diff options
| -rw-r--r-- | ethutil/big.go | 13 | ||||
| -rw-r--r-- | ethvm/vm.go | 53 |
2 files changed, 37 insertions, 29 deletions
diff --git a/ethutil/big.go b/ethutil/big.go index ec263b818..d8f54ad10 100644 --- a/ethutil/big.go +++ b/ethutil/big.go @@ -34,6 +34,19 @@ func BigD(data []byte) *big.Int { return n } +// To256 +// +// "cast" the big int to a 256 big int (i.e., limit to) +var tt256 = new(big.Int).Sub(new(big.Int).Lsh(big.NewInt(1), 256), big.NewInt(1)) + +func To256(x *big.Int) { + x.And(x, tt256) + + if x.Cmp(new(big.Int)) < 0 { + x.SetInt64(0) + } +} + // Big to bytes // // Returns the bytes of a big integer with the size specified by **base** diff --git a/ethvm/vm.go b/ethvm/vm.go index a8884f9fe..97adedbed 100644 --- a/ethvm/vm.go +++ b/ethvm/vm.go @@ -9,6 +9,9 @@ import ( "github.com/ethereum/eth-go/ethutil" ) +// Shortcut :-) +var To256 = ethutil.To256 + 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 @@ -262,7 +265,7 @@ func (self *Vm) RunClosure(closure *Closure) (ret []byte, err error) { base.Add(y, x) - ensure256(base) + To256(base) self.Printf(" = %v", base) // Pop result back on the stack @@ -274,7 +277,7 @@ func (self *Vm) RunClosure(closure *Closure) (ret []byte, err error) { base.Sub(y, x) - ensure256(base) + To256(base) self.Printf(" = %v", base) // Pop result back on the stack @@ -286,7 +289,7 @@ func (self *Vm) RunClosure(closure *Closure) (ret []byte, err error) { base.Mul(y, x) - ensure256(base) + To256(base) self.Printf(" = %v", base) // Pop result back on the stack @@ -300,7 +303,7 @@ func (self *Vm) RunClosure(closure *Closure) (ret []byte, err error) { base.Div(y, x) } - ensure256(base) + To256(base) self.Printf(" = %v", base) // Pop result back on the stack @@ -314,7 +317,7 @@ func (self *Vm) RunClosure(closure *Closure) (ret []byte, err error) { base.Div(y, x) } - ensure256(base) + To256(base) self.Printf(" = %v", base) // Pop result back on the stack @@ -327,7 +330,7 @@ func (self *Vm) RunClosure(closure *Closure) (ret []byte, err error) { base.Mod(y, x) - ensure256(base) + To256(base) self.Printf(" = %v", base) stack.Push(base) @@ -339,7 +342,7 @@ func (self *Vm) RunClosure(closure *Closure) (ret []byte, err error) { base.Mod(y, x) - ensure256(base) + To256(base) self.Printf(" = %v", base) stack.Push(base) @@ -352,7 +355,7 @@ func (self *Vm) RunClosure(closure *Closure) (ret []byte, err error) { base.Exp(y, x, Pow256) - ensure256(base) + To256(base) self.Printf(" = %v", base) @@ -465,7 +468,7 @@ func (self *Vm) RunClosure(closure *Closure) (ret []byte, err error) { base.Add(x, y) base.Mod(base, z) - ensure256(base) + To256(base) self.Printf(" = %v", base) @@ -480,7 +483,7 @@ func (self *Vm) RunClosure(closure *Closure) (ret []byte, err error) { base.Mul(x, y) base.Mod(base, z) - ensure256(base) + To256(base) self.Printf(" = %v", base) @@ -758,7 +761,7 @@ func (self *Vm) RunClosure(closure *Closure) (ret []byte, err error) { // Snapshot the current stack so we are able to // revert back to it later. - snapshot = self.env.State().Copy() + //snapshot = self.env.State().Copy() ) // Generate a new address @@ -778,7 +781,7 @@ func (self *Vm) RunClosure(closure *Closure) (ret []byte, err error) { stack.Push(ethutil.BigFalse) // Revert the state as it was before. - self.env.State().Set(snapshot) + //self.env.State().Set(snapshot) self.Printf("CREATE err %v", err) } else { @@ -809,7 +812,7 @@ func (self *Vm) RunClosure(closure *Closure) (ret []byte, err error) { // Get the arguments from the memory args := mem.Get(inOffset.Int64(), inSize.Int64()) - snapshot := self.env.State().Copy() + //snapshot := self.env.State().Copy() var executeAddr []byte if op == CALLCODE { @@ -823,7 +826,7 @@ func (self *Vm) RunClosure(closure *Closure) (ret []byte, err error) { if err != nil { stack.Push(ethutil.BigFalse) - self.env.State().Set(snapshot) + //self.env.State().Set(snapshot) } else { stack.Push(ethutil.BigTrue) @@ -905,21 +908,6 @@ func (self *Vm) Endl() *Vm { 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 @@ -937,6 +925,8 @@ func (self *Execution) Addr() []byte { } func (self *Execution) Exec(codeAddr []byte, caller ClosureRef) (ret []byte, err error) { + snapshot := self.vm.env.State().Copy() + msg := self.vm.env.State().Manifest().AddMessage(ðstate.Message{ To: self.address, From: caller.Address(), Input: self.input, @@ -957,6 +947,7 @@ func (self *Execution) Exec(codeAddr []byte, caller ClosureRef) (ret []byte, err 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) @@ -974,6 +965,10 @@ func (self *Execution) Exec(codeAddr []byte, caller ClosureRef) (ret []byte, err } } + if err != nil { + self.vm.env.State().Set(snapshot) + } + return } |