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core, params: polish net gas metering PR a bit

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This commit is contained in:
Péter Szilágyi 2018-09-18 16:24:35 +03:00
parent caa2c23a38
commit 5d921fa3a0
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GPG Key ID: E9AE538CEDF8293D
11 changed files with 167 additions and 228 deletions
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63
core/state/state_object.go
View File

@ -77,9 +77,9 @@ type stateObject struct {
trie Trie // storage trie, which becomes non-nil on first access
code Code // contract bytecode, which gets set when code is loaded
cachedStorage Storage // Storage entry cache to avoid duplicate reads
originStorage Storage // Storage cache of original entries to dedup rewrites
dirtyStorage Storage // Storage entries that need to be flushed to disk
originalValue Storage // Map of original storage values, at the beginning of current call context
// Cache flags.
// When an object is marked suicided it will be delete from the trie
// during the "update" phase of the state transition.
@ -115,9 +115,8 @@ func newObject(db *StateDB, address common.Address, data Account) *stateObject {
address: address,
addrHash: crypto.Keccak256Hash(address[:]),
data: data,
cachedStorage: make(Storage),
originStorage: make(Storage),
dirtyStorage: make(Storage),
originalValue: make(Storage),
}
}
@ -160,13 +159,25 @@ func (c *stateObject) getTrie(db Database) Trie {
return c.trie
}
// GetState returns a value in account storage.
// GetState retrieves a value from the account storage trie.
func (self *stateObject) GetState(db Database, key common.Hash) common.Hash {
value, exists := self.cachedStorage[key]
if exists {
// If we have a dirty value for this state entry, return it
value, dirty := self.dirtyStorage[key]
if dirty {
return value
}
// Load from DB in case it is missing.
// Otherwise return the entry's original value
return self.GetCommittedState(db, key)
}
// GetCommittedState retrieves a value from the committed account storage trie.
func (self *stateObject) GetCommittedState(db Database, key common.Hash) common.Hash {
// If we have the original value cached, return that
value, cached := self.originStorage[key]
if cached {
return value
}
// Otherwise load the value from the database
enc, err := self.getTrie(db).TryGet(key[:])
if err != nil {
self.setError(err)
@ -179,37 +190,27 @@ func (self *stateObject) GetState(db Database, key common.Hash) common.Hash {
}
value.SetBytes(content)
}
self.cachedStorage[key] = value
self.originStorage[key] = value
return value
}
// GetOriginalStateValue returns the state value that is currently in the Trie, that is, ignoring any
// changes that have been made but not yet written to trie.
func (self *stateObject) GetOriginalStateValue(db Database, key common.Hash) common.Hash{
if original, exist:= self.originalValue[key]; exist {
// original value has been set, return it
return original
}
return self.GetState(db, key)
}
// SetState updates a value in account storage.
func (self *stateObject) SetState(db Database, key, value common.Hash) {
// If the new value is the same as old, don't set
prev := self.GetState(db, key)
if prev == value {
return
}
// New value is different, update and journal the change
self.db.journal.append(storageChange{
account: &self.address,
key: key,
prevalue: prev,
})
if _, isSet := self.originalValue[key]; !isSet {
// original value has not been set, so set it now
self.originalValue[key] = prev
}
self.setState(key, value)
}
func (self *stateObject) setState(key, value common.Hash) {
self.cachedStorage[key] = value
self.dirtyStorage[key] = value
}
@ -218,6 +219,13 @@ func (self *stateObject) updateTrie(db Database) Trie {
tr := self.getTrie(db)
for key, value := range self.dirtyStorage {
delete(self.dirtyStorage, key)
// Skip noop changes, persist actual changes
if value == self.originStorage[key] {
continue
}
self.originStorage[key] = value
if (value == common.Hash{}) {
self.setError(tr.TryDelete(key[:]))
continue
@ -226,10 +234,6 @@ func (self *stateObject) updateTrie(db Database) Trie {
v, _ := rlp.EncodeToBytes(bytes.TrimLeft(value[:], "\x00"))
self.setError(tr.TryUpdate(key[:], v))
}
// Clean the map containing 'original' value of storage entries
for k, _ := range self.originalValue {
delete(self.originalValue, k)
}
return tr
}
@ -299,8 +303,7 @@ func (self *stateObject) deepCopy(db *StateDB) *stateObject {
}
stateObject.code = self.code
stateObject.dirtyStorage = self.dirtyStorage.Copy()
stateObject.cachedStorage = self.dirtyStorage.Copy()
stateObject.originalValue = self.originalValue.Copy()
stateObject.originStorage = self.originStorage.Copy()
stateObject.suicided = self.suicided
stateObject.dirtyCode = self.dirtyCode
stateObject.deleted = self.deleted

