Improve the code generated by the full codegen by keeping...

src/full-codegen.h

 // Copyright 2010 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 55 matching lines @@
 
 class FullCodeGenerator: public AstVisitor {
  public:
   explicit FullCodeGenerator(MacroAssembler* masm)
       : masm_(masm),
         info_(NULL),
         nesting_stack_(NULL),
         loop_depth_(0),
         location_(kStack),
         true_label_(NULL),
-        false_label_(NULL) {
+        false_label_(NULL),
+        fall_through_(NULL) {
   }
 
   static Handle<Code> MakeCode(CompilationInfo* info);
 
   void Generate(CompilationInfo* info);
 
  private:
   class Breakable;
   class Iteration;
   class TryCatch;
@@ skipping 164 matching lines @@
 
   // Emit code to discard count elements from the top of stack, then convert
   // a pure value into the result expected according to an expression
   // context.
   void DropAndApply(int count, Expression::Context context, Register reg);
 
   // Set up branch labels for a test expression.
   void PrepareTest(Label* materialize_true,
                    Label* materialize_false,
                    Label** if_true,
-                   Label** if_false);
+                   Label** if_false,
+                   Label** fall_through);
 
   // Emit code to convert pure control flow to a pair of labels into the
   // result expected according to an expression context.
   void Apply(Expression::Context context,
              Label* materialize_true,
              Label* materialize_false);
 
   // Emit code to convert constant control flow (true or false) into
   // the result expected according to an expression context.
   void Apply(Expression::Context context, bool flag);
@@ skipping 28 matching lines @@
   void VisitForValue(Expression* expr, Location where) {
     Expression::Context saved_context = context_;
     Location saved_location = location_;
     context_ = Expression::kValue;
     location_ = where;
     Visit(expr);
     context_ = saved_context;
     location_ = saved_location;
   }
 
-  void VisitForControl(Expression* expr, Label* if_true, Label* if_false) {
+  void VisitForControl(Expression* expr,
+                       Label* if_true,
+                       Label* if_false,
+                       Label* fall_through) {
     Expression::Context saved_context = context_;
     Label* saved_true = true_label_;
     Label* saved_false = false_label_;
+    Label* saved_fall_through = fall_through_;
     context_ = Expression::kTest;
     true_label_ = if_true;
     false_label_ = if_false;
+    fall_through_ = fall_through;
     Visit(expr);
     context_ = saved_context;
     true_label_ = saved_true;
     false_label_ = saved_false;
+    fall_through_ = saved_fall_through;
   }
 
   void VisitDeclarations(ZoneList<Declaration*>* declarations);
   void DeclareGlobals(Handle<FixedArray> pairs);
 
   // Try to perform a comparison as a fast inlined literal compare if
   // the operands allow it.  Returns true if the compare operations
   // has been matched and all code generated; false otherwise.
   bool TryLiteralCompare(Token::Value op,
                          Expression* left,
@@ skipping 121 matching lines @@
   CompilationInfo* info_;
 
   Label return_label_;
   NestedStatement* nesting_stack_;
   int loop_depth_;
 
   Expression::Context context_;
   Location location_;
   Label* true_label_;
   Label* false_label_;
+  Label* fall_through_;
 
   friend class NestedStatement;
 
   DISALLOW_COPY_AND_ASSIGN(FullCodeGenerator);
 };
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_FULL_CODEGEN_H_