configuration¶

Proper fork detection requires all fork block numbers to be configured. The implementation includes correct configurations for:

Fork	Key Parameters
Frontier	Base gas costs
Homestead	EIP-2/7
EIP-150	Gas repricing
EIP-155/160	Replay protection
Byzantium	EIP-658
Constantinople	EIP-1014, 1052, 1283
Petersburg	EIP-1283 removed
Istanbul	EIP-1884, 2028, 2200
Berlin	EIP-2929 cold/warm
London	EIP-3529 (ETC partial)

Fork Detection Logic¶

def ethForkForBlockNumber(blockNumber: BigInt): EthForks.Value = blockNumber match {
  case _ if blockNumber < byzantiumBlockNumber      => BeforeByzantium
  case _ if blockNumber < constantinopleBlockNumber => Byzantium
  case _ if blockNumber < petersburgBlockNumber     => Constantinople
  case _ if blockNumber < istanbulBlockNumber       => Petersburg
  case _ if blockNumber < berlinBlockNumber         => Istanbul
  case _ if blockNumber >= berlinBlockNumber        => Berlin
}

Verification¶

Gas calculations have been verified against: - ✅ ethereum/tests official test suite - ✅ Core-geth reference implementation - ✅ Besu reference implementation

Key Files¶

src/main/scala/com/chipprbots/ethereum/vm/EvmConfig.scala - Gas schedule
src/main/scala/com/chipprbots/ethereum/vm/OpCode.scala - SSTORE gas logic
src/it/scala/com/chipprbots/ethereum/ethtest/TestConverter.scala - Fork configuration

References¶

Last Updated: November 2025
Status: ✅ Verified and compliant