58
core/state/state_test.go
View File

@ -96,11 +96,15 @@ func (s *StateSuite) TestNull(c *checker.C) {
s.state.CreateAccount(address)
//value := common.FromHex("0x823140710bf13990e4500136726d8b55")
var value common.Hash
s.state.SetState(address, common.Hash{}, value)
s.state.Commit(false)
value = s.state.GetState(address, common.Hash{})
if value != (common.Hash{}) {
c.Errorf("expected empty hash. got %x", value)
if value := s.state.GetState(address, common.Hash{}); value != (common.Hash{}) {
c.Errorf("expected empty current value, got %x", value)
}
if value := s.state.GetCommittedState(address, common.Hash{}); value != (common.Hash{}) {
c.Errorf("expected empty committed value, got %x", value)
}
}
@ -110,20 +114,24 @@ func (s *StateSuite) TestSnapshot(c *checker.C) {
data1 := common.BytesToHash([]byte{42})
data2 := common.BytesToHash([]byte{43})
// snapshot the genesis state
genesis := s.state.Snapshot()
// set initial state object value
s.state.SetState(stateobjaddr, storageaddr, data1)
// get snapshot of current state
snapshot := s.state.Snapshot()
// set new state object value
// set a new state object value, revert it and ensure correct content
s.state.SetState(stateobjaddr, storageaddr, data2)
// restore snapshot
s.state.RevertToSnapshot(snapshot)
// get state storage value
res := s.state.GetState(stateobjaddr, storageaddr)
c.Assert(s.state.GetState(stateobjaddr, storageaddr), checker.DeepEquals, data1)
c.Assert(s.state.GetCommittedState(stateobjaddr, storageaddr), checker.DeepEquals, common.Hash{})
c.Assert(data1, checker.DeepEquals, res)
// revert up to the genesis state and ensure correct content
s.state.RevertToSnapshot(genesis)
c.Assert(s.state.GetState(stateobjaddr, storageaddr), checker.DeepEquals, common.Hash{})
c.Assert(s.state.GetCommittedState(stateobjaddr, storageaddr), checker.DeepEquals, common.Hash{})
}
func (s *StateSuite) TestSnapshotEmpty(c *checker.C) {
@ -208,24 +216,30 @@ func compareStateObjects(so0, so1 *stateObject, t *testing.T) {
t.Fatalf("Code mismatch: have %v, want %v", so0.code, so1.code)
}
if len(so1.cachedStorage) != len(so0.cachedStorage) {
t.Errorf("Storage size mismatch: have %d, want %d", len(so1.cachedStorage), len(so0.cachedStorage))
if len(so1.dirtyStorage) != len(so0.dirtyStorage) {
t.Errorf("Dirty storage size mismatch: have %d, want %d", len(so1.dirtyStorage), len(so0.dirtyStorage))
}
for k, v := range so1.cachedStorage {
if so0.cachedStorage[k] != v {
t.Errorf("Storage key %x mismatch: have %v, want %v", k, so0.cachedStorage[k], v)
for k, v := range so1.dirtyStorage {
if so0.dirtyStorage[k] != v {
t.Errorf("Dirty storage key %x mismatch: have %v, want %v", k, so0.dirtyStorage[k], v)
}
}
for k, v := range so0.cachedStorage {
if so1.cachedStorage[k] != v {
t.Errorf("Storage key %x mismatch: have %v, want none.", k, v)
for k, v := range so0.dirtyStorage {
if so1.dirtyStorage[k] != v {
t.Errorf("Dirty storage key %x mismatch: have %v, want none.", k, v)
}
}
if so0.suicided != so1.suicided {
t.Fatalf("suicided mismatch: have %v, want %v", so0.suicided, so1.suicided)
if len(so1.originStorage) != len(so0.originStorage) {
t.Errorf("Origin storage size mismatch: have %d, want %d", len(so1.originStorage), len(so0.originStorage))
}
for k, v := range so1.originStorage {
if so0.originStorage[k] != v {
t.Errorf("Origin storage key %x mismatch: have %v, want %v", k, so0.originStorage[k], v)
}
}
for k, v := range so0.originStorage {
if so1.originStorage[k] != v {
t.Errorf("Origin storage key %x mismatch: have %v, want none.", k, v)
}
if so0.deleted != so1.deleted {
t.Fatalf("Deleted mismatch: have %v, want %v", so0.deleted, so1.deleted)
}
}

