simplify method entry exit codes

Basically just a label now
No more implicit returns (needs compiler tests)
Many return points is the new idea
Also setup is done before the enter by MessageSetup

lib/risc/assembler.rb

@@ -128,7 +128,7 @@ module Risc
         #puts "assemble #{method.source.instructions}"
         method.instructions.assemble_all( stream )
       rescue => e
-        log.debug "Assembly error #{method.name}\n#{Sof.write(method.instructions).to_s[0...2000]}"
+        log.debug "Assembly error #{method.name}\n#{method.to_rxf.to_s[0...2000]}"
         raise e
       end
       write_binary_method_to_stream( method, stream)

lib/risc/instruction.rb

@@ -86,7 +86,7 @@ require_relative "instructions/load_constant"
 require_relative "instructions/syscall"
 require_relative "instructions/function_call"
 require_relative "instructions/function_return"
-require_relative "instructions/register_transfer"
+require_relative "instructions/transfer"
 require_relative "instructions/label"
 require_relative "instructions/branch"
 require_relative "instructions/operator_instruction"

lib/risc/instructions/label.rb

@@ -45,13 +45,13 @@ module Risc
     end
 
     def assemble_all io , labels = []
-      return if labels.include?(self)
+      return if labels.include?(self) or self.next.nil?
       labels << self
       self.next.assemble_all(io,labels)
     end
 
     def total_byte_length labels = []
-      return 0 if labels.include?(self)
+      return 0 if labels.include?(self) or self.next.nil?
       labels << self
       ret = self.next.total_byte_length(labels)
       #puts "#{self.class.name} return #{ret}"
@@ -63,7 +63,7 @@ module Risc
       return position if labels.include?(self)
       labels << self
       super(position , labels)
-      self.next.set_position(position,labels)
+      self.next.set_position(position,labels) if self.next
     end
 
     # shame we need this, just for logging

lib/risc/method_compiler.rb

@@ -48,19 +48,7 @@ module Risc
       source = "_init_method"
       name = "#{method.for_type.name}.#{method.name}"
       @current = @method.set_instructions( Risc.label(source, name))
-
+      @current << Risc.label( source, "unreachable")
-      # add the type of the locals to the existing NamedList instance
-      frame_reg = use_reg(:Type , method.frame )
-      list_reg = use_reg(:NamedList )
-      add_load_constant("#{name} load frame type", method.frame , frame_reg)
-      add_slot_to_reg( "#{name} get frame from method" , :message , :frame , list_reg )
-      add_reg_to_slot( "#{name} store frame type in frame" , frame_reg , list_reg , 1  )
-
-      enter = @current # this is where method body goes
-      add_label( source, "return #{name}")
-      #load the return address into pc, affecting return. (other cpus have commands for this, but not arm)
-      add_function_return( source , Risc.message_reg , Risc.resolve_to_index(:message , :return_address) )
-      @current = enter
       self
     end
 

test/mom/helper.rb

@@ -11,10 +11,10 @@ module Risc
     end
 
     def preamble
-      [Label, LoadConstant, SlotToReg, RegToSlot ]
+      [Label ]
     end
     def postamble
-      [ Label, FunctionReturn]
+      [ Label]
     end
     # test hack to in place change object type
     def add_space_field(name,type)