Reapply r9673 "Scope tree serialization and ScopeIterator cleanup."

src/scopes.h

Index: src/scopes.h
diff --git a/src/scopes.h b/src/scopes.h
index 72f1e31878efb744ac8d1210f531d1d16b7a0026..58b683b8d3e506f9ac5a54feabefbed35987a212 100644
--- a/src/scopes.h
+++ b/src/scopes.h
@@ -89,16 +89,7 @@ class Scope: public ZoneObject {
   // ---------------------------------------------------------------------------
   // 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
@@ -206,6 +197,37 @@ class Scope: public ZoneObject {
     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.
 
@@ -244,6 +266,9 @@ class Scope: public ZoneObject {
   // ---------------------------------------------------------------------------
   // Accessors.
 
+  // The type of this scope.
+  ScopeType type() const { return type_; }
+
   // The variable corresponding the 'this' value.
   Variable* receiver() { return receiver_; }
 
@@ -270,6 +295,8 @@ class Scope: public ZoneObject {
   // Declarations list.
   ZoneList<Declaration*>* declarations() { return &decls_; }
 
+  // Inner scope list.
+  ZoneList<Scope*>* inner_scopes() { return &inner_scopes_; }
 
   // ---------------------------------------------------------------------------
   // Variable allocation.
@@ -313,6 +340,13 @@ class Scope: public ZoneObject {
 
   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) {
@@ -336,7 +370,7 @@ class Scope: public ZoneObject {
  protected:
   friend class ParserFactory;
 
-  explicit Scope(Type type);
+  explicit Scope(ScopeType type);
 
   Isolate* const isolate_;
 
@@ -345,7 +379,7 @@ class Scope: public ZoneObject {
   ZoneList<Scope*> inner_scopes_;  // the immediately enclosed inner scopes
 
   // The scope type.
-  Type type_;
+  ScopeType type_;
 
   // Debugging support.
   Handle<String> scope_name_;
@@ -387,6 +421,9 @@ class Scope: public ZoneObject {
   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_;
@@ -489,7 +526,9 @@ class Scope: public ZoneObject {
 
  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);
@@ -501,7 +540,7 @@ class Scope: public ZoneObject {
     }
   }
 
-  void SetDefaults(Type type,
+  void SetDefaults(ScopeType type,
                    Scope* outer_scope,
                    Handle<SerializedScopeInfo> scope_info);
 };