// pow sets d to x ** y and returns z. func (z *Big) pow(x *Big, y *big.Int) *Big { switch { case y.Sign() < 0, (x.ez() || y.Sign() == 0): return z.SetMantScale(1, 0) case y.Cmp(oneInt) == 0: return z.Set(x) case x.ez(): if x.isOdd() { return z.Set(x) } z.form = zero return z } x0 := new(Big).Set(x) y0 := new(big.Int).Set(y) ret := New(1, 0) var odd big.Int for y0.Sign() > 0 { if odd.And(y0, oneInt).Sign() != 0 { ret.Mul(ret, x0) } y0.Rsh(y0, 1) x0.Mul(x0, x0) } *z = *ret return ret }
func TestModAdc(t *testing.T) { A := new(big.Int) B := new(big.Int) C := new(big.Int) Carry := new(big.Int) Mask := new(big.Int) for _, a := range numbers { A.SetUint64(a) for _, b := range numbers { B.SetUint64(b) for width := uint8(1); width < 64; width++ { carry := b c := mod_adc(a, width, &carry) C.Add(A, B) Carry.Rsh(C, uint(width)) expectedCarry := Carry.Uint64() Mask.SetUint64(uint64(1)<<width - 1) C.And(C, Mask) expected := C.Uint64() if c != expected || expectedCarry != carry { t.Fatalf("adc(%d,%d,%d): Expecting %d carry %d but got %d carry %d", a, b, width, expected, expectedCarry, c, carry) } } } } }
func U256(x *big.Int) *big.Int { //if x.Cmp(Big0) < 0 { // return new(big.Int).Add(tt256, x) // } x.And(x, tt256m1) return x }
// Len returns the number of elements in the set. // Its complexity is O(n). func (s *Set) Len() int { var l int zero := big.NewInt(0) v := new(big.Int).Set((*big.Int)(s)) for l = 0; v.Cmp(zero) != 0; l++ { vMinusOne := new(big.Int).Sub(v, big.NewInt(1)) v.And(v, vMinusOne) } return l }
// Size returns the number of integers in the set. // Alogrithm stolen from github.com/kisielk/bigset func (set *BitSet) Size() int { var l int zero := big.NewInt(0) v := new(big.Int).Set(set.data) for l = 0; v.Cmp(zero) != 0; l++ { vMinusOne := new(big.Int).Sub(v, big.NewInt(1)) v.And(v, vMinusOne) } return l }
func SetEntry(hv *big.Int, numBits int, entry *Entry) { mask := new(big.Int) for i := 0; i < numBits; i++ { mask.SetBit(mask, i, 1) } mv := uint64(mask.And(mask, hv).Int64()) hv2 := new(big.Int).Rsh(hv, uint(numBits)) entry.MValue = mv entry.Rank = rank(hv2) }
// NetworkAddress returns an IPv6Network of the IPv6Addr's network address. func (ipv6 IPv6Addr) NetworkAddress() IPv6Network { addr := new(big.Int) addr.SetBytes((*ipv6.Address).Bytes()) mask := new(big.Int) mask.SetBytes(*ipv6.NetIPMask()) netAddr := new(big.Int) netAddr.And(addr, mask) return IPv6Network(netAddr) }
// z.Int() returns a representation of z, truncated to be an int of // length bits. Valid values for bits are 8, 16, 32, 64. Result is // otherwise undefined If a truncation occurs, the decimal part is // dropped and the conversion continues as usual. truncation will be // true If an overflow occurs, the result is equivelant to a cast of // the form int32(x). overflow will be true. func (z *BigComplex) Int(bits int) (_ int64, truncation, overflow bool) { var integer *BigComplex integer, truncation = z.Integer() res := new(big.Int).Set(integer.Re.Num()) // Numerator must fit in bits - 1, with 1 bit left for sign if overflow = res.BitLen() > bits-1; overflow { var mask uint64 = ^uint64(0) >> uint(64-bits) res.And(res, new(big.Int).SetUint64(mask)) } return res.Int64(), truncation, overflow }
// trunc truncates a value to the range of the given type. func (t *_type) trunc(x *big.Int) *big.Int { r := new(big.Int) m := new(big.Int) m.Lsh(one, t.bits) m.Sub(m, one) r.And(x, m) if t.signed && r.Bit(int(t.bits)-1) == 1 { m.Neg(one) m.Lsh(m, t.bits) r.Or(r, m) } return r }
//intToBase64 makes string from int. func intToBase64(n *big.Int) string { var result string and := big.NewInt(0x3f) var tmp, nn big.Int nn.Set(n) for nn.Cmp(big.NewInt(0)) > 0 { bit := tmp.And(&nn, and).Uint64() result += string(base64en[bit]) nn.Rsh(&nn, 6) } return result + string(base64en[0]*byte(86-len(result))) }
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) } }
func binaryIntOp(x *big.Int, op token.Token, y *big.Int) interface{} { var z big.Int switch op { case token.ADD: return z.Add(x, y) case token.SUB: return z.Sub(x, y) case token.MUL: return z.Mul(x, y) case token.QUO: return z.Quo(x, y) case token.REM: return z.Rem(x, y) case token.AND: return z.And(x, y) case token.OR: return z.Or(x, y) case token.XOR: return z.Xor(x, y) case token.AND_NOT: return z.AndNot(x, y) case token.SHL: // The shift length must be uint, or untyped int and // convertible to uint. // TODO 32/64bit if y.BitLen() > 32 { panic("Excessive shift length") } return z.Lsh(x, uint(y.Int64())) case token.SHR: if y.BitLen() > 32 { panic("Excessive shift length") } return z.Rsh(x, uint(y.Int64())) case token.EQL: return x.Cmp(y) == 0 case token.NEQ: return x.Cmp(y) != 0 case token.LSS: return x.Cmp(y) < 0 case token.LEQ: return x.Cmp(y) <= 0 case token.GTR: return x.Cmp(y) > 0 case token.GEQ: return x.Cmp(y) >= 0 } panic("unreachable") }
