remove class_eval on slots to map registers

Use their class names (or for now called object names)
these are the same that Register helper functions accept already anyway

lib/register/passes/set_implementation.rb

@@ -1,27 +1,4 @@
 
-#TODO: get rid of this. along the Register.* functions
-
-Virtual::MessageSlot.class_eval do
-  def reg
-    Register.message_reg
-  end
-end
-Virtual::FrameSlot.class_eval do
-  def reg
-    Register.frame_reg
-  end
-end
-Virtual::SelfSlot.class_eval do
-  def reg
-    Register.self_reg
-  end
-end
-Virtual::NewMessageSlot.class_eval do
-  def reg
-    Register.new_message_reg
-  end
-end
-
 module Register
   # This implements setting of the various slot variables the vm defines.
   # Basic mem moves, but have to shuffle the type nibbles (TODO!)
@@ -30,17 +7,15 @@ module Register
     def run block
       block.codes.dup.each do |code|
         next unless code.is_a? Virtual::Set
-        # resolve the register and offset that we need to move to
-        to = code.to.reg
         # need a temporay place because of indexed load/store
         tmp = Register.tmp_reg
         # for constants we have to "move" the constants value
         if( code.from.is_a?(Parfait::Value) or code.from.is_a?(Symbol))
           move1 = LoadConstant.new( code.from , tmp )
         else # while otherwise we "load"
-          move1 = GetSlot.new( code.from.reg , get_index(code.from) , tmp )
+          move1 = Register.get_slot( code.from.object_name , get_index(code.from) , tmp )
         end
-        move2 = SetSlot.new( tmp , to , get_index(code.to) )
+        move2 = Register.set_slot( tmp , code.to.object_name , get_index(code.to) )
         block.replace(code , [move1,move2] )
       end
     end

lib/virtual/slots/frame_slot.rb

@@ -7,6 +7,10 @@ module Virtual
     def initialize type = Unknown, value = nil
       super
     end
+
+    def object_name
+      return :frame
+    end
   end
 
 end

lib/virtual/slots/message_slot.rb

@@ -10,6 +10,9 @@ module Virtual
     def initialize type = Unknown , value = nil
       super(type , value )
     end
+    def object_name
+      :message
+    end
   end
 
   # named classes exist for slots that often accessed

lib/virtual/slots/next_message_slot.rb

@@ -10,6 +10,9 @@ module Virtual
     def initialize type = Unknown, value = nil
       super( type , value )
     end
+    def object_name
+      :new_message
+    end
   end
 
   # named classes exist for slots that often accessed

lib/virtual/slots/self_slot.rb

@@ -17,5 +17,8 @@ module Virtual
     def initialize type = Unknown, value = nil
       super
     end
+    def object_name
+      :self
+    end
   end
 end

lib/virtual/slots/slot.rb

@@ -18,6 +18,13 @@ module Virtual
 
   class Slot < Object
 
+    # the name of the object of a slot is a symbol that represents what the class name describes
+    # ie it is one of :message , :self , :frame , :new_message
+    # one of the objects the machine works on. 
+    def object_name
+      raise "abstract called #{self}"
+    end
+
     attr_accessor :type , :value
 
     private #abstract base class