moved all compile to ast, vm does link and assemble. Getting there

lib/vm/block.rb

@@ -16,8 +16,7 @@ module Vm
 
   # See Value description on how to create code/instructions
   
-  # Blocks have a list of expressions, that they compile into a list of codes
-  # Codes then get assembled into bytes (after positioning)
+  # Codes then get assembled into bytes (after linking)
   
   class Block < Code
 
@@ -25,53 +24,35 @@ module Vm
       super()
       @name = name.to_sym
       @next = nil
-      @values = []
       @codes = []
     end
 
-    attr_reader :name  , :next , :codes , :values
+    attr_reader :name  , :next , :codes
 
-    def verify
-    end
-
-    def add_value v
-      @values << v
-    end
     def length
       @codes.inject(0) {| sum  , item | sum + item.length}
     end
+
     def add_code(kode)
-      kode.at(@position)
-      length = kode.length
-      @position += length
       @codes << kode
       self
     end
 
-    def compile context
-      @values.each do |value|
-        value.compile(context)
+    def link_at pos , context
+      @position = pos
+      @codes.each do |code|
+        code.link_at(pos , context)
+        pos += code.length
       end
+      pos
     end
+
     def assemble(io)
       @codes.each do |obj|
         obj.assemble io
       end
     end
 
-    # all machine methods produce blocks so it's a  unified interface. But often they are just linear 
-    # code after linear code, so then they can be joined. 
-    # The other block is useless after, all instructions move here  
-    def join other
-      raise "block is chained already, can't join #{inspect}" if @next
-      other.codes.each do |code|
-        add_code code
-      end
-      other.values.each do |value|
-        add_value value
-      end
-      self
-    end
     # set the next executed block after self.
     # why is this useful? if it's unconditional, why not merge them:
     #    So the second block can be used as a jump target. You standard loop needs a block to setup

lib/vm/code.rb

@@ -1,9 +1,7 @@
-require_relative "values"
-
 module Vm
   # Base class for anything that we can assemble
 
-  # Derived classes include instructions and data(strings)
+  # Derived classes include instructions and data(values)
   
   # The commonality abstracted here is the length and position
   # and the ability to assemble itself into the stream
@@ -11,7 +9,7 @@ module Vm
   # All code is position independant once assembled.
   # But for jumps and calls two passes are neccessary. 
   # The first setting the position, the second assembling
-  class Code < Value
+  class Code
     
     # set the position to zero, will have to reset later
     def initialize
@@ -29,7 +27,7 @@ module Vm
     
     # The containing class (assembler/function) call this to tell the instruction/data where it is in the
     # stream. During assembly the position is then used to calculate pc relative addresses.
-    def at address
+    def link_at address , context
       @address = address
     end
     

lib/vm/function.rb

@@ -28,18 +28,13 @@ module Vm
       @entry.length + @exit.length + super
     end
     
-    def compile context
+    def compiled context
       function = context.program.get_function(name)
       unless function
         function = Vm::Kernel.send(name)
         context.program.get_or_create_function( name , function , arity )
       end
     end
-    
-    def verify
-      @entry.verify
-      @exit.verify
-    end
 
     private 
     def add_arg value

lib/vm/program.rb

@@ -23,24 +23,25 @@ module Vm
     def initialize machine
       super("start")
       Machine.instance = eval("#{machine}::#{machine}Machine").new
-      
       @context = Context.new(self)
+      #global objects (data)
       @objects = []
+      # global functions
+      @functions = []
       @entry = Vm::Kernel::start
+      #main gets executed between entry and exit
+      @main = nil
       @exit = Vm::Kernel::exit
     end
-    attr_reader :context
+    attr_reader :context , :main , :functions
     
-    def functions
-      @values
-    end
     def add_object o
       return if @objects.include? o
       @objects << o # TODO check type , no basic values allowed (must be wrapped)
     end
     
     def get_function name
-      @values.detect{ |f| (f.name == name) && (f.class == Function) }
+      @functions.detect{ |f| (f.name == name) && (f.class == Function) }
     end
 
     # preferred way of creating new functions (also forward declarations, will flag unresolved later)
@@ -48,57 +49,33 @@ module Vm
       fun = get_function name
       unless fun
         fun = Function.new(name)
-        @values << fun
+        @functions << fun
       end
       fun
     end
     
-    def compile(context)
-      @values.each do |function|
-        function.compile(context)
-      end
-      @entry.compile(context)
-      super(context)
-      @exit.compile(context)
-      #string_table
-      @objects.each do |o|
-        o.compile(context)
-      end
-      fix_positions
-      fix_positions # second time for forward references
-    end
-    
-    def fix_positions
-      @position = 0
-      @entry.at( @position )
-      @position += @entry.length
-      @values.each do |function|
-        function.at(@position)
-        @position += function.length
+    def link_at( start , context)
+      @position = start
+      @entry.link_at( start , context )
+      start += @entry.length
+      @main.link_at( start , context )
+      start += @main.length
+      @functions.each do |function|
+        function.link_at(start , context)
+        start += function.length
       end
       @objects.each do |o|
-        o.at(@position)
-        @position += o.length
+        o.link_at(start , context)
+        start += o.length
       end
-      @exit.at( @position )
-      @position += @exit.length
+      @exit.link_at( start , context)
+      start += @exit.length
     end
     
-    def wrap_as_main block
-      # #blockify
-      unless block.is_a? Block      
-        raise "No block, start coding torsten"
-      end
-      add_value block
-      @entry.next block
-      block.next @exit
+    def main= code
+      @main = code
     end
-    def verify
-      @values.each do |funct|
-        funct.verify
-      end
-    end
-    
+        
     private 
     # the main function
     def create_main

lib/vm/values.rb

@@ -1,3 +1,5 @@
+require_relative "code"
+
 module Vm
   
   # Values represent the information as it is processed. Different subclasses for different types, 
@@ -16,29 +18,14 @@ module Vm
   # Word Values are what fits in a register. Derived classes
   # Float, Reference , Integer(s) must fit the same registers
   
-  class Value
-    def bit_size
-      8 * byte_size
-    end
-    
-    def byte_size
-      raise "abstract method called #{self.inspect}"
-    end
-    
-    # since we convert ast to values in conversion, value itself is responsible for compiling itself
-    # Compile must return a value, usually used in the next level up
-    def compile(context)
-      raise "abstract method called #{self.inspect}"
-    end
+  # just a base class for data. not sure how this will be usefull (may just have read too much llvm)
+  class Value < Code
   end
 
   class Word < Value
     def load reg
       Machine.instance.word_load self , reg
     end
-    def compile context
-      #nothing to do here
-    end
   end
   
   class Unsigned < Word
@@ -63,15 +50,9 @@ module Vm
     def initialize string
       @string = string
     end
-    def at pos
-      @pos = pos
-    end
     def length
       @string.length + 3
     end
-    def compile context
-      #nothing to do here
-    end
     attr_reader :string
   end
   
@@ -84,7 +65,7 @@ module Vm
     end
     attr_reader :object
     
-    def compile context
+    def compiled context
       if object.is_a? StringValue
         context.program.add_object object
       else