func bigIntAnd(oldValues [][]byte, newValues [][]byte, w float64) (result [][]byte) { var sum *big.Int if oldValues != nil { sum = new(big.Int).SetBytes(oldValues[0]) for _, b := range newValues { sum.And(sum, new(big.Int).Mul(common.DecodeBigInt(b), big.NewInt(int64(w)))) } } else { sum = new(big.Int).Mul(new(big.Int).SetBytes(newValues[0]), big.NewInt(int64(w))) for _, b := range newValues[1:] { sum.And(sum, new(big.Int).Mul(common.DecodeBigInt(b), big.NewInt(int64(w)))) } } return [][]byte{sum.Bytes()} }
// z.Uint() returns a representation of z truncated to be a uint of // length bits. Valid values for bits are 0, 8, 16, 32, 64. The // returned result is otherwise undefined. If a truncation occurs, the // decimal part is dropped and the conversion continues as // usual. Return values truncation and overflow will be true if an // overflow occurs. The result is equivelant to a cast of the form // uint32(x). func (z *BigComplex) Uint(bits int) (_ uint64, truncation, overflow bool) { var integer *BigComplex integer, truncation = z.Integer() res := new(big.Int).Set(integer.Re.Num()) var mask uint64 = ^uint64(0) >> uint(64-bits) if overflow = res.BitLen() > bits; overflow { res.And(res, new(big.Int).SetUint64(mask)) res = new(big.Int).And(res, new(big.Int).SetUint64(mask)) } r := res.Uint64() if res.Sign() < 0 { overflow = true r = (^r + 1) & mask } return r, truncation, overflow }
func pad(v *big.Int) []byte { buf := make([]byte, SRP_KEY_SIZE) var m big.Int var n *big.Int n = big.NewInt(0) n = n.Add(n, v) for i, _ := range buf { buf[i] = byte(m.And(m.SetInt64(255), n).Int64()) n = n.Div(n, m.SetInt64(256)) } // reverse for i, j := 0, len(buf)-1; i < j; i, j = i+1, j-1 { buf[i], buf[j] = buf[j], buf[i] } return buf }
// Mod sets mod to n % Mexp and returns mod. It panics for exp == 0 || exp >= // math.MaxInt32 || n < 0. func Mod(mod, n *big.Int, exp uint32) *big.Int { if exp == 0 || exp >= math.MaxInt32 || n.Sign() < 0 { panic(0) } m := New(exp) mod.Set(n) var x big.Int for mod.BitLen() > int(exp) { x.Set(mod) x.Rsh(&x, uint(exp)) mod.And(mod, m) mod.Add(mod, &x) } if mod.BitLen() == int(exp) && mod.Cmp(m) == 0 { mod.SetInt64(0) } return mod }
// LastUsable returns the last address in a given network. func (ipv6 IPv6Addr) LastUsable() IPAddr { addr := new(big.Int) addr.Set(ipv6.Address) mask := new(big.Int) mask.Set(ipv6.Mask) negMask := new(big.Int) negMask.Xor(ipv6HostMask, mask) lastAddr := new(big.Int) lastAddr.And(addr, mask) lastAddr.Or(lastAddr, negMask) return IPv6Addr{ Address: IPv6Address(lastAddr), Mask: ipv6HostMask, } }
// Returns (degree, coefficients). // Coefficients holds the state of the variable bits (0, 1, ..., degree - 1). // Note that the k-th degree of a k degree polynomial is fixed (ie., 1) in // GF(2). // // The result is undefined if degree > 64. func (p *Polynomial) Uint64() (uint, uint64) { if p.degree > 64 { panic(fmt.Sprint("degree is too large", p.degree)) } tmp := new(big.Int).Set(&p.coeffs) if p.degree == 64 { // First, clear the MSB (bit), since we're interested in the // lower bits. tmp.SetBit(tmp, int(p.degree), 0) } mask := big.NewInt(int64(0xffffffff)) half := new(big.Int) lower := uint32(half.And(tmp, mask).Int64()) upper := uint32(half.Rsh(tmp, 32).And(half, mask).Int64()) v := uint64(lower) | (uint64(upper) << 32) return p.degree, v }
func main() { var n, e, d, bb, ptn, etn, dtn big.Int pt := "Rosetta Code" fmt.Println("Plain text: ", pt) // a key set big enough to hold 16 bytes of plain text in // a single block (to simplify the example) and also big enough // to demonstrate efficiency of modular exponentiation. n.SetString("9516311845790656153499716760847001433441357", 10) e.SetString("65537", 10) d.SetString("5617843187844953170308463622230283376298685", 10) // convert plain text to a number for _, b := range []byte(pt) { ptn.Or(ptn.Lsh(&ptn, 8), bb.SetInt64(int64(b))) } if ptn.Cmp(&n) >= 0 { fmt.Println("Plain text message too long") return } fmt.Println("Plain text as a number:", &ptn) // encode a single number etn.Exp(&ptn, &e, &n) fmt.Println("Encoded: ", &etn) // decode a single number dtn.Exp(&etn, &d, &n) fmt.Println("Decoded: ", &dtn) // convert number to text var db [16]byte dx := 16 bff := big.NewInt(0xff) for dtn.BitLen() > 0 { dx-- db[dx] = byte(bb.And(&dtn, bff).Int64()) dtn.Rsh(&dtn, 8) } fmt.Println("Decoded number as text:", string(db[dx:])) }
