Scope tree serialization and ScopeIterator cleanup.

src/scopes.h

 // Copyright 2011 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 71 matching lines @@
 // corresponding variable (though some are bound during parse time). Variable
 // allocation binds each unresolved VariableProxy to one Variable and assigns
 // a location. Note that many VariableProxy nodes may refer to the same Java-
 // Script variable.
 
 class Scope: public ZoneObject {
  public:
   // ---------------------------------------------------------------------------
   // Construction
 
-  enum Type {
-    EVAL_SCOPE,      // The top-level scope for an eval source.
-    FUNCTION_SCOPE,  // The top-level scope for a function.
-    GLOBAL_SCOPE,    // The top-level scope for a program or a top-level eval.
-    CATCH_SCOPE,     // The scope introduced by catch.
-    BLOCK_SCOPE,     // The scope introduced by a new block.
-    WITH_SCOPE       // The scope introduced by with.
-  };
-
-  Scope(Scope* outer_scope, Type type);
+  Scope(Scope* outer_scope, ScopeType type);
 
   // Compute top scope and allocate variables. For lazy compilation the top
   // scope only contains the single lazily compiled function, so this
   // doesn't re-allocate variables repeatedly.
   static bool Analyze(CompilationInfo* info);
 
   static Scope* DeserializeScopeChain(CompilationInfo* info,
                                       Scope* innermost_scope);
 
   // The scope name is only used for printing/debugging.
@@ skipping 87 matching lines @@
   void RecordWithStatement() { scope_contains_with_ = true; }
 
   // Inform the scope that the corresponding code contains an eval call.
   void RecordEvalCall() { if (!is_global_scope()) scope_calls_eval_ = true; }
 
   // Enable strict mode for the scope (unless disabled by a global flag).
   void EnableStrictMode() {
     strict_mode_ = FLAG_strict_mode;
   }
 
+  // Position in the source where this scope begins and ends.
+  //
+  // * For the scope of a with statement
+  //     with (obj) stmt
+  //   start position: start position of first token of 'stmt'
+  //   end position: end position of last token of 'stmt'
+  // * For the scope of a block
+  //     { stmts }
+  //   start position: start position of '{'
+  //   end position: end position of '}'
+  // * For the scope of a function literal or decalaration
+  //     function fun(a,b) { stmts }
+  //   start position: start position of '('
+  //   end position: end position of '}'
+  // * For the scope of a catch block
+  //     try { stms } catch(e) { stmts }
+  //   start position: start position of '('
+  //   end position: end position of ')'
+  // * For the scope of a for-statement
+  //     for (let x ...) stmt
+  //   start position: start position of '('
+  //   end position: end position of last token of 'stmt'
+  int start_position() const { return start_position_; }
+  void set_start_position(int statement_pos) {
+    start_position_ = statement_pos;
+  }
+  int end_position() const { return end_position_; }
+  void set_end_position(int statement_pos) {
+    end_position_ = statement_pos;
+  }
+
   // ---------------------------------------------------------------------------
   // Predicates.
 
   // Specific scope types.
   bool is_eval_scope() const { return type_ == EVAL_SCOPE; }
   bool is_function_scope() const { return type_ == FUNCTION_SCOPE; }
   bool is_global_scope() const { return type_ == GLOBAL_SCOPE; }
   bool is_catch_scope() const { return type_ == CATCH_SCOPE; }
   bool is_block_scope() const { return type_ == BLOCK_SCOPE; }
   bool is_with_scope() const { return type_ == WITH_SCOPE; }
@@ skipping 18 matching lines @@
   bool inside_with() const { return scope_inside_with_; }
   // Does this scope contain a with statement.
   bool contains_with() const { return scope_contains_with_; }
 
   // The scope immediately surrounding this scope, or NULL.
   Scope* outer_scope() const { return outer_scope_; }
 
   // ---------------------------------------------------------------------------
   // Accessors.
 
+  // The type of this scope.
+  ScopeType type() const { return type_; }
+
   // The variable corresponding the 'this' value.
   Variable* receiver() { return receiver_; }
 
   // The variable holding the function literal for named function
   // literals, or NULL.
   // Only valid for function scopes.
   VariableProxy* function() const {
     ASSERT(is_function_scope());
     return function_;
   }
 
   // Parameters. The left-most parameter has index 0.
   // Only valid for function scopes.
   Variable* parameter(int index) const {
     ASSERT(is_function_scope());
     return params_[index];
   }
 
   int num_parameters() const { return params_.length(); }
 
   // The local variable 'arguments' if we need to allocate it; NULL otherwise.
   Variable* arguments() const { return arguments_; }
 
   // Declarations list.
   ZoneList<Declaration*>* declarations() { return &decls_; }
 
+  // Inner scope list.
+  ZoneList<Scope*>* inner_scopes() { return &inner_scopes_; }
 
   // ---------------------------------------------------------------------------
   // Variable allocation.
 
