core: Added EVM configuration options

The EVM is now initialised with an additional configured object that
allows you to turn on debugging options.

12 files changed, 336 insertions, 145 deletions

diff --git a/core/vm/common.go b/core/vm/common.go
index f73bc1527..2878b92d2 100644
--- a/core/vm/common.go
+++ b/core/vm/common.go
@@ -24,11 +24,6 @@ import (
 	"github.com/ethereum/go-ethereum/params"
 )
 
-// Global Debug flag indicating Debug VM (full logging)
-var Debug bool
-
-var GenerateStructLogs bool = false
-
 // Type is the VM type accepted by **NewVm**
 type Type byte
 
diff --git a/core/vm/contract.go b/core/vm/contract.go
index d23995218..59e8f1aa6 100644
--- a/core/vm/contract.go
+++ b/core/vm/contract.go
@@ -28,7 +28,7 @@ type ContractRef interface {
 	Address() common.Address
 	Value() *big.Int
 	SetCode([]byte)
-	EachStorage(cb func(key, value []byte))
+	ForEachStorage(callback func(key, value common.Hash) bool)
 }
 
 // Contract represents an ethereum contract in the state database. It contains
@@ -156,6 +156,6 @@ func (self *Contract) SetCallCode(addr *common.Address, code []byte) {
 
 // EachStorage iterates the contract's storage and calls a method for every key
 // value pair.
-func (self *Contract) EachStorage(cb func(key, value []byte)) {
-	self.caller.EachStorage(cb)
+func (self *Contract) ForEachStorage(cb func(key, value common.Hash) bool) {
+	self.caller.ForEachStorage(cb)
 }
diff --git a/core/vm/environment.go b/core/vm/environment.go
index 3c530962b..568218edd 100644
--- a/core/vm/environment.go
+++ b/core/vm/environment.go
@@ -22,9 +22,6 @@ import (
 	"github.com/ethereum/go-ethereum/common"
 )
 
-// Environment is is required by the virtual machine to get information from
-// it's own isolated environment.
-
 // Environment is an EVM requirement and helper which allows access to outside
 // information such as states.
 type Environment interface {
@@ -54,12 +51,8 @@ type Environment interface {
 	Transfer(from, to Account, amount *big.Int)
 	// Adds a LOG to the state
 	AddLog(*Log)
-	// Adds a structured log to the env
-	AddStructLog(StructLog)
-	// Returns all coalesced structured logs
-	StructLogs() []StructLog
 	// Type of the VM
-	Vm() *Vm
+	Vm() Vm
 	// Current calling depth
 	Depth() int
 	SetDepth(i int)
@@ -74,7 +67,15 @@ type Environment interface {
 	Create(me ContractRef, data []byte, gas, price, value *big.Int) ([]byte, common.Address, error)
 }
 
-// Database is a EVM database for full state querying
+// Vm is the basic interface for an implementation of the EVM.
+type Vm interface {
+	// Run should execute the given contract with the input given in in
+	// and return the contract execution return bytes or an error if it
+	// failed.
+	Run(c *Contract, in []byte) ([]byte, error)
+}
+
+// Database is a EVM database for full state querying.
 type Database interface {
 	GetAccount(common.Address) Account
 	CreateAccount(common.Address) Account
@@ -99,19 +100,7 @@ type Database interface {
 	IsDeleted(common.Address) bool
 }
 
-// StructLog is emitted to the Environment each cycle and lists information about the current internal state
-// prior to the execution of the statement.
-type StructLog struct {
-	Pc      uint64
-	Op      OpCode
-	Gas     *big.Int
-	GasCost *big.Int
-	Memory  []byte
-	Stack   []*big.Int
-	Storage map[common.Hash][]byte
-	Err     error
-}
-
+// Account represents a contract or basic ethereum account.
 type Account interface {
 	SubBalance(amount *big.Int)
 	AddBalance(amount *big.Int)
@@ -121,6 +110,6 @@ type Account interface {
 	Address() common.Address
 	ReturnGas(*big.Int, *big.Int)
 	SetCode([]byte)
-	EachStorage(cb func(key, value []byte))
+	ForEachStorage(cb func(key, value common.Hash) bool)
 	Value() *big.Int
 }
diff --git a/core/vm/jit_test.go b/core/vm/jit_test.go
index 5fac0156f..43b1dee2a 100644
--- a/core/vm/jit_test.go
+++ b/core/vm/jit_test.go
@@ -125,17 +125,17 @@ type vmBench struct {
 
