Moved ethvm => vm

14 files changed, 2708 insertions, 0 deletions

diff --git a/vm/.ethtest b/vm/.ethtest
new file mode 100644
index 000000000..e69de29bb
--- /dev/null
+++ b/vm/.ethtest
diff --git a/vm/address.go b/vm/address.go
new file mode 100644
index 000000000..cfb7f36d9
--- /dev/null
+++ b/vm/address.go
@@ -0,0 +1,42 @@
+package vm
+
+import (
+	"math/big"
+
+	"github.com/ethereum/eth-go/ethcrypto"
+	"github.com/ethereum/eth-go/ethutil"
+)
+
+type Address interface {
+	Call(in []byte) []byte
+}
+
+type PrecompiledAddress struct {
+	Gas *big.Int
+	fn  func(in []byte) []byte
+}
+
+func (self PrecompiledAddress) Call(in []byte) []byte {
+	return self.fn(in)
+}
+
+var Precompiled = map[uint64]*PrecompiledAddress{
+	1: &PrecompiledAddress{big.NewInt(500), ecrecoverFunc},
+	2: &PrecompiledAddress{big.NewInt(100), sha256Func},
+	3: &PrecompiledAddress{big.NewInt(100), ripemd160Func},
+}
+
+func sha256Func(in []byte) []byte {
+	return ethcrypto.Sha256(in)
+}
+
+func ripemd160Func(in []byte) []byte {
+	return ethutil.RightPadBytes(ethcrypto.Ripemd160(in), 32)
+}
+
+func ecrecoverFunc(in []byte) []byte {
+	// In case of an invalid sig. Defaults to return nil
+	defer func() { recover() }()
+
+	return ethcrypto.Ecrecover(in)
+}
diff --git a/vm/asm.go b/vm/asm.go
new file mode 100644
index 000000000..d081e2b09
--- /dev/null
+++ b/vm/asm.go
@@ -0,0 +1,45 @@
+package vm
+
+import (
+	"fmt"
+	"math/big"
+
+	"github.com/ethereum/eth-go/ethutil"
+)
+
+func Disassemble(script []byte) (asm []string) {
+	pc := new(big.Int)
+	for {
+		if pc.Cmp(big.NewInt(int64(len(script)))) >= 0 {
+			return
+		}
+
+		// Get the memory location of pc
+		val := script[pc.Int64()]
+		// Get the opcode (it must be an opcode!)
+		op := OpCode(val)
+
+		asm = append(asm, fmt.Sprintf("%v", op))
+
+		switch op {
+		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:
+			pc.Add(pc, ethutil.Big1)
+			a := int64(op) - int64(PUSH1) + 1
+			if int(pc.Int64()+a) > len(script) {
+				return nil
+			}
+
+			data := script[pc.Int64() : pc.Int64()+a]
+			if len(data) == 0 {
+				data = []byte{0}
+			}
+			asm = append(asm, fmt.Sprintf("0x%x", data))
+
+			pc.Add(pc, big.NewInt(a-1))
+		}
+
+		pc.Add(pc, ethutil.Big1)
+	}
+
+	return
+}
diff --git a/vm/closure.go b/vm/closure.go
new file mode 100644
index 000000000..5a1e1d4d5
--- /dev/null
+++ b/vm/closure.go
@@ -0,0 +1,140 @@
+package vm
+
+// TODO Re write VM to use values instead of big integers?
+
+import (
+	"math/big"
+
+	"github.com/ethereum/eth-go/ethstate"
+	"github.com/ethereum/eth-go/ethutil"
+)
+
+type ClosureRef interface {
+	ReturnGas(*big.Int, *big.Int)
+	Address() []byte
+	Object() *ethstate.StateObject
+	GetStorage(*big.Int) *ethutil.Value
+	SetStorage(*big.Int, *ethutil.Value)
+}
+
+// Basic inline closure object which implement the 'closure' interface
+type Closure struct {
+	caller  ClosureRef
+	object  *ethstate.StateObject
+	Code    []byte
+	message *ethstate.Message
+	exe     *Execution
+
+	Gas, UsedGas, Price *big.Int
+
+	Args []byte
+}
+
+// Create a new closure for the given data items
+func NewClosure(msg *ethstate.Message, caller ClosureRef, object *ethstate.StateObject, code []byte, gas, price *big.Int) *Closure {
+	c := &Closure{message: msg, caller: caller, object: object, Code: code, Args: nil}
+
+	// Gas should be a pointer so it can safely be reduced through the run
+	// This pointer will be off the state transition
+	c.Gas = gas //new(big.Int).Set(gas)
+	// In most cases price and value are pointers to transaction objects
+	// and we don't want the transaction's values to change.
+	c.Price = new(big.Int).Set(price)
+	c.UsedGas = new(big.Int)
+
+	return c
+}
+
+// Retuns the x element in data slice
+func (c *Closure) GetStorage(x *big.Int) *ethutil.Value {
+	m := c.object.GetStorage(x)
+	if m == nil {
+		return ethutil.EmptyValue()
+	}
+
+	return m
+}
+
+func (c *Closure) Get(x *big.Int) *ethutil.Value {
+	return c.Gets(x, big.NewInt(1))
+}
+
+func (c *Closure) GetOp(x int) OpCode {
+	return OpCode(c.GetByte(x))
+}
+
+func (c *Closure) GetByte(x int) byte {
+	if x < len(c.Code) {
+		return c.Code[x]
+	}
+
+	return 0
+}
+
+func (c *Closure) GetBytes(x, y int) []byte {
+	if x >= len(c.Code) || y >= len(c.Code) {
+		return nil
+	}
+
+	return c.Code[x : x+y]
+}
+
+func (c *Closure) Gets(x, y *big.Int) *ethutil.Value {
+	if x.Int64() >= int64(len(c.Code)) || y.Int64() >= int64(len(c.Code)) {
+		return ethutil.NewValue(0)
+	}
+
+	partial := c.Code[x.Int64() : x.Int64()+y.Int64()]
+
+	return ethutil.NewValue(partial)
+}
+
+func (c *Closure) SetStorage(x *big.Int, val *ethutil.Value) {
+	c.object.SetStorage(x, val)
+}
+
+func (c *Closure) Address() []byte {
+	return c.object.Address()
+}
+
+func (c *Closure) Call(vm VirtualMachine, args []byte) ([]byte, *big.Int, error) {
+	c.Args = args
+
+	ret, err := vm.RunClosure(c)
+
+	return ret, c.UsedGas, err
+}
+
+func (c *Closure) Return(ret []byte) []byte {
+	// Return the remaining gas to the caller
+	c.caller.ReturnGas(c.Gas, c.Price)
+
+	return ret
+}
+
+func (c *Closure) UseGas(gas *big.Int) bool {
+	if c.Gas.Cmp(gas) < 0 {
+		return false
+	}
+
+	// Sub the amount of gas from the remaining
+	c.Gas.Sub(c.Gas, gas)
+	c.UsedGas.Add(c.UsedGas, gas)
+
+	return true
+}
+
+// Implement the caller interface
+func (c *Closure) ReturnGas(gas, price *big.Int) {
+	// Return the gas to the closure
+	c.Gas.Add(c.Gas, gas)
+	c.UsedGas.Sub(c.UsedGas, gas)
+}
+
+func (c *Closure) Object() *ethstate.StateObject {
+	return c.object
+}
+
+func (c *Closure) Caller() ClosureRef {
+	return c.caller
+}
diff --git a/vm/common.go b/vm/common.go
new file mode 100644
index 000000000..6921b38ff
--- /dev/null
+++ b/vm/common.go
@@ -0,0 +1,66 @@
+package vm
+
+import (
+	"math/big"
+
+	"github.com/ethereum/eth-go/ethlog"
+	"github.com/ethereum/eth-go/ethutil"
+)
+
+var vmlogger = ethlog.NewLogger("VM")
+
+type Type int
+
+const (
+	StandardVmTy Type = iota
+	DebugVmTy
+
+	MaxVmTy
+)
+
+var (
+	GasStep    = big.NewInt(1)
+	GasSha     = big.NewInt(20)
+	GasSLoad   = big.NewInt(20)
+	GasSStore  = big.NewInt(100)
+	GasBalance = big.NewInt(20)
+	GasCreate  = big.NewInt(100)
+	GasCall    = big.NewInt(20)
+	GasMemory  = big.NewInt(1)
+	GasData    = big.NewInt(5)
+	GasTx      = big.NewInt(500)
+
+	Pow256 = ethutil.BigPow(2, 256)
+
+	LogTyPretty byte = 0x1
+	LogTyDiff   byte = 0x2
+
+	U256 = ethutil.U256
+	S256 = ethutil.S256
+)
+
+const MaxCallDepth = 1024
+
+func calcMemSize(off, l *big.Int) *big.Int {
+	if l.Cmp(ethutil.Big0) == 0 {
+		return ethutil.Big0
+	}
+
+	return new(big.Int).Add(off, l)
+}
+
+// Simple helper
+func u256(n int64) *big.Int {
+	return big.NewInt(n)
+}
+
+// Mainly used for print variables and passing to Print*
+func toValue(val *big.Int) interface{} {
+	// Let's assume a string on right padded zero's
+	b := val.Bytes()
+	if b[0] != 0 && b[len(b)-1] == 0x0 && b[len(b)-2] == 0x0 {
+		return string(b)
+	}
+
+	return val
+}
diff --git a/vm/debugger.go b/vm/debugger.go
new file mode 100644
index 000000000..fdd5e34e2
--- /dev/null
+++ b/vm/debugger.go
@@ -0,0 +1,10 @@
+package vm
+
+import "github.com/ethereum/eth-go/ethstate"
+
+type Debugger interface {
+	BreakHook(step int, op OpCode, mem *Memory, stack *Stack, object *ethstate.StateObject) bool
+	StepHook(step int, op OpCode, mem *Memory, stack *Stack, object *ethstate.StateObject) bool
+	BreakPoints() []int64
+	SetCode(byteCode []byte)
+}
diff --git a/vm/environment.go b/vm/environment.go
new file mode 100644
index 000000000..2d933b65c
--- /dev/null
+++ b/vm/environment.go
@@ -0,0 +1,26 @@
+package vm
+
+import (
+	"math/big"
+
+	"github.com/ethereum/eth-go/ethstate"
+	"github.com/ethereum/eth-go/ethutil"
+)
+
+type Environment interface {
+	State() *ethstate.State
+
+	Origin() []byte
+	BlockNumber() *big.Int
+	PrevHash() []byte
+	Coinbase() []byte
+	Time() int64
+	Difficulty() *big.Int
+	BlockHash() []byte
+	GasLimit() *big.Int
+}
+
+type Object interface {
+	GetStorage(key *big.Int) *ethutil.Value
+	SetStorage(key *big.Int, value *ethutil.Value)
+}
diff --git a/vm/execution.go b/vm/execution.go
new file mode 100644
index 000000000..6bed43026
--- /dev/null
+++ b/vm/execution.go
@@ -0,0 +1,93 @@
+package vm
+
+import (
+	"fmt"
+	"math/big"
+
+	"github.com/ethereum/eth-go/ethstate"
+	"github.com/ethereum/eth-go/ethutil"
+)
+
+type Execution struct {
+	vm                VirtualMachine
+	address, input    []byte
+	Gas, price, value *big.Int
+	object            *ethstate.StateObject
+}
+
+func NewExecution(vm VirtualMachine, address, input []byte, gas, gasPrice, value *big.Int) *Execution {
+	return &Execution{vm: vm, address: address, input: input, Gas: gas, price: gasPrice, value: value}
+}
+
+func (self *Execution) Addr() []byte {
+	return self.address
+}
+
+func (self *Execution) Exec(codeAddr []byte, caller ClosureRef) ([]byte, error) {
+	// Retrieve the executing code
+	code := self.vm.Env().State().GetCode(codeAddr)
+
+	return self.exec(code, codeAddr, caller)
+}
+
+func (self *Execution) exec(code, caddr []byte, caller ClosureRef) (ret []byte, err error) {
+	env := self.vm.Env()
+
+	snapshot := env.State().Copy()
+	defer func() {
+		if err != nil {
+			env.State().Set(snapshot)
+		}
+	}()
+
+	msg := env.State().Manifest().AddMessage(&ethstate.Message{
+		To: self.address, From: caller.Address(),
+		Input:  self.input,
+		Origin: env.Origin(),
+		Block:  env.BlockHash(), Timestamp: env.Time(), Coinbase: env.Coinbase(), Number: env.BlockNumber(),
+		Value: self.value,
+	})
+
+	object := caller.Object()
+	if object.Balance.Cmp(self.value) < 0 {
+		caller.ReturnGas(self.Gas, self.price)
+
+		err = fmt.Errorf("Insufficient funds to transfer value. Req %v, has %v", self.value, object.Balance)
+	} else {
+		stateObject := env.State().GetOrNewStateObject(self.address)
+		self.object = stateObject
+
+		caller.Object().SubAmount(self.value)
+		stateObject.AddAmount(self.value)
+
+		// Pre-compiled contracts (address.go) 1, 2 & 3.
