Move more nodes to the optimizing code generator.

runtime/vm/code_generator_ia32.h

Index: runtime/vm/code_generator_ia32.h
===================================================================
--- runtime/vm/code_generator_ia32.h	(revision 1822)
+++ runtime/vm/code_generator_ia32.h	(working copy)
@@ -19,9 +19,68 @@
 // Forward Declarations.
 class Assembler;
 class AstNode;
-class CodeGeneratorState;
+class CodeGenerator;
 class SourceLabel;
 
+
+class CodeGeneratorState : public StackResource {
+ public:
+  explicit CodeGeneratorState(CodeGenerator* codegen);
+  virtual ~CodeGeneratorState();
+
+  CodeGeneratorState* parent() const { return parent_; }
+
+  AstNode* root_node() const { return root_node_; }
+  void set_root_node(AstNode* value) { root_node_ = value; }
+  bool IsRootNode(AstNode* node) const {
+    return root_node_ == node;
+  }
+
+  int loop_level() const { return loop_level_; }
+  void set_loop_level(int loop_level) {
+    loop_level_ = loop_level;
+  }
+
+  int context_level() const { return context_level_; }
+  void set_context_level(int context_level) {
+    context_level_ = context_level;
+  }
+
+  int try_index() const { return current_try_index_; }
+  void set_try_index(int value) {
+    current_try_index_ = value;
+  }
+
+ private:
+  CodeGenerator* codegen_;
+  CodeGeneratorState* parent_;
+  AstNode* root_node_;
+
+  // The loop level reflects the lexical nesting of loop statements, regardless
+  // of the presence of captured variables.
+  int loop_level_;
+
+  // The runtime context level is only incremented when a new context is
+  // allocated and chained to the list of contexts. This occurs when the scopes
+  // at the current loop level contain captured variables.
+  int context_level_;
+
+  // We identify each try block in this function with an unique 'try index'
+  // value.
+  // The 'try index' is used to match the try blocks with the corresponding
+  // catch block (if one exists). The PC descriptors generated for
+  // statements in the try block use this index so that it can be matched
+  // to the appropriate catch block.
+  // The 'try index' value is generated by incrementing the try_index_
+  // variable in the CodeGenerator object.
+  // We store the 'try index' of the block of code that we are
+  // currently generating code for in the current_try_index_ variable.
+  int current_try_index_;
+
+  DISALLOW_IMPLICIT_CONSTRUCTORS(CodeGeneratorState);
+};
+
+
 class CodeGenerator : public AstNodeVisitor {
  public:
   CodeGenerator(Assembler* assembler, const ParsedFunction& parsed_function);
@@ -63,6 +122,8 @@
 
   virtual void CountBackwardLoop();
 
+  void GenerateReturnEpilog();
+
  private:
   // TODO(srdjan): Remove the friendship once the two compilers are properly
   // structured.