cmd/evm, core/vm, test: refactored VM and core

* Moved `vm.Transfer` to `core` package and changed execution to call
`env.Transfer` instead of `core.Transfer` directly.
* core/vm: byte code VM moved to jump table instead of switch
* Moved `vm.Transfer` to `core` package and changed execution to call
  `env.Transfer` instead of `core.Transfer` directly.
* Byte code VM now shares the same code as the JITVM
* Renamed Context to Contract
* Changed initialiser of state transition & unexported methods
* Removed the Execution object and refactor `Call`, `CallCode` &
  `Create` in to their own functions instead of being methods.
* Removed the hard dep on the state for the VM. The VM now
  depends on a Database interface returned by the environment. In the
  process the core now depends less on the statedb by usage of the env
* Moved `Log` from package `core/state` to package `core/vm`.

39 files changed, 946 insertions, 1062 deletions

diff --git a/cmd/evm/main.go b/cmd/evm/main.go
index 243dd6266..bf24da982 100644
--- a/cmd/evm/main.go
+++ b/cmd/evm/main.go
@@ -80,12 +80,17 @@ var (
 		Name:  "sysstat",
 		Usage: "display system stats",
 	}
+	VerbosityFlag = cli.IntFlag{
+		Name:  "verbosity",
+		Usage: "sets the verbosity level",
+	}
 )
 
 func init() {
 	app = utils.NewApp("0.2", "the evm command line interface")
 	app.Flags = []cli.Flag{
 		DebugFlag,
+		VerbosityFlag,
 		ForceJitFlag,
 		DisableJitFlag,
 		SysStatFlag,
@@ -105,6 +110,7 @@ func run(ctx *cli.Context) {
 	vm.EnableJit = !ctx.GlobalBool(DisableJitFlag.Name)
 
 	glog.SetToStderr(true)
+	glog.SetV(ctx.GlobalInt(VerbosityFlag.Name))
 
 	db, _ := ethdb.NewMemDatabase()
 	statedb := state.New(common.Hash{}, db)
@@ -179,18 +185,20 @@ func NewEnv(state *state.StateDB, transactor common.Address, value *big.Int) *VM
 	}
 }
 
-func (self *VMEnv) State() *state.StateDB    { return self.state }
-func (self *VMEnv) Origin() common.Address   { return *self.transactor }
-func (self *VMEnv) BlockNumber() *big.Int    { return common.Big0 }
-func (self *VMEnv) Coinbase() common.Address { return *self.transactor }
-func (self *VMEnv) Time() *big.Int           { return self.time }
-func (self *VMEnv) Difficulty() *big.Int     { return common.Big1 }
-func (self *VMEnv) BlockHash() []byte        { return make([]byte, 32) }
-func (self *VMEnv) Value() *big.Int          { return self.value }
-func (self *VMEnv) GasLimit() *big.Int       { return big.NewInt(1000000000) }
-func (self *VMEnv) VmType() vm.Type          { return vm.StdVmTy }
-func (self *VMEnv) Depth() int               { return 0 }
-func (self *VMEnv) SetDepth(i int)           { self.depth = i }
+func (self *VMEnv) Db() vm.Database            { return self.state }
+func (self *VMEnv) MakeSnapshot() vm.Database  { return self.state.Copy() }
+func (self *VMEnv) SetSnapshot(db vm.Database) { self.state.Set(db.(*state.StateDB)) }
+func (self *VMEnv) Origin() common.Address     { return *self.transactor }
+func (self *VMEnv) BlockNumber() *big.Int      { return common.Big0 }
+func (self *VMEnv) Coinbase() common.Address   { return *self.transactor }
+func (self *VMEnv) Time() *big.Int             { return self.time }
+func (self *VMEnv) Difficulty() *big.Int       { return common.Big1 }
+func (self *VMEnv) BlockHash() []byte          { return make([]byte, 32) }
+func (self *VMEnv) Value() *big.Int            { return self.value }
+func (self *VMEnv) GasLimit() *big.Int         { return big.NewInt(1000000000) }
+func (self *VMEnv) VmType() vm.Type            { return vm.StdVmTy }
+func (self *VMEnv) Depth() int                 { return 0 }
+func (self *VMEnv) SetDepth(i int)             { self.depth = i }
 func (self *VMEnv) GetHash(n uint64) common.Hash {
 	if self.block.Number().Cmp(big.NewInt(int64(n))) == 0 {
 		return self.block.Hash()
@@ -203,34 +211,24 @@ func (self *VMEnv) AddStructLog(log vm.StructLog) {
 func (self *VMEnv) StructLogs() []vm.StructLog {
 	return self.logs
 }
-func (self *VMEnv) AddLog(log *state.Log) {
+func (self *VMEnv) AddLog(log *vm.Log) {
 	self.state.AddLog(log)
 }
-func (self *VMEnv) CanTransfer(from vm.Account, balance *big.Int) bool {
-	return from.Balance().Cmp(balance) >= 0
+func (self *VMEnv) CanTransfer(from common.Address, balance *big.Int) bool {
+	return self.state.GetBalance(from).Cmp(balance) >= 0
 }
 func (self *VMEnv) Transfer(from, to vm.Account, amount *big.Int) error {
-	return vm.Transfer(from, to, amount)
-}
-
-func (self *VMEnv) vm(addr *common.Address, data []byte, gas, price, value *big.Int) *core.Execution {
-	return core.NewExecution(self, addr, data, gas, price, value)
+	return core.Transfer(from, to, amount)
 }
 
-func (self *VMEnv) Call(caller vm.ContextRef, addr common.Address, data []byte, gas, price, value *big.Int) ([]byte, error) {
-	exe := self.vm(&addr, data, gas, price, value)
-	ret, err := exe.Call(addr, caller)
-	self.Gas = exe.Gas
-
-	return ret, err
+func (self *VMEnv) Call(caller vm.ContractRef, addr common.Address, data []byte, gas, price, value *big.Int) ([]byte, error) {
+	self.Gas = gas
+	return core.Call(self, caller, addr, data, gas, price, value)
 }
-func (self *VMEnv) CallCode(caller vm.ContextRef, addr common.Address, data []byte, gas, price, value *big.Int) ([]byte, error) {
-	a := caller.Address()
-	exe := self.vm(&a, data, gas, price, value)
-	return exe.Call(addr, caller)
+func (self *VMEnv) CallCode(caller vm.ContractRef, addr common.Address, data []byte, gas, price, value *big.Int) ([]byte, error) {
+	return core.CallCode(self, caller, addr, data, gas, price, value)
 }
 
-func (self *VMEnv) Create(caller vm.ContextRef, data []byte, gas, price, value *big.Int) ([]byte, error, vm.ContextRef) {
-	exe := self.vm(nil, data, gas, price, value)
-	return exe.Create(caller)
+func (self *VMEnv) Create(caller vm.ContractRef, data []byte, gas, price, value *big.Int) ([]byte, common.Address, error) {
+	return core.Create(self, caller, data, gas, price, value)
 }
diff --git a/core/block_processor.go b/core/block_processor.go
index 40590bdc5..40e3931ba 100644
--- a/core/block_processor.go
+++ b/core/block_processor.go
@@ -25,6 +25,7 @@ import (
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/core/state"
 	"github.com/ethereum/go-ethereum/core/types"
+	"github.com/ethereum/go-ethereum/core/vm"
 	"github.com/ethereum/go-ethereum/crypto"
 	"github.com/ethereum/go-ethereum/ethdb"
 	"github.com/ethereum/go-ethereum/event"
@@ -163,7 +164,7 @@ func (self *BlockProcessor) ApplyTransactions(gp GasPool, statedb *state.StateDB
 	return receipts, err
 }
 
-func (sm *BlockProcessor) RetryProcess(block *types.Block) (logs state.Logs, err error) {
+func (sm *BlockProcessor) RetryProcess(block *types.Block) (logs vm.Logs, err error) {
 	// Processing a blocks may never happen simultaneously
 	sm.mutex.Lock()
 	defer sm.mutex.Unlock()
@@ -188,7 +189,7 @@ func (sm *BlockProcessor) RetryProcess(block *types.Block) (logs state.Logs, err
 // Process block will attempt to process the given block's transactions and applies them
 // on top of the block's parent state (given it exists) and will return wether it was
 // successful or not.
-func (sm *BlockProcessor) Process(block *types.Block) (logs state.Logs, receipts types.Receipts, err error) {
+func (sm *BlockProcessor) Process(block *types.Block) (logs vm.Logs, receipts types.Receipts, err error) {
 	// Processing a blocks may never happen simultaneously
 	sm.mutex.Lock()
 	defer sm.mutex.Unlock()
@@ -204,7 +205,7 @@ func (sm *BlockProcessor) Process(block *types.Block) (logs state.Logs, receipts
 	return sm.processWithParent(block, parent)
 }
 
-func (sm *BlockProcessor) processWithParent(block, parent *types.Block) (logs state.Logs, receipts types.Receipts, err error) {
+func (sm *BlockProcessor) processWithParent(block, parent *types.Block) (logs vm.Logs, receipts types.Receipts, err error) {
 	// Create a new state based on the parent's root (e.g., create copy)
 	state := state.New(parent.Root(), sm.chainDb)
 	header := block.Header()
@@ -356,7 +357,7 @@ func (sm *BlockProcessor) GetBlockReceipts(bhash common.Hash) types.Receipts {
 // GetLogs returns the logs of the given block. This method is using a two step approach
 // where it tries to get it from the (updated) method which gets them from the receipts or
 // the depricated way by re-processing the block.
-func (sm *BlockProcessor) GetLogs(block *types.Block) (logs state.Logs, err error) {
+func (sm *BlockProcessor) GetLogs(block *types.Block) (logs vm.Logs, err error) {
 	receipts := GetBlockReceipts(sm.chainDb, block.Hash())
 	// coalesce logs
 	for _, receipt := range receipts {
diff --git a/core/block_processor_test.go b/core/block_processor_test.go
index 538cf4ee5..5735b8d0a 100644
--- a/core/block_processor_test.go
+++ b/core/block_processor_test.go
@@ -24,6 +24,7 @@ import (
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/core/state"
 	"github.com/ethereum/go-ethereum/core/types"
+	"github.com/ethereum/go-ethereum/core/vm"
 	"github.com/ethereum/go-ethereum/ethdb"
 	"github.com/ethereum/go-ethereum/event"
 	"github.com/ethereum/go-ethereum/pow/ezp"
@@ -69,7 +70,7 @@ func TestPutReceipt(t *testing.T) {
 	hash[0] = 2
 
 	receipt := new(types.Receipt)
-	receipt.SetLogs(state.Logs{&state.Log{
+	receipt.SetLogs(vm.Logs{&vm.Log{
 		Address:   addr,
 		Topics:    []common.Hash{hash},
 		Data:      []byte("hi"),
diff --git a/core/chain_manager_test.go b/core/chain_manager_test.go
index 6cfafb8c0..40286190b 100644
--- a/core/chain_manager_test.go
+++ b/core/chain_manager_test.go
@@ -28,8 +28,8 @@ import (
 
 	"github.com/ethereum/ethash"
 	"github.com/ethereum/go-ethereum/common"
-	"github.com/ethereum/go-ethereum/core/state"
 	"github.com/ethereum/go-ethereum/core/types"
+	"github.com/ethereum/go-ethereum/core/vm"
 	"github.com/ethereum/go-ethereum/crypto"
 	"github.com/ethereum/go-ethereum/ethdb"
 	"github.com/ethereum/go-ethereum/event"
@@ -361,7 +361,7 @@ func TestChainMultipleInsertions(t *testing.T) {
 
 type bproc struct{}
 
-func (bproc) Process(*types.Block) (state.Logs, types.Receipts, error) { return nil, nil, nil }
+func (bproc) Process(*types.Block) (vm.Logs, types.Receipts, error) { return nil, nil, nil }
 
 func makeChainWithDiff(genesis *types.Block, d []int, seed byte) []*types.Block {
 	var chain []*types.Block
diff --git a/core/events.go b/core/events.go
index e142b6dba..8cf230dda 100644
--- a/core/events.go
+++ b/core/events.go
@@ -20,8 +20,8 @@ import (
 	"math/big"
 
 	"github.com/ethereum/go-ethereum/common"
-	"github.com/ethereum/go-ethereum/core/state"
 	"github.com/ethereum/go-ethereum/core/types"
+	"github.com/ethereum/go-ethereum/core/vm"
 )
 
 // TxPreEvent is posted when a transaction enters the transaction pool.
@@ -42,23 +42,23 @@ type RemovedTransactionEvent struct{ Txs types.Transactions }
 // ChainSplit is posted when a new head is detected
 type ChainSplitEvent struct {
 	Block *types.Block
-	Logs  state.Logs
+	Logs  vm.Logs
 }
 
 type ChainEvent struct {
 	Block *types.Block
 	Hash  common.Hash
-	Logs  state.Logs
+	Logs  vm.Logs
 }
 
 type ChainSideEvent struct {
 	Block *types.Block
-	Logs  state.Logs
+	Logs  vm.Logs
 }
 
 type PendingBlockEvent struct {
 	Block *types.Block
-	Logs  state.Logs
+	Logs  vm.Logs
 }
 
 type ChainUncleEvent struct {
diff --git a/core/execution.go b/core/execution.go
index 3a136515d..e3c00a2ea 100644
--- a/core/execution.go
+++ b/core/execution.go
@@ -17,108 +17,104 @@
 package core
 
 import (
+	"errors"
 	"math/big"
 
 	"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/params"
 )
 
-// Execution is the execution environment for the given call or create action.
-type Execution struct {
-	env     vm.Environment
-	address *common.Address
-	input   []byte
-	evm     vm.VirtualMachine
-
-	Gas, price, value *big.Int
+// Call executes within the given contract
+func Call(env vm.Environment, caller vm.ContractRef, addr common.Address, input []byte, gas, gasPrice, value *big.Int) (ret []byte, err error) {
+	ret, _, err = exec(env, caller, &addr, &addr, input, env.Db().GetCode(addr), gas, gasPrice, value)
+	return ret, err
 }
 
-// NewExecution returns a new execution environment that handles all calling
-// and creation logic defined by the YP.
-func NewExecution(env vm.Environment, address *common.Address, input []byte, gas, gasPrice, value *big.Int) *Execution {
-	exe := &Execution{env: env, address: address, input: input, Gas: gas, price: gasPrice, value: value}
-	exe.evm = vm.NewVm(env)
-	return exe
+// CallCode executes the given address' code as the given contract address
+func CallCode(env vm.Environment, caller vm.ContractRef, addr common.Address, input []byte, gas, gasPrice, value *big.Int) (ret []byte, err error) {
+	prev := caller.Address()
+	ret, _, err = exec(env, caller, &prev, &addr, input, env.Db().GetCode(addr), gas, gasPrice, value)
+	return ret, err
 }
 
-// Call executes within the given context
-func (self *Execution) Call(codeAddr common.Address, caller vm.ContextRef) ([]byte, error) {
-	// Retrieve the executing code
-	code := self.env.State().GetCode(codeAddr)
-
-	return self.exec(&codeAddr, code, caller)
-}
-
-// Create creates a new contract and runs the initialisation procedure of the
-// contract. This returns the returned code for the contract and is stored
-// elsewhere.
-func (self *Execution) Create(caller vm.ContextRef) (ret []byte, err error, account *state.StateObject) {
-	// Input must be nil for create
-	code := self.input
-	self.input = nil
-	ret, err = self.exec(nil, code, caller)
+// Create creates a new contract with the given code
+func Create(env vm.Environment, caller vm.ContractRef, code []byte, gas, gasPrice, value *big.Int) (ret []byte, address common.Address, err error) {
+	ret, address, err = exec(env, caller, nil, nil, nil, code, gas, gasPrice, value)
 	// Here we get an error if we run into maximum stack depth,
 	// See: https://github.com/ethereum/yellowpaper/pull/131
 	// and YP definitions for CREATE instruction
 	if err != nil {
-		return nil, err, nil
+		return nil, address, err
 	}
-	account = self.env.State().GetStateObject(*self.address)
-	return
+	return ret, address, err
 }
 
-// exec executes the given code and executes within the contextAddr context.
-func (self *Execution) exec(contextAddr *common.Address, code []byte, caller vm.ContextRef) (ret []byte, err error) {
-	env := self.env
-	evm := self.evm
+func exec(env vm.Environment, caller vm.ContractRef, address, codeAddr *common.Address, input, code []byte, gas, gasPrice, value *big.Int) (ret []byte, addr common.Address, err error) {
+	evm := vm.NewVm(env)
+
 	// Depth check execution. Fail if we're trying to execute above the
 	// limit.
 	if env.Depth() > int(params.CallCreateDepth.Int64()) {
-		caller.ReturnGas(self.Gas, self.price)
+		caller.ReturnGas(gas, gasPrice)
 
-		return nil, vm.DepthError
+		return nil, common.Address{}, vm.DepthError
 	}
 
-	if !env.CanTransfer(env.State().GetStateObject(caller.Address()), self.value) {
-		caller.ReturnGas(self.Gas, self.price)
+	if !env.CanTransfer(caller.Address(), value) {
+		caller.ReturnGas(gas, gasPrice)
 
-		return nil, ValueTransferErr("insufficient funds to transfer value. Req %v, has %v", self.value, env.State().GetBalance(caller.Address()))
+		return nil, common.Address{}, ValueTransferErr("insufficient funds to transfer value. Req %v, has %v", value, env.Db().GetBalance(caller.Address()))
 	}
 
 	var createAccount bool
-	if self.address == nil {
+	if address == nil {
 		// Generate a new address
-		nonce := env.State().GetNonce(caller.Address())
-		env.State().SetNonce(caller.Address(), nonce+1)
+		nonce := env.Db().GetNonce(caller.Address())
+		env.Db().SetNonce(caller.Address(), nonce+1)
 
-		addr := crypto.CreateAddress(caller.Address(), nonce)
+		addr = crypto.CreateAddress(caller.Address(), nonce)
 
-		self.address = &addr
+		address = &addr
 		createAccount = true
 	}
-	snapshot := env.State().Copy()
+	snapshot := env.MakeSnapshot()
 
 	var (
-		from = env.State().GetStateObject(caller.Address())
-		to   *state.StateObject
+		from = env.Db().GetAccount(caller.Address())
+		to   vm.Account
 	)
 	if createAccount {
-		to = env.State().CreateAccount(*self.address)
+		to = env.Db().CreateAccount(*address)
 	} else {
-		to = env.State().GetOrNewStateObject(*self.address)
+		if !env.Db().Exist(*address) {
+			to = env.Db().CreateAccount(*address)
+		} else {
+			to = env.Db().GetAccount(*address)
+		}
 	}
-	vm.Transfer(from, to, self.value)
+	env.Transfer(from, to, value)
 
-	context := vm.NewContext(caller, to, self.value, self.Gas, self.price)
-	context.SetCallCode(contextAddr, code)
+	contract := vm.NewContract(caller, to, value, gas, gasPrice)
+	contract.SetCallCode(codeAddr, code)
 
-	ret, err = evm.Run(context, self.input)
+	ret, err = evm.Run(contract, input)
 	if err != nil {
-		env.State().Set(snapshot)
+		env.SetSnapshot(snapshot) //env.Db().Set(snapshot)
 	}
 
-	return
+	return ret, addr, err
+}
+
+// generic transfer method
+func Transfer(from, to vm.Account, amount *big.Int) error {
+	if from.Balance().Cmp(amount) < 0 {
+		return errors.New("Insufficient balance in account")
+	}
+
+	from.SubBalance(amount)
+	to.AddBalance(amount)
+
+	return nil
 }
diff --git a/core/state/statedb.go b/core/state/statedb.go
index 4233c763b..499ea5f52 100644
--- a/core/state/statedb.go
+++ b/core/state/statedb.go
@@ -21,6 +21,7 @@ import (
 	"math/big"
 
 	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/core/vm"
 	"github.com/ethereum/go-ethereum/ethdb"
 	"github.com/ethereum/go-ethereum/logger"
 	"github.com/ethereum/go-ethereum/logger/glog"
@@ -42,7 +43,7 @@ type StateDB struct {
 
 	thash, bhash common.Hash
 	txIndex      int
-	logs         map[common.Hash]Logs
+	logs         map[common.Hash]vm.Logs
 	logSize      uint
 }
 
