core: vm: refactor file structure (#151)

For support other vm types, this pr modified the core/vm file
structures.

1 files changed, 0 insertions, 484 deletions

diff --git a/core/vm/evm.go b/core/vm/evm.go
deleted file mode 100644
index 64f71e530..000000000
--- a/core/vm/evm.go
+++ /dev/null
@@ -1,484 +0,0 @@
-// Copyright 2014 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"
-	"sync/atomic"
-	"time"
-
-	"github.com/dexon-foundation/dexon/common"
-	"github.com/dexon-foundation/dexon/core/state"
-	"github.com/dexon-foundation/dexon/crypto"
-	"github.com/dexon-foundation/dexon/params"
-)
-
-// emptyCodeHash is used by create to ensure deployment is disallowed to already
-// deployed contract addresses (relevant after the account abstraction).
-var emptyCodeHash = crypto.Keccak256Hash(nil)
-
-type (
-	// CanTransferFunc is the signature of a transfer guard function
-	CanTransferFunc func(StateDB, common.Address, *big.Int) bool
-	// TransferFunc is the signature of a transfer function
-	TransferFunc func(StateDB, common.Address, common.Address, *big.Int)
-	// GetHashFunc returns the nth block hash in the blockchain
-	// and is used by the BLOCKHASH EVM op code.
-	GetHashFunc func(uint64) common.Hash
-	// StateAtFunc returns the statedb given a root hash.
-	StateAtNumberFunc func(uint64) (*state.StateDB, error)
-	// GetRoundHeightFunc returns the round height.
-	GetRoundHeightFunc func(uint64) (uint64, bool)
-)
-
-// run runs the given contract and takes care of running precompiles with a fallback to the byte code interpreter.
-func run(evm *EVM, contract *Contract, input []byte, readOnly bool) ([]byte, error) {
-	if contract.CodeAddr != nil {
-		if *contract.CodeAddr == GovernanceContractAddress {
-			return RunGovernanceContract(evm, input, contract)
-		}
-		precompiles := PrecompiledContractsHomestead
-		if evm.ChainConfig().IsByzantium(evm.BlockNumber) {
-			precompiles = PrecompiledContractsByzantium
-		}
-		if p := precompiles[*contract.CodeAddr]; p != nil {
-			return RunPrecompiledContract(p, input, contract)
-		}
-	}
-	for _, interpreter := range evm.interpreters {
-		if interpreter.CanRun(contract.Code) {
-			if evm.interpreter != interpreter {
-				// Ensure that the interpreter pointer is set back
-				// to its current value upon return.
-				defer func(i Interpreter) {
-					evm.interpreter = i
-				}(evm.interpreter)
-				evm.interpreter = interpreter
-			}
-			return interpreter.Run(contract, input, readOnly)
-		}
-	}
-	return nil, ErrNoCompatibleInterpreter
-}
-
-// Context provides the EVM with auxiliary information. Once provided
-// it shouldn't be modified.
-type Context struct {
-	// CanTransfer returns whether the account contains
-	// sufficient ether to transfer the value
-	CanTransfer CanTransferFunc
-	// Transfer transfers ether from one account to the other
-	Transfer TransferFunc
-	// GetHash returns the hash corresponding to n
-	GetHash GetHashFunc
-	// StateAtNumber returns the statedb given a root hash.
-	StateAtNumber StateAtNumberFunc
-	// GetRoundHeight returns the round height.
-	GetRoundHeight GetRoundHeightFunc
-
-	// Message information
-	Origin   common.Address // Provides information for ORIGIN
-	GasPrice *big.Int       // Provides information for GASPRICE
-
-	// Block information
-	Coinbase    common.Address // Provides information for COINBASE
-	GasLimit    uint64         // Provides information for GASLIMIT
-	BlockNumber *big.Int       // Provides information for NUMBER
-	Time        *big.Int       // Provides information for TIME
-	Randomness  []byte         // Provides information for RAND
-	Difficulty  *big.Int       // Provides information for DIFFICULTY
-}
-
-// EVM is the Ethereum Virtual Machine base object and provides
-// the necessary tools to run a contract on the given state with
-// the provided context. It should be noted that any error
-// generated through any of the calls should be considered a
-// revert-state-and-consume-all-gas operation, no checks on
-// specific errors should ever be performed. The interpreter makes
-// sure that any errors generated are to be considered faulty code.
