From 23f95fe68cdc0ffa0def1ee54621e1bb2ae65fb3 Mon Sep 17 00:00:00 2001
From: Danila Fedorin <danila.fedorin@gmail.com>
Date: Fri, 27 Jul 2018 00:06:33 -0700
Subject: [PATCH] Intermediate commit. Remove type restrictions. Code gen is
 very broken

---
 src/chalk.cr          |   1 -
 src/chalk/codegen.cr  | 125 ++++++++++++++++++++++++++++++++++--------
 src/chalk/compiler.cr |  18 ++++--
 src/chalk/ir.cr       |  47 +++++++++++++---
 src/chalk/parsers.cr  |   3 +-
 src/chalk/table.cr    |   8 +--
 src/chalk/tree.cr     |  68 +++++++++++------------
 src/chalk/ui.cr       |   2 +-
 8 files changed, 196 insertions(+), 76 deletions(-)

diff --git a/src/chalk.cr b/src/chalk.cr
index 0443cb5..226b0bc 100644
--- a/src/chalk.cr
+++ b/src/chalk.cr
@@ -5,7 +5,6 @@ module Chalk
   config = Config.parse!
   exit unless config.validate!
 
-  generator = CodeGenerator.new (Table.new)
   compiler = Compiler.new config
   compiler.run
 end
diff --git a/src/chalk/codegen.cr b/src/chalk/codegen.cr
index 402d21f..4f9b84b 100644
--- a/src/chalk/codegen.cr
+++ b/src/chalk/codegen.cr
@@ -2,53 +2,81 @@ require "./ir.cr"
 
 module Chalk
   class CodeGenerator
-    def initialize(@table : Table)
+    def initialize(table, @function : TreeFunction)
       @register = 0
       @instructions = [] of Instruction
-      @block_edges = [] of Int32
+      @table = Table.new table
+
+      @function.params.each do |param|
+        @table[param] = VarEntry.new @register
+        @register += 1
+      end
     end
 
     private def load(into, value)
-      @instructions << LoadInstruction.new into, value.to_i32
+      inst = LoadInstruction.new into, value.to_i32
+      @instructions << inst
+      return inst
     end
 
     private def loadr(into, from)
-      @instructions << LoadRegInstruction.new into, from
+      inst = LoadRegInstruction.new into, from
+      @instructions << inst
+      return inst
     end
 
     private def op(op, into, from)
-      @instructions << OpRegInstruction.new op, into, from
+      inst = OpRegInstruction.new op, into, from
+      @instructions << inst
+      return inst
+    end
+
+    private def jeq(rel, l, r)
+      inst = JumpEqRegInstruction.new rel, l, r
+      @instructions << inst
+      return inst
     end
 
     private def store(up_to)
-      @instructions << StoreInstruction.new up_to
+      inst = StoreInstruction.new up_to
+      @instructions << inst
+      return inst
     end
 
     private def restore(up_to)
-      @instructions << RestoreInstruction.new up_to
+      inst = RestoreInstruction.new up_to
+      @instructions << inst
+      return inst
     end
 
     private def ret(reg)
-      @instructions << ReturnInstruction.new reg
+      inst =  ReturnInstruction.new reg
+      @instructions << inst
+      return inst
     end
 
-    def generate(tree : Tree, target : Int32)
+    def generate!(tree, target)
       case tree
       when TreeId
         entry = @table[tree.id]?
         raise "Unknown variable" unless entry &&
                                         entry.is_a?(VarEntry)
-        loadr target, entry.as(VarEntry).register
+        loadr target, entry.register
       when TreeLit
         load target, tree.lit
       when TreeOp
-        generate tree.left, target
-        generate tree.right, @register
-        op tree.op, target, @register
+        into = @register
+        @register += 1
+        generate! tree.left, target
+        generate! tree.right, into
+        @register -= 1
+        op tree.op, target, into
       when TreeBlock
+        register = @register
         tree.children.each do |child|
-          generate child, @register
+          generate! child, @register
         end
+        @register = register
       when TreeVar
         entry = @table[tree.name]?
         if entry == nil
@@ -57,22 +85,75 @@ module Chalk
           @table[tree.name] = entry
         end
         raise "Unknown variable" unless entry.is_a?(VarEntry)
-        generate tree.expr, entry.register
+        generate! tree.expr, entry.register
       when TreeAssign
         entry = @table[tree.name]?
         raise "Unknown variable" unless entry &&
                                         entry.is_a?(VarEntry)
-        generate tree.expr, entry.as(VarEntry).register
+        generate! tree.expr, entry.register
+      when TreeIf
+        cond_target = @register
+        @register += 1
+
+        generate! tree.condition, cond_target
+        load cond_target + 1, 0
+        jump_inst = jeq 0, cond_target, cond_target + 1
+        @register -= 1
+
+        old_size = @instructions.size
+        generate! tree.block, @register
+        jump_inst.offset = @instructions.size - old_size + 1
+
+        generate! tree.otherwise, @register if tree.otherwise
       when TreeReturn
-        generate tree.rvalue, target
-        ret target
+        into = @register
+        @register += 1
+        generate! tree.rvalue, into
+        @register -= 1
+        ret into
       end
     end
 
