diff --git a/test/vm/method_compiler/test_assignment.rb b/test/vm/method_compiler/test_assignment.rb
index d7635525..fb20df8a 100644
--- a/test/vm/method_compiler/test_assignment.rb
+++ b/test/vm/method_compiler/test_assignment.rb
@@ -7,7 +7,7 @@ module Register
     def test_assign_op
       Parfait.object_space.get_main.add_local(:r , :Integer)
 
-      @input    = s(:statements, s(:assignment, s(:name, :r), s(:operator_value, :+, s(:int, 10), s(:int, 1))))
+      @input    = s(:statements, s(:l_assignment, s(:name, :r), s(:operator_value, :+, s(:int, 10), s(:int, 1))))
 
       @expect = [Label, LoadConstant, LoadConstant, OperatorInstruction, SlotToReg, RegToSlot ,
                  LoadConstant, SlotToReg, RegToSlot, Label, FunctionReturn]
@@ -16,7 +16,7 @@ module Register
 
     def test_assign_local
       Parfait.object_space.get_main.add_local(:r , :Integer)
-      @input =s(:statements, s(:assignment, s(:name, :r), s(:int, 5)))
+      @input =s(:statements, s(:l_assignment, s(:name, :r), s(:int, 5)))
 
       @expect =  [Label, LoadConstant, SlotToReg, RegToSlot, LoadConstant, SlotToReg ,
                  RegToSlot, Label, FunctionReturn]
@@ -26,7 +26,7 @@ module Register
     def test_assign_local_assign
       Parfait.object_space.get_main.add_local(:r , :Integer)
 
-      @input = s(:statements, s(:assignment, s(:name, :r), s(:int, 5)))
+      @input = s(:statements, s(:l_assignment, s(:name, :r), s(:int, 5)))
 
       @expect = [Label, LoadConstant, SlotToReg, RegToSlot, LoadConstant, SlotToReg ,
                RegToSlot, Label, FunctionReturn]
@@ -35,7 +35,7 @@ module Register
 
     def test_assign_call
       Parfait.object_space.get_main.add_local(:r , :Integer)
-      @input = s(:statements, s(:assignment, s(:name, :r), s(:call, s(:name, :main), s(:arguments))))
+      @input = s(:statements, s(:l_assignment, s(:name, :r), s(:call, s(:name, :main), s(:arguments))))
       @expect = [Label, SlotToReg, SlotToReg, RegToSlot, LoadConstant, RegToSlot ,
                LoadConstant, SlotToReg, RegToSlot, LoadConstant, RegToSlot, RegisterTransfer ,
                FunctionCall, Label, RegisterTransfer, SlotToReg, SlotToReg, SlotToReg ,
@@ -45,7 +45,7 @@ module Register
 
     def test_named_list_get
       Parfait.object_space.get_main.add_local(:r , :Integer)
-      @input = s(:statements, s(:assignment, s(:name, :r), s(:int, 5)), s(:return, s(:name, :r)))
+      @input = s(:statements, s(:l_assignment, s(:name, :r), s(:int, 5)), s(:return, s(:name, :r)))
       @expect = [Label, LoadConstant, SlotToReg, RegToSlot, SlotToReg, SlotToReg ,
                  RegToSlot, LoadConstant, SlotToReg, RegToSlot, Label, FunctionReturn]
       was = check_return
@@ -56,7 +56,7 @@ module Register
 
     def test_assign_local_int
       Parfait.object_space.get_main.add_local(:r , :Integer)
-      @input = s(:statements, s(:assignment, s(:name, :r), s(:int, 5)) )
+      @input = s(:statements, s(:l_assignment, s(:name, :r), s(:int, 5)) )
       @expect =  [Label, LoadConstant, SlotToReg, RegToSlot, LoadConstant, SlotToReg ,
                  RegToSlot, Label, FunctionReturn]
       was = check_return
@@ -67,14 +67,14 @@ module Register
 
     def test_misassign_local
       Parfait.object_space.get_main.add_local(:r , :Integer)
-      @input = s(:statements, s(:assignment, s(:name, :r), s(:string, "5")) )
+      @input = s(:statements, s(:l_assignment, s(:name, :r), s(:string, "5")) )
       @expect =  [Label, LoadConstant, SlotToReg, RegToSlot, Label, FunctionReturn]
       assert_raises {check }
     end
 
