diff --git a/compiler/compiler/func.go b/compiler/compiler/func.go
index 42e6048..f8d78d9 100644
--- a/compiler/compiler/func.go
+++ b/compiler/compiler/func.go
@@ -123,18 +123,6 @@ func (c *Compiler) compileDefineFuncNode(v *parser.DefineFuncNode) value.Value {
 
 	funcRetType, treReturnTypes, llvmParams, treParams, isVariadicFunc, argumentReturnValuesCount := c.funcType(argTypes, retTypes)
 
-	isTxFFIFuncs := c.currentPackageName == "tx" &&
-		(compiledName == "is_owner_mode" ||
-			compiledName == "script_verify" ||
-			compiledName == "get_utxo_inputs" ||
-			compiledName == "get_utxo_outputs" ||
-			compiledName == "check_enhanced_owner_mode" ||
-			compiledName == "get_owner_mode" ||
-			compiledName == "get_flags" ||
-			compiledName == "get_err" ||
-			compiledName == "execute_scripts" ||
-			compiledName == "simple_udt" ||
-			compiledName == "parse_args")
 	var fn *ir.Func
 	var entry *ir.Block
 
@@ -153,7 +141,7 @@ func (c *Compiler) compileDefineFuncNode(v *parser.DefineFuncNode) value.Value {
 	} else {
 		fn = c.module.NewFunc(compiledName, funcRetType.LLVM(), llvmParams...)
 		// register ffi function definnition for tx package and os package
-		if isTxFFIFuncs {
+		if v.IsCFunc {
 			// do not generate block
 		} else {
 			entry = fn.NewBlock(name.Block())
@@ -170,7 +158,7 @@ func (c *Compiler) compileDefineFuncNode(v *parser.DefineFuncNode) value.Value {
 
 	// register ffi function definition for tx package
 	// without generate func body
-	if isTxFFIFuncs {
+	if v.IsCFunc {
 		val := value.Value{
 			Type:  typesFunc,
 			Value: fn,
diff --git a/pkg/cell/cell.cell b/pkg/cell/cell.cell
index e6b1481..08d31cb 100644
--- a/pkg/cell/cell.cell
+++ b/pkg/cell/cell.cell
@@ -20,7 +20,7 @@ type Script table {
 type XudtArgs table {
 	owner_mode	bool
 	err			int64
-	flags 		uint32
+	flags 		int64
 	script  	[32768]byte
 	codeBuf_padding [4076]byte
 	codeBuf 	[1843200]byte
diff --git a/pkg/tx/tx.cell b/pkg/tx/tx.cell
index 74e71dd..b1f63d7 100644
--- a/pkg/tx/tx.cell
+++ b/pkg/tx/tx.cell
@@ -12,82 +12,39 @@ const (
 	SUCCESS = iota
 )
 
-function script_verify() bool {
-	return true
-}
+cfunction script_verify() bool
+cfunction is_owner_mode() bool
+cfunction get_utxo_inputs() []cell.Cell
+cfunction get_utxo_outputs() []cell.Cell
+
 function scriptVerify() bool {
 	return script_verify()
 }
-
-function is_owner_mode() bool {
-	return true
-}
 function isOwnerMode() bool {
 	return is_owner_mode()
 }
-
-function get_utxo_inputs() []cell.Cell {
-	return []cell.Cell{}
-}
 function inputs() []cell.Cell {
 	return get_utxo_inputs()
 }
-
-function get_utxo_outputs() []cell.Cell {
-	return []cell.Cell{}
-}
 function outputs() []cell.Cell {
 	return get_utxo_outputs()
 }
 
 // xudt related API and ffi functions
-function parse_args() *cell.XudtArgs {
-	return 0
-}
+cfunction parse_args() *cell.XudtArgs
+cfunction check_enhanced_owner_mode(args *cell.XudtArgs) bool
+cfunction simple_udt(owner_mode bool) int64
+cfunction execute_scripts(args *cell.XudtArgs) bool
+
 function xudtArgs() *cell.XudtArgs {
 	return parse_args()
 }
-
-function check_enhanced_owner_mode(args *cell.XudtArgs) bool {
-	return false
-}
 function checkEnhancedOwnerMode(args *cell.XudtArgs) bool {
 	return check_enhanced_owner_mode(args)
 }
-
-function simple_udt(owner_mode bool) int64 {
-	return 0
-}
 function sudt(owner_mode bool) int64 {
 	return simple_udt(owner_mode)
 }
-
-function get_flags(args uintptr) int64 {
-	return 0
-}
-function getFlags(args uintptr) int64 {
-	return get_flags(args)
-}
-
-function get_err(args uintptr) int64 {
-	return 0
-}
-function getErr(args uintptr) int64 {
-	return get_err(args)
-}
-
-function get_owner_mode(args uintptr) int64 {
-	return 0
-}
-function getOwnerMode(args *cell.XudtArgs) int64 {
-	return get_owner_mode(args)
-}
-
-function execute_scripts(args *cell.XudtArgs) bool {
-	return false
-}
 function executeScripts(args *cell.XudtArgs) bool {
 	return execute_scripts(args)
 }
-
-