From 7216300452de09c683673bad2e3d894bcebfbd2b Mon Sep 17 00:00:00 2001
From: Torsten Ruger <torsten@villataika.fi>
Date: Thu, 30 Jul 2015 19:18:12 +0300
Subject: [PATCH] add interpreter here (moved from debugger)

---
 Gemfile.lock                   |   2 +-
 lib/interpreter/eventable.rb   |  37 +++++++
 lib/interpreter/interpreter.rb | 174 +++++++++++++++++++++++++++++++++
 test/graph_helper.rb           |  22 -----
 test/interpreter/helper.rb     |   2 +
 test/interpreter/test_all.rb   |   1 +
 test/interpreter/test_puts.rb  |  83 ++++++++++++++++
 test/test_all.rb               |   5 +-
 8 files changed, 301 insertions(+), 25 deletions(-)
 create mode 100644 lib/interpreter/eventable.rb
 create mode 100644 lib/interpreter/interpreter.rb
 delete mode 100644 test/graph_helper.rb
 create mode 100644 test/interpreter/helper.rb
 create mode 100644 test/interpreter/test_all.rb
 create mode 100644 test/interpreter/test_puts.rb

diff --git a/Gemfile.lock b/Gemfile.lock
index affd8107..3fa90e00 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -1,6 +1,6 @@
 GIT
   remote: git://github.com/salama/salama-arm.git
-  revision: 9a1c18dfe974909e02e33f7b086ac516e3384f4b
+  revision: 0bd5091e3f284ecf040e0086a41d2449cd5afb7a
   specs:
     salama-arm (0.0.1)
 
