move machine to module level

makes for shorter, more concise, access
also remove one more bug possibility
(reinitiation)

lib/arm/passes/call_implementation.rb

@@ -15,5 +15,5 @@ module Arm
       end
     end
   end
-  Virtual::Machine.instance.add_pass "Arm::CallImplementation"
+  Virtual.machine.add_pass "Arm::CallImplementation"
 end

lib/arm/passes/constant_implementation.rb

@@ -10,5 +10,5 @@ module Arm
       end
     end
   end
-  Virtual::Machine.instance.add_pass "Arm::ConstantImplementation"
+  Virtual.machine.add_pass "Arm::ConstantImplementation"
 end

lib/arm/passes/get_implementation.rb

@@ -9,5 +9,5 @@ module Arm
       end
     end
   end
-  Virtual::Machine.instance.add_pass "Arm::GetImplementation"
+  Virtual.machine.add_pass "Arm::GetImplementation"
 end

lib/arm/passes/main_implementation.rb

@@ -11,5 +11,5 @@ module Arm
       end
     end
   end
-  Virtual::Machine.instance.add_pass "Arm::MainImplementation"
+  Virtual.machine.add_pass "Arm::MainImplementation"
 end

lib/arm/passes/return_implementation.rb

@@ -9,5 +9,5 @@ module Arm
       end
     end
   end
-  Virtual::Machine.instance.add_pass "Arm::ReturnImplementation"
+  Virtual.machine.add_pass "Arm::ReturnImplementation"
 end

lib/arm/passes/save_implementation.rb

@@ -15,5 +15,5 @@ module Arm
       end
     end
   end
-  Virtual::Machine.instance.add_pass "Arm::SaveImplementation"
+  Virtual.machine.add_pass "Arm::SaveImplementation"
 end

lib/arm/passes/set_implementation.rb

@@ -9,5 +9,5 @@ module Arm
       end
     end
   end
-  Virtual::Machine.instance.add_pass "Arm::SetImplementation"
+  Virtual.machine.add_pass "Arm::SetImplementation"
 end

lib/arm/passes/transfer_implementation.rb

@@ -9,5 +9,5 @@ module Arm
       end
     end
   end
-  Virtual::Machine.instance.add_pass "Arm::TransferImplementation"
+  Virtual.machine.add_pass "Arm::TransferImplementation"
 end

lib/register/builtin/kernel.rb

@@ -8,7 +8,7 @@ module Builtin
         function = Virtual::CompiledMethodInfo.create_method(:Kernel,:__init__ , [])
 #        puts "INIT LAYOUT #{function.get_layout.get_layout}"
         function.info.return_type = Virtual::Integer
-        main = Virtual::Machine.instance.space.get_main
+        main = Virtual.machine.space.get_main
         me = Virtual::Self.new(Virtual::Reference)
         code = Virtual::Set.new(Virtual::Self.new(me.type), me)
         function.info.add_code(code)

lib/register/builtin/object.rb

@@ -23,7 +23,7 @@ module Builtin
         var_name = get_function.args.first
         return_to = get_function.return_type
 
-        index_function = ::Virtual::Machine.instance.space.get_class_by_name(:Object).resolve_method(:index_of)
+        index_function = ::Virtual.machine.space.get_class_by_name(:Object).resolve_method(:index_of)
 #        get_function.push( [me] )
 #        index = get_function.call( index_function )
 

lib/register/passes/call_implementation.rb

@@ -23,5 +23,5 @@ module Register
       end
     end
   end
-  Virtual::Machine.instance.add_pass "Register::CallImplementation"
+  Virtual.machine.add_pass "Register::CallImplementation"
 end

lib/register/passes/return_implementation.rb

@@ -18,5 +18,5 @@ module Register
       end
     end
   end
-  Virtual::Machine.instance.add_pass "Register::ReturnImplementation"
+  Virtual.machine.add_pass "Register::ReturnImplementation"
 end

lib/register/passes/set_implementation.rb

@@ -42,5 +42,5 @@ module Register
       end
     end
   end
-  Virtual::Machine.instance.add_pass "Register::SetImplementation"
+  Virtual.machine.add_pass "Register::SetImplementation"
 end

lib/virtual/compiled_method_info.rb

@@ -37,7 +37,7 @@ module Virtual
     def self.create_method( class_name , method_name , args)
       raise "uups #{class_name}.#{class_name.class}" unless class_name.is_a? Symbol
       raise "uups #{method_name}.#{method_name.class}" unless class_name.is_a? Symbol
-      clazz = Machine.instance.space.get_class_by_name class_name
+      clazz = Virtual.machine.space.get_class_by_name class_name
       raise "No such class #{class_name}" unless clazz
       method = clazz.create_instance_method( method_name , Virtual.new_list(args))
       method.info = CompiledMethodInfo.new

lib/virtual/machine.rb

@@ -39,6 +39,7 @@ module Virtual
       @parser  = Parser::Salama.new
       @passes = [ "Virtual::SendImplementation" ]
       @objects = []
+      @booted = false
     end
     attr_reader  :passes , :space , :class_mappings , :init , :objects
 