// z.Int() returns a representation of z, truncated to be an int of // length bits. Valid values for bits are 8, 16, 32, 64. Result is // otherwise undefined If a truncation occurs, the decimal part is // dropped and the conversion continues as usual. truncation will be // true If an overflow occurs, the result is equivelant to a cast of // the form int32(x). overflow will be true. func (z *BigComplex) Int(bits int) (_ int64, truncation, overflow bool) { var integer *BigComplex integer, truncation = z.Integer() res := new(big.Int).Set(integer.Re.Num()) // Numerator must fit in bits - 1, with 1 bit left for sign. // An exceptional case when only the signed bit is set. if overflow = res.BitLen() > bits-1; overflow { var mask uint64 = ^uint64(0) >> uint(64-bits) if res.BitLen() == bits && res.Sign() < 0 { // To detect the edge of minus 0b1000..., add one // to get 0b0ff... and recount the bits plus1 := new(big.Int).Add(res, big.NewInt(1)) if plus1.BitLen() < bits { return res.Int64(), truncation, false } } res.And(res, new(big.Int).SetUint64(mask)) } return res.Int64(), truncation, overflow }
func binaryIntOp(x *big.Int, op token.Token, y *big.Int) interface{} { var z big.Int switch op { case token.ADD: return z.Add(x, y) case token.SUB: return z.Sub(x, y) case token.MUL: return z.Mul(x, y) case token.QUO: return z.Quo(x, y) case token.REM: return z.Rem(x, y) case token.AND: return z.And(x, y) case token.OR: return z.Or(x, y) case token.XOR: return z.Xor(x, y) case token.AND_NOT: return z.AndNot(x, y) case token.SHL: panic("unimplemented") case token.SHR: panic("unimplemented") case token.EQL: return x.Cmp(y) == 0 case token.NEQ: return x.Cmp(y) != 0 case token.LSS: return x.Cmp(y) < 0 case token.LEQ: return x.Cmp(y) <= 0 case token.GTR: return x.Cmp(y) > 0 case token.GEQ: return x.Cmp(y) >= 0 } panic("unreachable") }
// bigIntExp is the "op" for exp on *big.Int. Different signature for Exp means we can't use *big.Exp directly. // Also we need a context (really a config); see the bigIntExpOp function below. // We know this is not 0**negative. func bigIntExp(c Context, i, j, k *big.Int) *big.Int { if j.Cmp(bigOne.Int) == 0 || j.Sign() == 0 { return i.Set(j) } // -1ⁿ is just parity. if j.Cmp(bigMinusOne.Int) == 0 { if k.And(k, bigOne.Int).Int64() == 0 { return i.Neg(j) } return i.Set(j) } // Large exponents can be very expensive. // First, it must fit in an int64. if k.BitLen() > 63 { Errorf("%s**%s: exponent too large", j, k) } exp := k.Int64() if exp < 0 { exp = -exp } mustFit(c.Config(), int64(j.BitLen())*exp) i.Exp(j, k, nil) return i }
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) vmlogger.Errorln("vm err", err) } }() } // 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 uint64 = 0 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 = stack.Peek().Uint64() + 32 case MLOAD: require(1) newMemSize = stack.Peek().Uint64() + 32 case MSTORE8: require(2) newMemSize = stack.Peek().Uint64() + 1 case RETURN: require(2) newMemSize = stack.Peek().Uint64() + stack.data[stack.Len()-2].Uint64() case SHA3: require(2) gas.Set(GasSha) newMemSize = stack.Peek().Uint64() + stack.data[stack.Len()-2].Uint64() case CALLDATACOPY: require(3) newMemSize = stack.Peek().Uint64() + stack.data[stack.Len()-3].Uint64() case CODECOPY: require(3) newMemSize = stack.Peek().Uint64() + stack.data[stack.Len()-3].Uint64() case CALL: require(7) gas.Set(GasCall) addStepGasUsage(stack.data[stack.Len()-1]) x := stack.data[stack.Len()-6].Uint64() + stack.data[stack.Len()-7].Uint64() y := stack.data[stack.Len()-4].Uint64() + stack.data[stack.Len()-5].Uint64() newMemSize = uint64(math.Max(float64(x), float64(y))) case CREATE: require(3) gas.Set(GasCreate) newMemSize = stack.data[stack.Len()-2].Uint64() + stack.data[stack.Len()-3].Uint64() } newMemSize = (newMemSize + 31) / 32 * 32 if newMemSize > uint64(mem.Len()) { m := GasMemory.Uint64() * (newMemSize - uint64(mem.Len())) / 32 addStepGasUsage(big.NewInt(int64(m))) } 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) 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.Sha3Bin(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: l := big.NewInt(int64(len(closure.Code))) stack.Push(l) self.Printf(" => %d", l) case CODECOPY: var ( size = int64(len(closure.