+		naddr := ethutil.BigD(caddr).Uint64()
+		if p := Precompiled[naddr]; p != nil {
+			if self.Gas.Cmp(p.Gas) >= 0 {
+				ret = p.Call(self.input)
+				self.vm.Printf("NATIVE_FUNC(%x) => %x", naddr, ret)
+			}
+		} else {
+			// Create a new callable closure
+			c := NewClosure(msg, caller, stateObject, code, self.Gas, self.price)
+			c.exe = self
+
+			if self.vm.Depth() == MaxCallDepth {
+				c.UseGas(c.Gas)
+
+				return c.Return(nil), fmt.Errorf("Max call depth exceeded (%d)", MaxCallDepth)
+			}
+
+			// Executer the closure and get the return value (if any)
+			ret, _, err = c.Call(self.vm, self.input)
+
+			msg.Output = ret
+		}
+	}
+
+	return
+}
+
+func (self *Execution) Create(caller ClosureRef) (ret []byte, err error) {
+	return self.exec(self.input, nil, caller)
+}
diff --git a/vm/stack.go b/vm/stack.go
new file mode 100644
index 000000000..55fdb6d15
--- /dev/null
+++ b/vm/stack.go
@@ -0,0 +1,162 @@
+package vm
+
+import (
+	"fmt"
+	"math"
+	"math/big"
+)
+
+type OpType int
+
+const (
+	tNorm = iota
+	tData
+	tExtro
+	tCrypto
+)
+
+type TxCallback func(opType OpType) bool
+
+// Simple push/pop stack mechanism
+type Stack struct {
+	data []*big.Int
+}
+
+func NewStack() *Stack {
+	return &Stack{}
+}
+
+func (st *Stack) Data() []*big.Int {
+	return st.data
+}
+
+func (st *Stack) Len() int {
+	return len(st.data)
+}
+
+func (st *Stack) Pop() *big.Int {
+	str := st.data[len(st.data)-1]
+
+	copy(st.data[:len(st.data)-1], st.data[:len(st.data)-1])
+	st.data = st.data[:len(st.data)-1]
+
+	return str
+}
+
+func (st *Stack) Popn() (*big.Int, *big.Int) {
+	ints := st.data[len(st.data)-2:]
+
+	copy(st.data[:len(st.data)-2], st.data[:len(st.data)-2])
+	st.data = st.data[:len(st.data)-2]
+
+	return ints[0], ints[1]
+}
+
+func (st *Stack) Peek() *big.Int {
+	str := st.data[len(st.data)-1]
+
+	return str
+}
+
+func (st *Stack) Peekn() (*big.Int, *big.Int) {
+	ints := st.data[len(st.data)-2:]
+
+	return ints[0], ints[1]
+}
+
+func (st *Stack) Swapn(n int) (*big.Int, *big.Int) {
+	st.data[len(st.data)-n], st.data[len(st.data)-1] = st.data[len(st.data)-1], st.data[len(st.data)-n]
+
+	return st.data[len(st.data)-n], st.data[len(st.data)-1]
+}
+
+func (st *Stack) Dupn(n int) *big.Int {
+	st.Push(st.data[len(st.data)-n])
+
+	return st.Peek()
+}
+
+func (st *Stack) Push(d *big.Int) {
+	st.data = append(st.data, new(big.Int).Set(d))
+}
+
+func (st *Stack) Get(amount *big.Int) []*big.Int {
+	// offset + size <= len(data)
+	length := big.NewInt(int64(len(st.data)))
+	if amount.Cmp(length) <= 0 {
+		start := new(big.Int).Sub(length, amount)
+		return st.data[start.Int64():length.Int64()]
+	}
+
+	return nil
+}
+
+func (st *Stack) Print() {
+	fmt.Println("### stack ###")
+	if len(st.data) > 0 {
+		for i, val := range st.data {
+			fmt.Printf("%-3d  %v\n", i, val)
+		}
+	} else {
+		fmt.Println("-- empty --")
+	}
+	fmt.Println("#############")
+}
+
+type Memory struct {
+	store []byte
+}
+
+func (m *Memory) Set(offset, size int64, value []byte) {
+	totSize := offset + size
+	lenSize := int64(len(m.store) - 1)
+	if totSize > lenSize {
+		// Calculate the diff between the sizes
+		diff := totSize - lenSize
+		if diff > 0 {
+			// Create a new empty slice and append it
+			newSlice := make([]byte, diff-1)
+			// Resize slice
+			m.store = append(m.store, newSlice...)
+		}
+	}
+	copy(m.store[offset:offset+size], value)
+}
+
+func (m *Memory) Resize(size uint64) {
+	if uint64(m.Len()) < size {
+		m.store = append(m.store, make([]byte, size-uint64(m.Len()))...)
