From d7f31e7f397b57304f279e2e3232e0bcf5c606d9 Mon Sep 17 00:00:00 2001
From: Torsten Ruger <torsten@villataika.fi>
Date: Tue, 13 May 2014 16:24:19 +0300
Subject: [PATCH] introduce constant class and add block to compile
 signature(wip, work in progress)

---
 lib/arm/arm_machine.rb          | 10 +++-
 lib/arm/assembler.rb            |  4 +-
 lib/arm/logic_helper.rb         |  4 +-
 lib/arm/memory_instruction.rb   |  2 +-
 lib/ast/basic_expressions.rb    | 16 +++----
 lib/ast/expression.rb           |  2 +-
 lib/ast/function_expression.rb  | 20 ++++----
 lib/ast/operator_expressions.rb | 54 +++++++++------------
 lib/ast/while_expression.rb     |  8 ++++
 lib/parser/operators.rb         |  4 +-
 lib/parslet/transform.rb        |  2 +-
 lib/vm/constants.rb             | 51 ++++++++++++++++++++
 lib/vm/function_call.rb         | 22 +++------
 lib/vm/machine.rb               |  2 +-
 lib/vm/values.rb                | 84 +++++++--------------------------
 15 files changed, 145 insertions(+), 140 deletions(-)
 create mode 100644 lib/vm/constants.rb

diff --git a/lib/arm/arm_machine.rb b/lib/arm/arm_machine.rb
index c2b98001..b81941b2 100644
--- a/lib/arm/arm_machine.rb
+++ b/lib/arm/arm_machine.rb
@@ -30,7 +30,15 @@ module Arm
         end
       end
     end
-    
+
+    def integer_less_or_equal left , right
+      cmp(:left => left , :right => right )
+    end
+
+    def integer_plus left , right
+      add(:left => left , :right => right )
+    end
+
     def word_load value , reg
       raise "not a register :#{reg}:" unless reg.class == Symbol
       mov( :left => reg , :right => value )
diff --git a/lib/arm/assembler.rb b/lib/arm/assembler.rb
index 3fb4850b..e4217468 100644
--- a/lib/arm/assembler.rb
+++ b/lib/arm/assembler.rb
@@ -39,11 +39,11 @@ module Arm
 
     # Add a string to the string table. Strings are global and constant. So only one copy of each 
     # string exists
-    # Internally StringLiterals are created and stored and during assembly written after the blocks
+    # Internally StringConstants are created and stored and during assembly written after the blocks
     def add_string str
       code = @string_table[str]
       return code if code
-      data = Vm::StringLiteral.new(str)
+      data = Vm::StringConstant.new(str)
       @string_table[str] = data
     end
 
diff --git a/lib/arm/logic_helper.rb b/lib/arm/logic_helper.rb
index e5eea858..4ba66278 100644
--- a/lib/arm/logic_helper.rb
+++ b/lib/arm/logic_helper.rb
@@ -22,7 +22,7 @@ module Arm
 
     #(stays in subclases, while build is overriden to provide different arguments)
     def do_build(arg)      
-      if arg.is_a?(Vm::StringLiteral)
+      if arg.is_a?(Vm::StringConstant)
         # do pc relative addressing with the difference to the instuction
         # 8 is for the funny pipeline adjustment (ie oc pointing to fetch and not execute)
         arg = Arm::NumLiteral.new( arg.position - self.position - 8 )
@@ -31,7 +31,7 @@ module Arm
       if( arg.is_a? Fixnum ) #HACK to not have to change the code just now
         arg = Arm::NumLiteral.new( arg )
       end
-      if( arg.is_a? Vm::Signed ) #HACK to not have to change the code just now
+      if( arg.is_a? Vm::Integer ) #HACK to not have to change the code just now
         arg = Arm::NumLiteral.new( arg.value )
       end
       if (arg.is_a?(Arm::NumLiteral))
diff --git a/lib/arm/memory_instruction.rb b/lib/arm/memory_instruction.rb
index 3144eaee..c8b84f54 100644
--- a/lib/arm/memory_instruction.rb
+++ b/lib/arm/memory_instruction.rb
@@ -50,7 +50,7 @@ module Arm
             raise "reference offset too large/small (max 4095) #{arg} #{inspect}"
           end
         end
-      elsif (arg.is_a?(Vm::StringLiteral)) #use pc relative
+      elsif (arg.is_a?(Vm::StringConstant)) #use pc relative
         @rn = :pc
         @operand = arg.position - self.position  - 8 #stringtable is after code
         @add_offset = 1
diff --git a/lib/ast/basic_expressions.rb b/lib/ast/basic_expressions.rb
index 624697d6..2256aa5d 100644
--- a/lib/ast/basic_expressions.rb
+++ b/lib/ast/basic_expressions.rb
@@ -13,8 +13,8 @@ module Ast
     def to_s
       value.to_s
     end
-    def compile context
-      Vm::Signed.new value
+    def compile context , into
+      Vm::Integer.new value
     end
     def attributes
       [:value]
@@ -26,10 +26,10 @@ module Ast
     def initialize name
       @name = name
     end
-    def compile context
-      variable = Vm::Variable.new(@name)
-      context.locals[@name] = variable
-      variable
+    # compiling a variable resolves it. 
+    # if it wasn't defined, nli is returned 
+    def compile context , into
+      context.locals[name]
     end
     def inspect
       self.class.name + '.new("' + name + '")'
@@ -51,8 +51,8 @@ module Ast
       self.class.name + '.new("' + string + '")'
     end
 
