diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..600d2d3
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1 @@
+.vscode
\ No newline at end of file
diff --git a/arm/neon/functions.go b/arm/neon/functions.go
old mode 100644
new mode 100755
index 56dd53b..9ec5136
--- a/arm/neon/functions.go
+++ b/arm/neon/functions.go
@@ -9048,4 +9048,3 @@ func VabalHighS32(v0 Int64X2, v1 Int32X4, v2 Int32X4) Int64X2 {
 func VabalHighS16(v0 Int32X4, v1 Int16X8, v2 Int16X8) Int32X4 {
 	return Int32X4(C.vabal_high_s16(C.int32x4_t(v0), C.int16x8_t(v1), C.int16x8_t(v2)))
 }
-
diff --git a/arm/neon/generate.go b/arm/neon/generate.go
new file mode 100644
index 0000000..7f562bd
--- /dev/null
+++ b/arm/neon/generate.go
@@ -0,0 +1,4 @@
+package neon
+
+//go:generate go run ../../cmd/generator -package=neon -types -o types.go
+//go:generate go run ../../cmd/generator -package=neon -funcs -o functions.go
diff --git a/arm/neon/types.go b/arm/neon/types.go
old mode 100644
new mode 100755
diff --git a/cmd/generator/main.go b/cmd/generator/main.go
index 68844d8..e7fa2e7 100644
--- a/cmd/generator/main.go
+++ b/cmd/generator/main.go
@@ -2,6 +2,7 @@ package main
 
 import (
 	"bytes"
+	"io"
 	"log"
 	"os"
 	"os/exec"
@@ -14,6 +15,11 @@ func main() {
 	app := cli.App{
 		Name: "go-simd-generator",
 		Flags: []cli.Flag{
+			&cli.StringFlag{
+				Name:     "package",
+				Usage:    "Go package name",
+				Required: true,
+			},
 			&cli.BoolFlag{
 				Name:  "types",
 				Usage: "skip types",
@@ -22,6 +28,11 @@ func main() {
 				Name:  "funcs",
 				Usage: "skip functions",
 			},
+			&cli.StringFlag{
+				Name:    "output",
+				Aliases: []string{"o"},
+				Usage:   "output file",
+			},
 		},
 		Action: action,
 	}
@@ -40,7 +51,7 @@ func action(cli *cli.Context) error {
 		return err
 	}
 	pkg := &scanner.Package{
-		Name: "neon",
+		Name: cli.String("package"),
 		C: []string{
 			"#include <arm_neon.h>",
 		},
@@ -53,7 +64,18 @@ func action(cli *cli.Context) error {
 	if !cli.Bool("funcs") {
 		pkg.Functions = nil
 	}
-	pkg.WriteTo(os.Stdout)
+	var w io.Writer
+	if output := cli.String("output"); len(output) > 0 {
+		f, err := os.OpenFile(output, os.O_CREATE|os.O_WRONLY|os.O_TRUNC, os.ModePerm)
+		if err != nil {
+			return err
+		}
+		defer f.Close()
+		w = f
+	} else {
+		w = os.Stdout
+	}
+	pkg.WriteTo(w)
 	return nil
 }
 
diff --git a/scanner/function.go b/scanner/function.go
index a08cbb7..ddffb8d 100644
--- a/scanner/function.go
+++ b/scanner/function.go
@@ -20,7 +20,8 @@ type Arg struct {
 
 const funcTemplate = `func %s(%s) %s {
 	return %s(C.%s(%s))
-}`
+}
+`
 
 func (f *Function) String() string {
 	return fmt.Sprintf(
diff --git a/scanner/package.go b/scanner/package.go
index 8ea8206..3e9f106 100644
--- a/scanner/package.go
+++ b/scanner/package.go
@@ -14,11 +14,11 @@ type Package struct {
 }
 
 func (pkg *Package) WriteTo(w io.Writer) error {
-	if _, err := fmt.Fprintf(w, "package %s\n\n", pkg.Name); err != nil {
+	if _, err := fmt.Fprintf(w, "package %s\n", pkg.Name); err != nil {
 		return err
 	}
 	if len(pkg.C) > 0 {
-		if _, err := fmt.Fprintf(w, "/*\n%s\n*/\nimport \"C\"\n\n", strings.Join(pkg.C, "\n")); err != nil {
+		if _, err := fmt.Fprintf(w, "\n/*\n%s\n*/\nimport \"C\"\n", strings.Join(pkg.C, "\n")); err != nil {
 			return err
 		}
 	}
@@ -26,7 +26,7 @@ func (pkg *Package) WriteTo(w io.Writer) error {
 		if strings.Contains(string(t), "float16") {
 			continue
 		}
-		if _, err := fmt.Fprintf(w, "type %s C.%s\n\n", t.GoString(), t); err != nil {
+		if _, err := fmt.Fprintf(w, "\ntype %s C.%s\n", t.GoString(), t); err != nil {
 			return err
 		}
 	}
@@ -40,7 +40,7 @@ funcs:
 				continue funcs
 			}
 		}
-		if _, err := fmt.Fprintf(w, "%s\n\n", fn.String()); err != nil {
+		if _, err := fmt.Fprintf(w, "\n%s", fn.String()); err != nil {
 			return err
 		}
 	}