 type account struct{}
 
-func (account) SubBalance(amount *big.Int)             {}
-func (account) AddBalance(amount *big.Int)             {}
-func (account) SetAddress(common.Address)              {}
-func (account) Value() *big.Int                        { return nil }
-func (account) SetBalance(*big.Int)                    {}
-func (account) SetNonce(uint64)                        {}
-func (account) Balance() *big.Int                      { return nil }
-func (account) Address() common.Address                { return common.Address{} }
-func (account) ReturnGas(*big.Int, *big.Int)           {}
-func (account) SetCode([]byte)                         {}
-func (account) EachStorage(cb func(key, value []byte)) {}
+func (account) SubBalance(amount *big.Int)                          {}
+func (account) AddBalance(amount *big.Int)                          {}
+func (account) SetAddress(common.Address)                           {}
+func (account) Value() *big.Int                                     { return nil }
+func (account) SetBalance(*big.Int)                                 {}
+func (account) SetNonce(uint64)                                     {}
+func (account) Balance() *big.Int                                   { return nil }
+func (account) Address() common.Address                             { return common.Address{} }
+func (account) ReturnGas(*big.Int, *big.Int)                        {}
+func (account) SetCode([]byte)                                      {}
+func (account) ForEachStorage(cb func(key, value common.Hash) bool) {}
 
 func runVmBench(test vmBench, b *testing.B) {
 	var sender account
@@ -165,16 +165,16 @@ func runVmBench(test vmBench, b *testing.B) {
 type Env struct {
 	gasLimit *big.Int
 	depth    int
-	evm      *Vm
+	evm      *EVM
 }
 
 func NewEnv() *Env {
 	env := &Env{gasLimit: big.NewInt(10000), depth: 0}
-	env.evm = EVM(env)
+	env.evm = New(env, nil)
 	return env
 }
 
-func (self *Env) Vm() *Vm                { return self.evm }
+func (self *Env) Vm() Vm                 { return self.evm }
 func (self *Env) Origin() common.Address { return common.Address{} }
 func (self *Env) BlockNumber() *big.Int  { return big.NewInt(0) }
 func (self *Env) AddStructLog(log StructLog) {
diff --git a/core/vm/logger.go b/core/vm/logger.go
index 2bd02319f..8d333dfd2 100644
--- a/core/vm/logger.go
+++ b/core/vm/logger.go
@@ -18,12 +18,143 @@ package vm
 
 import (
 	"fmt"
+	"math/big"
 	"os"
 	"unicode"
 
 	"github.com/ethereum/go-ethereum/common"
 )
 