diff --git a/lib/interpreter/eventable.rb b/lib/interpreter/eventable.rb
new file mode 100644
index 00000000..a7274304
--- /dev/null
+++ b/lib/interpreter/eventable.rb
@@ -0,0 +1,37 @@
+# A simple event registering/triggering module to mix into classes.
+# Events are stored in the `@events` ivar.
+module Eventable
+
+  # Register a handler for the given event name.
+  # The event name is the method name called on the handler object
+  #
+  #   obj.on(:foo , some_object_that_implements foo( whateverargs)
+  #
+  # @param [String, Symbol] name event name
+  # @param [Object] object handling the event, ie implement the function name
+  # @return handler
+  def register_event(name, handler)
+    event_table[name] << handler
+    handler
+  end
+
+  def unregister_event(name, handler)
+    event_table[name].delete handler
+  end
+
+  def event_table
+    return @event_table if @event_table
+    @event_table = Hash.new { |hash, key| hash[key] = [] }
+  end
+
+  # Trigger the given event name and passes all args to each handler
+  # for this event.
+  #
+  #   obj.trigger(:foo)
+  #   obj.trigger(:foo, 1, 2, 3)
+  #
+  # @param [String, Symbol] name event name to trigger
+  def trigger(name, *args)
+    event_table[name].each { |handler| handler.send( name.to_sym , *args) }
+  end
+end
diff --git a/lib/interpreter/interpreter.rb b/lib/interpreter/interpreter.rb
new file mode 100644
index 00000000..62945599
--- /dev/null
+++ b/lib/interpreter/interpreter.rb
@@ -0,0 +1,174 @@
+
+require_relative "eventable"
+
+module Interpreter
+  class Interpreter
+    # fire events for changed pc and register contents
+    include Eventable
+
+    # current instruction or pc
+    attr_reader :instruction
+
+    # current instruction or pc
+    attr_reader :clock
+
+    # an (arm style) link register. store the return address to return to
+    attr_reader :link
+
+    # current executing block. since this is not a hardware simulator this is luxury
+    attr_reader :block
+
+    # the registers, 16
+    attr_reader :registers
+
+    # collect the output
+    attr_reader :stdout
+
+    attr_reader :state
+
+    def initialize
+      @state = "runnnig"
+      @stdout = ""
+      @registers = {}
+      @clock = 0
+      (0...16).each do |r|
+        set_register "r#{r}".to_sym , "r#{r}:unknown"
+      end
+    end
+
+    def start bl
+      set_block  bl
+    end
+
+    def set_block bl
+      return if @block == bl
+      raise "Error, nil block" unless bl
+      old = @block
+      @block = bl
+      trigger(:block_changed , old , bl)
+      set_instruction bl.codes.first
+    end
+
+    def set_instruction i
+      @state = "exited" unless i
+      return if @instruction == i
+      old = @instruction
+      @instruction = i
+      trigger(:instruction_changed, old , i)
+    end
+
+    def get_register( reg )
+      reg = reg.symbol if reg.is_a? Register::RegisterReference
+      raise "Not a register #{reg}" unless Register::RegisterReference.look_like_reg(reg)
+      @registers[reg]
+    end
+
+    def set_register reg , val
+      old = get_register( reg ) # also ensures format
+      return if old === val
+      reg = reg.symbol if reg.is_a? Register::RegisterReference
+      @registers[reg] = val
+      trigger(:register_changed, reg ,  old , val)
+    end
+
+    def tick
+      return unless @instruction
+      @clock += 1
+      name = @instruction.class.name.split("::").last
+      fetch = send "execute_#{name}"
+      return unless fetch
+      fetch_next_intruction
+    end
+
+    def fetch_next_intruction
+      if(@instruction != @block.codes.last)
+        set_instruction @block.codes[  @block.codes.index(@instruction)  + 1]
+      else
+        next_b = @block.method.source.blocks.index(@block) + 1
+        set_block @block.method.source.blocks[next_b]
+      end
+    end
+
+    def object_for reg
+      id = get_register(reg)
+      Virtual.machine.objects[id]
+    end
+
+    # Instruction interpretation starts here
+    def execute_Branch
+      target = @instruction.block
+      set_block target
+      false
+    end
+
+    def execute_LoadConstant
+      to = @instruction.register
+      value = @instruction.constant.object_id
+      set_register( to , value )
+      true
+    end
+
+    def execute_GetSlot
+      object = object_for( @instruction.array )
+      value = object.internal_object_get( @instruction.index )
+      value = value.object_id unless value.is_a? Integer
+      set_register( @instruction.register , value )
+      true
+    end
+
+    def execute_SetSlot
+      value = object_for( @instruction.register )
+      object = object_for( @instruction.array )
+      object.internal_object_set( @instruction.index , value )
+      trigger(:object_changed, @instruction.array )
+      true
+    end
+
+    def execute_RegisterTransfer
+      value = get_register @instruction.from
+      set_register @instruction.to , value
+      true
+    end
+
+    def execute_FunctionCall
+      @link = [@block , @instruction]
+      next_block = @instruction.method.source.blocks.first
+      set_block next_block
+      false
+    end
+
+    def execute_SaveReturn
+      object = object_for @instruction.register
+      raise "save return has nothing to save" unless @link
+      trigger(:object_changed, @instruction.register )
+      object.internal_object_set @instruction.index , @link
+      @link = nil
+      true
+    end
+
+    def execute_Syscall
+      name = @instruction.name
+      case name