-//
-// The EVM should never be reused and is not thread safe.
-type EVM struct {
-	// Context provides auxiliary blockchain related information
-	Context
-	// StateDB gives access to the underlying state
-	StateDB StateDB
-	// Depth is the current call stack
-	depth int
-
-	// chainConfig contains information about the current chain
-	chainConfig *params.ChainConfig
-	// chain rules contains the chain rules for the current epoch
-	chainRules params.Rules
-	// virtual machine configuration options used to initialise the
-	// evm.
-	vmConfig Config
-	// global (to this context) ethereum virtual machine
-	// used throughout the execution of the tx.
-	interpreters []Interpreter
-	interpreter  Interpreter
-	// abort is used to abort the EVM calling operations
-	// NOTE: must be set atomically
-	abort int32
-	// callGasTemp holds the gas available for the current call. This is needed because the
-	// available gas is calculated in gasCall* according to the 63/64 rule and later
-	// applied in opCall*.
-	callGasTemp uint64
-}
-
-// NewEVM returns a new EVM. The returned EVM is not thread safe and should
-// only ever be used *once*.
-func NewEVM(ctx Context, statedb StateDB, chainConfig *params.ChainConfig, vmConfig Config) *EVM {
-	evm := &EVM{
-		Context:      ctx,
-		StateDB:      statedb,
-		vmConfig:     vmConfig,
-		chainConfig:  chainConfig,
-		chainRules:   chainConfig.Rules(ctx.BlockNumber),
-		interpreters: make([]Interpreter, 0, 1),
-	}
-
-	if chainConfig.IsEWASM(ctx.BlockNumber) {
-		// to be implemented by EVM-C and Wagon PRs.
-		// if vmConfig.EWASMInterpreter != "" {
-		//  extIntOpts := strings.Split(vmConfig.EWASMInterpreter, ":")
-		//  path := extIntOpts[0]
-		//  options := []string{}
-		//  if len(extIntOpts) > 1 {
-		//    options = extIntOpts[1..]
-		//  }
-		//  evm.interpreters = append(evm.interpreters, NewEVMVCInterpreter(evm, vmConfig, options))
-		// } else {
-		// 	evm.interpreters = append(evm.interpreters, NewEWASMInterpreter(evm, vmConfig))
-		// }
-		panic("No supported ewasm interpreter yet.")
-	}
-
-	// vmConfig.EVMInterpreter will be used by EVM-C, it won't be checked here
-	// as we always want to have the built-in EVM as the failover option.
-	evm.interpreters = append(evm.interpreters, NewEVMInterpreter(evm, vmConfig))
-	evm.interpreter = evm.interpreters[0]
-
-	return evm
-}
-
-// Cancel cancels any running EVM operation. This may be called concurrently and
-// it's safe to be called multiple times.
-func (evm *EVM) Cancel() {
-	atomic.StoreInt32(&evm.abort, 1)
-}
-
-// Interpreter returns the current interpreter
-func (evm *EVM) Interpreter() Interpreter {
-	return evm.interpreter
-}
-
-// Call executes the contract associated with the addr with the given input as
-// parameters. It also handles any necessary value transfer required and takes
-// the necessary steps to create accounts and reverses the state in case of an
-// execution error or failed value transfer.