+type Storage map[common.Hash]common.Hash
+
+func (self Storage) Copy() Storage {
+	cpy := make(Storage)
+	for key, value := range self {
+		cpy[key] = value
+	}
+
+	return cpy
+}
+
+// StructLogCollector is the basic interface to capture emited logs by the EVM logger.
+type StructLogCollector interface {
+	// Adds the structured log to the collector.
+	AddStructLog(StructLog)
+}
+
+// LogConfig are the configuration options for structured logger the EVM
+type LogConfig struct {
+	DisableMemory  bool               // disable memory capture
+	DisableStack   bool               // disable stack capture
+	DisableStorage bool               // disable storage capture
+	FullStorage    bool               // show full storage (slow)
+	Collector      StructLogCollector // the log collector
+}
+
+// StructLog is emitted to the Environment each cycle and lists information about the current internal state
+// prior to the execution of the statement.
+type StructLog struct {
+	Pc      uint64
+	Op      OpCode
+	Gas     *big.Int
+	GasCost *big.Int
+	Memory  []byte
+	Stack   []*big.Int
+	Storage map[common.Hash]common.Hash
+	Depth   int
+	Err     error
+}
+
+// Logger is an EVM state logger and implements VmLogger.
+//
+// Logger can capture state based on the given Log configuration and also keeps
+// a track record of modified storage which is used in reporting snapshots of the
+// contract their storage.
+type Logger struct {
+	cfg LogConfig
+
+	env           Environment
+	changedValues map[common.Address]Storage
+}
+
+// newLogger returns a new logger
+func newLogger(cfg LogConfig, env Environment) *Logger {
+	return &Logger{
+		cfg:           cfg,
+		env:           env,
+		changedValues: make(map[common.Address]Storage),
+	}
+}
+
+// captureState logs a new structured log message and pushes it out to the environment
+//
+// captureState also tracks SSTORE ops to track dirty values.
+func (l *Logger) captureState(pc uint64, op OpCode, gas, cost *big.Int, memory *Memory, stack *stack, contract *Contract, err error) {
+	// short circuit if no log collector is present
+	if l.cfg.Collector == nil {
+		return
+	}
+
+	// initialise new changed values storage container for this contract
+	// if not present.
+	if l.changedValues[contract.Address()] == nil {
+		l.changedValues[contract.Address()] = make(Storage)
+	}
+
+	// capture SSTORE opcodes and determine the changed value and store
+	// it in the local storage container. NOTE: we do not need to do any
+	// range checks here because that's already handler prior to calling
+	// this function.
+	switch op {
+	case SSTORE:
+		var (
+			value   = common.BigToHash(stack.data[stack.len()-2])
+			address = common.BigToHash(stack.data[stack.len()-1])
+		)
+		l.changedValues[contract.Address()][address] = value
+	}
+
+	// copy a snapstot of the current memory state to a new buffer
+	var mem []byte
+	if !l.cfg.DisableMemory {
+		mem = make([]byte, len(memory.Data()))
+		copy(mem, memory.Data())
+	}
+
+	// copy a snapshot of the current stack state to a new buffer
+	var stck []*big.Int
+	if !l.cfg.DisableStack {
+		stck = make([]*big.Int, len(stack.Data()))
+		for i, item := range stack.Data() {
+			stck[i] = new(big.Int).Set(item)
+		}
+	}
+
+	// Copy the storage based on the settings specified in the log config. If full storage
+	// is disabled (default) we can use the simple Storage.Copy method, otherwise we use
+	// the state object to query for all values (slow process).
+	var storage Storage
+	if !l.cfg.DisableStorage {
+		if l.cfg.FullStorage {
+			storage = make(Storage)
+			// Get the contract account and loop over each storage entry. This may involve looping over
+			// the trie and is a very expensive process.
+			l.env.Db().GetAccount(contract.Address()).ForEachStorage(func(key, value common.Hash) bool {
+				storage[key] = value
+				// Return true, indicating we'd like to continue.
+				return true
+			})
+		} else {
+			// copy a snapshot of the current storage to a new container.
+			storage = l.changedValues[contract.Address()].Copy()
+		}
+	}
+	// create a new snaptshot of the EVM.
+	log := StructLog{pc, op, new(big.Int).Set(gas), cost, mem, stck, storage, l.env.Depth(), err}
+	// Add the log to the collector
+	l.cfg.Collector.AddStructLog(log)
+}
+
 // StdErrFormat formats a slice of StructLogs to human readable format
 func StdErrFormat(logs []StructLog) {
 	fmt.Fprintf(os.Stderr, "VM STAT %d OPs\n", len(logs))
@@ -61,7 +192,7 @@ func StdErrFormat(logs []StructLog) {
 