     def test_assign_arg
       Parfait.object_space.get_main.add_argument(:blar , :Integer)
-      @input = s(:statements, s(:assignment, s(:name, :blar), s(:int, 5)))
+      @input = s(:statements, s(:a_assignment, s(:name, :blar), s(:int, 5)))
       @expect = [Label, LoadConstant, SlotToReg, RegToSlot, LoadConstant, SlotToReg ,
                  RegToSlot, Label, FunctionReturn]
       was = check_return
@@ -85,7 +85,7 @@ module Register
 
     def test_misassign_arg
       Parfait.object_space.get_main.add_argument(:blar , :Integer)
-      @input = s(:statements, s(:assignment, s(:name, :blar), s(:string, "5")))
+      @input = s(:statements, s(:a_assignment, s(:name, :blar), s(:string, "5")))
       @expect =  [Label, LoadConstant, SlotToReg, RegToSlot, Label, FunctionReturn]
       assert_raises {check }
     end
diff --git a/test/vm/method_compiler/test_call_site.rb b/test/vm/method_compiler/test_call_site.rb
index e0881465..38cee5d6 100644
--- a/test/vm/method_compiler/test_call_site.rb
+++ b/test/vm/method_compiler/test_call_site.rb
@@ -30,7 +30,7 @@ module Register
     def test_call_local_int
       Parfait.object_space.get_main.add_local(:testi , :Integer)
       clean_compile :Integer, :putint, {}, s(:statements, s(:return, s(:int, 1)))
-      @input = s(:statements, s(:assignment, s(:name, :testi), s(:int, 20)), s(:call, s(:name, :putint), s(:arguments), s(:receiver, s(:name, :testi))))
+      @input = s(:statements, s(:l_assignment, s(:name, :testi), s(:int, 20)), s(:call, s(:name, :putint), s(:arguments), s(:receiver, s(:name, :testi))))
 
       @expect = [Label, LoadConstant, SlotToReg, RegToSlot, SlotToReg, SlotToReg, SlotToReg ,
                  RegToSlot, LoadConstant, RegToSlot, LoadConstant, SlotToReg, RegToSlot, LoadConstant ,
diff --git a/test/vm/method_compiler/test_fields.rb b/test/vm/method_compiler/test_fields.rb
index 382c7475..afea1bd6 100644
--- a/test/vm/method_compiler/test_fields.rb
+++ b/test/vm/method_compiler/test_fields.rb
@@ -31,7 +31,7 @@ module Register
 
     def test_message_field
       Parfait.object_space.get_main.add_local(:name , :Word)
-      @input = s(:statements, s(:assignment, s(:name, :name), s(:field_access, s(:receiver, s(:name, :message)), s(:field, s(:name, :name)))), s(:return, s(:name, :name)))
+      @input = s(:statements, s(:l_assignment, s(:name, :name), s(:field_access, s(:receiver, s(:name, :message)), s(:field, s(:name, :name)))), s(:return, s(:name, :name)))
 
       @expect = [Label, RegisterTransfer, SlotToReg, SlotToReg, RegToSlot, SlotToReg ,
                  SlotToReg, RegToSlot, LoadConstant, SlotToReg, RegToSlot, Label ,
diff --git a/test/vm/method_compiler/test_return_statement.rb b/test/vm/method_compiler/test_return_statement.rb
index eb8ea88f..5d81a2af 100644
--- a/test/vm/method_compiler/test_return_statement.rb
+++ b/test/vm/method_compiler/test_return_statement.rb
@@ -21,7 +21,7 @@ module Register
 
     def test_return_local_assign
       Parfait.object_space.get_main.add_local(:runner , :Integer)
-      @input = s(:statements, s(:assignment, s(:name, :runner), s(:int, 5)), s(:return, s(:name, :runner)))
+      @input = s(:statements, s(:l_assignment, s(:name, :runner), s(:int, 5)), s(:return, s(:name, :runner)))
       @expect =  [Label, LoadConstant, SlotToReg, RegToSlot, SlotToReg, SlotToReg ,
                  RegToSlot, LoadConstant, SlotToReg, RegToSlot, Label, FunctionReturn]
       assert_nil msg = check_nil , msg
@@ -38,7 +38,7 @@ module Register
 