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 } code := closure.Code[cOff : cOff+l] mem.Set(mOff, l, code) 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) stack.Dupn(n) self.Printf(" => [%d] 0x%x", n, stack.Peek().Bytes()) case SWAP1, SWAP2, SWAP3, SWAP4, SWAP5, SWAP6, SWAP7, SWAP8, SWAP9, SWAP10, SWAP11, SWAP12, SWAP13, SWAP14, SWAP15, SWAP16: n := int(op - SWAP1 + 1) 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) val, mStart := stack.Popn() //base.And(val, new(big.Int).SetInt64(0xff)) //mem.Set(mStart.Int64(), 32, ethutil.BigToBytes(base, 256)) mem.store[mStart.Int64()] = byte(val.Int64() & 0xff) self.Printf(" => 0x%x", 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 self.Printf(" ~> %v (t)", pc).Endl() continue } else { self.Printf(" (f)") } 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() // 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() msg := self.env.State().Manifest().AddMessage(ðstate.Message{ To: addr, From: closure.Address(), Origin: self.env.Origin(), Block: self.env.BlockHash(), Timestamp: self.env.Time(), Coinbase: self.env.Coinbase(), Number: self.env.BlockNumber(), Value: value, }) // Create a new contract contract := self.env.State().NewStateObject(addr) if contract.Balance.Cmp(value) >= 0 { closure.object.SubAmount(value) contract.AddAmount(value) // Set the init script initCode := mem.Get(offset.Int64(), size.Int64()) msg.Input = initCode // Transfer all remaining gas to the new // contract so it may run the init script gas := new(big.Int).Set(closure.Gas) closure.UseGas(closure.Gas) // Create the closure c := NewClosure(msg, closure, contract, initCode, gas, closure.Price) // Call the closure and set the return value as // main script. contract.Code, _, err = c.Call(self, nil) } else { err = fmt.Errorf("Insufficient funds to transfer value. Req %v, has %v", value, closure.object.Balance) } 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 { stack.Push(ethutil.BigD(addr)) msg.Output = contract.Code } self.Endl() // Debug hook if self.Dbg != nil { self.Dbg.SetCode(closure.Code) } case CALL: 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()) msg := self.env.State().Manifest().AddMessage(ðstate.Message{ To: addr.Bytes(), From: closure.Address(), Input: args, Origin: self.env.Origin(), Block: self.env.BlockHash(), Timestamp: self.env.Time(), Coinbase: self.env.Coinbase(), Number: self.env.BlockNumber(), Value: value, }) if closure.object.Balance.Cmp(value) < 0 { vmlogger.Debugf("Insufficient funds to transfer value. Req %v, has %v", value, closure.object.Balance) closure.ReturnGas(gas, nil) stack.Push(ethutil.BigFalse) } else { snapshot := self.env.State().Copy() stateObject := self.env.State().GetOrNewStateObject(addr.Bytes()) closure.object.SubAmount(value) stateObject.AddAmount(value) // Create a new callable closure c := NewClosure(msg, closure, stateObject, stateObject.Code, gas, closure.Price) // Executer the closure and get the return value (if any) ret, _, err := c.Call(self, args) if err != nil { stack.Push(ethutil.BigFalse) vmlogger.Debugf("Closure execution failed. %v\n", err) self.env.State().Set(snapshot) } else { stack.Push(ethutil.BigTrue) mem.Set(retOffset.Int64(), retSize.Int64(), ret) } msg.Output = 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) 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) Run(context *Context, callData []byte) (ret []byte, err error) { self.env.SetDepth(self.env.Depth() + 1) defer self.env.SetDepth(self.env.Depth() - 1) var ( caller = context.caller code = context.Code value = context.value price = context.Price ) self.Printf("(%d) (%x) %x (code=%d) gas: %v (d) %x", self.env.Depth(), caller.Address().Bytes()[:4], context.Address(), len(code), context.Gas, callData).Endl() // 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 self.After != nil { self.After(context, err) } if err != nil { self.Printf(" %v", err).Endl() // In case of a VM exception (known exceptions) all gas consumed (panics NOT included). context.UseGas(context.Gas) ret = context.Return(nil) } }() if context.CodeAddr != nil { if p := Precompiled[context.CodeAddr.Str()]; p != nil { return self.RunPrecompiled(p, callData, context) } } var ( op OpCode destinations = analyseJumpDests(context.Code) mem = NewMemory() stack = newStack() pc = new(big.Int) statedb = self.env.State() jump = func(from *big.Int, to *big.Int) error { nop := context.GetOp(to) if !destinations.Has(to) { return fmt.Errorf("invalid jump destination (%v) %v", nop, to) } self.Printf(" ~> %v", to) pc = to self.Endl() return nil } ) // Don't bother with the execution if there's no code. if len(code) == 0 { return