+	}
+}
+
+func (m *Memory) Get(offset, size int64) []byte {
+	if len(m.store) > int(offset) {
+		end := int(math.Min(float64(len(m.store)), float64(offset+size)))
+
+		return m.store[offset:end]
+	}
+
+	return nil
+}
+
+func (m *Memory) Len() int {
+	return len(m.store)
+}
+
+func (m *Memory) Data() []byte {
+	return m.store
+}
+
+func (m *Memory) Print() {
+	fmt.Printf("### mem %d bytes ###\n", len(m.store))
+	if len(m.store) > 0 {
+		addr := 0
+		for i := 0; i+32 <= len(m.store); i += 32 {
+			fmt.Printf("%03d: % x\n", addr, m.store[i:i+32])
+			addr++
+		}
+	} else {
+		fmt.Println("-- empty --")
+	}
+	fmt.Println("####################")
+}
diff --git a/vm/types.go b/vm/types.go
new file mode 100644
index 000000000..5fd92052b
--- /dev/null
+++ b/vm/types.go
@@ -0,0 +1,314 @@
+package vm
+
+import (
+	"fmt"
+)
+
+type OpCode byte
+
+// Op codes
+const (
+	// 0x0 range - arithmetic ops
+	STOP = 0x00
+	ADD  = 0x01
+	MUL  = 0x02
+	SUB  = 0x03
+	DIV  = 0x04
+	SDIV = 0x05
+	MOD  = 0x06
+	SMOD = 0x07
+	EXP  = 0x08
+	NEG  = 0x09
+	LT   = 0x0a
+	GT   = 0x0b
+	SLT  = 0x0c
+	SGT  = 0x0d
+	EQ   = 0x0e
+	NOT  = 0x0f
+
+	// 0x10 range - bit ops
+	AND    = 0x10
+	OR     = 0x11
+	XOR    = 0x12
+	BYTE   = 0x13
+	ADDMOD = 0x14
+	MULMOD = 0x15
+
+	// 0x20 range - crypto
+	SHA3 = 0x20
+
+	// 0x30 range - closure state
+	ADDRESS      = 0x30
+	BALANCE      = 0x31
+	ORIGIN       = 0x32
+	CALLER       = 0x33
+	CALLVALUE    = 0x34
+	CALLDATALOAD = 0x35
+	CALLDATASIZE = 0x36
+	CALLDATACOPY = 0x37
+	CODESIZE     = 0x38
+	CODECOPY     = 0x39
+	GASPRICE     = 0x3a
+	EXTCODESIZE  = 0x3b
+	EXTCODECOPY  = 0x3c
+
+	// 0x40 range - block operations
+	PREVHASH   = 0x40
+	COINBASE   = 0x41
+	TIMESTAMP  = 0x42
+	NUMBER     = 0x43
+	DIFFICULTY = 0x44
+	GASLIMIT   = 0x45
+
+	// 0x50 range - 'storage' and execution
+	POP = 0x50
+	//DUP     = 0x51
+	//SWAP    = 0x52
+	MLOAD    = 0x53
+	MSTORE   = 0x54
+	MSTORE8  = 0x55
+	SLOAD    = 0x56
+	SSTORE   = 0x57
+	JUMP     = 0x58
+	JUMPI    = 0x59
+	PC       = 0x5a
+	MSIZE    = 0x5b
+	GAS      = 0x5c
+	JUMPDEST = 0x5d
+
+	// 0x60 range
+	PUSH1  = 0x60
+	PUSH2  = 0x61
+	PUSH3  = 0x62
+	PUSH4  = 0x63
+	PUSH5  = 0x64
+	PUSH6  = 0x65
+	PUSH7  = 0x66
+	PUSH8  = 0x67
+	PUSH9  = 0x68
+	PUSH10 = 0x69
+	PUSH11 = 0x6a
+	PUSH12 = 0x6b
+	PUSH13 = 0x6c
+	PUSH14 = 0x6d
+	PUSH15 = 0x6e
+	PUSH16 = 0x6f
+	PUSH17 = 0x70
+	PUSH18 = 0x71
+	PUSH19 = 0x72
+	PUSH20 = 0x73
+	PUSH21 = 0x74
+	PUSH22 = 0x75
+	PUSH23 = 0x76
+	PUSH24 = 0x77
+	PUSH25 = 0x78
+	PUSH26 = 0x79
+	PUSH27 = 0x7a
+	PUSH28 = 0x7b
+	PUSH29 = 0x7c
+	PUSH30 = 0x7d
+	PUSH31 = 0x7e
+	PUSH32 = 0x7f
+
+	DUP1  = 0x80
+	DUP2  = 0x81
+	DUP3  = 0x82
+	DUP4  = 0x83
+	DUP5  = 0x84
+	DUP6  = 0x85
+	DUP7  = 0x86
+	DUP8  = 0x87
+	DUP9  = 0x88
+	DUP10 = 0x89
+	DUP11 = 0x8a
+	DUP12 = 0x8b
+	DUP13 = 0x8c
+	DUP14 = 0x8d
+	DUP15 = 0x8e
+	DUP16 = 0x8f
+
+	SWAP1  = 0x90
+	SWAP2  = 0x91
+	SWAP3  = 0x92
+	SWAP4  = 0x93
+	SWAP5  = 0x94
+	SWAP6  = 0x95
+	SWAP7  = 0x96
+	SWAP8  = 0x97
+	SWAP9  = 0x98
+	SWAP10 = 0x99
+	SWAP11 = 0x9a
+	SWAP12 = 0x9b
+	SWAP13 = 0x9c
+	SWAP14 = 0x9d
+	SWAP15 = 0x9e
+	SWAP16 = 0x9f
+
+	// 0xf0 range - closures
+	CREATE   = 0xf0
+	CALL     = 0xf1
+	RETURN   = 0xf2
+	CALLCODE = 0xf3
+
+	// 0x70 range - other
+	LOG     = 0xfe // XXX Unofficial
+	SUICIDE = 0xff
+)
+
+// Since the opcodes aren't all in order we can't use a regular slice
+var opCodeToString = map[OpCode]string{
+	// 0x0 range - arithmetic ops
+	STOP: "STOP",
+	ADD:  "ADD",
+	MUL:  "MUL",
+	SUB:  "SUB",
+	DIV:  "DIV",
+	SDIV: "SDIV",
+	MOD:  "MOD",
+	SMOD: "SMOD",
+	EXP:  "EXP",
+	NEG:  "NEG",
+	LT:   "LT",
+	GT:   "GT",
+	SLT:  "SLT",
+	SGT:  "SGT",
+	EQ:   "EQ",
+	NOT:  "NOT",
+
+	// 0x10 range - bit ops
+	AND:    "AND",
+	OR:     "OR",
+	XOR:    "XOR",
+	BYTE:   "BYTE",
+	ADDMOD: "ADDMOD",
+	MULMOD: "MULMOD",
+
+	// 0x20 range - crypto
+	SHA3: "SHA3",
+
+	// 0x30 range - closure state
+	ADDRESS:      "ADDRESS",
+	BALANCE:      "BALANCE",
+	ORIGIN:       "ORIGIN",
+	CALLER:       "CALLER",
+	CALLVALUE:    "CALLVALUE",
+	CALLDATALOAD: "CALLDATALOAD",
+	CALLDATASIZE: "CALLDATASIZE",
+	CALLDATACOPY: "CALLDATACOPY",
+	CODESIZE:     "CODESIZE",
+	CODECOPY:     "CODECOPY",
+	GASPRICE:     "TXGASPRICE",
+
+	// 0x40 range - block operations
+	PREVHASH:    "PREVHASH",
+	COINBASE:    "COINBASE",
+	TIMESTAMP:   "TIMESTAMP",
+	NUMBER:      "NUMBER",
+	DIFFICULTY:  "DIFFICULTY",
+	GASLIMIT:    "GASLIMIT",
+	EXTCODESIZE: "EXTCODESIZE",
+	EXTCODECOPY: "EXTCODECOPY",
+
+	// 0x50 range - 'storage' and execution
+	POP: "POP",
+	//DUP:     "DUP",
+	//SWAP:    "SWAP",
+	MLOAD:    "MLOAD",
+	MSTORE:   "MSTORE",
+	MSTORE8:  "MSTORE8",
+	SLOAD:    "SLOAD",
+	SSTORE:   "SSTORE",
+	JUMP:     "JUMP",
+	JUMPI:    "JUMPI",
+	PC:       "PC",
+	MSIZE:    "MSIZE",
+	GAS:      "GAS",
+	JUMPDEST: "JUMPDEST",
+
+	// 0x60 range - push
+	PUSH1:  "PUSH1",
+	PUSH2:  "PUSH2",
+	PUSH3:  "PUSH3",
+	PUSH4:  "PUSH4",
+	PUSH5:  "PUSH5",
+	PUSH6:  "PUSH6",
+	PUSH7:  "PUSH7",
+	PUSH8:  "PUSH8",
+	PUSH9:  "PUSH9",
+	PUSH10: "PUSH10",
+	PUSH11: "PUSH11",
+	PUSH12: "PUSH12",
+	PUSH13: "PUSH13",
+	PUSH14: "PUSH14",
+	PUSH15: "PUSH15",
+	PUSH16: "PUSH16",
+	PUSH17: "PUSH17",
+	PUSH18: "PUSH18",
+	PUSH19: "PUSH19",
+	PUSH20: "PUSH20",
+	PUSH21: "PUSH21",
+	PUSH22: "PUSH22",
+	PUSH23: "PUSH23",
+	PUSH24: "PUSH24",
+	PUSH25: "PUSH25",
+	PUSH26: "PUSH26",
+	PUSH27: "PUSH27",
+	PUSH28: "PUSH28",
+	PUSH29: "PUSH29",
+	PUSH30: "PUSH30",
+	PUSH31: "PUSH31",
+	PUSH32: "PUSH32",
+
+	DUP1:  "DUP1",
+	DUP2:  "DUP2",
+	DUP3:  "DUP3",
+	DUP4:  "DUP4",
+	DUP5:  "DUP5",
+	DUP6:  "DUP6",
+	DUP7:  "DUP7",
+	DUP8:  "DUP8",
+	DUP9:  "DUP9",
+	DUP10: "DUP10",
+	DUP11: "DUP11",
+	DUP12: "DUP12",
+	DUP13: "DUP13",
+	DUP14: "DUP14",
+	DUP15: "DUP15",
+	DUP16: "DUP16",
+
+	SWAP1:  "SWAP1",
+	SWAP2:  "SWAP2",
+	SWAP3:  "SWAP3",
+	SWAP4:  "SWAP4",
+	SWAP5:  "SWAP5",
+	SWAP6:  "SWAP6",
+	SWAP7:  "SWAP7",
+	SWAP8:  "SWAP8",
+	SWAP9:  "SWAP9",
+	SWAP10: "SWAP10",
+	SWAP11: "SWAP11",
+	SWAP12: "SWAP12",
+	SWAP13: "SWAP13",
+	SWAP14: "SWAP14",
+	SWAP15: "SWAP15",
+	SWAP16: "SWAP16",
+
+	// 0xf0 range
+	CREATE:   "CREATE",
+	CALL:     "CALL",
+	RETURN:   "RETURN",
+	CALLCODE: "CALLCODE",
+
+	// 0x70 range - other
+	LOG:     "LOG",
+	SUICIDE: "SUICIDE",
+}
+
+func (o OpCode) String() string {
+	str := opCodeToString[o]
+	if len(str) == 0 {
+		return fmt.Sprintf("Missing opcode 0x%x", int(o))
+	}
+
+	return str
+}
diff --git a/vm/virtual_machine.go b/vm/virtual_machine.go
new file mode 100644
index 000000000..cc8cd39a9
--- /dev/null
+++ b/vm/virtual_machine.go
@@ -0,0 +1,9 @@
+package vm
+
+type VirtualMachine interface {
+	Env() Environment
+	RunClosure(*Closure) ([]byte, error)
+	Depth() int
+	Printf(string, ...interface{}) VirtualMachine
+	Endl() VirtualMachine
+}
diff --git a/vm/vm.go b/vm/vm.go
new file mode 100644
index 000000000..72d4f7131
--- /dev/null
+++ b/vm/vm.go
@@ -0,0 +1,724 @@
+package vm
+
+import (
+	"fmt"
+	"math/big"
+
+	"github.com/ethereum/eth-go/ethcrypto"
+	"github.com/ethereum/eth-go/ethutil"
+)
+
+// BIG FAT WARNING. THIS VM IS NOT YET IS USE!
+// I want to get all VM tests pass first before updating this VM
+
+type Vm struct {
+	env   Environment
+	err   error
+	depth int
+}
+
+func New(env Environment, typ Type) VirtualMachine {
+	switch typ {
+	case DebugVmTy:
+		return NewDebugVm(env)
+	default:
+		return &Vm{env: env}
+	}
+}
+
+func (self *Vm) RunClosure(closure *Closure) (ret []byte, err error) {
+	self.depth++
+
+	// Recover from any require exception
+	defer func() {
+		if r := recover(); r != nil {
+			ret = closure.Return(nil)
+			err = fmt.Errorf("%v", r)
+		}
+	}()
+
+	// Don't bother with the execution if there's no code.