23
core/state/statedb.go
View File

@ -247,18 +247,20 @@ func (self *StateDB) GetCodeHash(addr common.Address) common.Hash {
return common.BytesToHash(stateObject.CodeHash())
}
func (self *StateDB) GetState(addr common.Address, bhash common.Hash) common.Hash {
// GetState retrieves a value from the given account's storage trie.
func (self *StateDB) GetState(addr common.Address, hash common.Hash) common.Hash {
stateObject := self.getStateObject(addr)
if stateObject != nil {
return stateObject.GetState(self.db, bhash)
return stateObject.GetState(self.db, hash)
}
return common.Hash{}
}
func (self *StateDB) GetStateOriginal(addr common.Address, bhash common.Hash) common.Hash {
// GetCommittedState retrieves a value from the given account's committed storage trie.
func (self *StateDB) GetCommittedState(addr common.Address, hash common.Hash) common.Hash {
stateObject := self.getStateObject(addr)
if stateObject != nil {
return stateObject.GetOriginalStateValue(self.db, bhash)
return stateObject.GetCommittedState(self.db, hash)
}
return common.Hash{}
}
@ -454,19 +456,14 @@ func (db *StateDB) ForEachStorage(addr common.Address, cb func(key, value common
if so == nil {
return
}
// When iterating over the storage check the cache first
for h, value := range so.cachedStorage {
cb(h, value)
}
it := trie.NewIterator(so.getTrie(db.db).NodeIterator(nil))
for it.Next() {
// ignore cached values
key := common.BytesToHash(db.trie.GetKey(it.Key))
if _, ok := so.cachedStorage[key]; !ok {
cb(key, common.BytesToHash(it.Value))
if value, dirty := so.dirtyStorage[key]; dirty {
cb(key, value)
continue
}
cb(key, common.BytesToHash(it.Value))
}
}

8
core/state/statedb_test.go
View File

@ -381,11 +381,11 @@ func (test *snapshotTest) checkEqual(state, checkstate *StateDB) error {
checkeq("GetCodeSize", state.GetCodeSize(addr), checkstate.GetCodeSize(addr))
// Check storage.
if obj := state.getStateObject(addr); obj != nil {
state.ForEachStorage(addr, func(key, val common.Hash) bool {
return checkeq("GetState("+key.Hex()+")", val, checkstate.GetState(addr, key))
state.ForEachStorage(addr, func(key, value common.Hash) bool {
return checkeq("GetState("+key.Hex()+")", checkstate.GetState(addr, key), value)
})
checkstate.ForEachStorage(addr, func(key, checkval common.Hash) bool {
return checkeq("GetState("+key.Hex()+")", state.GetState(addr, key), checkval)
checkstate.ForEachStorage(addr, func(key, value common.Hash) bool {
return checkeq("GetState("+key.Hex()+")", checkstate.GetState(addr, key), value)
})
}
if err != nil {