 		fmt.Fprintln(os.Stderr, "STORAGE =", len(log.Storage))
 		for h, item := range log.Storage {
-			fmt.Fprintf(os.Stderr, "%x: %x\n", h, common.LeftPadBytes(item, 32))
+			fmt.Fprintf(os.Stderr, "%x: %x\n", h, item)
 		}
 		fmt.Fprintln(os.Stderr)
 	}
diff --git a/core/vm/logger_test.go b/core/vm/logger_test.go
new file mode 100644
index 000000000..77fee2c64
--- /dev/null
+++ b/core/vm/logger_test.go
@@ -0,0 +1,104 @@
+// 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"
+	"testing"
+
+	"github.com/ethereum/go-ethereum/common"
+)
+
+type dummyContractRef struct {
+	calledForEach bool
+}
+
+func (dummyContractRef) ReturnGas(*big.Int, *big.Int) {}
+func (dummyContractRef) Address() common.Address      { return common.Address{} }
+func (dummyContractRef) Value() *big.Int              { return new(big.Int) }
+func (dummyContractRef) SetCode([]byte)               {}
+func (d *dummyContractRef) ForEachStorage(callback func(key, value common.Hash) bool) {
+	d.calledForEach = true
+}
+func (d *dummyContractRef) SubBalance(amount *big.Int) {}
+func (d *dummyContractRef) AddBalance(amount *big.Int) {}
+func (d *dummyContractRef) SetBalance(*big.Int)        {}
+func (d *dummyContractRef) SetNonce(uint64)            {}
+func (d *dummyContractRef) Balance() *big.Int          { return new(big.Int) }
+
+type dummyEnv struct {
+	*Env
+	ref *dummyContractRef
+}
+
+func newDummyEnv(ref *dummyContractRef) *dummyEnv {
+	return &dummyEnv{
+		Env: NewEnv(),
+		ref: ref,
+	}
+}
+func (d dummyEnv) GetAccount(common.Address) Account {
+	return d.ref
+}
+func (d dummyEnv) AddStructLog(StructLog) {}
+
+func TestStoreCapture(t *testing.T) {
+	var (
+		env      = NewEnv()
+		logger   = newLogger(LogConfig{Collector: env}, env)
+		mem      = NewMemory()
+		stack    = newstack()
+		contract = NewContract(&dummyContractRef{}, &dummyContractRef{}, new(big.Int), new(big.Int), new(big.Int))
+	)
+	stack.push(big.NewInt(1))
+	stack.push(big.NewInt(0))
+
+	var index common.Hash
+
+	logger.captureState(0, SSTORE, new(big.Int), new(big.Int), mem, stack, contract, nil)
+	if len(logger.changedValues[contract.Address()]) == 0 {
+		t.Fatalf("expected exactly 1 changed value on address %x, got %d", contract.Address(), len(logger.changedValues[contract.Address()]))
+	}
+
+	exp := common.BigToHash(big.NewInt(1))
+	if logger.changedValues[contract.Address()][index] != exp {
+		t.Errorf("expected %x, got %x", exp, logger.changedValues[contract.Address()][index])
+	}
+}
+
+func TestStorageCapture(t *testing.T) {
+	t.Skip("implementing this function is difficult. it requires all sort of interfaces to be implemented which isn't trivial. The value (the actual test) isn't worth it")
+	var (
+		ref      = &dummyContractRef{}
+		contract = NewContract(ref, ref, new(big.Int), new(big.Int), new(big.Int))
+		env      = newDummyEnv(ref)
+		logger   = newLogger(LogConfig{Collector: env}, env)
+		mem      = NewMemory()
+		stack    = newstack()
+	)
+
+	logger.captureState(0, STOP, new(big.Int), new(big.Int), mem, stack, contract, nil)
+	if ref.calledForEach {
+		t.Error("didn't expect for each to be called")
+	}
+
+	logger = newLogger(LogConfig{Collector: env, FullStorage: true}, env)
+	logger.captureState(0, STOP, new(big.Int), new(big.Int), mem, stack, contract, nil)
+	if !ref.calledForEach {
+		t.Error("expected for each to be called")
+	}
+}
diff --git a/core/vm/runtime/env.go b/core/vm/runtime/env.go
index e9bf828ea..ce64d7117 100644
--- a/core/vm/runtime/env.go
+++ b/core/vm/runtime/env.go
@@ -42,7 +42,7 @@ type Env struct {
 