@@ -59,7 +60,7 @@ func New(root common.Hash, db ethdb.Database) *StateDB {
 		trie:         tr,
 		stateObjects: make(map[string]*StateObject),
 		refund:       new(big.Int),
-		logs:         make(map[common.Hash]Logs),
+		logs:         make(map[common.Hash]vm.Logs),
 	}
 }
 
@@ -69,7 +70,7 @@ func (self *StateDB) StartRecord(thash, bhash common.Hash, ti int) {
 	self.txIndex = ti
 }
 
-func (self *StateDB) AddLog(log *Log) {
+func (self *StateDB) AddLog(log *vm.Log) {
 	log.TxHash = self.thash
 	log.BlockHash = self.bhash
 	log.TxIndex = uint(self.txIndex)
@@ -78,30 +79,34 @@ func (self *StateDB) AddLog(log *Log) {
 	self.logSize++
 }
 
-func (self *StateDB) GetLogs(hash common.Hash) Logs {
+func (self *StateDB) GetLogs(hash common.Hash) vm.Logs {
 	return self.logs[hash]
 }
 
-func (self *StateDB) Logs() Logs {
-	var logs Logs
+func (self *StateDB) Logs() vm.Logs {
+	var logs vm.Logs
 	for _, lgs := range self.logs {
 		logs = append(logs, lgs...)
 	}
 	return logs
 }
 
-func (self *StateDB) Refund(gas *big.Int) {
+func (self *StateDB) AddRefund(gas *big.Int) {
 	self.refund.Add(self.refund, gas)
 }
 
-/*
- * GETTERS
- */
-
 func (self *StateDB) HasAccount(addr common.Address) bool {
 	return self.GetStateObject(addr) != nil
 }
 
+func (self *StateDB) Exist(addr common.Address) bool {
+	return self.GetStateObject(addr) != nil
+}
+
+func (self *StateDB) GetAccount(addr common.Address) vm.Account {
+	return self.GetStateObject(addr)
+}
+
 // Retrieve the balance from the given address or 0 if object not found
 func (self *StateDB) GetBalance(addr common.Address) *big.Int {
 	stateObject := self.GetStateObject(addr)
@@ -245,7 +250,7 @@ func (self *StateDB) SetStateObject(object *StateObject) {
 func (self *StateDB) GetOrNewStateObject(addr common.Address) *StateObject {
 	stateObject := self.GetStateObject(addr)
 	if stateObject == nil || stateObject.deleted {
-		stateObject = self.CreateAccount(addr)
+		stateObject = self.CreateStateObject(addr)
 	}
 
 	return stateObject
@@ -264,7 +269,7 @@ func (self *StateDB) newStateObject(addr common.Address) *StateObject {
 }
 
 // Creates creates a new state object and takes ownership. This is different from "NewStateObject"
-func (self *StateDB) CreateAccount(addr common.Address) *StateObject {
+func (self *StateDB) CreateStateObject(addr common.Address) *StateObject {
 	// Get previous (if any)
 	so := self.GetStateObject(addr)
 	// Create a new one
@@ -278,6 +283,10 @@ func (self *StateDB) CreateAccount(addr common.Address) *StateObject {
 	return newSo
 }
 
+func (self *StateDB) CreateAccount(addr common.Address) vm.Account {
+	return self.CreateStateObject(addr)
+}
+
 //
 // Setting, copying of the state methods
 //
@@ -292,7 +301,7 @@ func (self *StateDB) Copy() *StateDB {
 	state.refund.Set(self.refund)
 
 	for hash, logs := range self.logs {
-		state.logs[hash] = make(Logs, len(logs))
+		state.logs[hash] = make(vm.Logs, len(logs))
 		copy(state.logs[hash], logs)
 	}
 	state.logSize = self.logSize
@@ -309,6 +318,10 @@ func (self *StateDB) Set(state *StateDB) {
 	self.logSize = state.logSize
 }
 
+func (self *StateDB) GetRefund() *big.Int {
+	return self.refund
+}
+
 // IntermediateRoot computes the current root hash of the state trie.
 // It is called in between transactions to get the root hash that
 // goes into transaction receipts.
diff --git a/core/state_transition.go b/core/state_transition.go
index 6ff7fa1ff..e83019229 100644
--- a/core/state_transition.go
+++ b/core/state_transition.go
@@ -51,7 +51,7 @@ type StateTransition struct {
 	initialGas    *big.Int
 	value         *big.Int
 	data          []byte
-	state         *state.StateDB
+	state         vm.Database
 
 	env vm.Environment
 }
@@ -95,11 +95,7 @@ func IntrinsicGas(data []byte) *big.Int {
 }
 
 func ApplyMessage(env vm.Environment, msg Message, gp GasPool) ([]byte, *big.Int, error) {
-	return NewStateTransition(env, msg, gp).transitionState()
-}
-
-func NewStateTransition(env vm.Environment, msg Message, gp GasPool) *StateTransition {
-	return &StateTransition{
+	var st = StateTransition{
 		gp:         gp,
 		env:        env,
 		msg:        msg,
@@ -108,18 +104,22 @@ func NewStateTransition(env vm.Environment, msg Message, gp GasPool) *StateTrans
 		initialGas: new(big.Int),
 		value:      msg.Value(),
 		data:       msg.Data(),
-		state:      env.State(),
+		state:      env.Db(),
 	}
+	return st.transitionDb()
 }
 
-func (self *StateTransition) From() (*state.StateObject, error) {
+func (self *StateTransition) from() (vm.Account, error) {
 	f, err := self.msg.From()
 	if err != nil {
 		return nil, err
 	}
-	return self.state.GetOrNewStateObject(f), nil
+	if !self.state.Exist(f) {
+		return self.state.CreateAccount(f), nil
+	}
+	return self.state.GetAccount(f), nil
 }
-func (self *StateTransition) To() *state.StateObject {
+func (self *StateTransition) to() vm.Account {
 	if self.msg == nil {
 		return nil
 	}
@@ -127,10 +127,14 @@ func (self *StateTransition) To() *state.StateObject {
 	if to == nil {
 		return nil // contract creation
 	}
-	return self.state.GetOrNewStateObject(*to)
+
+	if !self.state.Exist(*to) {
+		return self.state.CreateAccount(*to)
+	}
+	return self.state.GetAccount(*to)
 }
 
-func (self *StateTransition) UseGas(amount *big.Int) error {
+func (self *StateTransition) useGas(amount *big.Int) error {
 	if self.gas.Cmp(amount) < 0 {
 		return vm.OutOfGasError
 	}
@@ -139,15 +143,15 @@ func (self *StateTransition) UseGas(amount *big.Int) error {
 	return nil
 }
 
-func (self *StateTransition) AddGas(amount *big.Int) {
+func (self *StateTransition) addGas(amount *big.Int) {
 	self.gas.Add(self.gas, amount)
 }
 
-func (self *StateTransition) BuyGas() error {
+func (self *StateTransition) buyGas() error {
 	mgas := self.msg.Gas()
 	mgval := new(big.Int).Mul(mgas, self.gasPrice)
 
-	sender, err := self.From()
+	sender, err := self.from()
 	if err != nil {
 		return err
 	}
@@ -157,7 +161,7 @@ func (self *StateTransition) BuyGas() error {
 	if err = self.gp.SubGas(mgas, self.gasPrice); err != nil {
 		return err
 	}
-	self.AddGas(mgas)
+	self.addGas(mgas)
 	self.initialGas.Set(mgas)
 	sender.SubBalance(mgval)
 	return nil
@@ -165,18 +169,19 @@ func (self *StateTransition) BuyGas() error {
 
 func (self *StateTransition) preCheck() (err error) {
 	msg := self.msg
-	sender, err := self.From()
+	sender, err := self.from()
 	if err != nil {
 		return err
 	}
 
 	// Make sure this transaction's nonce is correct
-	if sender.Nonce() != msg.Nonce() {
-		return NonceError(msg.Nonce(), sender.Nonce())
+	//if sender.Nonce() != msg.Nonce() {
+	if n := self.state.GetNonce(sender.Address()); n != msg.Nonce() {
+		return NonceError(msg.Nonce(), n)
 	}
 
 	// Pre-pay gas / Buy gas of the coinbase account
-	if err = self.BuyGas(); err != nil {
+	if err = self.buyGas(); err != nil {
 		if state.IsGasLimitErr(err) {
 			return err
 		}
@@ -186,28 +191,28 @@ func (self *StateTransition) preCheck() (err error) {
 	return nil
 }
 
-func (self *StateTransition) transitionState() (ret []byte, usedGas *big.Int, err error) {
+func (self *StateTransition) transitionDb() (ret []byte, usedGas *big.Int, err error) {
 	if err = self.preCheck(); err != nil {
 		return
 	}
 
 	msg := self.msg
-	sender, _ := self.From() // err checked in preCheck
+	sender, _ := self.from() // err checked in preCheck
 
 	// Pay intrinsic gas
-	if err = self.UseGas(IntrinsicGas(self.data)); err != nil {
+	if err = self.useGas(IntrinsicGas(self.data)); err != nil {
 		return nil, nil, InvalidTxError(err)
 	}
 
 	vmenv := self.env
-	var ref vm.ContextRef
+	var addr common.Address
 	if MessageCreatesContract(msg) {
-		ret, err, ref = vmenv.Create(sender, self.data, self.gas, self.gasPrice, self.value)
+		ret, addr, err = vmenv.Create(sender, self.data, self.gas, self.gasPrice, self.value)
 		if err == nil {
 			dataGas := big.NewInt(int64(len(ret)))
 			dataGas.Mul(dataGas, params.CreateDataGas)
-			if err := self.UseGas(dataGas); err == nil {
-				ref.SetCode(ret)
+			if err := self.useGas(dataGas); err == nil {
+				self.state.SetCode(addr, ret)
 			} else {
 				ret = nil // does not affect consensus but useful for StateTests validations
 				glog.V(logger.Core).Infoln("Insufficient gas for creating code. Require", dataGas, "and have", self.gas)
@@ -216,8 +221,8 @@ func (self *StateTransition) transitionState() (ret []byte, usedGas *big.Int, er
 		glog.V(logger.Core).Infoln("VM create err:", err)
 	} else {
 		// Increment the nonce for the next transaction
-		self.state.SetNonce(sender.Address(), sender.Nonce()+1)
-		ret, err = vmenv.Call(sender, self.To().Address(), self.data, self.gas, self.gasPrice, self.value)
+		self.state.SetNonce(sender.Address(), self.state.GetNonce(sender.Address())+1)
+		ret, err = vmenv.Call(sender, self.to().Address(), self.data, self.gas, self.gasPrice, self.value)
 		glog.V(logger.Core).Infoln("VM call err:", err)
 	}
 
@@ -241,13 +246,13 @@ func (self *StateTransition) transitionState() (ret []byte, usedGas *big.Int, er
 }
 
 func (self *StateTransition) refundGas() {
-	sender, _ := self.From() // err already checked
+	sender, _ := self.from() // err already checked
 	// Return remaining gas
 	remaining := new(big.Int).Mul(self.gas, self.gasPrice)
 	sender.AddBalance(remaining)
 
 	uhalf := remaining.Div(self.gasUsed(), common.Big2)
-	refund := common.BigMin(uhalf, self.state.Refunds())
+	refund := common.BigMin(uhalf, self.state.GetRefund())
 	self.gas.Add(self.gas, refund)
 	self.state.AddBalance(sender.Address(), refund.Mul(refund, self.gasPrice))
 
diff --git a/core/types/bloom9.go b/core/types/bloom9.go
index 0629b31d4..f87ae58e6 100644
--- a/core/types/bloom9.go
+++ b/core/types/bloom9.go
@@ -20,7 +20,7 @@ import (
 	"math/big"
 
 	"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"
 )
 
@@ -37,7 +37,7 @@ func CreateBloom(receipts Receipts) Bloom {
 	return BytesToBloom(bin.Bytes())
 }
 
-func LogsBloom(logs state.Logs) *big.Int {
+func LogsBloom(logs vm.Logs) *big.Int {
 	bin := new(big.Int)
 	for _, log := range logs {
 		data := make([]common.Hash, len(log.Topics))
diff --git a/core/types/common.go b/core/types/common.go
index de6efcd86..dc428c00c 100644
--- a/core/types/common.go
+++ b/core/types/common.go
@@ -19,14 +19,14 @@ package types
 import (
 	"math/big"
 
-	"github.com/ethereum/go-ethereum/common"
-	"github.com/ethereum/go-ethereum/core/state"
-
 	"fmt"
+
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/core/vm"
 )
 
 type BlockProcessor interface {
-	Process(*Block) (state.Logs, Receipts, error)
+	Process(*Block) (vm.Logs, Receipts, error)
 }
 
 const bloomLength = 256
diff --git a/core/types/receipt.go b/core/types/receipt.go
index e01d69005..bcb4bd8a5 100644
--- a/core/types/receipt.go
+++ b/core/types/receipt.go
@@ -23,7 +23,7 @@ import (
 	"math/big"
 
 	"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/rlp"
 )
 
@@ -33,7 +33,7 @@ type Receipt struct {
 	Bloom             Bloom
 	TxHash            common.Hash
 	ContractAddress   common.Address
-	logs              state.Logs
+	logs              vm.Logs
 	GasUsed           *big.Int
 }
 
@@ -41,11 +41,11 @@ func NewReceipt(root []byte, cumalativeGasUsed *big.Int) *Receipt {
 	return &Receipt{PostState: common.CopyBytes(root), CumulativeGasUsed: new(big.Int).Set(cumalativeGasUsed)}
 }
 
-func (self *Receipt) SetLogs(logs state.Logs) {
+func (self *Receipt) SetLogs(logs vm.Logs) {
 	self.logs = logs
 }
 
-func (self *Receipt) Logs() state.Logs {
+func (self *Receipt) Logs() vm.Logs {
 	return self.logs
 }
 
@@ -60,7 +60,7 @@ func (self *Receipt) DecodeRLP(s *rlp.Stream) error {
 		Bloom             Bloom
 		TxHash            common.Hash
 		ContractAddress   common.Address
-		Logs              state.Logs
+		Logs              vm.Logs
 		GasUsed           *big.Int
 	}
 	if err := s.Decode(&r); err != nil {
@@ -74,9 +74,9 @@ func (self *Receipt) DecodeRLP(s *rlp.Stream) error {
 type ReceiptForStorage Receipt
 
 func (self *ReceiptForStorage) EncodeRLP(w io.Writer) error {
-	storageLogs := make([]*state.LogForStorage, len(self.logs))
+	storageLogs := make([]*vm.LogForStorage, len(self.logs))
 	for i, log := range self.logs {
-		storageLogs[i] = (*state.LogForStorage)(log)
+		storageLogs[i] = (*vm.LogForStorage)(log)
 	}
 	return rlp.Encode(w, []interface{}{self.PostState, self.CumulativeGasUsed, self.Bloom, self.TxHash, self.ContractAddress, storageLogs, self.GasUsed})
 }
diff --git a/core/vm/asm.go b/core/vm/asm.go
index 639201e50..065d3eb97 100644
--- a/core/vm/asm.go
+++ b/core/vm/asm.go
@@ -23,6 +23,8 @@ import (
 	"github.com/ethereum/go-ethereum/common"
 )
 
+// Dissassemble dissassembles the byte code and returns the string
+// representation (human readable opcodes).
 func Disassemble(script []byte) (asm []string) {
 	pc := new(big.Int)
 	for {
diff --git a/core/vm/common.go b/core/vm/common.go
index 2e03ec80b..b52b598ba 100644
--- a/core/vm/common.go
+++ b/core/vm/common.go
@@ -22,34 +22,34 @@ import (
 
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/logger/glog"
+	"github.com/ethereum/go-ethereum/params"
 )
 
 // Global Debug flag indicating Debug VM (full logging)
 var Debug bool
 
+// Type is the VM type accepted by **NewVm**
 type Type byte
 
 const (
-	StdVmTy Type = iota
-	JitVmTy
+	StdVmTy Type = iota // Default standard VM
+	JitVmTy             // LLVM JIT VM
 	MaxVmTy
-
-	LogTyPretty byte = 0x1
-	LogTyDiff   byte = 0x2
 )
 
 var (
-	Pow256 = common.BigPow(2, 256)
+	Pow256 = common.BigPow(2, 256) // Pew256 is 2**256
 
-	U256 = common.U256
-	S256 = common.S256
+	U256 = common.U256 // Shortcut to common.U256
+	S256 = common.S256 // Shortcut to common.S256
 
-	Zero = common.Big0
-	One  = common.Big1
+	Zero = common.Big0 // Shortcut to common.Big0
+	One  = common.Big1 // Shortcut to common.Big1
 
-	max = big.NewInt(math.MaxInt64)
+	max = big.NewInt(math.MaxInt64) // Maximum 256 bit integer
 )
 
+// NewVm returns a new VM based on the Environment
 func NewVm(env Environment) VirtualMachine {
 	switch env.VmType() {
 	case JitVmTy:
@@ -62,6 +62,7 @@ func NewVm(env Environment) VirtualMachine {
 	}
 }
 
+// calculates the memory size required for a step
 func calcMemSize(off, l *big.Int) *big.Int {
 	if l.Cmp(common.Big0) == 0 {
 		return common.Big0
@@ -70,6 +71,32 @@ func calcMemSize(off, l *big.Int) *big.Int {
 	return new(big.Int).Add(off, l)
 }
 
+// calculates the quadratic gas
+func quadMemGas(mem *Memory, newMemSize, gas *big.Int) {
+	if newMemSize.Cmp(common.Big0) > 0 {
+		newMemSizeWords := toWordSize(newMemSize)
+		newMemSize.Mul(newMemSizeWords, u256(32))
+
+		if newMemSize.Cmp(u256(int64(mem.Len()))) > 0 {
+			// be careful reusing variables here when changing.
+			// The order has been optimised to reduce allocation
+			oldSize := toWordSize(big.NewInt(int64(mem.Len())))
+			pow := new(big.Int).Exp(oldSize, common.Big2, Zero)
+			linCoef := oldSize.Mul(oldSize, params.MemoryGas)
+			quadCoef := new(big.Int).Div(pow, params.QuadCoeffDiv)
+			oldTotalFee := new(big.Int).Add(linCoef, quadCoef)
+
+			pow.Exp(newMemSizeWords, common.Big2, Zero)
+			linCoef = linCoef.Mul(newMemSizeWords, params.MemoryGas)
+			quadCoef = quadCoef.Div(pow, params.QuadCoeffDiv)
+			newTotalFee := linCoef.Add(linCoef, quadCoef)
+
+			fee := newTotalFee.Sub(newTotalFee, oldTotalFee)
+			gas.Add(gas, fee)
+		}
+	}
+}
+
 // Simple helper
 func u256(n int64) *big.Int {
 	return big.NewInt(n)
@@ -86,6 +113,8 @@ func toValue(val *big.Int) interface{} {
 	return val
 }
 
+// getData 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 getData(data []byte, start, size *big.Int) []byte {
 	dlen := big.NewInt(int64(len(data)))
 
@@ -94,7 +123,9 @@ func getData(data []byte, start, size *big.Int) []byte {
 	return common.RightPadBytes(data[s.Uint64():e.Uint64()], int(size.Uint64()))
 }
 
-func UseGas(gas, amount *big.Int) bool {
+// useGas attempts to subtract the amount of gas and returns whether it was
+// successful
+func useGas(gas, amount *big.Int) bool {
 	if gas.Cmp(amount) < 0 {
 		return false
 	}
diff --git a/core/vm/context.go b/core/vm/contract.go
index d17934ba5..8460cc47b 100644
--- a/core/vm/context.go
+++ b/core/vm/contract.go
@@ -22,15 +22,18 @@ import (
 	"github.com/ethereum/go-ethereum/common"
 )
 
-type ContextRef interface {
+// ContractRef is a reference to the contract's backing object
+type ContractRef interface {
 	ReturnGas(*big.Int, *big.Int)
 	Address() common.Address
 	SetCode([]byte)
 }
 
-type Context struct {
-	caller ContextRef
-	self   ContextRef
+// Contract represents an ethereum contract in the state database. It contains
+// the the contract code, calling arguments. Contract implements ContractReg
+type Contract struct {
+	caller ContractRef
+	self   ContractRef
 
 	jumpdests destinations // result of JUMPDEST analysis.
 