99
core/vm/gas_table.go
View File

@ -118,77 +118,68 @@ func gasReturnDataCopy(gt params.GasTable, evm *EVM, contract *Contract, stack *
func gasSStore(gt params.GasTable, evm *EVM, contract *Contract, stack *Stack, mem *Memory, memorySize uint64) (uint64, error) {
var (
y, x = stack.Back(1), stack.Back(0)
val = evm.StateDB.GetState(contract.Address(), common.BigToHash(x))
current = evm.StateDB.GetState(contract.Address(), common.BigToHash(x))
)
// This checks for 3 scenario's and calculates gas accordingly
// The legacy gas metering only takes into consideration the current state
if !evm.chainRules.IsConstantinople {
// This checks for 3 scenario's and calculates gas accordingly:
//
// 1. From a zero-value address to a non-zero value (NEW VALUE)
// 2. From a non-zero value address to a zero-value address (DELETE)
// 3. From a non-zero to a non-zero (CHANGE)
if val == (common.Hash{}) && y.Sign() != 0 {
// 0 => non 0
switch {
case current == (common.Hash{}) && y.Sign() != 0: // 0 => non 0
return params.SstoreSetGas, nil
} else if val != (common.Hash{}) && y.Sign() == 0 {
// non 0 => 0
case current != (common.Hash{}) && y.Sign() == 0: // non 0 => 0
evm.StateDB.AddRefund(params.SstoreRefundGas)
return params.SstoreClearGas, nil
} else {
// non 0 => non 0 (or 0 => 0)
default: // non 0 => non 0 (or 0 => 0)
return params.SstoreResetGas, nil
}
}
// gasSStoreEip1283 calculates SSTORE gas cost according to EIP-1283
func gasSStoreEip1283(gt params.GasTable, evm *EVM, contract *Contract, stack *Stack, mem *Memory, memorySize uint64) (uint64, error) {
var (
y, x = stack.Back(1), stack.Back(0)
current = evm.StateDB.GetState(contract.Address(), common.BigToHash(x))
)
//1. If current value equals new value (this is a no-op), 200 gas is deducted.
//2. If current value does not equal new value
// 2.1 If original value equals current value (this storage slot has not been changed by the current execution context)
// 2.1.1 If original value is 0, 20000 gas is deducted.
// 2.1.2 Otherwise, 5000 gas is deducted. If new value is 0, add 15000 gas to refund counter.
// 2.2 If original value does not equal current value (this storage slot is dirty), 200 gas is deducted. Apply both of the following clauses.
// 2.2.1 If original value is not 0
// 2.2.1.1 If current value is 0 (also means that new value is not 0), remove 15000 gas from refund counter. We can prove that refund counter will never go below 0.
// 2.2.1.2 If new value is 0 (also means that current value is not 0), add 15000 gas to refund counter.
// 2.2.2 If original value equals new value (this storage slot is reset)
// 2.2.2.1 If original value is 0, add 19800 gas to refund counter.
// 2.2.2.2 Otherwise, add 4800 gas to refund counter.
new := common.BigToHash(y)
if current == new {
// 1. current == new
return 200, nil
}
original := evm.StateDB.GetStateOriginal(contract.Address(), common.BigToHash(x))
// 2
if original == current { // 2.1
if original == (common.Hash{}) { // 2.1.1
return 20000, nil
// The new gas metering is based on net gas costs (EIP-1283):
//
// 1. If current value equals new value (this is a no-op), 200 gas is deducted.
// 2. If current value does not equal new value
// 2.1. If original value equals current value (this storage slot has not been changed by the current execution context)
// 2.1.1. If original value is 0, 20000 gas is deducted.
// 2.1.2. Otherwise, 5000 gas is deducted. If new value is 0, add 15000 gas to refund counter.
// 2.2. If original value does not equal current value (this storage slot is dirty), 200 gas is deducted. Apply both of the following clauses.
// 2.2.1. If original value is not 0
// 2.2.1.1. If current value is 0 (also means that new value is not 0), remove 15000 gas from refund counter. We can prove that refund counter will never go below 0.
// 2.2.1.2. If new value is 0 (also means that current value is not 0), add 15000 gas to refund counter.
// 2.2.2. If original value equals new value (this storage slot is reset)
// 2.2.2.1. If original value is 0, add 19800 gas to refund counter.
// 2.2.2.2. Otherwise, add 4800 gas to refund counter.
value := common.BigToHash(y)
if current == value { // noop (1)
return params.NetSstoreNoopGas, nil
}
// 2.1.2
if new == (common.Hash{}) {
evm.StateDB.AddRefund(15000)
original := evm.StateDB.GetCommittedState(contract.Address(), common.BigToHash(x))
if original == current {
if original == (common.Hash{}) { // create slot (2.1.1)
return params.NetSstoreInitGas, nil
}
return 5000, nil
if value == (common.Hash{}) { // delete slot (2.1.2b)
evm.StateDB.AddRefund(params.NetSstoreClearRefund)
}
// 2.2
if original != (common.Hash{}) { // 2.2.1
if current == (common.Hash{}) { // 2.2.1.1
evm.StateDB.SubRefund(15000)
} else {
// 2.2.1.2
evm.StateDB.AddRefund(15000)
return params.NetSstoreCleanGas, nil // write existing slot (2.1.2)
}
if original != (common.Hash{}) {
if current == (common.Hash{}) { // recreate slot (2.2.1.1)
evm.StateDB.SubRefund(params.NetSstoreClearRefund)
} else if value == (common.Hash{}) { // delete slot (2.2.1.2)
evm.StateDB.AddRefund(params.NetSstoreClearRefund)
}
}
if original == new { // 2.2.2
if original == (common.Hash{}) {
evm.StateDB.AddRefund(19800)
} else {
evm.StateDB.AddRefund(4800)
if original == value {
if original == (common.Hash{}) { // reset to original inexistent slot (2.2.2.1)
evm.StateDB.AddRefund(params.NetSstoreResetClearRefund)
} else { // reset to original existing slot (2.2.2.2)
evm.StateDB.AddRefund(params.NetSstoreResetRefund)
}
}
return 200, nil
return params.NetSstoreDirtyGas, nil
}
func makeGasLog(n uint64) gasFunc {