 	getHashFn func(uint64) common.Hash
 
-	evm *vm.Vm
+	evm *vm.EVM
 }
 
 // NewEnv returns a new vm.Environment
@@ -56,7 +56,15 @@ func NewEnv(cfg *Config, state *state.StateDB) vm.Environment {
 		difficulty: cfg.Difficulty,
 		gasLimit:   cfg.GasLimit,
 	}
-	env.evm = vm.EVM(env)
+	env.evm = vm.New(env, &vm.Config{
+		Debug:     cfg.Debug,
+		EnableJit: !cfg.DisableJit,
+		ForceJit:  !cfg.DisableJit,
+
+		Logger: vm.LogConfig{
+			Collector: env,
+		},
+	})
 
 	return env
 }
@@ -69,7 +77,7 @@ func (self *Env) AddStructLog(log vm.StructLog) {
 	self.logs = append(self.logs, log)
 }
 
-func (self *Env) Vm() *vm.Vm               { return self.evm }
+func (self *Env) Vm() vm.Vm                { return self.evm }
 func (self *Env) Origin() common.Address   { return self.origin }
 func (self *Env) BlockNumber() *big.Int    { return self.number }
 func (self *Env) Coinbase() common.Address { return self.coinbase }
diff --git a/core/vm/runtime/runtime.go b/core/vm/runtime/runtime.go
index 3e6057142..f88a20170 100644
--- a/core/vm/runtime/runtime.go
+++ b/core/vm/runtime/runtime.go
@@ -22,7 +22,6 @@ import (
 
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/core/state"
-	"github.com/ethereum/go-ethereum/core/vm"
 	"github.com/ethereum/go-ethereum/crypto"
 	"github.com/ethereum/go-ethereum/ethdb"
 )
@@ -84,17 +83,6 @@ func Execute(code, input []byte, cfg *Config) ([]byte, *state.StateDB, error) {
 	}
 	setDefaults(cfg)
 
-	// defer the call to setting back the original values
-	defer func(debug, forceJit, enableJit bool) {
-		vm.Debug = debug
-		vm.ForceJit = forceJit
-		vm.EnableJit = enableJit
-	}(vm.Debug, vm.ForceJit, vm.EnableJit)
-
-	vm.ForceJit = !cfg.DisableJit
-	vm.EnableJit = !cfg.DisableJit
-	vm.Debug = cfg.Debug
-
 	if cfg.State == nil {
 		db, _ := ethdb.NewMemDatabase()
 		cfg.State, _ = state.New(common.Hash{}, db)
@@ -117,9 +105,6 @@ func Execute(code, input []byte, cfg *Config) ([]byte, *state.StateDB, error) {
 		cfg.Value,
 	)
 
-	if cfg.Debug {
-		vm.StdErrFormat(vmenv.StructLogs())
-	}
 	return ret, cfg.State, err
 }
 
@@ -131,17 +116,6 @@ func Execute(code, input []byte, cfg *Config) ([]byte, *state.StateDB, error) {
 func Call(address common.Address, input []byte, cfg *Config) ([]byte, error) {
 	setDefaults(cfg)
 
-	// defer the call to setting back the original values
-	defer func(debug, forceJit, enableJit bool) {
-		vm.Debug = debug
-		vm.ForceJit = forceJit
-		vm.EnableJit = enableJit
-	}(vm.Debug, vm.ForceJit, vm.EnableJit)
-
-	vm.ForceJit = !cfg.DisableJit
-	vm.EnableJit = !cfg.DisableJit
-	vm.Debug = cfg.Debug
-
 	vmenv := NewEnv(cfg, cfg.State)
 
 	sender := cfg.State.GetOrNewStateObject(cfg.Origin)
@@ -155,8 +129,5 @@ func Call(address common.Address, input []byte, cfg *Config) ([]byte, error) {
 		cfg.Value,
 	)
 