@@ -44,10 +47,10 @@ type Context struct {
 }
 
 // Create a new context for the given data items.
-func NewContext(caller ContextRef, object ContextRef, value, gas, price *big.Int) *Context {
-	c := &Context{caller: caller, self: object, Args: nil}
+func NewContract(caller ContractRef, object ContractRef, value, gas, price *big.Int) *Contract {
+	c := &Contract{caller: caller, self: object, Args: nil}
 
-	if parent, ok := caller.(*Context); ok {
+	if parent, ok := caller.(*Contract); ok {
 		// Reuse JUMPDEST analysis from parent context if available.
 		c.jumpdests = parent.jumpdests
 	} else {
@@ -66,11 +69,13 @@ func NewContext(caller ContextRef, object ContextRef, value, gas, price *big.Int
 	return c
 }
 
-func (c *Context) GetOp(n uint64) OpCode {
+// GetOp returns the n'th element in the contract's byte array
+func (c *Contract) GetOp(n uint64) OpCode {
 	return OpCode(c.GetByte(n))
 }
 
-func (c *Context) GetByte(n uint64) byte {
+// GetByte returns the n'th byte in the contract's byte array
+func (c *Contract) GetByte(n uint64) byte {
 	if n < uint64(len(c.Code)) {
 		return c.Code[n]
 	}
@@ -78,43 +83,44 @@ func (c *Context) GetByte(n uint64) byte {
 	return 0
 }
 
-func (c *Context) Return(ret []byte) []byte {
+// Return returns the given ret argument and returns any remaining gas to the
+// caller
+func (c *Contract) Return(ret []byte) []byte {
 	// Return the remaining gas to the caller
 	c.caller.ReturnGas(c.Gas, c.Price)
 
 	return ret
 }
 
-/*
- * Gas functions
- */
-func (c *Context) UseGas(gas *big.Int) (ok bool) {
-	ok = UseGas(c.Gas, gas)
+// UseGas attempts the use gas and subtracts it and returns true on success
+func (c *Contract) UseGas(gas *big.Int) (ok bool) {
+	ok = useGas(c.Gas, gas)
 	if ok {
 		c.UsedGas.Add(c.UsedGas, gas)
 	}
 	return
 }
 
-// Implement the caller interface
-func (c *Context) ReturnGas(gas, price *big.Int) {
+// ReturnGas adds the given gas back to itself.
+func (c *Contract) ReturnGas(gas, price *big.Int) {
 	// Return the gas to the context
 	c.Gas.Add(c.Gas, gas)
 	c.UsedGas.Sub(c.UsedGas, gas)
 }
 
-/*
- * Set / Get
- */
-func (c *Context) Address() common.Address {
+// Address returns the contracts address
+func (c *Contract) Address() common.Address {
 	return c.self.Address()
 }
 
-func (self *Context) SetCode(code []byte) {
+// SetCode sets the code to the contract
+func (self *Contract) SetCode(code []byte) {
 	self.Code = code
 }
 
-func (self *Context) SetCallCode(addr *common.Address, code []byte) {
+// SetCallCode sets the address of the code address and sets the code
+// of the contract according to the backing database.
+func (self *Contract) SetCallCode(addr *common.Address, code []byte) {
 	self.Code = code
 	self.CodeAddr = addr
 }
diff --git a/core/vm/contracts.go b/core/vm/contracts.go
index b965fa095..22cb9eab2 100644
--- a/core/vm/contracts.go
+++ b/core/vm/contracts.go
@@ -26,22 +26,22 @@ import (
 	"github.com/ethereum/go-ethereum/params"
 )
 
-type Address interface {
-	Call(in []byte) []byte
-}
-
+// PrecompiledAccount represents a native ethereum contract
 type PrecompiledAccount struct {
 	Gas func(l int) *big.Int
 	fn  func(in []byte) []byte
 }
 
+// Call calls the native function
 func (self PrecompiledAccount) Call(in []byte) []byte {
 	return self.fn(in)
 }
 
+// Precompiled contains the default set of ethereum contracts
 var Precompiled = PrecompiledContracts()
 
-// XXX Could set directly. Testing requires resetting and setting of pre compiled contracts.
+// PrecompiledContracts returns the default set of precompiled ethereum
+// contracts defined by the ethereum yellow paper.
 func PrecompiledContracts() map[string]*PrecompiledAccount {
 	return map[string]*PrecompiledAccount{
 		// ECRECOVER
diff --git a/core/vm/settings.go b/core/vm/doc.go
index f9296f6c8..4deb7761d 100644
--- a/core/vm/settings.go
+++ b/core/vm/doc.go
@@ -14,12 +14,19 @@
 // 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
+/*
+Package vm implements the Ethereum Virtual Machine.
 
-var (
-	EnableJit   bool // Enables the JIT VM
-	ForceJit    bool // Force the JIT, skip byte VM
-	MaxProgSize int  // Max cache size for JIT Programs
-)
+The vm package implements two EVMs, a byte code VM and a JIT VM. The BC
+(Byte Code) VM loops over a set of bytes and executes them according to a set
+of rules defined in the Ethereum yellow paper. When the BC VM is invokes it
+invokes the JIT VM in a seperate goroutine and compiles the byte code in JIT
+instructions.
 
-const defaultJitMaxCache int = 64
+The JIT VM, when invoked, loops around a set of pre-defined instructions until
+it either runs of gas, causes an internel error, returns or stops. At a later
+stage the JIT VM will see some additional features that will cause sets of
+instructions to be compiled down to segments. Segments are sets of instructions
+that can be ran in one go saving precious time during execution.
+*/
+package vm
diff --git a/core/vm/environment.go b/core/vm/environment.go
index 916081f51..606518fd4 100644
--- a/core/vm/environment.go
+++ b/core/vm/environment.go
@@ -17,39 +17,86 @@
 package vm
 
 import (
-	"errors"
 	"math/big"
 
 	"github.com/ethereum/go-ethereum/common"
-	"github.com/ethereum/go-ethereum/core/state"
 )
 
 // Environment is is required by the virtual machine to get information from
-// it's own isolated environment. For an example see `core.VMEnv`
-type Environment interface {
-	State() *state.StateDB
+// it's own isolated environment.
 
+// Environment is an EVM requirement and helper which allows access to outside
+// information such like states.
+type Environment interface {
+	// The state database
+	Db() Database
+	// Creates a restorable snapshot
+	MakeSnapshot() Database
+	// Set database to previous snapshot
+	SetSnapshot(Database)
+	// Address of the original invoker (first occurance of the VM invoker)
 	Origin() common.Address
+	// The block number this VM is invoken on
 	BlockNumber() *big.Int
+	// The n'th hash ago from this block number
 	GetHash(n uint64) common.Hash
+	// The handler's address
 	Coinbase() common.Address
+	// The current time (block time)
 	Time() *big.Int
+	// Difficulty set on the current block
 	Difficulty() *big.Int
+	// The gas limit of the block
 	GasLimit() *big.Int
-	CanTransfer(from Account, balance *big.Int) bool
+	// Determines whether it's possible to transact
+	CanTransfer(from common.Address, balance *big.Int) bool
+	// Transfer from to to with amount set
 	Transfer(from, to Account, amount *big.Int) error
-	AddLog(*state.Log)
+	// 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
 	VmType() Type
 
+	// Current calling depth
 	Depth() int
 	SetDepth(i int)
 
-	Call(me ContextRef, addr common.Address, data []byte, gas, price, value *big.Int) ([]byte, error)
-	CallCode(me ContextRef, addr common.Address, data []byte, gas, price, value *big.Int) ([]byte, error)
-	Create(me ContextRef, data []byte, gas, price, value *big.Int) ([]byte, error, ContextRef)
+	// Call another contract
+	Call(me ContractRef, addr common.Address, data []byte, gas, price, value *big.Int) ([]byte, error)
+	// Take another's contract code and execute within our own context
+	CallCode(me ContractRef, addr common.Address, data []byte, gas, price, value *big.Int) ([]byte, error)
+	// Create a new contract
+	Create(me ContractRef, data []byte, gas, price, value *big.Int) ([]byte, common.Address, error)
+}
+
+// Database is a EVM database for full state querying
+type Database interface {
+	GetAccount(common.Address) Account
+	CreateAccount(common.Address) Account
+
+	AddBalance(common.Address, *big.Int)
+	GetBalance(common.Address) *big.Int
+
+	GetNonce(common.Address) uint64
+	SetNonce(common.Address, uint64)
+
+	GetCode(common.Address) []byte
+	SetCode(common.Address, []byte)
+
+	AddRefund(*big.Int)
+	GetRefund() *big.Int
+
+	GetState(common.Address, common.Hash) common.Hash
+	SetState(common.Address, common.Hash, common.Hash)
+
+	Delete(common.Address) bool
+	Exist(common.Address) bool
+	IsDeleted(common.Address) bool
 }
 
 // StructLog is emited to the Environment each cycle and lists information about the curent internal state
@@ -68,18 +115,10 @@ type StructLog struct {
 type Account interface {
 	SubBalance(amount *big.Int)
 	AddBalance(amount *big.Int)
+	SetBalance(*big.Int)
+	SetNonce(uint64)
 	Balance() *big.Int
 	Address() common.Address
-}
-
-// generic transfer method
-func Transfer(from, to Account, amount *big.Int) error {
-	if from.Balance().Cmp(amount) < 0 {
-		return errors.New("Insufficient balance in account")
-	}
-
-	from.SubBalance(amount)
-	to.AddBalance(amount)
-
-	return nil
+	ReturnGas(*big.Int, *big.Int)
+	SetCode([]byte)
 }
diff --git a/core/vm/gas.go b/core/vm/gas.go
index b2f068e6e..bff0ac91b 100644
--- a/core/vm/gas.go
+++ b/core/vm/gas.go
@@ -37,6 +37,7 @@ var (
 	GasContractByte = big.NewInt(200)
 )
 
+// baseCheck checks for any stack error underflows
 func baseCheck(op OpCode, stack *stack, gas *big.Int) error {
 	// PUSH and DUP are a bit special. They all cost the same but we do want to have checking on stack push limit
 	// PUSH is also allowed to calculate the same price for all PUSHes
@@ -63,6 +64,7 @@ func baseCheck(op OpCode, stack *stack, gas *big.Int) error {
 	return nil
 }
 
+// casts a arbitrary number to the amount of words (sets of 32 bytes)
 func toWordSize(size *big.Int) *big.Int {
 	tmp := new(big.Int)
 	tmp.Add(size, u256(31))
diff --git a/core/vm/instructions.go b/core/vm/instructions.go
index aa0117cc8..6c6039f74 100644
--- a/core/vm/instructions.go
+++ b/core/vm/instructions.go
@@ -20,46 +20,52 @@ import (
 	"math/big"
 
 	"github.com/ethereum/go-ethereum/common"
-	"github.com/ethereum/go-ethereum/core/state"
 	"github.com/ethereum/go-ethereum/crypto"
 	"github.com/ethereum/go-ethereum/params"
 )
 
-type instrFn func(instr instruction, env Environment, context *Context, memory *Memory, stack *stack)
-type instrExFn func(instr instruction, ret *big.Int, env Environment, context *Context, memory *Memory, stack *stack)
+type programInstruction interface {
+	Do(instr instruction, pc *uint64, env Environment, contract *Contract, memory *Memory, stack *stack)
+}
+
+type instrFn func(instr instruction, pc *uint64, env Environment, contract *Contract, memory *Memory, stack *stack)
+
+// Do executes the function. This implements programInstruction
+func (fn instrFn) Do(instr instruction, pc *uint64, env Environment, contract *Contract, memory *Memory, stack *stack) {
+	fn(instr, pc, env, contract, memory, stack)
+}
 
 type instruction struct {
-	op     OpCode
-	pc     uint64
-	fn     instrFn
-	specFn instrExFn
-	data   *big.Int
+	op   OpCode
+	pc   uint64
+	fn   instrFn
+	data *big.Int
 
 	gas   *big.Int
 	spop  int
 	spush int
 }
 
-func opStaticJump(instr instruction, ret *big.Int, env Environment, context *Context, memory *Memory, stack *stack) {
+func opStaticJump(instr instruction, pc *uint64, ret *big.Int, env Environment, contract *Contract, memory *Memory, stack *stack) {
 	ret.Set(instr.data)
 }
 
-func opAdd(instr instruction, env Environment, context *Context, memory *Memory, stack *stack) {
+func opAdd(instr instruction, pc *uint64, env Environment, contract *Contract, memory *Memory, stack *stack) {
 	x, y := stack.pop(), stack.pop()
 	stack.push(U256(x.Add(x, y)))
 }
 
-func opSub(instr instruction, env Environment, context *Context, memory *Memory, stack *stack) {
+func opSub(instr instruction, pc *uint64, env Environment, contract *Contract, memory *Memory, stack *stack) {
 	x, y := stack.pop(), stack.pop()
 	stack.push(U256(x.Sub(x, y)))
 }
 
-func opMul(instr instruction, env Environment, context *Context, memory *Memory, stack *stack) {
+func opMul(instr instruction, pc *uint64, env Environment, contract *Contract, memory *Memory, stack *stack) {
 	x, y := stack.pop(), stack.pop()
 	stack.push(U256(x.Mul(x, y)))
 }
 
-func opDiv(instr instruction, env Environment, context *Context, memory *Memory, stack *stack) {
+func opDiv(instr instruction, pc *uint64, env Environment, contract *Contract, memory *Memory, stack *stack) {
 	x, y := stack.pop(), stack.pop()
 	if y.Cmp(common.Big0) != 0 {
 		stack.push(U256(x.Div(x, y)))
@@ -68,7 +74,7 @@ func opDiv(instr instruction, env Environment, context *Context, memory *Memory,
 	}
 }
 
-func opSdiv(instr instruction, env Environment, context *Context, memory *Memory, stack *stack) {
+func opSdiv(instr instruction, pc *uint64, env Environment, contract *Contract, memory *Memory, stack *stack) {
 	x, y := S256(stack.pop()), S256(stack.pop())
 	if y.Cmp(common.Big0) == 0 {
 		stack.push(new(big.Int))
@@ -88,7 +94,7 @@ func opSdiv(instr instruction, env Environment, context *Context, memory *Memory
 	}
 }
 
-func opMod(instr instruction, env Environment, context *Context, memory *Memory, stack *stack) {
+func opMod(instr instruction, pc *uint64, env Environment, contract *Contract, memory *Memory, stack *stack) {
 	x, y := stack.pop(), stack.pop()
 	if y.Cmp(common.Big0) == 0 {
 		stack.push(new(big.Int))
@@ -97,7 +103,7 @@ func opMod(instr instruction, env Environment, context *Context, memory *Memory,
 	}
 }
 
-func opSmod(instr instruction, env Environment, context *Context, memory *Memory, stack *stack) {
+func opSmod(instr instruction, pc *uint64, env Environment, contract *Contract, memory *Memory, stack *stack) {
 	x, y := S256(stack.pop()), S256(stack.pop())
 
 	if y.Cmp(common.Big0) == 0 {
@@ -117,12 +123,12 @@ func opSmod(instr instruction, env Environment, context *Context, memory *Memory
 	}
 }
 
-func opExp(instr instruction, env Environment, context *Context, memory *Memory, stack *stack) {
+func opExp(instr instruction, pc *uint64, env Environment, contract *Contract, memory *Memory, stack *stack) {
 	x, y := stack.pop(), stack.pop()
 	stack.push(U256(x.Exp(x, y, Pow256)))
 }
 
-func opSignExtend(instr instruction, env Environment, context *Context, memory *Memory, stack *stack) {
+func opSignExtend(instr instruction, pc *uint64, env Environment, contract *Contract, memory *Memory, stack *stack) {
 	back := stack.pop()
 	if back.Cmp(big.NewInt(31)) < 0 {
 		bit := uint(back.Uint64()*8 + 7)
@@ -139,12 +145,12 @@ func opSignExtend(instr instruction, env Environment, context *Context, memory *
 	}
 }
 
-func opNot(instr instruction, env Environment, context *Context, memory *Memory, stack *stack) {
+func opNot(instr instruction, pc *uint64, env Environment, contract *Contract, memory *Memory, stack *stack) {
 	x := stack.pop()
 	stack.push(U256(x.Not(x)))
 }
 
-func opLt(instr instruction, env Environment, context *Context, memory *Memory, stack *stack) {
+func opLt(instr instruction, pc *uint64, env Environment, contract *Contract, memory *Memory, stack *stack) {
 	x, y := stack.pop(), stack.pop()
 	if x.Cmp(y) < 0 {
 		stack.push(big.NewInt(1))
@@ -153,7 +159,7 @@ func opLt(instr instruction, env Environment, context *Context, memory *Memory,
 	}
 }
 
-func opGt(instr instruction, env Environment, context *Context, memory *Memory, stack *stack) {
+func opGt(instr instruction, pc *uint64, env Environment, contract *Contract, memory *Memory, stack *stack) {
 	x, y := stack.pop(), stack.pop()
 	if x.Cmp(y) > 0 {
 		stack.push(big.NewInt(1))
@@ -162,7 +168,7 @@ func opGt(instr instruction, env Environment, context *Context, memory *Memory,
 	}
 }
 
-func opSlt(instr instruction, env Environment, context *Context, memory *Memory, stack *stack) {
+func opSlt(instr instruction, pc *uint64, env Environment, contract *Contract, memory *Memory, stack *stack) {
 	x, y := S256(stack.pop()), S256(stack.pop())
 	if x.Cmp(S256(y)) < 0 {
 		stack.push(big.NewInt(1))
@@ -171,7 +177,7 @@ func opSlt(instr instruction, env Environment, context *Context, memory *Memory,
 	}
 }
 
-func opSgt(instr instruction, env Environment, context *Context, memory *Memory, stack *stack) {
+func opSgt(instr instruction, pc *uint64, env Environment, contract *Contract, memory *Memory, stack *stack) {
 	x, y := S256(stack.pop()), S256(stack.pop())
 	if x.Cmp(y) > 0 {
 		stack.push(big.NewInt(1))
@@ -180,7 +186,7 @@ func opSgt(instr instruction, env Environment, context *Context, memory *Memory,
 	}
 }
 
-func opEq(instr instruction, env Environment, context *Context, memory *Memory, stack *stack) {
+func opEq(instr instruction, pc *uint64, env Environment, contract *Contract, memory *Memory, stack *stack) {
 	x, y := stack.pop(), stack.pop()
 	if x.Cmp(y) == 0 {
 		stack.push(big.NewInt(1))
@@ -189,7 +195,7 @@ func opEq(instr instruction, env Environment, context *Context, memory *Memory,
 	}
 }
 
-func opIszero(instr instruction, env Environment, context *Context, memory *Memory, stack *stack) {
+func opIszero(instr instruction, pc *uint64, env Environment, contract *Contract, memory *Memory, stack *stack) {
 	x := stack.pop()
 	if x.Cmp(common.Big0) > 0 {
 		stack.push(new(big.Int))
@@ -198,19 +204,19 @@ func opIszero(instr instruction, env Environment, context *Context, memory *Memo
 	}
 }
 
-func opAnd(instr instruction, env Environment, context *Context, memory *Memory, stack *stack) {
+func opAnd(instr instruction, pc *uint64, env Environment, contract *Contract, memory *Memory, stack *stack) {
 	x, y := stack.pop(), stack.pop()
 	stack.push(x.And(x, y))
 }
-func opOr(instr instruction, env Environment, context *Context, memory *Memory, stack *stack) {
+func opOr(instr instruction, pc *uint64, env Environment, contract *Contract, memory *Memory, stack *stack) {
 	x, y := stack.pop(), stack.pop()
 	stack.push(x.Or(x, y))
 }
-func opXor(instr instruction, env Environment, context *Context, memory *Memory, stack *stack) {
+func opXor(instr instruction, pc *uint64, env Environment, contract *Contract, memory *Memory, stack *stack) {
 	x, y := stack.pop(), stack.pop()
 	stack.push(x.Xor(x, y))
 }
-func opByte(instr instruction, env Environment, context *Context, memory *Memory, stack *stack) {
+func opByte(instr instruction, pc *uint64, env Environment, contract *Contract, memory *Memory, stack *stack) {
 	th, val := stack.pop(), stack.pop()
 	if th.Cmp(big.NewInt(32)) < 0 {
 		byte := big.NewInt(int64(common.LeftPadBytes(val.Bytes(), 32)[th.Int64()]))
@@ -219,7 +225,7 @@ func opByte(instr instruction, env Environment, context *Context, memory *Memory
 		stack.push(new(big.Int))
 	}
 }
-func opAddmod(instr instruction, env Environment, context *Context, memory *Memory, stack *stack) {
+func opAddmod(instr instruction, pc *uint64, env Environment, contract *Contract, memory *Memory, stack *stack) {
 	x, y, z := stack.pop(), stack.pop(), stack.pop()
 	if z.Cmp(Zero) > 0 {
 		add := x.Add(x, y)
@@ -229,7 +235,7 @@ func opAddmod(instr instruction, env Environment, context *Context, memory *Memo
 		stack.push(new(big.Int))
 	}
 }
-func opMulmod(instr instruction, env Environment, context *Context, memory *Memory, stack *stack) {
+func opMulmod(instr instruction, pc *uint64, env Environment, contract *Contract, memory *Memory, stack *stack) {
 	x, y, z := stack.pop(), stack.pop(), stack.pop()
 	if z.Cmp(Zero) > 0 {
 		mul := x.Mul(x, y)
@@ -240,92 +246,92 @@ func opMulmod(instr instruction, env Environment, context *Context, memory *Memo
 	}
 }
 