2
core/vm/interface.go
View File

@ -43,8 +43,8 @@ type StateDB interface {
SubRefund(uint64)
GetRefund() uint64
GetCommittedState(common.Address, common.Hash) common.Hash
GetState(common.Address, common.Hash) common.Hash
GetStateOriginal(common.Address, common.Hash) common.Hash
SetState(common.Address, common.Hash, common.Hash)
Suicide(common.Address) bool

8
core/vm/jump_table.go
View File

@ -95,14 +95,6 @@ func newConstantinopleInstructionSet() [256]operation {
writes: true,
returns: true,
}
instructionSet[SSTORE] = operation{
execute: opSstore,
gasCost: gasSStoreEip1283,
validateStack: makeStackFunc(2, 0),
valid: true,
writes: true,
}
return instructionSet
}

5
core/vm/logger_test.go
View File

@ -41,11 +41,6 @@ func (d *dummyContractRef) SetBalance(*big.Int) {}
func (d *dummyContractRef) SetNonce(uint64) {}
func (d *dummyContractRef) Balance() *big.Int { return new(big.Int) }
type dummyStateDB struct {
NoopStateDB
ref *dummyContractRef
}
func TestStoreCapture(t *testing.T) {
var (
env = NewEVM(Context{}, nil, params.TestChainConfig, Config{})

72
core/vm/noop.go
View File

@ -1,72 +0,0 @@
// Copyright 2016 The go-ethereum Authors
// This file is part of the go-ethereum library.
//
// The go-ethereum library is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// The go-ethereum library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
package vm
import (
"math/big"
"github.com/ethereum/go-ethereum/common"
"github.com/ethereum/go-ethereum/core/types"
)
func NoopCanTransfer(db StateDB, from common.Address, balance *big.Int) bool {
return true
}
func NoopTransfer(db StateDB, from, to common.Address, amount *big.Int) {}
type NoopEVMCallContext struct{}
func (NoopEVMCallContext) Call(caller ContractRef, addr common.Address, data []byte, gas, value *big.Int) ([]byte, error) {
return nil, nil
}
func (NoopEVMCallContext) CallCode(caller ContractRef, addr common.Address, data []byte, gas, value *big.Int) ([]byte, error) {
return nil, nil
}
func (NoopEVMCallContext) Create(caller ContractRef, data []byte, gas, value *big.Int) ([]byte, common.Address, error) {
return nil, common.Address{}, nil
}
func (NoopEVMCallContext) DelegateCall(me ContractRef, addr common.Address, data []byte, gas *big.Int) ([]byte, error) {
return nil, nil
}
type NoopStateDB struct{}
func (NoopStateDB) CreateAccount(common.Address) {}
func (NoopStateDB) SubBalance(common.Address, *big.Int) {}
func (NoopStateDB) AddBalance(common.Address, *big.Int) {}
func (NoopStateDB) GetBalance(common.Address) *big.Int { return nil }
func (NoopStateDB) GetNonce(common.Address) uint64 { return 0 }
func (NoopStateDB) SetNonce(common.Address, uint64) {}
func (NoopStateDB) GetCodeHash(common.Address) common.Hash { return common.Hash{} }
func (NoopStateDB) GetCode(common.Address) []byte { return nil }
func (NoopStateDB) SetCode(common.Address, []byte) {}
func (NoopStateDB) GetCodeSize(common.Address) int { return 0 }
func (NoopStateDB) AddRefund(uint64) {}
func (NoopStateDB) SubRefund(uint64) {}
func (NoopStateDB) GetRefund() uint64 { return 0 }
func (NoopStateDB) GetState(common.Address, common.Hash) common.Hash { return common.Hash{} }
func (NoopStateDB) GetStateOriginal(common.Address, common.Hash) common.Hash { return common.Hash{} }
func (NoopStateDB) SetState(common.Address, common.Hash, common.Hash) {}
func (NoopStateDB) Suicide(common.Address) bool { return false }
func (NoopStateDB) HasSuicided(common.Address) bool { return false }
func (NoopStateDB) Exist(common.Address) bool { return false }
func (NoopStateDB) Empty(common.Address) bool { return false }
func (NoopStateDB) RevertToSnapshot(int) {}
func (NoopStateDB) Snapshot() int { return 0 }
func (NoopStateDB) AddLog(*types.Log) {}
func (NoopStateDB) AddPreimage(common.Hash, []byte) {}
func (NoopStateDB) ForEachStorage(common.Address, func(common.Hash, common.Hash) bool) {}