-	if cfg.Debug {
-		vm.StdErrFormat(vmenv.StructLogs())
-	}
 	return ret, err
 }
diff --git a/core/vm/runtime/runtime_test.go b/core/vm/runtime/runtime_test.go
index e5183052f..88c76c731 100644
--- a/core/vm/runtime/runtime_test.go
+++ b/core/vm/runtime/runtime_test.go
@@ -117,21 +117,6 @@ func TestCall(t *testing.T) {
 	}
 }
 
-func TestRestoreDefaults(t *testing.T) {
-	Execute(nil, nil, &Config{Debug: true})
-	if vm.ForceJit {
-		t.Error("expected force jit to be disabled")
-	}
-
-	if vm.Debug {
-		t.Error("expected debug to be disabled")
-	}
-
-	if vm.EnableJit {
-		t.Error("expected jit to be disabled")
-	}
-}
-
 func BenchmarkCall(b *testing.B) {
 	var definition = `[{"constant":true,"inputs":[],"name":"seller","outputs":[{"name":"","type":"address"}],"type":"function"},{"constant":false,"inputs":[],"name":"abort","outputs":[],"type":"function"},{"constant":true,"inputs":[],"name":"value","outputs":[{"name":"","type":"uint256"}],"type":"function"},{"constant":false,"inputs":[],"name":"refund","outputs":[],"type":"function"},{"constant":true,"inputs":[],"name":"buyer","outputs":[{"name":"","type":"address"}],"type":"function"},{"constant":false,"inputs":[],"name":"confirmReceived","outputs":[],"type":"function"},{"constant":true,"inputs":[],"name":"state","outputs":[{"name":"","type":"uint8"}],"type":"function"},{"constant":false,"inputs":[],"name":"confirmPurchase","outputs":[],"type":"function"},{"inputs":[],"type":"constructor"},{"anonymous":false,"inputs":[],"name":"Aborted","type":"event"},{"anonymous":false,"inputs":[],"name":"PurchaseConfirmed","type":"event"},{"anonymous":false,"inputs":[],"name":"ItemReceived","type":"event"},{"anonymous":false,"inputs":[],"name":"Refunded","type":"event"}]`
 
diff --git a/core/vm/virtual_machine.go b/core/vm/virtual_machine.go
index 9b3340bb2..629108884 100644
--- a/core/vm/virtual_machine.go
+++ b/core/vm/virtual_machine.go
@@ -18,6 +18,5 @@ package vm
 
 // VirtualMachine is an EVM interface
 type VirtualMachine interface {
-	Env() Environment
 	Run(*Contract, []byte) ([]byte, error)
 }
diff --git a/core/vm/vm.go b/core/vm/vm.go
index 26df8aef4..f72c853a2 100644
--- a/core/vm/vm.go
+++ b/core/vm/vm.go
@@ -28,24 +28,54 @@ import (
 	"github.com/ethereum/go-ethereum/params"
 )
 
-// Vm is an EVM and implements VirtualMachine
-type Vm struct {
+// Config are the configuration options for the EVM
+type Config struct {
+	Debug     bool
+	EnableJit bool
+	ForceJit  bool
+	Logger    LogConfig
+}
+
+// EVM is used to run Ethereum based contracts and will utilise the
+// passed environment to query external sources for state information.
+// The EVM will run the byte code VM or JIT VM based on the passed
+// configuration.
+type EVM struct {
 	env       Environment
 	jumpTable vmJumpTable
+	cfg       *Config
+
+	logger *Logger
 }
 
-func EVM(env Environment) *Vm {
-	return &Vm{env: env, jumpTable: newJumpTable(env.BlockNumber())}
+// New returns a new instance of the EVM.
+func New(env Environment, cfg *Config) *EVM {
+	// initialise a default config if none is present
+	if cfg == nil {
+		cfg = new(Config)
+	}
+
+	var logger *Logger
+	if cfg.Debug {
+		logger = newLogger(cfg.Logger, env)
+	}
+
+	return &EVM{
+		env:       env,
+		jumpTable: newJumpTable(env.BlockNumber()),
+		cfg:       cfg,
+		logger:    logger,
+	}
 }
 
