Fixed issue with overflowing 256 bit integers

This commit is contained in:
obscuren 2014-08-08 12:04:18 +01:00
parent d6b0ab3028
commit 3fc24013ef

View File

@ -245,6 +245,8 @@ func (self *Vm) RunClosure(closure *Closure) (ret []byte, err error) {
base.Add(y, x)
ensure256(base)
self.Printf(" = %v", base)
// Pop result back on the stack
stack.Push(base)
@ -255,6 +257,8 @@ func (self *Vm) RunClosure(closure *Closure) (ret []byte, err error) {
base.Sub(y, x)
ensure256(base)
self.Printf(" = %v", base)
// Pop result back on the stack
stack.Push(base)
@ -265,6 +269,8 @@ func (self *Vm) RunClosure(closure *Closure) (ret []byte, err error) {
base.Mul(y, x)
ensure256(base)
self.Printf(" = %v", base)
// Pop result back on the stack
stack.Push(base)
@ -277,6 +283,8 @@ func (self *Vm) RunClosure(closure *Closure) (ret []byte, err error) {
base.Div(y, x)
}
ensure256(base)
self.Printf(" = %v", base)
// Pop result back on the stack
stack.Push(base)
@ -289,6 +297,8 @@ func (self *Vm) RunClosure(closure *Closure) (ret []byte, err error) {
base.Div(y, x)
}
ensure256(base)
self.Printf(" = %v", base)
// Pop result back on the stack
stack.Push(base)
@ -300,6 +310,8 @@ func (self *Vm) RunClosure(closure *Closure) (ret []byte, err error) {
base.Mod(y, x)
ensure256(base)
self.Printf(" = %v", base)
stack.Push(base)
case SMOD:
@ -310,6 +322,8 @@ func (self *Vm) RunClosure(closure *Closure) (ret []byte, err error) {
base.Mod(y, x)
ensure256(base)
self.Printf(" = %v", base)
stack.Push(base)
@ -321,6 +335,8 @@ func (self *Vm) RunClosure(closure *Closure) (ret []byte, err error) {
base.Exp(y, x, Pow256)
ensure256(base)
self.Printf(" = %v", base)
stack.Push(base)
@ -838,3 +854,18 @@ func (self *Vm) Endl() *Vm {
return self
}
func ensure256(x *big.Int) {
maxInt, _ := new(big.Int).SetString("115792089237316195423570985008687907853269984665640564039457584007913129639935", 0)
if x.Cmp(maxInt) >= 0 {
x.SetInt64(0)
return
}
// Could have done this with an OR, but big ints are costly.
if x.Cmp(new(big.Int)) < 0 {
x.SetInt64(0)
}
}