core/vm: use uint256 in EVM implementation (#20787)

* core/vm: use fixed uint256 library instead of big

* core/vm: remove intpools

* core/vm: upgrade uint256, fixes uint256.NewFromBig

* core/vm: use uint256.Int by value in Stack

* core/vm: upgrade uint256 to v1.0.0

* core/vm: don't preallocate space for 1024 stack items (only 16)

Co-authored-by: Martin Holst Swende <martin@swende.se>

Author: chfast

Diff for: core/vm/common.go

@@ -17,15 +17,14 @@
 package vm
 
 import (
-	"math/big"
-
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/common/math"
+	"github.com/holiman/uint256"
 )
 
 // calcMemSize64 calculates the required memory size, and returns
 // the size and whether the result overflowed uint64
-func calcMemSize64(off, l *big.Int) (uint64, bool) {
+func calcMemSize64(off, l *uint256.Int) (uint64, bool) {
 	if !l.IsUint64() {
 		return 0, true
 	}
@@ -35,16 +34,16 @@ func calcMemSize64(off, l *big.Int) (uint64, bool) {
 // calcMemSize64WithUint calculates the required memory size, and returns
 // the size and whether the result overflowed uint64
 // Identical to calcMemSize64, but length is a uint64
-func calcMemSize64WithUint(off *big.Int, length64 uint64) (uint64, bool) {
+func calcMemSize64WithUint(off *uint256.Int, length64 uint64) (uint64, bool) {
 	// if length is zero, memsize is always zero, regardless of offset
 	if length64 == 0 {
 		return 0, false
 	}
 	// Check that offset doesn't overflow
-	if !off.IsUint64() {
+	offset64, overflow := off.Uint64WithOverflow()
+	if overflow {
 		return 0, true
 	}
-	offset64 := off.Uint64()
 	val := offset64 + length64
 	// if value < either of it's parts, then it overflowed
 	return val, val < offset64
@@ -64,22 +63,6 @@ func getData(data []byte, start uint64, size uint64) []byte {
 	return common.RightPadBytes(data[start:end], int(size))
 }
 
-// getDataBig returns a slice from the data based on the start and size and pads
-// up to size with zero's. This function is overflow safe.
-func getDataBig(data []byte, start *big.Int, size *big.Int) []byte {
-	dlen := big.NewInt(int64(len(data)))
-
-	s := math.BigMin(start, dlen)
-	e := math.BigMin(new(big.Int).Add(s, size), dlen)
-	return common.RightPadBytes(data[s.Uint64():e.Uint64()], int(size.Uint64()))
-}
-
-// bigUint64 returns the integer casted to a uint64 and returns whether it
-// overflowed in the process.
-func bigUint64(v *big.Int) (uint64, bool) {
-	return v.Uint64(), !v.IsUint64()
-}
-
 // toWordSize returns the ceiled word size required for memory expansion.
 func toWordSize(size uint64) uint64 {
 	if size > math.MaxUint64-31 {

Diff for: core/vm/contract.go

@@ -20,6 +20,7 @@ import (
 	"math/big"
 
 	"github.com/ethereum/go-ethereum/common"
+	"github.com/holiman/uint256"
 )
 
 // ContractRef is a reference to the contract's backing object
@@ -81,11 +82,11 @@ func NewContract(caller ContractRef, object ContractRef, value *big.Int, gas uin
 	return c
 }
 
-func (c *Contract) validJumpdest(dest *big.Int) bool {
-	udest := dest.Uint64()
-	// PC cannot go beyond len(code) and certainly can't be bigger than 63 bits.
+func (c *Contract) validJumpdest(dest *uint256.Int) bool {
+	udest, overflow := dest.Uint64WithOverflow()
+	// PC cannot go beyond len(code) and certainly can't be bigger than 63bits.
 	// Don't bother checking for JUMPDEST in that case.
-	if dest.BitLen() >= 63 || udest >= uint64(len(c.Code)) {
+	if overflow || udest >= uint64(len(c.Code)) {
 		return false
 	}
 	// Only JUMPDESTs allowed for destinations