context.Return(nil), nil } for { // The base for all big integer arithmetic base := new(big.Int) // Get the memory location of pc op = context.GetOp(pc) self.Printf("(pc) %-3d -o- %-14s (m) %-4d (s) %-4d ", pc, op.String(), mem.Len(), stack.len()) newMemSize, gas, err := self.calculateGasAndSize(context, caller, op, statedb, mem, stack) if err != nil { return nil, err } self.Printf("(g) %-3v (%v)", gas, context.Gas) if !context.UseGas(gas) { self.Endl() tmp := new(big.Int).Set(context.Gas) context.UseGas(context.Gas) return context.Return(nil), OOG(gas, tmp) } mem.Resize(newMemSize.Uint64()) switch op { // 0x20 range case ADD: x, y := stack.pop(), stack.pop() self.Printf(" %v + %v", y, x) base.Add(x, y) U256(base) self.Printf(" = %v", base) // pop result back on the stack stack.push(base) case SUB: x, y := stack.pop(), stack.pop() self.Printf(" %v - %v", y, x) base.Sub(x, y) U256(base) self.Printf(" = %v", base) // pop result back on the stack stack.push(base) case MUL: x, y := stack.pop(), stack.pop() self.Printf(" %v * %v", y, x) base.Mul(x, y) U256(base) self.Printf(" = %v", base) // pop result back on the stack stack.push(base) case DIV: x, y := stack.pop(), stack.pop() self.Printf(" %v / %v", x, y) if y.Cmp(common.Big0) != 0 { base.Div(x, y) } U256(base) self.Printf(" = %v", base) // pop result back on the stack stack.push(base) case SDIV: x, y := S256(stack.pop()), S256(stack.pop()) self.Printf(" %v / %v", x, y) 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) } self.Printf(" = %v", base) stack.push(base) case MOD: x, y := stack.pop(), stack.pop() self.Printf(" %v %% %v", x, y) if y.Cmp(common.Big0) == 0 { base.Set(common.Big0) } else { base.Mod(x, y) } U256(base) self.Printf(" = %v", base) stack.push(base) case SMOD: x, y := S256(stack.pop()), S256(stack.pop()) self.Printf(" %v %% %v", x, y) 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) } self.Printf(" = %v", base) stack.push(base) case EXP: x, y := stack.pop(), stack.pop() self.Printf(" %v ** %v", x, y) base.Exp(x, y, Pow256) U256(base) self.Printf(" = %v", 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) self.Printf(" = %v", num) stack.push(num) } case NOT: stack.push(U256(new(big.Int).Not(stack.pop()))) //base.Sub(Pow256, stack.pop()).Sub(base, common.Big1) //base = U256(base) //stack.push(base) case LT: x, y := stack.pop(), stack.pop() self.Printf(" %v < %v", x, y) // x < y if x.Cmp(y) < 0 { stack.push(common.BigTrue) } else { stack.push(common.BigFalse) } case GT: x, y := stack.pop(), stack.pop() self.Printf(" %v > %v", x, y) // 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()) self.Printf(" %v < %v", x, y) // 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()) self.Printf(" %v > %v", x, y) // x > y if x.Cmp(y) > 0 { stack.push(common.BigTrue) } else { stack.push(common.BigFalse) } case EQ: x, y := stack.pop(), stack.pop() self.Printf(" %v == %v", y, x) // 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) } // 0x10 range case AND: x, y := stack.pop(), stack.pop() self.Printf(" %v & %v", y, x) stack.push(base.And(x, y)) case OR: x, y := stack.pop(), stack.pop() self.Printf(" %v | %v", x, y) stack.push(base.Or(x, y)) case XOR: x, y := stack.pop(), stack.pop() self.Printf(" %v ^ %v", x, y) 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) } self.Printf(" => 0x%x", base.Bytes()) 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) } self.Printf(" %v + %v %% %v = %v", x, y, z, 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) } self.Printf(" %v + %v %% %v = %v", x, y, z, base) stack.push(base) // 0x20 range case SHA3: offset, size := stack.pop(), stack.pop() data := crypto.Sha3(mem.Get(offset.Int64(), size.Int64())) stack.push(common.BigD(data)) self.Printf(" => (%v) %x", size, data) // 0x30 range case ADDRESS: stack.push(common.Bytes2Big(context.Address().Bytes())) self.Printf(" => %x", context.Address()) case BALANCE: addr := common.BigToAddress(stack.pop()) balance := statedb.GetBalance(addr) stack.push(balance) self.Printf(" => %v (%x)", balance, addr) case ORIGIN: origin := self.env.Origin() stack.push(origin.Big()) self.Printf(" => %x", origin) case CALLER: caller := context.caller.Address() stack.push(common.Bytes2Big(caller.Bytes())) self.Printf(" => %x", caller) case CALLVALUE: stack.push(value) self.Printf(" => %v", value) case CALLDATALOAD: data := getData(callData, stack.pop(), common.Big32) self.Printf(" => 0x%x", data) stack.push(common.Bytes2Big(data)) case CALLDATASIZE: l := int64(len(callData)) stack.push(big.NewInt(l)) self.Printf(" => %d", l) case