-func (evm *EVM) Call(caller ContractRef, addr common.Address, input []byte, gas uint64, value *big.Int) (ret []byte, leftOverGas uint64, err error) {
-	if evm.vmConfig.NoRecursion && evm.depth > 0 {
-		return nil, gas, nil
-	}
-
-	// Fail if we're trying to execute above the call depth limit
-	if evm.depth > int(params.CallCreateDepth) {
-		return nil, gas, ErrDepth
-	}
-	// Fail if we're trying to transfer more than the available balance
-	if !evm.Context.CanTransfer(evm.StateDB, caller.Address(), value) {
-		return nil, gas, ErrInsufficientBalance
-	}
-
-	var (
-		to       = AccountRef(addr)
-		snapshot = evm.StateDB.Snapshot()
-	)
-	if !evm.StateDB.Exist(addr) {
-		precompiles := PrecompiledContractsHomestead
-		if evm.ChainConfig().IsByzantium(evm.BlockNumber) {
-			precompiles = PrecompiledContractsByzantium
-		}
-		if precompiles[addr] == nil && evm.ChainConfig().IsEIP158(evm.BlockNumber) && value.Sign() == 0 && addr != GovernanceContractAddress {
-			// Calling a non existing account, don't do anything, but ping the tracer
-			if evm.vmConfig.Debug && evm.depth == 0 {
-				evm.vmConfig.Tracer.CaptureStart(caller.Address(), addr, false, input, gas, value)
-				evm.vmConfig.Tracer.CaptureEnd(ret, 0, 0, nil)
-			}
-			return nil, gas, nil
-		}
-		evm.StateDB.CreateAccount(addr)
-	}
-	evm.Transfer(evm.StateDB, caller.Address(), to.Address(), value)
-	// Initialise a new contract and set the code that is to be used by the EVM.
-	// The contract is a scoped environment for this execution context only.
-	contract := NewContract(caller, to, value, gas)
-	contract.SetCallCode(&addr, evm.StateDB.GetCodeHash(addr), evm.StateDB.GetCode(addr))
-
-	// Even if the account has no code, we need to continue because it might be a precompile
-	start := time.Now()
-
-	// Capture the tracer start/end events in debug mode
-	if evm.vmConfig.Debug && evm.depth == 0 {
-		evm.vmConfig.Tracer.CaptureStart(caller.Address(), addr, false, input, gas, value)
-
-		defer func() { // Lazy evaluation of the parameters
-			evm.vmConfig.Tracer.CaptureEnd(ret, gas-contract.Gas, time.Since(start), err)
-		}()
-	}
-	ret, err = run(evm, contract, input, false)
-
-	// 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
-	// when we're in homestead this also counts for code storage gas errors.
-	if err != nil {
-		evm.StateDB.RevertToSnapshot(snapshot)
-		if err != errExecutionReverted {
-			contract.UseGas(contract.Gas)
-		}
-	}
-	return ret, contract.Gas, err
-}
-
-// CallCode executes the contract associated with the addr with the given input
-// as parameters. It also handles any necessary value transfer required and takes
-// the necessary steps to create accounts and reverses the state in case of an
-// execution error or failed value transfer.
-//
-// CallCode differs from Call in the sense that it executes the given address'
-// code with the caller as context.
-func (evm *EVM) CallCode(caller ContractRef, addr common.Address, input []byte, gas uint64, value *big.Int) (ret []byte, leftOverGas uint64, err error) {
-	if evm.vmConfig.NoRecursion && evm.depth > 0 {
-		return nil, gas, nil
-	}
-
-	// Fail if we're trying to execute above the call depth limit
-	if evm.depth > int(params.CallCreateDepth) {
-		return nil, gas, ErrDepth
-	}
-	// Fail if we're trying to transfer more than the available balance
-	if !evm.CanTransfer(evm.StateDB, caller.Address(), value) {
-		return nil, gas, ErrInsufficientBalance
-	}
-
-	var (
-		snapshot = evm.StateDB.Snapshot()
-		to       = AccountRef(caller.Address())
-	)
-	// initialise a new contract and set the code that is to be used by the
-	// EVM. The contract is a scoped environment for this execution context
-	// only.
-	contract := NewContract(caller, to, value, gas)
-	contract.SetCallCode(&addr, evm.StateDB.GetCodeHash(addr), evm.StateDB.GetCode(addr))
-
-	ret, err = run(evm, contract, input, false)
-	if err != nil {
-		evm.StateDB.RevertToSnapshot(snapshot)
-		if err != errExecutionReverted {
-			contract.UseGas(contract.Gas)
-		}
-	}
-	return ret, contract.Gas, err
-}
-
-// DelegateCall executes the contract associated with the addr with the given input
-// as parameters. It reverses the state in case of an execution error.
-//
-// DelegateCall differs from CallCode in the sense that it executes the given address'
-// code with the caller as context and the caller is set to the caller of the caller.