-    def compile context
-      value = Vm::StringLiteral.new(string)
+    def compile context , into
+      value = Vm::StringConstant.new(string)
       context.program.add_object value 
       value
     end
diff --git a/lib/ast/expression.rb b/lib/ast/expression.rb
index 728374a6..795bc79c 100644
--- a/lib/ast/expression.rb
+++ b/lib/ast/expression.rb
@@ -12,7 +12,7 @@ module Ast
     def eval 
       raise "abstract #{self}"
     end
-    def compile context
+    def compile context , into
       raise "abstract #{self}"
     end
     def attributes
diff --git a/lib/ast/function_expression.rb b/lib/ast/function_expression.rb
index 4b57e5d8..ce5b5b8a 100644
--- a/lib/ast/function_expression.rb
+++ b/lib/ast/function_expression.rb
@@ -16,27 +16,31 @@ module Ast
     def to_s
       "def #{name}( " + params.join(",") + ") \n" + block.join("\n") + "end\n"
     end
-    def compile context
-      raise self.to_s
+    def compile context , into 
+      raise "function does not compile into anything #{self}" if into
       parent_locals = context.locals
       context.locals = {}
       args = []
-      params.each do |param|
-        args << param.compile(context) # making the argument a local
+      params.each_with_index do |param , index|
+        arg = param.name
+        arg_value = Vm::Integer.new(index)
+        context.locals[arg] = arg_value
+        args << arg_value
       end
-#      args = params.collect{|p| Vm::Value.type p.name }
-      function = Vm::Function.new(name ,args )
+      function = Vm::Function.new(name , args )
       context.program.add_function function
+      into = function.entry
       block.each do |b|
-        compiled = b.compile context
+        compiled = b.compile(context , into)
         if compiled.is_a? Vm::Block
+          into = compiled
           he.breaks.loose
         else
           function.body.add_code compiled
         end
         puts compiled.inspect
       end
-      context.locals = parent_locals if parent_locals
+      context.locals = parent_locals
       function
     end
 
diff --git a/lib/ast/operator_expressions.rb b/lib/ast/operator_expressions.rb
index 1793a365..30201c03 100644
--- a/lib/ast/operator_expressions.rb
+++ b/lib/ast/operator_expressions.rb
@@ -7,13 +7,14 @@ module Ast
     def initialize name, args
       @name , @args = name , args
     end
-    def compile context
-      fun = Vm::FunctionCall.new( name , args.collect{ |a| a.compile(context) } )
-      fun.assign_function context
-      fun.load_args
-      fun.do_call
+    def compile context , into
+      params = args.collect{ |a| a.compile(context, into) }
+      fun = Vm::FunctionCall.new( name ,  params )
+      fun.load_args into
+      fun.do_call into
       fun
     end
+    
     def inspect
       self.class.name + ".new(" + name.inspect + ", ["+ 
         args.collect{|m| m.inspect }.join( ",") +"] )"  
@@ -41,35 +42,24 @@ module Ast
     def to_s
       "#{left} #{operator} #{right}"
     end
-    def compile context
-      parent_locals = context.locals
-      context.locals = {}
-      args = []
-
-      #assignemnt
-      value = @assigned.compile(context)
-      variable = Vm::Variable.new @assignee , :r0 , value
-      context.locals[@assignee] = variable
-      variable
-
-
-      params.each do |param|
-        args << param.compile(context) # making the argument a local
+    def compile context , into
+      r_val = right.compile(context , into)
+      
+      if operator == "="    # assignemnt
+        raise "Can only assign variables, not #{left}" unless left.is_a?(NameExpression) 
+        context.locals[left.name] = r_val
+        return r_val
       end
-#      args = params.collect{|p| Vm::Value.type p.name }
-      function = Vm::Function.new(name ,args )
-      context.program.add_function function
-      block.each do |b|
-        compiled = b.compile context
-        if compiled.is_a? Vm::Block
-          he.breaks.loose
-        else
-          function.body.add_code compiled
-        end
-        puts compiled.inspect
+      l_val = left.compile(context , into)
+
+      case operator
+      when ">"
+        code = l_val.less_or_equal r_val
+      when "+"
+        code = l_val.plus r_val
+      else
+        raise "unimplemented operator #{operator} #{self}"
       end
-      context.locals = parent_locals if parent_locals
-      function
     end
   end
 end
\ No newline at end of file
diff --git a/lib/ast/while_expression.rb b/lib/ast/while_expression.rb
index e20e4def..5b0039a2 100644
--- a/lib/ast/while_expression.rb
+++ b/lib/ast/while_expression.rb
@@ -13,6 +13,14 @@ module Ast
     def attributes
       [:condition, :body]
     end
+    def compile context , into
+      cond_val = condition.compile(context , into)
+      #set up branches for bodies
+      body.each do |part|
+        part.compile(context , into )
+      end
+      return cond_val
+    end
   end
 
