diff --git a/build/soong/selinux.go b/build/soong/selinux.go
index 5fbe01eb..f811231 100644
--- a/build/soong/selinux.go
+++ b/build/soong/selinux.go
@@ -40,3 +40,13 @@
 
 	return android.PathForModuleOut(ctx, ctx.Config().DeviceName()).Join(ctx, paths...)
 }
+
+// flagsToM4Macros converts given map to a list of M4's -D parameters to guard te files and contexts
+// files.
+func flagsToM4Macros(flags map[string]string) []string {
+	flagMacros := []string{}
+	for _, flag := range android.SortedKeys(flags) {
+		flagMacros = append(flagMacros, "-D target_flag_"+flag+"="+flags[flag])
+	}
+	return flagMacros
+}