Reapply revisions 1432, 1433, 1469 and 1472 while fixing issue 279.

src/ast.h

Index: src/ast.h
===================================================================
--- src/ast.h	(revision 1544)
+++ src/ast.h	(working copy)
@@ -95,6 +95,7 @@
 
 // Forward declarations
 class TargetCollector;
+class MaterializedLiteral;
 
 #define DEF_FORWARD_DECLARATION(type) class type;
 NODE_LIST(DEF_FORWARD_DECLARATION)
@@ -129,6 +130,9 @@
   virtual BinaryOperation* AsBinaryOperation() { return NULL; }
   virtual Assignment* AsAssignment() { return NULL; }
   virtual FunctionLiteral* AsFunctionLiteral() { return NULL; }
+  virtual MaterializedLiteral* AsMaterializedLiteral() { return NULL; }
+  virtual ObjectLiteral* AsObjectLiteral() { return NULL; }
+  virtual ArrayLiteral* AsArrayLiteral() { return NULL; }
 
   void set_statement_pos(int statement_pos) { statement_pos_ = statement_pos; }
   int statement_pos() const { return statement_pos_; }
@@ -636,11 +640,23 @@
 // Base class for literals that needs space in the corresponding JSFunction.
 class MaterializedLiteral: public Expression {
  public:
-  explicit MaterializedLiteral(int literal_index)
-      : literal_index_(literal_index) {}
+  explicit MaterializedLiteral(int literal_index, bool is_simple, int depth)
+      : literal_index_(literal_index), is_simple_(is_simple), depth_(depth) {}
+
+  virtual MaterializedLiteral* AsMaterializedLiteral() { return this; }
+
   int literal_index() { return literal_index_; }
+
+  // A materialized literal is simple if the values consist of only
+  // constants and simple object and array literals.
+  bool is_simple() const { return is_simple_; }
+
+  int depth() const { return depth_; }
+
  private:
   int literal_index_;
+  bool is_simple_;
+  int depth_;
 };
 
 
@@ -655,10 +671,11 @@
    public:
 
     enum Kind {
-      CONSTANT,       // Property with constant value (at compile time).
-      COMPUTED,       // Property with computed value (at execution time).
-      GETTER, SETTER,  // Property is an accessor function.
-      PROTOTYPE       // Property is __proto__.
+      CONSTANT,              // Property with constant value (compile time).
+      COMPUTED,              // Property with computed value (execution time).
+      MATERIALIZED_LITERAL,  // Property value is a materialized literal.
+      GETTER, SETTER,        // Property is an accessor function.
+      PROTOTYPE              // Property is __proto__.
     };
 
     Property(Literal* key, Expression* value);
@@ -676,12 +693,14 @@
 
   ObjectLiteral(Handle<FixedArray> constant_properties,
                 ZoneList<Property*>* properties,
-                int literal_index)
-      : MaterializedLiteral(literal_index),
+                int literal_index,
+                bool is_simple,
+                int depth)
+      : MaterializedLiteral(literal_index, is_simple, depth),
         constant_properties_(constant_properties),
-        properties_(properties) {
-  }
+        properties_(properties) {}
 
+  virtual ObjectLiteral* AsObjectLiteral() { return this; }
   virtual void Accept(AstVisitor* v);
 
   Handle<FixedArray> constant_properties() const {
@@ -701,7 +720,7 @@
   RegExpLiteral(Handle<String> pattern,
                 Handle<String> flags,
                 int literal_index)
-      : MaterializedLiteral(literal_index),
+      : MaterializedLiteral(literal_index, false, 1),
         pattern_(pattern),
         flags_(flags) {}
 
@@ -717,14 +736,19 @@
 
 // An array literal has a literals object that is used
 // for minimizing the work when constructing it at runtime.
-class ArrayLiteral: public Expression {
+class ArrayLiteral: public MaterializedLiteral {
  public:
   ArrayLiteral(Handle<FixedArray> literals,
-               ZoneList<Expression*>* values)
-      : literals_(literals), values_(values) {
-  }
+               ZoneList<Expression*>* values,
+               int literal_index,
+               bool is_simple,
+               int depth)
+      : MaterializedLiteral(literal_index, is_simple, depth),
+        literals_(literals),
+        values_(values) {}
 
   virtual void Accept(AstVisitor* v);
+  virtual ArrayLiteral* AsArrayLiteral() { return this; }
 
   Handle<FixedArray> literals() const { return literals_; }
   ZoneList<Expression*>* values() const { return values_; }