From 69781fb5059b02c448f49142fb2acd71105a1f1a Mon Sep 17 00:00:00 2001
From: Torsten Ruger <torsten@villataika.fi>
Date: Thu, 2 Jul 2015 13:48:32 +0300
Subject: [PATCH] remoe sys call message

and rely on linux to restore all registers
save message in r8
---
 lib/parfait/space.rb           |  1 -
 lib/register/builtin/kernel.rb | 21 +++++++--------------
 lib/virtual/boot.rb            |  2 +-
 3 files changed, 8 insertions(+), 16 deletions(-)

diff --git a/lib/parfait/space.rb b/lib/parfait/space.rb
index 0d000a26..8cef3e77 100644
--- a/lib/parfait/space.rb
+++ b/lib/parfait/space.rb
@@ -25,7 +25,6 @@ module Parfait
       super()
       Parfait::Space.set_object_space self
       @classes = Parfait::Dictionary.new_object
-      @syscall_message = nil  # a hack sto store the message during syscall
     end
     attr_reader :classes , :first_message
 
diff --git a/lib/register/builtin/kernel.rb b/lib/register/builtin/kernel.rb
index 266ca991..a64362db 100644
--- a/lib/register/builtin/kernel.rb
+++ b/lib/register/builtin/kernel.rb
@@ -43,28 +43,21 @@ module Register
           function.info.add_code Syscall.new( name )
           restore_message(function)
         end
+
         # save the current message, as the syscall destroys all context
         #
-        # currently HACKED into the space as a temporary varaible. As the space is a globally
-        # unique object we can retrieve it from there
-        # TODO : fix this to use global (later per thread) variable
+        # This relies on linux to save and restore all registers
+        # 
         def save_message(function)
-          space_tmp = Register.tmp_reg
-          ind = Register.resolve_index( :space , :syscall_message )
-          function.info.add_code LoadConstant.new( Parfait::Space.object_space , space_tmp)
-          function.info.add_code SetSlot.new( Register.message_reg , space_tmp , ind)
+          function.info.add_code RegisterTransfer.new( Register.message_reg , :r8 )
         end
 
         def restore_message(function)
-          # get the sys return out of the way
           return_tmp = Register.tmp_reg
+          # get the sys return out of the way
           function.info.add_code RegisterTransfer.new( Register.message_reg , return_tmp )
-          # load the space into the base register
-          function.info.add_code LoadConstant.new(Parfait::Space.object_space ,Register.message_reg)
-          # find the stored message
-          ind = Register.resolve_index( :space , :syscall_message )
-          # and load it into the base RegisterMachine
-          function.info.add_code Register.get_slot :message , ind , :message
+          # load the stored message into the base RegisterMachine
+          function.info.add_code RegisterTransfer.new( :r8 , Register.message_reg )
           # save the return value into the message
           function.info.add_code Register.set_slot( return_tmp , :message , :return_value )
           # and "unroll" self and frame
diff --git a/lib/virtual/boot.rb b/lib/virtual/boot.rb
index 4a04a894..2c7c775b 100644
--- a/lib/virtual/boot.rb
+++ b/lib/virtual/boot.rb
@@ -30,7 +30,7 @@ module Virtual
                                 :caller , :name ],
                   :MetaClass => [],
                   :BinaryCode => [],
-                  :Space => [:classes , :first_message , :syscall_message],
+                  :Space => [:classes , :first_message ],
                   :Frame => [:next_frame ],
                   :Layout => [:object_class] ,
                   :Class => [:object_layout ],