 // Run loops and evaluates the contract's code with the given input data
-func (self *Vm) Run(contract *Contract, input []byte) (ret []byte, err error) {
-	self.env.SetDepth(self.env.Depth() + 1)
-	defer self.env.SetDepth(self.env.Depth() - 1)
+func (evm *EVM) Run(contract *Contract, input []byte) (ret []byte, err error) {
+	evm.env.SetDepth(evm.env.Depth() + 1)
+	defer evm.env.SetDepth(evm.env.Depth() - 1)
 
 	if contract.CodeAddr != nil {
 		if p := Precompiled[contract.CodeAddr.Str()]; p != nil {
-			return self.RunPrecompiled(p, input, contract)
+			return evm.RunPrecompiled(p, input, contract)
 		}
 	}
 
@@ -58,21 +88,21 @@ func (self *Vm) Run(contract *Contract, input []byte) (ret []byte, err error) {
 		codehash = crypto.Keccak256Hash(contract.Code) // codehash is used when doing jump dest caching
 		program  *Program
 	)
-	if EnableJit {
+	if evm.cfg.EnableJit {
 		// If the JIT is enabled check the status of the JIT program,
 		// if it doesn't exist compile a new program in a separate
 		// goroutine or wait for compilation to finish if the JIT is
 		// forced.
 		switch GetProgramStatus(codehash) {
 		case progReady:
-			return RunProgram(GetProgram(codehash), self.env, contract, input)
+			return RunProgram(GetProgram(codehash), evm.env, contract, input)
 		case progUnknown:
-			if ForceJit {
+			if evm.cfg.ForceJit {
 				// Create and compile program
 				program = NewProgram(contract.Code)
 				perr := CompileProgram(program)
 				if perr == nil {
-					return RunProgram(program, self.env, contract, input)
+					return RunProgram(program, evm.env, contract, input)
 				}
 				glog.V(logger.Info).Infoln("error compiling program", err)
 			} else {
@@ -95,10 +125,10 @@ func (self *Vm) Run(contract *Contract, input []byte) (ret []byte, err error) {
 		code       = contract.Code
 		instrCount = 0
 
-		op      OpCode          // current opcode
-		mem     = NewMemory()   // bound memory
-		stack   = newstack()    // local stack
-		statedb = self.env.Db() // current state
+		op      OpCode         // current opcode
+		mem     = NewMemory()  // bound memory
+		stack   = newstack()   // local stack
+		statedb = evm.env.Db() // current state
 		// For optimisation reason we're using uint64 as the program counter.
 		// It's theoretically possible to go above 2^64. The YP defines the PC to be uint256. Practically much less so feasible.
 		pc = uint64(0) // program counter
@@ -123,8 +153,8 @@ func (self *Vm) Run(contract *Contract, input []byte) (ret []byte, err error) {
 
 	// User defer pattern to check for an error and, based on the error being nil or not, use all gas and return.
 	defer func() {
-		if err != nil {
-			self.log(pc, op, contract.Gas, cost, mem, stack, contract, err)
+		if err != nil && evm.cfg.Debug {
+			evm.logger.captureState(pc, op, contract.Gas, cost, mem, stack, contract, err)
 		}
 	}()
 