+      when :putstring
+        str = object_for( :r1 ) # should test length, ie r2
+        raise "NO string for putstring #{str.class}:#{str.object_id}" unless str.is_a? Symbol
+        @stdout += str.to_s
+      when :exit
+        set_instruction(nil)
+        return false
+      else
+        raise "un-implemented syscall #{name}"
+      end
+      true
+    end
+
+    def execute_FunctionReturn
+      object = object_for( @instruction.register )
+      #wouldn't need to assign to link, but makes testing easier
+      link = object.internal_object_get( @instruction.index )
+      @block , @instruction = link
+      # we jump back to the call instruction. so it is as if the call never happened and we continue
+      true
+    end
+  end
+end
diff --git a/test/graph_helper.rb b/test/graph_helper.rb
deleted file mode 100644
index ce98bbfc..00000000
--- a/test/graph_helper.rb
+++ /dev/null
@@ -1,22 +0,0 @@
-require 'gritty'
-
-def dump(obj, name)
-  g = digraph do
-    graph_attribs << 'bgcolor=black'
-
-    node_attribs << 'color=white'
-    node_attribs << 'penwidth=2'
-    node_attribs << 'fontcolor=white'
-    node_attribs << 'labelloc=c'
-    node_attribs << 'fontname="Courier New"'
-    node_attribs << 'fontsize=36'
-
-    edge_attribs << 'color=white'
-    edge_attribs << 'penwidth=2'
-
-    builder = Gritty::NodeBuilder.new self
-    builder.build obj, 'root'
-
-    save name, 'pdf'
-  end
-end
diff --git a/test/interpreter/helper.rb b/test/interpreter/helper.rb
new file mode 100644
index 00000000..a6946d19
--- /dev/null
+++ b/test/interpreter/helper.rb
@@ -0,0 +1,2 @@
+require_relative "../helper"
+require "interpreter/interpreter"
diff --git a/test/interpreter/test_all.rb b/test/interpreter/test_all.rb
new file mode 100644
index 00000000..1b24e62a
--- /dev/null
+++ b/test/interpreter/test_all.rb
@@ -0,0 +1 @@
+require_relative "test_puts"
diff --git a/test/interpreter/test_puts.rb b/test/interpreter/test_puts.rb
new file mode 100644
index 00000000..72f96ef1
--- /dev/null
+++ b/test/interpreter/test_puts.rb
@@ -0,0 +1,83 @@
+require_relative "helper"
+
+class InterpreterTest < MiniTest::Test
+
+  def setup
+    Virtual.machine.boot
+    code = Ast::ExpressionList.new( [Ast::CallSiteExpression.new(:putstring, [] ,Ast::StringExpression.new("Hello again"))])
+    Virtual::Compiler.compile( code , Virtual.machine.space.get_main )
+    Virtual.machine.run_before "Register::CallImplementation"
+    @interpreter = Interpreter::Interpreter.new
+    @interpreter.start Virtual.machine.init
+  end
+
+  def ticks num
+    last = nil
+    num.times do
+      last = @interpreter.instruction
+      @interpreter.tick
+    end
+    return last
+  end
+  
+  def test_branch
+    was = @interpreter.block
+    assert_equal Register::Branch , ticks(1).class
+    assert was != @interpreter.block
+  end
+  def test_load
+    assert_equal Register::LoadConstant ,  ticks(2).class
+    assert_equal Parfait::Space ,  Virtual.machine.objects[ @interpreter.get_register(:r1)].class
+    assert_equal :r1,  @interpreter.instruction.array.symbol
+  end
+  def test_get
+    assert_equal Register::GetSlot , ticks(3).class
+    assert @interpreter.get_register( :r3 )
+    assert @interpreter.get_register( :r3 ).is_a? Integer
+  end
+  def test_transfer
+    transfer = ticks 5
+    assert_equal Register::RegisterTransfer ,  transfer.class
+    assert_equal @interpreter.get_register(transfer.to) , @interpreter.get_register(transfer.from)
+  end
+  def test_call
+    assert_equal Register::FunctionCall ,  ticks(7).class
+    assert @interpreter.link
+  end
+  def test_save
+    done = ticks(8)
+    assert_equal Register::SaveReturn ,  done.class
+    assert @interpreter.get_register done.register.symbol
+  end
+
+  def test_chain
+    ["Branch" , "LoadConstant" , "GetSlot" , "SetSlot" , "RegisterTransfer" ,
+     "GetSlot" , "FunctionCall" , "SaveReturn" , "LoadConstant"  , "SetSlot" ,
+     "GetSlot" ,  "GetSlot" , "SetSlot" , "LoadConstant" , "SetSlot" ,
+     "RegisterTransfer" ,  "GetSlot" ,  "FunctionCall" , "SaveReturn" , "RegisterTransfer" ,
+     "Syscall" , "RegisterTransfer" , "RegisterTransfer" , "SetSlot" , "GetSlot" ,
+     "GetSlot" , "RegisterTransfer" ,"GetSlot" , "GetSlot","GetSlot",
+     "FunctionReturn" , "RegisterTransfer" , "Syscall" , "NilClass"].each_with_index do |name , index|
+      got = ticks(1)
+      assert got.class.name.index(name) , "Wrong class for #{index+1}, expect #{name} , got #{got}"
+    end
+  end
+
+  def test_putstring
+    done = ticks(21)
+    assert_equal Register::Syscall ,  done.class
+    assert_equal "Hello again" , @interpreter.stdout
+  end
+
+  def test_return
+    done = ticks(31)
+    assert_equal Register::FunctionReturn ,  done.class
+    assert @interpreter.block.is_a?(Virtual::Block)
+    assert @interpreter.instruction.is_a?(Register::Instruction) , "not instruction #{@interpreter.instruction}"
+  end
+
+  def test_exit
+    done = ticks(34)
+    assert_equal NilClass ,  done.class
+  end
+end
diff --git a/test/test_all.rb b/test/test_all.rb
index 10d89efa..e6bc93fe 100644
--- a/test/test_all.rb
+++ b/test/test_all.rb
@@ -1,8 +1,9 @@
-# All working tests (ahm), still working on the others, so no use to be constantly reminded
+require_relative "compiler/test_all"
+
 require_relative "parfait/test_all"
 
 require_relative "fragments/test_all"
 
 require_relative "virtual/test_all"
 
-require_relative "compiler/test_all"
+require_relative "interpreter/test_all"