-func opSha3(instr instruction, env Environment, context *Context, memory *Memory, stack *stack) {
+func opSha3(instr instruction, pc *uint64, env Environment, contract *Contract, memory *Memory, stack *stack) {
 	offset, size := stack.pop(), stack.pop()
 	hash := crypto.Sha3(memory.Get(offset.Int64(), size.Int64()))
 
 	stack.push(common.BytesToBig(hash))
 }
 
-func opAddress(instr instruction, env Environment, context *Context, memory *Memory, stack *stack) {
-	stack.push(common.Bytes2Big(context.Address().Bytes()))
+func opAddress(instr instruction, pc *uint64, env Environment, contract *Contract, memory *Memory, stack *stack) {
+	stack.push(common.Bytes2Big(contract.Address().Bytes()))
 }
 
-func opBalance(instr instruction, env Environment, context *Context, memory *Memory, stack *stack) {
+func opBalance(instr instruction, pc *uint64, env Environment, contract *Contract, memory *Memory, stack *stack) {
 	addr := common.BigToAddress(stack.pop())
-	balance := env.State().GetBalance(addr)
+	balance := env.Db().GetBalance(addr)
 
 	stack.push(new(big.Int).Set(balance))
 }
 
-func opOrigin(instr instruction, env Environment, context *Context, memory *Memory, stack *stack) {
+func opOrigin(instr instruction, pc *uint64, env Environment, contract *Contract, memory *Memory, stack *stack) {
 	stack.push(env.Origin().Big())
 }
 
-func opCaller(instr instruction, env Environment, context *Context, memory *Memory, stack *stack) {
-	stack.push(common.Bytes2Big(context.caller.Address().Bytes()))
+func opCaller(instr instruction, pc *uint64, env Environment, contract *Contract, memory *Memory, stack *stack) {
+	stack.push(common.Bytes2Big(contract.caller.Address().Bytes()))
 }
 
-func opCallValue(instr instruction, env Environment, context *Context, memory *Memory, stack *stack) {
-	stack.push(new(big.Int).Set(context.value))
+func opCallValue(instr instruction, pc *uint64, env Environment, contract *Contract, memory *Memory, stack *stack) {
+	stack.push(new(big.Int).Set(contract.value))
 }
 
-func opCalldataLoad(instr instruction, env Environment, context *Context, memory *Memory, stack *stack) {
-	stack.push(common.Bytes2Big(getData(context.Input, stack.pop(), common.Big32)))
+func opCalldataLoad(instr instruction, pc *uint64, env Environment, contract *Contract, memory *Memory, stack *stack) {
+	stack.push(common.Bytes2Big(getData(contract.Input, stack.pop(), common.Big32)))
 }
 
-func opCalldataSize(instr instruction, env Environment, context *Context, memory *Memory, stack *stack) {
-	stack.push(big.NewInt(int64(len(context.Input))))
+func opCalldataSize(instr instruction, pc *uint64, env Environment, contract *Contract, memory *Memory, stack *stack) {
+	stack.push(big.NewInt(int64(len(contract.Input))))
 }
 
-func opCalldataCopy(instr instruction, env Environment, context *Context, memory *Memory, stack *stack) {
+func opCalldataCopy(instr instruction, pc *uint64, env Environment, contract *Contract, memory *Memory, stack *stack) {
 	var (
 		mOff = stack.pop()
 		cOff = stack.pop()
 		l    = stack.pop()
 	)
-	memory.Set(mOff.Uint64(), l.Uint64(), getData(context.Input, cOff, l))
+	memory.Set(mOff.Uint64(), l.Uint64(), getData(contract.Input, cOff, l))
 }
 
-func opExtCodeSize(instr instruction, env Environment, context *Context, memory *Memory, stack *stack) {
+func opExtCodeSize(instr instruction, pc *uint64, env Environment, contract *Contract, memory *Memory, stack *stack) {
 	addr := common.BigToAddress(stack.pop())
-	l := big.NewInt(int64(len(env.State().GetCode(addr))))
+	l := big.NewInt(int64(len(env.Db().GetCode(addr))))
 	stack.push(l)
 }
 
-func opCodeSize(instr instruction, env Environment, context *Context, memory *Memory, stack *stack) {
-	l := big.NewInt(int64(len(context.Code)))
+func opCodeSize(instr instruction, pc *uint64, env Environment, contract *Contract, memory *Memory, stack *stack) {
+	l := big.NewInt(int64(len(contract.Code)))
 	stack.push(l)
 }
 
-func opCodeCopy(instr instruction, env Environment, context *Context, memory *Memory, stack *stack) {
+func opCodeCopy(instr instruction, pc *uint64, env Environment, contract *Contract, memory *Memory, stack *stack) {
 	var (
 		mOff = stack.pop()
 		cOff = stack.pop()
 		l    = stack.pop()
 	)
-	codeCopy := getData(context.Code, cOff, l)
+	codeCopy := getData(contract.Code, cOff, l)
 
 	memory.Set(mOff.Uint64(), l.Uint64(), codeCopy)
 }
 
-func opExtCodeCopy(instr instruction, env Environment, context *Context, memory *Memory, stack *stack) {
+func opExtCodeCopy(instr instruction, pc *uint64, env Environment, contract *Contract, memory *Memory, stack *stack) {
 	var (
 		addr = common.BigToAddress(stack.pop())
 		mOff = stack.pop()
 		cOff = stack.pop()
 		l    = stack.pop()
 	)
-	codeCopy := getData(env.State().GetCode(addr), cOff, l)
+	codeCopy := getData(env.Db().GetCode(addr), cOff, l)
 
 	memory.Set(mOff.Uint64(), l.Uint64(), codeCopy)
 }
 
-func opGasprice(instr instruction, env Environment, context *Context, memory *Memory, stack *stack) {
-	stack.push(new(big.Int).Set(context.Price))
+func opGasprice(instr instruction, pc *uint64, env Environment, contract *Contract, memory *Memory, stack *stack) {
+	stack.push(new(big.Int).Set(contract.Price))
 }
 
-func opBlockhash(instr instruction, env Environment, context *Context, memory *Memory, stack *stack) {
+func opBlockhash(instr instruction, pc *uint64, env Environment, contract *Contract, memory *Memory, stack *stack) {
 	num := stack.pop()
 
 	n := new(big.Int).Sub(env.BlockNumber(), common.Big257)
@@ -336,43 +342,43 @@ func opBlockhash(instr instruction, env Environment, context *Context, memory *M
 	}
 }
 
-func opCoinbase(instr instruction, env Environment, context *Context, memory *Memory, stack *stack) {
+func opCoinbase(instr instruction, pc *uint64, env Environment, contract *Contract, memory *Memory, stack *stack) {
 	stack.push(env.Coinbase().Big())
 }
 
-func opTimestamp(instr instruction, env Environment, context *Context, memory *Memory, stack *stack) {
+func opTimestamp(instr instruction, pc *uint64, env Environment, contract *Contract, memory *Memory, stack *stack) {
 	stack.push(U256(new(big.Int).Set(env.Time())))
 }
 
-func opNumber(instr instruction, env Environment, context *Context, memory *Memory, stack *stack) {
+func opNumber(instr instruction, pc *uint64, env Environment, contract *Contract, memory *Memory, stack *stack) {
 	stack.push(U256(new(big.Int).Set(env.BlockNumber())))
 }
 
-func opDifficulty(instr instruction, env Environment, context *Context, memory *Memory, stack *stack) {
+func opDifficulty(instr instruction, pc *uint64, env Environment, contract *Contract, memory *Memory, stack *stack) {
 	stack.push(U256(new(big.Int).Set(env.Difficulty())))
 }
 
-func opGasLimit(instr instruction, env Environment, context *Context, memory *Memory, stack *stack) {
+func opGasLimit(instr instruction, pc *uint64, env Environment, contract *Contract, memory *Memory, stack *stack) {
 	stack.push(U256(new(big.Int).Set(env.GasLimit())))
 }
 
-func opPop(instr instruction, env Environment, context *Context, memory *Memory, stack *stack) {
+func opPop(instr instruction, pc *uint64, env Environment, contract *Contract, memory *Memory, stack *stack) {
 	stack.pop()
 }
 
-func opPush(instr instruction, env Environment, context *Context, memory *Memory, stack *stack) {
+func opPush(instr instruction, pc *uint64, env Environment, contract *Contract, memory *Memory, stack *stack) {
 	stack.push(new(big.Int).Set(instr.data))
 }
 
-func opDup(instr instruction, env Environment, context *Context, memory *Memory, stack *stack) {
+func opDup(instr instruction, pc *uint64, env Environment, contract *Contract, memory *Memory, stack *stack) {
 	stack.dup(int(instr.data.Int64()))
 }
 
-func opSwap(instr instruction, env Environment, context *Context, memory *Memory, stack *stack) {
+func opSwap(instr instruction, pc *uint64, env Environment, contract *Contract, memory *Memory, stack *stack) {
 	stack.swap(int(instr.data.Int64()))
 }
 
-func opLog(instr instruction, env Environment, context *Context, memory *Memory, stack *stack) {
+func opLog(instr instruction, pc *uint64, env Environment, contract *Contract, memory *Memory, stack *stack) {
 	n := int(instr.data.Int64())
 	topics := make([]common.Hash, n)
 	mStart, mSize := stack.pop(), stack.pop()
@@ -381,85 +387,88 @@ func opLog(instr instruction, env Environment, context *Context, memory *Memory,
 	}
 
 	d := memory.Get(mStart.Int64(), mSize.Int64())
-	log := state.NewLog(context.Address(), topics, d, env.BlockNumber().Uint64())
+	log := NewLog(contract.Address(), topics, d, env.BlockNumber().Uint64())
 	env.AddLog(log)
 }
 
-func opMload(instr instruction, env Environment, context *Context, memory *Memory, stack *stack) {
+func opMload(instr instruction, pc *uint64, env Environment, contract *Contract, memory *Memory, stack *stack) {
 	offset := stack.pop()
 	val := common.BigD(memory.Get(offset.Int64(), 32))
 	stack.push(val)
 }
 
-func opMstore(instr instruction, env Environment, context *Context, memory *Memory, stack *stack) {
+func opMstore(instr instruction, pc *uint64, env Environment, contract *Contract, memory *Memory, stack *stack) {
 	// pop value of the stack
 	mStart, val := stack.pop(), stack.pop()
 	memory.Set(mStart.Uint64(), 32, common.BigToBytes(val, 256))
 }
 
-func opMstore8(instr instruction, env Environment, context *Context, memory *Memory, stack *stack) {
+func opMstore8(instr instruction, pc *uint64, env Environment, contract *Contract, memory *Memory, stack *stack) {
 	off, val := stack.pop().Int64(), stack.pop().Int64()
 	memory.store[off] = byte(val & 0xff)
 }
 
-func opSload(instr instruction, env Environment, context *Context, memory *Memory, stack *stack) {
+func opSload(instr instruction, pc *uint64, env Environment, contract *Contract, memory *Memory, stack *stack) {
 	loc := common.BigToHash(stack.pop())
-	val := env.State().GetState(context.Address(), loc).Big()
+	val := env.Db().GetState(contract.Address(), loc).Big()
 	stack.push(val)
 }
 
-func opSstore(instr instruction, env Environment, context *Context, memory *Memory, stack *stack) {
+func opSstore(instr instruction, pc *uint64, env Environment, contract *Contract, memory *Memory, stack *stack) {
 	loc := common.BigToHash(stack.pop())
 	val := stack.pop()
 
-	env.State().SetState(context.Address(), loc, common.BigToHash(val))
+	env.Db().SetState(contract.Address(), loc, common.BigToHash(val))
 }
 
-func opJump(instr instruction, env Environment, context *Context, memory *Memory, stack *stack)     {}
-func opJumpi(instr instruction, env Environment, context *Context, memory *Memory, stack *stack)    {}
-func opJumpdest(instr instruction, env Environment, context *Context, memory *Memory, stack *stack) {}
+func opJump(instr instruction, pc *uint64, env Environment, contract *Contract, memory *Memory, stack *stack) {
+}
+func opJumpi(instr instruction, pc *uint64, env Environment, contract *Contract, memory *Memory, stack *stack) {
+}
+func opJumpdest(instr instruction, pc *uint64, env Environment, contract *Contract, memory *Memory, stack *stack) {
+}
 
-func opPc(instr instruction, env Environment, context *Context, memory *Memory, stack *stack) {
+func opPc(instr instruction, pc *uint64, env Environment, contract *Contract, memory *Memory, stack *stack) {
 	stack.push(new(big.Int).Set(instr.data))
 }
 
-func opMsize(instr instruction, env Environment, context *Context, memory *Memory, stack *stack) {
+func opMsize(instr instruction, pc *uint64, env Environment, contract *Contract, memory *Memory, stack *stack) {
 	stack.push(big.NewInt(int64(memory.Len())))
 }
 
-func opGas(instr instruction, env Environment, context *Context, memory *Memory, stack *stack) {
-	stack.push(new(big.Int).Set(context.Gas))
+func opGas(instr instruction, pc *uint64, env Environment, contract *Contract, memory *Memory, stack *stack) {
+	stack.push(new(big.Int).Set(contract.Gas))
 }
 
-func opCreate(instr instruction, env Environment, context *Context, memory *Memory, stack *stack) {
+func opCreate(instr instruction, pc *uint64, env Environment, contract *Contract, memory *Memory, stack *stack) {
 	var (
 		value        = stack.pop()
 		offset, size = stack.pop(), stack.pop()
 		input        = memory.Get(offset.Int64(), size.Int64())
-		gas          = new(big.Int).Set(context.Gas)
+		gas          = new(big.Int).Set(contract.Gas)
 		addr         common.Address
+		ret          []byte
+		suberr       error
 	)
 
-	context.UseGas(context.Gas)
-	ret, suberr, ref := env.Create(context, input, gas, context.Price, value)
+	contract.UseGas(contract.Gas)
+	ret, addr, suberr = env.Create(contract, input, gas, contract.Price, value)
 	if suberr != nil {
 		stack.push(new(big.Int))
-
 	} else {
 		// gas < len(ret) * Createinstr.dataGas == NO_CODE
 		dataGas := big.NewInt(int64(len(ret)))
 		dataGas.Mul(dataGas, params.CreateDataGas)
-		if context.UseGas(dataGas) {
-			ref.SetCode(ret)
+		if contract.UseGas(dataGas) {
+			env.Db().SetCode(addr, ret)
 		}
-		addr = ref.Address()
 
 		stack.push(addr.Big())
 
 	}
 }
 
-func opCall(instr instruction, env Environment, context *Context, memory *Memory, stack *stack) {
+func opCall(instr instruction, pc *uint64, env Environment, contract *Contract, memory *Memory, stack *stack) {
 	gas := stack.pop()
 	// pop gas and value of the stack.
 	addr, value := stack.pop(), stack.pop()
@@ -478,7 +487,7 @@ func opCall(instr instruction, env Environment, context *Context, memory *Memory
 		gas.Add(gas, params.CallStipend)
 	}
 
-	ret, err := env.Call(context, address, args, gas, context.Price, value)
+	ret, err := env.Call(contract, address, args, gas, contract.Price, value)
 
 	if err != nil {
 		stack.push(new(big.Int))
@@ -490,7 +499,7 @@ func opCall(instr instruction, env Environment, context *Context, memory *Memory
 	}
 }
 
-func opCallCode(instr instruction, env Environment, context *Context, memory *Memory, stack *stack) {
+func opCallCode(instr instruction, pc *uint64, env Environment, contract *Contract, memory *Memory, stack *stack) {
 	gas := stack.pop()
 	// pop gas and value of the stack.
 	addr, value := stack.pop(), stack.pop()
@@ -509,7 +518,7 @@ func opCallCode(instr instruction, env Environment, context *Context, memory *Me
 		gas.Add(gas, params.CallStipend)
 	}
 
-	ret, err := env.CallCode(context, address, args, gas, context.Price, value)
+	ret, err := env.CallCode(contract, address, args, gas, contract.Price, value)
 
 	if err != nil {
 		stack.push(new(big.Int))
@@ -521,14 +530,58 @@ func opCallCode(instr instruction, env Environment, context *Context, memory *Me
 	}
 }
 
-func opReturn(instr instruction, env Environment, context *Context, memory *Memory, stack *stack) {}
-func opStop(instr instruction, env Environment, context *Context, memory *Memory, stack *stack)   {}
+func opReturn(instr instruction, pc *uint64, env Environment, contract *Contract, memory *Memory, stack *stack) {
+}
+func opStop(instr instruction, pc *uint64, env Environment, contract *Contract, memory *Memory, stack *stack) {
+}
+
+func opSuicide(instr instruction, pc *uint64, env Environment, contract *Contract, memory *Memory, stack *stack) {
+	//receiver := env.Db().GetOrNewStateObject(common.BigToAddress(stack.pop()))
+	//receiver.AddBalance(balance)
+	balance := env.Db().GetBalance(contract.Address())
+	env.Db().AddBalance(common.BigToAddress(stack.pop()), balance)
+
+	env.Db().Delete(contract.Address())
+}
+
+// following functions are used by the instruction jump  table
+
+// make log instruction function
+func makeLog(size int) instrFn {
+	return func(instr instruction, pc *uint64, env Environment, contract *Contract, memory *Memory, stack *stack) {
+		topics := make([]common.Hash, size)
+		mStart, mSize := stack.pop(), stack.pop()
+		for i := 0; i < size; i++ {
+			topics[i] = common.BigToHash(stack.pop())
+		}
+
+		d := memory.Get(mStart.Int64(), mSize.Int64())
+		log := NewLog(contract.Address(), topics, d, env.BlockNumber().Uint64())
+		env.AddLog(log)
+	}
+}
 
-func opSuicide(instr instruction, env Environment, context *Context, memory *Memory, stack *stack) {
-	receiver := env.State().GetOrNewStateObject(common.BigToAddress(stack.pop()))
-	balance := env.State().GetBalance(context.Address())
+// make push instruction function
+func makePush(size uint64, bsize *big.Int) instrFn {
+	return func(instr instruction, pc *uint64, env Environment, contract *Contract, memory *Memory, stack *stack) {
+		byts := getData(contract.Code, new(big.Int).SetUint64(*pc+1), bsize)
+		stack.push(common.Bytes2Big(byts))
+		*pc += size
+	}
+}
 
-	receiver.AddBalance(balance)
+// make push instruction function
+func makeDup(size int64) instrFn {
+	return func(instr instruction, pc *uint64, env Environment, contract *Contract, memory *Memory, stack *stack) {
+		stack.dup(int(size))
+	}
+}
 
-	env.State().Delete(context.Address())
+// make swap instruction function
+func makeSwap(size int64) instrFn {
+	// switch n + 1 otherwise n would be swapped with n
+	size += 1
+	return func(instr instruction, pc *uint64, env Environment, contract *Contract, memory *Memory, stack *stack) {
+		stack.swap(int(size))
+	}
 }
diff --git a/core/vm/jit.go b/core/vm/jit.go
index 084d2a3f3..6ad574917 100644
--- a/core/vm/jit.go
+++ b/core/vm/jit.go
@@ -20,10 +20,12 @@ import (
 	"fmt"
 	"math/big"
 	"sync/atomic"
+	"time"
 
