diff --git a/lib/risc/machine.rb b/lib/risc/machine.rb
index 1aa05b0f..f6d70f33 100644
--- a/lib/risc/machine.rb
+++ b/lib/risc/machine.rb
@@ -114,7 +114,7 @@ module Risc
         before = at
         nekst = method.binary
         while(nekst)
-          Position.set_position(nekst , at)
+          Position.set_position(nekst , at , method)
           at += nekst.padded_length
           nekst = nekst.next
         end
diff --git a/lib/risc/position.rb b/lib/risc/position.rb
index 31bbbcc1..b0f7faf7 100644
--- a/lib/risc/position.rb
+++ b/lib/risc/position.rb
@@ -35,7 +35,13 @@ module Risc
     def to_s
       "0x#{@at.to_s(16)}"
     end
-
+    def reset_to(pos)
+      if((at - pos).abs > 1000)
+        raise "position set too far off #{pos}!=#{at} for #{object}:#{object.class}"
+      end
+      @at = pos
+      self
+    end
     def self.positions
       @positions
     end
@@ -51,15 +57,40 @@ module Risc
       pos
     end
 
-    def self.set_position( object , pos )
+    def self.set_position( object , pos , extra = nil)
       # resetting of position used to be error, but since relink and dynamic instruction size it is ok.
       # in measures (of 32)
       #puts "Setting #{pos} for #{self.class}"
       old = Position.positions[object]
-      if old != nil and ((old - pos).abs > 1000)
-        raise "position set too far off #{pos}!=#{old} for #{object}:#{object.class}"
+      return old.reset_to(pos) if old != nil
+      self.positions[object] = for_at( object , pos , extra)
+    end
+
+    def self.for_at(object , at , extra)
+      case object
+      when Parfait::BinaryCode
+        BPosition.new(object,at , extra)
+      when Arm::Instruction , Risc::Label
+        IPosition.new(object,at)
+      else
+        Position.new(at)
       end
-      self.positions[object] = Position.new( pos )
+    end
+  end
+  # handle event propagation
+  class IPosition < Position
+    attr_reader :instruction
+    def initialize(instruction, pos)
+      super(pos)
+      @instruction = instruction
+    end
+  end
+  class BPosition < Position
+    attr_reader :code , :method
+    def initialize(code, pos , method)
+      super(pos)
+      @code = code
+      @method = method
     end
   end
 end
diff --git a/test/risc/test_position.rb b/test/risc/test_position.rb
index 0d5068bc..763aefaa 100644
--- a/test/risc/test_position.rb
+++ b/test/risc/test_position.rb
@@ -25,6 +25,10 @@ module Risc
       pos = Position.set_position(self , 5)
       assert_equal 5 , pos.at
     end
+    def test_set_instr
+      pos = Position.set_position( Risc::Label.new("hi","ho") , 0)
+      assert_equal IPosition , pos.class
+    end
     def tet_tos
       assert_equal "0x10" , Position.set_position(self).to_s
     end