CALLDATACOPY: var ( mOff = stack.pop() cOff = stack.pop() l = stack.pop() ) data := getData(callData, cOff, l) mem.Set(mOff.Uint64(), l.Uint64(), data) self.Printf(" => [%v, %v, %v]", mOff, cOff, l) 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) self.Printf(" => %d", l) case CODECOPY, EXTCODECOPY: var code []byte if op == EXTCODECOPY { addr := common.BigToAddress(stack.pop()) code = statedb.GetCode(addr) } 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) self.Printf(" => [%v, %v, %v] %x", mOff, cOff, l, codeCopy) case GASPRICE: stack.push(context.Price) self.Printf(" => %x", context.Price) // 0x40 range 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) } self.Printf(" => 0x%x", stack.peek().Bytes()) case COINBASE: coinbase := self.env.Coinbase() stack.push(coinbase.Big()) 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(U256(number)) self.Printf(" => 0x%x", number.Bytes()) case DIFFICULTY: difficulty := self.env.Difficulty() stack.push(difficulty) self.Printf(" => 0x%x", difficulty.Bytes()) case GASLIMIT: self.Printf(" => %v", self.env.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 - PUSH1 + 1)) byts := getData(code, new(big.Int).Add(pc, big.NewInt(1)), a) // push value to stack stack.push(common.Bytes2Big(byts)) pc.Add(pc, a) self.Printf(" => 0x%x", byts) 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) self.Printf(" => [%d] 0x%x", n, stack.peek().Bytes()) 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) self.Printf(" => [%d]", 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()) //common.LeftPadBytes(stack.pop().Bytes(), 32) } data := mem.Get(mStart.Int64(), mSize.Int64()) log := state.NewLog(context.Address(), topics, data, self.env.BlockNumber().Uint64()) //log := &Log{context.Address(), topics, data, self.env.BlockNumber().Uint64()} self.env.AddLog(log) self.Printf(" => %v", log) case MLOAD: offset := stack.pop() val := common.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 // pop value of the stack mStart, val := stack.pop(), stack.pop() mem.Set(mStart.Uint64(), 32, common.BigToBytes(val, 256)) self.Printf(" => 0x%x", val) case MSTORE8: off, val := stack.pop().Int64(), stack.pop().Int64() mem.store[off] = byte(val & 0xff) self.Printf(" => [%v] 0x%x", off, mem.store[off]) case SLOAD: loc := common.BigToHash(stack.pop()) val := common.Bytes2Big(statedb.GetState(context.Address(), loc)) stack.push(val) self.Printf(" {0x%x : 0x%x}", loc, val.Bytes()) case SSTORE: loc := common.BigToHash(stack.pop()) val := stack.pop() statedb.SetState(context.Address(), loc, val) self.Printf(" {0x%x : 0x%x}", loc, val.Bytes()) case JUMP: if err := jump(pc, stack.pop()); err != nil { return nil, err } continue case JUMPI: pos, cond := stack.pop(), stack.pop() if cond.Cmp(common.BigTrue) >= 0 { if err := jump(pc, pos); err != nil { return nil, err } continue } self.Printf(" ~> false") case JUMPDEST: case PC: //stack.push(big.NewInt(int64(pc))) stack.push(pc) case MSIZE: stack.push(big.NewInt(int64(mem.Len()))) case GAS: stack.push(context.Gas) self.Printf(" => %x", context.Gas) // 0x60 range 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 ) self.Endl() context.UseGas(context.Gas) ret, suberr, ref := self.env.Create(context, input, gas, price, value) if suberr != nil { stack.push(common.BigFalse) self.Printf(" (*) 0x0 %v", suberr) } 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) self.Printf(" => %x", address).Endl() // 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) self.Printf("%v").Endl() } else { stack.push(common.BigTrue) mem.Set(retOffset.Uint64(), retSize.Uint64(), ret) } self.Printf("resume %x (%v)", context.Address(), context.Gas) case RETURN: offset, size := stack.pop(), stack.pop() ret := mem.Get(offset.Int64(), size.Int64()) self.Printf(" => [%v, %v] (%d) 0x%x", offset, size, len(ret), ret).Endl() return context.Return(ret), nil case SUICIDE: receiver := statedb.GetOrNewStateObject(common.BigToAddress(stack.pop())) balance := statedb.GetBalance(context.Address()) self.Printf(" => (%x) %v", receiver.Address().Bytes()[:4], balance) receiver.AddBalance(balance) statedb.Delete(context.Address()) fallthrough case STOP: // Stop the context self.Endl() return context.Return(nil), nil default: self.Printf("(pc) %-3v Invalid opcode %x\n", pc, op).Endl() return nil, fmt.Errorf("Invalid opcode %x", op) } pc.Add(pc, One) self.Endl() } }
