Refactored VM to two separate VMs; std & debug

Standard VM should be about 10x faster than the debug VM. Some error
checking has been removed, all of the log statements and therefor quite
some unnecessary if-statements.

ethchain/state_transition.go

@@ -224,7 +224,7 @@ func (self *StateTransition) TransitionState() (err error) {
 		// script section for the state object.
 		self.data = nil
 
-		code, err := self.Eval(msg, receiver.Init(), receiver, "init")
+		code, err := self.Eval(msg, receiver.Init(), receiver)
 		if err != nil {
 			self.state.Set(snapshot)
 
@@ -235,7 +235,7 @@ func (self *StateTransition) TransitionState() (err error) {
 		msg.Output = code
 	} else {
 		if len(receiver.Code) > 0 {
-			ret, err := self.Eval(msg, receiver.Code, receiver, "code")
+			ret, err := self.Eval(msg, receiver.Code, receiver)
 			if err != nil {
 				self.state.Set(snapshot)
 
@@ -262,7 +262,7 @@ func (self *StateTransition) transferValue(sender, receiver *ethstate.StateObjec
 	return nil
 }
 
-func (self *StateTransition) Eval(msg *ethstate.Message, script []byte, context *ethstate.StateObject, typ string) (ret []byte, err error) {
+func (self *StateTransition) Eval(msg *ethstate.Message, script []byte, context *ethstate.StateObject) (ret []byte, err error) {
 	var (
 		transactor    = self.Sender()
 		state         = self.state
@@ -270,9 +270,7 @@ func (self *StateTransition) Eval(msg *ethstate.Message, script []byte, context
 		callerClosure = ethvm.NewClosure(msg, transactor, context, script, self.gas, self.gasPrice)
 	)
 
-	vm := ethvm.New(env)
-	vm.Verbose = true
-	vm.Fn = typ
+	vm := ethvm.New(env, ethvm.Type(ethutil.Config.VmType))
 
 	ret, _, err = callerClosure.Call(vm, self.tx.Data)
 

ethpipe/pipe.go

@@ -58,8 +58,7 @@ func (self *Pipe) ExecuteObject(object *Object, data []byte, value, gas, price *
 
 	self.Vm.State = self.World().State().Copy()
 
-	vm := ethvm.New(NewEnv(self.Vm.State, block, value.BigInt(), initiator.Address()))
-	vm.Verbose = true
+	vm := ethvm.New(NewEnv(self.Vm.State, block, value.BigInt(), initiator.Address()), ethvm.Type(ethutil.Config.VmType))
 
 	msg := ethvm.NewExecution(vm, object.Address(), data, gas.BigInt(), price.BigInt(), value.BigInt())
 	ret, err := msg.Exec(object.Address(), initiator)

ethutil/config.go

@@ -17,6 +17,7 @@ type ConfigManager struct {
 	Diff     bool
 	DiffType string
 	Paranoia bool
+	VmType   int
 
 	conf *globalconf.GlobalConf
 }

ethvm/closure.go

@@ -58,6 +58,26 @@ 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)
@@ -76,7 +96,7 @@ func (c *Closure) Address() []byte {
 	return c.object.Address()
 }
 
-func (c *Closure) Call(vm *Vm, args []byte) ([]byte, *big.Int, error) {
+func (c *Closure) Call(vm VirtualMachine, args []byte) ([]byte, *big.Int, error) {
 	c.Args = args
 
 	ret, err := vm.RunClosure(c)

ethvm/common.go

 package ethvm
 
 import (
+	"math/big"
+
 	"github.com/ethereum/eth-go/ethlog"
 	"github.com/ethereum/eth-go/ethutil"
-	"math/big"
 )
 
 var vmlogger = ethlog.NewLogger("VM")
 
+type Type int
+
+const (
+	StandardVmTy Type = iota
+	DebugVmTy
+
+	MaxVmTy
+)
+
 var (
 	GasStep    = big.NewInt(1)
 	GasSha     = big.NewInt(20)
@@ -24,4 +34,32 @@ var (
 