-    def generate(tree : Tree)
-      generate(tree, 0)
-      @block_edges << @instructions.size
-      @block_edges.sort!
+    private def check_dead(inst)
+      if inst.is_a?(LoadRegInstruction)
+        return inst.from == inst.into
+      end
+      return false
+    end
+
+    private def optimize!(range)
+      offset = 0
+      range.each do |index|
+        if check_dead(@instructions[index + offset])
+          @instructions.delete_at(index + offset)
+          offset -= 1
+        end
+      end
+      return offset
+    end
+
+    private def optimize!
+      block_boundaries = [ @instructions.size ]
+      @instructions.each_with_index do |inst, i|
+        if inst.is_a?(JumpEqRegInstruction) ||
+           inst.is_a?(JumpEqInstruction)
+            block_boundaries << (inst.offset + i)
+        end
+      end
+      block_boundaries.sort!
+
+      previous = 0
+      offset = 0
+      block_boundaries.each do |boundary|
+        range = (previous + offset)...(boundary + offset)
+        offset += optimize!(range)
+        previous = boundary
+      end
+    end
+
+    def generate!
+      generate!(@function.block, @register)
+      optimize!
       return @instructions
     end
   end
diff --git a/src/chalk/compiler.cr b/src/chalk/compiler.cr
index 840b1c0..0ad5f9f 100644
--- a/src/chalk/compiler.cr
+++ b/src/chalk/compiler.cr
@@ -40,11 +40,15 @@ module Chalk
     end
 
     private def generate_code(trees, table)
+      code = {} of String => Array(Instruction)
       trees.each do |tree|
-        generator = CodeGenerator.new table
-        instructions = generator.generate tree.as(TreeFunction).block
-        instructions.each { |it| puts it }
+        tree = tree.as(TreeFunction)
+        generator = CodeGenerator.new table, tree
+        @logger.debug("Generating code for #{tree.name}")
+        instructions = generator.generate!
+        code[tree.name] = instructions
       end
+      return code
     end
 
     private def run_tree
@@ -57,7 +61,13 @@ module Chalk
     private def run_intermediate
       trees = create_trees(@config.file)
       table = process_initial(trees)
-      generate_code(trees, table)
+      raise "No main function!" unless table["main"]?
+      code = generate_code(trees, table)
+      code.each do |name, insts|
+        puts "Code for #{name}:"
+        insts.each { |it| puts it }
+        puts "-----"
+      end
     end
 
     private def run_binary
diff --git a/src/chalk/ir.cr b/src/chalk/ir.cr
index a1959b5..b0cac24 100644
--- a/src/chalk/ir.cr
+++ b/src/chalk/ir.cr
@@ -8,7 +8,7 @@ module Chalk
     property register : Int32
     property value : Int32
 
-    def initialize(@register : Int32, @value : Int32)
+    def initialize(@register, @value)
     end
 
     def to_s(io)
@@ -22,7 +22,7 @@ module Chalk
     property into : Int32
     property from : Int32
 
-    def initialize(@into : Int32, @from : Int32)
+    def initialize(@into, @from)
     end
 
     def to_s(io)
@@ -38,8 +38,7 @@ module Chalk
     property into : Int32
     property value : Int32
 
-    def initialize(@op : TokenType, @into : Int32,
-                   @value : Int32)
+    def initialize(@op, @into, @value)
     end
 
     def to_s(io)
@@ -54,7 +53,7 @@ module Chalk
     property into : Int32
     property from : Int32
 
-    def initialize(@op : TokenType, @into : Int32, @from : Int32)
+    def initialize(@op, @into, @from)
     end
 
     def to_s(io)
@@ -68,7 +67,7 @@ module Chalk
   class StoreInstruction < Instruction
     property up_to : Int32
 