 	"github.com/ethereum/go-ethereum/common"
-	"github.com/ethereum/go-ethereum/core/state"
 	"github.com/ethereum/go-ethereum/crypto"
+	"github.com/ethereum/go-ethereum/logger"
+	"github.com/ethereum/go-ethereum/logger/glog"
 	"github.com/ethereum/go-ethereum/params"
 	"github.com/hashicorp/golang-lru"
 )
@@ -35,6 +37,14 @@ const (
 	progCompile
 	progReady
 	progError
+
+	defaultJitMaxCache int = 64
+)
+
+var (
+	EnableJit   bool // Enables the JIT VM
+	ForceJit    bool // Force the JIT, skip byte VM
+	MaxProgSize int  // Max cache size for JIT Programs
 )
 
 var programs *lru.Cache
@@ -74,7 +84,7 @@ type Program struct {
 	Id     common.Hash // Id of the program
 	status int32       // status should be accessed atomically
 
-	context *Context
+	contract *Contract
 
 	instructions []instruction       // instruction set
 	mapping      map[uint64]int      // real PC mapping to array indices
@@ -108,7 +118,7 @@ func (p *Program) addInstr(op OpCode, pc uint64, fn instrFn, data *big.Int) {
 		baseOp = DUP1
 	}
 	base := _baseCheck[baseOp]
-	instr := instruction{op, pc, fn, nil, data, base.gas, base.stackPop, base.stackPush}
+	instr := instruction{op, pc, fn, data, base.gas, base.stackPop, base.stackPush}
 
 	p.instructions = append(p.instructions, instr)
 	p.mapping[pc] = len(p.instructions) - 1
@@ -127,6 +137,13 @@ func CompileProgram(program *Program) (err error) {
 			atomic.StoreInt32(&program.status, int32(progReady))
 		}
 	}()
+	if glog.V(logger.Debug) {
+		glog.Infof("compiling %x\n", program.Id[:4])
+		tstart := time.Now()
+		defer func() {
+			glog.Infof("compiled  %x instrc: %d time: %v\n", program.Id[:4], len(program.instructions), time.Since(tstart))
+		}()
+	}
 
 	// loop thru the opcodes and "compile" in to instructions
 	for pc := uint64(0); pc < uint64(len(program.code)); pc++ {
@@ -264,7 +281,7 @@ func CompileProgram(program *Program) (err error) {
 			program.addInstr(op, pc, opReturn, nil)
 		case SUICIDE:
 			program.addInstr(op, pc, opSuicide, nil)
-		case STOP: // Stop the context
+		case STOP: // Stop the contract
 			program.addInstr(op, pc, opStop, nil)
 		default:
 			program.addInstr(op, pc, nil, nil)
@@ -274,23 +291,24 @@ func CompileProgram(program *Program) (err error) {
 	return nil
 }
 
-// RunProgram runs the program given the enviroment and context and returns an
+// RunProgram runs the program given the enviroment and contract and returns an
 // error if the execution failed (non-consensus)
-func RunProgram(program *Program, env Environment, context *Context, input []byte) ([]byte, error) {
-	return runProgram(program, 0, NewMemory(), newstack(), env, context, input)
+func RunProgram(program *Program, env Environment, contract *Contract, input []byte) ([]byte, error) {
+	return runProgram(program, 0, NewMemory(), newstack(), env, contract, input)
 }
 
-func runProgram(program *Program, pcstart uint64, mem *Memory, stack *stack, env Environment, context *Context, input []byte) ([]byte, error) {
-	context.Input = input
+func runProgram(program *Program, pcstart uint64, mem *Memory, stack *stack, env Environment, contract *Contract, input []byte) ([]byte, error) {
+	contract.Input = input
 
 	var (
-		caller      = context.caller
-		statedb     = env.State()
-		pc      int = program.mapping[pcstart]
+		caller         = contract.caller
+		statedb        = env.Db()
+		pc         int = program.mapping[pcstart]
+		instrCount     = 0
 
 		jump = func(to *big.Int) error {
 			if !validDest(program.destinations, to) {
-				nop := context.GetOp(to.Uint64())
+				nop := contract.GetOp(to.Uint64())
 				return fmt.Errorf("invalid jump destination (%v) %v", nop, to)
 			}
 
@@ -300,18 +318,28 @@ func runProgram(program *Program, pcstart uint64, mem *Memory, stack *stack, env
 		}
 	)
 
+	if glog.V(logger.Debug) {
+		glog.Infof("running JIT program %x\n", program.Id[:4])
+		tstart := time.Now()
+		defer func() {
+			glog.Infof("JIT program %x done. time: %v instrc: %v\n", program.Id[:4], time.Since(tstart), instrCount)
+		}()
+	}
+
 	for pc < len(program.instructions) {
+		instrCount++
+
 		instr := program.instructions[pc]
 
 		// calculate the new memory size and gas price for the current executing opcode
-		newMemSize, cost, err := jitCalculateGasAndSize(env, context, caller, instr, statedb, mem, stack)
+		newMemSize, cost, err := jitCalculateGasAndSize(env, contract, caller, instr, statedb, mem, stack)
 		if err != nil {
 			return nil, err
 		}
 
 		// Use the calculated gas. When insufficient gas is present, use all gas and return an
 		// Out Of Gas error
-		if !context.UseGas(cost) {
+		if !contract.UseGas(cost) {
 			return nil, OutOfGasError
 		}
 		// Resize the memory calculated previously
@@ -338,27 +366,27 @@ func runProgram(program *Program, pcstart uint64, mem *Memory, stack *stack, env
 			offset, size := stack.pop(), stack.pop()
 			ret := mem.GetPtr(offset.Int64(), size.Int64())
 
-			return context.Return(ret), nil
+			return contract.Return(ret), nil
 		case SUICIDE:
-			instr.fn(instr, env, context, mem, stack)
+			instr.fn(instr, nil, env, contract, mem, stack)
 
-			return context.Return(nil), nil
+			return contract.Return(nil), nil
 		case STOP:
-			return context.Return(nil), nil
+			return contract.Return(nil), nil
 		default:
 			if instr.fn == nil {
 				return nil, fmt.Errorf("Invalid opcode %x", instr.op)
 			}
 
-			instr.fn(instr, env, context, mem, stack)
+			instr.fn(instr, nil, env, contract, mem, stack)
 		}
 
 		pc++
 	}
 
-	context.Input = nil
+	contract.Input = nil
 
-	return context.Return(nil), nil
+	return contract.Return(nil), nil
 }
 
 // validDest checks if the given distination is a valid one given the
@@ -375,7 +403,7 @@ func validDest(dests map[uint64]struct{}, dest *big.Int) bool {
 
 // jitCalculateGasAndSize calculates the required given the opcode and stack items calculates the new memorysize for
 // the operation. This does not reduce gas or resizes the memory.
-func jitCalculateGasAndSize(env Environment, context *Context, caller ContextRef, instr instruction, statedb *state.StateDB, mem *Memory, stack *stack) (*big.Int, *big.Int, error) {
+func jitCalculateGasAndSize(env Environment, contract *Contract, caller ContractRef, instr instruction, statedb Database, mem *Memory, stack *stack) (*big.Int, *big.Int, error) {
 	var (
 		gas                 = new(big.Int)
 		newMemSize *big.Int = new(big.Int)
@@ -426,27 +454,25 @@ func jitCalculateGasAndSize(env Environment, context *Context, caller ContextRef
 
 		var g *big.Int
 		y, x := stack.data[stack.len()-2], stack.data[stack.len()-1]
-		val := statedb.GetState(context.Address(), common.BigToHash(x))
+		val := statedb.GetState(contract.Address(), common.BigToHash(x))
 
 		// 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 nen-zero to a non-zero                         (CHANGE)
 		if common.EmptyHash(val) && !common.EmptyHash(common.BigToHash(y)) {
-			// 0 => non 0
 			g = params.SstoreSetGas
 		} else if !common.EmptyHash(val) && common.EmptyHash(common.BigToHash(y)) {
-			statedb.Refund(params.SstoreRefundGas)
+			statedb.AddRefund(params.SstoreRefundGas)
 
 			g = params.SstoreClearGas
 		} else {
-			// non 0 => non 0 (or 0 => 0)
 			g = params.SstoreClearGas
 		}
 		gas.Set(g)
 	case SUICIDE:
-		if !statedb.IsDeleted(context.Address()) {
-			statedb.Refund(params.SuicideRefundGas)
+		if !statedb.IsDeleted(contract.Address()) {
+			statedb.AddRefund(params.SuicideRefundGas)
 		}
 	case MLOAD:
 		newMemSize = calcMemSize(stack.peek(), u256(32))
@@ -483,7 +509,8 @@ func jitCalculateGasAndSize(env Environment, context *Context, caller ContextRef
 		gas.Add(gas, stack.data[stack.len()-1])
 
 		if op == CALL {
-			if env.State().GetStateObject(common.BigToAddress(stack.data[stack.len()-2])) == nil {
+			//if env.Db().GetStateObject(common.BigToAddress(stack.data[stack.len()-2])) == nil {
+			if !env.Db().Exist(common.BigToAddress(stack.data[stack.len()-2])) {
 				gas.Add(gas, params.CallNewAccountGas)
 			}
 		}
@@ -497,29 +524,7 @@ func jitCalculateGasAndSize(env Environment, context *Context, caller ContextRef
 
 		newMemSize = common.BigMax(x, y)
 	}
-
-	if newMemSize.Cmp(common.Big0) > 0 {
-		newMemSizeWords := toWordSize(newMemSize)
-		newMemSize.Mul(newMemSizeWords, u256(32))
-
-		if newMemSize.Cmp(u256(int64(mem.Len()))) > 0 {
-			// be careful reusing variables here when changing.
-			// The order has been optimised to reduce allocation
-			oldSize := toWordSize(big.NewInt(int64(mem.Len())))
-			pow := new(big.Int).Exp(oldSize, common.Big2, Zero)
-			linCoef := oldSize.Mul(oldSize, params.MemoryGas)
-			quadCoef := new(big.Int).Div(pow, params.QuadCoeffDiv)
-			oldTotalFee := new(big.Int).Add(linCoef, quadCoef)
-
-			pow.Exp(newMemSizeWords, common.Big2, Zero)
-			linCoef = linCoef.Mul(newMemSizeWords, params.MemoryGas)
-			quadCoef = quadCoef.Div(pow, params.QuadCoeffDiv)
-			newTotalFee := linCoef.Add(linCoef, quadCoef)
-
-			fee := newTotalFee.Sub(newTotalFee, oldTotalFee)
-			gas.Add(gas, fee)
-		}
-	}
+	quadMemGas(mem, newMemSize, gas)
 
 	return newMemSize, gas, nil
 }
diff --git a/core/vm/jit_test.go b/core/vm/jit_test.go
index d8e442637..8c45f2ce7 100644
--- a/core/vm/jit_test.go
+++ b/core/vm/jit_test.go
@@ -21,13 +21,56 @@ import (
 	"time"
 
 	"github.com/ethereum/go-ethereum/common"
-	"github.com/ethereum/go-ethereum/core/state"
 	"github.com/ethereum/go-ethereum/crypto"
-	"github.com/ethereum/go-ethereum/ethdb"
 )
 
 const maxRun = 1000
 
+func TestCompiling(t *testing.T) {
+	prog := NewProgram([]byte{0x60, 0x10})
+	err := CompileProgram(prog)
+	if err != nil {
+		t.Error("didn't expect compile error")
+	}
+
+	if len(prog.instructions) != 1 {
+		t.Error("exected 1 compiled instruction, got", len(prog.instructions))
+	}
+}
+
+func TestResetInput(t *testing.T) {
+	var sender account
+
+	env := NewEnv()
+	contract := NewContract(sender, sender, big.NewInt(100), big.NewInt(10000), big.NewInt(0))
+	contract.CodeAddr = &common.Address{}
+
+	program := NewProgram([]byte{})
+	RunProgram(program, env, contract, []byte{0xbe, 0xef})
+	if contract.Input != nil {
+		t.Errorf("expected input to be nil, got %x", contract.Input)
+	}
+}
+
+func TestPcMappingToInstruction(t *testing.T) {
+	program := NewProgram([]byte{byte(PUSH2), 0xbe, 0xef, byte(ADD)})
+	CompileProgram(program)
+	if program.mapping[3] != 1 {
+		t.Error("expected mapping PC 4 to me instr no. 2, got", program.mapping[4])
+	}
+}
+
+var benchmarks = map[string]vmBench{
+	"pushes": vmBench{
+		false, false, false,
+		common.Hex2Bytes("600a600a01600a600a01600a600a01600a600a01600a600a01600a600a01600a600a01600a600a01600a600a01600a600a01"), nil,
+	},
+}
+
+func BenchmarkPushes(b *testing.B) {
+	runVmBench(benchmarks["pushes"], b)
+}
+
 type vmBench struct {
 	precompile bool // compile prior to executing
 	nojit      bool // ignore jit (sets DisbaleJit = true
@@ -37,9 +80,19 @@ type vmBench struct {
 	input []byte
 }
 
+type account struct{}
+
+func (account) SubBalance(amount *big.Int)   {}
+func (account) AddBalance(amount *big.Int)   {}
+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 runVmBench(test vmBench, b *testing.B) {
-	db, _ := ethdb.NewMemDatabase()
-	sender := state.NewStateObject(common.Address{}, db)
+	var sender account
 
 	if test.precompile && !test.forcejit {
 		NewProgram(test.code)
@@ -52,7 +105,7 @@ func runVmBench(test vmBench, b *testing.B) {
 	b.ResetTimer()
 
 	for i := 0; i < b.N; i++ {
-		context := NewContext(sender, sender, big.NewInt(100), big.NewInt(10000), big.NewInt(0))
+		context := NewContract(sender, sender, big.NewInt(100), big.NewInt(10000), big.NewInt(0))
 		context.Code = test.code
 		context.CodeAddr = &common.Address{}
 		_, err := New(env).Run(context, test.input)
@@ -63,17 +116,6 @@ func runVmBench(test vmBench, b *testing.B) {
 	}
 }
 
-var benchmarks = map[string]vmBench{
-	"pushes": vmBench{
-		false, false, false,
-		common.Hex2Bytes("600a600a01600a600a01600a600a01600a600a01600a600a01600a600a01600a600a01600a600a01600a600a01600a600a01"), nil,
-	},
-}
-
-func BenchmarkPushes(b *testing.B) {
-	runVmBench(benchmarks["pushes"], b)
-}
-
 type Env struct {
 	gasLimit *big.Int
 	depth    int
@@ -93,30 +135,32 @@ func (self *Env) StructLogs() []StructLog {
 