-func (evm *EVM) DelegateCall(caller ContractRef, addr common.Address, input []byte, gas uint64) (ret []byte, leftOverGas uint64, err error) {
-	if evm.vmConfig.NoRecursion && evm.depth > 0 {
-		return nil, gas, nil
-	}
-	// Fail if we're trying to execute above the call depth limit
-	if evm.depth > int(params.CallCreateDepth) {
-		return nil, gas, ErrDepth
-	}
-
-	var (
-		snapshot = evm.StateDB.Snapshot()
-		to       = AccountRef(caller.Address())
-	)
-
-	// Initialise a new contract and make initialise the delegate values
-	contract := NewContract(caller, to, nil, gas).AsDelegate()
-	contract.SetCallCode(&addr, evm.StateDB.GetCodeHash(addr), evm.StateDB.GetCode(addr))
-
-	ret, err = run(evm, contract, input, false)
-	if err != nil {
-		evm.StateDB.RevertToSnapshot(snapshot)
-		if err != errExecutionReverted {
-			contract.UseGas(contract.Gas)
-		}
-	}
-	return ret, contract.Gas, err
-}
-
-// StaticCall executes the contract associated with the addr with the given input
-// as parameters while disallowing any modifications to the state during the call.
-// Opcodes that attempt to perform such modifications will result in exceptions
-// instead of performing the modifications.
-func (evm *EVM) StaticCall(caller ContractRef, addr common.Address, input []byte, gas uint64) (ret []byte, leftOverGas uint64, err error) {
-	if evm.vmConfig.NoRecursion && evm.depth > 0 {
-		return nil, gas, nil
-	}
-	// Fail if we're trying to execute above the call depth limit
-	if evm.depth > int(params.CallCreateDepth) {
-		return nil, gas, ErrDepth
-	}
-
-	var (
-		to       = AccountRef(addr)
-		snapshot = evm.StateDB.Snapshot()
-	)
-	// Initialise a new contract and set the code that is to be used by the
-	// EVM. The contract is a scoped environment for this execution context
-	// only.
-	contract := NewContract(caller, to, new(big.Int), gas)
-	contract.SetCallCode(&addr, evm.StateDB.GetCodeHash(addr), evm.StateDB.GetCode(addr))
-
-	// We do an AddBalance of zero here, just in order to trigger a touch.
-	// 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)
-
-	// 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
-	// when we're in Homestead this also counts for code storage gas errors.
-	ret, err = run(evm, contract, input, true)
-	if err != nil {
-		evm.StateDB.RevertToSnapshot(snapshot)
-		if err != errExecutionReverted {
-			contract.UseGas(contract.Gas)
-		}
-	}
-	return ret, contract.Gas, err
-}
-
-type codeAndHash struct {
-	code []byte
-	hash common.Hash
-}
-
-func (c *codeAndHash) Hash() common.Hash {
-	if c.hash == (common.Hash{}) {
-		c.hash = crypto.Keccak256Hash(c.code)
-	}
-	return c.hash
-}
-
-// create creates a new contract using code as deployment code.
-func (evm *EVM) create(caller ContractRef, codeAndHash *codeAndHash, gas uint64, value *big.Int, address common.Address) ([]byte, common.Address, uint64, error) {
-	// Depth check execution. Fail if we're trying to execute above the
-	// limit.
-	if evm.depth > int(params.CallCreateDepth) {
-		return nil, common.Address{}, gas, ErrDepth
-	}
-	if !evm.CanTransfer(evm.StateDB, caller.Address(), value) {
-		return nil, common.Address{}, gas, ErrInsufficientBalance
-	}
-	nonce := evm.StateDB.GetNonce(caller.Address())
-	evm.StateDB.SetNonce(caller.Address(), nonce+1)
-
-	// Ensure there's no existing contract already at the designated address
-	contractHash := evm.StateDB.GetCodeHash(address)
-	if evm.StateDB.GetNonce(address) != 0 || (contractHash != (common.Hash{}) && contractHash != emptyCodeHash) {
-		return nil, common.Address{}, 0, ErrContractAddressCollision
-	}
-	// Create a new account on the state
-	snapshot := evm.StateDB.Snapshot()
-	evm.StateDB.CreateAccount(address)
-	if evm.ChainConfig().IsEIP158(evm.BlockNumber) {
-		evm.StateDB.SetNonce(address, 1)
-	}
-	evm.Transfer(evm.StateDB, caller.Address(), address, value)
-
-	// initialise a new contract and set the code that is to be used by the
-	// EVM. The contract is a scoped environment for this execution context
-	// only.