   
diff --git a/lib/parser/operators.rb b/lib/parser/operators.rb
index 2d0a6d36..dac03e63 100644
--- a/lib/parser/operators.rb
+++ b/lib/parser/operators.rb
@@ -8,7 +8,7 @@ module Parser
     rule(:bit_and) { str('&') >> space?}
     rule(:bit_or) { str('|') >> space?}
     rule(:greater_equal) { str('>=') >> space?}
-    rule(:smaller_equal) { str('<=') >> space?}
+    rule(:less_or_equal) { str('<=') >> space?}
     rule(:larger) { str('>') >> space?}
     rule(:smaller) { str('<') >> space?}
     rule(:identity) { str('===') >> space?}
@@ -31,7 +31,7 @@ module Parser
                                      [bit_and, 90, :left],
                                      [bit_or, 90, :right],
                                      [greater_equal, 80, :left],
-                                     [smaller_equal, 80, :left],
+                                     [less_or_equal, 80, :left],
                                      [larger, 80, :left],
                                      [smaller, 80, :left],
                                      [identity, 70, :right],
diff --git a/lib/parslet/transform.rb b/lib/parslet/transform.rb
index b04fa29d..5d999639 100644
--- a/lib/parslet/transform.rb
+++ b/lib/parslet/transform.rb
@@ -22,7 +22,7 @@ require 'parslet/pattern'
 #
 #   class Example < Parslet::Transform
 #     rule(:string => simple(:x)) {  # (1)
-#       StringLiteral.new(x)
+#       StringConstant.new(x)
 #     }
 #   end
 #
diff --git a/lib/vm/constants.rb b/lib/vm/constants.rb
new file mode 100644
index 00000000..bd00d521
--- /dev/null
+++ b/lib/vm/constants.rb
@@ -0,0 +1,51 @@
+module Vm
+  
+  # constants are the stuff that you embedd in the program as numbers or strings. 
+  # Another way to think about them is as Operands, they have no seperate "identity"
+  # and usually end up embedded in the instructions. ie your basic foo + 4 will encode
+  # the 4 in the instruction opcode. The 4 is not accessible anywhere else.
+  # When it should be usable in other forms, the constant must become a Value first 
+  class Constant < Value
+    
+  end
+
+
+  class IntegerConstant < Constant
+    def init int
+      @integer = int
+    end
+    attr_reader :integer
+  end
+
+  # The name really says it all.
+  # The only interesting thing is storage.
+  # Currently string are stored "inline" , ie in the code segment. 
+  # Mainly because that works an i aint no elf expert.
+  
+  class StringConstant < Constant
+    attr_reader :string
+    # currently aligned to 4 (ie padded with 0) and off course 0 at the end
+    def initialize str
+      length = str.length 
+      # rounding up to the next 4 (always adding one for zero pad)
+      pad =  ((length / 4 ) + 1 ) * 4 - length
+      raise "#{pad} #{self}" unless pad >= 1
+      @string = str + "\x00" * pad 
+    end
+
+    def load reg_num
+      Machine.instance.string_load self , reg_num
+    end
+
+    # the strings length plus padding
+    def length
+      string.length
+    end
+    
+    # just writing the string
+    def assemble(io)
+      io << string
+    end
+  end
+  
+end
\ No newline at end of file
diff --git a/lib/vm/function_call.rb b/lib/vm/function_call.rb
index 939075b1..da621a34 100644
--- a/lib/vm/function_call.rb
+++ b/lib/vm/function_call.rb
@@ -2,31 +2,23 @@ module Vm
 