 //func (self *Env) PrevHash() []byte      { return self.parent }
 func (self *Env) Coinbase() common.Address { return common.Address{} }
+func (self *Env) MakeSnapshot() Database   { return nil }
+func (self *Env) SetSnapshot(Database)     {}
 func (self *Env) Time() *big.Int           { return big.NewInt(time.Now().Unix()) }
 func (self *Env) Difficulty() *big.Int     { return big.NewInt(0) }
-func (self *Env) State() *state.StateDB    { return nil }
+func (self *Env) Db() Database             { return nil }
 func (self *Env) GasLimit() *big.Int       { return self.gasLimit }
 func (self *Env) VmType() Type             { return StdVmTy }
 func (self *Env) GetHash(n uint64) common.Hash {
 	return common.BytesToHash(crypto.Sha3([]byte(big.NewInt(int64(n)).String())))
 }
-func (self *Env) AddLog(log *state.Log) {
+func (self *Env) AddLog(log *Log) {
 }
 func (self *Env) Depth() int     { return self.depth }
 func (self *Env) SetDepth(i int) { self.depth = i }
-func (self *Env) CanTransfer(from Account, balance *big.Int) bool {
-	return from.Balance().Cmp(balance) >= 0
+func (self *Env) CanTransfer(from common.Address, balance *big.Int) bool {
+	return true
 }
 func (self *Env) Transfer(from, to Account, amount *big.Int) error {
 	return nil
 }
-func (self *Env) Call(caller ContextRef, addr common.Address, data []byte, gas, price, value *big.Int) ([]byte, error) {
+func (self *Env) Call(caller ContractRef, addr common.Address, data []byte, gas, price, value *big.Int) ([]byte, error) {
 	return nil, nil
 }
-func (self *Env) CallCode(caller ContextRef, addr common.Address, data []byte, gas, price, value *big.Int) ([]byte, error) {
+func (self *Env) CallCode(caller ContractRef, addr common.Address, data []byte, gas, price, value *big.Int) ([]byte, error) {
 	return nil, nil
 }
-func (self *Env) Create(caller ContextRef, data []byte, gas, price, value *big.Int) ([]byte, error, ContextRef) {
-	return nil, nil, nil
+func (self *Env) Create(caller ContractRef, data []byte, gas, price, value *big.Int) ([]byte, common.Address, error) {
+	return nil, common.Address{}, nil
 }
diff --git a/core/vm/jump_table.go b/core/vm/jump_table.go
new file mode 100644
index 000000000..ab899647f
--- /dev/null
+++ b/core/vm/jump_table.go
@@ -0,0 +1,143 @@
+package vm
+
+import "math/big"
+
+type jumpPtr struct {
+	fn    instrFn
+	valid bool
+}
+
+var jumpTable [256]jumpPtr
+
+func init() {
+	jumpTable[ADD] = jumpPtr{opAdd, true}
+	jumpTable[SUB] = jumpPtr{opSub, true}
+	jumpTable[MUL] = jumpPtr{opMul, true}
+	jumpTable[DIV] = jumpPtr{opDiv, true}
+	jumpTable[SDIV] = jumpPtr{opSdiv, true}
+	jumpTable[MOD] = jumpPtr{opMod, true}
+	jumpTable[SMOD] = jumpPtr{opSmod, true}
+	jumpTable[EXP] = jumpPtr{opExp, true}
+	jumpTable[SIGNEXTEND] = jumpPtr{opSignExtend, true}
+	jumpTable[NOT] = jumpPtr{opNot, true}
+	jumpTable[LT] = jumpPtr{opLt, true}
+	jumpTable[GT] = jumpPtr{opGt, true}
+	jumpTable[SLT] = jumpPtr{opSlt, true}
+	jumpTable[SGT] = jumpPtr{opSgt, true}
+	jumpTable[EQ] = jumpPtr{opEq, true}
+	jumpTable[ISZERO] = jumpPtr{opIszero, true}
+	jumpTable[AND] = jumpPtr{opAnd, true}
+	jumpTable[OR] = jumpPtr{opOr, true}
+	jumpTable[XOR] = jumpPtr{opXor, true}
+	jumpTable[BYTE] = jumpPtr{opByte, true}
+	jumpTable[ADDMOD] = jumpPtr{opAddmod, true}
+	jumpTable[MULMOD] = jumpPtr{opMulmod, true}
+	jumpTable[SHA3] = jumpPtr{opSha3, true}
+	jumpTable[ADDRESS] = jumpPtr{opAddress, true}
+	jumpTable[BALANCE] = jumpPtr{opBalance, true}
+	jumpTable[ORIGIN] = jumpPtr{opOrigin, true}
+	jumpTable[CALLER] = jumpPtr{opCaller, true}
+	jumpTable[CALLVALUE] = jumpPtr{opCallValue, true}
+	jumpTable[CALLDATALOAD] = jumpPtr{opCalldataLoad, true}
+	jumpTable[CALLDATASIZE] = jumpPtr{opCalldataSize, true}
+	jumpTable[CALLDATACOPY] = jumpPtr{opCalldataCopy, true}
+	jumpTable[CODESIZE] = jumpPtr{opCodeSize, true}
+	jumpTable[EXTCODESIZE] = jumpPtr{opExtCodeSize, true}
+	jumpTable[CODECOPY] = jumpPtr{opCodeCopy, true}
+	jumpTable[EXTCODECOPY] = jumpPtr{opExtCodeCopy, true}
+	jumpTable[GASPRICE] = jumpPtr{opGasprice, true}
+	jumpTable[BLOCKHASH] = jumpPtr{opBlockhash, true}
+	jumpTable[COINBASE] = jumpPtr{opCoinbase, true}
+	jumpTable[TIMESTAMP] = jumpPtr{opTimestamp, true}
+	jumpTable[NUMBER] = jumpPtr{opNumber, true}
+	jumpTable[DIFFICULTY] = jumpPtr{opDifficulty, true}
+	jumpTable[GASLIMIT] = jumpPtr{opGasLimit, true}
+	jumpTable[POP] = jumpPtr{opPop, true}
+	jumpTable[MLOAD] = jumpPtr{opMload, true}
+	jumpTable[MSTORE] = jumpPtr{opMstore, true}
+	jumpTable[MSTORE8] = jumpPtr{opMstore8, true}
+	jumpTable[SLOAD] = jumpPtr{opSload, true}
+	jumpTable[SSTORE] = jumpPtr{opSstore, true}
+	jumpTable[JUMPDEST] = jumpPtr{opJumpdest, true}
+	jumpTable[PC] = jumpPtr{nil, true}
+	jumpTable[MSIZE] = jumpPtr{opMsize, true}
+	jumpTable[GAS] = jumpPtr{opGas, true}
+	jumpTable[CREATE] = jumpPtr{opCreate, true}
+	jumpTable[CALL] = jumpPtr{opCall, true}
+	jumpTable[CALLCODE] = jumpPtr{opCallCode, true}
+	jumpTable[LOG0] = jumpPtr{makeLog(0), true}
+	jumpTable[LOG1] = jumpPtr{makeLog(1), true}
+	jumpTable[LOG2] = jumpPtr{makeLog(2), true}
+	jumpTable[LOG3] = jumpPtr{makeLog(3), true}
+	jumpTable[LOG4] = jumpPtr{makeLog(4), true}
+	jumpTable[SWAP1] = jumpPtr{makeSwap(1), true}
+	jumpTable[SWAP2] = jumpPtr{makeSwap(2), true}
+	jumpTable[SWAP3] = jumpPtr{makeSwap(3), true}
+	jumpTable[SWAP4] = jumpPtr{makeSwap(4), true}
+	jumpTable[SWAP5] = jumpPtr{makeSwap(5), true}
+	jumpTable[SWAP6] = jumpPtr{makeSwap(6), true}
+	jumpTable[SWAP7] = jumpPtr{makeSwap(7), true}
+	jumpTable[SWAP8] = jumpPtr{makeSwap(8), true}
+	jumpTable[SWAP9] = jumpPtr{makeSwap(9), true}
+	jumpTable[SWAP10] = jumpPtr{makeSwap(10), true}
+	jumpTable[SWAP11] = jumpPtr{makeSwap(11), true}
+	jumpTable[SWAP12] = jumpPtr{makeSwap(12), true}
+	jumpTable[SWAP13] = jumpPtr{makeSwap(13), true}
+	jumpTable[SWAP14] = jumpPtr{makeSwap(14), true}
+	jumpTable[SWAP15] = jumpPtr{makeSwap(15), true}
+	jumpTable[SWAP16] = jumpPtr{makeSwap(16), true}
+	jumpTable[PUSH1] = jumpPtr{makePush(1, big.NewInt(1)), true}
+	jumpTable[PUSH2] = jumpPtr{makePush(2, big.NewInt(2)), true}
+	jumpTable[PUSH3] = jumpPtr{makePush(3, big.NewInt(3)), true}
+	jumpTable[PUSH4] = jumpPtr{makePush(4, big.NewInt(4)), true}
+	jumpTable[PUSH5] = jumpPtr{makePush(5, big.NewInt(5)), true}
+	jumpTable[PUSH6] = jumpPtr{makePush(6, big.NewInt(6)), true}
+	jumpTable[PUSH7] = jumpPtr{makePush(7, big.NewInt(7)), true}
+	jumpTable[PUSH8] = jumpPtr{makePush(8, big.NewInt(8)), true}
+	jumpTable[PUSH9] = jumpPtr{makePush(9, big.NewInt(9)), true}
+	jumpTable[PUSH10] = jumpPtr{makePush(10, big.NewInt(10)), true}
+	jumpTable[PUSH11] = jumpPtr{makePush(11, big.NewInt(11)), true}
+	jumpTable[PUSH12] = jumpPtr{makePush(12, big.NewInt(12)), true}
+	jumpTable[PUSH13] = jumpPtr{makePush(13, big.NewInt(13)), true}
+	jumpTable[PUSH14] = jumpPtr{makePush(14, big.NewInt(14)), true}
+	jumpTable[PUSH15] = jumpPtr{makePush(15, big.NewInt(15)), true}
+	jumpTable[PUSH16] = jumpPtr{makePush(16, big.NewInt(16)), true}
+	jumpTable[PUSH17] = jumpPtr{makePush(17, big.NewInt(17)), true}
+	jumpTable[PUSH18] = jumpPtr{makePush(18, big.NewInt(18)), true}
+	jumpTable[PUSH19] = jumpPtr{makePush(19, big.NewInt(19)), true}
+	jumpTable[PUSH20] = jumpPtr{makePush(20, big.NewInt(20)), true}
+	jumpTable[PUSH21] = jumpPtr{makePush(21, big.NewInt(21)), true}
+	jumpTable[PUSH22] = jumpPtr{makePush(22, big.NewInt(22)), true}
+	jumpTable[PUSH23] = jumpPtr{makePush(23, big.NewInt(23)), true}
+	jumpTable[PUSH24] = jumpPtr{makePush(24, big.NewInt(24)), true}
+	jumpTable[PUSH25] = jumpPtr{makePush(25, big.NewInt(25)), true}
+	jumpTable[PUSH26] = jumpPtr{makePush(26, big.NewInt(26)), true}
+	jumpTable[PUSH27] = jumpPtr{makePush(27, big.NewInt(27)), true}
+	jumpTable[PUSH28] = jumpPtr{makePush(28, big.NewInt(28)), true}
+	jumpTable[PUSH29] = jumpPtr{makePush(29, big.NewInt(29)), true}
+	jumpTable[PUSH30] = jumpPtr{makePush(30, big.NewInt(30)), true}
+	jumpTable[PUSH31] = jumpPtr{makePush(31, big.NewInt(31)), true}
+	jumpTable[PUSH32] = jumpPtr{makePush(32, big.NewInt(32)), true}
+	jumpTable[DUP1] = jumpPtr{makeDup(1), true}
+	jumpTable[DUP2] = jumpPtr{makeDup(2), true}
+	jumpTable[DUP3] = jumpPtr{makeDup(3), true}
+	jumpTable[DUP4] = jumpPtr{makeDup(4), true}
+	jumpTable[DUP5] = jumpPtr{makeDup(5), true}
+	jumpTable[DUP6] = jumpPtr{makeDup(6), true}
+	jumpTable[DUP7] = jumpPtr{makeDup(7), true}
+	jumpTable[DUP8] = jumpPtr{makeDup(8), true}
+	jumpTable[DUP9] = jumpPtr{makeDup(9), true}
+	jumpTable[DUP10] = jumpPtr{makeDup(10), true}
+	jumpTable[DUP11] = jumpPtr{makeDup(11), true}
+	jumpTable[DUP12] = jumpPtr{makeDup(12), true}
+	jumpTable[DUP13] = jumpPtr{makeDup(13), true}
+	jumpTable[DUP14] = jumpPtr{makeDup(14), true}
+	jumpTable[DUP15] = jumpPtr{makeDup(15), true}
+	jumpTable[DUP16] = jumpPtr{makeDup(16), true}
+
+	jumpTable[RETURN] = jumpPtr{nil, true}
+	jumpTable[SUICIDE] = jumpPtr{nil, true}
+	jumpTable[JUMP] = jumpPtr{nil, true}
+	jumpTable[JUMPI] = jumpPtr{nil, true}
+	jumpTable[STOP] = jumpPtr{nil, true}
+}
diff --git a/core/state/log.go b/core/vm/log.go
index 5d7d7357d..354f0ad35 100644
--- a/core/state/log.go
+++ b/core/vm/log.go
@@ -14,7 +14,7 @@
 // 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 state
+package vm
 
 import (
 	"fmt"
diff --git a/core/vm/logger.go b/core/vm/logger.go
index 736f595f6..2bd02319f 100644
--- a/core/vm/logger.go
+++ b/core/vm/logger.go
@@ -24,6 +24,7 @@ import (
 	"github.com/ethereum/go-ethereum/common"
 )
 
+// 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))
 	for _, log := range logs {
diff --git a/core/vm/memory.go b/core/vm/memory.go
index 0109050d7..101ec75cb 100644
--- a/core/vm/memory.go
+++ b/core/vm/memory.go
@@ -18,6 +18,7 @@ package vm
 
 import "fmt"
 
+// Memory implements ethereum RAM backed by a simple byte slice
 type Memory struct {
 	store []byte
 }
@@ -26,6 +27,7 @@ func NewMemory() *Memory {
 	return &Memory{nil}
 }
 
+// Set sets offset + size to value
 func (m *Memory) Set(offset, size uint64, value []byte) {
 	// length of store may never be less than offset + size.
 	// The store should be resized PRIOR to setting the memory
@@ -40,12 +42,14 @@ func (m *Memory) Set(offset, size uint64, value []byte) {
 	}
 }
 
+// Resize resizes the memory to size
 func (m *Memory) Resize(size uint64) {
 	if uint64(m.Len()) < size {
 		m.store = append(m.store, make([]byte, size-uint64(m.Len()))...)
 	}
 }
 
+// Get returns offset + size as a new slice
 func (self *Memory) Get(offset, size int64) (cpy []byte) {
 	if size == 0 {
 		return nil
@@ -61,6 +65,7 @@ func (self *Memory) Get(offset, size int64) (cpy []byte) {
 	return
 }
 
+// GetPtr returns the offset + size
 func (self *Memory) GetPtr(offset, size int64) []byte {
 	if size == 0 {
 		return nil
@@ -73,10 +78,12 @@ func (self *Memory) GetPtr(offset, size int64) []byte {
 	return nil
 }
 
+// Len returns the length of the backing slice
 func (m *Memory) Len() int {
 	return len(m.store)
 }
 
+// Data returns the backing slice
 func (m *Memory) Data() []byte {
 	return m.store
 }
diff --git a/core/vm/opcodes.go b/core/vm/opcodes.go
index ecced3650..986c35ef8 100644
--- a/core/vm/opcodes.go
+++ b/core/vm/opcodes.go
@@ -20,9 +20,9 @@ import (
 	"fmt"
 )
 
+// OpCode is an EVM opcode
 type OpCode byte
 
-// Op codes
 const (
 	// 0x0 range - arithmetic ops
 	STOP OpCode = iota
diff --git a/core/vm/virtual_machine.go b/core/vm/virtual_machine.go
index 047723744..9b3340bb2 100644
--- a/core/vm/virtual_machine.go
+++ b/core/vm/virtual_machine.go
@@ -16,7 +16,8 @@
 
 package vm
 
+// VirtualMachine is an EVM interface
 type VirtualMachine interface {
 	Env() Environment
-	Run(context *Context, data []byte) ([]byte, error)
+	Run(*Contract, []byte) ([]byte, error)
 }
diff --git a/core/vm/vm.go b/core/vm/vm.go
index d9e1a0ce5..57dd4dac3 100644
--- a/core/vm/vm.go
+++ b/core/vm/vm.go
@@ -14,33 +14,32 @@
 // 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 implements the Ethereum Virtual Machine.
 package vm
 
 import (
 	"fmt"
 	"math/big"
+	"time"
 
 	"github.com/ethereum/go-ethereum/common"
-	"github.com/ethereum/go-ethereum/core/state"
 	"github.com/ethereum/go-ethereum/crypto"
 	"github.com/ethereum/go-ethereum/logger"
 	"github.com/ethereum/go-ethereum/logger/glog"
 	"github.com/ethereum/go-ethereum/params"
 )
 
-// Vm implements VirtualMachine
+// Vm is an EVM and implements VirtualMachine
 type Vm struct {
 	env Environment
 }
 
-// New returns a new Virtual Machine
+// New returns a new Vm
 func New(env Environment) *Vm {
 	return &Vm{env: env}
 }
 
 // Run loops and evaluates the contract's code with the given input data
-func (self *Vm) Run(context *Context, input []byte) (ret []byte, err error) {
+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)
 
@@ -48,42 +47,48 @@ func (self *Vm) Run(context *Context, input []byte) (ret []byte, err error) {
 	defer func() {
 		if err != nil {
 			// In case of a VM exception (known exceptions) all gas consumed (panics NOT included).
-			context.UseGas(context.Gas)
+			contract.UseGas(contract.Gas)
 
-			ret = context.Return(nil)
+			ret = contract.Return(nil)
 		}
 	}()
 
-	if context.CodeAddr != nil {
-		if p := Precompiled[context.CodeAddr.Str()]; p != nil {
-			return self.RunPrecompiled(p, input, context)
+	if contract.CodeAddr != nil {
+		if p := Precompiled[contract.CodeAddr.Str()]; p != nil {
+			return self.RunPrecompiled(p, input, contract)
 		}
 	}
 
+	// Don't bother with the execution if there's no code.
+	if len(contract.Code) == 0 {
+		return contract.Return(nil), nil
+	}
+
 	var (
-		codehash = crypto.Sha3Hash(context.Code) // codehash is used when doing jump dest caching
+		codehash = crypto.Sha3Hash(contract.Code) // codehash is used when doing jump dest caching
 		program  *Program
 	)
 	if EnableJit {
-		// Fetch program status.
-		// * If ready run using JIT
-		// * If unknown, compile in a seperate goroutine
-		// * If forced wait for compilation and run once done
-		if status := GetProgramStatus(codehash); status == progReady {
-			return RunProgram(GetProgram(codehash), self.env, context, input)
-		} else if status == progUnknown {
+		// If the JIT is enabled check the status of the JIT program,
+		// if it doesn't exist compile a new program in a seperate
+		// 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)
+		case progUnknown:
 			if ForceJit {
 				// Create and compile program
-				program = NewProgram(context.Code)
+				program = NewProgram(contract.Code)
 				perr := CompileProgram(program)
 				if perr == nil {
-					return RunProgram(program, self.env, context, input)
+					return RunProgram(program, self.env, contract, input)
 				}
 				glog.V(logger.Info).Infoln("error compiling program", err)
 			} else {
 				// create and compile the program. Compilation
 				// is done in a seperate goroutine
-				program = NewProgram(context.Code)
+				program = NewProgram(contract.Code)
 				go func() {
 					err := CompileProgram(program)
 					if err != nil {
@@ -96,15 +101,14 @@ func (self *Vm) Run(context *Context, input []byte) (ret []byte, err error) {
 	}
 
 	var (
-		caller = context.caller
-		code   = context.Code
-		value  = context.value
-		price  = context.Price
-
-		op      OpCode             // current opcode
-		mem     = NewMemory()      // bound memory
-		stack   = newstack()       // local stack
-		statedb = self.env.State() // current state
+		caller     = contract.caller
+		code       = contract.Code
+		instrCount = 0
+
+		op      OpCode          // current opcode
+		mem     = NewMemory()   // bound memory
+		stack   = newstack()    // local stack
+		statedb = self.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. Pratically much less so feasible.
 		pc = uint64(0) // program counter
@@ -112,8 +116,8 @@ func (self *Vm) Run(context *Context, input []byte) (ret []byte, err error) {
 		// jump evaluates and checks whether the given jump destination is a valid one
 		// if valid move the `pc` otherwise return an error.
 		jump = func(from uint64, to *big.Int) error {
-			if !context.jumpdests.has(codehash, code, to) {
-				nop := context.GetOp(to.Uint64())
+			if !contract.jumpdests.has(codehash, code, to) {
+				nop := contract.GetOp(to.Uint64())
 				return fmt.Errorf("invalid jump destination (%v) %v", nop, to)
 			}
 
@@ -125,552 +129,92 @@ func (self *Vm) Run(context *Context, input []byte) (ret []byte, err error) {
 		newMemSize *big.Int
 		cost       *big.Int
 	)
+	contract.Input = input
 
 	// 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, context.Gas, cost, mem, stack, context, err)
+			self.log(pc, op, contract.Gas, cost, mem, stack, contract, err)
 		}
 	}()
 
-	// Don't bother with the execution if there's no code.
-	if len(code) == 0 {
-		return context.Return(nil), nil
+	if glog.V(logger.Debug) {
+		glog.Infof("running byte VM %x\n", codehash[:4])
+		tstart := time.Now()
+		defer func() {
+			glog.Infof("byte VM %x done. time: %v instrc: %v\n", codehash[:4], time.Since(tstart), instrCount)
+		}()
 	}
 
-	for {
-		// Overhead of the atomic read might not be worth it
-		/* TODO this still causes a few issues in the tests
-		if program != nil && progStatus(atomic.LoadInt32(&program.status)) == progReady {
-			// move execution
-			glog.V(logger.Info).Infoln("Moved execution to JIT")
-			return runProgram(program, pc, mem, stack, self.env, context, input)
-		}
+	for ; ; instrCount++ {
+		/*
+			if EnableJit && it%100 == 0 {
+				if program != nil && progStatus(atomic.LoadInt32(&program.status)) == progReady {
+					// 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)
+				}
+			}
 		*/
-		// The base for all big integer arithmetic
-		base := new(big.Int)
 
 		// Get the memory location of pc
-		op = context.GetOp(pc)
+		op = contract.GetOp(pc)
 
 		// calculate the new memory size and gas price for the current executing opcode
-		newMemSize, cost, err = calculateGasAndSize(self.env, context, caller, op, statedb, mem, stack)
+		newMemSize, cost, err = calculateGasAndSize(self.env, contract, caller, op, statedb, mem, stack)
 		if err != nil {
 			return nil, err
 		}
 
 		// Use the calculated gas. When insufficient gas is present, use all gas and return an
 		// Out Of Gas error
-		if !context.UseGas(cost) {
+		if !contract.UseGas(cost) {
 			return nil, OutOfGasError
 		}
 
