remove MethodEnter Instructions

only resolved to SaveReturn anyway
also Halt instruction wasn’t used, gone
passes changed to start at register

lib/virtual.rb

@@ -11,7 +11,6 @@ require "virtual/method_source"
 # the passes _are_ order dependant
 require "virtual/passes/minimizer"
 require "virtual/passes/collector"
-require "virtual/passes/enter_implementation"
 
 
 class Fixnum

lib/virtual/instruction.rb

@@ -13,6 +13,4 @@ module Virtual
 
 end
 
-require_relative "instructions/halt"
 require_relative "instructions/method_call"
-require_relative "instructions/method_enter"

lib/virtual/instructions/halt.rb

@@ -1,12 +0,0 @@
-module Virtual
-
-
-  # the first instruction we need is to stop. Off course in a real machine this would be a syscall,
-  # but that is just  an implementation (in a programm it would be a function).
-  # But in a virtual machine, not only do we need this instruction,
-  # it is indeed the first instruction as just this instruction is the smallest possible programm
-  # for the machine.
-  # As such it is the next instruction for any first instruction that we generate.
-  class Halt < Instruction
-  end
-end

lib/virtual/instructions/method_enter.rb

@@ -1,12 +0,0 @@
-module Virtual
-
-  # following classes are stubs. currently in brainstorming mode, so anything may change anytime
-  class MethodEnter < Instruction
-    def initialize method
-      @method = method
-    end
-
-    attr_reader :method
-  end
-
-end

lib/virtual/machine.rb

@@ -36,8 +36,7 @@ module Virtual
 
   class Machine
 
-    FIRST_PASS = "Virtual::EnterImplementation"
-    LAST_PASS = "Virtual::SetOptimisation"
+    FIRST_PASS = "Register::CallImplementation"
 
     def initialize
       @parser  = Parser::Salama.new

lib/virtual/method_source.rb

@@ -56,7 +56,8 @@ module Virtual
 
     def init method , return_type = nil
       # first block we have to create with .new , as new_block assumes a current
-      enter = Block.new( "enter"  , method ).add_code(MethodEnter.new( method ))
+      enter = Block.new( "enter"  , method )
+      enter.add_code Register.save_return(self, :message , :return_address)
       set_return_type( return_type )
       @blocks = [enter]
       @current = enter

lib/virtual/passes/enter_implementation.rb

@@ -1,15 +0,0 @@
-module Virtual
-
-  class EnterImplementation
-    def run block
-      block.codes.dup.each do |code|
-        next unless code.is_a? Virtual::MethodEnter
-        new_codes = []
-        # save return register to the message at instance return_address
-        new_codes << Register.save_return(code, :message , :return_address)
-        block.replace(code , new_codes )
-      end
-    end
-  end
-  Virtual.machine.add_pass "Virtual::EnterImplementation"
-end