Diff for: core/vm/eips.go

@@ -20,6 +20,7 @@ import (
 	"fmt"
 
 	"github.com/ethereum/go-ethereum/params"
+	"github.com/holiman/uint256"
 )
 
 // EnableEIP enables the given EIP on the config.
@@ -63,7 +64,7 @@ func enable1884(jt *JumpTable) {
 }
 
 func opSelfBalance(pc *uint64, interpreter *EVMInterpreter, callContext *callCtx) ([]byte, error) {
-	balance := interpreter.intPool.get().Set(interpreter.evm.StateDB.GetBalance(callContext.contract.Address()))
+	balance, _ := uint256.FromBig(interpreter.evm.StateDB.GetBalance(callContext.contract.Address()))
 	callContext.stack.push(balance)
 	return nil, nil
 }
@@ -83,7 +84,7 @@ func enable1344(jt *JumpTable) {
 
 // opChainID implements CHAINID opcode
 func opChainID(pc *uint64, interpreter *EVMInterpreter, callContext *callCtx) ([]byte, error) {
-	chainId := interpreter.intPool.get().Set(interpreter.evm.chainConfig.ChainID)
+	chainId, _ := uint256.FromBig(interpreter.evm.chainConfig.ChainID)
 	callContext.stack.push(chainId)
 	return nil, nil
 }

Diff for: core/vm/evm.go

@@ -352,7 +352,7 @@ func (evm *EVM) StaticCall(caller ContractRef, addr common.Address, input []byte
 	// This doesn't matter on Mainnet, where all empties are gone at the time of Byzantium,
 	// but is the correct thing to do and matters on other networks, in tests, and potential
 	// future scenarios
-	evm.StateDB.AddBalance(addr, bigZero)
+	evm.StateDB.AddBalance(addr, big.NewInt(0))
 
 	// When an error was returned by the EVM or when setting the creation code
 	// above we revert to the snapshot and consume any gas remaining. Additionally

Diff for: core/vm/gas.go

@@ -17,7 +17,7 @@
 package vm
 
 import (
-	"math/big"
+	"github.com/holiman/uint256"
 )
 
 // Gas costs
@@ -34,7 +34,7 @@ const (
 //
 // The cost of gas was changed during the homestead price change HF.
 // As part of EIP 150 (TangerineWhistle), the returned gas is gas - base * 63 / 64.
-func callGas(isEip150 bool, availableGas, base uint64, callCost *big.Int) (uint64, error) {
+func callGas(isEip150 bool, availableGas, base uint64, callCost *uint256.Int) (uint64, error) {
 	if isEip150 {
 		availableGas = availableGas - base
 		gas := availableGas - availableGas/64

Diff for: core/vm/gas_table.go

@@ -70,7 +70,7 @@ func memoryCopierGas(stackpos int) gasFunc {
 			return 0, err
 		}
 		// And gas for copying data, charged per word at param.CopyGas
-		words, overflow := bigUint64(stack.Back(stackpos))
+		words, overflow := stack.Back(stackpos).Uint64WithOverflow()
 		if overflow {
 			return 0, ErrGasUintOverflow
 		}
@@ -96,7 +96,7 @@ var (
 func gasSStore(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))
+		current = evm.StateDB.GetState(contract.Address(), common.Hash(x.Bytes32()))
 	)
 	// The legacy gas metering only takes into consideration the current state
 	// Legacy rules should be applied if we are in Petersburg (removal of EIP-1283)
@@ -131,11 +131,11 @@ func gasSStore(evm *EVM, contract *Contract, stack *Stack, mem *Memory, memorySi
 	// 	  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)
+	value := common.Hash(y.Bytes32())
 	if current == value { // noop (1)
 		return params.NetSstoreNoopGas, nil
 	}
-	original := evm.StateDB.GetCommittedState(contract.Address(), common.BigToHash(x))
+	original := evm.StateDB.GetCommittedState(contract.Address(), common.Hash(x.Bytes32()))
 	if original == current {
 		if original == (common.Hash{}) { // create slot (2.1.1)
 			return params.NetSstoreInitGas, nil
@@ -183,14 +183,14 @@ func gasSStoreEIP2200(evm *EVM, contract *Contract, stack *Stack, mem *Memory, m
 	// Gas sentry honoured, do the actual gas calculation based on the stored value
 	var (
 		y, x    = stack.Back(1), stack.Back(0)
-		current = evm.StateDB.GetState(contract.Address(), common.BigToHash(x))
+		current = evm.StateDB.GetState(contract.Address(), common.Hash(x.Bytes32()))
 	)
-	value := common.BigToHash(y)
+	value := common.Hash(y.Bytes32())
 
