From eef6744827406ec3fc016b41db06c788c1c4efe4 Mon Sep 17 00:00:00 2001
From: Torsten Ruger <torsten@villataika.fi>
Date: Thu, 12 Jun 2014 08:34:46 +0300
Subject: [PATCH] fixes the if test (regs again)

---
 lib/arm/arm_machine.rb   | 21 ++++++++++++---------
 lib/ast/if_expression.rb |  4 ++--
 lib/core/kernel.rb       |  6 +-----
 3 files changed, 15 insertions(+), 16 deletions(-)

diff --git a/lib/arm/arm_machine.rb b/lib/arm/arm_machine.rb
index 06e96081..4f943045 100644
--- a/lib/arm/arm_machine.rb
+++ b/lib/arm/arm_machine.rb
@@ -93,11 +93,13 @@ module Arm
       entry
     end
 
-    # assumes string in r0 and r1 and moves them along for the syscall
-    def write_stdout block
+    # assumes string in standard receiver reg (r2) and moves them down for the syscall
+    def write_stdout function #, string
       # TODO save and restore r0
-      block.do_add  mov(  :r0 ,  1 ) # 1 == stdout
-      syscall( block , 4 )
+      function.mov(  :r0 ,  1 ) # 1 == stdout
+      function.mov( :r1 , :r2 )
+      function.mov( :r2 , :r3 )
+      syscall( function.insertion_point , 4 ) # 4 == write
     end
 
     
@@ -124,12 +126,13 @@ module Arm
     end
 
     def syscall block , num
-      #small todo, is this actually correct for all (that they return int)
-      sys_and_ret = Vm::Integer.new( Vm::RegisterMachine.instance.return_register )
-      block.do_add  mov(  sys_and_ret , num )
+      # This is very arm specific, syscall number is passed in r7, other arguments like a c call ie 0 and up
+      sys = Vm::Integer.new( Vm::RegisterUse.new(:r7) )
+      ret = Vm::Integer.new( Vm::RegisterUse.new(RETURN_REG) )
+      block.do_add  mov(  sys , num )
       block.do_add  swi(  0 )
-      #todo should write type into r0 according to syscall
-      sys_and_ret
+      #todo should write type into r1 according to syscall
+      ret
     end
 
   end
diff --git a/lib/ast/if_expression.rb b/lib/ast/if_expression.rb
index 0699a709..9a94ff1d 100644
--- a/lib/ast/if_expression.rb
+++ b/lib/ast/if_expression.rb
@@ -5,9 +5,9 @@ module Ast
       f = context.function
       # to execute the logic as the if states it, the blocks are the other way around
       # so we can the jump over the else if true ,and the else joins unconditionally after the true_block
-      false_block = f.new_block "if_false"
-      true_block = f.new_block "if_true"
       merge_block = f.new_block "if_merge"
+      true_block = f.new_block "if_true"
+      false_block = f.new_block "if_false"
 
       puts "compiling if condition #{cond}"
       cond_val = cond.compile(context)
diff --git a/lib/core/kernel.rb b/lib/core/kernel.rb
index 85787986..3efbfda8 100644
--- a/lib/core/kernel.rb
+++ b/lib/core/kernel.rb
@@ -5,13 +5,9 @@ module Core
     # We use this module syntax to avoid the (ugly) self (also eases searching).
     module ClassMethods
 
-      #TODO this is in the wrong place. It is a function that returns a function object
-      #   while all other methods add their code into some block. --> kernel
       def putstring context 
         function = Vm::Function.new(:putstring , Vm::Integer , [] )
-        block = function.body
-        # should be another level of indirection, ie write(io,str)
-        ret = Vm::RegisterMachine.instance.write_stdout(block)
+        ret = Vm::RegisterMachine.instance.write_stdout(function)
         function.set_return ret
         function
       end