-    def initialize(@up_to : Int32)
+    def initialize(@up_to)
     end
 
     def to_s(io)
@@ -80,7 +79,7 @@ module Chalk
   class RestoreInstruction < Instruction
     property up_to : Int32
 
-    def initialize(@up_to : Int32)
+    def initialize(@up_to)
     end
 
     def to_s(io)
@@ -92,7 +91,7 @@ module Chalk
   class ReturnInstruction < Instruction
     property to_return : Int32
 
-    def initialize(@to_return : Int32)
+    def initialize(@to_return)
     end
 
     def to_s(io)
@@ -100,4 +99,36 @@ module Chalk
       @to_return.to_s(16, io)
     end
   end
+
+  class JumpEqInstruction < Instruction
+    property offset : Int32
+    property left : Int32
+    property right : Int32
+
+    def initialize(@offset, @left, @right)
+    end
+
+    def to_s(io)
+      io << "jeq " << offset << " R"
+      @left.to_s(16, io)
+      io << " " << right
+    end
+  end
+
+  class JumpEqRegInstruction < Instruction
+    property offset : Int32
+    property left : Int32
+    property right : Int32
+
+    def initialize(@offset, @left, @right)
+    end
+
+    def to_s(io)
+      io << "jeq " << offset << " R"
+      @left.to_s(16, io)
+      io << " R"
+      @right.to_s(16, io)
+    end
+  end
+  
 end
diff --git a/src/chalk/parsers.cr b/src/chalk/parsers.cr
index 8d530a7..5ea58de 100644
--- a/src/chalk/parsers.cr
+++ b/src/chalk/parsers.cr
@@ -5,8 +5,7 @@ module Chalk
     abstract def parse?(tokens : Array(Token),
                         index : Int64) : Tuple(T, Int64)?
 
-    def parse(tokens : Array(Token),
-              index : Int64) : Tuple(T, Int64)
+    def parse(tokens, index)
       return parse?(tokens, index).not_nil!
     end
 
diff --git a/src/chalk/table.cr b/src/chalk/table.cr
index 387b80a..db3611d 100644
--- a/src/chalk/table.cr
+++ b/src/chalk/table.cr
@@ -6,7 +6,7 @@ module Chalk
     property function : TreeFunction
     property addr : Int32
 
-    def initialize(@function : TreeFunction, @addr : Int32 = -1)
+    def initialize(@function, @addr = -1)
     end
 
     def to_s(io)
@@ -17,7 +17,7 @@ module Chalk
   class VarEntry < Entry
     property register : Int32
 
-    def initialize(@register : Int32)
+    def initialize(@register)
     end
 
     def to_s(io)
@@ -28,11 +28,11 @@ module Chalk
   class Table
     property parent : Table?
 
-    def initialize(@parent : Table? = nil)
+    def initialize(@parent = nil)
       @data = {} of String => Entry
     end
 
-    def []?(key) : Entry?
+    def []?(key)
       if entry = @data[key]?
         return entry
       end
diff --git a/src/chalk/tree.cr b/src/chalk/tree.cr
index 624c48e..8fa223e 100644
--- a/src/chalk/tree.cr
+++ b/src/chalk/tree.cr
@@ -1,25 +1,25 @@
 module Chalk
   class Visitor
-    def visit(tree : Tree)
+    def visit(tree)
     end
 
-    def finish(tree : Tree)
+    def finish(tree)
     end
   end
 
   class Transformer
-    def transform(tree : Tree) : Tree
+    def transform(tree)
       return tree
     end
   end
 
   class Tree
-    def accept(v : Visitor)
+    def accept(v)
       v.visit(self)
       v.finish(self)
     end
 
-    def apply(t : Transformer)
+    def apply(t)
       return t.transform(self)
     end
   end
@@ -27,14 +27,14 @@ module Chalk
   class TreeId < Tree
     property id : String
 
-    def initialize(@id : String)
+    def initialize(@id)
     end
   end
 
   class TreeLit < Tree
     property lit : Int64
 
-    def initialize(@lit : Int64)
+    def initialize(@lit)
     end
   end
 
@@ -42,16 +42,16 @@ module Chalk
     property name : String
     property params : Array(Tree)
 
-    def initialize(@name : String, @params : Array(Tree))
+    def initialize(@name, @params)
     end
 
-    def accept(v : Visitor)
+    def accept(v)
       v.visit(self)
       @params.each &.accept(v)
       v.finish(self)
     end
 
-    def apply(t : Transformer)
+    def apply(t)
       @params.map! do |param|
         param.apply(t)
       end
@@ -64,17 +64,17 @@ module Chalk
     property left : Tree
     property right : Tree
 
