Return to_risc

remove the index from FunctionReturn, just jump to the register address

lib/mom/instruction/return_sequence.rb

@@ -19,8 +19,18 @@ module Mom
   # set of lower level instructions.
   #
   class ReturnSequence < Instruction
-    def to_risc(context)
-      Risc::Label.new(self,"ReturnSequence")
+    def to_risc(compiler)
+      return_move = SlotLoad.new( [:message ,:return_value] , [:message , :next_message, :return_value])
+      moves = return_move.to_risc(compiler)
+      caller_reg = compiler.use_reg(:int)
+      return_reg = compiler.use_reg(:int)
+      compiler.reset_regs
+      caller_index = Risc.resolve_to_index(:message , :caller)
+      return_index = Risc.resolve_to_index(:message , :return_address)
+      moves << Risc::SlotToReg.new(self, Risc.message_reg , caller_index , caller_reg)
+      moves << Risc::Transfer.new(self, caller_reg , Risc.message_reg)
+      moves << Risc::SlotToReg.new(self, Risc.message_reg, return_index , return_reg)
+      moves << Risc::FunctionReturn.new(self, return_reg)
     end
 
   end

lib/risc/instructions/function_return.rb

@@ -1,22 +1,21 @@
 module Risc
 
   # return from a function call
-  # register and index specify where the return address is stored
+  # register specifes where the return address is stored
 
   class FunctionReturn < Instruction
-    def initialize( source , register , index)
+    def initialize( source , register )
       super(source)
       @register = register
-      @index = index
     end
-    attr_reader :register , :index
+    attr_reader :register
 
     def to_s
-      "FunctionReturn: #{register} [#{index}]"
+      "FunctionReturn: #{register} "
     end
   end
 
-  def self.function_return( source , register , index)
-    FunctionReturn.new( source , register , index)
+  def self.function_return( source , register )
+    FunctionReturn.new( source , register )
   end
 end