 		// Resize the memory calculated previously
 		mem.Resize(newMemSize.Uint64())
 		// Add a log message
-		self.log(pc, op, context.Gas, cost, mem, stack, context, nil)
-
-		switch op {
-		case ADD:
-			x, y := stack.pop(), stack.pop()
-
-			base.Add(x, y)
-
-			U256(base)
-
-			// pop result back on the stack
-			stack.push(base)
-		case SUB:
-			x, y := stack.pop(), stack.pop()
-
-			base.Sub(x, y)
-
-			U256(base)
-
-			// pop result back on the stack
-			stack.push(base)
-		case MUL:
-			x, y := stack.pop(), stack.pop()
-
-			base.Mul(x, y)
-
-			U256(base)
-
-			// pop result back on the stack
-			stack.push(base)
-		case DIV:
-			x, y := stack.pop(), stack.pop()
-
-			if y.Cmp(common.Big0) != 0 {
-				base.Div(x, y)
-			}
-
-			U256(base)
-
-			// pop result back on the stack
-			stack.push(base)
-		case SDIV:
-			x, y := S256(stack.pop()), S256(stack.pop())
-
-			if y.Cmp(common.Big0) == 0 {
-				base.Set(common.Big0)
-			} else {
-				n := new(big.Int)
-				if new(big.Int).Mul(x, y).Cmp(common.Big0) < 0 {
-					n.SetInt64(-1)
-				} else {
-					n.SetInt64(1)
-				}
-
-				base.Div(x.Abs(x), y.Abs(y)).Mul(base, n)
-
-				U256(base)
-			}
-
-			stack.push(base)
-		case MOD:
-			x, y := stack.pop(), stack.pop()
-
-			if y.Cmp(common.Big0) == 0 {
-				base.Set(common.Big0)
-			} else {
-				base.Mod(x, y)
-			}
-
-			U256(base)
-
-			stack.push(base)
-		case SMOD:
-			x, y := S256(stack.pop()), S256(stack.pop())
-
-			if y.Cmp(common.Big0) == 0 {
-				base.Set(common.Big0)
-			} else {
-				n := new(big.Int)
-				if x.Cmp(common.Big0) < 0 {
-					n.SetInt64(-1)
-				} else {
-					n.SetInt64(1)
-				}
-
-				base.Mod(x.Abs(x), y.Abs(y)).Mul(base, n)
-
-				U256(base)
-			}
-
-			stack.push(base)
-
-		case EXP:
-			x, y := stack.pop(), stack.pop()
-
-			base.Exp(x, y, Pow256)
-
-			U256(base)
-
-			stack.push(base)
-		case SIGNEXTEND:
-			back := stack.pop()
-			if back.Cmp(big.NewInt(31)) < 0 {
-				bit := uint(back.Uint64()*8 + 7)
-				num := stack.pop()
-				mask := new(big.Int).Lsh(common.Big1, bit)
-				mask.Sub(mask, common.Big1)
-				if common.BitTest(num, int(bit)) {
-					num.Or(num, mask.Not(mask))
-				} else {
-					num.And(num, mask)
-				}
-
-				num = U256(num)
-
-				stack.push(num)
-			}
-		case NOT:
-			stack.push(U256(new(big.Int).Not(stack.pop())))
-		case LT:
-			x, y := stack.pop(), stack.pop()
-
-			// x < y
-			if x.Cmp(y) < 0 {
-				stack.push(common.BigTrue)
-			} else {
-				stack.push(common.BigFalse)
-			}
-		case GT:
-			x, y := stack.pop(), stack.pop()
-
-			// x > y
-			if x.Cmp(y) > 0 {
-				stack.push(common.BigTrue)
-			} else {
-				stack.push(common.BigFalse)
-			}
-
-		case SLT:
-			x, y := S256(stack.pop()), S256(stack.pop())
-
-			// x < y
-			if x.Cmp(S256(y)) < 0 {
-				stack.push(common.BigTrue)
-			} else {
-				stack.push(common.BigFalse)
-			}
-		case SGT:
-			x, y := S256(stack.pop()), S256(stack.pop())
-
-			// x > y
-			if x.Cmp(y) > 0 {
-				stack.push(common.BigTrue)
-			} else {
-				stack.push(common.BigFalse)
-			}
-
-		case EQ:
-			x, y := stack.pop(), stack.pop()
-
-			// x == y
-			if x.Cmp(y) == 0 {
-				stack.push(common.BigTrue)
-			} else {
-				stack.push(common.BigFalse)
-			}
-		case ISZERO:
-			x := stack.pop()
-			if x.Cmp(common.BigFalse) > 0 {
-				stack.push(common.BigFalse)
-			} else {
-				stack.push(common.BigTrue)
-			}
-
-		case AND:
-			x, y := stack.pop(), stack.pop()
-
-			stack.push(base.And(x, y))
-		case OR:
-			x, y := stack.pop(), stack.pop()
-
-			stack.push(base.Or(x, y))
-		case XOR:
-			x, y := stack.pop(), stack.pop()
-
-			stack.push(base.Xor(x, y))
-		case BYTE:
-			th, val := stack.pop(), stack.pop()
-
-			if th.Cmp(big.NewInt(32)) < 0 {
-				byt := big.NewInt(int64(common.LeftPadBytes(val.Bytes(), 32)[th.Int64()]))
-
-				base.Set(byt)
-			} else {
-				base.Set(common.BigFalse)
-			}
-
-			stack.push(base)
-		case ADDMOD:
-			x := stack.pop()
-			y := stack.pop()
-			z := stack.pop()
-
-			if z.Cmp(Zero) > 0 {
-				add := new(big.Int).Add(x, y)
-				base.Mod(add, z)
-
-				base = U256(base)
-			}
-
-			stack.push(base)
-		case MULMOD:
-			x := stack.pop()
-			y := stack.pop()
-			z := stack.pop()
-
-			if z.Cmp(Zero) > 0 {
-				mul := new(big.Int).Mul(x, y)
-				base.Mod(mul, z)
-
-				U256(base)
-			}
-
-			stack.push(base)
-
-		case SHA3:
-			offset, size := stack.pop(), stack.pop()
-			data := crypto.Sha3(mem.Get(offset.Int64(), size.Int64()))
-
-			stack.push(common.BigD(data))
+		self.log(pc, op, contract.Gas, cost, mem, stack, contract, nil)
 
-		case ADDRESS:
-			stack.push(common.Bytes2Big(context.Address().Bytes()))
-
-		case BALANCE:
-			addr := common.BigToAddress(stack.pop())
-			balance := statedb.GetBalance(addr)
-
-			stack.push(new(big.Int).Set(balance))
-
-		case ORIGIN:
-			origin := self.env.Origin()
-
-			stack.push(origin.Big())
-
-		case CALLER:
-			caller := context.caller.Address()
-			stack.push(common.Bytes2Big(caller.Bytes()))
-
-		case CALLVALUE:
-			stack.push(new(big.Int).Set(value))
-
-		case CALLDATALOAD:
-			data := getData(input, stack.pop(), common.Big32)
-
-			stack.push(common.Bytes2Big(data))
-		case CALLDATASIZE:
-			l := int64(len(input))
-			stack.push(big.NewInt(l))
-
-		case CALLDATACOPY:
-			var (
-				mOff = stack.pop()
-				cOff = stack.pop()
-				l    = stack.pop()
-			)
-			data := getData(input, cOff, l)
-
-			mem.Set(mOff.Uint64(), l.Uint64(), data)
-
-		case CODESIZE, EXTCODESIZE:
-			var code []byte
-			if op == EXTCODESIZE {
-				addr := common.BigToAddress(stack.pop())
-
-				code = statedb.GetCode(addr)
-			} else {
-				code = context.Code
-			}
-
-			l := big.NewInt(int64(len(code)))
-			stack.push(l)
-
-		case CODECOPY, EXTCODECOPY:
-			var code []byte
-			if op == EXTCODECOPY {
-				addr := common.BigToAddress(stack.pop())
-				code = statedb.GetCode(addr)
+		if opPtr := jumpTable[op]; opPtr.valid {
+			if opPtr.fn != nil {
+				opPtr.fn(instruction{}, &pc, self.env, contract, mem, stack)
 			} else {
-				code = context.Code
-			}
-
-			var (
-				mOff = stack.pop()
-				cOff = stack.pop()
-				l    = stack.pop()
-			)
-
-			codeCopy := getData(code, cOff, l)
-
-			mem.Set(mOff.Uint64(), l.Uint64(), codeCopy)
-
-		case GASPRICE:
-			stack.push(new(big.Int).Set(context.Price))
-
-		case BLOCKHASH:
-			num := stack.pop()
-
-			n := new(big.Int).Sub(self.env.BlockNumber(), common.Big257)
-			if num.Cmp(n) > 0 && num.Cmp(self.env.BlockNumber()) < 0 {
-				stack.push(self.env.GetHash(num.Uint64()).Big())
-			} else {
-				stack.push(common.Big0)
-			}
-
-		case COINBASE:
-			coinbase := self.env.Coinbase()
-
-			stack.push(coinbase.Big())
-
-		case TIMESTAMP:
-			time := self.env.Time()
-
-			stack.push(new(big.Int).Set(time))
-
-		case NUMBER:
-			number := self.env.BlockNumber()
-
-			stack.push(U256(number))
-
-		case DIFFICULTY:
-			difficulty := self.env.Difficulty()
-
-			stack.push(new(big.Int).Set(difficulty))
-
-		case GASLIMIT:
-
-			stack.push(new(big.Int).Set(self.env.GasLimit()))
-
-		case PUSH1, PUSH2, PUSH3, PUSH4, PUSH5, PUSH6, PUSH7, PUSH8, PUSH9, PUSH10, PUSH11, PUSH12, PUSH13, PUSH14, PUSH15, PUSH16, PUSH17, PUSH18, PUSH19, PUSH20, PUSH21, PUSH22, PUSH23, PUSH24, PUSH25, PUSH26, PUSH27, PUSH28, PUSH29, PUSH30, PUSH31, PUSH32:
-			size := uint64(op - PUSH1 + 1)
-			byts := getData(code, new(big.Int).SetUint64(pc+1), new(big.Int).SetUint64(size))
-			// push value to stack
-			stack.push(common.Bytes2Big(byts))
-			pc += size
-
-		case POP:
-			stack.pop()
-		case DUP1, DUP2, DUP3, DUP4, DUP5, DUP6, DUP7, DUP8, DUP9, DUP10, DUP11, DUP12, DUP13, DUP14, DUP15, DUP16:
-			n := int(op - DUP1 + 1)
-			stack.dup(n)
-
-		case SWAP1, SWAP2, SWAP3, SWAP4, SWAP5, SWAP6, SWAP7, SWAP8, SWAP9, SWAP10, SWAP11, SWAP12, SWAP13, SWAP14, SWAP15, SWAP16:
-			n := int(op - SWAP1 + 2)
-			stack.swap(n)
-
-		case LOG0, LOG1, LOG2, LOG3, LOG4:
-			n := int(op - LOG0)
-			topics := make([]common.Hash, n)
-			mStart, mSize := stack.pop(), stack.pop()
-			for i := 0; i < n; i++ {
-				topics[i] = common.BigToHash(stack.pop())
-			}
-
-			data := mem.Get(mStart.Int64(), mSize.Int64())
-			log := state.NewLog(context.Address(), topics, data, self.env.BlockNumber().Uint64())
-			self.env.AddLog(log)
-
-		case MLOAD:
-			offset := stack.pop()
-			val := common.BigD(mem.Get(offset.Int64(), 32))
-			stack.push(val)
-
-		case MSTORE:
-			// pop value of the stack
-			mStart, val := stack.pop(), stack.pop()
-			mem.Set(mStart.Uint64(), 32, common.BigToBytes(val, 256))
-
-		case MSTORE8:
-			off, val := stack.pop().Int64(), stack.pop().Int64()
-
-			mem.store[off] = byte(val & 0xff)
-
-		case SLOAD:
-			loc := common.BigToHash(stack.pop())
-			val := statedb.GetState(context.Address(), loc).Big()
-			stack.push(val)
+				switch op {
+				case PC:
+					opPc(instruction{data: new(big.Int).SetUint64(pc)}, &pc, self.env, contract, mem, stack)
+				case JUMP:
+					if err := jump(pc, stack.pop()); err != nil {
+						return nil, err
+					}
 
-		case SSTORE:
-			loc := common.BigToHash(stack.pop())
-			val := stack.pop()
+					continue
+				case JUMPI:
+					pos, cond := stack.pop(), stack.pop()
 
-			statedb.SetState(context.Address(), loc, common.BigToHash(val))
+					if cond.Cmp(common.BigTrue) >= 0 {
+						if err := jump(pc, pos); err != nil {
+							return nil, err
+						}
 
-		case JUMP:
-			if err := jump(pc, stack.pop()); err != nil {
-				return nil, err
-			}
+						continue
+					}
+				case RETURN:
+					offset, size := stack.pop(), stack.pop()
+					ret := mem.GetPtr(offset.Int64(), size.Int64())
 
-			continue
-		case JUMPI:
-			pos, cond := stack.pop(), stack.pop()
+					return contract.Return(ret), nil
+				case SUICIDE:
+					opSuicide(instruction{}, nil, self.env, contract, mem, stack)
 
-			if cond.Cmp(common.BigTrue) >= 0 {
-				if err := jump(pc, pos); err != nil {
-					return nil, err
+					fallthrough
+				case STOP: // Stop the contract
+					return contract.Return(nil), nil
 				}
-
-				continue
-			}
-
-		case JUMPDEST:
-		case PC:
-			stack.push(new(big.Int).SetUint64(pc))
-		case MSIZE:
-			stack.push(big.NewInt(int64(mem.Len())))
-		case GAS:
-			stack.push(new(big.Int).Set(context.Gas))
-		case CREATE:
-
-			var (
-				value        = stack.pop()
-				offset, size = stack.pop(), stack.pop()
-				input        = mem.Get(offset.Int64(), size.Int64())
-				gas          = new(big.Int).Set(context.Gas)
-				addr         common.Address
-			)
-
-			context.UseGas(context.Gas)
-			ret, suberr, ref := self.env.Create(context, input, gas, price, value)
-			if suberr != nil {
-				stack.push(common.BigFalse)
-
-			} else {
-				// gas < len(ret) * CreateDataGas == NO_CODE
-				dataGas := big.NewInt(int64(len(ret)))
-				dataGas.Mul(dataGas, params.CreateDataGas)
-				if context.UseGas(dataGas) {
-					ref.SetCode(ret)
-				}
-				addr = ref.Address()
-
-				stack.push(addr.Big())
-
-			}
-
-		case CALL, CALLCODE:
-			gas := stack.pop()
-			// pop gas and value of the stack.
-			addr, value := stack.pop(), stack.pop()
-			value = U256(value)
-			// pop input size and offset
-			inOffset, inSize := stack.pop(), stack.pop()
-			// pop return size and offset
-			retOffset, retSize := stack.pop(), stack.pop()
-
-			address := common.BigToAddress(addr)
-
-			// Get the arguments from the memory
-			args := mem.Get(inOffset.Int64(), inSize.Int64())
-
-			if len(value.Bytes()) > 0 {
-				gas.Add(gas, params.CallStipend)
-			}
-
-			var (
-				ret []byte
-				err error
-			)
-			if op == CALLCODE {
-				ret, err = self.env.CallCode(context, address, args, gas, price, value)
-			} else {
-				ret, err = self.env.Call(context, address, args, gas, price, value)
-			}
-
-			if err != nil {
-				stack.push(common.BigFalse)
-
-			} else {
-				stack.push(common.BigTrue)
-
-				mem.Set(retOffset.Uint64(), retSize.Uint64(), ret)
 			}
-
-		case RETURN:
-			offset, size := stack.pop(), stack.pop()
-			ret := mem.GetPtr(offset.Int64(), size.Int64())
-
-			return context.Return(ret), nil
-		case SUICIDE:
-			receiver := statedb.GetOrNewStateObject(common.BigToAddress(stack.pop()))
-			balance := statedb.GetBalance(context.Address())
-
-			receiver.AddBalance(balance)
-
-			statedb.Delete(context.Address())
-
-			fallthrough
-		case STOP: // Stop the context
-
-			return context.Return(nil), nil
-		default:
-
+		} else {
 			return nil, fmt.Errorf("Invalid opcode %x", op)
 		}
 
@@ -681,7 +225,7 @@ func (self *Vm) Run(context *Context, input []byte) (ret []byte, err error) {
 
 // calculateGasAndSize calculates the required given the opcode and stack items calculates the new memorysize for
 // the operation. This does not reduce gas or resizes the memory.
-func calculateGasAndSize(env Environment, context *Context, caller ContextRef, op OpCode, statedb *state.StateDB, mem *Memory, stack *stack) (*big.Int, *big.Int, error) {
+func calculateGasAndSize(env Environment, contract *Contract, caller ContractRef, op OpCode, statedb Database, mem *Memory, stack *stack) (*big.Int, *big.Int, error) {
 	var (
 		gas                 = new(big.Int)
 		newMemSize *big.Int = new(big.Int)
@@ -731,7 +275,7 @@ func calculateGasAndSize(env Environment, context *Context, caller ContextRef, o
 
 		var g *big.Int
 		y, x := stack.data[stack.len()-2], stack.data[stack.len()-1]
-		val := statedb.GetState(context.Address(), common.BigToHash(x))
+		val := statedb.GetState(contract.Address(), common.BigToHash(x))
 
 		// This checks for 3 scenario's and calculates gas accordingly
 		// 1. From a zero-value address to a non-zero value         (NEW VALUE)
@@ -741,7 +285,7 @@ func calculateGasAndSize(env Environment, context *Context, caller ContextRef, o
 			// 0 => non 0
 			g = params.SstoreSetGas
 		} else if !common.EmptyHash(val) && common.EmptyHash(common.BigToHash(y)) {
-			statedb.Refund(params.SstoreRefundGas)
+			statedb.AddRefund(params.SstoreRefundGas)
 
 			g = params.SstoreClearGas
 		} else {
@@ -750,8 +294,8 @@ func calculateGasAndSize(env Environment, context *Context, caller ContextRef, o
 		}
 		gas.Set(g)
 	case SUICIDE:
-		if !statedb.IsDeleted(context.Address()) {
-			statedb.Refund(params.SuicideRefundGas)
+		if !statedb.IsDeleted(contract.Address()) {
+			statedb.AddRefund(params.SuicideRefundGas)
 		}
 	case MLOAD:
 		newMemSize = calcMemSize(stack.peek(), u256(32))
@@ -788,7 +332,8 @@ func calculateGasAndSize(env Environment, context *Context, caller ContextRef, o
 		gas.Add(gas, stack.data[stack.len()-1])
 
 		if op == CALL {
-			if env.State().GetStateObject(common.BigToAddress(stack.data[stack.len()-2])) == nil {
+			//if env.Db().GetStateObject(common.BigToAddress(stack.data[stack.len()-2])) == nil {
+			if !env.Db().Exist(common.BigToAddress(stack.data[stack.len()-2])) {
 				gas.Add(gas, params.CallNewAccountGas)
 			}
 		}
@@ -802,38 +347,18 @@ func calculateGasAndSize(env Environment, context *Context, caller ContextRef, o
 
 		newMemSize = common.BigMax(x, y)
 	}
-
-	if newMemSize.Cmp(common.Big0) > 0 {
-		newMemSizeWords := toWordSize(newMemSize)
-		newMemSize.Mul(newMemSizeWords, u256(32))
-
-		if newMemSize.Cmp(u256(int64(mem.Len()))) > 0 {
-			oldSize := toWordSize(big.NewInt(int64(mem.Len())))
-			pow := new(big.Int).Exp(oldSize, common.Big2, Zero)
-			linCoef := new(big.Int).Mul(oldSize, params.MemoryGas)
-			quadCoef := new(big.Int).Div(pow, params.QuadCoeffDiv)
-			oldTotalFee := new(big.Int).Add(linCoef, quadCoef)
-
-			pow.Exp(newMemSizeWords, common.Big2, Zero)
-			linCoef = new(big.Int).Mul(newMemSizeWords, params.MemoryGas)
-			quadCoef = new(big.Int).Div(pow, params.QuadCoeffDiv)
-			newTotalFee := new(big.Int).Add(linCoef, quadCoef)
-
-			fee := new(big.Int).Sub(newTotalFee, oldTotalFee)
-			gas.Add(gas, fee)
-		}
-	}
+	quadMemGas(mem, newMemSize, gas)
 
 	return newMemSize, gas, nil
 }
 
 // RunPrecompile runs and evaluate the output of a precompiled contract defined in contracts.go
-func (self *Vm) RunPrecompiled(p *PrecompiledAccount, input []byte, context *Context) (ret []byte, err error) {
+func (self *Vm) RunPrecompiled(p *PrecompiledAccount, input []byte, contract *Contract) (ret []byte, err error) {
 	gas := p.Gas(len(input))
-	if context.UseGas(gas) {
+	if contract.UseGas(gas) {
 		ret = p.Call(input)
 
-		return context.Return(ret), nil
+		return contract.Return(ret), nil
 	} else {
 		return nil, OutOfGasError
 	}
@@ -841,18 +366,20 @@ func (self *Vm) RunPrecompiled(p *PrecompiledAccount, input []byte, context *Con
 
 // 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, context *Context, err error) {
+func (self *Vm) log(pc uint64, op OpCode, gas, cost *big.Int, memory *Memory, stack *stack, contract *Contract, err error) {
 	if Debug {
 		mem := make([]byte, len(memory.Data()))
 		copy(mem, memory.Data())
 		stck := make([]*big.Int, len(stack.Data()))
 		copy(stck, stack.Data())
 
-		object := context.self.(*state.StateObject)
 		storage := make(map[common.Hash][]byte)
-		object.EachStorage(func(k, v []byte) {
-			storage[common.BytesToHash(k)] = v
-		})
+		/*
+			object := contract.self.(*state.StateObject)
+			object.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})
 	}
diff --git a/core/vm/vm_jit.go b/core/vm/vm_jit.go
index 339cb8ea8..07cb52d4a 100644
--- a/core/vm/vm_jit.go
+++ b/core/vm/vm_jit.go
@@ -30,6 +30,7 @@ void  evmjit_destroy(void* _jit);
 */
 import "C"
 
+/*
 import (
 	"bytes"
 	"errors"
@@ -385,4 +386,4 @@ func env_extcode(_vm unsafe.Pointer, _addr unsafe.Pointer, o_size *uint64) *byte
 	code := vm.Env().State().GetCode(addr)
 	*o_size = uint64(len(code))
 	return getDataPtr(code)
-}
+}*/
diff --git a/core/vm_env.go b/core/vm_env.go
index a08f024fe..dea280746 100644
--- a/core/vm_env.go
+++ b/core/vm_env.go
@@ -53,7 +53,7 @@ func (self *VMEnv) Time() *big.Int           { return self.header.Time }
 func (self *VMEnv) Difficulty() *big.Int     { return self.header.Difficulty }
 func (self *VMEnv) GasLimit() *big.Int       { return self.header.GasLimit }
 func (self *VMEnv) Value() *big.Int          { return self.msg.Value() }
-func (self *VMEnv) State() *state.StateDB    { return self.state }
+func (self *VMEnv) Db() vm.Database          { return self.state }
 func (self *VMEnv) Depth() int               { return self.depth }
 func (self *VMEnv) SetDepth(i int)           { self.depth = i }
 func (self *VMEnv) VmType() vm.Type          { return self.typ }
@@ -66,30 +66,34 @@ func (self *VMEnv) GetHash(n uint64) common.Hash {
 	return common.Hash{}
 }
 