+	if len(closure.Code) == 0 {
+		return closure.Return(nil), nil
+	}
+
+	var (
+		op OpCode
+
+		mem     = &Memory{}
+		stack   = NewStack()
+		pc      = 0
+		step    = 0
+		require = func(m int) {
+			if stack.Len() < m {
+				panic(fmt.Sprintf("%04v (%v) stack err size = %d, required = %d", pc, op, stack.Len(), m))
+			}
+		}
+	)
+
+	for {
+		// The base for all big integer arithmetic
+		base := new(big.Int)
+
+		step++
+		// Get the memory location of pc
+		op := closure.GetOp(pc)
+
+		gas := new(big.Int)
+		addStepGasUsage := func(amount *big.Int) {
+			gas.Add(gas, amount)
+		}
+
+		addStepGasUsage(GasStep)
+
+		var newMemSize *big.Int = ethutil.Big0
+		switch op {
+		case STOP:
+			gas.Set(ethutil.Big0)
+		case SUICIDE:
+			gas.Set(ethutil.Big0)
+		case SLOAD:
+			gas.Set(GasSLoad)
+		case SSTORE:
+			var mult *big.Int
+			y, x := stack.Peekn()
+			val := closure.GetStorage(x)
+			if val.BigInt().Cmp(ethutil.Big0) == 0 && len(y.Bytes()) > 0 {
+				mult = ethutil.Big2
+			} else if val.BigInt().Cmp(ethutil.Big0) != 0 && len(y.Bytes()) == 0 {
+				mult = ethutil.Big0
+			} else {
+				mult = ethutil.Big1
+			}
+			gas = new(big.Int).Mul(mult, GasSStore)
+		case BALANCE:
+			gas.Set(GasBalance)
+		case MSTORE:
+			require(2)
+			newMemSize = calcMemSize(stack.Peek(), u256(32))
+		case MLOAD:
+			require(1)
+
+			newMemSize = calcMemSize(stack.Peek(), u256(32))
+		case MSTORE8:
+			require(2)
+			newMemSize = calcMemSize(stack.Peek(), u256(1))
+		case RETURN:
+			require(2)
+
+			newMemSize = calcMemSize(stack.Peek(), stack.data[stack.Len()-2])
+		case SHA3:
+			require(2)
+
+			gas.Set(GasSha)
+
+			newMemSize = calcMemSize(stack.Peek(), stack.data[stack.Len()-2])
+		case CALLDATACOPY:
+			require(2)
+
+			newMemSize = calcMemSize(stack.Peek(), stack.data[stack.Len()-3])
+		case CODECOPY:
+			require(3)
+
+			newMemSize = calcMemSize(stack.Peek(), stack.data[stack.Len()-3])
+		case EXTCODECOPY:
+			require(4)
+
+			newMemSize = calcMemSize(stack.data[stack.Len()-2], stack.data[stack.Len()-4])
+		case CALL, CALLCODE:
+			require(7)
+			gas.Set(GasCall)
+			addStepGasUsage(stack.data[stack.Len()-1])
+
+			x := calcMemSize(stack.data[stack.Len()-6], stack.data[stack.Len()-7])
+			y := calcMemSize(stack.data[stack.Len()-4], stack.data[stack.Len()-5])
+
+			newMemSize = ethutil.BigMax(x, y)
+		case CREATE:
+			require(3)
+			gas.Set(GasCreate)
+
+			newMemSize = calcMemSize(stack.data[stack.Len()-2], stack.data[stack.Len()-3])
+		}
+
+		if newMemSize.Cmp(ethutil.Big0) > 0 {
+			newMemSize.Add(newMemSize, u256(31))
+			newMemSize.Div(newMemSize, u256(32))
+			newMemSize.Mul(newMemSize, u256(32))
+
+			if newMemSize.Cmp(u256(int64(mem.Len()))) > 0 {
+				memGasUsage := new(big.Int).Sub(newMemSize, u256(int64(mem.Len())))
+				memGasUsage.Mul(GasMemory, memGasUsage)
+				memGasUsage.Div(memGasUsage, u256(32))
+
+				addStepGasUsage(memGasUsage)
+			}
+		}
+
+		if !closure.UseGas(gas) {
+			err := fmt.Errorf("Insufficient gas for %v. req %v has %v", op, gas, closure.Gas)
+
+			closure.UseGas(closure.Gas)
+
+			return closure.Return(nil), err
+		}
+
+		mem.Resize(newMemSize.Uint64())
+
+		switch op {
+		// 0x20 range
+		case ADD:
+			require(2)
+			x, y := stack.Popn()
+
+			base.Add(y, x)
+
+			U256(base)
+
+			// Pop result back on the stack
+			stack.Push(base)
+		case SUB:
+			require(2)
+			x, y := stack.Popn()
+
+			base.Sub(y, x)
+
+			U256(base)
+
+			// Pop result back on the stack
+			stack.Push(base)
+		case MUL:
+			require(2)
+			x, y := stack.Popn()
+
+			base.Mul(y, x)
+
+			U256(base)
+
+			// Pop result back on the stack
+			stack.Push(base)
+		case DIV:
+			require(2)
+			x, y := stack.Popn()
+
+			if x.Cmp(ethutil.Big0) != 0 {
+				base.Div(y, x)
+			}
+
+			U256(base)
+
+			// Pop result back on the stack
+			stack.Push(base)
+		case SDIV:
+			require(2)
+			y, x := S256(stack.Pop()), S256(stack.Pop())
+
+			if x.Cmp(ethutil.Big0) == 0 {
+				base.Set(ethutil.Big0)
+			} else {
+				n := new(big.Int)
+				if new(big.Int).Mul(y, x).Cmp(ethutil.Big0) < 0 {
+					n.SetInt64(-1)
+				} else {
+					n.SetInt64(1)
+				}
+
+				base.Div(y.Abs(y), x.Mul(x.Abs(x), n))
+
+				U256(base)
+			}
+
+			stack.Push(base)
+		case MOD:
+			require(2)
+			x, y := stack.Popn()
+
+			base.Mod(y, x)
+
+			U256(base)
+
+			stack.Push(base)
+		case SMOD:
+			require(2)
+			y, x := S256(stack.Pop()), S256(stack.Pop())
+
+			if x.Cmp(ethutil.Big0) == 0 {
+				base.Set(ethutil.Big0)
+			} else {
+				n := new(big.Int)
+				if y.Cmp(ethutil.Big0) < 0 {
+					n.SetInt64(-1)
+				} else {
+					n.SetInt64(1)
+				}
+
+				base.Mod(y.Abs(y), x.Mul(x.Abs(x), n))
+
+				U256(base)
+			}
+
+			stack.Push(base)
+
+		case EXP:
+			require(2)
+			x, y := stack.Popn()
+
+			base.Exp(y, x, Pow256)
+
+			U256(base)
+
+			stack.Push(base)
+		case NEG:
+			require(1)
+			base.Sub(Pow256, stack.Pop())
+
+			base = U256(base)
+
+			stack.Push(base)
+		case LT:
+			require(2)
+			x, y := stack.Popn()
+			// x < y
+			if y.Cmp(x) < 0 {
+				stack.Push(ethutil.BigTrue)
+			} else {
+				stack.Push(ethutil.BigFalse)
+			}
+		case GT:
+			require(2)
+			x, y := stack.Popn()
+
+			// x > y
+			if y.Cmp(x) > 0 {
+				stack.Push(ethutil.BigTrue)
+			} else {
+				stack.Push(ethutil.BigFalse)
+			}
+
+		case SLT:
+			require(2)
+			y, x := S256(stack.Pop()), S256(stack.Pop())
+			// x < y
+			if y.Cmp(S256(x)) < 0 {
+				stack.Push(ethutil.BigTrue)
+			} else {
+				stack.Push(ethutil.BigFalse)
+			}
+		case SGT:
+			require(2)
+			y, x := S256(stack.Pop()), S256(stack.Pop())
+
+			// x > y
+			if y.Cmp(x) > 0 {
+				stack.Push(ethutil.BigTrue)
+			} else {
+				stack.Push(ethutil.BigFalse)
+			}
+
+		case EQ:
+			require(2)
+			x, y := stack.Popn()
+
+			// x == y
+			if x.Cmp(y) == 0 {
+				stack.Push(ethutil.BigTrue)
+			} else {
+				stack.Push(ethutil.BigFalse)
+			}
+		case NOT:
+			require(1)
+			x := stack.Pop()
+			if x.Cmp(ethutil.BigFalse) > 0 {
+				stack.Push(ethutil.BigFalse)
+			} else {
+				stack.Push(ethutil.BigTrue)
+			}
+
+			// 0x10 range
+		case AND:
+			require(2)
+			x, y := stack.Popn()
+
+			stack.Push(base.And(y, x))
+		case OR:
+			require(2)
+			x, y := stack.Popn()
+
+			stack.Push(base.Or(y, x))
+		case XOR:
+			require(2)
+			x, y := stack.Popn()
+
+			stack.Push(base.Xor(y, x))
+		case BYTE:
+			require(2)
+			val, th := stack.Popn()
+			if th.Cmp(big.NewInt(32)) < 0 && th.Cmp(big.NewInt(int64(len(val.Bytes())))) < 0 {
+				byt := big.NewInt(int64(ethutil.LeftPadBytes(val.Bytes(), 32)[th.Int64()]))
+				stack.Push(byt)
+
+			} else {
+				stack.Push(ethutil.BigFalse)
+			}
+		case ADDMOD:
+			require(3)
+
+			x := stack.Pop()
+			y := stack.Pop()
+			z := stack.Pop()
+
+			base.Add(x, y)
+			base.Mod(base, z)
+
+			U256(base)
+
+			stack.Push(base)
+		case MULMOD:
+			require(3)
+
+			x := stack.Pop()
+			y := stack.Pop()
+			z := stack.Pop()
+
+			base.Mul(x, y)
+			base.Mod(base, z)
+
+			U256(base)
+
+			stack.Push(base)
+
+			// 0x20 range
+		case SHA3:
+			require(2)
+			size, offset := stack.Popn()
+			data := ethcrypto.Sha3(mem.Get(offset.Int64(), size.Int64()))
+
+			stack.Push(ethutil.BigD(data))
+
+			// 0x30 range
+		case ADDRESS:
+			stack.Push(ethutil.BigD(closure.Address()))
+
+		case BALANCE:
+			require(1)
+
+			addr := stack.Pop().Bytes()
+			balance := self.env.State().GetBalance(addr)
+
+			stack.Push(balance)
+
+		case ORIGIN:
+			origin := self.env.Origin()
+
+			stack.Push(ethutil.BigD(origin))
+
+		case CALLER:
+			caller := closure.caller.Address()
+			stack.Push(ethutil.BigD(caller))
+
+		case CALLVALUE:
+			value := closure.exe.value
+
+			stack.Push(value)
+
+		case CALLDATALOAD:
+			require(1)
+			var (
+				offset  = stack.Pop()
+				data    = make([]byte, 32)
+				lenData = big.NewInt(int64(len(closure.Args)))
+			)
+
+			if lenData.Cmp(offset) >= 0 {
+				length := new(big.Int).Add(offset, ethutil.Big32)
+				length = ethutil.BigMin(length, lenData)
+
+				copy(data, closure.Args[offset.Int64():length.Int64()])
+			}
+
+			stack.Push(ethutil.BigD(data))
+		case CALLDATASIZE:
+			l := int64(len(closure.Args))
+			stack.Push(big.NewInt(l))
+
+		case CALLDATACOPY:
+			var (
+				size = int64(len(closure.Args))
+				mOff = stack.Pop().Int64()
+				cOff = stack.Pop().Int64()
+				l    = stack.Pop().Int64()
+			)
+
+			if cOff > size {
+				cOff = 0
+				l = 0
+			} else if cOff+l > size {
+				l = 0
+			}
+
+			code := closure.Args[cOff : cOff+l]
+
+			mem.Set(mOff, l, code)
+		case CODESIZE, EXTCODESIZE:
+			var code []byte
+			if op == EXTCODECOPY {
+				addr := stack.Pop().Bytes()
+
+				code = self.env.State().GetCode(addr)
+			} else {
+				code = closure.Code
+			}
+
+			l := big.NewInt(int64(len(code)))
+			stack.Push(l)
+
+		case CODECOPY, EXTCODECOPY:
+			var code []byte
+			if op == EXTCODECOPY {
+				addr := stack.Pop().Bytes()
+
+				code = self.env.State().GetCode(addr)
+			} else {
+				code = closure.Code
+			}
+
+			var (
+				size = int64(len(code))
+				mOff = stack.Pop().Int64()
+				cOff = stack.Pop().Int64()
+				l    = stack.Pop().Int64()
+			)
+
+			if cOff > size {
+				cOff = 0
+				l = 0
+			} else if cOff+l > size {
+				l = 0
+			}
+
+			codeCopy := code[cOff : cOff+l]
+
+			mem.Set(mOff, l, codeCopy)
+		case GASPRICE:
+			stack.Push(closure.Price)
+
+			// 0x40 range
+		case PREVHASH:
+			prevHash := self.env.PrevHash()
+
+			stack.Push(ethutil.BigD(prevHash))
+
+		case COINBASE:
+			coinbase := self.env.Coinbase()
+
+			stack.Push(ethutil.BigD(coinbase))
+
+		case TIMESTAMP:
+			time := self.env.Time()
+
+			stack.Push(big.NewInt(time))
+
+		case NUMBER:
+			number := self.env.BlockNumber()
+
+			stack.Push(number)
+
+		case DIFFICULTY:
+			difficulty := self.env.Difficulty()
+
+			stack.Push(difficulty)
+
+		case GASLIMIT:
+			// TODO
+			stack.Push(big.NewInt(0))
+
+			// 0x50 range
+		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:
+			a := int(op - PUSH1 + 1)
+			val := ethutil.BigD(closure.GetBytes(int(pc+1), a))
+			// Push value to stack
+			stack.Push(val)
+
+			pc += a
+
+			step += int(op) - int(PUSH1) + 1
+		case POP:
+			require(1)
+			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.Dupn(n)
+		case SWAP1, SWAP2, SWAP3, SWAP4, SWAP5, SWAP6, SWAP7, SWAP8, SWAP9, SWAP10, SWAP11, SWAP12, SWAP13, SWAP14, SWAP15, SWAP16:
+			n := int(op - SWAP1 + 2)
+			stack.Swapn(n)
+
+		case MLOAD:
+			require(1)
+			offset := stack.Pop()
+			val := ethutil.BigD(mem.Get(offset.Int64(), 32))
+			stack.Push(val)
+
+		case MSTORE: // Store the value at stack top-1 in to memory at location stack top
+			require(2)
+			// Pop value of the stack
+			val, mStart := stack.Popn()
+			mem.Set(mStart.Int64(), 32, ethutil.BigToBytes(val, 256))
+
+		case MSTORE8:
+			require(2)
+			off := stack.Pop()
+			val := stack.Pop()
+
+			mem.store[off.Int64()] = byte(val.Int64() & 0xff)
+
+		case SLOAD:
+			require(1)
+			loc := stack.Pop()
+			val := closure.GetStorage(loc)
+
+			stack.Push(val.BigInt())
+
+		case SSTORE:
+			require(2)
+			val, loc := stack.Popn()
+			closure.SetStorage(loc, ethutil.NewValue(val))
+
+			closure.message.AddStorageChange(loc.Bytes())
+
+		case JUMP:
+			require(1)
+			pc = int(stack.Pop().Int64())
+			// Reduce pc by one because of the increment that's at the end of this for loop
+
+			continue
+		case JUMPI:
+			require(2)
+			cond, pos := stack.Popn()
+			if cond.Cmp(ethutil.BigTrue) >= 0 {
+				pc = int(pos.Int64())
+
+				if closure.GetOp(int(pc)) != JUMPDEST {
+					return closure.Return(nil), fmt.Errorf("JUMP missed JUMPDEST %v", pc)
+				}
+
+				continue
+			}
+		case JUMPDEST:
+		case PC:
+			stack.Push(u256(int64(pc)))
+		case MSIZE:
+			stack.Push(big.NewInt(int64(mem.Len())))
+		case GAS:
+			stack.Push(closure.Gas)
+			// 0x60 range
+		case CREATE:
+			require(3)
+
+			var (
+				err          error
+				value        = stack.Pop()
+				size, offset = stack.Popn()
+				input        = mem.Get(offset.Int64(), size.Int64())
+				gas          = new(big.Int).Set(closure.Gas)
+
+				// Snapshot the current stack so we are able to
+				// revert back to it later.
+				//snapshot = self.env.State().Copy()
+			)
+
+			// Generate a new address
+			addr := ethcrypto.CreateAddress(closure.Address(), closure.object.Nonce)
+			closure.object.Nonce++
+
+			closure.UseGas(closure.Gas)
+
+			msg := NewExecution(self, addr, input, gas, closure.Price, value)
+			ret, err := msg.Exec(addr, closure)
+			if err != nil {
+				stack.Push(ethutil.BigFalse)
+
+				// Revert the state as it was before.
+				//self.env.State().Set(snapshot)
+
+			} else {
+				msg.object.Code = ret
+
+				stack.Push(ethutil.BigD(addr))
+			}
+
+		case CALL, CALLCODE:
+			require(7)
+
+			gas := stack.Pop()
+			// Pop gas and value of the stack.
+			value, addr := stack.Popn()
+			// Pop input size and offset
+			inSize, inOffset := stack.Popn()
+			// Pop return size and offset
+			retSize, retOffset := stack.Popn()
+
+			// Get the arguments from the memory
+			args := mem.Get(inOffset.Int64(), inSize.Int64())
+
+			//snapshot := self.env.State().Copy()
+
+			var executeAddr []byte
+			if op == CALLCODE {
+				executeAddr = closure.Address()
+			} else {
+				executeAddr = addr.Bytes()
+			}
+
+			msg := NewExecution(self, executeAddr, args, gas, closure.Price, value)
+			ret, err := msg.Exec(addr.Bytes(), closure)
+			if err != nil {
+				stack.Push(ethutil.BigFalse)
+
+				//self.env.State().Set(snapshot)
+			} else {
+				stack.Push(ethutil.BigTrue)
+
+				mem.Set(retOffset.Int64(), retSize.Int64(), ret)
+			}
+
+		case RETURN:
+			require(2)
+			size, offset := stack.Popn()
+			ret := mem.Get(offset.Int64(), size.Int64())
+
+			return closure.Return(ret), nil
+		case SUICIDE:
+			require(1)
+
+			receiver := self.env.State().GetOrNewStateObject(stack.Pop().Bytes())
+
+			receiver.AddAmount(closure.object.Balance)
+
+			closure.object.MarkForDeletion()
+
+			fallthrough
+		case STOP: // Stop the closure
+
+			return closure.Return(nil), nil
+		default:
+			vmlogger.Debugf("(pc) %-3v Invalid opcode %x\n", pc, op)
+
+			//panic(fmt.Sprintf("Invalid opcode %x", op))
+
+			return closure.Return(nil), fmt.Errorf("Invalid opcode %x", op)
+		}
+
+		pc++
+	}
+}
+
+func (self *Vm) Env() Environment {
+	return self.env
+}
+
+func (self *Vm) Depth() int {
+	return self.depth
+}
+
+func (self *Vm) Printf(format string, v ...interface{}) VirtualMachine { return self }
+func (self *Vm) Endl() VirtualMachine                                  { return self }
diff --git a/vm/vm_debug.go b/vm/vm_debug.go
new file mode 100644
index 000000000..785e699c7
--- /dev/null
+++ b/vm/vm_debug.go
@@ -0,0 +1,922 @@
+package vm
+
+import (
+	"fmt"
+	"math/big"
+
+	"github.com/ethereum/eth-go/ethcrypto"
+	"github.com/ethereum/eth-go/ethutil"
+)
+
+type DebugVm struct {
+	env Environment
+
+	logTy  byte
+	logStr string
+
+	err error
+
+	// Debugging
+	Dbg Debugger
+
+	BreakPoints []int64
+	Stepping    bool
+	Fn          string
+
+	Recoverable bool
+
+	depth int
+}
+
+func NewDebugVm(env Environment) *DebugVm {
+	lt := LogTyPretty
+	if ethutil.Config.Diff {
+		lt = LogTyDiff
+	}
+
+	return &DebugVm{env: env, logTy: lt, Recoverable: true}
+}
+
+func (self *DebugVm) RunClosure(closure *Closure) (ret []byte, err error) {
+	self.depth++
+
+	var (
+		op OpCode
+
+		mem      = &Memory{}
+		stack    = NewStack()
+		pc       = big.NewInt(0)
+		step     = 0
+		prevStep = 0
+		state    = self.env.State()
+		require  = func(m int) {
+			if stack.Len() < m {
+				panic(fmt.Sprintf("%04v (%v) stack err size = %d, required = %d", pc, op, stack.Len(), m))
+			}
+		}
+
+		jump = func(pos *big.Int) {
+			p := int(pos.Int64())
+
+			self.Printf(" ~> %v", pos)
+			// Return to start
+			if p == 0 {
+				pc = big.NewInt(0)
+			} else {
+				nop := OpCode(closure.GetOp(p - 1))
+				if nop != JUMPDEST {
+					panic(fmt.Sprintf("JUMP missed JUMPDEST (%v) %v", nop, p))
+				}
+
+				pc = pos
+			}
+
+			self.Endl()
+		}
+	)
+
+	if self.Recoverable {
+		// Recover from any require exception
+		defer func() {
+			if r := recover(); r != nil {
+				self.Endl()
+
+				ret = closure.Return(nil)
+				err = fmt.Errorf("%v", r)
+			}
+		}()
+	}
+
+	// Debug hook
+	if self.Dbg != nil {
+		self.Dbg.SetCode(closure.Code)
+	}
+
+	// Don't bother with the execution if there's no code.
