fixing address resolution cleans up hello world

lib/asm/arm/instruction.rb

@@ -31,7 +31,7 @@ module Asm
         @opcode = opcode.downcase.to_sym
         @args = args
       end
-      attr_reader :opcode, :args
+      attr_reader :opcode, :args , :position
 
       def affect_status
         @s
@@ -55,7 +55,7 @@ module Asm
           builder.cond = COND_CODES[@cond]
           builder.rd = reg_ref(args[0])
           builder.rn = reg_ref(args[1])
-          builder.build_operand args[2]
+          builder.build_operand args[2] , self.position
           builder.assemble io, as
         when :cmn, :cmp, :teq, :tst
           builder = NormalBuilder.new(OPC_DATA_PROCESSING, OPCODES[opcode], 1)

lib/asm/arm/normal_builder.rb

@@ -43,7 +43,14 @@ module Asm
       end
 
       # Build representation for source value
-      def build_operand(arg)
+      def build_operand(arg , position = 0) 
+        #position only needed for calculating relative addresses to data objects
+        #there is a design stink here which makes my head ache. But shanti shanti
+        if arg.is_a?(Asm::DataObject)
+          # do pc relative addressing with the difference to the instuction
+          # 8 is for the funny pipeline adjustment (ie oc pointing to fetch and not execute)
+          arg = Asm::NumLiteralNode.new( arg.position - position - 8 )
+        end
         if (arg.is_a?(Asm::NumLiteralNode))
           if (arg.value.fits_u8?)
             # no shifting needed
@@ -82,10 +89,7 @@ module Asm
           end
       
           @operand = rm_ref | (shift_op << 4) | (shift_imm << 4+3)
-        elsif arg.is_a?(Asm::DataObject)
-          # do pc relative addressing with the difference to the instuction
         else
-          puts "#{self.inspect}"
           raise Asm::AssemblyError.new(Asm::ERRSTR_INVALID_ARG + " " + arg.inspect, arg)
         end
       end

lib/asm/data_object.rb

@@ -4,6 +4,10 @@ module Asm
       @data = data
     end
     
+    def position
+      throw "Not set" unless @address
+      @address 
+    end
     def at address
       @address = address
     end