   # name and args , return
 
-  class FunctionCall < Block
+  class FunctionCall < Value
 
     def initialize(name , args)
-      super(name)
+      @name = name
       @args = args
       @function = nil
     end
-    attr_reader  :function , :args
+    attr_reader  :function , :args , :name
     
-    def assign_function context
-      @function = context.program.get_function @name
-      if @function
-        raise "error #{self} , #{@function.args.length} != #{args.length}" if @function.arity != args.length
-      else
-        @function = context.program.get_or_create_function @name
-      end
-    end
-    def load_args
+    def load_args into
       args.each_with_index do |arg , index|
-        add_code arg.load("r#{index}".to_sym)
+        into.add_code arg.load("r#{index}".to_sym)
       end
     end
 
-    def do_call
-      add_code Machine.instance.function_call self
+    def do_call into
+      into.add_code Machine.instance.function_call self
     end
   end
 end
diff --git a/lib/vm/machine.rb b/lib/vm/machine.rb
index 9d3f60c2..68715776 100644
--- a/lib/vm/machine.rb
+++ b/lib/vm/machine.rb
@@ -14,7 +14,7 @@ module Vm
   # A Machines main responsibility in the framework is to instantiate Instruction
 
   # Value functions are mapped to machines by concatenating the values class name + the methd name
-  # Example:  SignedValue.plus( value ) ->  Machine.signed_plus (value )
+  # Example:  IntegerValue.plus( value ) ->  Machine.signed_plus (value )
   
   # Also, shortcuts are created to easily instantiate Instruction objects. The "standard" set of instructions
   # (arm-influenced) provides for normal operations on a register machine, 
diff --git a/lib/vm/values.rb b/lib/vm/values.rb
index 71d692fc..05883d6c 100644
--- a/lib/vm/values.rb
+++ b/lib/vm/values.rb
@@ -21,27 +21,23 @@ module Vm
   # just a base class for data. not sure how this will be usefull (may just have read too much llvm)
   class Value < Code
 
-    def initialize value
-      @value = value
-    end
-    attr_reader :value
-    
-    #naming convention to infer types in kernel functions. Kernel types are basic types, ie see below
-    # 
-    def self.type name
-      parts = name.split("_")
-      t = "Basic"
-      if parts[1]
-        t = parts[1]
-      end
-      t
+
+    def type
+      self.class
     end
   end
 
+  # This is what it is when we don't know what it is.
+  # Must be promoted to A Word-Value to to anything
+  # remembering that our oo machine is typed, no overloading or stuff
   class Word < Value
-    def load reg
-      Machine.instance.word_load self , reg
+
+    attr_accessor :register
+
+    def initialize reg
+      register = reg
     end
+
     def length
       4
     end
@@ -54,59 +50,15 @@ module Vm
     end
   end
 
-  class Signed < Word
-    def plus signed
-      Machine.instance.signed_plus self , signed
-    end
-  end
+  class Integer < Word
 
-  class Variable < Value
-    attr_reader :name , :register
-    def initialize name , register = nil , val = nil
-      super(val)
-      @register = register
-      @name = name
-    end
-    def length
-      @value.length
-    end
-    def assemble io
-      @value.load @register
-    end
-  end
-
-  # The name really says it all.
-  # The only interesting thing is storage.
-  # Currently string are stored "inline" , ie in the code segment. 
-  # Mainly because that works an i aint no elf expert.
-  
-  class StringLiteral < Value
-    
-    # currently aligned to 4 (ie padded with 0) and off course 0 at the end
-    def initialize(str)
-      super(str)
-      length = str.length 
-      # rounding up to the next 4 (always adding one for zero pad)
-      pad =  ((length / 4 ) + 1 ) * 4 - length
-      raise "#{pad} #{self}" unless pad >= 1
-      @value = str + "\x00" * pad 
-    end
-    def string
-      @value
+    def less_or_equal right
+      Machine.instance.integer_less_or_equal self , right
     end
 
-    def load reg_num
-      Machine.instance.string_load self , reg_num
-    end
-
-    # the strings length plus padding
-    def length
-      string.length
-    end
-    
-    # just writing the string
-    def assemble(io)
-      io << string
+    def plus right
+      Machine.instance.integer_plus self , right
     end
   end
 end
+require_relative "constants"
\ No newline at end of file