@@ -143,7 +173,7 @@ func (self *Vm) Run(contract *Contract, input []byte) (ret []byte, err error) {
 					// move execution
 					fmt.Println("moved", it)
 					glog.V(logger.Info).Infoln("Moved execution to JIT")
-					return runProgram(program, pc, mem, stack, self.env, contract, input)
+					return runProgram(program, pc, mem, stack, evm.env, contract, input)
 				}
 			}
 		*/
@@ -151,7 +181,7 @@ func (self *Vm) Run(contract *Contract, input []byte) (ret []byte, err error) {
 		// Get the memory location of pc
 		op = contract.GetOp(pc)
 		// calculate the new memory size and gas price for the current executing opcode
-		newMemSize, cost, err = calculateGasAndSize(self.env, contract, caller, op, statedb, mem, stack)
+		newMemSize, cost, err = calculateGasAndSize(evm.env, contract, caller, op, statedb, mem, stack)
 		if err != nil {
 			return nil, err
 		}
@@ -165,14 +195,17 @@ func (self *Vm) Run(contract *Contract, input []byte) (ret []byte, err error) {
 		// Resize the memory calculated previously
 		mem.Resize(newMemSize.Uint64())
 		// Add a log message
-		self.log(pc, op, contract.Gas, cost, mem, stack, contract, nil)
-		if opPtr := self.jumpTable[op]; opPtr.valid {
+		if evm.cfg.Debug {
+			evm.logger.captureState(pc, op, contract.Gas, cost, mem, stack, contract, nil)
+		}
+
+		if opPtr := evm.jumpTable[op]; opPtr.valid {
 			if opPtr.fn != nil {
-				opPtr.fn(instruction{}, &pc, self.env, contract, mem, stack)
+				opPtr.fn(instruction{}, &pc, evm.env, contract, mem, stack)
 			} else {
 				switch op {
 				case PC:
-					opPc(instruction{data: new(big.Int).SetUint64(pc)}, &pc, self.env, contract, mem, stack)
+					opPc(instruction{data: new(big.Int).SetUint64(pc)}, &pc, evm.env, contract, mem, stack)
 				case JUMP:
 					if err := jump(pc, stack.pop()); err != nil {
 						return nil, err
@@ -195,7 +228,7 @@ func (self *Vm) Run(contract *Contract, input []byte) (ret []byte, err error) {
 
 					return ret, nil
 				case SUICIDE:
-					opSuicide(instruction{}, nil, self.env, contract, mem, stack)
+					opSuicide(instruction{}, nil, evm.env, contract, mem, stack)
 
 					fallthrough
 				case STOP: // Stop the contract
@@ -347,7 +380,7 @@ func calculateGasAndSize(env Environment, contract *Contract, caller ContractRef
 }
 
 // RunPrecompile runs and evaluate the output of a precompiled contract defined in contracts.go
-func (self *Vm) RunPrecompiled(p *PrecompiledAccount, input []byte, contract *Contract) (ret []byte, err error) {
+func (evm *EVM) RunPrecompiled(p *PrecompiledAccount, input []byte, contract *Contract) (ret []byte, err error) {
 	gas := p.Gas(len(input))
 	if contract.UseGas(gas) {
 		ret = p.Call(input)
@@ -357,27 +390,3 @@ func (self *Vm) RunPrecompiled(p *PrecompiledAccount, input []byte, contract *Co
 		return nil, OutOfGasError
 	}
 }
-
-// log emits a log event to the environment for each opcode encountered. This is not to be confused with the
-// LOG* opcode.
-func (self *Vm) log(pc uint64, op OpCode, gas, cost *big.Int, memory *Memory, stack *stack, contract *Contract, err error) {
-	if Debug || GenerateStructLogs {
-		mem := make([]byte, len(memory.Data()))
-		copy(mem, memory.Data())
-
-		stck := make([]*big.Int, len(stack.Data()))
-		for i, item := range stack.Data() {
-			stck[i] = new(big.Int).Set(item)
-		}
-		storage := make(map[common.Hash][]byte)
-		contract.self.EachStorage(func(k, v []byte) {
-			storage[common.BytesToHash(k)] = v
-		})
-		self.env.AddStructLog(StructLog{pc, op, new(big.Int).Set(gas), cost, mem, stck, storage, err})
-	}
-}
-
-// Environment returns the current workable state of the VM
-func (self *Vm) Env() Environment {
-	return self.env
-}
diff --git a/core/vm/vm_jit_fake.go b/core/vm/vm_jit_fake.go
index 192f3615d..b26cf1ad0 100644
--- a/core/vm/vm_jit_fake.go
+++ b/core/vm/vm_jit_fake.go
@@ -22,5 +22,5 @@ import "fmt"
 
 func NewJitVm(env Environment) VirtualMachine {
 	fmt.Printf("Warning! EVM JIT not enabled.\n")
-	return EVM(env)
+	return New(env, nil)
 }