+	if len(closure.Code) == 0 {
+		return closure.Return(nil), nil
+	}
+
+	vmlogger.Debugf("(%s) %x gas: %v (d) %x\n", self.Fn, closure.Address(), closure.Gas, closure.Args)
+
+	for {
+		prevStep = step
+		// The base for all big integer arithmetic
+		base := new(big.Int)
+
+		step++
+		// Get the memory location of pc
+		op := OpCode(closure.Get(pc).Uint())
+
+		// XXX Leave this Println intact. Don't change this to the log system.
+		// Used for creating diffs between implementations
+		if self.logTy == LogTyDiff {
+			switch op {
+			case STOP, RETURN, SUICIDE:
+				state.GetStateObject(closure.Address()).EachStorage(func(key string, value *ethutil.Value) {
+					value.Decode()
+					fmt.Printf("%x %x\n", new(big.Int).SetBytes([]byte(key)).Bytes(), value.Bytes())
+				})
+			}
+
+			b := pc.Bytes()
+			if len(b) == 0 {
+				b = []byte{0}
+			}
+
+			fmt.Printf("%x %x %x %x\n", closure.Address(), b, []byte{byte(op)}, closure.Gas.Bytes())
+		}
+
+		gas := new(big.Int)
+		addStepGasUsage := func(amount *big.Int) {
+			if amount.Cmp(ethutil.Big0) >= 0 {
+				gas.Add(gas, amount)
+			}
+		}
+
+		addStepGasUsage(GasStep)
+
+		var newMemSize *big.Int = ethutil.Big0
+		switch op {
+		case STOP:
+			gas.Set(ethutil.Big0)
+		case SUICIDE:
+			gas.Set(ethutil.Big0)
+		case SLOAD:
+			gas.Set(GasSLoad)
+		case SSTORE:
+			var mult *big.Int
+			y, x := stack.Peekn()
+			val := closure.GetStorage(x)
+			if val.BigInt().Cmp(ethutil.Big0) == 0 && len(y.Bytes()) > 0 {
+				mult = ethutil.Big2
+			} else if val.BigInt().Cmp(ethutil.Big0) != 0 && len(y.Bytes()) == 0 {
+				mult = ethutil.Big0
+			} else {
+				mult = ethutil.Big1
+			}
+			gas = new(big.Int).Mul(mult, GasSStore)
+		case BALANCE:
+			gas.Set(GasBalance)
+		case MSTORE:
+			require(2)
+			newMemSize = calcMemSize(stack.Peek(), u256(32))
+		case MLOAD:
+			require(1)
+
+			newMemSize = calcMemSize(stack.Peek(), u256(32))
+		case MSTORE8:
+			require(2)
+			newMemSize = calcMemSize(stack.Peek(), u256(1))
+		case RETURN:
+			require(2)
+
+			newMemSize = calcMemSize(stack.Peek(), stack.data[stack.Len()-2])
+		case SHA3:
+			require(2)
+
+			gas.Set(GasSha)
+
+			newMemSize = calcMemSize(stack.Peek(), stack.data[stack.Len()-2])
+		case CALLDATACOPY:
+			require(2)
+
+			newMemSize = calcMemSize(stack.Peek(), stack.data[stack.Len()-3])
+		case CODECOPY:
+			require(3)
+
+			newMemSize = calcMemSize(stack.Peek(), stack.data[stack.Len()-3])
+		case EXTCODECOPY:
+			require(4)
+
+			newMemSize = calcMemSize(stack.data[stack.Len()-2], stack.data[stack.Len()-4])
+		case CALL, CALLCODE:
+			require(7)
+			gas.Set(GasCall)
+			addStepGasUsage(stack.data[stack.Len()-1])
+
+			x := calcMemSize(stack.data[stack.Len()-6], stack.data[stack.Len()-7])
+			y := calcMemSize(stack.data[stack.Len()-4], stack.data[stack.Len()-5])
+
+			newMemSize = ethutil.BigMax(x, y)
+		case CREATE:
+			require(3)
+			gas.Set(GasCreate)
+
+			newMemSize = calcMemSize(stack.data[stack.Len()-2], stack.data[stack.Len()-3])
+		}
+
+		if newMemSize.Cmp(ethutil.Big0) > 0 {
+			newMemSize.Add(newMemSize, u256(31))
+			newMemSize.Div(newMemSize, u256(32))
+			newMemSize.Mul(newMemSize, u256(32))
+
+			if newMemSize.Cmp(u256(int64(mem.Len()))) > 0 {
+				memGasUsage := new(big.Int).Sub(newMemSize, u256(int64(mem.Len())))
+				memGasUsage.Mul(GasMemory, memGasUsage)
+				memGasUsage.Div(memGasUsage, u256(32))
+
+				addStepGasUsage(memGasUsage)
+			}
+		}
+
+		self.Printf("(pc) %-3d -o- %-14s", pc, op.String())
+		self.Printf(" (g) %-3v (%v)", gas, closure.Gas)
+
+		if !closure.UseGas(gas) {
+			self.Endl()
+
+			err := fmt.Errorf("Insufficient gas for %v. req %v has %v", op, gas, closure.Gas)
+
+			closure.UseGas(closure.Gas)
+
+			return closure.Return(nil), err
+		}
+
+		mem.Resize(newMemSize.Uint64())
+
+		switch op {
+		case LOG:
+			stack.Print()
+			mem.Print()
+			// 0x20 range
+		case ADD:
+			require(2)
+			x, y := stack.Popn()
+			self.Printf(" %v + %v", y, x)
+
+			base.Add(y, x)
+
+			U256(base)
+
+			self.Printf(" = %v", base)
+			// Pop result back on the stack
+			stack.Push(base)
+		case SUB:
+			require(2)
+			x, y := stack.Popn()
+			self.Printf(" %v - %v", y, x)
+
+			base.Sub(y, x)
+
+			U256(base)
+
+			self.Printf(" = %v", base)
+			// Pop result back on the stack
+			stack.Push(base)
+		case MUL:
+			require(2)
+			x, y := stack.Popn()
+			self.Printf(" %v * %v", y, x)
+
+			base.Mul(y, x)
+
+			U256(base)
+
+			self.Printf(" = %v", base)
+			// Pop result back on the stack
+			stack.Push(base)
+		case DIV:
+			require(2)
+			x, y := stack.Pop(), stack.Pop()
+			self.Printf(" %v / %v", x, y)
+
+			if y.Cmp(ethutil.Big0) != 0 {
+				base.Div(x, y)
+			}
+
+			U256(base)
+
+			self.Printf(" = %v", base)
+			// Pop result back on the stack
+			stack.Push(base)
+		case SDIV:
+			require(2)
+			x, y := S256(stack.Pop()), S256(stack.Pop())
+
+			self.Printf(" %v / %v", x, y)
+
+			if y.Cmp(ethutil.Big0) == 0 {
+				base.Set(ethutil.Big0)
+			} else {
+				n := new(big.Int)
+				if new(big.Int).Mul(x, y).Cmp(ethutil.Big0) < 0 {
+					n.SetInt64(-1)
+				} else {
+					n.SetInt64(1)
+				}
+
+				base.Div(x.Abs(x), y.Abs(y)).Mul(base, n)
+
+				U256(base)
+			}
+
+			self.Printf(" = %v", base)
+			stack.Push(base)
+		case MOD:
+			require(2)
+			x, y := stack.Pop(), stack.Pop()
+
+			self.Printf(" %v %% %v", x, y)
+
+			if y.Cmp(ethutil.Big0) == 0 {
+				base.Set(ethutil.Big0)
+			} else {
+				base.Mod(x, y)
+			}
+
+			U256(base)
+
+			self.Printf(" = %v", base)
+			stack.Push(base)
+		case SMOD:
+			require(2)
+			x, y := S256(stack.Pop()), S256(stack.Pop())
+
+			self.Printf(" %v %% %v", x, y)
+
+			if y.Cmp(ethutil.Big0) == 0 {
+				base.Set(ethutil.Big0)
+			} else {
+				n := new(big.Int)
+				if x.Cmp(ethutil.Big0) < 0 {
+					n.SetInt64(-1)
+				} else {
+					n.SetInt64(1)
+				}
+
+				base.Mod(x.Abs(x), y.Abs(y)).Mul(base, n)
+
+				U256(base)
+			}
+
+			self.Printf(" = %v", base)
+			stack.Push(base)
+
+		case EXP:
+			require(2)
+			x, y := stack.Popn()
+
+			self.Printf(" %v ** %v", y, x)
+
+			base.Exp(y, x, Pow256)
+
+			U256(base)
+
+			self.Printf(" = %v", base)
+
+			stack.Push(base)
+		case NEG:
+			require(1)
+			base.Sub(Pow256, stack.Pop())
+
+			base = U256(base)
+
+			stack.Push(base)
+		case LT:
+			require(2)
+			x, y := stack.Popn()
+			self.Printf(" %v < %v", y, x)
+			// x < y
+			if y.Cmp(x) < 0 {
+				stack.Push(ethutil.BigTrue)
+			} else {
+				stack.Push(ethutil.BigFalse)
+			}
+		case GT:
+			require(2)
+			x, y := stack.Popn()
+			self.Printf(" %v > %v", y, x)
+
+			// x > y
+			if y.Cmp(x) > 0 {
+				stack.Push(ethutil.BigTrue)
+			} else {
+				stack.Push(ethutil.BigFalse)
+			}
+
+		case SLT:
+			require(2)
+			y, x := S256(stack.Pop()), S256(stack.Pop())
+			self.Printf(" %v < %v", y, x)
+			// x < y
+			if y.Cmp(S256(x)) < 0 {
+				stack.Push(ethutil.BigTrue)
+			} else {
+				stack.Push(ethutil.BigFalse)
+			}
+		case SGT:
+			require(2)
+			y, x := S256(stack.Pop()), S256(stack.Pop())
+			self.Printf(" %v > %v", y, x)
+
+			// x > y
+			if y.Cmp(x) > 0 {
+				stack.Push(ethutil.BigTrue)
+			} else {
+				stack.Push(ethutil.BigFalse)
+			}
+
+		case EQ:
+			require(2)
+			x, y := stack.Popn()
+			self.Printf(" %v == %v", y, x)
+
+			// x == y
+			if x.Cmp(y) == 0 {
+				stack.Push(ethutil.BigTrue)
+			} else {
+				stack.Push(ethutil.BigFalse)
+			}
+		case NOT:
+			require(1)
+			x := stack.Pop()
+			if x.Cmp(ethutil.BigFalse) > 0 {
+				stack.Push(ethutil.BigFalse)
+			} else {