-func (self *VMEnv) AddLog(log *state.Log) {
+func (self *VMEnv) AddLog(log *vm.Log) {
 	self.state.AddLog(log)
 }
-func (self *VMEnv) CanTransfer(from vm.Account, balance *big.Int) bool {
-	return from.Balance().Cmp(balance) >= 0
+func (self *VMEnv) CanTransfer(from common.Address, balance *big.Int) bool {
+	return self.state.GetBalance(from).Cmp(balance) >= 0
+}
+
+func (self *VMEnv) MakeSnapshot() vm.Database {
+	return self.state.Copy()
+}
+
+func (self *VMEnv) SetSnapshot(copy vm.Database) {
+	self.state.Set(copy.(*state.StateDB))
 }
 
 func (self *VMEnv) Transfer(from, to vm.Account, amount *big.Int) error {
-	return vm.Transfer(from, to, amount)
+	return Transfer(from, to, amount)
 }
 
-func (self *VMEnv) Call(me vm.ContextRef, addr common.Address, data []byte, gas, price, value *big.Int) ([]byte, error) {
-	exe := NewExecution(self, &addr, data, gas, price, value)
-	return exe.Call(addr, me)
+func (self *VMEnv) Call(me vm.ContractRef, addr common.Address, data []byte, gas, price, value *big.Int) ([]byte, error) {
+	return Call(self, me, addr, data, gas, price, value)
 }
-func (self *VMEnv) CallCode(me vm.ContextRef, addr common.Address, data []byte, gas, price, value *big.Int) ([]byte, error) {
-	maddr := me.Address()
-	exe := NewExecution(self, &maddr, data, gas, price, value)
-	return exe.Call(addr, me)
+func (self *VMEnv) CallCode(me vm.ContractRef, addr common.Address, data []byte, gas, price, value *big.Int) ([]byte, error) {
+	return CallCode(self, me, addr, data, gas, price, value)
 }
 
-func (self *VMEnv) Create(me vm.ContextRef, data []byte, gas, price, value *big.Int) ([]byte, error, vm.ContextRef) {
-	exe := NewExecution(self, nil, data, gas, price, value)
-	return exe.Create(me)
+func (self *VMEnv) Create(me vm.ContractRef, data []byte, gas, price, value *big.Int) ([]byte, common.Address, error) {
+	return Create(self, me, data, gas, price, value)
 }
 
 func (self *VMEnv) StructLogs() []vm.StructLog {
diff --git a/eth/filters/filter.go b/eth/filters/filter.go
index b7f795607..0b4911629 100644
--- a/eth/filters/filter.go
+++ b/eth/filters/filter.go
@@ -21,8 +21,8 @@ import (
 
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/core"
-	"github.com/ethereum/go-ethereum/core/state"
 	"github.com/ethereum/go-ethereum/core/types"
+	"github.com/ethereum/go-ethereum/core/vm"
 )
 
 type AccountChange struct {
@@ -39,9 +39,9 @@ type Filter struct {
 	max      int
 	topics   [][]common.Hash
 
-	BlockCallback       func(*types.Block, state.Logs)
+	BlockCallback       func(*types.Block, vm.Logs)
 	TransactionCallback func(*types.Transaction)
-	LogsCallback        func(state.Logs)
+	LogsCallback        func(vm.Logs)
 }
 
 // Create a new filter which uses a bloom filter on blocks to figure out whether a particular block
@@ -78,7 +78,7 @@ func (self *Filter) SetSkip(skip int) {
 }
 
 // Run filters logs with the current parameters set
-func (self *Filter) Find() state.Logs {
+func (self *Filter) Find() vm.Logs {
 	earliestBlock := core.GetCurrentBlock(self.db)
 	var earliestBlockNo uint64 = uint64(self.earliest)
 	if self.earliest == -1 {
@@ -90,7 +90,7 @@ func (self *Filter) Find() state.Logs {
 	}
 
 	var (
-		logs  state.Logs
+		logs  vm.Logs
 		block = core.GetBlockByNumber(self.db, latestBlockNo)
 	)
 
@@ -112,7 +112,7 @@ done:
 			// Get the logs of the block
 			var (
 				receipts   = core.GetBlockReceipts(self.db, block.Hash())
-				unfiltered state.Logs
+				unfiltered vm.Logs
 			)
 			for _, receipt := range receipts {
 				unfiltered = append(unfiltered, receipt.Logs()...)
@@ -138,8 +138,8 @@ func includes(addresses []common.Address, a common.Address) bool {
 	return false
 }
 
-func (self *Filter) FilterLogs(logs state.Logs) state.Logs {
-	var ret state.Logs
+func (self *Filter) FilterLogs(logs vm.Logs) vm.Logs {
+	var ret vm.Logs
 
 	// Filter the logs for interesting stuff
 Logs:
diff --git a/eth/filters/filter_system.go b/eth/filters/filter_system.go
index 9ad73a896..1c27c7be4 100644
--- a/eth/filters/filter_system.go
+++ b/eth/filters/filter_system.go
@@ -22,7 +22,7 @@ import (
 	"sync"
 
 	"github.com/ethereum/go-ethereum/core"
-	"github.com/ethereum/go-ethereum/core/state"
+	"github.com/ethereum/go-ethereum/core/vm"
 	"github.com/ethereum/go-ethereum/event"
 )
 
@@ -89,7 +89,7 @@ func (fs *FilterSystem) filterLoop() {
 		//core.PendingBlockEvent{},
 		core.ChainEvent{},
 		core.TxPreEvent{},
-		state.Logs(nil))
+		vm.Logs(nil))
 
 out:
 	for {
@@ -116,7 +116,7 @@ out:
 				}
 				fs.filterMu.RUnlock()
 
-			case state.Logs:
+			case vm.Logs:
 				fs.filterMu.RLock()
 				for _, filter := range fs.filters {
 					if filter.LogsCallback != nil {
diff --git a/miner/worker.go b/miner/worker.go
index 098f42a72..470f1f676 100644
--- a/miner/worker.go
+++ b/miner/worker.go
@@ -29,6 +29,7 @@ import (
 	"github.com/ethereum/go-ethereum/core"
 	"github.com/ethereum/go-ethereum/core/state"
 	"github.com/ethereum/go-ethereum/core/types"
+	"github.com/ethereum/go-ethereum/core/vm"
 	"github.com/ethereum/go-ethereum/ethdb"
 	"github.com/ethereum/go-ethereum/event"
 	"github.com/ethereum/go-ethereum/logger"
@@ -298,7 +299,7 @@ func (self *worker) wait() {
 				}
 
 				// broadcast before waiting for validation
-				go func(block *types.Block, logs state.Logs, receipts []*types.Receipt) {
+				go func(block *types.Block, logs vm.Logs, receipts []*types.Receipt) {
 					self.mux.Post(core.NewMinedBlockEvent{block})
 					self.mux.Post(core.ChainEvent{block, block.Hash(), logs})
 					if stat == core.CanonStatTy {
diff --git a/rpc/api/eth_args.go b/rpc/api/eth_args.go
index 8bd077e20..66c190a51 100644
--- a/rpc/api/eth_args.go
+++ b/rpc/api/eth_args.go
@@ -24,8 +24,8 @@ import (
 	"strings"
 
 	"github.com/ethereum/go-ethereum/common"
-	"github.com/ethereum/go-ethereum/core/state"
 	"github.com/ethereum/go-ethereum/core/types"
+	"github.com/ethereum/go-ethereum/core/vm"
 	"github.com/ethereum/go-ethereum/rpc/shared"
 )
 
@@ -830,7 +830,7 @@ type LogRes struct {
 	TransactionIndex *hexnum    `json:"transactionIndex"`
 }
 
-func NewLogRes(log *state.Log) LogRes {
+func NewLogRes(log *vm.Log) LogRes {
 	var l LogRes
 	l.Topics = make([]*hexdata, len(log.Topics))
 	for j, topic := range log.Topics {
@@ -847,7 +847,7 @@ func NewLogRes(log *state.Log) LogRes {
 	return l
 }
 
-func NewLogsRes(logs state.Logs) (ls []LogRes) {
+func NewLogsRes(logs vm.Logs) (ls []LogRes) {
 	ls = make([]LogRes, len(logs))
 
 	for i, log := range logs {
diff --git a/tests/state_test_util.go b/tests/state_test_util.go
index 3d8dfca31..a1c066c82 100644
--- a/tests/state_test_util.go
+++ b/tests/state_test_util.go
@@ -168,7 +168,7 @@ func runStateTest(test VmTest) error {
 		ret []byte
 		// gas  *big.Int
 		// err  error
-		logs state.Logs
+		logs vm.Logs
 	)
 
 	ret, logs, _, _ = RunState(statedb, env, test.Transaction)
@@ -216,7 +216,7 @@ func runStateTest(test VmTest) error {
 	return nil
 }
 
-func RunState(statedb *state.StateDB, env, tx map[string]string) ([]byte, state.Logs, *big.Int, error) {
+func RunState(statedb *state.StateDB, env, tx map[string]string) ([]byte, vm.Logs, *big.Int, error) {
 	var (
 		data  = common.FromHex(tx["data"])
 		gas   = common.Big(tx["gasLimit"])
diff --git a/tests/util.go b/tests/util.go
index 72d927ada..fb9e518c8 100644
--- a/tests/util.go
+++ b/tests/util.go
@@ -30,7 +30,7 @@ import (
 	"github.com/ethereum/go-ethereum/ethdb"
 )
 
-func checkLogs(tlog []Log, logs state.Logs) error {
+func checkLogs(tlog []Log, logs vm.Logs) error {
 
 	if len(tlog) != len(logs) {
 		return fmt.Errorf("log length mismatch. Expected %d, got %d", len(tlog), len(logs))
@@ -53,7 +53,7 @@ func checkLogs(tlog []Log, logs state.Logs) error {
 					}
 				}
 			}
-			genBloom := common.LeftPadBytes(types.LogsBloom(state.Logs{logs[i]}).Bytes(), 256)
+			genBloom := common.LeftPadBytes(types.LogsBloom(vm.Logs{logs[i]}).Bytes(), 256)
 
 			if !bytes.Equal(genBloom, common.Hex2Bytes(log.BloomF)) {
 				return fmt.Errorf("bloom mismatch")
@@ -181,18 +181,18 @@ func (self *Env) BlockNumber() *big.Int  { return self.number }
 func (self *Env) Coinbase() common.Address { return self.coinbase }
 func (self *Env) Time() *big.Int           { return self.time }
 func (self *Env) Difficulty() *big.Int     { return self.difficulty }
-func (self *Env) State() *state.StateDB    { return self.state }
+func (self *Env) Db() vm.Database          { return self.state }
 func (self *Env) GasLimit() *big.Int       { return self.gasLimit }
 func (self *Env) VmType() vm.Type          { return vm.StdVmTy }
 func (self *Env) GetHash(n uint64) common.Hash {
 	return common.BytesToHash(crypto.Sha3([]byte(big.NewInt(int64(n)).String())))
 }
-func (self *Env) AddLog(log *state.Log) {
+func (self *Env) AddLog(log *vm.Log) {
 	self.state.AddLog(log)
 }
 func (self *Env) Depth() int     { return self.depth }
 func (self *Env) SetDepth(i int) { self.depth = i }
-func (self *Env) CanTransfer(from vm.Account, balance *big.Int) bool {
+func (self *Env) CanTransfer(from common.Address, balance *big.Int) bool {
 	if self.skipTransfer {
 		if self.initial {
 			self.initial = false
@@ -200,58 +200,53 @@ func (self *Env) CanTransfer(from vm.Account, balance *big.Int) bool {
 		}
 	}
 
-	return from.Balance().Cmp(balance) >= 0
+	return self.state.GetBalance(from).Cmp(balance) >= 0
+}
+func (self *Env) MakeSnapshot() vm.Database {
+	return self.state.Copy()
+}
+func (self *Env) SetSnapshot(copy vm.Database) {
+	self.state.Set(copy.(*state.StateDB))
 }
 
 func (self *Env) Transfer(from, to vm.Account, amount *big.Int) error {
 	if self.skipTransfer {
 		return nil
 	}
-	return vm.Transfer(from, to, amount)
-}
-
-func (self *Env) vm(addr *common.Address, data []byte, gas, price, value *big.Int) *core.Execution {
-	exec := core.NewExecution(self, addr, data, gas, price, value)
-
-	return exec
+	return core.Transfer(from, to, amount)
 }
 
-func (self *Env) Call(caller vm.ContextRef, addr common.Address, data []byte, gas, price, value *big.Int) ([]byte, error) {
+func (self *Env) Call(caller vm.ContractRef, addr common.Address, data []byte, gas, price, value *big.Int) ([]byte, error) {
 	if self.vmTest && self.depth > 0 {
 		caller.ReturnGas(gas, price)
 
 		return nil, nil
 	}
-	exe := self.vm(&addr, data, gas, price, value)
-	ret, err := exe.Call(addr, caller)
-	self.Gas = exe.Gas
+	ret, err := core.Call(self, caller, addr, data, gas, price, value)
+	self.Gas = gas
 
 	return ret, err
 
 }
-func (self *Env) CallCode(caller vm.ContextRef, addr common.Address, data []byte, gas, price, value *big.Int) ([]byte, error) {
+func (self *Env) CallCode(caller vm.ContractRef, addr common.Address, data []byte, gas, price, value *big.Int) ([]byte, error) {
 	if self.vmTest && self.depth > 0 {
 		caller.ReturnGas(gas, price)
 
 		return nil, nil
 	}
-
-	caddr := caller.Address()
-	exe := self.vm(&caddr, data, gas, price, value)
-	return exe.Call(addr, caller)
+	return core.CallCode(self, caller, addr, data, gas, price, value)
 }
 
-func (self *Env) Create(caller vm.ContextRef, data []byte, gas, price, value *big.Int) ([]byte, error, vm.ContextRef) {
-	exe := self.vm(nil, data, gas, price, value)
+func (self *Env) Create(caller vm.ContractRef, data []byte, gas, price, value *big.Int) ([]byte, common.Address, error) {
 	if self.vmTest {
 		caller.ReturnGas(gas, price)
 
 		nonce := self.state.GetNonce(caller.Address())
 		obj := self.state.GetOrNewStateObject(crypto.CreateAddress(caller.Address(), nonce))
 
-		return nil, nil, obj
+		return nil, obj.Address(), nil
 	} else {
-		return exe.Create(caller)
+		return core.Create(self, caller, data, gas, price, value)
 	}
 }
 
diff --git a/tests/vm_test.go b/tests/vm_test.go
index 96718db3c..34beb85e5 100644
--- a/tests/vm_test.go
+++ b/tests/vm_test.go
@@ -24,14 +24,14 @@ import (
 
 func BenchmarkVmAckermann32Tests(b *testing.B) {
 	fn := filepath.Join(vmTestDir, "vmPerformanceTest.json")
-	if err := BenchVmTest(fn, bconf{"ackermann32", true, os.Getenv("JITVM") == "true"}, b); err != nil {
+	if err := BenchVmTest(fn, bconf{"ackermann32", os.Getenv("JITFORCE") == "true", os.Getenv("JITVM") == "true"}, b); err != nil {
 		b.Error(err)
 	}
 }
 
 func BenchmarkVmFibonacci16Tests(b *testing.B) {
 	fn := filepath.Join(vmTestDir, "vmPerformanceTest.json")
-	if err := BenchVmTest(fn, bconf{"fibonacci16", true, os.Getenv("JITVM") == "true"}, b); err != nil {
+	if err := BenchVmTest(fn, bconf{"fibonacci16", os.Getenv("JITFORCE") == "true", os.Getenv("JITVM") == "true"}, b); err != nil {
 		b.Error(err)
 	}
 }
diff --git a/tests/vm_test_util.go b/tests/vm_test_util.go
index 71a4f5e33..b61995e31 100644
--- a/tests/vm_test_util.go
+++ b/tests/vm_test_util.go
@@ -185,7 +185,7 @@ func runVmTest(test VmTest) error {
 		ret  []byte
 		gas  *big.Int
 		err  error
-		logs state.Logs
+		logs vm.Logs
 	)
 
 	ret, logs, gas, err = RunVm(statedb, env, test.Exec)
@@ -234,7 +234,7 @@ func runVmTest(test VmTest) error {
 	return nil
 }
 
-func RunVm(state *state.StateDB, env, exec map[string]string) ([]byte, state.Logs, *big.Int, error) {
+func RunVm(state *state.StateDB, env, exec map[string]string) ([]byte, vm.Logs, *big.Int, error) {
 	var (
 		to    = common.HexToAddress(exec["address"])
 		from  = common.HexToAddress(exec["caller"])
diff --git a/xeth/xeth.go b/xeth/xeth.go
index 0494342a3..9d366d215 100644
--- a/xeth/xeth.go
+++ b/xeth/xeth.go
@@ -33,6 +33,7 @@ import (
 	"github.com/ethereum/go-ethereum/core"
 	"github.com/ethereum/go-ethereum/core/state"
 	"github.com/ethereum/go-ethereum/core/types"
+	"github.com/ethereum/go-ethereum/core/vm"
 	"github.com/ethereum/go-ethereum/crypto"
 	"github.com/ethereum/go-ethereum/eth"
 	"github.com/ethereum/go-ethereum/eth/filters"
@@ -541,7 +542,7 @@ func (self *XEth) NewLogFilter(earliest, latest int64, skip, max int, address []
 	filter.SetMax(max)
 	filter.SetAddress(cAddress(address))
 	filter.SetTopics(cTopics(topics))
-	filter.LogsCallback = func(logs state.Logs) {
+	filter.LogsCallback = func(logs vm.Logs) {
 		self.logMu.Lock()
 		defer self.logMu.Unlock()
 
@@ -580,7 +581,7 @@ func (self *XEth) NewBlockFilter() int {
 	id := self.filterManager.Add(filter)
 	self.blockQueue[id] = &hashQueue{timeout: time.Now()}
 
-	filter.BlockCallback = func(block *types.Block, logs state.Logs) {
+	filter.BlockCallback = func(block *types.Block, logs vm.Logs) {
 		self.blockMu.Lock()
 		defer self.blockMu.Unlock()
 
@@ -603,7 +604,7 @@ func (self *XEth) GetFilterType(id int) byte {
 	return UnknownFilterTy
 }
 
-func (self *XEth) LogFilterChanged(id int) state.Logs {
+func (self *XEth) LogFilterChanged(id int) vm.Logs {
 	self.logMu.Lock()
 	defer self.logMu.Unlock()
 
@@ -633,7 +634,7 @@ func (self *XEth) TransactionFilterChanged(id int) []common.Hash {
 	return nil
 }
 
-func (self *XEth) Logs(id int) state.Logs {
+func (self *XEth) Logs(id int) vm.Logs {
 	filter := self.filterManager.Get(id)
 	if filter != nil {
 		return filter.Find()
@@ -642,7 +643,7 @@ func (self *XEth) Logs(id int) state.Logs {
 	return nil
 }
 
-func (self *XEth) AllLogs(earliest, latest int64, skip, max int, address []string, topics [][]string) state.Logs {
+func (self *XEth) AllLogs(earliest, latest int64, skip, max int, address []string, topics [][]string) vm.Logs {
 	filter := filters.New(self.backend.ChainDb())
 	filter.SetEarliestBlock(earliest)
 	filter.SetLatestBlock(latest)
@@ -1029,19 +1030,19 @@ func (m callmsg) Data() []byte                  { return m.data }
 type logQueue struct {
 	mu sync.Mutex
 
-	logs    state.Logs
+	logs    vm.Logs
 	timeout time.Time
 	id      int
 }
 
-func (l *logQueue) add(logs ...*state.Log) {
+func (l *logQueue) add(logs ...*vm.Log) {
 	l.mu.Lock()
 	defer l.mu.Unlock()
 
 	l.logs = append(l.logs, logs...)
 }
 
-func (l *logQueue) get() state.Logs {
+func (l *logQueue) get() vm.Logs {
 	l.mu.Lock()
 	defer l.mu.Unlock()