 	if current == value { // noop (1)
 		return params.SstoreNoopGasEIP2200, nil
 	}
-	original := evm.StateDB.GetCommittedState(contract.Address(), common.BigToHash(x))
+	original := evm.StateDB.GetCommittedState(contract.Address(), common.Hash(x.Bytes32()))
 	if original == current {
 		if original == (common.Hash{}) { // create slot (2.1.1)
 			return params.SstoreInitGasEIP2200, nil
@@ -219,7 +219,7 @@ func gasSStoreEIP2200(evm *EVM, contract *Contract, stack *Stack, mem *Memory, m
 
 func makeGasLog(n uint64) gasFunc {
 	return func(evm *EVM, contract *Contract, stack *Stack, mem *Memory, memorySize uint64) (uint64, error) {
-		requestedSize, overflow := bigUint64(stack.Back(1))
+		requestedSize, overflow := stack.Back(1).Uint64WithOverflow()
 		if overflow {
 			return 0, ErrGasUintOverflow
 		}
@@ -252,7 +252,7 @@ func gasSha3(evm *EVM, contract *Contract, stack *Stack, mem *Memory, memorySize
 	if err != nil {
 		return 0, err
 	}
-	wordGas, overflow := bigUint64(stack.Back(1))
+	wordGas, overflow := stack.Back(1).Uint64WithOverflow()
 	if overflow {
 		return 0, ErrGasUintOverflow
 	}
@@ -286,7 +286,7 @@ func gasCreate2(evm *EVM, contract *Contract, stack *Stack, mem *Memory, memoryS
 	if err != nil {
 		return 0, err
 	}
-	wordGas, overflow := bigUint64(stack.Back(2))
+	wordGas, overflow := stack.Back(2).Uint64WithOverflow()
 	if overflow {
 		return 0, ErrGasUintOverflow
 	}
@@ -328,8 +328,8 @@ func gasExpEIP158(evm *EVM, contract *Contract, stack *Stack, mem *Memory, memor
 func gasCall(evm *EVM, contract *Contract, stack *Stack, mem *Memory, memorySize uint64) (uint64, error) {
 	var (
 		gas            uint64
-		transfersValue = stack.Back(2).Sign() != 0
-		address        = common.BigToAddress(stack.Back(1))
+		transfersValue = !stack.Back(2).IsZero()
+		address        = common.Address(stack.Back(1).Bytes20())
 	)
 	if evm.chainRules.IsEIP158 {
 		if transfersValue && evm.StateDB.Empty(address) {
@@ -422,7 +422,7 @@ func gasSelfdestruct(evm *EVM, contract *Contract, stack *Stack, mem *Memory, me
 	// EIP150 homestead gas reprice fork:
 	if evm.chainRules.IsEIP150 {
 		gas = params.SelfdestructGasEIP150
-		var address = common.BigToAddress(stack.Back(0))
+		var address = common.Address(stack.Back(0).Bytes20())
 
 		if evm.chainRules.IsEIP158 {
 			// if empty and transfers value