 	LogTyPretty byte = 0x1
 	LogTyDiff   byte = 0x2
+
+	To256 = ethutil.To256
 )
+
+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
+}

ethvm/debugger.go

+package ethvm
+
+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)
+}

ethvm/environment.go

+package ethvm
+
+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
+	Value() *big.Int
+	BlockHash() []byte
+}
+
+type Object interface {
+	GetStorage(key *big.Int) *ethutil.Value
+	SetStorage(key *big.Int, value *ethutil.Value)
+}

ethvm/execution.go

+package ethvm
+
+import (
+	"fmt"
+	"math/big"
+
+	"github.com/ethereum/eth-go/ethstate"
+	"github.com/ethereum/eth-go/ethutil"
+)
+
+type Execution struct {
+	vm                VirtualMachine
+	closure           *Closure
+	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) (ret []byte, err error) {
+	env := self.vm.Env()
+
+	snapshot := env.State().Copy()
+
+	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)
+
+		// Precompiled contracts (address.go) 1, 2 & 3.
+		if p := Precompiled[ethutil.BigD(codeAddr).Uint64()]; p != nil {
+			if self.gas.Cmp(p.Gas) >= 0 {
+				ret = p.Call(self.input)
+			}
+		} else {
+			if self.vm.Depth() == MaxCallDepth {
+				return nil, fmt.Errorf("Max call depth exceeded (%d)", MaxCallDepth)
+			}
+
+			// Retrieve the executing code
+			code := env.State().GetCode(codeAddr)
+
+			// Create a new callable closure
+			c := NewClosure(msg, caller, stateObject, code, self.gas, self.price)
+			// Executer the closure and get the return value (if any)
+			ret, _, err = c.Call(self.vm, self.input)
+
+			msg.Output = ret
+		}
+	}
+
+	if err != nil {
+		env.State().Set(snapshot)
+	}
+
+	return
+}

ethvm/types.go

@@ -4,7 +4,7 @@ import (
 	"fmt"
 )
 
-type OpCode int
+type OpCode byte
 
 // Op codes
 const (

ethvm/virtual_machine.go

+package ethvm
+
+type VirtualMachine interface {
+	Env() Environment
+	RunClosure(*Closure) ([]byte, error)
+	Depth() int
+}

ethvm/vm_test.go

@@ -2,9 +2,9 @@ package ethvm
 
 import (
 	"fmt"
+	"io/ioutil"
 	"log"
 	"math/big"
-	"os"
 	"testing"
 
 	"github.com/ethereum/eth-go/ethlog"
@@ -17,6 +17,7 @@ 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 }
@@ -24,20 +25,65 @@ func (self TestEnv) Difficulty() *big.Int   { return nil }
 func (self TestEnv) Value() *big.Int        { return nil }
 func (self TestEnv) State() *ethstate.State { return nil }
 
-func TestVm(t *testing.T) {
-	ethlog.AddLogSystem(ethlog.NewStdLogSystem(os.Stdout, log.LstdFlags, ethlog.LogLevel(4)))
+func setup(level int, typ Type) (*Closure, VirtualMachine) {
+	// Pipe output to /dev/null
+	ethlog.AddLogSystem(ethlog.NewStdLogSystem(ioutil.Discard, log.LstdFlags, ethlog.LogLevel(level)))
 
 	ethutil.ReadConfig(".ethtest", "/tmp/ethtest", "")
 
 	stateObject := ethstate.NewStateObject([]byte{'j', 'e', 'f', 'f'})
-	callerClosure := NewClosure(stateObject, stateObject, []byte{0x60, 0x01}, big.NewInt(1000000), big.NewInt(0))
+	callerClosure := NewClosure(nil, stateObject, stateObject, []byte{
+		PUSH1, 1,
+		PUSH1, 0,
+		MSTORE,
+		PUSH1, 32,
+		PUSH1, 0,
+		RETURN,
+	}, big.NewInt(1000000), big.NewInt(0))
 
-	vm := New(TestEnv{})
-	vm.Verbose = true
+	return callerClosure, New(TestEnv{}, typ)
+}
 
-	ret, _, e := callerClosure.Call(vm, nil)
+func TestDebugVm(t *testing.T) {
+	closure, vm := setup(4, DebugVmTy)
+	ret, _, e := closure.Call(vm, nil)
 	if e != nil {
 		fmt.Println("error", e)
 	}
-	fmt.Println(ret)
+
+	if ret[len(ret)-1] != 1 {
+		t.Errorf("Expected VM to return 1, got", ret, "instead.")
+	}
+}
+
+func TestVm(t *testing.T) {
+	closure, vm := setup(4, StandardVmTy)
+	ret, _, e := closure.Call(vm, nil)
+	if e != nil {
+		fmt.Println("error", e)
+	}
+
+	if ret[len(ret)-1] != 1 {
+		t.Errorf("Expected VM to return 1, got", ret, "instead.")
+	}
+}
+
+func BenchmarkDebugVm(b *testing.B) {
+	closure, vm := setup(3, DebugVmTy)
+
+	b.ResetTimer()
+
+	for i := 0; i < b.N; i++ {
+		closure.Call(vm, nil)
+	}
+}
+
+func BenchmarkVm(b *testing.B) {
+	closure, vm := setup(3, StandardVmTy)
+
+	b.ResetTimer()
+
+	for i := 0; i < b.N; i++ {
+		closure.Call(vm, nil)
+	}
 }