From 990b4726ba9a3fc5fd6ead935660f31af66f3251 Mon Sep 17 00:00:00 2001
From: Torsten Ruger <torsten@villataika.fi>
Date: Fri, 2 May 2014 08:02:25 +0300
Subject: [PATCH] more random code

---
 lib/crystal.rb        |  2 +-
 lib/vm/context.rb     | 53 ++++++++++++++++++++++++++++++++++++
 lib/vm/instruction.rb |  6 +++++
 lib/vm/kernel.rb      |  7 +++++
 lib/vm/machine.rb     | 26 +++++++++++++++---
 lib/vm/values.rb      | 63 +++++++++++++++++++++++++++++++++++++++----
 test/runners/foo.rb   |  4 ++-
 test/test_runner.rb   |  7 ++---
 8 files changed, 155 insertions(+), 13 deletions(-)
 create mode 100644 lib/vm/context.rb
 create mode 100644 lib/vm/instruction.rb
 create mode 100644 lib/vm/kernel.rb

diff --git a/lib/crystal.rb b/lib/crystal.rb
index e1d5af56..d7ea5cf3 100644
--- a/lib/crystal.rb
+++ b/lib/crystal.rb
@@ -4,4 +4,4 @@ require "asm/program"
 require "elf/object_writer"
 require 'parser/composed'
 require 'parser/transform'
-
+require "vm/context"
diff --git a/lib/vm/context.rb b/lib/vm/context.rb
new file mode 100644
index 00000000..9d0ec2b2
--- /dev/null
+++ b/lib/vm/context.rb
@@ -0,0 +1,53 @@
+require_relative "kernel"
+
+module Vm
+  class Context
+    def initialize 
+      @locals = {}
+    end
+    def get name
+      @locals[name]
+    end
+  end
+end
+
+# ast classes
+module Parser
+  Expression.class_eval do
+    def compile builder , context
+      raise "abstract #{self.inspect}"
+    end
+  end
+
+  IntegerExpression.class_eval do
+  end
+
+  NameExpression.class_eval do
+  end
+
+  StringExpression.class_eval do
+    def compile builder , context
+      return string
+    end
+  end
+
+  FuncallExpression.class_eval do
+    def compile builder , context
+      arguments = args.collect{|arg| arg.compile(builder , context) }
+      function = context.get(name)
+      unless function
+        function = Vm::Kernel.send(name)
+        context.add_function( name , function )
+      end
+      
+    end    
+  end
+
+  ConditionalExpression.class_eval do
+  end
+
+  AssignmentExpression.class_eval do
+  end
+  FunctionExpression.class_eval do
+  end
+end
diff --git a/lib/vm/instruction.rb b/lib/vm/instruction.rb
new file mode 100644
index 00000000..c9a46b61
--- /dev/null
+++ b/lib/vm/instruction.rb
@@ -0,0 +1,6 @@
+
+module Vm
+  class Instruction
+  end
+  
+end
diff --git a/lib/vm/kernel.rb b/lib/vm/kernel.rb
new file mode 100644
index 00000000..fa07409c
--- /dev/null
+++ b/lib/vm/kernel.rb
@@ -0,0 +1,7 @@
+module Vm
+  module Kernel
+    def self.puts
+      "me"
+    end
+  end
+end
\ No newline at end of file
diff --git a/lib/vm/machine.rb b/lib/vm/machine.rb
index 4eebd8f6..185a2cb1 100644
--- a/lib/vm/machine.rb
+++ b/lib/vm/machine.rb
@@ -1,7 +1,27 @@
 module Vm
-  # the vm machine is what does things. The only one that does things
-  # all things must go through the machine to actually happen
+
+  # Our virtual machine has a number of registers of a given size and uses a stack
+  # So much so standard
+  # But our machine is oo, meaning that the register contents is typed. 
+  # Off course current hardware does not have that (a perceived issue), but for our machine we pretend.
+  # So internally we have at least 8 word registers, one of which is used to keep track of types*
+  # and any number of scratch registers
+  # but externally it's all Values (see there)
+  
+  # * Note that register content is typed externally. Not as in mri, where int's are tagged. Floats can's
+  #   be tagged and lambda should be it's own type, so tagging does not work
+  
+  # Note: subclasses should/will be used once we have the basic architecture clear and working
+  
   class Machine
-    
+  
+    attr_reader :registers
+    attr_reader :scratch
+    attr_reader :pc
+    attr_reader :stack
+    # is often a pseudo register (ie doesn't support move or other operations).
+    # Still, using if to express tests makes sense, not just for 
+    # consistency in this code, but also because that is what is actually done
+    attr_reader :status  
   end
 end
diff --git a/lib/vm/values.rb b/lib/vm/values.rb
index 4b23341f..15d56ff0 100644
--- a/lib/vm/values.rb
+++ b/lib/vm/values.rb
@@ -1,17 +1,70 @@
 module Vm
+  
+  # Values represent the information as it is processed. Different subclasses for different types, 
+  # each type with different operations.
+  # The oprerations on values is what makes a machine do things.
+  # For compilation, values are mopped to the machines registers and the functions (on values) map
+  # to machine instructions
+  
+  # Values are immutable! (that's why they are called values)
+  # Operations on values _always_ produce new values (conceptionally)
+  
+  # Values are a way to reason about (create/validate) instructions. The final executable is mostly 
+  # instrucions.
+  
+  # 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
+    attr :register
+    
+    def initialize reg = nil
+      @register = nil
+    end
   end
-  
-  
+
   class Word < Value
   end
   
-  class Reference < Value
+  class Unsigned < Word
+    
+    def + unsigned
+      unless unsigned.is_a? Unsigned
+        unsigned = Conversion.new( unsigned , Unsigned )
+      end
+      UnsignedAdd.new( self  , unsigned )
+    end
+  end
+
+  class Signed < Word
+    def + signed
+      unless signed.is_a? Signed
+        signed = Conversion.new( signed , Signed )
+      end
+      SignedAdd.new( self  , signed )
+    end
+  end
+  
+  class Float < Word
+  end
+  
+  class Reference < Word
   end
   
   class MemoryReference < Reference
   end
-  
+
   class ObjectReference < Reference
   end
-end
\ No newline at end of file
+
+  class Byte < Value
+  end
+
+end
diff --git a/test/runners/foo.rb b/test/runners/foo.rb
index 94170287..483a7950 100644
--- a/test/runners/foo.rb
+++ b/test/runners/foo.rb
@@ -1,3 +1,5 @@
 def foo(x) 
   a = 5
-end
\ No newline at end of file
+end
+
+foo( 3 )
\ No newline at end of file
diff --git a/test/test_runner.rb b/test/test_runner.rb
index 74babb01..1bf4f887 100644
--- a/test/test_runner.rb
+++ b/test/test_runner.rb
@@ -25,9 +25,10 @@ class TestRunner < MiniTest::Test
     #link
     # execute
     # check result ?
-    puts string
-    puts " "
-    puts tree.inspect
+    context = Vm::Context.new
+    builder = Asm::Program.new
+    compiled = tree.compile( builder , context )
+    puts compiled.inspect
   end
 
 end
\ No newline at end of file