+				stack.Push(ethutil.BigTrue)
+			}
+
+			// 0x10 range
+		case AND:
+			require(2)
+			x, y := stack.Popn()
+			self.Printf(" %v & %v", y, x)
+
+			stack.Push(base.And(y, x))
+		case OR:
+			require(2)
+			x, y := stack.Popn()
+			self.Printf(" %v | %v", y, x)
+
+			stack.Push(base.Or(y, x))
+		case XOR:
+			require(2)
+			x, y := stack.Popn()
+			self.Printf(" %v ^ %v", y, x)
+
+			stack.Push(base.Xor(y, x))
+		case BYTE:
+			require(2)
+			val, th := stack.Popn()
+
+			if th.Cmp(big.NewInt(32)) < 0 {
+				byt := big.NewInt(int64(ethutil.LeftPadBytes(val.Bytes(), 32)[th.Int64()]))
+
+				base.Set(byt)
+			} else {
+				base.Set(ethutil.BigFalse)
+			}
+
+			self.Printf(" => 0x%x", base.Bytes())
+
+			stack.Push(base)
+		case ADDMOD:
+			require(3)
+
+			x := stack.Pop()
+			y := stack.Pop()
+			z := stack.Pop()
+
+			base.Add(x, y)
+			base.Mod(base, z)
+
+			U256(base)
+
+			self.Printf(" = %v", base)
+
+			stack.Push(base)
+		case MULMOD:
+			require(3)
+
+			x := stack.Pop()
+			y := stack.Pop()
+			z := stack.Pop()
+
+			base.Mul(x, y)
+			base.Mod(base, z)
+
+			U256(base)
+
+			self.Printf(" = %v", base)
+
+			stack.Push(base)
+
+			// 0x20 range
+		case SHA3:
+			require(2)
+			size, offset := stack.Popn()
+			data := ethcrypto.Sha3(mem.Get(offset.Int64(), size.Int64()))
+
+			stack.Push(ethutil.BigD(data))
+
+			self.Printf(" => %x", data)
+			// 0x30 range
+		case ADDRESS:
+			stack.Push(ethutil.BigD(closure.Address()))
+
+			self.Printf(" => %x", closure.Address())
+		case BALANCE:
+			require(1)
+
+			addr := stack.Pop().Bytes()
+			balance := state.GetBalance(addr)
+
+			stack.Push(balance)
+
+			self.Printf(" => %v (%x)", balance, addr)
+		case ORIGIN:
+			origin := self.env.Origin()
+
+			stack.Push(ethutil.BigD(origin))
+
+			self.Printf(" => %x", origin)
+		case CALLER:
+			caller := closure.caller.Address()
+			stack.Push(ethutil.BigD(caller))
+
+			self.Printf(" => %x", caller)
+		case CALLVALUE:
+			value := closure.exe.value
+
+			stack.Push(value)
+
+			self.Printf(" => %v", value)
+		case CALLDATALOAD:
+			require(1)
+			var (
+				offset  = stack.Pop()
+				data    = make([]byte, 32)
+				lenData = big.NewInt(int64(len(closure.Args)))
+			)
+
+			if lenData.Cmp(offset) >= 0 {
+				length := new(big.Int).Add(offset, ethutil.Big32)
+				length = ethutil.BigMin(length, lenData)
+
+				copy(data, closure.Args[offset.Int64():length.Int64()])
+			}
+
+			self.Printf(" => 0x%x", data)
+
+			stack.Push(ethutil.BigD(data))
+		case CALLDATASIZE:
+			l := int64(len(closure.Args))
+			stack.Push(big.NewInt(l))
+
+			self.Printf(" => %d", l)
+		case CALLDATACOPY:
+			var (
+				size = int64(len(closure.Args))
+				mOff = stack.Pop().Int64()
+				cOff = stack.Pop().Int64()
+				l    = stack.Pop().Int64()
+			)
+
+			if cOff > size {
+				cOff = 0
+				l = 0
+			} else if cOff+l > size {
+				l = 0
+			}
+
+			code := closure.Args[cOff : cOff+l]
+
+			mem.Set(mOff, l, code)
+		case CODESIZE, EXTCODESIZE:
+			var code []byte
+			if op == EXTCODESIZE {
+				addr := stack.Pop().Bytes()
+
+				code = state.GetCode(addr)
+			} else {
+				code = closure.Code
+			}
+
+			l := big.NewInt(int64(len(code)))
+			stack.Push(l)
+
+			self.Printf(" => %d", l)
+		case CODECOPY, EXTCODECOPY:
+			var code []byte
+			if op == EXTCODECOPY {
+				addr := stack.Pop().Bytes()
+
+				code = state.GetCode(addr)
+			} else {
+				code = closure.Code
+			}
+
+			var (
+				size = int64(len(code))
+				mOff = stack.Pop().Int64()
+				cOff = stack.Pop().Int64()
+				l    = stack.Pop().Int64()
+			)
+
+			if cOff > size {
+				cOff = 0
+				l = 0
+			} else if cOff+l > size {
+				l = 0
+			}
+
+			codeCopy := code[cOff : cOff+l]
+
+			mem.Set(mOff, l, codeCopy)
+		case GASPRICE:
+			stack.Push(closure.Price)
+
+			self.Printf(" => %v", closure.Price)
+
+			// 0x40 range
+		case PREVHASH:
+			prevHash := self.env.PrevHash()
+
+			stack.Push(ethutil.BigD(prevHash))
+
+			self.Printf(" => 0x%x", prevHash)
+		case COINBASE:
+			coinbase := self.env.Coinbase()
+
+			stack.Push(ethutil.BigD(coinbase))
+
+			self.Printf(" => 0x%x", coinbase)
+		case TIMESTAMP:
+			time := self.env.Time()
+
+			stack.Push(big.NewInt(time))
+
+			self.Printf(" => 0x%x", time)
+		case NUMBER:
+			number := self.env.BlockNumber()
+
+			stack.Push(number)
+
+			self.Printf(" => 0x%x", number.Bytes())
+		case DIFFICULTY:
+			difficulty := self.env.Difficulty()
+
+			stack.Push(difficulty)
+
+			self.Printf(" => 0x%x", difficulty.Bytes())
+		case GASLIMIT:
+			stack.Push(self.env.GasLimit())
+
+			// 0x50 range
+		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:
+			a := big.NewInt(int64(op) - int64(PUSH1) + 1)
+			pc.Add(pc, ethutil.Big1)
+			data := closure.Gets(pc, a)
+			val := ethutil.BigD(data.Bytes())
+			// Push value to stack
+			stack.Push(val)
+			pc.Add(pc, a.Sub(a, big.NewInt(1)))
+
+			step += int(op) - int(PUSH1) + 1
+
+			self.Printf(" => 0x%x", data.Bytes())
+		case POP:
+			require(1)
+			stack.Pop()
+		case DUP1, DUP2, DUP3, DUP4, DUP5, DUP6, DUP7, DUP8, DUP9, DUP10, DUP11, DUP12, DUP13, DUP14, DUP15, DUP16:
+			n := int(op - DUP1 + 1)
+			v := stack.Dupn(n)
+
+			self.Printf(" => [%d] 0x%x", n, stack.Peek().Bytes())
+
+			if OpCode(closure.Get(new(big.Int).Add(pc, ethutil.Big1)).Uint()) == POP && OpCode(closure.Get(new(big.Int).Add(pc, big.NewInt(2))).Uint()) == POP {
+				fmt.Println(toValue(v))
+			}
+		case SWAP1, SWAP2, SWAP3, SWAP4, SWAP5, SWAP6, SWAP7, SWAP8, SWAP9, SWAP10, SWAP11, SWAP12, SWAP13, SWAP14, SWAP15, SWAP16:
+			n := int(op - SWAP1 + 2)
+			x, y := stack.Swapn(n)
+
+			self.Printf(" => [%d] %x [0] %x", n, x.Bytes(), y.Bytes())
+		case MLOAD:
+			require(1)
+			offset := stack.Pop()
+			val := ethutil.BigD(mem.Get(offset.Int64(), 32))
+			stack.Push(val)
+
+			self.Printf(" => 0x%x", val.Bytes())
+		case MSTORE: // Store the value at stack top-1 in to memory at location stack top
+			require(2)
+			// Pop value of the stack
+			val, mStart := stack.Popn()
+			mem.Set(mStart.Int64(), 32, ethutil.BigToBytes(val, 256))
+
+			self.Printf(" => 0x%x", val)
+		case MSTORE8:
+			require(2)
+			off := stack.Pop()
+			val := stack.Pop()
+
+			mem.store[off.Int64()] = byte(val.Int64() & 0xff)
+
+			self.Printf(" => [%v] 0x%x", off, val)
+		case SLOAD:
+			require(1)
+			loc := stack.Pop()
+			val := ethutil.BigD(state.GetState(closure.Address(), loc.Bytes()))
+			stack.Push(val)
+
+			self.Printf(" {0x%x : 0x%x}", loc.Bytes(), val.Bytes())
+		case SSTORE:
+			require(2)
+			val, loc := stack.Popn()
+			state.SetState(closure.Address(), loc.Bytes(), val)
+
+			// Debug sessions are allowed to run without message
+			if closure.message != nil {
+				closure.message.AddStorageChange(loc.Bytes())
+			}
+
+			self.Printf(" {0x%x : 0x%x}", loc.Bytes(), val.Bytes())
+		case JUMP:
+			require(1)
+
+			jump(stack.Pop())
+
+			continue
+		case JUMPI:
+			require(2)
+			cond, pos := stack.Popn()
+
+			if cond.Cmp(ethutil.BigTrue) >= 0 {
+				jump(pos)
+
+				continue
+			}
+
+		case JUMPDEST:
+		case PC:
+			stack.Push(pc)
+		case MSIZE:
+			stack.Push(big.NewInt(int64(mem.Len())))
+		case GAS:
+			stack.Push(closure.Gas)
+			// 0x60 range
+		case CREATE:
+			require(3)
+
+			var (
+				err          error
+				value        = stack.Pop()
+				size, offset = stack.Popn()
+				input        = mem.Get(offset.Int64(), size.Int64())
+				gas          = new(big.Int).Set(closure.Gas)
+
+				// Snapshot the current stack so we are able to
+				// revert back to it later.
