diff --git a/lib/register/assembler.rb b/lib/register/assembler.rb
index 7737584b..bcc8aa2e 100644
--- a/lib/register/assembler.rb
+++ b/lib/register/assembler.rb
@@ -51,12 +51,6 @@ module Register
         link_object code , at
       end
     end
-    def link_MethodEnter str , at    
-    end
-    def link_MethodReturn str , at    
-    end
-    def link_FunctionCall str , at    
-    end
     def link_String str , at    
     end
     def link_Symbol sym , at    
diff --git a/lib/register/enter_implementation.rb b/lib/register/enter_implementation.rb
new file mode 100644
index 00000000..f0663a02
--- /dev/null
+++ b/lib/register/enter_implementation.rb
@@ -0,0 +1,13 @@
+module Register
+
+  class EnterImplementation
+    def run block
+      block.codes.dup.each do |code|
+        next unless code.is_a? Virtual::MethodEnter
+        # save return register and create a new frame
+        block.replace(code , [] )
+      end
+    end
+  end
+  Virtual::BootSpace.space.add_pass_after EnterImplementation , CallImplementation
+end
diff --git a/lib/register/register_machine.rb b/lib/register/register_machine.rb
index f9c0c18b..ddb23206 100644
--- a/lib/register/register_machine.rb
+++ b/lib/register/register_machine.rb
@@ -149,5 +149,7 @@ require_relative "register_reference"
 require_relative "get_implementation"
 require_relative "set_implementation"
 require_relative "call_implementation"
+require_relative "enter_implementation"
+require_relative "return_implementation"
 require "arm/arm_machine"
 require_relative "assembler"
\ No newline at end of file
diff --git a/lib/register/return_implementation.rb b/lib/register/return_implementation.rb
new file mode 100644
index 00000000..16d3aad7
--- /dev/null
+++ b/lib/register/return_implementation.rb
@@ -0,0 +1,12 @@
+module Register
+  class ReturnImplementation
+    def run block
+      block.codes.dup.each do |code|
+        next unless code.is_a? Virtual::MethodReturn
+#        call = RegisterMachine.instance.call( code.method )
+        block.replace(code , [] )
+      end
+    end
+  end
+  Virtual::BootSpace.space.add_pass_after ReturnImplementation , CallImplementation 
+end