// 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) { self.env.SetDepth(self.env.Depth() + 1) defer self.env.SetDepth(self.env.Depth() - 1) // 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 { // In case of a VM exception (known exceptions) all gas consumed (panics NOT included). context.UseGas(context.Gas) ret = context.Return(nil) } }() if context.CodeAddr != nil { if p := Precompiled[context.CodeAddr.Str()]; p != nil { return self.RunPrecompiled(p, input, context) } } var ( codehash = crypto.Sha3Hash(context.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 ForceJit { // Create and compile program program = NewProgram(context.Code) perr := CompileProgram(program) if perr == nil { return RunProgram(program, self.env, context, 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) go func() { err := CompileProgram(program) if err != nil { glog.V(logger.Info).Infoln("error compiling program", err) return } }() } } } 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 // 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 // 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()) return fmt.Errorf("invalid jump destination (%v) %v", nop, to) } pc = to.Uint64() return nil } newMemSize *big.Int cost *big.Int ) // 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) } }() // Don't bother with the execution if there's no code. if len(code) == 0 { return context.Return(nil), nil } 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) } */ // The base for all big integer arithmetic base := new(big.Int) // Get the memory location of pc op = context.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) 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) { 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)) 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) } 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) case SSTORE: loc := common.BigToHash(stack.pop()) val := stack.pop() statedb.SetState(context.Address(), loc, common.BigToHash(val)) case JUMP: if err := jump(pc, stack.pop()); err != nil { return nil, err } continue case JUMPI: pos, cond := stack.pop(), stack.pop() if cond.Cmp(common.BigTrue) >= 0 { if err := jump(pc, pos); err != nil { return nil, err } 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: return nil, fmt.Errorf("Invalid opcode %x", op) } pc++ } }
func U256(x *big.Int) *big.Int { x.And(x, tt256m1) return x }
// binaryOpConst returns the result of the constant evaluation x op y; // both operands must be of the same "kind" (boolean, numeric, or string). // If intDiv is true, division (op == token.QUO) is using integer division // (and the result is guaranteed to be integer) rather than floating-point // division. Division by zero leads to a run-time panic. // func binaryOpConst(x, y interface{}, op token.Token, intDiv bool) interface{} { x, y = matchConst(x, y) switch x := x.(type) { case bool: y := y.(bool) switch op { case token.LAND: return x && y case token.LOR: return x || y default: unreachable() } case int64: y := y.(int64) switch op { case token.ADD: // TODO(gri) can do better than this if is63bit(x) && is63bit(y) { return x + y } return normalizeIntConst(new(big.Int).Add(big.NewInt(x), big.NewInt(y))) case token.SUB: // TODO(gri) can do better than this if is63bit(x) && is63bit(y) { return x - y } return normalizeIntConst(new(big.Int).Sub(big.NewInt(x), big.NewInt(y))) case token.MUL: // TODO(gri) can do better than this if is32bit(x) && is32bit(y) { return x * y } return normalizeIntConst(new(big.Int).Mul(big.NewInt(x), big.NewInt(y))) case token.REM: return x % y case token.QUO: if intDiv { return x / y } return normalizeRatConst(new(big.Rat).SetFrac(big.NewInt(x), big.NewInt(y))) case token.AND: return x & y case token.OR: return x | y case token.XOR: return x ^ y case token.AND_NOT: return x &^ y default: unreachable() } case *big.Int: y := y.(*big.Int) var z big.Int switch op { case token.ADD: z.Add(x, y) case token.SUB: z.Sub(x, y) case token.MUL: z.Mul(x, y) case token.REM: z.Rem(x, y) case token.QUO: if intDiv { z.Quo(x, y) } else { return normalizeRatConst(new(big.Rat).SetFrac(x, y)) } case token.AND: z.And(x, y) case token.OR: z.Or(x, y) case token.XOR: z.Xor(x, y) case token.AND_NOT: z.AndNot(x, y) default: unreachable() } return normalizeIntConst(&z) case *big.Rat: y := y.(*big.Rat) var z big.Rat switch op { case token.ADD: z.Add(x, y) case token.SUB: z.Sub(x, y) case token.MUL: z.Mul(x, y) case token.QUO: z.Quo(x, y) default: unreachable() } return normalizeRatConst(&z) case complex: y := y.(complex) a, b := x.re, x.im c, d := y.re, y.im var re, im big.Rat switch op { case token.ADD: // (a+c) + i(b+d) re.Add(a, c) im.Add(b, d) case token.SUB: // (a-c) + i(b-d) re.Sub(a, c) im.Sub(b, d) case token.MUL: // (ac-bd) + i(bc+ad) var ac, bd, bc, ad big.Rat ac.Mul(a, c) bd.Mul(b, d) bc.Mul(b, c) ad.Mul(a, d) re.Sub(&ac, &bd) im.Add(&bc, &ad) case token.QUO: // (ac+bd)/s + i(bc-ad)/s, with s = cc + dd var ac, bd, bc, ad, s big.Rat ac.Mul(a, c) bd.Mul(b, d) bc.Mul(b, c) ad.Mul(a, d) s.Add(c.Mul(c, c), d.Mul(d, d)) re.Add(&ac, &bd) re.Quo(&re, &s) im.Sub(&bc, &ad) im.Quo(&im, &s) default: unreachable() } return normalizeComplexConst(complex{&re, &im}) case string: if op == token.ADD { return x + y.(string) } } unreachable() return nil }