12
params/config.go
View File

@ -335,7 +335,7 @@ func (err *ConfigCompatError) Error() string {
type Rules struct {
ChainID *big.Int
IsHomestead, IsEIP150, IsEIP155, IsEIP158 bool
IsByzantium bool
IsByzantium, IsConstantinople bool
}
// Rules ensures c's ChainID is not nil.
@ -344,5 +344,13 @@ func (c *ChainConfig) Rules(num *big.Int) Rules {
if chainID == nil {
chainID = new(big.Int)
}
return Rules{ChainID: new(big.Int).Set(chainID), IsHomestead: c.IsHomestead(num), IsEIP150: c.IsEIP150(num), IsEIP155: c.IsEIP155(num), IsEIP158: c.IsEIP158(num), IsByzantium: c.IsByzantium(num)}
return Rules{
ChainID: new(big.Int).Set(chainID),
IsHomestead: c.IsHomestead(num),
IsEIP150: c.IsEIP150(num),
IsEIP155: c.IsEIP155(num),
IsEIP158: c.IsEIP158(num),
IsByzantium: c.IsByzantium(num),
IsConstantinople: c.IsConstantinople(num),
}
}

13
params/protocol_params.go
View File

@ -32,15 +32,26 @@ const (
TxGasContractCreation uint64 = 53000 // Per transaction that creates a contract. NOTE: Not payable on data of calls between transactions.
TxDataZeroGas uint64 = 4 // Per byte of data attached to a transaction that equals zero. NOTE: Not payable on data of calls between transactions.
QuadCoeffDiv uint64 = 512 // Divisor for the quadratic particle of the memory cost equation.
SstoreSetGas uint64 = 20000 // Once per SLOAD operation.
LogDataGas uint64 = 8 // Per byte in a LOG* operation's data.
CallStipend uint64 = 2300 // Free gas given at beginning of call.
Sha3Gas uint64 = 30 // Once per SHA3 operation.
Sha3WordGas uint64 = 6 // Once per word of the SHA3 operation's data.
SstoreSetGas uint64 = 20000 // Once per SLOAD operation.
SstoreResetGas uint64 = 5000 // Once per SSTORE operation if the zeroness changes from zero.
SstoreClearGas uint64 = 5000 // Once per SSTORE operation if the zeroness doesn't change.
SstoreRefundGas uint64 = 15000 // Once per SSTORE operation if the zeroness changes to zero.
NetSstoreNoopGas uint64 = 200 // Once per SSTORE operation if the value doesn't change.
NetSstoreInitGas uint64 = 20000 // Once per SSTORE operation from clean zero.
NetSstoreCleanGas uint64 = 5000 // Once per SSTORE operation from clean non-zero.
NetSstoreDirtyGas uint64 = 200 // Once per SSTORE operation from dirty.
NetSstoreClearRefund uint64 = 15000 // Once per SSTORE operation for clearing an originally existing storage slot
NetSstoreResetRefund uint64 = 4800 // Once per SSTORE operation for resetting to the original non-zero value
NetSstoreResetClearRefund uint64 = 19800 // Once per SSTORE operation for resetting to the original zero value
JumpdestGas uint64 = 1 // Refunded gas, once per SSTORE operation if the zeroness changes to zero.
EpochDuration uint64 = 30000 // Duration between proof-of-work epochs.
CallGas uint64 = 40 // Once per CALL operation & message call transaction.