-	contract := NewContract(caller, AccountRef(address), value, gas)
-	contract.SetCodeOptionalHash(&address, codeAndHash)
-
-	if evm.vmConfig.NoRecursion && evm.depth > 0 {
-		return nil, address, gas, nil
-	}
-
-	if evm.vmConfig.Debug && evm.depth == 0 {
-		evm.vmConfig.Tracer.CaptureStart(caller.Address(), address, true, codeAndHash.code, gas, value)
-	}
-	start := time.Now()
-
-	ret, err := run(evm, contract, nil, false)
-
-	// check whether the max code size has been exceeded
-	maxCodeSizeExceeded := evm.ChainConfig().IsEIP158(evm.BlockNumber) && len(ret) > params.MaxCodeSize
-	// if the contract creation ran successfully and no errors were returned
-	// calculate the gas required to store the code. If the code could not
-	// be stored due to not enough gas set an error and let it be handled
-	// by the error checking condition below.
-	if err == nil && !maxCodeSizeExceeded {
-		createDataGas := uint64(len(ret)) * params.CreateDataGas
-		if contract.UseGas(createDataGas) {
-			evm.StateDB.SetCode(address, ret)
-		} else {
-			err = ErrCodeStoreOutOfGas
-		}
-	}
-
-	// 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
-	// when we're in homestead this also counts for code storage gas errors.
-	if maxCodeSizeExceeded || (err != nil && (evm.ChainConfig().IsHomestead(evm.BlockNumber) || err != ErrCodeStoreOutOfGas)) {
-		evm.StateDB.RevertToSnapshot(snapshot)
-		if err != errExecutionReverted {
-			contract.UseGas(contract.Gas)
-		}
-	}
-	// Assign err if contract code size exceeds the max while the err is still empty.
-	if maxCodeSizeExceeded && err == nil {
-		err = errMaxCodeSizeExceeded
-	}
-	if evm.vmConfig.Debug && evm.depth == 0 {
-		evm.vmConfig.Tracer.CaptureEnd(ret, gas-contract.Gas, time.Since(start), err)
-	}
-	return ret, address, contract.Gas, err
-
-}
-
-// Create creates a new contract using code as deployment code.
-func (evm *EVM) Create(caller ContractRef, code []byte, gas uint64, value *big.Int) (ret []byte, contractAddr common.Address, leftOverGas uint64, err error) {
-	contractAddr = crypto.CreateAddress(caller.Address(), evm.StateDB.GetNonce(caller.Address()))
-	return evm.create(caller, &codeAndHash{code: code}, gas, value, contractAddr)
-}
-
-// Create2 creates a new contract using code as deployment code.
-//
-// The different between Create2 with Create is Create2 uses sha3(0xff ++ msg.sender ++ salt ++ sha3(init_code))[12:]
-// instead of the usual sender-and-nonce-hash as the address where the contract is initialized at.
-func (evm *EVM) Create2(caller ContractRef, code []byte, gas uint64, endowment *big.Int, salt *big.Int) (ret []byte, contractAddr common.Address, leftOverGas uint64, err error) {
-	codeAndHash := &codeAndHash{code: code}
-	contractAddr = crypto.CreateAddress2(caller.Address(), common.BigToHash(salt), codeAndHash.Hash().Bytes())
-	return evm.create(caller, codeAndHash, gas, endowment, contractAddr)
-}
-
-// ChainConfig returns the environment's chain configuration
-func (evm *EVM) ChainConfig() *params.ChainConfig { return evm.chainConfig }
-
-// IsBlockProposer returns whether or not we are a block proposer.
-func (evm *EVM) IsBlockProposer() bool { return evm.vmConfig.IsBlockProposer }