   // Collect all used locals in this scope.
   template<class Allocator>
   void CollectUsedVariables(List<Variable*, Allocator>* locals);
 
   // Resolve and fill in the allocation information for all variables
   // in this scopes. Must be called *after* all scopes have been
@@ skipping 23 matching lines @@
 
   // The number of contexts between this and scope; zero if this == scope.
   int ContextChainLength(Scope* scope);
 
   // Find the first function, global, or eval scope.  This is the scope
   // where var declarations will be hoisted to in the implementation.
   Scope* DeclarationScope();
 
   Handle<SerializedScopeInfo> GetSerializedScopeInfo();
 
+  // Get the chain of nested scopes within this scope for the source statement
+  // position. The scopes will be added to the list from the outermost scope to
+  // the innermost scope. Only nested block, catch or with scopes are tracked
+  // and will be returned, but no inner function scopes.
+  void GetNestedScopeChain(List<Handle<SerializedScopeInfo> >* chain,
+                           int statement_position);
+
   // ---------------------------------------------------------------------------
   // Strict mode support.
   bool IsDeclared(Handle<String> name) {
     // During formal parameter list parsing the scope only contains
     // two variables inserted at initialization: "this" and "arguments".
     // "this" is an invalid parameter name and "arguments" is invalid parameter
     // name in strict mode. Therefore looking up with the map which includes
     // "this" and "arguments" in addition to all formal parameters is safe.
     return variables_.Lookup(name) != NULL;
   }
 
   // ---------------------------------------------------------------------------
   // Debugging.
 
 #ifdef DEBUG
   void Print(int n = 0);  // n = indentation; n < 0 => don't print recursively
 #endif
 
   // ---------------------------------------------------------------------------
   // Implementation.
  protected:
   friend class ParserFactory;
 
-  explicit Scope(Type type);
+  explicit Scope(ScopeType type);
 
   Isolate* const isolate_;
 
   // Scope tree.
   Scope* outer_scope_;  // the immediately enclosing outer scope, or NULL
   ZoneList<Scope*> inner_scopes_;  // the immediately enclosed inner scopes
 
   // The scope type.
-  Type type_;
+  ScopeType type_;
 
   // Debugging support.
   Handle<String> scope_name_;
 
   // The variables declared in this scope:
   //
   // All user-declared variables (incl. parameters).  For global scopes
   // variables may be implicitly 'declared' by being used (possibly in
   // an inner scope) with no intervening with statements or eval calls.
   VariableMap variables_;
@@ skipping 21 matching lines @@
   //
   // This scope is inside a 'with' of some outer scope.
   bool scope_inside_with_;
   // This scope contains a 'with' statement.
   bool scope_contains_with_;
   // This scope or a nested catch scope or with scope contain an 'eval' call. At
   // the 'eval' call site this scope is the declaration scope.
   bool scope_calls_eval_;
   // This scope is a strict mode scope.
   bool strict_mode_;
+  // Source positions.
+  int start_position_;
+  int end_position_;
 
   // Computed via PropagateScopeInfo.
   bool outer_scope_calls_non_strict_eval_;
   bool inner_scope_calls_eval_;
   bool force_eager_compilation_;
 
   // True if it doesn't need scope resolution (e.g., if the scope was
   // constructed based on a serialized scope info or a catch context).
   bool already_resolved_;
 
@@ skipping 82 matching lines @@
   // Variable allocation.
   void AllocateStackSlot(Variable* var);
   void AllocateHeapSlot(Variable* var);
   void AllocateParameterLocals();
   void AllocateNonParameterLocal(Variable* var);
   void AllocateNonParameterLocals();
   void AllocateVariablesRecursively();
 
  private:
   // Construct a scope based on the scope info.
-  Scope(Scope* inner_scope, Type type, Handle<SerializedScopeInfo> scope_info);
+  Scope(Scope* inner_scope,
+        ScopeType type,
+        Handle<SerializedScopeInfo> scope_info);
 
   // Construct a catch scope with a binding for the name.
   Scope(Scope* inner_scope, Handle<String> catch_variable_name);
 
   void AddInnerScope(Scope* inner_scope) {
     if (inner_scope != NULL) {
       inner_scopes_.Add(inner_scope);
       inner_scope->outer_scope_ = this;
     }
   }
 
-  void SetDefaults(Type type,
+  void SetDefaults(ScopeType type,
                    Scope* outer_scope,
                    Handle<SerializedScopeInfo> scope_info);
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_SCOPES_H_