+				//snapshot = self.env.State().Copy()
+			)
+
+			// Generate a new address
+			n := state.GetNonce(closure.Address())
+			addr := ethcrypto.CreateAddress(closure.Address(), n)
+			state.SetNonce(closure.Address(), n+1)
+
+			self.Printf(" (*) %x", addr).Endl()
+
+			closure.UseGas(closure.Gas)
+
+			msg := NewExecution(self, addr, input, gas, closure.Price, value)
+			ret, err := msg.Create(closure)
+			if err != nil {
+				stack.Push(ethutil.BigFalse)
+
+				// Revert the state as it was before.
+				//self.env.State().Set(snapshot)
+
+				self.Printf("CREATE err %v", err)
+			} else {
+				msg.object.Code = ret
+
+				stack.Push(ethutil.BigD(addr))
+			}
+
+			self.Endl()
+
+			// Debug hook
+			if self.Dbg != nil {
+				self.Dbg.SetCode(closure.Code)
+			}
+		case CALL, CALLCODE:
+			require(7)
+
+			self.Endl()
+
+			gas := stack.Pop()
+			// Pop gas and value of the stack.
+			value, addr := stack.Popn()
+			// Pop input size and offset
+			inSize, inOffset := stack.Popn()
+			// Pop return size and offset
+			retSize, retOffset := stack.Popn()
+
+			// Get the arguments from the memory
+			args := mem.Get(inOffset.Int64(), inSize.Int64())
+
+			var executeAddr []byte
+			if op == CALLCODE {
+				executeAddr = closure.Address()
+			} else {
+				executeAddr = addr.Bytes()
+			}
+
+			msg := NewExecution(self, executeAddr, args, gas, closure.Price, value)
+			ret, err := msg.Exec(addr.Bytes(), closure)
+			if err != nil {
+				stack.Push(ethutil.BigFalse)
+
+				vmlogger.Debugln(err)
+			} else {
+				stack.Push(ethutil.BigTrue)
+
+				mem.Set(retOffset.Int64(), retSize.Int64(), ret)
+			}
+			self.Printf("resume %x", closure.Address())
+
+			// Debug hook
+			if self.Dbg != nil {
+				self.Dbg.SetCode(closure.Code)
+			}
+
+		case RETURN:
+			require(2)
+			size, offset := stack.Popn()
+			ret := mem.Get(offset.Int64(), size.Int64())
+
+			self.Printf(" => (%d) 0x%x", len(ret), ret).Endl()
+
+			return closure.Return(ret), nil
+		case SUICIDE:
+			require(1)
+
+			receiver := state.GetOrNewStateObject(stack.Pop().Bytes())
+
+			receiver.AddAmount(state.GetBalance(closure.Address()))
+			state.Delete(closure.Address())
+
+			fallthrough
+		case STOP: // Stop the closure
+			self.Endl()
+
+			return closure.Return(nil), nil
+		default:
+			vmlogger.Debugf("(pc) %-3v Invalid opcode %x\n", pc, op)
+
+			//panic(fmt.Sprintf("Invalid opcode %x", op))
+			closure.ReturnGas(big.NewInt(1), nil)
+
+			return closure.Return(nil), fmt.Errorf("Invalid opcode %x", op)
+		}
+
+		pc.Add(pc, ethutil.Big1)
+
+		self.Endl()
+
+		if self.Dbg != nil {
+			for _, instrNo := range self.Dbg.BreakPoints() {
+				if pc.Cmp(big.NewInt(instrNo)) == 0 {
+					self.Stepping = true
+
+					if !self.Dbg.BreakHook(prevStep, op, mem, stack, state.GetStateObject(closure.Address())) {
+						return nil, nil
+					}
+				} else if self.Stepping {
+					if !self.Dbg.StepHook(prevStep, op, mem, stack, state.GetStateObject(closure.Address())) {
+						return nil, nil
+					}
+				}
+			}
+		}
+
+	}
+}
+
+func (self *DebugVm) Printf(format string, v ...interface{}) VirtualMachine {
+	if self.logTy == LogTyPretty {
+		self.logStr += fmt.Sprintf(format, v...)
+	}
+
+	return self
+}
+
+func (self *DebugVm) Endl() VirtualMachine {
+	if self.logTy == LogTyPretty {
+		vmlogger.Debugln(self.logStr)
+		self.logStr = ""
+	}
+
+	return self
+}
+
+func (self *DebugVm) Env() Environment {
+	return self.env
+}
+
+func (self *DebugVm) Depth() int {
+	return self.depth
+}
diff --git a/vm/vm_test.go b/vm/vm_test.go
new file mode 100644
index 000000000..047b76121
--- /dev/null
+++ b/vm/vm_test.go
@@ -0,0 +1,155 @@
+package vm
+
+import (
+	"bytes"
+	"fmt"
+	"io/ioutil"
+	"log"
+	"math/big"
+	"os"
+	"testing"
+
+	"github.com/ethereum/eth-go/ethcrypto"
+	"github.com/ethereum/eth-go/ethlog"
+	"github.com/ethereum/eth-go/ethstate"
+	"github.com/ethereum/eth-go/ethtrie"
+	"github.com/ethereum/eth-go/ethutil"
+)
+
+type TestEnv struct {
+}
+
+func (self TestEnv) Origin() []byte        { return nil }
+func (self TestEnv) BlockNumber() *big.Int { return nil }
+func (self TestEnv) BlockHash() []byte     { return nil }
+func (self TestEnv) PrevHash() []byte      { return nil }
+func (self TestEnv) Coinbase() []byte      { return nil }
+func (self TestEnv) Time() int64           { return 0 }
+func (self TestEnv) Difficulty() *big.Int  { return nil }
+func (self TestEnv) Value() *big.Int       { return nil }
+
+// This is likely to fail if anything ever gets looked up in the state trie :-)
+func (self TestEnv) State() *ethstate.State { return ethstate.New(ethtrie.New(nil, "")) }
+
+const mutcode = `
+var x = 0;
+for i := 0; i < 10; i++ {
+	x = i
+}
+
+return x`
+
+func setup(level ethlog.LogLevel, typ Type) (*Closure, VirtualMachine) {
+	code, err := ethutil.Compile(mutcode, true)
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	// Pipe output to /dev/null
+	ethlog.AddLogSystem(ethlog.NewStdLogSystem(ioutil.Discard, log.LstdFlags, level))
+
+	ethutil.ReadConfig(".ethtest", "/tmp/ethtest", "")
+
+	stateObject := ethstate.NewStateObject([]byte{'j', 'e', 'f', 'f'})
+	callerClosure := NewClosure(nil, stateObject, stateObject, code, big.NewInt(1000000), big.NewInt(0))
+
+	return callerClosure, New(TestEnv{}, typ)
+}
+
+func TestDebugVm(t *testing.T) {
+	closure, vm := setup(ethlog.DebugLevel, DebugVmTy)
+	ret, _, e := closure.Call(vm, nil)
+	if e != nil {
+		fmt.Println("error", e)
+	}
+
+	if ret[len(ret)-1] != 9 {
+		t.Errorf("Expected VM to return 9, got", ret, "instead.")
+	}
+}
+
+func TestVm(t *testing.T) {
+	closure, vm := setup(ethlog.DebugLevel, StandardVmTy)
+	ret, _, e := closure.Call(vm, nil)
+	if e != nil {
+		fmt.Println("error", e)
+	}
+
+	if ret[len(ret)-1] != 9 {
+		t.Errorf("Expected VM to return 9, got", ret, "instead.")
+	}
+}
+
+func BenchmarkDebugVm(b *testing.B) {
+	closure, vm := setup(ethlog.InfoLevel, DebugVmTy)
+
+	b.ResetTimer()
+
+	for i := 0; i < b.N; i++ {
+		closure.Call(vm, nil)
+	}
+}
+
+func BenchmarkVm(b *testing.B) {
+	closure, vm := setup(ethlog.InfoLevel, StandardVmTy)
+
+	b.ResetTimer()
+
+	for i := 0; i < b.N; i++ {
+		closure.Call(vm, nil)
+	}
+}
+
+func RunCode(mutCode string, typ Type) []byte {
+	code, err := ethutil.Compile(mutCode, true)
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	ethlog.AddLogSystem(ethlog.NewStdLogSystem(os.Stdout, log.LstdFlags, ethlog.InfoLevel))
+
+	ethutil.ReadConfig(".ethtest", "/tmp/ethtest", "")
+
+	stateObject := ethstate.NewStateObject([]byte{'j', 'e', 'f', 'f'})
+	closure := NewClosure(nil, stateObject, stateObject, code, big.NewInt(1000000), big.NewInt(0))
+
+	vm := New(TestEnv{}, typ)
+	ret, _, e := closure.Call(vm, nil)
+	if e != nil {
+		fmt.Println(e)
+	}
+
+	return ret
+}
+
+func TestBuildInSha256(t *testing.T) {
+	ret := RunCode(`
+	var in = 42
+	var out = 0
+
+	call(0x2, 0, 10000, in, out)
+
+	return out
+	`, DebugVmTy)
+
+	exp := ethcrypto.Sha256(ethutil.LeftPadBytes([]byte{42}, 32))
+	if bytes.Compare(ret, exp) != 0 {
+		t.Errorf("Expected %x, got %x", exp, ret)
+	}
+}
+
+func TestBuildInRipemd(t *testing.T) {
+	ret := RunCode(`
+	var in = 42
+	var out = 0
+
+	call(0x3, 0, 10000, in, out)
+
+	return out
+	`, DebugVmTy)
+
+	exp := ethutil.RightPadBytes(ethcrypto.Ripemd160(ethutil.LeftPadBytes([]byte{42}, 32)), 32)
+	if bytes.Compare(ret, exp) != 0 {
+		t.Errorf("Expected %x, got %x", exp, ret)
+	}
+}