package ethvm
import (
"fmt"
"math/big"
"github.com/ethereum/eth-go/ethcrypto"
"github.com/ethereum/eth-go/ethstate"
"github.com/ethereum/eth-go/ethutil"
)
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)
}
type Vm struct {
env Environment
Verbose bool
logTy byte
logStr string
err error
// Debugging
Dbg Debugger
BreakPoints []int64
Stepping bool
Fn string
Recoverable bool
}
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)
}
func New(env Environment) *Vm {
lt := LogTyPretty
if ethutil.Config.Diff {
lt = LogTyDiff
}
return &Vm{env: env, logTy: lt, Recoverable: true}
}
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)
}
func (self *Vm) RunClosure(closure *Closure) (ret []byte, err error) {
if self.Recoverable {
// Recover from any require exception
defer func() {
if r := recover(); r != nil {
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)
var (
op OpCode
mem = &Memory{}
stack = NewStack()
pc = big.NewInt(0)
step = 0
prevStep = 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 {
prevStep = step
// The base for all big integer arithmetic
base := new(big.Int)
step++
// Get the memory location of pc
val := closure.Get(pc)
// Get the opcode (it must be an opcode!)
op = OpCode(val.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:
closure.object.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)
}
}
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
}
self.Printf("(pc) %-3d -o- %-14s", pc, op.String())
self.Printf(" (g) %-3v (%v)", gas, closure.Gas)
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)
ensure256(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)
ensure256(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)
ensure256(base)
self.Printf(" = %v", base)
// Pop result back on the stack
stack.Push(base)
case DIV:
require(2)
x, y := stack.Popn()
self.Printf(" %v / %v", y, x)
if x.Cmp(ethutil.Big0) != 0 {
base.Div(y, x)
}
ensure256(base)
self.Printf(" = %v", base)
// Pop result back on the stack
stack.Push(base)
case SDIV:
require(2)
x, y := stack.Popn()
self.Printf(" %v / %v", y, x)
if x.Cmp(ethutil.Big0) != 0 {
base.Div(y, x)
}
ensure256(base)
self.Printf(" = %v", base)
// Pop result back on the stack
stack.Push(base)
case MOD:
require(2)
x, y := stack.Popn()
self.Printf(" %v %% %v", y, x)
base.Mod(y, x)
ensure256(base)
self.Printf(" = %v", base)
stack.Push(base)
case SMOD:
require(2)
x, y := stack.Popn()
self.Printf(" %v %% %v", y, x)
base.Mod(y, x)
ensure256(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)
ensure256(base)
self.Printf(" = %v", base)
stack.Push(base)
case NEG:
require(1)
base.Sub(Pow256, stack.Pop())
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)
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 SGT:
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 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 && th.Cmp(big.NewInt(int64(len(val.Bytes())))) < 0 {
byt := big.NewInt(int64(ethutil.LeftPadBytes(val.Bytes(), 32)[th.Int64()]))
stack.Push(byt)
self.Printf(" => 0x%x", byt.Bytes())
} 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)
ensure256(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)
ensure256(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 := self.env.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 := self.env.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 == EXTCODECOPY {
addr := stack.Pop().Bytes()
code = self.env.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 = 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)
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:
// 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 := 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 := closure.GetStorage(loc)
stack.Push(val.BigInt())
self.Printf(" {0x%x : 0x%x}", loc.Bytes(), val.Bytes())
case SSTORE:
require(2)
val, loc := stack.Popn()
closure.SetStorage(loc, ethutil.NewValue(val))
closure.message.AddStorageChange(loc.Bytes())
self.Printf(" {0x%x : 0x%x}", loc.Bytes(), val.Bytes())
case JUMP:
require(1)
pc = stack.Pop()
// Reduce pc by one because of the increment that's at the end of this for loop
self.Printf(" ~> %v", pc).Endl()
continue
case JUMPI:
require(2)
cond, pos := stack.Popn()
if cond.Cmp(ethutil.BigTrue) >= 0 {
pc = pos
if OpCode(closure.Get(pc).Uint()) != JUMPDEST {
return closure.Return(nil), fmt.Errorf("JUMP missed JUMPDEST %v", pc)
}
continue
} else {
self.Printf(" (f)")
}
case JUMPDEST:
self.Printf(" ~> %v (t)", pc).Endl()
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
addr := ethcrypto.CreateAddress(closure.Address(), closure.object.Nonce)
//for i := uint64(0); self.env.State().GetStateObject(addr) != nil; i++ {
// ethcrypto.CreateAddress(closure.Address(), closure.object.Nonce+i)
//}
closure.object.Nonce++
self.Printf(" (*) %x", addr).Endl()
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)
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())
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)
}
// 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 := self.env.State().GetOrNewStateObject(stack.Pop().Bytes())
receiver.AddAmount(closure.object.Balance)
closure.object.MarkForDeletion()
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))
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, closure.Object()) {
return nil, nil
}
} else if self.Stepping {
if !self.Dbg.StepHook(prevStep, op, mem, stack, closure.Object()) {
return nil, nil
}
}
}
}
}
}
func (self *Vm) Printf(format string, v ...interface{}) *Vm {
if self.Verbose && self.logTy == LogTyPretty {
self.logStr += fmt.Sprintf(format, v...)
}
return self
}
func (self *Vm) Endl() *Vm {
if self.Verbose && self.logTy == LogTyPretty {
vmlogger.Debugln(self.logStr)
self.logStr = ""
}
return self
}
func ensure256(x *big.Int) {
//max, _ := big.NewInt(0).SetString("115792089237316195423570985008687907853269984665640564039457584007913129639936", 0)
//if x.Cmp(max) >= 0 {
d := big.NewInt(1)
d.Lsh(d, 256).Sub(d, big.NewInt(1))
x.And(x, d)
//}
// Could have done this with an OR, but big ints are costly.
if x.Cmp(new(big.Int)) < 0 {
x.SetInt64(0)
}
}
type Execution struct {
vm *Vm
closure *Closure
address, input []byte
gas, price, value *big.Int
object *ethstate.StateObject
}
func NewExecution(vm *Vm, 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) {
msg := self.vm.env.State().Manifest().AddMessage(ðstate.Message{
To: self.address, From: caller.Address(),
Input: self.input,
Origin: self.vm.env.Origin(),
Block: self.vm.env.BlockHash(), Timestamp: self.vm.env.Time(), Coinbase: self.vm.env.Coinbase(), Number: self.vm.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 := self.vm.env.State().GetOrNewStateObject(self.address)
self.object = stateObject
caller.Object().SubAmount(self.value)
stateObject.AddAmount(self.value)
if p := Precompiled[ethutil.BigD(codeAddr).Uint64()]; p != nil {
if self.gas.Cmp(p.Gas) >= 0 {
ret = p.Call(self.input)
}
} else {
// Retrieve the executing code
code := self.vm.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
}
}
return
}
// 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
}