-    def initialize(@op : TokenType, @left : Tree, @right : Tree)
+    def initialize(@op, @left, @right)
     end
 
-    def accept(v : Visitor)
+    def accept(v)
       v.visit(self)
       @left.accept(v)
       @right.accept(v)
       v.finish(self)
     end
 
-    def apply(t : Transformer)
+    def apply(t)
       @left = @left.apply(t)
       @right = @right.apply(t)
       return t.transform(self)
@@ -84,16 +84,16 @@ module Chalk
   class TreeBlock < Tree
     property children : Array(Tree)
 
-    def initialize(@children : Array(Tree))
+    def initialize(@children)
     end
 
-    def accept(v : Visitor)
+    def accept(v)
       v.visit(self)
       @children.each &.accept(v)
       v.finish(self)
     end
 
-    def apply(t : Transformer)
+    def apply(t)
       @children.map! do |child|
         child.apply(t)
       end
@@ -106,16 +106,16 @@ module Chalk
     property params : Array(String)
     property block : Tree
 
-    def initialize(@name : String, @params : Array(String), @block : Tree)
+    def initialize(@name, @params, @block)
     end
 
-    def accept(v : Visitor)
+    def accept(v)
       v.visit(self)
       @block.accept(v)
       v.finish(self)
     end
 
-    def apply(t : Transformer)
+    def apply(t)
       @block = @block.apply(t)
       return t.transform(self)
     end
@@ -125,16 +125,16 @@ module Chalk
     property name : String
     property expr : Tree
 
-    def initialize(@name : String, @expr : Tree)
+    def initialize(@name, @expr)
     end
 
-    def accept(v : Visitor)
+    def accept(v)
       v.visit(self)
       @expr.accept(v)
       v.finish(self)
     end
 
-    def apply(t : Transformer)
+    def apply(t)
       @expr = @expr.apply(t)
       return t.transform(self)
     end
@@ -144,16 +144,16 @@ module Chalk
     property name : String
     property expr : Tree
 
-    def initialize(@name : String, @expr : Tree)
+    def initialize(@name, @expr)
     end
 
-    def accept(v : Visitor)
+    def accept(v)
       v.visit(self)
       @expr.accept(v)
       v.finish(self)
     end
 
-    def apply(t : Transformer)
+    def apply(t)
       @expr = @expr.apply(t)
       return t.transform(self)
     end
@@ -164,10 +164,10 @@ module Chalk
     property block : Tree
     property otherwise : Tree?
 
-    def initialize(@condition : Tree, @block : Tree, @otherwise : Tree? = nil)
+    def initialize(@condition, @block, @otherwise = nil)
     end
 
-    def accept(v : Visitor)
+    def accept(v)
       v.visit(self)
       @condition.accept(v)
       @block.accept(v)
@@ -175,7 +175,7 @@ module Chalk
       v.finish(self)
     end
 
-    def apply(t : Transformer)
+    def apply(t)
       @condition = @condition.apply(t)
       @block = @block.apply(t)
       @otherwise = @otherwise.try &.apply(t)
@@ -187,17 +187,17 @@ module Chalk
     property condition : Tree
     property block : Tree
 
-    def initialize(@condition : Tree, @block : Tree)
+    def initialize(@condition, @block)
     end
 
-    def accept(v : Visitor)
+    def accept(v)
       v.visit(self)
       @condition.accept(v)
       @block.accept(v)
       v.finish(self)
     end
 
-    def apply(t : Transformer)
+    def apply(t)
       @condition = @condition.apply(t)
       @block = @block.apply(t)
       return t.transform(self)
@@ -207,16 +207,16 @@ module Chalk
   class TreeReturn < Tree
     property rvalue : Tree
 
-    def initialize(@rvalue : Tree)
+    def initialize(@rvalue)
     end
 
-    def accept(v : Visitor)
+    def accept(v)
       v.visit(self)
       @rvalue.accept(v)
       v.finish(self)
     end
 
-    def apply(t : Transformer)
+    def apply(t)
       @rvalue = @rvalue.apply(t)
       return t.transform(self)
     end
diff --git a/src/chalk/ui.cr b/src/chalk/ui.cr
index 2bce834..15f812f 100644
--- a/src/chalk/ui.cr
+++ b/src/chalk/ui.cr
@@ -9,7 +9,7 @@ module Chalk
     property file : String
     property mode : OutputMode
 
-    def initialize(@file : String = "",
+    def initialize(@file = "",
                    @mode = OutputMode::Tree)
     end