func and(z *big.Int, x *big.Int, y *big.Int) *big.Int { return z.And(x, y) }
// Post-order traversal, equivalent to postfix notation. func Eval(node interface{}) (*big.Int, error) { switch nn := node.(type) { case *ast.BinaryExpr: z := new(big.Int) x, xerr := Eval(nn.X) if xerr != nil { return nil, xerr } y, yerr := Eval(nn.Y) if yerr != nil { return nil, yerr } switch nn.Op { case token.ADD: return z.Add(x, y), nil case token.SUB: return z.Sub(x, y), nil case token.MUL: return z.Mul(x, y), nil case token.QUO: if y.Sign() == 0 { // 0 denominator return nil, DivideByZero } return z.Quo(x, y), nil case token.REM: if y.Sign() == 0 { return nil, DivideByZero } return z.Rem(x, y), nil case token.AND: return z.And(x, y), nil case token.OR: return z.Or(x, y), nil case token.XOR: return z.Xor(x, y), nil case token.SHL: if y.Sign() < 0 { // negative shift return nil, NegativeShift } return z.Lsh(x, uint(y.Int64())), nil case token.SHR: if y.Sign() < 0 { return nil, NegativeShift } return z.Rsh(x, uint(y.Int64())), nil case token.AND_NOT: return z.AndNot(x, y), nil default: return nil, UnknownOpErr } case *ast.UnaryExpr: var z *big.Int var err error if z, err = Eval(nn.X); err != nil { return nil, err } switch nn.Op { case token.SUB: // -x return z.Neg(z), nil case token.XOR: // ^x return z.Not(z), nil case token.ADD: // +x (useless) return z, nil } case *ast.BasicLit: z := new(big.Int) switch nn.Kind { case token.INT: z.SetString(nn.Value, 0) return z, nil default: return nil, UnknownLitErr } case *ast.ParenExpr: z, err := Eval(nn.X) if err != nil { return nil, err } return z, nil case *ast.CallExpr: ident, ok := nn.Fun.(*ast.Ident) if !ok { return nil, UnknownTokenErr // quarter to four am; dunno correct error } var f Func f, ok = FuncMap[ident.Name] if !ok { return nil, UnknownFuncErr } var aerr error args := make([]*big.Int, len(nn.Args)) for i, a := range nn.Args { if args[i], aerr = Eval(a); aerr != nil { return nil, aerr } } x, xerr := f(args...) if xerr != nil { return nil, xerr } return x, nil } return nil, UnknownTokenErr }
// sanityCheckDomTree checks the correctness of the dominator tree // computed by the LT algorithm by comparing against the dominance // relation computed by a naive Kildall-style forward dataflow // analysis (Algorithm 10.16 from the "Dragon" book). // func sanityCheckDomTree(f *Function) { n := len(f.Blocks) // D[i] is the set of blocks that dominate f.Blocks[i], // represented as a bit-set of block indices. D := make([]big.Int, n) one := big.NewInt(1) // all is the set of all blocks; constant. var all big.Int all.Set(one).Lsh(&all, uint(n)).Sub(&all, one) // Initialization. for i, b := range f.Blocks { if i == 0 || b == f.Recover { // A root is dominated only by itself. D[i].SetBit(&D[0], 0, 1) } else { // All other blocks are (initially) dominated // by every block. D[i].Set(&all) } } // Iteration until fixed point. for changed := true; changed; { changed = false for i, b := range f.Blocks { if i == 0 || b == f.Recover { continue } // Compute intersection across predecessors. var x big.Int x.Set(&all) for _, pred := range b.Preds { x.And(&x, &D[pred.Index]) } x.SetBit(&x, i, 1) // a block always dominates itself. if D[i].Cmp(&x) != 0 { D[i].Set(&x) changed = true } } } // Check the entire relation. O(n^2). // The Recover block (if any) must be treated specially so we skip it. ok := true for i := 0; i < n; i++ { for j := 0; j < n; j++ { b, c := f.Blocks[i], f.Blocks[j] if c == f.Recover { continue } actual := b.Dominates(c) expected := D[j].Bit(i) == 1 if actual != expected { fmt.Fprintf(os.Stderr, "dominates(%s, %s)==%t, want %t\n", b, c, actual, expected) ok = false } } } preorder := f.DomPreorder() for _, b := range f.Blocks { if got := preorder[b.dom.pre]; got != b { fmt.Fprintf(os.Stderr, "preorder[%d]==%s, want %s\n", b.dom.pre, got, b) ok = false } } if !ok { panic("sanityCheckDomTree failed for " + f.String()) } }