1 files changed, 82 insertions, 0 deletions
diff --git a/core/vm/common.go b/core/vm/common.go
new file mode 100644
index 000000000..8d8f4253f
--- /dev/null
+++ b/core/vm/common.go
@@ -0,0 +1,82 @@
+package vm
+
+import (
+	"math"
+	"math/big"
+
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/logger"
+)
+
+var vmlogger = logger.NewLogger("VM")
+
+// Global Debug flag indicating Debug VM (full logging)
+var Debug bool
+
+type Type byte
+
+const (
+	StdVmTy Type = iota
+	JitVmTy
+	MaxVmTy
+
+	MaxCallDepth = 1025
+
+	LogTyPretty byte = 0x1
+	LogTyDiff   byte = 0x2
+)
+
+var (
+	Pow256 = common.BigPow(2, 256)
+
+	U256 = common.U256
+	S256 = common.S256
+
+	Zero = common.Big0
+
+	max = big.NewInt(math.MaxInt64)
+)
+
+func NewVm(env Environment) VirtualMachine {
+	switch env.VmType() {
+	case JitVmTy:
+		return NewJitVm(env)
+	default:
+		vmlogger.Infoln("unsupported vm type %d", env.VmType())
+		fallthrough
+	case StdVmTy:
+		return New(env)
+	}
+}
+
+func calcMemSize(off, l *big.Int) *big.Int {
+	if l.Cmp(common.Big0) == 0 {
+		return common.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
+}
+
+func getData(data []byte, start, size *big.Int) []byte {
+	dlen := big.NewInt(int64(len(data)))
+
+	s := common.BigMin(start, dlen)
+	e := common.BigMin(new(big.Int).Add(s, size), dlen)
+	return common.RightPadBytes(data[s.Uint64():e.Uint64()], int(size.Uint64()))
+}