     def pest_return_space_length # need to add runtime first
       Parfait.object_space.get_main.add_local(:l , :Type)
-      @input = s(:statements, s(:assignment, s(:name, :l), s(:call, s(:name, :get_type), s(:arguments), s(:receiver, s(:name, :space)))), s(:return, s(:field_access, s(:receiver, s(:name, :self)), s(:field, s(:name, :runner)))))
+      @input = s(:statements, s(:l_assignment, s(:name, :l), s(:call, s(:name, :get_type), s(:arguments), s(:receiver, s(:name, :space)))), s(:return, s(:field_access, s(:receiver, s(:name, :self)), s(:field, s(:name, :runner)))))
       @expect =  [Label, SlotToReg,SlotToReg ,RegToSlot,Label,FunctionReturn]
       assert_nil msg = check_nil , msg
     end
diff --git a/test/vm/method_compiler/test_while_statement.rb b/test/vm/method_compiler/test_while_statement.rb
index 96ff2077..887e5ac0 100644
--- a/test/vm/method_compiler/test_while_statement.rb
+++ b/test/vm/method_compiler/test_while_statement.rb
@@ -17,7 +17,7 @@ module Register
     def test_while_assign
       Parfait.object_space.get_main.add_local(:n , :Integer)
 
-      @input    = s(:statements, s(:assignment, s(:name, :n), s(:int, 5)), s(:while_statement, :plus, s(:conditional, s(:name, :n)), s(:statements, s(:assignment, s(:name, :n), s(:operator_value, :-, s(:name, :n), s(:int, 1))))), s(:return, s(:name, :n)))
+      @input    = s(:statements, s(:l_assignment, s(:name, :n), s(:int, 5)), s(:while_statement, :plus, s(:conditional, s(:name, :n)), s(:statements, s(:l_assignment, s(:name, :n), s(:operator_value, :-, s(:name, :n), s(:int, 1))))), s(:return, s(:name, :n)))
 
       @expect = [Label, LoadConstant, SlotToReg, RegToSlot, Branch, Label ,
                  SlotToReg, SlotToReg, LoadConstant, OperatorInstruction, SlotToReg, RegToSlot ,
@@ -30,7 +30,7 @@ module Register
     def test_while_return
       Parfait.object_space.get_main.add_local(:n , :Integer)
 
-      @input    = s(:statements, s(:assignment, s(:name, :n), s(:int, 10)), s(:while_statement, :plus, s(:conditional, s(:operator_value, :-, s(:name, :n), s(:int, 5))), s(:statements, s(:assignment, s(:name, :n), s(:operator_value, :+, s(:name, :n), s(:int, 1))), s(:return, s(:name, :n)))))
+      @input    = s(:statements, s(:l_assignment, s(:name, :n), s(:int, 10)), s(:while_statement, :plus, s(:conditional, s(:operator_value, :-, s(:name, :n), s(:int, 5))), s(:statements, s(:l_assignment, s(:name, :n), s(:operator_value, :+, s(:name, :n), s(:int, 1))), s(:return, s(:name, :n)))))
 
       @expect = [Label, LoadConstant, SlotToReg, RegToSlot, Branch, Label ,
                  SlotToReg, SlotToReg, LoadConstant, OperatorInstruction, SlotToReg, RegToSlot ,
diff --git a/test/vm/test_to_code.rb b/test/vm/test_to_code.rb
index 860e69f2..e3860b52 100644
--- a/test/vm/test_to_code.rb
+++ b/test/vm/test_to_code.rb
@@ -16,9 +16,17 @@ class ToCodeTest < MiniTest::Test
     @statement = s(:while_statement, :false, s(:conditional,s(:int, 1)), s(:statements))
     check "WhileStatement"
   end
-  def test_assignment
-    @statement = s(:assignment, s(:name, :i), s(:int, 0))
-    check "Assignment"
+  def test_l_assignment
+    @statement = s(:l_assignment, s(:name, :i), s(:int, 0))
+    check "LocalAssignment"
+  end
+  def test_a_assignment
+    @statement = s(:a_assignment, s(:name, :i), s(:int, 0))
+    check "ArgAssignment"
+  end
+  def test_i_assignment
+    @statement = s(:i_assignment, s(:name, :i), s(:int, 0))
+    check "IvarAssignment"
   end
   def test_nil
     @statement = s(:nil)