Remove some of the state-dependent behavior from the code generator....

src/ast.h

Index: src/ast.h
===================================================================
--- src/ast.h	(revision 246)
+++ src/ast.h	(working copy)
@@ -140,6 +140,8 @@
 };
 
 
+class Reference;
+
 class Expression: public Node {
  public:
   virtual Expression* AsExpression()  { return this; }
@@ -150,6 +152,18 @@
   // statement. This is used to transform postfix increments to
   // (faster) prefix increments.
   virtual void MarkAsStatement() { /* do nothing */ }
+
+  // Generate code to store into an expression evaluated as the left-hand
+  // side of an assignment.  The code will expect the stored value on top of
+  // the expression stack, and a reference containing the expression
+  // immediately below that.  This function is overridden for expression
+  // types that can be stored into.
+  virtual void GenerateStoreCode(MacroAssembler* masm,
+                                 Scope* scope,
+                                 Reference* ref,
+                                 bool is_const_init) {

[iposva, 2008/09/10 18:01:44]

Can you please use an enum for the is_const_init to improve the readability at
the caller sites?

[Kevin Millikin (Chromium), 2008/09/11 07:15:55]

Done.  InitState with values CONST_INIT and NOT_CONST_INIT defined in ast.h for
now, but will move to a more logical place as the codegen state evolves.

+    UNREACHABLE();
+  }
 };
 
 
@@ -753,6 +767,14 @@
   // Bind this proxy to the variable var.
   void BindTo(Variable* var);
 
+  // Generate code to store into an expression evaluated as the left-hand
+  // side of an assignment.  The code will expect the stored value on top of
+  // the expression stack, and a reference containing the expression
+  // immediately below that.
+  virtual void GenerateStoreCode(MacroAssembler* masm,
+                                 Scope* scope,
+                                 Reference* ref,
+                                 bool is_const_init);
  protected:
   Handle<String> name_;
   Variable* var_;  // resolved variable, or NULL
@@ -828,6 +850,14 @@
   Type type() const  { return type_; }
   int index() const  { return index_; }
 
+  // Generate code to store into an expression evaluated as the left-hand
+  // side of an assignment.  The code will expect the stored value on top of
+  // the expression stack, and a reference containing the expression
+  // immediately below that.
+  virtual void GenerateStoreCode(MacroAssembler* masm,
+                                 Scope* scope,
+                                 Reference* ref,
+                                 bool is_const_init);
  private:
   Variable* var_;
   Type type_;
@@ -855,6 +885,14 @@
   // during preparsing.
   static Property* this_property() { return &this_property_; }
 
+  // Generate code to store into an expression evaluated as the left-hand
+  // side of an assignment.  The code will expect the stored value on top of
+  // the expression stack, and a reference containing the expression
+  // immediately below that.
+  virtual void GenerateStoreCode(MacroAssembler* masm,
+                                 Scope* scope,
+                                 Reference* ref,
+                                 bool is_const_init);
  private:
   Expression* obj_;
   Expression* key_;