@@ -91,20 +92,17 @@ module Virtual
     end
 
     def self.boot
-      me = self.instance
+      me = Virtual.machine
       # boot is a verb here. this is a somewhat tricky process which is in it's own file, boot.rb
+      raise "already booted" if @booted
       me.boot_parfait!
       me
     end
-    def self.instance
-      @instance ||= Machine.new
-    end
 
     # for testing, make sure no old artefacts hang around
     #maybe should be moved to test dir
     def self.reboot
-      @instance = nil
-      self.boot
+      raise "redo"
     end
     def compile_main bytes
       syntax  = @parser.parse_with_debug(bytes)
@@ -112,6 +110,13 @@ module Virtual
       Compiler.compile( parts , @space.get_main )
     end
   end
+
+  def self.machine
+    unless defined?(@machine)
+      @machine = Machine.new
+    end
+    @machine
+  end
 end
 
 require_relative "boot"

lib/virtual/parfait_adapter.rb

@@ -9,7 +9,7 @@ module FakeMem
     super()
     @memory = [0,nil]
     @position = nil
-    if Virtual::Machine.instance.class_mappings
+    if Virtual.machine.class_mappings
       init_layout
     else
       #puts "No init for #{self.class}:#{self.object_id}"
@@ -17,7 +17,7 @@ module FakeMem
   end
   def init_layout
     vm_name = self.class.name.split("::").last.to_sym
-    clazz = Virtual::Machine.instance.class_mappings[vm_name]
+    clazz = Virtual.machine.class_mappings[vm_name]
     raise "Class not found #{vm_name}" unless clazz
     raise "Layout not set #{vm_name}" unless clazz.object_layout
     self.set_layout clazz.object_layout
@@ -25,7 +25,7 @@ module FakeMem
   #TODO, this is copied from module Positioned, maybe avoid duplication ?
   def position
     if @position.nil?
-      str = "IN machine #{Virtual::Machine.instance.objects.include?(self)}\n"
+      str = "IN machine #{Virtual.machine.objects.include?(self)}\n"
       raise str + "position not set for #{self.class} at #{mem_length} for #{self.inspect[0...100]}"
     end
     @position
@@ -71,7 +71,7 @@ class Symbol
     true
   end
   def get_layout
-    Virtual::Machine.instance.class_mappings[:Word].object_layout
+    Virtual.machine.class_mappings[:Word].object_layout
   end
   def mem_length
     to_s.length
@@ -87,7 +87,7 @@ class Symbol
     pos = cache_positions[self]
     if pos == nil
       str = "position accessed but not set, "
-      str += "Machine has object=#{Virtual::Machine.instance.objects.include?(self)} "
+      str += "Machine has object=#{Virtual.machine.objects.include?(self)} "
       raise str + " for Symbol:#{self}"
     end
     pos

lib/virtual/passes/collector.rb

@@ -9,7 +9,7 @@ module Virtual
 
     def keep object
       return if object.nil?
-      return unless Machine.instance.add_object object
+      return unless Virtual.machine.add_object object
       #puts "adding #{object.class}"
       unless object.has_layout?
         object.init_layout

lib/virtual/passes/enter_implementation.rb

@@ -13,5 +13,5 @@ module Virtual
       end
     end
   end
-  Virtual::Machine.instance.add_pass "Virtual::EnterImplementation"
+  Virtual.machine.add_pass "Virtual::EnterImplementation"
 end

lib/virtual/passes/frame_implementation.rb

@@ -48,5 +48,5 @@ module Virtual
       end
     end
   end
-  Virtual::Machine.instance.add_pass "Virtual::FrameImplementation"
+  Virtual.machine.add_pass "Virtual::FrameImplementation"
 end

lib/virtual/passes/get_implementation.rb

@@ -13,5 +13,5 @@ module Virtual
       end
     end
   end
-  Virtual::Machine.instance.add_pass "Virtual::GetImplementation"
+  Virtual.machine.add_pass "Virtual::GetImplementation"
 end

lib/virtual/passes/send_implementation.rb

@@ -30,7 +30,7 @@ module Virtual
           else
             # note: this is the current view: call internal send, even the method name says else
             # but send is "special" and accesses the internal method name and resolves.
-            kernel = Virtual::Machine.instance.space.get_class_by_name("Kernel")
+            kernel = Virtual.machine.space.get_class_by_name("Kernel")
             method = kernel.get_instance_method(:__send)
             new_codes << MethodCall.new( method )
             raise "unimplemented: \n#{code}"